72 results on '"Björkman-Burtscher IM"'
Search Results
2. Description and validation of a scoring system for tomosynthesis in pulmonary cystic fibrosis.
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Vult von Steyern K, Björkman-Burtscher IM, Höglund P, Bozovic G, Wiklund M, Geijer M, Vult von Steyern, Kristina, Björkman-Burtscher, Isabella M, Höglund, Peter, Bozovic, Gracijela, Wiklund, Marie, and Geijer, Mats
- Abstract
Objectives: To design and validate a scoring system for tomosynthesis (digital tomography) in pulmonary cystic fibrosis.Methods: A scoring system dedicated to tomosynthesis in pulmonary cystic fibrosis was designed. Three radiologists independently scored 88 pairs of radiographs and tomosynthesis examinations of the chest in 60 patients with cystic fibrosis and 7 oncology patients. Radiographs were scored according to the Brasfield scoring system and tomosynthesis examinations were scored using the new scoring system.Results: Observer agreements for the tomosynthesis score were almost perfect for the total score with square-weighted kappa >0.90, and generally substantial to almost perfect for subscores. Correlation between the tomosynthesis score and the Brasfield score was good for the three observers (Kendall's rank correlation tau 0.68, 0.77 and 0.78). Tomosynthesis was generally scored higher as a percentage of the maximum score. Observer agreements for the total score for Brasfield score were almost perfect (square-weighted kappa 0.80, 0.81 and 0.85).Conclusions: The tomosynthesis scoring system seems robust and correlates well with the Brasfield score. Compared with radiography, tomosynthesis is more sensitive to cystic fibrosis changes, especially bronchiectasis and mucus plugging, and the new tomosynthesis scoring system offers the possibility of more detailed and accurate scoring of disease severity.Key Points: Tomosynthesis is more sensitive than conventional radiography for pulmonary cystic fibrosis changes. The radiation dose from chest tomosynthesis is low compared with computed tomography. Tomosynthesis may become useful in the regular follow-up of patients with cystic fibrosis. [ABSTRACT FROM AUTHOR]- Published
- 2012
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3. CT angiography of intracranial arterial vessels: impact of tube voltage and contrast media concentration on image quality.
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Ramgren B, Björkman-Burtscher IM, Holtås S, Siemund R, Ramgren, Birgitta, Björkman-Burtscher, Isabella M, Holtås, Stig, and Siemund, Roger
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BLOOD vessels , *TOMOGRAPHY , *ANGIOGRAPHY , *RADIOSCOPIC diagnosis , *MEDICAL radiography , *ARTERIES - Abstract
Background: Computed tomography angiography (CTA) of intracranial arteries has high demands on image quality. Important parameters influencing vessel enhancement are injection rate, concentration of contrast media and tube voltage.Purpose: To evaluate the impact of an increase of contrast media concentration from 300 to 400 mg iodine/mL (mgI/mL) and the effect of a decrease of tube voltage from 120 to 90 kVp on vessel attenuation and image quality in CT angiography of intracranial arteries.Material and Methods: Sixty-three patients were included into three protocol groups: Group I, 300 mgI/mL 120 kVp; Group II, 400 mgI/mL 120 kVp; Group III, 400 mgI/mL 90 kVp. Hounsfield units (HU) were measured in the internal carotid artery (ICA) and the M1 and M2 segments of the middle cerebral artery. Image quality grading was performed regarding M1 and M2 segments, volume rendering and general image impression.Results: The difference in mean HU in ICA concerning the effect of contrast media concentration was statistically significant (P = 0.03) in favor of higher concentration. The difference in ICA enhancement due to the effect of tube voltage was statistically significant (P < 0.01) in favor of lower tube voltage. The increase of contrast medium concentration raised the mean enhancement in ICA with 18% and the decrease of tube voltage raised the mean enhancement with 37%. Image quality grading showed a trend towards improved grading for higher contrast concentration and lower tube voltage. Statistically significant better grading was found for the combined effect of both measures except for general impression (P 0.01-0.05).Conclusion: The uses of highly concentrated contrast media and low tube voltage are easily performed measures to improve image quality in CTA of intracranial vessel. [ABSTRACT FROM AUTHOR]- Published
- 2012
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4. Radiation dose reduction in CT of the brain: can advanced noise filtering compensate for loss of image quality?
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Siemund, Roger, Löve, A, van Westen, D, Stenberg, L, Petersen, C, and Björkman-Burtscher, IM
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BACKGROUND: Computed tomography (CT) of the brain is performed with high local doses due to high demands on low contrast resolution. Advanced algorithms for noise reduction might be able to preserve critical image information when reducing radiation dose. PURPOSE: To evaluate the effect of advanced noise filtering on image quality in brain CT acquired with reduced radiation dose. MATERIAL AND METHODS: Thirty patients referred for non-enhanced CT of the brain were examined with two helical protocols: normal dose (ND, CTDIvol57 mGy) and low dose (LD, CTDIvol40 mGy) implying a 30% radiation dose reduction. Images from the LD examinations were also postprocessed with a noise reduction software with non-linear filters (SharpView CT), creating filtered low dose images (FLD) for each patient. The three image stacks for each patient were presented side by side in randomized order. Five radiologists, blinded for dose level and filtering, ranked these three axial image stacks (ND, LD, FLD) as best to poorest (1 to 3) regarding three image quality criteria. Measurements of mean Hounsfield units (HU) and standard deviation (SD) of the HU were calculated for large region of interest in the centrum semiovale as a measure for noise. RESULTS: Ranking results in pooled data showed that the advanced noise filtering significantly improved the image quality in FLD as compared to LD images for all tested criteria. No significant differences in image quality were found between ND examinations and FLD. However, there was a notable inter-reader spread of the ranking. SD values were 15% higher for LD as compared to ND and FLD. CONCLUSION: The advanced noise filtering clearly improves image quality of CT examinations of the brain. This effect can be used to significantly lower radiation dose.
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- 1960
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5. ESR Essentials: basic physics of MR safety-practice recommendations by the European Society for Magnetic Resonance in Medicine and Biology.
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Nordin LE, Åberg K, Kihlberg J, Owman T, Hansson B, Björkman-Burtscher IM, Petersen C, and Lundberg P
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- Humans, Europe, Electromagnetic Fields, Risk Assessment, Societies, Medical, Magnetic Resonance Imaging methods, Magnetic Resonance Imaging adverse effects, Patient Safety
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Objectives: The use of magnetic resonance imaging (MRI) is safe from a long-term perspective since there are no known cumulative risks for patients or personnel. However, the technique comes with several acute risks associated with the powerful electromagnetic fields that are necessary to produce medical images. These risks include, among other things, a projectile hazard, loud noise, and the risk of heating. Safe use of MRI requires knowledge about the different hazards related to MRI and organizational structured work including the implementation of routines describing a safe workflow from the referral of a patient to the signed report. In this article, the risks associated with MRI are described along with suggestions for how each risk can be minimized or eliminated., Conclusion: The aim of this article is to provide support for the development of, and compliance with, MRI safety routines, and to work with the technique in a safe way. The scope of this treatise does not cover specific details of implant safety, however, the physical principles described can be applied to the risk assessment of implants., Key Points: Establish whether any MR contraindications apply to the patient. Evaluate means to deal with identified risks for both patients and personnel. It is imperative to always perform and document a risk-benefit assessment., Competing Interests: Compliance with ethical standards. Guarantor: The scientific guarantor of this publication is Peter Lundberg. Conflict of interest: The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article. Statistics and biometry: No complex statistical methods were necessary for this paper. Informed consent: Written informed consent was not required. Ethical approval: Institutional Review Board approval was not required. Study subjects or cohorts overlap: Not applicable. Methodology: Practice recommendations, (© 2024. The Author(s).)
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- 2025
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6. Nyquist ghost elimination for diffusion MRI by dual-polarity readout at low b-values.
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Jalnefjord O, Geades N, Gilbert G, Björkman-Burtscher IM, and Ljungberg M
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- Humans, Image Processing, Computer-Assisted methods, Adult, Anisotropy, Male, Brain diagnostic imaging, Female, Artifacts, Healthy Volunteers, Phantoms, Imaging, Diffusion Magnetic Resonance Imaging methods, Echo-Planar Imaging methods, Algorithms
- Abstract
Dual-polarity readout is a simple and robust way to mitigate Nyquist ghosting in diffusion-weighted echo-planar imaging but imposes doubled scan time. We here propose how dual-polarity readout can be implemented with little or no increase in scan time by exploiting an observed b-value dependence and signal averaging. The b-value dependence was confirmed in healthy volunteers with distinct ghosting at low b-values but of negligible magnitude at b = 1000 s/mm
2 . The usefulness of the suggested strategy was exemplified with a scan using tensor-valued diffusion encoding for estimation of parameter maps of mean diffusivity, and anisotropic and isotropic mean kurtosis, showing that ghosting propagated into all three parameter maps unless dual-polarity readout was applied. Results thus imply that extending the use of dual-polarity readout to low non-zero b-values provides effective ghost elimination and can be used without increased scan time for any diffusion MRI scan containing signal averaging at low b-values., (Creative Commons Attribution license.)- Published
- 2025
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7. Signal drift in diffusion MRI of the brain: effects on intravoxel incoherent motion parameter estimates.
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Jalnefjord O, Rosenqvist L, Warsame A, and Björkman-Burtscher IM
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- Humans, Adult, Reproducibility of Results, Male, Female, Artifacts, Healthy Volunteers, Retrospective Studies, Computer Simulation, Young Adult, Brain diagnostic imaging, Diffusion Magnetic Resonance Imaging methods, Diffusion Magnetic Resonance Imaging statistics & numerical data, Motion, Image Processing, Computer-Assisted methods, Algorithms
- Abstract
Objectives: Signal drift has been put forward as one of the fundamental confounding factors in diffusion MRI (dMRI) of the brain. This study characterizes signal drift in dMRI of the brain, evaluates correction methods, and exemplifies its impact on parameter estimation for three intravoxel incoherent motion (IVIM) protocols., Materials and Methods: dMRI of the brain was acquired in ten healthy subjects using protocols designed to enable retrospective characterization and correction of signal drift. All scans were acquired twice for repeatability analysis. Three temporal polynomial correction methods were evaluated: (1) global, (2) voxelwise, and (3) spatiotemporal. Effects of acquisition order were simulated using estimated drift fields., Results: Signal drift was around 2% per 5 min in the brain as a whole, but reached above 5% per 5 min in the frontal regions. Only correction methods taking spatially varying signal drift into account could achieve effective corrections. Altered acquisition order introduced both systematic changes and differences in repeatability in the presence of signal drift., Discussion: Signal drift in dMRI of the brain was found to be spatially varying, calling for correction methods taking this into account. Without proper corrections, choice of protocol can affect dMRI parameter estimates and their repeatability., Competing Interests: Declarations. Conflicts of interest: The authors have no conflicts of interest to declare. Ethical approval: The study was approved by the Swedish ethical review authority (Dnr 2020-00029). Informed consent: All subjects signed informed consent., (© 2024. The Author(s).)
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- 2024
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8. Cerebral Changes Following Carpal Tunnel Syndrome Treated with Guided Plasticity: A Prospective, Randomized, Placebo-Controlled Study.
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Flondell M, Mannfolk P, Rosén B, Björkman-Burtscher IM, and Björkman A
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Background Compression neuropathy, such as carpal tunnel syndrome (CTS), results in changed afferent nerve signaling, which may result in changes in somatosensory brain areas. The purpose of this study was to assess cerebral changes following unilateral CTS and to assess short-term and long-term cerebral effects of guided plasticity treatment using ipsilateral cutaneous forearm deafferentation. Methods Twenty-four patients with mild-to-moderate unilateral CTS were randomized to treatment with anesthetic cream (EMLA) or placebo. Patient-rated outcomes were assessed using Boston CTS questionnaire and disability of arm, shoulder, and hand questionnaire (QuickDASH). Patients were assessed for tactile discrimination and dexterity. Cortical activation during sensory stimulation was evaluated with functional magnetic resonance imaging at 3T. Assessments were performed at baseline, 90 minutes, and 8 weeks after treatment. Results Functional magnetic resonance imaging showed that sensory stimulation of the hand with CTS resulted in significantly less cortical activation in the primary somatosensory cortex (S1) than stimulation of the healthy hand. Treatment with cutaneous forearm deafferentation on the side with CTS resulted in increased cortical activation in S1 both after the initial treatment and following 8 weeks of treatment. In addition, QuickDASH and tactile discrimination showed improvement in the EMLA group over time. Conclusions Stimulation of median nerve-innervated fingers in patients with unilateral CTS results in smaller-than-normal activation in the contralateral S1. Cutaneous forearm anesthesia on the side with CTS results in larger activation in S1, suggesting recruitment of more neurons, and a slight improvement in sensory function., Competing Interests: Conflict of Interest None declared., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. ( https://creativecommons.org/licenses/by/4.0/ ).)
- Published
- 2024
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9. Normal Brain and Brain Tumor ADC: Changes Resulting From Variation of Diffusion Time and/or Echo Time in Pulsed-Gradient Spin Echo Diffusion Imaging.
