50 results on '"Krisa L"'
Search Results
2. Microstructural alterations of major thalamic nuclei in the chronic pediatric spinal cord injured population
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Kang, K., primary, Fleming, K., additional, Sathe, A., additional, Muller, J., additional, Harrop, J., additional, Middleton, D., additional, Heller, J.E., additional, Sharan, A., additional, Mohamed, F., additional, Krisa, L., additional, and Alizadeh, M., additional
- Published
- 2023
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3. Microstructural Alterations of Major Thalamic Nuclei in the Chronic Pediatric Spinal Cord Injured Population
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Kang, K., Fleming, K., Sathe, A., Muller, J., Harrop, J., Middleton, D., Heller, J., Sharan, A., Mohamed, F., Krisa, L., Alizadeh, M., Kang, K., Fleming, K., Sathe, A., Muller, J., Harrop, J., Middleton, D., Heller, J., Sharan, A., Mohamed, F., Krisa, L., and Alizadeh, M.
- Abstract
BACKGROUND: The brain undergoes reorganization following spinal cord injury (SCI), but little is known about how the thalamus is affected in pediatric SCIs. PURPOSE: To characterize microstructural alterations in the thalamus after SCI with diffusion tensor imaging (DTI) metrics. METHODS: 18 pediatric participants with chronic SCI (8-20 years) were stratified using the American Spinal Injury Association Impairment Scale (AIS) into groups: A, B, and C/D. DTI of the brain used a 3 T Siemens Verio MRI using the parameters: 20 directions, number of averages = 3, b = 1000 s/mm DATA ANALYSIS: DTI metrics were acquired by superimposing the AAL3 thalamic atlas onto participant diffusion images registered to MNI152 space. We utilized a multiple Mann-Whitney U-test to compare between AIS groups, considering values of p ≤ 0.05 as significant. RESULTS: FA, AD, RD, and MD significantly differed in thalamic nuclei between AIS groups A vs B and B vs C/D. Significant nuclei include the right ventral anterior, left intralaminar, bilateral lateral pulvinar, and right lateral geniculate. CONCLUSION: Our findings suggest the presence of microstructural alterations based on SCI severity in pediatric patients. These results are encouraging and warrant further study.
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- 2023
4. Atlas-Based Quantification of DTI Measures in a Typically Developing Pediatric Spinal Cord
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Shahrampour, S., primary, De Leener, B., additional, Alizadeh, M., additional, Middleton, D., additional, Krisa, L., additional, Flanders, A.E., additional, Faro, S.H., additional, Cohen-Adad, J., additional, and Mohamed, F.B., additional
- Published
- 2021
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5. Atlas-based quantification of DTI measures in a typically developing pediatric spinal cord
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Shahrampour, S., De Leener, Benjamin, Alizadeh, M., Middleton, D., Krisa, L., Flanders, A.E., Faro, S.H., Cohen-Adad, Julien, Mohamed, F.B., Shahrampour, S., De Leener, Benjamin, Alizadeh, M., Middleton, D., Krisa, L., Flanders, A.E., Faro, S.H., Cohen-Adad, Julien, and Mohamed, F.B.
- Abstract
BACKGROUND AND PURPOSE: Multi-parametric MRI, provides a variety of biomarkers sensitive to white matter integrity, However, spinal cord MRI data in pediatrics is rare compared to adults. The purpose of this work was 3-fold: 1) to develop a processing pipeline for atlasbased generation of the typically developing pediatric spinal cord WM tracts, 2) to derive atlas-based normative values of the DTI indices for various WM pathways, and 3) to investigate age-related changes in the obtained normative DTI indices along the extracted tracts. MATERIALS AND METHODS: DTI scans of 30 typically developing subjects (age range, 6–16 years) were acquired on a 3T MR imaging scanner. The data were registered to the PAM50 template in the Spinal Cord Toolbox. Next, the DTI indices for various WM regions were extracted at a single section centered at the C3 vertebral body in all the 30 subjects. Finally, an ANOVA test was performed to examine the effects of the following: 1) laterality, 2) functionality, and 3) age, with DTI-derived indices in 34 extracted WM regions. RESULTS: A postprocessing pipeline was developed and validated to delineate pediatric spinal cord WM tracts. The results of ANOVA on fractional anisotropy values showed no effect for laterality (P ¼ .72) but an effect for functionality (P , .001) when comparing the 30 primary WM labels. There was a significant (P , .05) effect of age and maturity of the left spinothalamic tract on mean diffusivity, radial diffusivity, and axial diffusivity values. CONCLUSIONS: The proposed automated pipeline in this study incorporates unique postprocessing steps followed by template registration and quantification of DTI metrics using atlas-based regions. This method eliminates the need for manual ROI analysis of WM tracts and, therefore, increases the accuracy and speed of the measurements.
- Published
- 2021
6. Validation of the National Institute of Neurological Disorders and Stroke Spinal Cord Injury MRI Common Data Elements Instrument
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Fisher, J., primary, Krisa, L., additional, Middleton, D.M., additional, Leiby, B.E., additional, Harrop, J.S., additional, Shah, L.M., additional, Schwartz, E.D., additional, Doshi, A., additional, Faro, S.H., additional, Mohamed, F.B., additional, and Flanders, A.E., additional
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- 2021
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7. Diffusion Tensor Imaging of the Normal Cervical and Thoracic Pediatric Spinal Cord
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Saksena, S., primary, Middleton, D.M., additional, Krisa, L., additional, Shah, P., additional, Faro, S.H., additional, Sinko, R., additional, Gaughan, J., additional, Finsterbusch, J., additional, Mulcahey, M.J., additional, and Mohamed, F.B., additional
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- 2016
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8. Evaluation of the Elder Abuse Response Team: Summative Evaluation Report #2
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MacRae-Krisa, L. and Bertrand, L.D.
