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Objectives Traumatic brain injury (TBI) is one of the most common types of brain injuries associated with cognitive impairments. Functional magnetic resonance imaging (fMRI) studies can provide a unique opportunity to examine brain connectivity patterns and understand the neural substrates of cognitive outcomes following traumatic injury. Therefore, this study aims to determine changes in functional connectivity patterns in patients with TBI compared to healthy individuals using two graph models, adaptive dense subgraph discovery (ADSD) and variance component. Materials & Methods This study used fMRI data downloaded from https://openneuro.org. These data included 14 patients with TBI aged between 18 and 36 and 12 healthy individuals (female: N=6, male: N=6) aged between 19 and 52. Out of the 74 regions examined, a cluster of 18 regions related to TBI was identified using the ADSD model. Subsequently, these identified regions were used as input for the variance component model to investigate changes in connectivity patterns. Results Functional connectivity between an 18-brain region cluster, such as the Rectus (Left, Right), Supp_Motor_Area (Left, Right), and Middle Cingulum (Left, Right), differed between the patient and healthy groups. Based on the analysis of functional connectivity between pairs of brain regions, 153 connections between pairs of brain regions were compared in the two groups, out of which 63 connections showed significant differences between the two groups. Compared to other regions, Supp_Motor_Area_Right and Rectus_Left had more connections. Conclusion The study's results indicate that the functional connectivity between the Cingulum, Hippocampus, Fusiform, Supp_Motor_Area, and Precentral regions differs between the two groups. Since these regions are involved in processes such as memory, learning, spatial orientation, face recognition, coordination, and motor control, changes in their functional connectivity may lead to impairments in these areas. [ABSTRACT FROM AUTHOR]

ObjectiveProject 1 of the Preclinical Multicenter Epilepsy Bioinformatics Study for Antiepileptogenic Therapy (EpiBioS4Rx) consortium aims to identify preclinical biomarkers for antiepileptogenic therapies following traumatic brain injury (TBI). The international participating centers in Finland, Australia, and the United States have made a concerted effort to ensure protocol harmonization. Here, we evaluate the success of harmonization process by assessing the timing, coverage, and performance between the study sites.MethodWe collected data on animal housing conditions, lateral fluid-percussion injury model production, postoperative care, mortality, post-TBI physiological monitoring, timing of blood sampling and quality, MR imaging timing and protocols, and duration of video-electroencephalography (EEG) follow-up using common data elements. Learning effect in harmonization was assessed by comparing procedural accuracy between the early and late stages of the project.ResultsThe animal housing conditions were comparable between the study sites but the postoperative care procedures varied. Impact pressure, duration of apnea, righting reflex, and acute mortality differed between the study sites (p  0.05). Plasma quality was poor in 4% of the samples in UEF, 1% in Monash and 14% in UCLA. More than 97% of the final cohort were MR imaged at all timepoints in all study sites. The timing of imaging did not differ on D2 and D9 (p > 0.05), but varied at D30, 5 months, and ex vivo timepoints (p  0.05). A decrease in acute mortality and increase in plasma quality across time reflected a learning effect in the TBI production and blood sampling protocols.SignificanceOur study is the first demonstration of the feasibility of protocol harmonization for performing powered preclinical multi-center trials for biomarker and therapy discovery of post-traumatic epilepsy.

We report the case of a giant lipoma of the quadrigeminal cistern in a 30-year-old female patient with headache, nausea, vomiting, and phono and photophobia. Despite the large size of the tumor, conservative treatment was chosen. Intracranial lipomas are rare benign tumors commonly associated with congenital anomalies, and their origin is related to an incorrect embryonic development. The diagnosis is made mainly by cranial computed tomographyand magnetic resonance imaging. The treatment of lipoma can be surgical or conservative, and there is no single treatment for the different patients' cases.

PurposeTo determine if PSAD, PSADtz, and ADC values improve the accuracy of PI-RADS v2 and identify men whose concurrent systematic biopsy detects clinically significant cancer on areas without mpMRI visible lesions.Materials and methodsSingle reference-center, cross-sectional, retrospective study of consecutive men with suspected or known low to intermediate-risk prostate cancer who underwent 3T mpMRI and TRUS-MRI fusion biopsy from 07/15/2014 to 02/17/2018. Cluster-corrected logistic regression analyses were utilized to predict clinically significant prostate cancer (Gleason score ≥3+4) at targeted mpMRI lesions and on systematic biopsy.Results538 men (median age=66 years, median PSA=7.0ng/mL) with 780mpMRI lesions were included. Clinically significant disease was diagnosed in 371 men. PI-RADS v2 scores of 3, 4, and 5 were clinically significant cancer in 8.0% (16/201), 22.8% (90/395), and 59.2% (109/184). ADC values, PSAD, and PI-RADS v2 scores were independent predictors of clinically significant cancer in targeted lesions (OR 2.25-8.78; P values

Introduction: The objective of this study is to assess the role of diffusion weighted (DW) magnetic resonance imaging (MRI) along with its corresponding apparent diffusion coefficient (ADC) values in differentiating malignant from benign breast lesions. Material and Methods: Patients with breast lesions and those who met inclusion and exclusion criteria were included in this study. MR Mammography (MRM) was performed on 1.5 Tesla MR Scanner (Siemens® Magnetom Avanto®). DWI was performed at b-values of 50, 400 and 800 s/mm² followed by ADC sequence. Results: 50 patients with a total of 81 breast lesions and whose diagnosis was histopathologically confirmed following MRM were included in the study. We observed that benign lesions showed no restricted diffusion with an ADC value of >1.3 x 10-3 mm²/s. Most of the malignant lesions showed restricted diffusion with ADC value of < 1.3 10-3 mm²/s. A non-malignant condition, Benign Phyllodes tumor (n=1) showed no restricted diffusion but had a low ADC of 1.1 x 10-3 giving false positive result. Mucinous carcinomas (n=5) showed no restricted diffusion and had a mean ADC value of >1.3 x 10-3. We observed sensitivity of DWI along with ADC value to be 86.8% and specificity as 97.6%. Conclusion: DW-MRI can be employed as a fast unenhanced screening modality for breast cancer with high sensitivity. Considering ADC values along with DW-MRI increased its detection rates and hence both can be incorporated as supplementary techniques in multiparametric MRM. [ABSTRACT FROM AUTHOR]