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Johansson J, Lagerstrand K, Björkman-Burtscher IM, Laesser M, Hebelka H, and Maier SE
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- Humans, Male, Female, Adult, Middle Aged, Aged, Brain Neoplasms diagnostic imaging, Brain Neoplasms pathology, Diffusion Magnetic Resonance Imaging methods, Brain diagnostic imaging
- Abstract
Objectives: Increasing gradient performance on modern magnetic resonance imaging scanners has profoundly reduced the attainable diffusion and echo times for clinically available pulsed-gradient spin echo (PGSE) sequences. This study investigated how this may impact the measured apparent diffusion coefficient (ADC), which is considered an important diagnostic marker for differentiation between normal and abnormal brain tissue and for therapeutic follow-up., Materials and Methods: Diffusion time and echo time dependence of the ADC were evaluated on a high-performance 3 T magnetic resonance imaging scanner. Diffusion PGSE brain scans were performed in 10 healthy volunteers and in 10 brain tumor patients using diffusion times of 16, 40, and 70 ms, echo times of 60, 75, and 104 ms at 3 b-values (0, 100, and 1000 s/mm 2 ), and a maximum gradient amplitude of 68 mT/m. A low gradient performance system was also emulated by reducing the diffusion encoding gradient amplitude to 19 mT/m. In healthy subjects, the ADC was measured in 6 deep gray matter regions and in 6 white matter regions. In patients, the ADC was measured in the solid part of the tumor., Results: With increasing diffusion time, a small but significant ADC increase of up to 2.5% was observed for 6 aggregate deep gray matter structures. With increasing echo time or reduced gradient performance, a small but significant ADC decrease of up to 2.6% was observed for 6 aggregate white matter structures. In tumors, diffusion time-related ADC changes were inconsistent without clear trend. For tumors with diffusivity above 1.0 μm 2 /ms, with prolonged echo time, there was a pronounced ADC increase of up to 12%. Meanwhile, for tumors with diffusivity at or below 1.0 μm 2 /ms, no change or a reduction was observed. Similar results were observed for gradient performance reduction, with an increase of up to 21%. The coefficient of variation determined in repeat experiments was 2.4%., Conclusions: For PGSE and the explored parameter range, normal tissue ADC changes seem negligible. Meanwhile, observed tumor ADC changes can be relevant if ADC is used as a quantitative biomarker and not merely assessed by visual inspection. This highlights the importance of reporting all pertinent timing parameters in ADC studies and of considering these effects when building scan protocols for use in multicenter investigations., Competing Interests: Conflicts of interest and sources of funding: Financial support from Swedish Childhood Cancer Fund, funding under the agreement on medical education and research (ALFGBG 932648 to S.E.M., ALFGBG 966177 to I.M.B.-B.), the Swedish Research Council, and the Swedish Cancer Society., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)
- Published
- 2024
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10. Observations from the first 100 cases of intraoperative MRI - experiences, trends and short-term outcomes.
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Barchéus H, Peischl C, Björkman-Burtscher IM, Pettersson C, Smits A, Nilsson D, Farahmand D, Eriksson J, Skoglund T, and Corell A
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- Humans, Female, Adult, Retrospective Studies, Middle Aged, Male, Child, Adolescent, Aged, Young Adult, Treatment Outcome, Child, Preschool, Brain Neoplasms surgery, Brain Neoplasms diagnostic imaging, Monitoring, Intraoperative methods, Magnetic Resonance Imaging methods, Neurosurgical Procedures methods
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Background: We sought to analyze, in well-defined clinical setting, the first 100 patients treated at the intraoperative MRI (iMRI) hybrid surgical theatre at our facility in a population-based setting to evaluate which pathologies are best approached with iMRI assisted surgeries, as this is not yet clearly defined., Methods: Patients undergoing surgery in the 3T iMRI hybrid surgical theatre at our neurosurgical department between December 2017 to May 2021 were included after informed consent. Demographic, clinical, surgical, histological, radiological and outcome parameters, as well as variables related to iMRI, were retrospectively collected and analyzed. Patients were subdivided into adult and pediatric cohorts., Results: Various neurosurgical procedures were performed; resection of tumors and epileptic foci, endoscopic skull base procedures including pituitary lesions, deep brain stimulation (DBS) and laser interstitial thermal therapy (LITT). In total, 41 patients were pediatric. An iMRI scan was carried out in 96% of cases and led to continuation of surgery in 50% of cases, mainly due to visualized remaining pathological tissue (95.2%). Median time to iMRI from intubation was 280 min and median total duration of surgery was 445 min. The majority of patients experienced no postoperative complications (70%), 13 patients suffered permanent postoperative deficits, predominantly visual., Conclusion: Herein, we demonstrate the first 100 patients undergoing neurosurgery aided by iMRI at our facility since introduction. Indications for surgery differed between pediatric and adult patients. The iMRI was utilized for tumor surgeries, particularly adult low-grade gliomas and pediatric tumors, as well as for epilepsy surgery and DBS. In this heterogenous population, iMRI led to continuation of surgery in 50%. To establish the benefit in maximizing the extent of resection in these brain pathologies future studies are recommended., Clinical Trial Number: Not applicable., (© 2024. The Author(s).)
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- 2024
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11. Decrease of 7T MR short-term effects with repeated exposure.
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Hansson B, Garzón B, Lövdén M, and Björkman-Burtscher IM
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- Humans, Magnetic Resonance Imaging methods, Headache, Nausea, Dizziness, Movement
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Purpose: Although participants in 7 T magnetic resonance (MR) studies tolerate ultra-high field (UHF) well, subjectively experienced short-term effects, such as dizziness, inconsistent movement, nausea, or metallic taste, are reported. Evidence on subjectively experienced short-term effects in multiple exposures to UHF MR is scarce. The purpose of this study is to investigated experience of short-term effects, and occurrence of motion in healthy subjects exposed to seven weekly 7 T MR examinations., Methods: A questionnaire on short-term effects was completed by participants in an fMRI motor skill study. Seven UHF MR examinations were conducted over 7 weeks (exposure number: 1 to 7). Changes of experienced short-term effects were analyzed. Motion in fMRI images was quantified., Results: The questionnaire was completed 360 times by 67 participants after one to seven 7T MR examinations. Logistic mixed model analysis showed a significant association between dizziness, inconsistent movement, nausea, and headache and the examination numbers (p<0.03). Exposure to repeated examinations had no significant effect on peripheral nerve stimulation (PNS) or motion of the subjects. The overall experience of a 7T examination improved significantly (p<0.001) with increasing examination numbers., Conclusion: During multiple 7T examinations, subjects adapt to the strong static field. The short-term effects dizziness, inconsistent movement, nausea, and headache decrease over time as the MR sessions continue and experienced comfort increases. There was no significant difference in motion during the multiple fMRI examinations., (© 2024. The Author(s).)
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- 2024
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12. Extended treatment in cerebral ischemia score 2c or 3 as goal of successful endovascular treatment is associated with clinical benefit.
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Karlsson A, Jood K, Björkman-Burtscher IM, and Rentzos A
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- Humans, Aged, Goals, Treatment Outcome, Cerebral Infarction, Thrombectomy methods, Retrospective Studies, Brain Ischemia diagnostic imaging, Brain Ischemia surgery, Stroke diagnostic imaging, Stroke surgery, Endovascular Procedures methods
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Background and Purpose: Successful reperfusion, defined as a modified treatment in cerebral ischemia (mTICI) score 2b or 3, is an important goal for endovascular treatment (EVT) of stroke. Recently, an extension of the mTICI score with an additional grade 2c indicating near-complete reperfusion (expanded TICI, eTICI) and a revised definition of success as eTICI 2c or 3 were proposed. We evaluate whether eTICI 2c translates into improved clinical outcome compared to eTICI 2b., Material and Methods: Consecutive patients with large vessel occlusion in the anterior circulation who underwent EVT between December 2013 and December 2020 were included. Clinical outcome measures were favorable functional outcome at 90 days (modified Rankin Scale [mRS] scores 0 to 2 or return to pre-stroke mRS) and early neurological improvement (National Institutes of Health Stroke Scale [NIHSS] improvement ≥4 points or a score of 0-1 at 24 h)., Results: Of 1282 included patients (median age 76, median NIHSS 16), reperfusion was classified as eTICI 2b in 410 (32%), eTICI 2c in 242 (19%) and eTICI 3 in 464 (36%). eTICI 2c differed significally from 2b with respect to early neurological improvement (aOR = 1.49, 95% CI = 1.01-2.19). No statistically significant difference in favorable functional outcome at 90 days was found (eTICI 2c vs 2b, aOR = 1.31, 95% CI = 0.88-2.00)., Conclusion: Our study indicates early clinical benefit at 24 h of achieving eTICI 2c compared to eTICI 2b, but no significant difference was seen in favorable functional outcome at 90 days. Our results support eTICI 2c and 3 as the goal of a successful thrombectomy but do not exclude eTICI 2b as an acceptable result., Competing Interests: Declaration of Competing Interest All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest or non-financial interest in the subject matter or materials discussed in this manuscript., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)
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- 2024
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13. Comparison of the patient-derived modified Japanese Orthopaedic Association scale and the European myelopathy score.
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de Dios E, Löfgren H, Laesser M, Lindhagen L, Björkman-Burtscher IM, and MacDowall A
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- Humans, Female, Middle Aged, Male, Cohort Studies, Treatment Outcome, Japan, Prospective Studies, Cervical Vertebrae surgery, Severity of Illness Index, Orthopedics, Spinal Cord Diseases diagnosis, Spinal Cord Diseases surgery
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Purpose: To compare the patient-derived modified Japanese Orthopaedic Association (P-mJOA) scale with the European myelopathy score (EMS) for the assessment of patients with degenerative cervical myelopathy (DCM)., Methods: In this register-based cohort study with prospectively collected data, included patients were surgically treated for DCM and had reported both P-mJOA and EMS scores at baseline, 1-year follow-up, and/or 2-year follow-up to the Swedish Spine Register. P-mJOA and EMS scores were defined as severe (P-mJOA 0-11 and EMS 5-8), moderate (P-mJOA 12-14 and EMS 9-12), or mild (P-mJOA 15-18 and EMS 13-18). P-mJOA and EMS mean scores were compared, and agreement was evaluated with Spearman's rank correlation coefficient (ρ), the intraclass correlation coefficient (ICC), and kappa (κ) statistics., Results: Included patients (n = 714, mean age 63.2 years, 42.2% female) completed 937 pairs of the P-mJOA and the EMS. The mean P-mJOA and EMS scores were 13.9 ± 3.0 and 14.5 ± 2.7, respectively (mean difference -0.61 [95% CI -0.72 to -0.51; p < 0.001]). Spearman's ρ was 0.84 (p < 0.001), and intra-rater agreement measured with ICC was 0.83 (p < 0.001). Agreement of severity level measured with unweighted and weighted κ was fair (κ = 0.22 [p < 0.001]; κ = 0.34 [p < 0.001], respectively). Severity levels were significantly higher using the P-mJOA (p < 0.001)., Conclusion: The P-mJOA and the EMS had similar mean scores, and intra-rater agreement was high, whereas severity levels only demonstrated fair agreement. The EMS has a lower sensitivity for detecting severe myelopathy but shows an increasing agreement with the P-mJOA for milder disease severity. A larger interval to define severe myelopathy with the EMS is recommended., (© 2023. The Author(s).)
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- 2024
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14. Evaluation of a Fully Automated Method for Ventricular Volume Segmentation Before and After Shunt Surgery in Idiopathic Normal Pressure Hydrocephalus.
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Ziegelitz D, Hellström P, Björkman-Burtscher IM, Agerskov S, Stevens-Jones O, Farahmand D, and Tullberg M
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- Humans, Retrospective Studies, Treatment Outcome, Cerebral Ventricles diagnostic imaging, Cerebral Ventricles surgery, Cerebral Ventricles pathology, Ventriculoperitoneal Shunt methods, Magnetic Resonance Imaging methods, Hydrocephalus, Normal Pressure diagnostic imaging, Hydrocephalus, Normal Pressure surgery, Hydrocephalus, Normal Pressure pathology, Cardiovascular Abnormalities pathology, Cardiovascular Abnormalities surgery
- Abstract
Background: Determination of the ventricle size in idiopathic normal pressure hydrocephalus (iNPH) is essential for diagnosis and follow-up of shunt results. Fully automated segmentation methods are anticipated to optimize the accuracy and time efficiency of ventricular volume measurements. We evaluated the accuracy of preoperative and postoperative ventricular volume measurements in iNPH by a magnetic resonance imaging (MRI)-based licensed software for fully automated quantitative assessment., Methods: Forty-eight patients diagnosed with iNPH were retrospectively analyzed. All patients received a ventriculoperitoneal shunt and had symptom grading and routine MRI preoperatively and 3-6 months postoperatively. Ventricular volumes, generated by fully automated T1-weighted imaging volume sequence segmentation, were compared with semiautomatic measurements and routine radiologic reports. The relation of postoperative ventricular size change to clinical response was evaluated., Results: Fully automated segmentation was achieved in 95% of the MRIs, but showed various rates of 8 minor segmentation errors. The correlation between both segmentation methods was very strong (r >0.9) and the agreement very good using Bland-Altman analyses. The ventricular volumes differed significantly between semiautomated and fully automated segmentations and between preoperative and postoperative MRI. The fully automated method systematically overestimated the ventricles by a median 15 mL preoperatively and 14 mL postoperatively; hence, the magnitudes of volume changes were equivalent. Routine radiologic reports of ventricular size changes were inaccurate in 51% and lacked association with treatment response. Objectively measured ventricular volume changes correlated moderately with postoperative clinical improvement., Conclusions: A fully automated volumetric method permits reliable evaluation of preoperative ventriculomegaly and postoperative ventricular volume change in idiopathic normal pressure hydrocephalus., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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15. Trust and stakeholder perspectives on the implementation of AI tools in clinical radiology.