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- 2014
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9. Evaluation of the Elder Abuse Response Team: Summative Evaluation Report #1
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MacRae-Krisa, L. and Bertrand, L.D.
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- 2013
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10. Response to Editorial note on: Agreement of repeated motor and sensory scores at individual myotomes and dermatomes in young persons with spinal cord injury
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Krisa, L, primary, Gaughan, J, additional, Vogel, L, additional, Betz, R R, additional, and Mulcahey, M J, additional
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- 2012
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11. Agreement of repeated motor and sensory scores at individual myotomes and dermatomes in young persons with spinal cord injury
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Krisa, L, primary, Gaughan, J, additional, Vogel, L, additional, Betz, R R, additional, and Mulcahey, M J, additional
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- 2012
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12. Agreement of repeated motor and sensory scores at individual myotomes and dermatomes in young persons with spinal cord injury.
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Krisa, L, Gaughan, J, Vogel, L, Betz, R R, and Mulcahey, M J
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CONFIDENCE intervals , *LONGITUDINAL method , *MEDICAL cooperation , *RESEARCH , *RESEARCH funding , *SPINAL cord injuries , *STATISTICS , *INTER-observer reliability , *REPEATED measures design , *DESCRIPTIVE statistics , *DISEASE complications ,RESEARCH evaluation - Abstract
Study design:A prospective repeated measures multicenter study to determine reliability at individual spinal levels when applied to young persons with spinal cord injury (SCI).Objectives:To evaluate intra- and inter-rater agreement of repeated motor and sensory scores at individual spinal levels.Setting:Shriners Hospitals for Children-Philadelphia and Chicago, USAMethods:A total 189 youth with complete and incomplete SCI underwent four neurological exams by two different raters. Agreement between and within raters for each myotome and dermatome was evaluated for complete and incomplete SCI separately. Intraclass correlation coefficients and 95% confidence intervals were calculated.Results:Overall, both intra- and inter-rater agreement resulted in moderate-to-high agreement among myotomes. Subjects with complete SCI had moderate agreement for light touch (LT) and pin prick (PP) testing, whereas subjects with incomplete SCI had >60.0% of dermatomes resulting in poor agreement for PP testing.Conclusion:Overall, moderate-to-high agreement was found for muscle strength comparisons and moderate-to-poor agreement was found for PP and LT. [ABSTRACT FROM AUTHOR]
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- 2013
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13. Proceedings of the 2017 WAO Symposium on Hot Topics in Allergy: Pediatric & Regulatory Aspects
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Giovanni Traina, Rocco Luigi Valluzzi, Vincenzo Fierro, Carla Riccardi, Maria Cristina Artesani, Andrea De Vuono, Alessandro Fiocchi, Alberto G. Martelli, Luis Alberto Ríos, Christian R. Alcocer, Elsy Navarrete, Blanca Estela Del Rio Navarro, Victor Gonzalez, Berenice Velasco, Herberth J. Perez Aviles, Roberto Jose Fernandez, F. Cesar Pozo, Abdal Jabbar Farhan, Hasan Arshad, Ahmed Hussain, Olena Sharikadze, Olena Okhotnikova, Javier Alcover, Diego Rodriguez, Fernando Pineda, Ilan Dalal, Jenny Weinbrand-Goichberg, Shira Benor, Menachem Rottem, Shmuel Kivity, Sakura Sato, Noriyuki Yanagida, Motohiro Ebisawa, Tetiana Umanets, Youriy Antipkin, Vladyslava Barzylovich, Volodymyr Lapshyn, Mykola Umanets, Sergey Yuriev, Suzan Bekir, Tobias Pincock, Alberto Vieira Hernandez, Arnaldo Capriles Hulett, Mario Sánchez Borges, Fabiola Fabiano, Carlos Albarran, Rohit Goyal, Shilpa Gupta, Garg Gaurav, Allan T. Luskin, Noelle M. Griffin, Amy Wagelie-Steffen, Benjamin L. Trzaskoma, Susan L. Limb, William W. Busse, Robert S. Zeiger, Erika Gonzalez-Reyes, Thomas B. Casale, Bradley E. Chipps, Chizuko Sugizaki, Fumiko Goto, Akiko Yamaide, Kanako Mitsunaga, Minako Tomiita, Akira Hoshioka, Naoki Shimojo, Liviu L. Pop, Ioana-Mihaela Ciucǎ, Liviu Tǎmaş, Marilena Lazarescu, Corina Pienar, Fumiya Yamaide, Bahrul Fikri, Hironori Sato, Naoko Okishima, Miyabi Kobayashi, Mizuki Takai, Kotarou Nishigata, Ryou Yoda, Yu-ta Oana, Chifu Kajiwara, Moe Shimodaira, Tomoka Suzuki, Hiromi Iizawa, Koji Kamijo, Bijoya Karmakar, Swati Gupta Bhattacharya, Simona Blohlávková, Eliška Kopelentová, Petr Víšek, Jakub Štádler, Ivana Šetinová, Jana Novobílská, Krisa Lundelin, Seppo Salminen, Erika Isolauri, Tracy Pitt, Tamar Flanders, Marcos Peñalver, Patricia Martínez, Magdalena Lluch, Alfonso Malet, Young-Hee Nam, Hyun Jung Jin, Soo-Keol Lee, Prapasri Kulalert, Paskorn Sritipsukho, Jayanton Pathumanond, Krasimira Baynova, Marina Labella, Teresa De Aramburu, Manuel Prados, Leena Haanpää, Jasmin Aarnio, Merja Nermes, Piia af Ursin, Anne Kaljonen, Nandana Bala, Ketaki Bhagwat, James