Diffusion-weighted imaging (DWI) is considered to be a useful biomarker to characterize the cellularity of lesions, yet its application in the thorax to evaluate anterior mediastinal lesions has not been well investigated. The aims of our study were to describe the magnetic resonance (MR) characteristics of anterior mediastinal masses and to assess the role of apparent diffusion coefficient (ADC) value in distinguishing benign from malignant lesions of the anterior mediastinum. We conducted a retrospective cross-sectional study including 55 patients with anterior mediastinal masses who underwent preinterventional MR scanning with the following sequences: T1 VIBE DIXON pre and post-contrast, T2 HASTE, T2 TIRM, DWI-ADC map (b values of 0 and 2000 sec/mm2). The ADC measurements were obtained by two approaches: hot-spot ROI and whole-tumor histogram analysis. The lesions were grouped by three distinct ways: benign versus malignant, group A (benign lesions and type A, AB, B1 thymoma) versus group B (type B2, B3 thymoma and other malignant lesions), lymphoma versus other malignancies. The study was composed of 55 patients, with 5 benign lesions and 50 malignant lesions. The ADCmean, ADCmedian, ADC10, ADC90 in the histogram-based approach and the hot-spot-ROI-based mean ADC of the malignant lesions were significantly lower than those of benign lesions (P values< 0.05). The hot-spot-ROI-based mean ADC had the highest value in differentiation between benign and malignant mediastinal lesions, as well as between group A and group B; the ADC cutoffs (with sensitivity, specificity) to differentiate malignant from benign lesions and group A from group B were 1.17 x 10-3 mm2/sec (80%, 80%) and 0.99 x 10-3 mm2/sec (78.4%, 88.9%), respectively. The ADC values obtained by using the hot-spot-ROI-based and the histogram-based approaches are helpful in differentiating benign and malignant anterior mediastinal masses. [ABSTRACT FROM AUTHOR]

In this case report, we describe a 60-year-old man who presented with headaches for 1 year and mild confusion for 3 weeks and was initially diagnosed as having a cerebral tumor on the basis of finding a round lesion in the right lenticular nucleus with ring enhancement on gadolinium-enhanced T1-weighted brain magnetic resonance imaging. However, the discovery of positive serology for Treponema pallidum infection on routine tests on admission prompted analysis of cerebrospinal fluid, which was also positive on Treponema pallidum hemagglutination (TPHA), rapid plasma reagin (RPR), and treponemal antibody absorption (FTA-ABS) tests. Thus, he was diagnosed as having an intracranial syphilitic gumma. After commencing treatment with penicillin G, the lesion temporarily increased in size, but subsequently resolved completely with continuing antibiotic treatment. In the present era of increasing prevalence of syphilitic infection and because they are eminently treatable, syphilitic gummas should be included in the differential diagnosis of apparent brain tumors. Additionally, temporary enlargement of a probable gumma after instituting antibiotic treatment should not prompt cessation or change of the antibiotics.

Background: Rectal cancer is one of the most common malignancies of the digestive tract, ranking first in the worldwide incidence of malignant tumors. The early diagnosis, accurate staging and early treatment of rectal cancer are key to improve the five-year survival rate. Rectal MRI plays a crucial role in evaluating rectal cancer by providing multiple prognostic findings and imaging features that guide proper patient management. Aim of the Work: to evaluate the performance of diffusionweighted MRI (DWI) for the detection of lymph nodes and for differentiating between benign and metastatic nodes during primary rectal cancer staging. Patients and Methods: the study was carried out at Ain Shams University Hospitals, Radiodiagnosis Department on 35 patients, 29 patients were histopathologically proven rectal carcinoma underwent surgical resection and 6 cases were potentially free of cancer considered as control. Results: We found that the size of metastatic lymph nodes on DWI was significantly larger than that of non-metastatic lymph nodes (0.976 0.37 vs. 0.46 0.17 cm), most of malignant nodes had rounded shape (55.6 %) vs. oval shaped (70.6%) in benign nodes and almost all of metastatic lymph nodes had irregular margin (97.2%) while all benign nodes appeared having smooth margin. The mean ADC value was significantly lower for metastatic lymph nodes than non-metastatic lymph nodes (1.216 0.54 vs. 1.516 0.51 x 103mm2/sec). In addition, for evaluation of lymph node metastasis that reflects the primary tumor characteristics, the LN/T ratio (defined as the ratio of lymph node ADC value to the primary tumor ADC value) was calculated. It was significantly lower for metastatic lymph nodes than non-metastatic lymph nodes (1.066 0.37 vs. 1.656 0.73). Receiver operating characteristic curve analysis revealed that the best performing cutoffs were 0.5cm for lymph node size, 0.987 x 103mm2/sec for ADC value, and 0.762 for LN/T ratio. Accuracy was significantly greater for lymph nodes with irregular margin (92.3%), than LN/T ratio (78.5%) than for lymph node size (62.0%) or ADC value (74.8%). Conclusion: Preoperative DWI, especially the margin of lymph nodes as well as LN/T ADC ratio, are recommended for evaluation of lymph node metastasis in patient with rectal cancer. [ABSTRACT FROM AUTHOR]