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Bergquist M, Rolandsson B, Gryska E, Laesser M, Hoefling N, Heckemann R, Schneiderman JF, and Björkman-Burtscher IM
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- Humans, Artificial Intelligence, Reproducibility of Results, Trust, Radiology
- Abstract
Objectives: To define requirements that condition trust in artificial intelligence (AI) as clinical decision support in radiology from the perspective of various stakeholders and to explore ways to fulfil these requirements., Methods: Semi-structured interviews were conducted with twenty-five respondents-nineteen directly involved in the development, implementation, or use of AI applications in radiology and six working with AI in other areas of healthcare. We designed the questions to explore three themes: development and use of AI, professional decision-making, and management and organizational procedures connected to AI. The transcribed interviews were analysed in an iterative coding process from open coding to theoretically informed thematic coding., Results: We identified four aspects of trust that relate to reliability, transparency, quality verification, and inter-organizational compatibility. These aspects fall under the categories of substantial and procedural requirements., Conclusions: Development of appropriate levels of trust in AI in healthcare is complex and encompasses multiple dimensions of requirements. Various stakeholders will have to be involved in developing AI solutions for healthcare and radiology to fulfil these requirements., Clinical Relevance Statement: For AI to achieve advances in radiology, it must be given the opportunity to support, rather than replace, human expertise. Support requires trust. Identification of aspects and conditions for trust allows developing AI implementation strategies that facilitate advancing the field., Key Points: • Dimensions of procedural and substantial demands that need to be fulfilled to foster appropriate levels of trust in AI in healthcare are conditioned on aspects related to reliability, transparency, quality verification, and inter-organizational compatibility. •Creating the conditions for trust to emerge requires the involvement of various stakeholders, who will have to compensate the problem's inherent complexity by finding and promoting well-defined solutions., (© 2023. The Author(s).)
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- 2024
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16. Probing brain tissue microstructure with MRI: principles, challenges, and the role of multidimensional diffusion-relaxation encoding.
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Lampinen B, Szczepankiewicz F, Lätt J, Knutsson L, Mårtensson J, Björkman-Burtscher IM, van Westen D, Sundgren PC, Ståhlberg F, and Nilsson M
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- Humans, Magnetic Resonance Imaging methods, Gray Matter diagnostic imaging, Diffusion Magnetic Resonance Imaging methods, Anisotropy, Brain diagnostic imaging, Brain pathology, White Matter diagnostic imaging, White Matter pathology
- Abstract
Diffusion MRI uses the random displacement of water molecules to sensitize the signal to brain microstructure and to properties such as the density and shape of cells. Microstructure modeling techniques aim to estimate these properties from acquired data by separating the signal between virtual tissue 'compartments' such as the intra-neurite and the extra-cellular space. A key challenge is that the diffusion MRI signal is relatively featureless compared with the complexity of brain tissue. Another challenge is that the tissue microstructure is wildly different within the gray and white matter of the brain. In this review, we use results from multidimensional diffusion encoding techniques to discuss these challenges and their tentative solutions. Multidimensional encoding increases the information content of the data by varying not only the b-value and the encoding direction but also additional experimental parameters such as the shape of the b-tensor and the echo time. Three main insights have emerged from such encoding. First, multidimensional data contradict common model assumptions on diffusion and T
2 relaxation, and illustrates how the use of these assumptions cause erroneous interpretations in both healthy brain and pathology. Second, many model assumptions can be dispensed with if data are acquired with multidimensional encoding. The necessary data can be easily acquired in vivo using protocols optimized to minimize Cramér-Rao lower bounds. Third, microscopic diffusion anisotropy reflects the presence of axons but not dendrites. This insight stands in contrast to current 'neurite models' of brain tissue, which assume that axons in white matter and dendrites in gray matter feature highly similar diffusion. Nevertheless, as an axon-based contrast, microscopic anisotropy can differentiate gray and white matter when myelin alterations confound conventional MRI contrasts., Competing Interests: Declaration of Competing Interest Markus Nilsson and Filip Szczepankiewicz declare ownership interests in Random Walk Imaging, which holds patents pertaining to the methods presented herein. Remaining authors declare no conflict of interest., (Copyright © 2023. Published by Elsevier Inc.)- Published
- 2023
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17. MRI-based measurements of spondylolisthesis and kyphosis in degenerative cervical myelopathy.
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de Dios E, Laesser M, Björkman-Burtscher IM, Lindhagen L, and MacDowall A
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- Humans, Reproducibility of Results, Cervical Vertebrae pathology, Magnetic Resonance Imaging, Spondylolisthesis complications, Spondylolisthesis diagnostic imaging, Spondylolisthesis pathology, Kyphosis diagnostic imaging, Kyphosis pathology, Spinal Cord Diseases pathology
- Abstract
Background: To provide normative data and to determine accuracy and reliability of preoperative measurements of spondylolisthesis and kyphosis on supine static magnetic resonance imaging (MRI) of patients with degenerative cervical myelopathy., Methods: T2-weighted midsagittal images of the cervical spine were in 100 cases reviewed twice by one junior observer, with an interval of 3 months, and once by a senior observer. The spondylolisthesis slip (SSlip, mm) and the modified K-line interval (mK-line INT, mm) were assessed for accuracy with the standard error of measurement (SEm) and the minimum detectable change (MDC). Intraobserver and interobserver reliability levels were determined using the intraclass correlation coefficient (ICC)., Results: The SEm was 0.5 mm (95% CI 0.4-0.6) for spondylolisthesis and 0.6 mm (95% CI 0.5-0.7) for kyphosis. The MDC, i.e., the smallest difference between two examinations that can be detected with statistical certainty, was 1.5 mm (95% CI 1.2-1.8) for spondylolisthesis and 1.6 mm (95% CI 1.3-1.8) for kyphosis. The highest reliability levels were seen between the second observation of the junior examiner and the senior observer (ICC = 0.80 [95% CI 0.70-0.87] and ICC = 0.96 [95% CI 0.94-0.98] for SSlip and mK-line INT, respectively)., Conclusions: This study provides normative values of alignment measurements of spondylolisthesis and kyphosis in DCM patients. It further shows the importance of taking measurement errors into account when defining cut-off values for cervical deformity parameters and their potential clinical application in surgical decision-making., (© 2023. The Author(s).)
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- 2023
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18. Circulating Brain Injury Biomarkers: A Novel Method for Quantification of the Impact on the Brain After Tumor Surgery.
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Michaëlsson I, Hallén T, Carstam L, Laesser M, Björkman-Burtscher IM, Sörbo A, Blennow K, Zetterberg H, Jakola AS, and Skoglund T
- Subjects
- Adult, Humans, Prospective Studies, Neurofilament Proteins metabolism, tau Proteins metabolism, Brain pathology, Biomarkers, Glial Fibrillary Acidic Protein metabolism, Brain Injuries, Glioma pathology
- Abstract
Background: Clinical methods to quantify brain injury related to neurosurgery are scarce. Circulating brain injury biomarkers have recently gained increased interest as new ultrasensitive measurement techniques have enabled quantification of brain injury through blood sampling., Objective: To establish the time profile of the increase in the circulating brain injury biomarkers glial fibrillary acidic protein (GFAP), tau, and neurofilament light (NfL) after glioma surgery and to explore possible relationships between these biomarkers and outcome regarding volume of ischemic injury identified with postoperative MRI and new neurological deficits., Methods: In this prospective study, 34 adult patients scheduled for glioma surgery were included. Plasma concentrations of brain injury biomarkers were measured the day before surgery, immediately after surgery, and on postoperative days 1, 3, 5, and 10., Results: Circulating brain injury biomarkers displayed a postoperative increase in the levels of GFAP ( P < .001), tau ( P < .001), and NfL ( P < .001) on Day 1 and a later, even higher, peak of NFL at Day 10 ( P = .028). We found a correlation between the increased levels of GFAP, tau, and NfL on Day 1 after surgery and the volume of ischemic brain tissue on postoperative MRI. Patients with new neurological deficits after surgery had higher levels of GFAP and NfL on Day 1 compared with those without new neurological deficits., Conclusion: Measuring circulating brain injury biomarkers could be a useful method for quantification of the impact on the brain after tumor surgery or neurosurgery in general., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)
- Published
- 2023
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19. Postnatal serum IGF-1 levels associate with brain volumes at term in extremely preterm infants.
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Hellström W, Hortensius LM, Löfqvist C, Hellgren G, Tataranno ML, Ley D, Benders MJNL, Hellström A, Björkman-Burtscher IM, Heckemann RA, and Sävman K
- Subjects
- Infant, Humans, Infant, Newborn, Vascular Endothelial Growth Factor A metabolism, Brain, Gray Matter metabolism, Gestational Age, Magnetic Resonance Imaging methods, Infant, Extremely Premature, Insulin-Like Growth Factor I metabolism
- Abstract
Background: Growth factors important for normal brain development are low in preterm infants. This study investigated the link between growth factors and preterm brain volumes at term., Material/methods: Infants born <28 weeks gestational age (GA) were included. Endogenous levels of insulin-like growth factor (IGF)-1, brain-derived growth factor, vascular endothelial growth factor, and platelet-derived growth factor (expressed as area under the curve [AUC] for serum samples from postnatal days 1, 7, 14, and 28) were utilized in a multivariable linear regression model. Brain volumes were determined by magnetic resonance imaging (MRI) at term equivalent age., Results: In total, 49 infants (median [range] GA 25.4 [22.9-27.9] weeks) were included following MRI segmentation quality assessment and AUC calculation. IGF-1 levels were independently positively associated with the total brain (p < 0.001, β = 0.90), white matter (p = 0.007, β = 0.33), cortical gray matter (p = 0.002, β = 0.43), deep gray matter (p = 0.008, β = 0.05), and cerebellar (p = 0.006, β = 0.08) volume adjusted for GA at birth and postmenstrual age at MRI. No associations were seen for other growth factors., Conclusions: Endogenous exposure to IGF-1 during the first 4 weeks of life was associated with total and regional brain volumes at term. Optimizing levels of IGF-1 might improve brain growth in extremely preterm infants., Impact: High serum levels of insulin-like growth factor (IGF)-1 during the first month of life were independently associated with increased total brain volume, white matter, gray matter, and cerebellar volume at term equivalent age in extremely preterm infants. IGF-1 is a critical regulator of neurodevelopment and postnatal levels are low in preterm infants. The effects of IGF-1 levels on brain development in extremely preterm infants are not fully understood. Optimizing levels of IGF-1 may benefit early brain growth in extremely preterm infants. The effects of systemically administered IGF-1/IGFBP3 in extremely preterm infants are now being investigated in a randomized controlled trial (Clinicaltrials.gov: NCT03253263)., (© 2022. The Author(s).)
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- 2023
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20. Improvement rates, adverse events and predictors of clinical outcome following surgery for degenerative cervical myelopathy.
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de Dios E, Laesser M, Björkman-Burtscher IM, Lindhagen L, and MacDowall A
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- Humans, Female, Male, Treatment Outcome, Laminectomy adverse effects, Reoperation, Cervical Vertebrae surgery, Spinal Cord Diseases surgery, Spinal Cord Diseases etiology
- Abstract
Purpose: To investigate improvement rates, adverse events and predictors of clinical outcome after laminectomy alone (LAM) or laminectomy with instrumented fusion (LAM + F) for degenerative cervical myelopathy (DCM)., Methods: This is a post hoc analysis of a previously published DCM cohort. Improvement rates for European myelopathy score (EMS) and Neck Disability Index (NDI) at 2- and 5-year follow-ups and adverse events are presented descriptively for available cases. Predictor endpoints were EMS and NDI scores at follow-ups, surgeon- and patient-reported complications, and reoperation-free interval. For predictors, univariate and multivariable models were fitted to imputed data., Results: Mean age of patients (LAM n = 412; LAM + F n = 305) was 68 years, and 37.4% were women. LAM + F patients had more severe spondylolisthesis and less severe kyphosis at baseline, more surgeon-reported complications, more patient-reported complications, and more reoperations (p ≤ 0.05). After imputation, the overall EMS improvement rate was 43.8% at 2 years and 36.3% at 5 years. At follow-ups, worse EMS scores were independent predictors of worse EMS outcomes and older age and worse NDI scores were independent predictors of worse NDI outcomes. LAM + F was associated with more surgeon-reported complications (ratio 1.81; 95% CI 1.17-2.80; p = 0.008). More operated levels were associated with more patient-reported complications (ratio 1.12; 95% CI 1.02-1.22; p = 0.012) and a shorter reoperation-free interval (hazard ratio 1.30; 95% CI 1.08-1.58; p = 0.046)., Conclusions: These findings suggest that surgical intervention at an earlier myelopathy stage might be beneficial and that less invasive procedures are preferable in this patient population., (© 2022. The Author(s).)