Hindley, Martin Chapman, Sivasankar Baalasubramanian, Lilijana Besednjak-Kocijančič, Koyel SenGupta, Evgeniya Antonova, Amanda M. Kong, Ahmar Iqbal, W. Gerald Teague, Benjamin Trzaskoma, Benjamin Ortiz, Brandee Paknis, Amar Iqbal, Karin Rosen, Stanley Szefler, Afaf Alblooshi, Suleiman Al-Hammadi, Arantza Vega, Raquel Gutiérrez-Rivas, Ana Maria Alonso, Juan Maria Beitia, Maria Belén Mateo, Remedios Cárdenas, Juan Jesús García-Domínguez, Raquel Pitchon dos Reis, Cristina Gonçalves Alvim, Claudia Andrade, Adriana Reis, Henrique Ribeiro, Carmen Panaitescu Bunu, Laura Marusciac, Sorin Paralescu, Paul Tamas, Carmen Panitescu Bunu, Enrique Martí Guadaño, Carolina Escobar Bolaños, Natalia Martí José, Pol Pau Casanovas, Gemma Biarnés Rib, Mariana Castells, Talía de Vicente Jiménez, Maurizio Mennini, Papola De Angelis, Francesca Rea, Monica Malamisura, Renato Tambucci, Luigi Dall’Oglio, Federica Del Chierico, Tania Napolitano, Silvia Reddel, Pamela Vernocchi, Angelo D’Ambrosio, Lorenza Putignani, Lamia Dahdah, Claudia Banzato, Luís Angel Echeverría Zudaire, Ana María Plaza, Montserrat Bosque García, Marcel Íbero, Oscar Mazzina, Valeria Marzano, Valeria Pecora, Pierluigi Koch, Valentina Pecora, Diletta Valentini, Francesca Santamaria, Rocco Valluzzi, Anwesha Mukherjee, Amit Kandhare, and Subhash Bodhankar
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Immunologic diseases. Allergy ,RC581-607 - Published
- 2017
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14. Response to Editorial note on: Agreement of repeated motor and sensory scores at individual myotomes and dermatomes in young persons with spinal cord injury.
- Author
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Krisa, L, Gaughan, J, Vogel, L, Betz, R R, and Mulcahey, M J
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RESEARCH methodology , *SPINAL cord injuries , *STATISTICS , *INTER-observer reliability , *DISEASE complications - Abstract
In this article authors L. Krisa et al. respond to an editorial comment which was written about their article "Agreement of Repeated Motor and Sensory Scores at Individual Myotomes and Dermatomes in Young Persons With Spinal Cord Injury". In their response the authors offer their opinions on research which was discussed in their article.
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- 2013
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15. Periaqueductal gray connectivity in spinal cord injury-induced neuropathic pain.
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Shoraka O, Syed M, Mandloi S, Thalheimer S, Kashani SN, Heller JE, Mohamed FB, Sharan AD, Talekar KS, Matias CM, Harrop JS, Krisa L, and Alizadeh M
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- Humans, Male, Female, Adult, Middle Aged, Neural Pathways physiopathology, Neural Pathways diagnostic imaging, Spinal Cord Injuries diagnostic imaging, Spinal Cord Injuries complications, Spinal Cord Injuries physiopathology, Periaqueductal Gray diagnostic imaging, Periaqueductal Gray physiopathology, Neuralgia etiology, Neuralgia diagnostic imaging, Neuralgia physiopathology, Magnetic Resonance Imaging
- Abstract
Background and Purpose: Neuropathic pain (NP) is a debilitating condition following spinal cord injury (SCI). The role of periaqueductal gray (PAG) in NP development following SCI remains underexplored. Using resting-state functional MRI (rsfMRI), our study aimed to demonstrate the alterations in functional connectivity (FC) of PAG in NP following SCI., Methods: Ten SCI patients (SCI + NP, n = 7, and SCI - NP, n = 3), alongside 10 healthy controls (HCs), were enrolled. rsfMRI was conducted followed by seed-to-voxel analysis using PAG as the seed region and then group-based analysis comprising three groups (SCI + NP, SCI - NP, and HC). Age and gender were considered as confounding variables., Results: Compared to HCs, SCI + NP demonstrated decreased FC between PAG and right insula, right frontal orbital cortex, right pallidum, dorsal raphe nucleus (DRN), red nuclei (RN), substantia nigra (SN), and ventral posterolateral (VPL) thalamic nuclei. Compared to SCI - NP, SCI + NP demonstrated increased FC between PAG and posterior cingulate cortex (PCC), hippocampus, cerebellar vermis lobules IV and V, and thalamic structures (posterior and lateral pulvinar, the mediodorsal nuclei, and the ventral lateral nuclei). Additionally, decreased FC between the PAG and VPL, geniculate bodies, intralaminar nuclei of thalamus, DRN, RN, SN, and prefrontal cortex was observed in this comparison., Conclusions: Altered FC between PAG and right anterior insula, VPL, DRN, RN, SN, cerebellar vermis lobules IV and V, frontal cortex, and PCC was associated with NP sequelae of SCI. Additionally, SCI was independently associated with decreased FC between PAG and right posterior insula, cerebellar lobules IV and V, and cerebellar vermis lobules III, IV, and V., (© 2024 The Author(s). Journal of Neuroimaging published by Wiley Periodicals LLC on behalf of American Society of Neuroimaging.)
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- 2024
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16. Multimodal functional imaging and clinical correlates of pain regions in chronic low-back pain patients treated with spinal cord stimulation: a pilot study.