Abstract Background Magnetic resonance imaging (MRI) can show the architecture of the hip joint clearly and has been increasingly used in developmental dysplasia of the hip (DDH) confirmation and follow-up. In this study, MRI was used to observe changes in the hip joints before and after closed reduction (CR) and to explore risk factors of residual acetabular dysplasia (RAD). Methods This is a prospective analysis of unilateral DDH patients with CR and spica cast in our hospital from October 2012 to July 2018. MRI and pelvic plain radiography were performed before and after CR. The labro-chondral complex (LCC) of the hip was divided into four types on MRI images. The variation in the thickening rate of the ligamentum teres, transverse ligaments, and pulvinar during MRI follow-up was analyzed, and the difference in cartilaginous acetabular head index was evaluated. The “complete relocation” rate of the femoral head was analyzed when the cast was changed for the last time, and the necrotic rate of the femoral head was evaluated after 18 months or more after CR. Lastly, the risk factors of RAD were analyzed. Results A total of 63 patients with DDH and CR were included. The LCC was everted before CR and inverted after CR, and the ligamentum teres, transverse ligaments, and pulvinar were hypertrophic before and after CR, and then gradually returned to normal shape. The cartilaginous acetabular head index gradually increased to normal values. Complete relocation was observed in 58.7% of femoral heads, while 8.6% had necrosis. The abnormalities in LCC was related to RAD (OR: 4.35, P = 0.03), and the rate of type 3 LCC in the RAD group was higher. However, the IHDI classification (P = 0.09); the “complete relocation” of femoral heads (P = 0.61); and hypertrophy of the ligamentum teres (P = 1.00), transverse ligaments (P = 1.00), and pulvinar (P = 1.00) were not related to RAD. Conclusions In this study, MRI can observe the variations of the abnormal soft tissue structures of the diseased hips after CR and spica casting, and can evaluate which hips will have RAD after CR. Therefore, we can utilize MRI in DDH patients appropriately.

Abstract Driven by an appreciation of the field’s early stage of development, I apply the concept of exploratory experimentation, originally put forward in the late 90s philosophy of biology, to current research in cognitive neuroscience. I concentrate on functional magnetic resonance imaging and how this wide-spread technique is used, from experimental design to data analysis. I claim that, although subject to certain significant modifications with respect to the concept’s original rendering, the exploratory character of neuroimaging experiments can be appreciated considering their goals, centered on the stabilization of experimental systems for phenomenological description, and the relevance of their methodological facet. Although I do not claim that there is a specific kind of experiment that one can single out as definitely exploratory, exploration can be seen as a general trait imbuing fMRI-based experimentation.

Liver cancer is the sixth most common cancer worldwide and the second leading cause of cancer mortality. Chronic liver disease caused by viral infection, alcohol abuse, or other factors can lead to cirrhosis. Cirrhosis is the most important clinical risk factor for hepatocellular carcinoma (HCC) whereby the normal hepatic architecture is replaced by fibrous septa and a spectrum of nodules ranging from benign regenerative nodules to HCC, each one of them with different imaging features.

Introduction: According to the literature, optical coherence tomography (OCT) can be used measure radiation absorbed dose. This study was carried out to design a computed tomography system for the calculation of absorbed dose and optimization of dose delivery in radiotherapy using gel dosimeters. Material and Methods: An advanced charge-coupled device based OCT system was developed in laboratory with the capability for high resolution three-dimensional (3D) radiation dosimetry using gel dosimeters. The OCT system was compared to magnetic resonance imaging (MRI) as a standard system to investigate its accuracy. Additionally, a number of parameters were checked for assessing the performance of the system. Results: Developing an advanced OCT system, the calibration curve was drawn for OCT and MRI and the received dose values were compared. The amounts of dose obtained from OCT and MRI were 1.98 and 2 Gy respectively with a relative difference of 2%. Conclusion: The quality of treatment can be improved using OCT system in radiotherapy dosimetry.

Background: Magnetic resonance imaging (MRI) can show the architecture of the hip joint clearly and has been increasingly used in developmental dysplasia of the hip (DDH) confirmation and follow-up. In this study, MRI was used to observe changes in the hip joints before and after closed reduction (CR) and to explore risk factors of residual acetabular dysplasia (RAD).Methods: This is a prospective analysis of unilateral DDH patients with CR and spica cast in our hospital from October 2012 to July 2018. MRI and pelvic plain radiography were performed before and after CR. The labro-chondral complex (LCC) of the hip was divided into four types on MRI images. The variation in the thickening rate of the ligamentum teres, transverse ligaments, and pulvinar during MRI follow-up was analyzed, and the difference in cartilaginous acetabular head index was evaluated. The "complete relocation" rate of the femoral head was analyzed when the cast was changed for the last time, and the necrotic rate of the femoral head was evaluated after 18 months or more after CR. Lastly, the risk factors of RAD were analyzed.Results: A total of 63 patients with DDH and CR were included. The LCC was everted before CR and inverted after CR, and the ligamentum teres, transverse ligaments, and pulvinar were hypertrophic before and after CR, and then gradually returned to normal shape. The cartilaginous acetabular head index gradually increased to normal values. Complete relocation was observed in 58.7% of femoral heads, while 8.6% had necrosis. The abnormalities in LCC was related to RAD (OR: 4.35, P = 0.03), and the rate of type 3 LCC in the RAD group was higher. However, the IHDI classification (P = 0.09); the "complete relocation" of femoral heads (P = 0.61); and hypertrophy of the ligamentum teres (P = 1.00), transverse ligaments (P = 1.00), and pulvinar (P = 1.00) were not related to RAD.Conclusions: In this study, MRI can observe the variations of the abnormal soft tissue structures of the diseased hips after CR and spica casting, and can evaluate which hips will have RAD after CR. Therefore, we can utilize MRI in DDH patients appropriately. [ABSTRACT FROM AUTHOR]