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- 2022
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21. Health effects related to exposure of static magnetic fields and acoustic noise-comparison between MR and CT radiographers.
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Glans A, Wilén J, Lindgren L, Björkman-Burtscher IM, and Hansson B
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- Humans, Acoustics, Cross-Sectional Studies, Dizziness epidemiology, Illusions etiology, Magnetic Resonance Imaging, Nausea epidemiology, Surveys and Questionnaires, Taste Disorders epidemiology, Tomography, X-Ray Computed, Vertigo epidemiology, Sweden epidemiology, Male, Female, Magnetic Fields adverse effects, Occupational Exposure adverse effects, Noise, Occupational adverse effects, Radiography, Occupational Diseases epidemiology
- Abstract
Objectives: We explored the prevalence of health complaints subjectively associated with static magnetic field (SMF) and acoustic noise exposure among MR radiographers in Sweden, using CT radiographers as a control group. Additionally, we explored radiographers' use of strategies to mitigate adverse health effects., Methods: A cross-sectional survey was sent to all hospitals with MR units in Sweden. MR and/or CT personnel reported prevalence and attribution of symptoms (vertigo/dizziness, nausea, metallic taste, illusion of movement, ringing sensations/tinnitus, headache, unusual drowsiness/tiredness, forgetfulness, difficulties concentrating, and difficulties sleeping) within the last year. We used logistic regression to test associations between sex, age, stress, SMF strength, working hours, and symptom prevalence. Data regarding hearing function, work-environmental noise, and strategies to mitigate adverse symptoms were also analysed., Results: In total, 529 out of 546 respondents from 86 hospitals were eligible for participation. A ≥ 20 working hours/week/modality cut-off rendered 342 participants grouped into CT (n = 75), MR (n = 121), or mixed personnel (n = 146). No significant differences in symptom prevalence were seen between groups. Working at ≥ 3T increased SMF-associated symptoms as compared with working at ≤ 1.5T (OR: 2.03, CI
95 : 1.05-3.93). Stress was a significant confounder. Work-related noise was rated as more troublesome by CT than MR personnel (p < 0.01). MR personnel tended to use more strategies to mitigate adverse symptoms., Conclusion: No significant differences in symptom prevalence were seen between MR and CT radiographers. However, working at 3T increased the risk of SMF symptoms, and stress increased adverse health effects. Noise nuisance was considered more problematic by CT than MR personnel., Key Points: • No significant differences in symptom prevalence were seen between MR and CT radiographers. • Working at ≥ 3 T doubled the odds of experiencing SMF symptoms (vertigo/dizziness, nausea, metallic taste, and/or illusion of movement) as compared to working exclusively at ≤ 1.5 T. • Work-related acoustic noise was less well mitigated and was rated as more troublesome by CT personnel than by MR personnel., (© 2022. The Author(s).)- Published
- 2022
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22. Structural association between heterotopia and cortical lesions visualised with 7 T MRI in patients with focal epilepsy.
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Zampeli A, Hansson B, Bloch KM, Englund E, Källén K, Strandberg MC, and Björkman-Burtscher IM
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- Humans, Imaging, Three-Dimensional methods, Magnetic Resonance Imaging methods, Epilepsies, Partial diagnostic imaging, Epilepsies, Partial pathology, Epilepsy diagnostic imaging, Epilepsy pathology, Malformations of Cortical Development diagnostic imaging, Malformations of Cortical Development pathology
- Abstract
Purpose: To analyze structural characteristics of malformations of cortical development (MCD) at 7T and 3T MRI., Methods: Twenty-five patients were examined with a 7T MRI-scanner in addition to 3T examinations performed for epilepsy evaluation. 7T sequences included a 3D-T1-weighted (T1w) MPRAGE, 3D-T2w FLAIR, and heavily T2w axial and coronal high-resolution (0.5 × 0.5 × 0.75-1.0 mm
3 ) 2D-TSE sequences. Images were reviewed for 7T MRI imaging characteristics of MCD, visibility and frequency of identified lesions on 7T and on 3T (original reports and second reading)., Results: In 25 patients 112 lesions were identified (57 gray matter (GM) heterotopia, 37 focal cortical dysplasia (FCD), and 18 other MCD). Imaging characteristics of the 37 FCD were cortical thickening (n = 11); GM-WM border blurring (n = 30); GM signal intensity changes (n = 18); juxtacortical WM signal intensity changes (n = 18); and transmantle WM signal intensity changes (n = 11). None of the 7T MRI sequences was sufficient to detect all types of lesions. Heterotopia were in general isointense to normal GM. Structural associations between 36 heterotopia and overlaying cortex were observed, composed either of a direct connection, vessel-like structures, or GM-like bridges. FCD were mentioned in 30% (11 of 37) of the original reports at 3T, and in 57% (21 of 37) after second reading. FCD connections to subcortical heterotopia were clinically not reported at all., Conclusion: 7T MRI revealed subtle connections between heterotopia and previous unidentified pathology in overlaying cortex. These findings may be significant for the understanding of the anatomical seizure origin and propagation pathways., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)- Published
- 2022
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23. MR-safety in clinical practice at 7T: Evaluation of a multistep screening process in 1819 subjects.
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Hansson B, Simic M, Olsrud J, Markenroth Bloch K, Owman T, Sundgren PC, and Björkman-Burtscher IM
- Subjects
- Humans, Magnetic Resonance Imaging methods
- Abstract
Introduction: MR facilities must implement and maintain adequate screening and safety procedures to ensure safety during MR examinations. The aim of this study was to evaluate a multi-step MR safety screening process used at a 7T facility regarding incidence of different types of safety risks detected during the safety procedure., Methods: Subjects scheduled for an MR examination and having entered the 7T facility during 2016-2019 underwent a pre-defined multi-step MR safety screening process. Screening documentation of 1819 included subjects was reviewed, and risks identified during the different screening steps were compiled. These data were also related to documented decisions made by a 7T MR safety committee and reported MR safety incidents., Results: Passive or active implants (n = 315) were identified in a screening form and/or an additional documented interview in 305 subjects. Additional information not previously self-reported by the subject, regarding implants necessitating safety decisions performed by the staff was revealed in the documented interview in 102 subjects (106 items). In total, the 7T MR safety committee documented a decision in 36 (2%) of the included subjects. All of these subjects were finally cleared for scanning., Conclusion: A multi-step screening process allows a thorough MR screening of subjects, avoiding safety incidents. Different steps in the process allow awareness to rise and items to be detected that were missed in earlier steps., Implications for Practice: Safety questions posed at a single timepoint during an MR screening process might not reveal all safety risks. Repetition and rephrasing of screening questions leads to increased detection of safety risks. This could be effectively mitigated by a multi-step screening process. A multi-disciplinary safety committee is efficient at short notice responding to unexpected safety issues., Competing Interests: Conflict of interest statement The authors have no conflict of interest in accordance with the journals guidelines., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
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- 2022
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24. Visualization of wrist ligaments with 3D and 2D magnetic resonance imaging at 3 Tesla.
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Götestrand S, Björkman A, Björkman-Burtscher IM, Ab-Fawaz R, Kristiansson I, Lundin B, and Geijer M
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- Adult, Female, Humans, Imaging, Three-Dimensional, Male, Middle Aged, Prospective Studies, Triangular Fibrocartilage diagnostic imaging, Young Adult, Ligaments, Articular diagnostic imaging, Magnetic Resonance Imaging methods, Wrist Joint diagnostic imaging
- Abstract
Background: Wrist ligaments are challenging to visualize using magnetic resonance imaging (MRI). Injuries involving the scapholunate ligament (SLL), the lunotriquetral ligament (LTL), and the triangular fibrocartilage complex (TFCC) are common and difficult to diagnose, often requiring diagnostic arthroscopy., Purpose: To compare the visualization of wrist ligaments on a three-dimensional (3D) sequence with two-dimensional (2D) sequences on 3-T MRI., Material and Methods: Eighteen healthy volunteers were examined with a 3D SPACE (sampling perfection with application optimized contrasts using different flip angle evolution) sequence and 2D coronal, axial, and sagittal proton density-weighted (PD) sequences. Four musculoskeletal radiologists graded the anatomical visibility of the SLL, LTL, TFCC, and the image quality, using five grades in a visual grading characteristics (VGC) evaluation. After Bonferroni correction, a P value ≤0.005 was considered statistically significant., Results: The 3D images were graded significantly better than the 2D images in the visualization of the dorsal and palmar parts of the SLL and the LTL. Regarding the TFCC, the 3D images were graded significantly better for visualization of the foveal attachment. 2D imaging was not found significantly superior to 3D imaging in any aspect., Conclusion: The 3D SPACE sequence was scored as superior to the 2D sequences at 3 T in the assessment of the SLL, the LTL, and the foveal attachment of the TFCC. Thus, 3D SPACE can replace 2D PD sequences when these ligaments need to be assessed.
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- 2022
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25. Visualization of wrist anatomy-a comparison between 7T and 3T MRI.
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Götestrand S, Björkman A, Björkman-Burtscher IM, Kristiansson I, Aksyuk E, Szaro P, Markenroth Bloch K, and Geijer M
- Subjects
- Adult, Female, Humans, Imaging, Three-Dimensional, Magnetic Resonance Imaging, Male, Middle Aged, Wrist Joint diagnostic imaging, Young Adult, Wrist diagnostic imaging, Wrist Injuries
- Abstract
Objective: Injuries to the wrist are, due to its small size and complex anatomical structures, difficult to assess by MR, and surgical interventions such as diagnostic arthroscopy are often necessary. Therefore, improved visualization using non-invasive methods could be of clinical value. As a first step of improvement, the purpose of this study was to evaluate visualization of anatomical structures at 7T compared with 3T MR., Methods: Eighteen healthy volunteers (three males and three females from each age decade between 20 and 49 years) were examined with 7T and 3T MR. Four musculoskeletal radiologists graded 2D and 3D images on a five-level grading scale for visibility of ligaments, cartilage, nerves, trabecular bone, and tendons, as well as overall image quality (i.e., edge sharpness, perceived tissue contrast, and presence of artefacts). Statistical analysis was done using a visual grading characteristics (VGC) analysis., Results: Visibility of cartilage, trabecular bone, tendons, nerves, and ligaments was graded significantly higher at 7T with an area under the curve (AUC
VGC ) of 0.62-0.88 (95% confidence interval [CI] 0.50-0.97, p = < 0.0001-0.03) using either 2D or 3D imaging. Imaging with 3T was not graded as superior to 7T for any structure. Image quality was also significantly superior at 7T, except for artefacts, where no significant differences were found., Conclusions: Tendons, trabecular bone, nerves, and ligaments were all significantly better visualized at 7T compared to 3T., Key Points: • MRI of the wrist at 7T with a commercially available wrist coil is feasible at similar acquisition times as for 3T MRI. • The current study showed 7T to be superior to 3T in the visualization of anatomical structures of the wrist, including ligaments, tendons, nerves, and trabecular bone. • Image quality was significantly superior at 7T, except for artefacts, where no significant differences were found., (© 2021. The Author(s).)- Published
- 2022
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26. Inter-modality assessment of medial temporal lobe atrophy in a non-demented population: application of a visual rating scale template across radiologists with varying clinical experience.
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Håkansson C, Tamaddon A, Andersson H, Torisson G, Mårtensson G, Truong M, Annertz M, Londos E, Björkman-Burtscher IM, Hansson O, and van Westen D
- Subjects
- Aged, Atrophy pathology, Humans, Magnetic Resonance Imaging, Radiologists, Temporal Lobe diagnostic imaging, Temporal Lobe pathology, Alzheimer Disease pathology, Cognitive Dysfunction pathology
- Abstract
Objectives: To assess inter-modality agreement and accuracy for medial temporal lobe atrophy (MTA) ratings across radiologists with varying clinical experience in a non-demented population., Methods: Four raters (two junior radiologists and two senior neuroradiologists) rated MTA on CT and MRI scans using Scheltens' MTA scale. Ratings were compared to a consensus rating by two experienced neuroradiologists for estimation of true positive and negative rates (TPR and TNR) and over- and underestimation of MTA. Inter-modality agreement expressed as Cohen's κ (dichotomized data), Cohen's κ
w , and two-way mixed, single measures, consistency ICC (ordinal data) were determined. Adequate agreement was defined as κ/κw ≥ 0.80 and ICC ≥ 0.80 (significance level at 95% CI ≥ 0.65)., Results: Forty-nine subjects (median age 72 years, 27% abnormal MTA) with cognitive impairment were included. Only junior radiologists achieved adequate agreement expressed as Cohen's κ. All raters achieved adequate agreement expressed as Cohen's κw and ICC. True positive rates varied from 69 to 100% and TNR varied from 85 to 100%. No under- or overestimation of MTA was observed. Ratings did not differ between radiologists., Conclusion: We conclude that radiologists with varying experience achieve adequate inter-modality agreement and similar accuracy when Scheltens' MTA scale is used to rate MTA on a non-demented population. However, TPR varied between radiologists which could be attributed to rating style differences., Key Points: • Radiologists with varying experience achieve adequate inter-modality agreement with similar accuracy when Scheltens' MTA scale is used to rate MTA on a non-demented population. • Differences in rating styles might affect accuracy, this was most evident for senior neuroradiologists, and only junior radiologists achieved adequate agreement on dichotomized (abnormal/normal) ratings. • The use of an MTA scale template might compensate for varying clinical experience which could make it applicable for clinical use., (© 2021. The Author(s).)- Published
- 2022
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27. Spinal cord compression in relation to clinical symptoms in patients with spinal meningiomas.