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Shamli Oghli Y, Ashok A, Glener S, Ailes I, Syed M, Kang KC, Naghizadehkashani S, Fayed I, Mohamed FB, Talekar K, Krisa L, Wu C, Matias C, and Alizadeh M
- Abstract
Objective: Spinal cord stimulation (SCS) is an invasive treatment option for patients suffering from chronic low-back pain (cLBP). It is an effective treatment that has been shown to reduce pain and increase the quality of life in patients. However, the activation of pain processing regions of cLBP patients receiving SCS has not been assessed using objective, quantitative functional imaging techniques. The purpose of the present study was to compare quantitative resting-state (rs)-fMRI and arterial spin labeling (ASL) measures between SCS patients and healthy controls and to correlate clinical measures with quantitative multimodal imaging indices in pain regions., Methods: Multi-delay 3D GRASE pseudo-continuous ASL and rs-fMRI data were acquired from five patients post-SCS with cLBP and five healthy controls. Three ASL measures and four rs-fMRI measures were derived and normalized into MNI space and smoothed. Averaged values for each measure from a pain atlas were extracted and compared between patients and controls. Clinical pain scores assessing intensity, sensitization, and catastrophizing, as well as others assessing global pain effects (sleep quality, disability, anxiety, and depression), were obtained in patients and correlated with pain regions using linear regression analysis., Results: Arterial transit time derived from ASL and several rs-fMRI measures were significantly different in patients in regions involved with sensation (primary somatosensory cortex and ventral posterolateral thalamus [VPL]), pain input (posterior short gyrus of the insula [PS]), cognition (dorsolateral prefrontal cortex [DLPC] and posterior cingulate cortex [PCC]), and fear/stress response (hippocampus and hypothalamus). Unidimensional pain rating and sensitization scores were linearly associated with PS, VPL, DLPC, PCC, and/or amygdala activity in cLBP patients., Conclusion: The present results provide evidence that ASL and rs-fMRI can contrast functional activation in pain regions of cLBP patients receiving SCS and healthy subjects, and they can be associated with clinical pain evaluations as quantitative assessment tools., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Shamli Oghli, Ashok, Glener, Ailes, Syed, Kang, Naghizadehkashani, Fayed, Mohamed, Talekar, Krisa, Wu, Matias and Alizadeh.)
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- 2024
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17. Harmonization of Longitudinal Diffusion Tensor Imaging Data of the Pediatric Cervical and Thoracic Spinal Cord at 3T Using Longitudinal ComBat.
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Li Y, Middleton DM, Chen A, Shinohara RT, Krisa L, Faro SH, Mulcahey MJ, and Mohamed FB
- Abstract
Diffusion tensor imaging (DTI) of the spinal cord has been extensively used to identify biomarkers for spinal cord pathology. Previously, the longitudinal ComBat (longComBat) technique was examined to reduce scanner effects in multi-site, multi-scanner spinal cord DTI data. This study aimed to assess its effectiveness on longitudinal scans using a single-scanner pediatric dataset, including healthy and spinal cord injury (SCI) subjects. Two identical datasets were collected from 42 healthy and 27 SCI subjects with a 2-hour interval between scans on a 3T Siemens MRI scanner. Axial DTI images of the entire cervical and thoracic spinal cord were obtained, and various average diffusion tensor metrics (FA, MD, RD, & AD) were measured at each vertebral level. Pearson correlation and intraclass correlation coefficients were used to evaluate inter- and intra-subject agreement pre- and post-harmonization. Minimal improvement in agreement was observed with the mean square residual (MSR) model, while the restricted maximum likelihood estimator (REML) model showed reduced intra-subject agreement in all the tensor metrics. The significant variability between longitudinal DTI scans within a single scanner was likely due to physiological motion rather than scanner effects. Post-harmonization using the longComBat MSR model showed limited improvement in agreement., Competing Interests: Additional information Competing interests The authors declare no competing interests.
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- 2024
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18. Exploring Functional Connectivity in Chronic Spinal Cord Injury Patients With Neuropathic Pain Versus Without Neuropathic Pain.
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Mandloi S, Syed M, Ailes I, Shoraka O, Leiby B, Miao J, Thalheimer S, Heller J, Mohamed FB, Sharan A, Harrop J, Krisa L, and Alizadeh M
- Abstract
The great majority of spinal cord injury (SCI) patients have debilitating chronic pain. Despite decades of research, these pain pathways of neuropathic pain (NP) are unknown. SCI patients have been shown to have abnormal brain pain pathways. We hypothesize that SCI NP patients' pain matrix is altered compared to SCI patients without NP. This study examines the functional connectivity (FC) in SCI patients with moderate-severe chronic NP compared to SCI patients with mild-no NP. These groups were compared to control subjects. The Neuropathic Pain Questionnaire and neurological evaluation based on the International Standard Neurological Classification of SCI were utilized to define the severity and level of injury. Of the 10 SCI patients, 7 (48.6 ± 17.02 years old, 6 male and 1 female) indicated that they had NP and 3 did not have NP (39.33 ± 8.08 years old, 2 male and 1 female). Ten uninjured neurologically intact participants were used as controls (24.8 ± 4.61 years old, 5 male and 5 female). FC metrics were obtained from the comparisons of resting-state functional magnetic resonance imaging among our various groups (controls, SCI with NP, and SCI without NP). For each comparison, a region-of-interest (ROI)-to-ROI connectivity analysis was pursued, encompassing a total of 175 ROIs based on a customized atlas derived from the AAL3 atlas. The analysis accounted for covariates such as age and sex. To correct for multiple comparisons, a strict Bonferroni correction was applied with a significance level of p < 0.05/NROIs. When comparing SCI patients with moderate-to-severe pain to those with mild-to-no pain, specific thalamic nuclei had altered connections. These nuclei included: medial pulvinar; lateral pulvinar; medial geniculate nucleus; lateral geniculate nucleus; and mediodorsal magnocellular nucleus. There was increased FC between the lateral geniculate nucleus and the anteroventral nucleus in NP post-SCI. Our analysis additionally highlights the relationships between the frontal lobe and temporal lobe with pain. This study successfully identifies thalamic neuroplastic changes that occur in patients with SCI who develop NP. It additionally underscores the pain matrix and involvement of the frontal and temporal lobes as well. Our findings complement that the development of NP post-SCI involves cognitive, emotional, and behavioral influences., Competing Interests: Ashwini Sharan has received support from Cerebral Therapeutics, Mudjala/Defuse, Tigerlabs, Neuspera, and Neurotargeting and as the Chief Medical Officer of the Medtronic Neuromodulation Operating Unit., (© Shreya Mandloi et al., 2024; Published by Mary Ann Liebert, Inc.)