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Introduction: Pharmacokinetic (PK) modeling of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is widely applied in tumor diagnosis and treatment evaluation. Precision analysis of the estimated PK parameters is essential when they are used as a measure for therapy evaluation or treatment planning. In this study, the accuracy of PK parameters in brain DCE-MRI studies was quantified in relation to two major sources of error(including pre-contrast longitudinal-relaxation time, T1,0 and flip angle, α). Material and Methods: 3470 dynamic contrast-enhanced-curves were simulated using a wide variation of the PK parameters. The bias of contrast concentration due to the systematic biases in α and T1,0 was calculated and added to both contrast concentration and AIF profiles. Thereafter, the PK parameters were estimated for each simulated curve in the presence of different percentages of relative biases in α and T1,0. The mean percentage error (MPE) of PK parameters was then calculated for all simulated curves. Results: The results indicated that plasma volume(vp) was the most sensitive parameter to bias of contrast concentration, which may overestimate up to 700% in 10% coincidence relative bias in α and T1,0. The lowest MPE was related to the backward transfer constant (kep), which was ~2%-15% in 10% coincidence relative bias in each α and T1, 0. Conclusion: Utilization of a nested model selection technique, along with an accurate estimator, such as maximum-likelihood estimation, created a unique approach for investigating the effect of the bias in the concentration measurement to the estimated PK parameters without the addition of any extra biases to the parameters during the estimation. [ABSTRACT FROM AUTHOR]

Introduction: Detection of small renal masses (SRM) is increasing with the use of cross-sectional imaging, although many incidental lesions have negligible metastatic potential. A method to identify this subtype would aid in risk stratification. A previously reported clear cell likelihood score (ccLS; 1-very unlikely, 2-unlikely, 3-equivocal, 4-likely, and 5-very likely), based on retrospective review of multiparametric magnetic resonance imaging (mpMRI), predicted the likelihood of encountering clear cell renal cell carcinoma (ccRCC) at surgery. Here, we assess the performance of ccLS prospectively assigned for prediction of ccRCC.Methods: Patients with a known renal mass who underwent mpMRI at a single institution between June 2016 and April 2018 were prospectively assigned a ccLS as part of the clinical MRI report. These patients were retrospectively reviewed, and those with a cT1a lesion and available pathological tissue diagnosis (diagnostic biopsy or extirpative surgery) were selected for analysis.Results: In total, 57 patients (mean age 61.7 ± 14.9 years) with 63 cT1a renal masses were identified. Mean tumor size was 2.7 ± 0.7 cm. Defining ccLS 4-5 lesions as positive demonstrated an overall accuracy of 84%, sensitivity of 89%, specificity of 79%, positive predictive value of 84%, and negative predictive value of 86%. A ccLS of 1-2 demonstrates an 86% accuracy and 100% sensitivity/positive predictive value of identifying non-ccRCC histology.Conclusions: Utilizing prospectively assigned ccLS, we confirm that mpMRI can reasonably identify ccRCC histology in cT1a renal masses. Standardization of imaging protocols and reporting criteria such as the ccLS can be used to aid in the diagnosis and management of small renal masses. [ABSTRACT FROM AUTHOR]

Grounded cognition approaches to conceptual representations postulate a close link between conceptual knowledge and the sensorimotor brain systems. The present fMRI study tested, whether a feature-specific representation of concepts, as previously demonstrated for nouns, can also be found for action- and sound-related verbs. Participants were presented with action- and soundrelated verbs along with pseudoverbs while performing a lexical decision task. Sound-related verbs activated auditory areas in the temporal cortex, whereas action-related verbs activated brain regions in the superior frontal gyrus and the cerebellum, albeit only at a more liberal threshold. This differential brain activation during conceptual verb processing partially overlapped with or was adjacent to brain regions activated during the functional localizers probing sound perception or action execution. Activity in brain areas involved in the processing of action information was parametrically modulated by ratings of action relevance. Comparisons of action- and sound-related verbs with pseudoverbs revealed activation for both verb categories in auditory and motor areas. In contrast to proposals of strong grounded cognition approaches, our study did not demonstrate a considerable overlap of activations for action- and sound-related verbs and for the corresponding functional localizer tasks. However, in line with weaker variants of grounded cognition theories, the differential activation pattern for action- and sound-related verbs was near corresponding sensorimotor brain regions depending on conceptual feature relevance. Possibly, action-sound coupling resulted in a mutual activation of the motor and the auditory system for both action- and sound-related verbs, thereby reducing the effect sizes for the differential contrasts. [ABSTRACT FROM AUTHOR]

Background: Recent studies in Caucasians with transient ischaemic attack or ischaemic stroke have demonstrated significant age-specific associations between cerebral small vessel disease (SVD) burden on magnetic resonance imaging and renal impairment. We aimed to validate these findings in a large cohort of Chinese with ischaemic stroke.Methods: In 959 Chinese with ischaemic stroke who received a brain magnetic resonance imaging at the University of Hong Kong, we determined the age-specific associations of renal impairment (glomerular filtration rate < 60 mL/min/1.73 m2) with neuroimaging markers of SVD as well as with the SVD score.Results: Although renal impairment was associated with the SVD score in univariate analysis in all patients (odds ratio 1.61, 95% confidence interval 1.24-2.09, P < .0001), these associations were attenuated after adjusting for age and sex (P = .38). Similar findings were noted in patients with ischaemic stroke due to SVD and non-SVD subtypes. However, in 222 of 959 patients aged <60, renal impairment was independently associated with an increasing microbleed (adjusted odds ratio 6.82, 2.26-20.59), subcortical (4.97, 1.62-15.24) periventricular white matter hyperintensity (3.96, 1.08-14.51) and global SVD burden (3.41, 1.16-10.04; all P < .05) even after adjusting for age, sex, and vascular risk factors. Nevertheless, there were no associations between renal impairment and individual neuroimaging markers of SVD nor with the SVD score in patients aged ≥60 after adjusting for age and sex (all P > .05).Conclusions: In Chinese with ischaemic stroke, renal impairment was independently associated with microbleed, white matter hyperintensity and global SVD burden in individuals aged <60, but not in those aged ≥60, suggesting that there may be shared susceptibilities to premature systemic disease. [ABSTRACT FROM AUTHOR]