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Corell A, Cerbach C, Hoefling N, Björkman-Burtscher IM, and Jakola AS
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- Aged, Female, Humans, Logistic Models, Magnetic Resonance Imaging, Male, Meningeal Neoplasms complications, Meningeal Neoplasms diagnostic imaging, Meningioma complications, Meningioma diagnostic imaging, Middle Aged, Retrospective Studies, Spinal Cord Compression diagnostic imaging, Spinal Cord Compression surgery, Symptom Assessment, Treatment Outcome, Meningeal Neoplasms pathology, Meningioma pathology, Spinal Cord Compression etiology
- Abstract
Objective: Spinal meningiomas are common primary tumors of the spinal canal and the resulting spinal cord compression (SCC) is intrinsically related to symptoms and outcome, but literature concerning this association is limited. We aimed to present data on both degree of SCC and tumor occupancy percentage in relation to neurological symptoms and outcome., Methods: Patients ≥ 18 years with a histological diagnosis of spinal canal meningioma treated between 2000 and 2017 were retrospectively evaluated for symptoms and neurological outcome in relation to SCC (i.e. compression of spinal cord at maximal tumor compression compared to maximum area above/below compression) and tumor occupancy percentage (percentage of dural sac area occupied by tumor at maximal tumor compression). Area segmentation of spinal cord, tumor and dural sac (as marker of spinal canal) was performed manually on magnetic resonance imaging (MRI) scans. The neurological deficit was assessed pre- and postoperatively according to the McCormick score. A logistic regression was made with a training set to identify the cut-off level for motor deficit., Results: The cohort included 111 patients with a mean age of 62.5 years and 77.5% were female. The dominating symptoms preoperatively were sensory disturbance (91.0%), motor deficit (80.2%) and gait disturbance (67.6%). Postoperatively 53.2% of patients, also in some of those with severe deficit and high tumor occupancy, improved their neurological deficit and 43.2% were unchanged. Patients with intradural meningioma and assessable MRI scans were included to evaluate SCC (n = 83). The mean extent of SCC was 50.6%. Exploration of tumor occupancy percentage identified a cut-off at 65% tumor occupancy to best discriminate between patients with or without motor deficit., Conclusion: Patients with an intradural tumor occupancy percentage of > 65% are more likely to have a preoperative symptom and deficit, validating previous findings. Therefore, we suggest that even in asymptomatic, otherwise fit, patients with tumor occupancy approaching 65% should be considered for surgery since there is a high risk of developing deficit with even minimal growth. Concerning recovery, patients with tumor both high tumor occupancy and significantly impaired function tended to improve their functional level postoperatively., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2021
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28. Serum docosahexaenoic acid levels are associated with brain volumes in extremely preterm born infants.
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Hortensius LM, Hellström W, Sävman K, Heckemann RA, Björkman-Burtscher IM, Groenendaal F, Andersson MX, Nilsson AK, Tataranno ML, van Elburg RM, Hellström A, and Benders MJNL
- Subjects
- Arachidonic Acid, Cohort Studies, Female, Gestational Age, Humans, Infant, Newborn, Male, Organ Size, Brain anatomy & histology, Docosahexaenoic Acids blood, Infant, Extremely Premature
- Abstract
Background: Docosahexaenoic acid (DHA) and arachidonic acid (AA) are important for fetal brain growth and development. Our aim was to evaluate the association between serum DHA and AA levels and brain volumes in extremely preterm infants., Methods: Infants born at <28 weeks gestational age in 2013-2015, a cohort derived from a randomized controlled trial comparing two types of parenteral lipid emulsions, were included (n = 90). Serum DHA and AA levels were measured at postnatal days 1, 7, 14, and 28, and the area under the curve was calculated. Magnetic resonance (MR) imaging was performed at term-equivalent age (n = 66), and volumes of six brain regions were automatically generated., Results: After MR image quality assessment and area under the curve calculation, 48 infants were included (gestational age mean [SD] 25.5 [1.4] weeks). DHA levels were positively associated with total brain (B = 7.966, p = 0.012), cortical gray matter (B = 3.653, p = 0.036), deep gray matter (B = 0.439, p = 0.014), cerebellar (B = 0.932, p = 0.003), and white matter volume (B = 3.373, p = 0.022). AA levels showed no association with brain volumes., Conclusions: Serum DHA levels during the first 28 postnatal days were positively associated with volumes of several brain structures in extremely preterm infants at term-equivalent age., Impact: Higher serum levels of DHA in the first 28 postnatal days are positively associated with brain volumes at term-equivalent age in extremely preterm born infants. Especially the most immature infants suffer from low DHA levels in the first 28 postnatal days, with little increase over time. Future research is needed to explore whether postnatal fatty acid supplementation can improve brain development and may serve as a nutritional preventive and therapeutic treatment option in extremely preterm infants., (© 2021. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)
- Published
- 2021
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29. Correction to: Claustrophobia-empowering the patient.
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Björkman-Burtscher IM
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- 2021
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30. Claustrophobia-empowering the patient.
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Björkman-Burtscher IM
- Subjects
- Anxiety, Humans, Patient Compliance, Power, Psychological, Magnetic Resonance Imaging, Phobic Disorders
- Abstract
Key Points: • Claustrophobia, a phobic anxiety disorder, is a well-known relative contraindication for MR, and anxiety or fear is triggered by confinement or the prospect of confinement in the MR environment.• Within the field of MR, claustrophobia is generally counteracted by reducing or deflecting attention from triggering stimuli in the MR environment by technical means, which increases relaxation and comfort and thus improves compliance.• Psychological interventions and self-empowerment of patients might become the next level of coping strategies.
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- 2021
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31. Reporting frequency of radiology findings increases after introducing visual rating scales in the primary care diagnostic work up of subjective and mild cognitive impairment.
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Håkansson C, Torisson G, Londos E, Hansson O, Björkman-Burtscher IM, and van Westen D
- Subjects
- Atrophy, Humans, Magnetic Resonance Imaging, Primary Health Care, Alzheimer Disease, Cognitive Dysfunction diagnostic imaging, Radiology
- Abstract
Objectives: Study the effect of introducing a template for radiological reporting of non-enhanced computed tomography (NECT) in the primary care diagnostic work up of cognitive impairment using visual rating scales (VRS)., Methods: Radiology reports were assessed regarding compliance with a contextual report template and the reporting of the parameters medial temporal lobe atrophy (MTA), white matter changes (WMC), global cortical atrophy (GCA), and width of lateral ventricles (WLV) using established VRS in two age-matched groups examined with NECT before (n = 111) and after (n = 125) the introduction of contextual reporting at our department. True positive rate (TPR) and true negative rate (TNR) before and after were compared., Results: We observed a significant increase in the percentage of radiology reports with mentioning of MTA from 29 to 76% (p < 0.001), WMC from 69 to 86% (p < 0.01), and GCA from 54 to 82% (p < 0.001). We observed a significant increase in the percentages of reports where all of the parameters were mentioned, from 6 to 29% (p < 0.001). There was a significant increase in TPR from 10 to 55% for MTA., Conclusion: This study suggests that contextual radiological assessment using VRS could increase the reporting frequency of radiology findings in the diagnostic work up of cognitive impairment but compliance with templates may be difficult to endorse., Key Points: • Introducing visual rating scales in clinical practice increases the reporting frequency of MTA, WMC, and GCA in the diagnostic work up of subjective and mild cognitive impairment. • Introducing visual rating scales has an effect on the true positive rate of reported MTA. • Compliance with contextual radiology templates remains low when use of the template is not enforced by the department leadership.
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- 2021
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32. 7T MR Safety.
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Fagan AJ, Bitz AK, Björkman-Burtscher IM, Collins CM, Kimbrell V, and Raaijmakers AJE
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- Humans, Magnetic Resonance Spectroscopy, Physics, Magnetic Fields, Magnetic Resonance Imaging adverse effects
- Abstract
Magnetic resonance imaging and spectroscopy (MRI/MRS) at 7T represents an exciting advance in MR technology, with intriguing possibilities to enhance image spatial, spectral, and contrast resolution. To ensure the safe use of this technology while still harnessing its potential, clinical staff and researchers need to be cognizant of some safety concerns arising from the increased magnetic field strength and higher Larmor frequency. The higher static magnetic fields give rise to enhanced transient bioeffects and an increased risk of adverse incidents related to electrically conductive implants. Many technical challenges remain and the continuing rapid pace of development of 7T MRI/MRS is likely to present further challenges to ensuring safety of this technology in the years ahead. The recent regulatory clearance for clinical diagnostic imaging at 7T will likely increase the installed base of 7T systems, particularly in hospital environments with little prior ultrahigh-field MR experience. Informed risk/benefit analyses will be required, particularly where implant manufacturer-published 7T safety guidelines for implants are unavailable. On behalf of the International Society for Magnetic Resonance in Medicine, the aim of this article is to provide a reference document to assist institutions developing local institutional policies and procedures that are specific to the safe operation of 7T MRI/MRS. Details of current 7T technology and the physics underpinning its functionality are reviewed, with the aim of supporting efforts to expand the use of 7T MRI/MRS in both research and clinical environments. Current gaps in knowledge are also identified, where additional research and development are required. Level of Evidence 5 Technical Efficacy 2 J. MAGN. RESON. IMAGING 2021;53:333-346., (© 2020 International Society for Magnetic Resonance in Medicine.)
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- 2021
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33. Randomized Control Trial of Postnatal rhIGF-1/rhIGFBP-3 Replacement in Preterm Infants: Post-hoc Analysis of Its Effect on Brain Injury.
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Horsch S, Parodi A, Hallberg B, Malova M, Björkman-Burtscher IM, Hansen-Pupp I, Marlow N, Beardsall K, Dunger D, van Weissenbruch M, Smith LEH, Hamdani M, Mangili A, Barton N, Ramenghi LA, Hellström A, and Ley D
- Abstract
Background: Postnatal insulin-like growth factor-1 (IGF-1) replacement with recombinant human (rh)IGF-1 and IGF binding protein-3 (rhIGF-1/rhIGFBP-3) is being studied as a potential treatment to reduce comorbidities of prematurity. We have recently reported on a phase II, multicenter, randomized, controlled trial comparing postnatal rhIGF-1/rhIGFBP-3 replacement with standard of care (SOC) in extremely preterm infants (NCT01096784). Maximum severity of retinopathy of prematurity was the primary endpoint of the trial and presence of GMH-IVH/PHI one of the pre-specified secondary endpoints. Infants therefore received serial cranial ultrasound scans (CUS) between birth and term age. In this post-hoc analysis we present a detailed analysis of the CUS data of this trial and evaluate the effect of postnatal rhIGF-1/rhIGFBP-3 replacement on the incidence of different kinds of brain injury in extremely preterm infants. Methods: This report is an exploratory post-hoc analysis of a phase II trial in which infants <28 weeks gestational age were randomly allocated to rhIGF-1/rhIGFBP-3 or SOC. Serial cranial ultrasounds were performed between birth and term-equivalent age. Presence of germinal matrix hemorrhage and intraventricular hemorrhage (GMH-IVH), periventricular hemorrhagic infarction (PHI), post-hemorrhagic ventricular dilatation, and white matter injury (WMI) were scored by two independent masked readers. Results: The analysis included 117 infants; 58 received rhIGF-1/rhIGFBP-3 and 59 received SOC. A trend toward less grade II-III GMH-IVH and PHI was observed in treated infants vs. SOC. A subanalysis of infants without evidence of GMH-IVH at study entry ( n = 104) showed reduced progression to GMH-IVH in treated infants (25.0% [13/52] vs. 40.4% [21/52]; not significant). No effects of rhIGF-1/rhIGFBP-3 on WMI were observed. Conclusion: The potential protective effect of rhIGF-1/rhIGFBP-3 on the occurrence of GMH-IVH/PHI appeared most pronounced in infants with no evidence of GMH-IVH at treatment start., (Copyright © 2020 Horsch, Parodi, Hallberg, Malova, Björkman-Burtscher, Hansen-Pupp, Marlow, Beardsall, Dunger, van Weissenbruch, Smith, Hamdani, Mangili, Barton, Ramenghi, Hellström, Ley and the ROPP-2008-01 Study Team.)