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- 2024
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19. Metal artifact reduction around cervical spine implant using diffusion tensor imaging at 3T: A phantom study.
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Tounekti S, Alizadeh M, Middleton D, Harrop JS, Hiba B, Krisa L, Mekkaoui C, and Mohamed FB
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- Humans, Diffusion Magnetic Resonance Imaging methods, Spinal Cord, Echo-Planar Imaging methods, Cervical Vertebrae diagnostic imaging, Cervical Vertebrae surgery, Diffusion Tensor Imaging methods, Artifacts
- Abstract
Purpose: Diffusion MRI continues to play a key role in non-invasively assessing spinal cord integrity and pre-operative injury evaluation. However, post-operative Diffusion Tensor Imaging (DTI) acquisition of patients with metal implants results in severe geometric distortion. We propose and demonstrate a method to alleviate the technical challenges facing the acquisition of DTI on post-operative cases and longitudinal evaluation of therapeutics., Material and Methods: The described technique is based on the combination of the reduced Field-Of-View (rFOV) strategy and the phase segmented EPI, termed rFOV-PS-EPI. A custom-built phantom based on a cervical spine model with metal implants was used to collect DTI data at 3 Tesla scanner using: rFOV-PS-EPI, reduced Field-Of-View single-shot EPI (rFOV-SS-EPI), and conventional full FOV techniques including SS-EPI, PS-EPI, and readout-segmented EPI (RS-EPI). Geometric distortion, SNR, and signal void were assessed to evaluate images and compare the sequences. A two-sample t-test was performed with p-value of 0.05 or less to indicate statistical significance., Results: The reduced FOV techniques showed better capability to reduce distortions compared to the Full FOV techniques. The rFOV-PS-EPI method provided DTI images of the phantom at the level of the hardware whereas the conventional rFOV-SS-EPI is useful only when the metal is approximately 20 mm away. In addition, compared to the rFOV-SS-EPI technique, the suggested approach produced smaller signal voids area as well as significantly reduced geometric distortion in Circularity (p < 0.005) and Eccentricity (p < 0.005) measurements. No statistically significant differences were found for these geometric distortion measurements between the rFOV-PS-EPI DTI sequence and conventional structural T2 images (p > 0.05)., Conclusion: The combination of rFOV and a phase-segmented acquisition approach is effective for reducing metal-induced distortions in DTI scan on spinal cord with metal hardware at 3 T., Competing Interests: Declaration of Competing Interest We have no conflict of interests to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)
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- 2024
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20. Harmonization of multi-site diffusion tensor imaging data for cervical and thoracic spinal cord at 1.5 T and 3 T using longitudinal ComBat.
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Middleton DM, Li Y, Chen A, Shinohara R, Fisher J, Krisa L, Elliot M, Faro SH, Woo JH, Flanders AE, and Mohamed FB
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- Adult, Humans, Diffusion Tensor Imaging methods, Reproducibility of Results, Spinal Cord diagnostic imaging, Diffusion Magnetic Resonance Imaging methods, Spinal Cord Injuries, Cervical Cord diagnostic imaging
- Abstract
MRI scanner hardware, field strengths, and sequence parameters are major variables in diffusion studies of the spinal cord. Reliability between scanners is not well known, particularly for the thoracic cord. DTI data was collected for the entire cervical and thoracic spinal cord in thirty healthy adult subjects with different MR vendors and field strengths. DTI metrics were extracted and averaged for all slices within each vertebral level. Metrics were examined for variability and then harmonized using longitudinal ComBat (longComBat). Four scanners were used: Siemens 3 T Prisma, Siemens 1.5 T Avanto, Philips 3 T Ingenia, Philips 1.5 T Achieva. Average full cord diffusion values/standard deviation for all subjects and scanners were FA: 0.63, σ = 0.10, MD: 1.11, σ = 0.12 × 10
-3 mm2 /s, AD: 1.98, σ = 0.55 × 10-3 mm2 /s, RD: 0.67, σ = 0.31 × 10-3 mm2 /s. FA metrics averaged for all subjects by level were relatively consistent across scanners, but large variability was found in diffusivity measures. Coefficients of variation were lowest in the cervical region, and relatively lower for FA than diffusivity measures. Harmonized metrics showed greatly improved agreement between scanners. Variability in DTI of the spinal cord arises from scanner hardware differences, pulse sequence differences, physiological motion, and subject compliance. The use of longComBat resulted in large improvement in agreement of all DTI metrics between scanners. This study shows the importance of harmonization of diffusion data in the spinal cord and potential for longitudinal and multisite clinical research and clinical trials., (© 2023. The Author(s).)- Published
- 2023
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21. Correlations of diffusion tensor imaging and clinical measures with spinal cord cross-sectional area measurements in pediatric spinal cord injury patients.