Highlights • Seizure occurs in 15% of patients with Wilson disease neurological manifestations. • Cortical and subcortical white matter lesions on MRI predict seizure. • Seizure correlated with serum copper but not with oxidative stress, cytokines, and glutamate. • Seizure is easy to control and refractoriness is rare. Abstract Background There is paucity of studies on predictors of seizures in Wilson disease with neurological manifestation (WDNM), and none has evaluated the role of copper (Cu) induced oxidative stress, proinflammatory and excitotoxicity in the genesis of seizure. Objectives To report frequency, refractoriness, and outcome of seizure in WDNM. We also evaluate role of Cu induced oxidative stress, excitotoxicity and cytokines in predicting seizures. Methods The diagnosis of WDNM was based on clinical, MRI, KF ring and 24 h urinary Cu. Detailed clinical examination including severity of WD, occurrence of seizure, seizure semiology, antiepileptic drug (AED) and breakthrough seizures were noted. Cranial MRI and electroencephalography findings were noted. Serum free-Cu, oxidative stress markers (glutathione, total antioxidant capacity, malondialdehyde), glutamate and cytokines (interleukin 6, 8 and 10 and tumour necrosis factor α) were measured by atomic absorption spectrophotometer, spectrophotometer, fluorometer and flow cytometer respectively, and correlated with seizures. Patients were treated with zinc with or without penicillamine, and those with epilepsy received second-generation antiepileptic drugs (AEDs). Results Out of 110 patients with WDNM, 16(14.5%) had seizures; focal in 11(68.7%) and generalized in 5(31.3%). Patients with seizure had higher serum free-Cu (35.87 ± 1.34 vs 31.72 ± 0.68; P = 0.02), severe dystonia (P = 0.04), and more frequent cortical (100% vs 6.4%; P < 0.01) and subcortical (81.3% vs 20.2%; P < 0.01) lesions on MRI compared to those without seizure. Oxidative stress markers (glutathione, total antioxidant capacity, malondialdehyde), cytokines and glutamate were elevated in WDNM compared to controls. On multivariate logistic regression analysis, cortical involvement (OR = 105.49; 95%CI = 8.74–1272.39; P < 0.01) and number of MRI lesions (OR = 1.99; 95% CI = 1.11–3.57; P = 0.02) were independent predictors of seizure. The seizures were controlled with single and dual AEDs in seven patients each, and two patients needed three AEDs. All the patients had seizure remission for a median follow up of 66(24–180) months. Conclusion About one-sixth WDNM patients have seizures especially in those with cortical and extensive MRI lesions. Seizures are easily controlled by AEDs. [ABSTRACT FROM AUTHOR]

Introduction: According to the literature, optical coherence tomography (OCT) can be used measure radiation absorbed dose. This study was carried out to design a computed tomography system for the calculation of absorbed dose and optimization of dose delivery in radiotherapy using gel dosimeters. Material and Methods: An advanced charge-coupled device based OCT system was developed in laboratory with the capability for high resolution three-dimensional (3D) radiation dosimetry using gel dosimeters. The OCT system was compared to magnetic resonance imaging (MRI) as a standard system to investigate its accuracy. Additionally, a number of parameters were checked for assessing the performance of the system. Results: Developing an advanced OCT system, the calibration curve was drawn for OCT and MRI and the received dose values were compared. The amounts of dose obtained from OCT and MRI were 1.98 and 2 Gy respectively with a relative difference of 2%. Conclusion: The quality of treatment can be improved using OCT system in radiotherapy dosimetry. [ABSTRACT FROM AUTHOR]

Purpose: Mammography is the most commonly used diagnostic test for breast lesion detection and evaluation, but in dense breast parenchyma it lowers its sensitivity to detect small lesions. Sensitivity and specificity improves with combined use of contrast-enhanced magnetic resonance imaging (CE-MRI) and diffusion-weighted imaging (DWI) in differentiating benign and malignant breast lesions. The aim of the study was to evaluate the effectivity of combined dynamic CE-MRI and DWI in differentiating benign and malignant lesions, and to calculate the apparent diffusion coefficient (ADC) values of malignant and benign lesions of the breast. Material and methods: Fifty-seven patients with 68 lesions were included in the study. MRI of breast using different sequences was acquired on 1.5 Tesla Machine with dedicated breast coils. Dynamic CE-MRI along with DWI was acquired for each patient. Histopathological reports were accepted as the standard of reference. Results: Out of 68 lesions, 37 were malignant on biopsy (54.4%) and 31 were benign (45.5%). The sensitivity of CE-MRI was 92%, specificity 84.21%, positive predictive values (PPV) 88.46 %, and negative predictive values (NPP) 88.89%. The sensitivity of DWI-MRI was 91.6%, specificity was 90.6%, PPV 91.6%, and NPP 90.6%. The sensitivity of combined DWI-MRI and CE-MRI was 95.0%, specificity was 96.43%, PPV 97.44%, and NPP 93.10%. Mean ADCs of benign lesions (b = 800) was 1.905 ± 0.59 × 10-3 mm (2)/s, which was significantly higher than those of malignant lesions (b = 800) 1.014 ± 0.47 × 10-3 mm (2)/s. Conclusion: Multi-parametric MRI is an excellent non-invasive modality with high sensitivity and specificity to differentiate malignant from benign breast lesions. [ABSTRACT FROM AUTHOR]

Objective: Besides cardiac sarcoidosis, FDG-PET is rarely used in the diagnosis of myocardial inflammation, while cardiac MRI (CMR) is the actual imaging reference for the workup of myocarditis. Using integrated PET/MRI in patients with suspected myocarditis, we prospectively compared FDG-PET to CMR and the feasibility of integrated FDG-PET/MRI in myocarditis.Methods: A total of 65 consecutive patients with suspected myocarditis were prospectively assessed using integrated cardiac FDG-PET/MRI. Studies comprised T2-weighted imaging, late gadolinium enhancement (LGE), and simultaneous PET acquisition. Physiological glucose uptake in the myocardium was suppressed using dietary preparation.Results: FDG-PET/MRI was successful in 55 of 65 enrolled patients: two patients were excluded due to claustrophobia and eight patients due to failed inhibition of myocardial glucose uptake. Compared with CMR (LGE and/or T2), sensitivity and specificity of PET was 74% and 97%. Overall spatial agreement between PET and CMR was κ = 0.73. Spatial agreement between PET and T2 (κ = 0.75) was higher than agreement between PET and LGE (κ = 0.64) as well as between LGE and T2 (κ = 0.56).Conclusion: In patients with suspected myocarditis, FDG-PET is in good agreement with CMR findings. [ABSTRACT FROM AUTHOR]