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- 2020
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34. MRI diffusion and perfusion alterations in the mesencephalon and pons as markers of disease and symptom reversibility in idiopathic normal pressure hydrocephalus.
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Agerskov S, Arvidsson J, Ziegelitz D, Lagerstrand K, Starck G, Björkman-Burtscher IM, Wikkelsö C, and Tullberg M
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- Aged, Aged, 80 and over, Case-Control Studies, Cerebrovascular Circulation physiology, Female, Humans, Hydrocephalus, Normal Pressure diagnostic imaging, Hydrocephalus, Normal Pressure surgery, Male, Middle Aged, Pons physiopathology, Postoperative Period, Brain diagnostic imaging, Diffusion Magnetic Resonance Imaging, Hydrocephalus, Normal Pressure pathology, Mesencephalon physiopathology
- Abstract
Introduction: Core symptomatology in idiopathic normal pressure hydrocephalus (iNPH) points at dysfunction in the mesencephalon and pons indicating pathological changes in these regions, but only a few studies have addressed the issue. The aim of this study was to investigate diffusion (ADC) and perfusion patterns pre- and postoperatively in these areas in iNPH., Methods: Twenty iNPH patients and 15 healthy controls were included. Patients underwent a clinical examination and brain MRI pre- and 3-6 months postoperatively. The MRI-scan included diffusion and dynamic susceptibility contrast perfusion weighted sequences. Regions of interest in the mesencephalon and pons were drawn on a FLAIR sequence and co-registered to ADC maps and perfusion data., Results: There were no significant differences in pre or postoperative ADC compared to the control group, however postoperative ADC increased by 10% (p = 0.026) in the mesencephalon and 6% (p = 0.016) in the pons in all patients and also in the subgroup of shunt responders by 11% (p = 0.021) and 4% (p = 0.020), respectively. Preoperative relative cerebral blood flow (rCBF) was similar in iNPH patients and controls. Postoperatively, rCBF increased in shunt responders by 6% (p = 0.02) in the mesencephalon and 11% (p = 0.004) in the pons. This increase correlated with the degree of clinical improvement (rs = 0.80, p = 0.031 and rs = 0.66, p = 0.021, respectively)., Conclusion: The postoperative increase in ADC and the correlation between postoperative increase in rCBF and clinical improvement in the mesencephalon and pons shown in this study point at an involvement of these areas in the core pathophysiology and its reversibility in iNPH., Competing Interests: The authors have declared that no competing interests exist.
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- 2020
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35. Subjectively Reported Effects Experienced in an Actively Shielded 7T MRI: A Large-Scale Study.
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Hansson B, Markenroth Bloch K, Owman T, Nilsson M, Lätt J, Olsrud J, and Björkman-Burtscher IM
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- Healthy Volunteers, Humans, Movement, Prospective Studies, Magnetic Resonance Imaging, Vertigo
- Abstract
Background: Ultrahigh-field (UHF) MRI advances towards clinical use. Patient compliance is generally high, but few large-scale studies have investigated the effects experienced in 7T MRI systems, especially considering peripheral nerve stimulation (PNS) and caregiving., Purpose: To evaluate the quantity, the intensity, and subjective experiences from short-term effects, focusing on the levels of comfort and compliance of subjects., Study Type: Prospective., Population: In all, 954 consecutive MRIs in 801 subjects for 3 years., Field Strength: 7T., Assessment: After the 7T examination, a questionnaire was used to collect data., Statistical Tests: Descriptive statistics, Spearman's rank correlation, Mann-Whitney U-test, and t-test., Results: The majority (63%) of subjects agreed that the MRI experience was comfortable and 93% would be willing to undergo future 7T MRI as a patient (5% undecided) and 82% for research purposes (12% undecided). The most common short-term effects experienced were dizziness (81%), inconsistent movement (68%), PNS (63%), headache (40%), nausea (32%), metallic taste (12%), and light flashes (8%). Of the subjects who reported having PNS (n = 603), 44% experienced PNS as "not uncomfortable at all," 45% as "little or very little uncomfortable," and 11% as "moderate to very much uncomfortable." Scanner room temperature was experienced more comfortable before (78%) than during (58%) examinations, and the noise level was acceptable by 90% of subjects. Anxiety before the examination was reported by 43%. Patients differed from healthy volunteers regarding an experience of headache, metallic taste, dizziness, or anxiety. Room for improvement was pointed out after 117 examinations concerning given information (n = 73), communication and sound system (n = 35), or nursing care (n = 15)., Data Conclusion: Subjectively reported effects occur in actively shielded 7T MRI and include physiological responses and individual psychological issues. Although leaving room for improvement, few subjects experienced these effects being so uncomfortable that they would lead to aversion to future UHF examinations., Level of Evidence: 1 TECHNICAL EFFICACY: Stage 5 J. Magn. Reson. Imaging 2020;52:1265-1276., (© 2020 The Authors. Journal of Magnetic Resonance Imaging published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.)
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- 2020
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36. Tensor-valued diffusion MRI differentiates cortex and white matter in malformations of cortical development associated with epilepsy.
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Lampinen B, Zampeli A, Björkman-Burtscher IM, Szczepankiewicz F, Källén K, Compagno Strandberg M, and Nilsson M
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- Adult, Anisotropy, Axons, Drug Resistant Epilepsy complications, Drug Resistant Epilepsy physiopathology, Drug Resistant Epilepsy surgery, Female, Humans, Male, Malformations of Cortical Development complications, Malformations of Cortical Development physiopathology, Middle Aged, Myelin Sheath, Neurosurgical Procedures, Periventricular Nodular Heterotopia diagnostic imaging, Periventricular Nodular Heterotopia physiopathology, Polymicrogyria diagnostic imaging, Polymicrogyria physiopathology, Young Adult, Cerebral Cortex diagnostic imaging, Diffusion Tensor Imaging, Drug Resistant Epilepsy diagnostic imaging, Gray Matter diagnostic imaging, Malformations of Cortical Development diagnostic imaging, White Matter diagnostic imaging
- Abstract
Objective: Delineation of malformations of cortical development (MCD) is central in presurgical evaluation of drug-resistant epilepsy. Delineation using magnetic resonance imaging (MRI) can be ambiguous, however, because the conventional T
1 - and T2 -weighted contrasts depend strongly on myelin for differentiation of cortical tissue and white matter. Variations in myelin content within both cortex and white matter may cause MCD findings on MRI to change size, become undetectable, or disagree with histopathology. The novel tensor-valued diffusion MRI (dMRI) technique maps microscopic diffusion anisotropy, which is sensitive to axons rather than myelin. This work investigated whether tensor-valued dMRI may improve differentiation of cortex and white matter in the delineation of MCD., Methods: Tensor-valued dMRI was performed on a 7 T MRI scanner in 13 MCD patients (age = 32 ± 13 years) featuring periventricular heterotopia, subcortical heterotopia, focal cortical dysplasia, and polymicrogyria. Data analysis yielded maps of microscopic anisotropy that were compared with T1 -weighted and T2 -fluid-attenuated inversion recovery images and with the fractional anisotropy from diffusion tensor imaging., Results: Maps of microscopic anisotropy revealed large white matter-like regions within MCD that were uniformly cortex-like in the conventional MRI contrasts. These regions were seen particularly in the deep white matter parts of subcortical heterotopias and near the gray-white boundaries of focal cortical dysplasias and polymicrogyrias., Significance: By being sensitive to axons rather than myelin, mapping of microscopic anisotropy may yield a more robust differentiation of cortex and white matter and improve MCD delineation in presurgical evaluation of epilepsy., (© 2020 The Authors. Epilepsia published by Wiley Periodicals LLC on behalf of International League Against Epilepsy.)- Published
- 2020
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37. The clinical significance of the T2-FLAIR mismatch sign in grade II and III gliomas: a population-based study.
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Corell A, Ferreyra Vega S, Hoefling N, Carstam L, Smits A, Olsson Bontell T, Björkman-Burtscher IM, Carén H, and Jakola AS
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- Adult, Brain Neoplasms genetics, Brain Neoplasms pathology, Female, Follow-Up Studies, Glioma genetics, Glioma pathology, Humans, Male, Middle Aged, Neoplasm Grading, Prospective Studies, Retrospective Studies, Sweden epidemiology, Brain Neoplasms epidemiology, Glioma epidemiology, Isocitrate Dehydrogenase genetics, Magnetic Resonance Imaging methods, Mutation
- Abstract
Background: The T2-FLAIR mismatch sign is an imaging finding highly suggestive of isocitrate dehydrogenase mutated (IDH-mut) 1p19q non-codeleted (non-codel) gliomas (astrocytomas). In previous studies, it has shown excellent specificity but limited sensitivity for IDH-mut astrocytomas. Whether the mismatch sign is a marker of a clinically relevant subtype of IDH-mut astrocytomas is unknown., Methods: We included histopathologically verified supratentorial lower-grade gliomas (LGG) WHO grade II-III retrospectively during the period 2010-2016. In the period 2017-2018, patients with suspected LGG radiologically were prospectively included, and in this cohort other diagnoses than glioma could occur. Clinical, radiological and molecular data were collected. For clinical evaluation we included all patients with IDH-mut astrocytomas. In the 2010-2016 cohort DNA methylation analysis with Infinium MethylationEPIC BeadChip (Illumina) was performed for patients with an IDH-mut astrocytoma with available tissue. We aimed to examine the association of the T2-FLAIR mismatch sign with clinical factors and outcomes. Additionally, we evaluated the diagnostic reliability of the mismatch sign and its relation to methylation profiles., Results: Out of 215 patients with LGG, 135 had known IDH-mutation and 1p19q codeletion status. Fifty patients had an IDH-mut astrocytoma and 12 of these (24.0%) showed a mismatch sign. The sensitivity and specificity of the mismatch sign for IDH-mut detection were 26.4 and 97.6%, respectively. There were no differences between patients with an IDH-mut astrocytoma with or without mismatch sign when grouped according to T2-FLAIR mismatch sign with respect to baseline characteristics, clinical outcomes and methylation profiles. The overall interrater agreement between neuroradiologist and clinical neurosurgeons for the T2-FLAIR mismatch sign was significant when all 215 MRI examination assessed (κ = 0.77, p < 0.001, N = 215)., Conclusion: The T2-FLAIR mismatch sign in patients with an IDH-mut astrocytoma is not associated with clinical presentation or outcome. It seems unlikely that the IDH-mut astrocytomas with mismatch sign represent a specific subentity. Finally, we have validated that the T2-FLAIR mismatch sign is a reliable and specific marker of IDH-mut astrocytomas.
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- 2020
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38. Swedish national survey on MR safety compared with CT: a false sense of security?
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Hansson B, Olsrud J, Wilén J, Owman T, Höglund P, and Björkman-Burtscher IM
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- Adult, Aged, Contrast Media, Female, Humans, Male, Medical Errors, Middle Aged, Risk Assessment, Surveys and Questionnaires, Sweden, Young Adult, Allied Health Personnel, Equipment Safety, Magnetic Resonance Imaging statistics & numerical data, Near Miss, Healthcare statistics & numerical data, Occupational Health, Patient Safety, Risk Management, Tomography, X-Ray Computed statistics & numerical data
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Objectives: The objectives were to survey MR safety incidents in Sweden during a 12-month period, to assess severity scores, and to evaluate the confidence of MR personnel in incident-reporting mechanisms., Method: Data were collected within a web-based questionnaire on safety in clinical MR environments with CT for comparison. Data reported MR and CT safety incidents (human injury, material damage, and close calls), incident severity, and confidence of participants in incident-reporting systems., Results: The study population consisted of 529 eligible participants. Participants reported 200 MR and 156 CT safety incidents. Among MR incidents, 16% were given the highest potential severity score. More MR workers (73%) than CT workers (50%) were confident in being aware of any incident occurring at their workplace. However, 69% MR workers (83% for CT) were not aware of reported incidents at their hospitals., Conclusion: Safety incidents resulting in human injury, material damage, and close calls in clinical MR environments do occur. According to national risk assessment recommendations, risk level is high. Results indicated that MR personnel tend to a false sense of security, as a high proportion of staff members were sure that they would have been aware of any incident occurring in their own department, while in reality, incidents did occur without their knowledge. We conclude that false sense of security exists for MR., Key Points: • Safety incidents in clinical MR environments still result in human injury and material damage. • Severity level of MR incidents-assessed using Swedish national risk assessment recommendations-is high. • Confidence of MR personnel in incident-reporting mechanisms is high, but reflects a false sense of security, as a high proportion of staff is unaware of reported incidents in the same workplace.
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- 2020
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39. Microstructural white matter alterations associated to neurocognitive deficits in childhood leukemia survivors treated with cranial radiotherapy - a diffusional kurtosis study.