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Middleton DM, Shahrampour S, Krisa L, Liu W, Nair G, Jacobson S, Conklin CJ, Alizadeh M, Faro SH, Mulcahey MJ, and Mohamed FB
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- Humans, Child, Diffusion Tensor Imaging methods, Spinal Cord diagnostic imaging, Spinal Cord pathology, Prognosis, Spinal Cord Injuries diagnostic imaging, Spinal Cord Injuries pathology
- Abstract
Purpose: The purpose of this work was to employ a semi-automatic method for measuring spinal cord cross-sectional area (SCCSA) and investigate the correlations between diffusion tensor imaging (DTI) metrics and SCCSA for the cervical and thoracic spinal cord for typically developing pediatric subjects and pediatric subject with spinal cord injury., Methods: Ten typically developing (TD) pediatric subjects and ten pediatric subjects with spinal cord injury (SCI) were imaged using a Siemens Verio 3 T MR scanner to acquire DTI and high-resolution anatomic scans covering the cervical and thoracic spinal cord (C1-T12). SCCSA was measured using a semi-automated edge detection algorithm for the entire spinal cord. DTI metrics were obtained from whole cord axial ROIs at each vertebral level. SCCSA measures were compared to DTI metrics by vertebral level throughout the entire cord, and above and below the injury site. Correlation analysis was performed to compare SCCSA, DTI and clinical measures as determined by the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) examination., Results: In subjects with SCI, FA and SCCSA had a positive correlation (r = 0.81, P < 0.01), while RD and SCCSA had a negative correlation (r = -0.68, P = 0.02) for the full spinal cord. FA and SCCSA were correlated above (r = 0.56, P < 0.01) and below (r = 0.54, P < 0.01) the injury site. TD subjects showed negative correlations between AD and SCCSA (r = -0.73, P = 0.01) and RD and SCCSA (r = -0.79, P < 0.01)., Conclusion: The ability to quickly and effectively measure SCCSA in subjects with SCI has the potential to allow for a better understanding of the progression of atrophy following a SCI. Correlations between cord cross section and DTI metrics by vertebral level suggest that imaging inferior and superior to lesion may yield useful information for diagnosis and prognosis.
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- 2023
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22. The role of the insula in chronic pain following spinal cord injury: A resting-state fMRI study.
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Mandloi S, Syed M, Shoraka O, Ailes I, Kang KC, Sathe A, Heller J, Thalheimer S, Mohamed FB, Sharan A, Harrop J, Krisa L, Matias C, and Alizadeh M
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- Humans, Male, Female, Magnetic Resonance Imaging methods, Frontal Lobe, Nerve Net diagnostic imaging, Chronic Pain diagnostic imaging, Chronic Pain etiology, Spinal Cord Injuries complications, Spinal Cord Injuries diagnostic imaging
- Abstract
Background and Purpose: Spinal cord injury (SCI) results in the loss of motor and sensory function from disconnections between efferent and afferent pathways. Most SCI patients are affected with chronic neuropathic pain, but there is a paucity of data concerning neuroplastic changes following SCI. Chronic pain disrupts default networks and is associated with abnormal insular connectivity. The posterior insula (PI) is associated with the degree of pain and intensity of pain. The anterior insula (AI) is related to signal changes. Comprehension of SCI pain mechanisms is essential to elucidate effective treatment options., Methods: This study examines the insular gyri functional connectivity (FC) of seven (five male, two female) SCI participants with moderate-severe chronic pain compared to 10 (five male, five female) healthy controls (HC). All subjects had 3-Tesla MRI performed and resting-state functional MRI (fMRI) was acquired. FC metrics were obtained from the comparisons of resting-state fMRI among our various groups. A seed-to-voxel analysis was pursued, encompassing six gyri of the insula. For multiple comparisons, a correction was applied with a significance level of p < .05., Results: There were significant differences in FC of the insula between SCI participants with chronic pain compared with HC. In the SCI participants, there was hyperconnectivity of the AI and PI to the frontal pole. In addition, there was increased FC noted between the PI and the anterior cingulate cortex. Hyperconnectivity was also observed between the AI and the occipital cortex., Conclusions: These findings illustrate that there is a complex hyperconnectivity and modulation of pain pathways after traumatic SCI., (© 2023 The Authors. Journal of Neuroimaging published by Wiley Periodicals LLC on behalf of American Society of Neuroimaging.)
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- 2023
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23. Connecting Researchers and Clinicians Before Connecting the Injured Spinal Cord.
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Krisa L, Witoslawski E, Jones L, Mulcahey MJ, and Fouad K
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- Animals, Humans, Exercise, Consensus, Spinal Cord Injuries rehabilitation
- Abstract
Background: Translating research findings from animal models of spinal cord injury (SCI) to humans is a challenging enterprise. It is likely that differences in the use of common terms contribute to this., Objectives: The purpose of this study was to identify how scientists and clinicians define terms used across the research and clinical care continuum., Methods: We utilized the Delphi technique to develop consensus on the opinions of experts (defined as researchers and/or clinicians working in the field of SCI) through a series of structured, iterative surveys. A focus group of stakeholders developed the terms on the initial survey. Results were used to create definitions and formulate questions for a second and third survey., Results: Survey 1 yielded one definition for eight terms and multiple definitions for six terms in addition to three new terms that respondents believed should be defined. In Survey 2, definitions for eight terms reached at least 80% agreement: anatomically complete spinal cord injury, functionally complete spinal cord injury, neuromodulation, physical exercise, physical rehabilitation, plasticity, task specificity, and training intensity. Consensus was not reached for six terms. In Survey 3, definitions for seven additional terms reached at least 80% agreement: recovery, repair, compensation, regeneration, physical function, physiological function, and chronic . There were three terms that did not reach agreement after the three rounds: acute, translational research , and sprouting ., Conclusion: We found that different terminology contributes to the gap between preclinical and clinical research and clinical application. This suggests that increased communication among different disciplines could be a way to advance the field., Competing Interests: Conflicts of Interest The authors report no conflicts of interest., (© 2023 American Spinal Injury Association.)
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- 2023
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24. Case report: Utilizing diffusion-weighted MRI on a patient with chronic low back pain treated with spinal cord stimulation.