Objective To summarize the MR I characteristics of rosette-forming glioneuronal tumor of the fourth ventricle (RGNT). Methods The clinical, MRI and pathological data of 13 patients with RGNT were retrospectively analyzed. Results The lesions were located in the fourth ventricle (7) with 1 also involving the culmen of cerebellum and fourth ventricle or in the cerebellar hemispheres and vermis (6). The tumors were mixed solid-cystic (6) or solid (4) masses with heterogeneous signal intensities in the solid part, 6 of which showed punctiform or patchy short T1 and T2 signals. The solid components of the tumors showed punetiform, patchy and botrvoid enhancement. The 3 remaining cystic masses had heterogeneously enhanced partially thin or thick cystic; walls. Of 7 patients with CT examinations, 4 showed hyperdense cystic wall or solid part corresponding to angiogenesis on pathology. Conclusion RGNT should be considered in mixed solid-cystic or solid masses with heterogeneous signal intensities and contrast enhancement involving the cerebellum or forth ventricle. [ABSTRACT FROM AUTHOR]

Background: Studies of the epidemiology and outcomes of avascular necrosis (AVN) require accurate case-finding methods. The aim of this study was to evaluate performance characteristics of a claims-based algorithm designed to identify AVN cases in administrative data.Methods: Using a centralized patient registry from a US academic medical center, we identified all adults aged ≥18 years who underwent magnetic resonance imaging (MRI) of an upper/lower extremity joint during the 1.5 year study period. A radiologist report confirming AVN on MRI served as the gold standard. We examined the sensitivity, specificity, positive predictive value (PPV) and positive likelihood ratio (LR+) of four algorithms (A-D) using International Classification of Diseases, 9th edition (ICD-9) codes for AVN. The algorithms ranged from least stringent (Algorithm A, requiring ≥1 ICD-9 code for AVN [733.4X]) to most stringent (Algorithm D, requiring ≥3 ICD-9 codes, each at least 30 days apart).Results: Among 8200 patients who underwent MRI, 83 (1.0% [95% CI 0.78-1.22]) had AVN by gold standard. Algorithm A yielded the highest sensitivity (81.9%, 95% CI 72.0-89.5), with PPV of 66.0% (95% CI 56.0-75.1). The PPV of algorithm D increased to 82.2% (95% CI 67.9-92.0), although sensitivity decreased to 44.6% (95% CI 33.7-55.9). All four algorithms had specificities >99%.Conclusion: An algorithm that uses a single billing code to screen for AVN among those who had MRI has the highest sensitivity and is best suited for studies in which further medical record review confirming AVN is feasible. Algorithms using multiple billing codes are recommended for use in administrative databases when further AVN validation is not feasible. [ABSTRACT FROM AUTHOR]

FUNDAMENTO: A ressonância magnética é um método eficaz para estudo da cardiomiopatia hipertrófica. OBJETIVO: Avaliar, pela ressonância magnética, os parâmetros de função sistólica, perfusão e viabilidade miocárdica em pacientes portadores de cardiomiopatia hipertrófica, comparando os grupos com e sem obstrução na via de saída do ventrículo esquerdo. MÉTODO: Vinte e um pacientes com diagnóstico de cardiomiopatia hipertrófica realizaram estudos de função, viabilidade e perfusão miocárdica nas fases de estresse e de repouso pela ressonância magnética. RESULTADOS: Os segmentos ventriculares mais comprometidos pela hipertrofia foram os da região septal. O grupo obstrutivo apresentou distribuição segmentar de espessura miocárdica semelhante ao não-obstrutivo, porém com maiores médias que o primeiro grupo. A média da fração de ejeção dos pacientes do grupo obstrutivo foi maior que o grupo não-obstrutivo, enquanto as médias dos volumes sistólico e diastólico finais foram menores no grupo obstrutivo. Houve correlação positiva entre a espessura segmentar do ventrículo e a massa segmentar do realce tardio. A indução de estresse determinou aumento do número de segmentos com alteração de perfusão e essa alteração foi mais evidente no grupo obstrutivo. CONCLUSÃO: Os segmentos ventriculares com maior espessura são os septais. As regiões hipertróficas estão associadas à maior extensão de realce tardio. Houve correlação positiva entre as áreas de hipertrofia ventricular e perfusão miocárdica alterada, e esses achados foram mais evidentes no grupo obstrutivo.FUNDAMENTO: La resonancia magnética es un método eficaz para estudio de la cardiomiopatía hipertrófica. OBJETIVO: Evaluar, por la resonancia magnética, los parámetros de función sistólica, perfusión y viabilidad miocárdica en pacientes portadores de cardiomiopatía hipertrófica, comparando los grupos con y sin obstrucción en la vía de salida del ventrículo izquierdo. MÉTODO: Veinte y un pacientes con diagnóstico de cardiomiopatía hipertrófica realizaron estudios de función, viabilidad y perfusión miocárdica en las fases de estrés y de reposo por la resonancia magnética. RESULTADOS: Los segmentos ventriculares más comprometidos por la hipertrofia fueron los de la región septal. El grupo obstructivo presentó distribución segmental de espesor miocárdico semejante al no obstructivo, pero con mayores promedios que el primer grupo. El promedio de la fracción de eyección de los pacientes del grupo obstructivo fue mayor que el grupo no obstructivo, mientras que los promedios de los volúmenes sistólico y diastólico finales se hallaron menores en el grupo obstructivo. Hubo correlación positiva entre el espesor de los segmentos del ventrículo y la masa segmental del realce tardío. La inducción de estrés determinó aumento del número de segmentos con alteración de perfusión, y esa alteración fue más evidente en el grupo obstructivo. CONCLUSIÓN: Los segmentos ventriculares con mayor espesor son los septales. Las regiones hipertróficas están asociadas a la mayor extensión de realce tardío. Hubo correlación positiva entre las áreas de hipertrofia ventricular y perfusión miocárdica alterada, y estos hallazgos fueron más evidentes en el grupo obstructivo.BACKGROUND: The magnetic resonance imaging (MRI) is an effective method to study hypertrophic cardiomyopathy (HCM). OBJECTIVE: To evaluate, using MRI, the parameters of systolic function, perfusion and myocardial viability in patients with HCM, comparing the groups with and without obstruction of the left ventricular outflow tract. METHODS: Twenty-one patients with a diagnosis of HCM underwent the assessment of myocardial function, viability and perfusion under stress and at rest through MRI. RESULTS: The ventricular segments most severely impaired by hypertrophy were those of the septal region. The obstructive group presented segmental myocardial thickening distribution similar to the non-obstructive group, but with higher means than the first group. The mean ejection fraction of the patients in the obstructive group was higher than in the non-obstructive group, whereas the means of the end systolic and diastolic volumes were lower in the obstructive group. There was a positive correlation between the ventricular segmental thickening and the late enhancement segmental mass. The stress induction resulted in an increase in the number of segments with perfusion alterations and this alteration was more evident in the obstructive group. CONCLUSION: The thickest ventricular segments are the septal ones. The hypertrophic regions are associated to a greater extension of late enhancement. There was a positive correlation between the areas of ventricular hypertrophy and altered myocardial perfusion and these findings were more evident in the obstructive group.