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Follin C, Svärd D, van Westen D, Björkman-Burtscher IM, Sundgren PC, Fjalldal S, Lätt J, Nilsson M, Johanson A, and Erfurth EM
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- Adult, Antineoplastic Agents adverse effects, Cognitive Dysfunction diagnosis, Cognitive Dysfunction pathology, Diffusion Tensor Imaging, Female, Humans, Male, Memory drug effects, Memory radiation effects, Memory and Learning Tests, Middle Aged, White Matter pathology, White Matter radiation effects, Cancer Survivors, Cognitive Dysfunction etiology, Cranial Irradiation adverse effects, Leukemia therapy, White Matter diagnostic imaging
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Background: Cranial radiotherapy (CRT) is a known risk factor for neurocognitive impairment in survivors of childhood acute lymphoblastic leukemia (ALL). Diffusion tensor imaging (DTI) and diffusional kurtosis imaging (DKI) are MRI techniques that quantify microstructural changes in brain white matter (WM) and DKI is regarded as the more sensitive of them. Our aim was to more thoroughly understand the nature of cognitive deficits after cranial radiotherapy (CRT) in adulthood after childhood ALL. Material and methods: Thirty-eight (21 women) ALL survivors, median age 38 (27-46) years, were investigated at median 34 years after diagnosis. All had been treated with a CRT dose of 24 Gy and with 11 years of complete hormone supplementation. DTI and DKI parameters were determined and neurocognitive tests were performed in ALL survivors and 29 matched controls. Results: ALL survivors scored lower than controls in neurocognitive tests of vocabulary, memory, learning capacity, spatial ability, executive functions, and attention ( p < .001). The survivors had altered DTI parameters in the fornix, uncinate fasciculus, and ventral cingulum (all p < .05) and altered DKI parameters in the fornix, uncinate fasciculus, and dorsal and ventral cingulum ( p < .05). Altered DTI parameters in the fornix were associated with impaired episodic verbal memory ( r = -0.40, p < .04). The left and right uncinate fasciculus ( r = 0.6, p < .001), ( r = -0.5, p < .02) as well as the right ventral cingulum ( r = 0.5, p < .007) were associated with impaired episodic visual memory. Altered DKI parameters in the fornix, right uncinate fasciculus ( r = 0.3, r = 0.05, p = .02), and ventral cingulum ( r = 0.3, p = .02) were associated with impaired results of episodic visual memory. Conclusion: ALL survivors with cognitive deficits demonstrated microstructural damage in several WM tracts that were more extensive with DKI as compared to DTI; this might be a marker of radiation and chemotherapy neurotoxicity underlying cognitive dysfunction.
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- 2019
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40. Improvement in diagnostic quality of structural and angiographic MRI of the brain using motion correction with interleaved, volumetric navigators.
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Andersen M, Björkman-Burtscher IM, Marsman A, Petersen ET, and Boer VO
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- Adult, Female, Humans, Image Enhancement, Male, Middle Aged, Prospective Studies, ROC Curve, Algorithms, Brain diagnostic imaging, Image Processing, Computer-Assisted methods, Magnetic Resonance Angiography methods, Movement, Neuroimaging methods
- Abstract
Introduction: Subject movements lead to severe artifacts in magnetic resonance (MR) brain imaging. In this study we evaluate the diagnostic image quality in T1-weighted, T2-weighted, and time-of-flight angiographic MR sequences when using a flexible, navigator-based prospective motion correction system (iMOCO)., Methods: Five healthy volunteers were scanned during different movement scenarios with and without (+/-) iMOCO activated. An experienced neuroradiologist graded images for image quality criteria (grey-white-matter discrimination, basal ganglia, and small structure and vessel delineation), and general image quality on a four-grade scale., Results: In scans with deliberate motion, there was a significant improvement in the image quality with iMOCO compared to the scans without iMOCO in both general image impression (T1 p<0.01, T2 p<0.01, TOF p = 0.03) and in anatomical grading (T1 p<0.01, T2 p<0.01, TOF p = 0.01). Subjective image quality was considered non-diagnostic in 91% of the scans with motion -iMOCO, but only in 4% of the scans with motion +iMOCO. iMOCO performed best in the T1-weighted sequence and least well in the angiography sequence. iMOCO was not shown to have any negative effect on diagnostic image quality, as no significant difference in diagnostic quality was seen between scans -iMOCO and +iMOCO with no deliberate movement., Conclusion: The evaluation showed that iMOCO enables substantial improvements in image quality in scans affected by subject movement, recovering important diagnostic information in an otherwise unusable scan., Competing Interests: MA is an employee of Philips Danmark A/S.
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- 2019
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41. Short-term effects experienced during examinations in an actively shielded 7 T MR.
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Hansson B, Höglund P, Markenroth Bloch K, Nilsson M, Olsrud J, Wilén J, and Björkman-Burtscher IM
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- Dizziness etiology, Humans, Magnetic Fields, Movement, Patient Compliance, Surveys and Questionnaires, Magnetic Resonance Imaging adverse effects, Radiation Exposure adverse effects
- Abstract
The objective of this study was to evaluate occurrence and strength of short-term effects experienced by study participants in an actively shielded (AS) 7 tesla (7 T) magnetic resonance (MR) scanner, to compare results with earlier reports on passively shielded (PS) 7 T MR scanners, and to outline possible healthcare strategies to improve patient compliance. Study participants (n = 124) completed a web-based questionnaire directly after being examined in an AS 7 T MR (n = 154 examinations). Most frequently experienced short-term effects were dizziness (84%) and inconsistent movement (70%), especially while moving into or out of the magnet. Peripheral nerve stimulation (PNS)-twitching-was experienced in 67% of research examinations and showed a dependence between strength of twitches and recorded predicted PNS values. Of the participants, 74% experienced noise levels as acceptable and the majority experienced body and room temperature as comfortable. Of the study participants, 95% felt well-informed and felt they had had good contact with the staff before the examination. Willingness to undergo a future 7 T examination was high (>90%). Our study concludes short-term effects are often experienced during examinations in an AS 7 T MR, leaving room for improvement in nursing care strategies to increase patient compliance. Bioelectromagnetics. 2019;9999:XX-XX. © 2019 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc., (© 2019 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.)
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- 2019
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42. Detailed assessment of hypothalamic damage in craniopharyngioma patients with obesity.
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Fjalldal S, Follin C, Gabery S, Sundgren PC, Björkman-Burtscher IM, Lätt J, Mannfolk P, Nordström CH, Rylander L, Ekman B, Cheong R, Pålsson A, Petersén Å, and Erfurth EM
- Subjects
- Adolescent, Adult, Cross-Sectional Studies, Female, Humans, Male, Middle Aged, Risk Factors, Young Adult, Craniopharyngioma complications, Craniopharyngioma diagnostic imaging, Craniopharyngioma epidemiology, Craniopharyngioma pathology, Hypothalamus diagnostic imaging, Hypothalamus pathology, Obesity complications, Pituitary Neoplasms complications, Pituitary Neoplasms diagnostic imaging, Pituitary Neoplasms epidemiology, Pituitary Neoplasms pathology
- Abstract
Background/objectives: Hypothalamic obesity (HO) occurs in 50% of patients with the pituitary tumor craniopharyngioma (CP). Attempts have been made to predict the risk of HO based on hypothalamic (HT) damage on magnetic resonance imaging (MRI), but none have included volumetry. We performed qualitative and quantitative volumetric analyses of HT damage. The results were explored in relation to feeding related peptides and body fat., Subjects/methods: A cross-sectional study of childhood onset CPs involving 3 Tesla MRI, was performed at median 22 years after first operation; 41 CPs, median age 35 (range: 17-56), of whom 23 had HT damage, were compared to 32 controls. After exclusions, 35 patients and 31 controls remained in the MRI study. Main outcome measures were the relation of metabolic parameters to HT volume and qualitative analyses of HT damage., Results: Metabolic parameters scored persistently very high in vascular risk particularly among HT damaged patients. Patients had smaller HT volumes compared to controls 769 (35-1168) mm
3 vs. 879 (775-1086) mm3 ; P < 0.001. HT volume correlated negatively with fat mass and leptin among CP patients (rs = -0.67; P < .001; rs = -0.53; P = 0.001), and explained 39% of the variation in fat mass. For every 100 mm3 increase in HT volume fat mass decreased by 2.7 kg (95% CI: 1.5-3.9; P < 0.001). Qualitative assessments revealed HT damage in three out of six patients with normal volumetry, but HT damage according to operation records., Conclusions: A decrease in HT volume was associated with an increase in fat mass and leptin. We present a method with a high inter-rater reliability (0.94) that can be applied by nonradiologists for the assessment of HT damage. The method may be valuable in the risk assessment of diseases involving the HT.- Published
- 2019
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43. Multivoxel 1 H-MR Spectroscopy Biometrics for Preoprerative Differentiation Between Brain Tumors.
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Durmo F, Rydelius A, Cuellar Baena S, Askaner K, Lätt J, Bengzon J, Englund E, Chenevert TL, Björkman-Burtscher IM, and Sundgren PC
- Abstract
We investigated multivoxel proton magnetic resonance spectroscopy (
1 H-MRS) biometrics for preoperative differentiation and prognosis of patients with brain metastases (MET), low-grade glioma (LGG) and high-grade glioma (HGG). In total, 33 patients (HGG, 14; LGG, 9; and 10 MET) were included.1 H-MRS imaging (MRSI) data were assessed and neurochemical profiles for metabolites N-acetyl aspartate (NAA) + NAAG(NAA), Cr + PCr(total creatine, tCr), Glu + Gln(Glx), lactate (Lac), myo-inositol(Ins), GPC + PCho(total choline, tCho), and total lipids, and macromolecule (tMM) signals were estimated. Metabolites were reported as absolute concentrations or ratios to tCho or tCr levels. Voxels of interest in an MRSI matrix were labeled according to tissue. Logistic regression, receiver operating characteristic, and Kaplan-Meier survival analysis was performed. Across HGG, LGG, and MET, average Ins/tCho was shown to be prognostic for overall survival (OS): low values (≤1.29) in affected hemisphere predicting worse OS than high values (>1.29), (log rank < 0.007). Lip/tCho and Ins/tCho combined showed 100% sensitivity and specificity for both HGG/LGG ( P < .001) and LGG/MET ( P < .001) measured in nonenhancing/contrast-enhancing lesional tissue. Combining tCr/tCho in perilesional edema with tCho/tCr and NAA/tCho from ipsilateral normal- appearing tissue yielded 100% sensitivity and 81.8% specificity ( P < .002) for HGG/MET. Best single biomarker: Ins/tCho for HGG/LGG and total lipid/tCho for LGG/MET showed 100% sensitivity and 75% and 100% specificity, respectively. HGG/MET; NAA/tCho showed 75% sensitivity and 84.6% specificity. Multivoxel 1H-MRSI provides prognostic information for OS for HGG/LGG/MET and a multibiometric approach for differentiation may equal or outperform single biometrics., Competing Interests: Conflict of Interest: The authors have no conflict of interest to declare- Published
- 2018
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44. Brain Volumes and Developmental Outcome in Childhood Following Fetal Growth Restriction Leading to Very Preterm Birth.
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Morsing E, Malova M, Kahn A, Lätt J, Björkman-Burtscher IM, Maršál K, and Ley D
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Background: Children born very preterm (PT) after fetal growth restriction (FGR) exhibit cognitive impairment at early school age. The relationship between neurodevelopmental impairment and attained regional brain volumes is unknown. Methods: We studied 23 preterm children with FGR (PT-FGR), 24 matched preterm children AGA (PT-AGA), and 27 matched term AGA children (T-AGA) by measuring brain volumes with magnetic resonance imaging at early school age. Cognitive and motor functions were assessed by the Wechsler Intelligence Scales for Children and the ABC-Movement score. Results: The mean ( SD ) full-scale IQ was 80 (17) in the PT-FGR group and 103 (12) in the PT-AGA group ( p < 0.001). The PT-FGR group had lower mean total, gray matter, white matter, thalamic, cerebellar white matter, and hippocampal volumes as compared to the T-AGA group ( p = 0.01, 0.04, 0.003, 0.002, 0.001, and 0.009, respectively). Brain volumes did not differ significantly between the PT groups. Reduction of hippocampal volume correlated with degree of growth restriction at birth ( r = 0.46, p = 0.05). Neither the full-scale IQ nor the ABC movement score <5th percentile were related to brain volumes. Conclusion: Brain volumes as determined by MRI at early school age were primarily associated with degree of prematurity at birth and less with FGR. Regional brain volumes did not discriminate cognitive and motor function beyond that predicted by gestational age at birth.
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- 2018
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45. Test-specific differences in verbal memory assessments used prior to surgery in temporal lobe epilepsy.