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Ailes I, Syed M, Matias CM, Krisa L, Miao J, Sathe A, Fayed I, Alhussein A, Natale P, Mohamed FB, Talekar K, and Alizadeh M
- Abstract
Diffusion-weighted magnetic resonance imaging (dwMRI) has increasingly demonstrated greater utility in analyzing neuronal microstructure. In patients with chronic low back pain (cLBP), using dwMRI to observe neuronal microstructure can lead to non-invasive biomarkers which could provide clinicians with an objective quantitative prognostic tool. In this case report, we investigated dwMRI for the development of non-invasive biomarkers by conducting a region-based analysis of a 55-year-old male patient with failed back surgery syndrome (FBSS) treated with spinal cord stimulation (SCS). We hypothesized that dwMRI could safely generate quantitative data reflecting cerebral microstructural alterations driven by neuromodulation. Neuroimaging was performed at 6- and 12- months post-SCS implantation. The quantitative maps generated included diffusion tensor imaging (DTI) parameters; fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) computed from whole brain tractography. To examine specific areas of the brain, 44 regions of interest (ROIs), collectively representing the pain NeuroMatrix, were extracted and registered to the patient's diffusion space. Average diffusion indices were calculated from the ROIs at both 6- and 12- months. Regions with >10% relative change in at least 3 of the 4 maps were reported. Using this selection criterion, 8 ROIs demonstrated over 10% relative changes. These ROIs were mainly located in the insular gyri. In addition to the quantitative data, a series of questionnaires were administered during the 6- and 12-month visits to assess pain intensity, functional disability, and quality of life. Overall improvements were observed in these components, with the Pain Catastrophizing Scale (PCS) displaying the greatest change. Lastly, we demonstrated the safety of dwMRI for a patient with SCS. In summary, the results from the case report prompt further investigation in applying dwMRI in a larger cohort to better correlate the influence of SCS with brain microstructural alterations, supporting the utility of dwMRI to generate non-invasive biomarkers for prognostication., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Ailes, Syed, Matias, Krisa, Miao, Sathe, Fayed, Alhussein, Natale, Mohamed, Talekar and Alizadeh.)
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- 2023
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25. Metal Artifact Reduction Around Cervical Spine Implant Using Diffusion Tensor Imaging at 3T: A Phantom Study.
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Tounekti S, Alizadeh M, Middleton D, Harrop JS, Bassem H, Krisa L, Mekkaoui C, and Mohamed FB
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Diffusion MRI continues to play a key role in non-invasively assessing spinal cord integrity and pre-operative injury evaluation. However, post-operative Diffusion Tensor Imaging (DTI) acquisition of a patient with a metal implant results in severe geometric image distortion. A method has been proposed here to alleviate the technical challenges facing the acquisition of DTI in post-operative cases and to evaluate longitudinal therapeutics. The described technique is based on the combination of the reduced Field-Of-View (rFOV) strategy and the phase segmented acquisition scheme (rFOV-PS-EPI) for significantly mitigating metal-induced distortions. A custom-built phantom based on spine model with metal implant was used to collect high-resolution DTI data at 3 Tesla scanner using a home-grown diffusion MRI pulse sequence, rFOV-PS-EPI, single-shot (rFOV-SS-EPI), and the conventional full FOV techniques including SS-EPI, PS-EPI, and the readout-segmented (RS-EPI). This newly developed method provides high-resolution images with significant reduced metal-induced artifacts. In contrast to the other techniques, the rFOV-PS-EPI allows DTI measurement at the level of the metal hardware whereas the current rFOV-SS-EPI is useful when the metal is approximately 20 mm away. The developed approach enables high-resolution DTI in patients with metal implant., Competing Interests: Declarations Competing interests We have no conflict of interests to declare.
- Published
- 2023
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26. Case report: The promising application of dynamic functional connectivity analysis on an individual with failed back surgery syndrome.
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Miao J, Ailes I, Krisa L, Fleming K, Middleton D, Talekar K, Natale P, Mohamed FB, Hines K, Matias CM, and Alizadeh M
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Failed back surgery syndrome (FBSS), a chronic neuropathic pain condition, is a common indication for spinal cord stimulation (SCS). However, the mechanisms of SCS, especially its effects on supraspinal/brain functional connectivity, are still not fully understood. Resting state functional magnetic resonance imaging (rsfMRI) studies have shown characteristics in patients with chronic low back pain (cLBP). In this case study, we performed rsfMRI scanning (3.0 T) on an FBSS patient, who presented with chronic low back and leg pain following her previous lumbar microdiscectomy and had undergone permanent SCS. Appropriate MRI safety measures were undertaken to scan this subject. Seed-based functional connectivity (FC) was performed on the rsfMRI data acquired from the FBSS subject, and then compared to a group of 17 healthy controls. Seeds were identified by an atlas of resting state networks (RSNs), which is composed of 32 regions grouped into 8 networks. Sliding-window method and k-means clustering were used in dynamic FC analysis, which resulted in 4 brain states for each group. Our results demonstrated the safety and feasibility of 3T MRI scanning in a patient with implanted SCS system. Compared to the brain states of healthy controls, the FBSS subject presented very different FC patterns in less frequent brain states. The mean dwell time of brain states showed distinct distributions: the FBSS subject seemed to prefer a single state over the others. Although future studies with large sample sizes are needed to make statistical conclusions, our findings demonstrated the promising application of dynamic FC to provide more granularity with FC changes associated with different brain states in chronic pain., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Miao, Ailes, Krisa, Fleming, Middleton, Talekar, Natale, Mohamed, Hines, Matias and Alizadeh.)
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- 2022
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27. DTI of chronic spinal cord injury in children without MRI abnormalities (SCIWOMR) and with pathology on MRI and comparison to severity of motor impairment.