Hypereosinophilia may be due to several aetiologies. Cardiac complications are not uncommon, whatever the causes. Clinical presentations of hypereosinophilic cardiac diseases may vary widely from asymptomatic form to fatal necrotic myocarditis or irreversible restrictive cardiomyopathy. As a major cause of morbidity and mortality, diagnosis of cardiac involvement is crucial. Until recently the diagnosis was exclusively based on cardiac biopsy. Nowadays, multimodal cardiac imaging, including echocardiography and cardiac magnetic resonance imaging, is the cornerstone of the diagnosis. Cardiac magnetic resonance imaging has emerged as a very useful tool for the diagnosis allowing precise tissue characterization. It has even been proposed as a surrogate to cardiac biopsy. It should be systematically performed in case of hypereosinophilia. Early and appropriate treatment is crucial to avoid the evolution toward irreversible cardiac lesions. These treatments are symptomatic but should also be adapted to the underlying diseases. [ABSTRACT FROM AUTHOR]

Background: To assess multimodal imaging features of medication-related osteonecrosis of the jaw (MRONJ) and to analyze the differences between oral and parenteral routes of medication administration. We retrospectively reviewed panoramic radiographs, CT, MRI, and bone scintigraphy of patients with MRONJ. Material/Methods: A retrospective study was conducted in 16 patients with MRONJ who underwent panoramic radiography, CT, MRI, and bone scintigraphy. Statistical analysis for the comparison between routes of medication administration and multimodal imaging features was performed with the Pearson's c2 test. Results: The percentage of cases with sequestrum separation was 25.0% (4/16 cases) on panoramic radiography and 81.3% (13/16 cases) on CT. The percentage of cases with periosteal bone proliferation on CT was 41.7% (5/12 cases) in the oral route of administration vs. 100% (4/4 cases) in the parenteral route of administration (p=0.042). The percentage of cases with spread of soft tissue inflammation to buccal and other spaces on CT and MRI was 33.3% (4/12 cases) in the oral route of administration vs. 100% (4/4 cases) in the parenteral route of administration (p=0.021). Conclusions: The sequestrum separation on panoramic radiography in patients with MRONJ was unclear in comparison to CT. Furthermore, characteristic CT findings of patients with MRONJ in the parenteral administration group were periosteal bone proliferation and spread of soft tissue inflammation to buccal and other spaces. [ABSTRACT FROM AUTHOR]

Computational tools for full-wave three-dimensional (3-D) simulations of linear passive electromagnetic (EM) components have reached a point where they became both practical and necessary in computer aided design (CAD) of RF devices. Although circuit-based solvers still offer unprecedented speed and true real-time tuning, full-wave software tools, which take into account almost all physical EM phenomena, rapidly approach similar efficiency and applicability. This, however, is not possible by just using modern hardware environment, but it also requires the numerical method of choice, encapsulated within a software tool, to be extremely precise and conservative in consumption of computer resources, i.e., CPU and memory. We here report a case study which demonstrates highly efficient utilization of higher order large-domain method of moments (MoM) modeling and optimization using WIPL-D. The example includes an RF exciter, based on axial-mode helical antennas mounted on a dielectric support, designed for utilization in the state-of-the-art pre-clinical magnetic resonance imaging (MRI) scanners. [ABSTRACT FROM AUTHOR]

Neutron imaging has been recognized to be very useful to investigate inside of materials and products that cannot be seen by X-ray. New imaging methods using the pulsed structure of neutron sources based on accelerators has been developed also at compact accelerator-driven neutron sources and opened new application fields in neutron imaging. The world’s first dedicated imaging instrument at pulsed neutron sources was constructed at J-PARC in Japan owing to the development of such new methods. Then, usefulness of the compact accelerator-driven neutron sources in neutron science was recognized and such facilities were newly constructed in Japan. Now, existing and new sources have been used for neutron imaging. Traditional imaging and newly developed pulsed neutron imaging such as Bragg edge transmission have been applied to various fields by using compact and large neutron facilities. Here, compact accelerator-driven neutron sources used for imaging in Japan are introduced and some of their activities are presented.