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Ljung H, Strandberg MC, Björkman-Burtscher IM, Psouni E, and Källén K
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- Adult, Aged, Epilepsy, Temporal Lobe surgery, Female, Humans, Male, Middle Aged, Sweden, Young Adult, Epilepsy, Temporal Lobe physiopathology, Mental Recall physiology, Neuropsychological Tests standards, Preoperative Care standards, Retention, Psychology physiology, Verbal Learning physiology
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Objective: To study the relationship between two commonly used verbal memory tests in presurgical evaluation for temporal lobe epilepsy (TLE) in Sweden, the Claeson-Dahl Test for verbal learning and retention (CDT) and the Swedish version of the Rey Auditory Verbal Learning Test (RAVLT)., Methods: Fifty-nine patients with TLE (male: 41%, mean: age 41.7 ± 12.3 years; epilepsy onset at mean age: 18.3 ± 13.1 years) previously tested with the CDT, the RAVLT, and three nonverbal memory tests on the same occasion were included. We performed (1) a principal component analysis (PCA) on test performances in the CDT and the RAVLT as well as in nonverbal memory tests; (2) a Pearson's correlation analysis for memory components, biological age, education, age at epilepsy onset, and self-rating scores for depression and anxiety; and (3) an estimation of clinically significant verbal memory impairment in patients with left TLE and left-sided hippocampal sclerosis., Results: The PCAs showed coherence between the learning variables of the CDT and the RAVLT and divergence between the recall variables of the two tests. The RAVLT delayed recall variable was correlated to four out of five nonverbal memory measures. Both tests showed 70-80% clinically significant impairment of verbal memory in patients with left TLE, with or without hippocampal sclerosis, similar to other cohorts with resistant TLE., Conclusions: The construct structure of the two verbal memory differs. It was shown that the RAVLT correlated with visuospatial memory, whereas the CDT did not. The study highlights that there are important nonoverlapping features regarding verbal recall of the two tests, indicating that these tests cannot fully replace one another., (Copyright © 2018 Elsevier Inc. All rights reserved.)
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- 2018
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46. Impact of donor chest radiography on clinical outcome after lung transplantation.
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Bozovic G, Adlercreutz C, Björkman-Burtscher IM, Reinstrup P, Ingemansson R, Skansebo E, and Geijer M
- Abstract
Background: Organ donation guidelines recommend a "clear" conventional bedside chest radiograph before lung transplantation despite only moderate accuracy for cardiopulmonary abnormalities., Purpose: To evaluate the influence of donor image interpretation on lung transplantation outcome in recipients by following early and late complications, one-year survival, and to correlate imaging findings and blood gas analysis with lung transplantation outcome in recipients., Material and Methods: In 35 lung donors from a single institution clinical reports and study reviews of imaging findings of the mandatory bedside chest radiographs and blood gas analyses were compared with clinical outcome in 38 recipients. Hospitalization time, peri- and postoperative complications, early complications (primary graft dysfunction, infection), 30-day and one-year survival, and forced expiratory volume in 1 s percentage of predicted normal value (FEV1%) at one-year follow-up were analyzed., Results: Findings in clinical reports and study reviews differed substantially, e.g. regarding reported decompensation, edema, infection, and atelectasis. No correlation was shown between imaging findings in clinical report or study review and blood gas analyses in the lung donors compared to postoperative outcome in recipients., Conclusion: The interpretation of the mandatory chest radiograph in its present form does not influence one-year outcome in lung transplantation. Larger imaging studies or a change in clinical routine including computed tomography may provide evidence for future guidelines.
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- 2018
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47. Microstructural white matter alterations and hippocampal volumes are associated with cognitive deficits in craniopharyngioma.
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Fjalldal S, Follin C, Svärd D, Rylander L, Gabery S, Petersén Å, van Westen D, Sundgren PC, Björkman-Burtscher IM, Lätt J, Ekman B, Johanson A, and Erfurth EM
- Subjects
- Adolescent, Adult, Cognitive Dysfunction epidemiology, Cognitive Dysfunction psychology, Craniopharyngioma epidemiology, Craniopharyngioma psychology, Cross-Sectional Studies, Diffusion Tensor Imaging methods, Female, Follow-Up Studies, Humans, Male, Middle Aged, Organ Size, Pituitary Neoplasms epidemiology, Pituitary Neoplasms psychology, Random Allocation, Young Adult, Cognitive Dysfunction diagnostic imaging, Craniopharyngioma diagnostic imaging, Hippocampus diagnostic imaging, Pituitary Neoplasms diagnostic imaging, White Matter diagnostic imaging
- Abstract
Context: Patients with craniopharyngioma (CP) and hypothalamic lesions (HL) have cognitive deficits. Which neural pathways are affected is unknown., Objective: To determine whether there is a relationship between microstructural white matter (WM) alterations detected with diffusion tensor imaging (DTI) and cognition in adults with childhood-onset CP., Design: A cross-sectional study with a median follow-up time of 22 (6-49) years after operation., Setting: The South Medical Region of Sweden (2.5 million inhabitants)., Participants: Included were 41 patients (24 women, ≥17 years) surgically treated for childhood-onset CP between 1958-2010 and 32 controls with similar age and gender distributions. HL was found in 23 patients., Main Outcome Measures: Subjects performed cognitive tests and magnetic resonance imaging, and images were analyzed using DTI of uncinate fasciculus, fornix, cingulum, hippocampus and hypothalamus as well as hippocampal volumetry., Results: Right uncinate fasciculus was significantly altered ( P ≤ 0.01). Microstructural WM alterations in left ventral cingulum were significantly associated with worse performance in visual episodic memory, explaining approximately 50% of the variation. Alterations in dorsal cingulum were associated with worse performance in immediate, delayed recall and recognition, explaining 26-38% of the variation, and with visuospatial ability and executive function, explaining 19-29%. Patients who had smaller hippocampal volume had worse general knowledge ( P = 0.028), and microstructural WM alterations in hippocampus were associated with a decline in general knowledge and episodic visual memory., Conclusions: A structure to function relationship is suggested between microstructural WM alterations in cingulum and in hippocampus with cognitive deficits in CP., (© 2018 The authors.)
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- 2018
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48. Brain Tumor Characterization Using Multibiometric Evaluation of MRI.
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Durmo F, Lätt J, Rydelius A, Engelholm S, Kinhult S, Askaner K, Englund E, Bengzon J, Nilsson M, Björkman-Burtscher IM, Chenevert T, Knutsson L, and Sundgren PC
- Abstract
The aim was to evaluate volume, diffusion, and perfusion metrics for better presurgical differentiation between high-grade gliomas (HGG), low-grade gliomas (LGG), and metastases (MET). For this retrospective study, 43 patients with histologically verified intracranial HGG (n = 18), LGG (n = 10), and MET (n = 15) were chosen. Preoperative magnetic resonance data included pre- and post-gadolinium contrast-enhanced T1-weighted fluid-attenuated inversion recover, cerebral blood flow (CBF), cerebral blood volume (CBV), fractional anisotropy, and apparent diffusion coefficient maps used for quantification of magnetic resonance biometrics by manual delineation of regions of interest. A binary logistic regression model was applied for multiparametric analysis and receiver operating characteristic (ROC) analysis. Statistically significant differences were found for normalized-ADC-tumor (nADC-T), normalized-CBF-tumor (nCBF-T), normalized-CBV-tumor (nCBV-T), and normalized-CBF-edema (nCBF-E) between LGG and HGG, and when these metrics were combined, HGG could be distinguished from LGG with a sensitivity and specificity of 100%. The only metric to distinguish HGG from MET was the normalized-ADC-E with a sensitivity of 68.8% and a specificity of 80%. LGG can be distinguished from MET by combining edema volume (Vol-E), Vol-E/tumor volume (Vol-T), nADC-T, nCBF-T, nCBV-T, and nADC-E with a sensitivity of 93.3% and a specificity of 100%. The present study confirms the usability of a multibiometric approach including volume, perfusion, and diffusion metrics in differentially diagnosing brain tumors in preoperative patients and adds to the growing body of evidence in the clinical field in need of validation and standardization.
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- 2018
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49. Impaired brain metabolism and neurocognitive function in childhood leukemia survivors despite complete hormone supplementation in adulthood.
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Follin C, Erfurth EM, Johansson A, Lätt J, Sundgren PC, Österberg K, Spulber G, Mannfolk P, and Björkman-Burtscher IM
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- Adult, Cognitive Dysfunction etiology, Female, Follow-Up Studies, Gray Matter diagnostic imaging, Gray Matter pathology, Humans, Magnetic Resonance Spectroscopy, Male, Middle Aged, Survivors, Time Factors, White Matter diagnostic imaging, White Matter pathology, Brain diagnostic imaging, Brain metabolism, Brain pathology, Cognitive Dysfunction physiopathology, Cranial Irradiation adverse effects, Hormone Replacement Therapy, Precursor Cell Lymphoblastic Leukemia-Lymphoma drug therapy, Precursor Cell Lymphoblastic Leukemia-Lymphoma radiotherapy
- Abstract
Cranial radiotherapy is a known risk factor for neurocognitive impairment in survivors of childhood acute lymphoblastic leukemia (ALL). Understanding the nature of cognitive dysfunction during adulthood in ALL survivors is important as it has an impact on major life situations. Thirty-eight (21 women) ALL survivors were investigated 34 years after diagnosis. Median-age was 38 (27-46) years. All were treated with a CRT dose of 24Gy and 11 years (3-13) of complete hormone supplementation. Comparisons were made to 29 matched controls. Assessments of magnetic resonance spectroscopy (white and grey matter metabolic alterations), brain volume and neuropsychological tests were performed. ALL survivors demonstrate a generally lower performance in neuropsychological tests. ALL survivors scored lower than controls in vocabulary (p<0.001), memory (p<0.001), learning capacity (p<0.001), spatial ability (p<0.001), executive functions and attention (p<0.001) 34 years after ALL treatment. Compared to controls ALL survivors had reduced white matter (WM) (492 vs 536cm
3 , p<0.001) and grey matter (GM) volumes (525 vs 555cm3 , p=0.001). ALL survivors had lower levels of WM N-acetyl aspartate/creatin (NAA/Cr) (1.48 vs 1.63, p=0.004), WM NAA+NAAG (N-acetylaspartylglutamate)/Cr (1.61 vs 1.85, p<0.001) and lower levels of GM NAA/Cr (1.18 vs 1.30, p=0.001) and GM NAA+NAAG/Cr (1.28 vs 1.34, p=0.01) compared to controls. ALL survivors had higher levels in WM MI (Myoinositol)/NAA (0.65 vs 0.56, p=0.01) concentrations compared to controls. There was a significantly negative correlation of years since ALL diagnosis to WM NAA+NAAG/Cr (r=-0.4, p=0.04) in ALL survivors. The present study shows impaired brain metabolism detected by MRS, reduced brain volumes and neurocognitive impairment in childhood ALL survivors treated with cranial radiotherapy and chemotherapy, despite complete hormone substitution. We also report an impairment of metabolites correlated to time since treatment and a progressive impairment in sustained attention, suggesting an accelerated aging in the irradiated brain. Following these survivors many decades, or throughout life, after treatment with cranial radiotherapy and chemotherapy is highly warranted for a broader understanding of long-term outcome in this patient group., (Copyright © 2016 Elsevier Ltd. All rights reserved.)- Published
- 2016
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50. Circulation stabilizing therapy and pulmonary high-resolution computed tomography in a porcine brain-dead model.
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Bozovic G, Steen S, Sjöberg T, Schaefer-Prokop C, Verschakelen J, Liao Q, Höglund P, Siemund R, and Björkman-Burtscher IM
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- Animals, Blood Gas Analysis, Decapitation, Electrolytes administration & dosage, Electrolytes therapeutic use, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Oxygen blood, Positive-Pressure Respiration, Pulmonary Edema physiopathology, Respiration, Artificial, Sus scrofa, Swine, Tomography, X-Ray Computed, Blood Circulation, Brain Death diagnosis, Lung diagnostic imaging
- Abstract
Background: Currently 80% of donor lungs are not accepted for transplantation, often due to fluid overload. Our aim was to investigate if forced fluid infusion may be replaced by a new pharmacological therapy to stabilize circulation after brain death in an animal model, and to assess therapy effects on lung function and morphology trough blood gas parameters and state-of-the-art High-resolution CT (HRCT)., Methods: Brain death was caused by surgical decapitation. To maintain mean aortic pressure > 60 mmHg, pigs were treated with forced electrolyte solution infusion (GI; n = 6) or the pharmacological therapy (GII; n = 11). GIII (n = 11) were non-decapitated controls. Lung function was investigated with blood gases and lung morphology with HRCT., Results: GI pigs became circulatory instable 4-6 h after brain death in spite of forced fluid infusion, five pigs showed moderate to severe pulmonary edema on HRCT and median final PaO2 /FiO2 was 29 kPa (Q1; Q3; range 26; 40; 17-76). GII and GIII were circulatory stable (mean aortic pressure > 80 mmHg) and median final PaO2 /FiO2 after 24 h was 72 kPa (Q1; Q3; range 64; 76; 53-91) (GII) and 66 kPa (55; 78; 43-90) (GIII). On HRCT, only two pigs in GII had mild pulmonary edema and none in GIII. More than 50% of HRCT exams revealed unexpected lung disease even in spite of PaO2 /FiO2 > 40 kPa., Conclusion: Pharmacological therapy but not forced fluid infusion prevented circulatory collapse and extensive HRCT verified pulmonary edema after acute brain death. HRCT was useful to evaluate lung morphology and revealed substantial occult parenchymal changes justifying efforts toward a more intense use of HRCT in the pre-transplant evaluation., (© 2015 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)
- Published
- 2016
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