To assess the pattern of right ventricular (RV) functional recovery in a cohort of patients with successful reperfusion of a first episode of acute myocardial infarction (AMI) with 2D speckle-tracking echocardiography and cardiac magnetic resonance imaging (CMR). Ninety-five revascularized AMI patients were prospectively included (56.8 ± 11.1 years, 48 inferior, 47 anterior). RV function was assessed by echocardiography and CMR within the initial 72 h and 6 months later. A RV global strain was calculated while averaging strain values from septal, lateral and inferior walls. At the acute phase, RVEF was lower in inferior than in anterior AMI patients (52.5 ± 6.8 vs. 56.0 ± 4.8, p = 0.006). Similarly, RV global, inferior and lateral strains were lower in inferior MI patients ( p < 0.001 for all) whereas septal strain was not significantly different across groups. At 6 months, RVEF and all strain parameters improved compared to baseline. Improvements were more substantial for patients with inferior than with anterior MI. RV parameters ultimately reached similar levels in the two groups at 6 months except for inferior strain which remained lower in patients with inferior MI (−24.5 ± 6.5 vs. −27.5 ± 5.4, p = 0.03). In low risk patients after AMI, RV function ultimately recovered over the 6 months of follow up. Higher levels of both initial impairment and subsequent recovery were observed for inferior MI. Although RV function was relatively preserved in these patients, RV strain analysis revealed a persistent impairment of RV inferior strain in patients with inferior MI, which may not be identified by RVEF or conventional echocardiographic parameters. [ABSTRACT FROM AUTHOR]

To realize neutron energy resolved three-dimensional (3D) imaging in the resonance neutron energy region, a camera system coupled with a high sensitivity and high frame-rate gating image-intensifier was developed. The resonance absorption 3D imaging was successfully demonstrated at the pulsed neutron source of the Japan Proton Accelerator Research Complex (J-PARC). The camera system allowed us to obtain a time-of-flight (TOF) image of 2352 (W)×1726 (H) pixels resolved into a narrow energy range. 3D images with enhanced contrast at corresponding resonance energy regions for cylindrical Au, Ta, and In samples were reconstructed by convolution filtered back-projection (FBP) and maximum likelihood expectation maximization (MLEM) methods. The spatial resolution in the depth direction was evaluated experimentally to be approximately 1 mm. Our results show that the system could have applications in industrial fields. [ABSTRACT FROM AUTHOR]

Introduction REM sleep behavior disorder (RBD) is a common non motor feature of Parkinson's Disease (PD) affecting about half the patients with this disease. Distinct structural brain tissue abnormalities have been reported in several regions modulating REM sleep of the patients with idiopathic RBD. At the present time, there are no conventional MRI studies investigating patients with PD associated with RBD. Methods Herein, we used voxel-based morphometry (VBM) to detect the neuroanatomical profile of PD patients with and without RBD. Optimized VBM was applied to the MRI brain images in 11 PD patients with RBD (PD-RBD), 11 PD patients without RBD (PD) and 18 age-and sex-matched controls. To corroborate VBM findings we used automated volumetric method (FreeSurfer) to quantify subcortical brain regions volumes. Patients and controls also underwent DAT-SPECT and cardiac MIBG scintigraphies. Results The VBM analysis showed markedly reduced gray matter volume in the right thalamus of PD-RBD patients in comparison with PD patients and controls. Automatic thalamic segmentation in PD-RBD patients showed a bilaterally reduced thalamic volume as compared with PD patients or controls. All PD patients (with and without RBD) showed a reduced tracer uptake on DAT-SPECT and cardiac MIBG scintigraphies as compared to controls. Conclusions Our findings suggest that the presence of RBD symptoms in PD patients is associated with a reduced thalamic volume suggesting a pathophysiologic role of the thalamus in the complex circuit causing RBD. [ABSTRACT FROM AUTHOR]

Marchiafava-Bignami disease is a rare affliction characterized by primary degeneration of the corpus callosum associated with chronic consumption of ethanol. The disease may occasionally occur in patients who are not alcoholics but are chronically malnourished. A complex deficiency of group B vitamins is the main etiopathogenic hypothesis, and many patients improve after the administration of these compounds. However, a good response is not always observed. The definitive diagnosis of Marchiafava-Bignami disease can be problematic and is based on features of neuroimaging studies, especially magnetic resonance imaging. Its treatment is still controversial and shows variable results. Because nutritional factors are implicated, as in Wernicke's encephalopathy, some authors claim that replacement of B vitamins is beneficial. The present article is a case report of a severe acute form of Marchiafava-Bignami disease in an alcohol-dependent male patient who improved after the administration of parenteral B vitamins. As a consequence of his neurological and immunologic conditions, he developed multiple pulmonary infections and had a protracted course in the intensive care unit. He eventually died of sepsis associated with an uncommon fungus, Rhodotorula mucilaginosa. The present article reports the clinical and neuroimaging data from this patient and contains a review of Marchiafava- Bignami disease and Rhodotorula infections in the intensive care unit. [ABSTRACT FROM AUTHOR]

The purpose of this case report was to report a rare case of pyogenic spondylodiscitis caused by Campylobacter fetus . A 37-year-old male presented with fever and low back pain. By lumbar magnetic resonance imaging (MRI), no abnormal finding was observed at the first presentation. However, low back pain was aggravated, and fever did not improve. Thus, lumbar MRI was repeated on the 26 day after the onset of symptoms, showing abnormal signals at vertebrae and disc spaces, and pyogenic spondylitis was diagnosed. The possibility of pyogenic spondylodiscitis should be taken into account if a patient presents with low back pain and fever, and areas of low signal intensity on a T1-weighted MRI should be carefully examined. When initial MRI does not reveal abnormal findings, repeated MRI after one or two weeks or, more favorably, immediate gadolinium enhancement MRI, are important for patients who have persistent low back pain and fever. [ABSTRACT FROM AUTHOR]