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Faro SH, Saksena S, Krisa L, Middleton DM, Alizadeh M, Finsterbusch J, Flanders AE, Talekar K, Mulcahey MJ, and Mohamed FB
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- Adolescent, Adult, Child, Cohort Studies, Diffusion Tensor Imaging methods, Humans, Magnetic Resonance Imaging methods, Spinal Cord diagnostic imaging, Spinal Cord pathology, Motor Disorders pathology, Spinal Cord Injuries complications, Spinal Cord Injuries diagnostic imaging, Spinal Cord Injuries pathology
- Abstract
Study Design: This investigation was a cohort study that included: 36 typically developing (TD) children and 19 children with spinal cord lesions who underwent spinal cord MRI., Objectives: To investigate diffusion tensor imaging (DTI) cervical and thoracic spinal cord changes in pediatric patients that have clinically traumatic and non-traumatic spinal cord injury (SCI) without MR (SCIWOMR) abnormalities., Setting: Thomas Jefferson University, Temple University, Shriners Hospitals for Children all in Philadelphia, USA., Methods: 36 TD children and 19 children with spinal cord lesions that represent either a chronic traumatic acquired SCI or chronic non-traumatic SCI (≥6 months post injury), age range, 6-16 years who underwent cervical and thoracic spinal cord MRI in 2014-2017. Additionally DTI was correlated to clinical American Spinal Injury Association Impairment Scale (AIS)., Results: Both SCIWOMR and MRI positive (+) groups showed abnormal FA and RD DTI values in the adjacent MRI-normal appearing segments of cephalad and caudal spinal cord compared to TD. The FA values demonstrated perilesional abnormal DTI findings in the middle and proximal segments of the cephalad and caudal cord in the SCIWOMR AIS A/B group compared to SCIWOMR AIS C/D group., Conclusions: We found DTI changes in children with SCIWOMR with different causes of spinal lesions. We also investigated the relationship between DTI and clinical AIS scores. This study further examined the potential diagnostic value of DTI and should be translatable to adults with spinal cord lesions., (© 2022. The Author(s), under exclusive licence to International Spinal Cord Society.)
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- 2022
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28. Clinical Utility of Diffusion Tensor Imaging as a Biomarker to Identify Microstructural Changes in Pediatric Spinal Cord Injury.
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Krisa L, Middleton DM, Saksena S, Faro SH, Leiby BE, Mohamed FB, and Mulcahey MJ
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- Biomarkers, Child, Humans, Prospective Studies, Diffusion Tensor Imaging methods, Spinal Cord Injuries diagnostic imaging
- Abstract
Background: Lack of clarity about the neurological consequence of spinal cord injury (SCI) in children causes speculation about diagnoses, recovery potential, and treatment effectiveness. Diffusion tensor imaging (DTI) has shown promising results as a biomarker to evaluate spinal cord integrity at a microstructural level., Objectives: To look at the difference between pediatric participants with and without SCI to determine which DTI metrics best categorize spinal cord tissue damage and to correlate DTI metrics with two clinical measures: Capabilities of the Upper Extremity Test (CUE-T) and Spinal Cord Independence Measure version III (SCIM-III)., Methods: This single-site, prospective study included pediatric participants with SCI ( n = 26) and typically developed (TD) control subjects ( n = 36). All participants underwent two magnetic resonance imaging (MRI) scans on a 3T MR scanner. Participants with SCI also completed the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI), CUE-T, and SCIM-III outcomes measures., Results: This study found significant strength of association between fractional anisotropy (FA) and upper extremity muscle strength (UEMS) in participants with SCI. Most DTI parameters showed a significant difference between participants with SCI and TD participants and a moderate correlation with the CUE-T total score. Regional effects on group differences were found to be significant., Conclusion: This study demonstrates the strength of association between DTI parameters and clinical measures in the pedantic SCI population. It illustrates DTI as a potential biomarker of SCI location and severity in the pediatric SCI population., Competing Interests: Conflicts of Interest All authors received funding from the National Institutes of Health (via their institution via salary and fringe benefits) to complete the work outlined in this article. MJ Mulcahey is an associate editor for Topics in Spinal Cord Injury Rehabilitation., (© 2022 American Spinal Injury Association.)
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- 2022
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29. Brain White Matter Abnormality Induced by Chronic Spinal Cord Injury in the Pediatric Population: A Preliminary Tract-based Spatial Statistic Study.
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Fisher J, Alizadeh M, Middleton D, Matias CM, Mulcahey MJ, Calhoun-Thielen C, Mohamed FB, and Krisa L
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- Adolescent, Adult, Anisotropy, Child, Diffusion Tensor Imaging, Humans, Young Adult, Spinal Cord Injuries diagnostic imaging, White Matter diagnostic imaging
- Abstract
Objectives: Tract-based spatial statistics (TBSS) is a diffusion tensor imaging (DTI)-based processing technique that aims to improve the objectivity and interpretability of analysis of multisubject diffusion imaging studies. This study used TBSS to measure quantitative changes in brain white matter structures following spinal cord injury (SCI). Methods: Eighteen SCI subjects aged 8-20 years old (mean age, 16.5 years) were scanned using a conventional single-shot EPI DTI protocol using a 3.0T Siemens MR scanner. All participants underwent a complete International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) examination to determine the level and severity of injury. Five participants were classified as American Spinal Injury Association Impairment Scale (AIS) A, nine as AIS B, and four as AIS C/D. Imaging parameters used for data collection were as follows: 20 directions, b = 1000 s/mm
2 , voxel size = 1.8 mm x 1.8 mm, slice thickness = 5 mm, TE = 95 ms, TR = 4300 ms, slices = 30, TA = 4:45 min. To generate TBSS, nonparametric permutation tests were used for voxel-wise statistical analysis of the fractional anisotropy (FA) skeletons between AIS groups. A two-tailed t test was applied to extract voxels with significant differences at p < .05. Results: Notable significant changes occurred throughout the corticospinal, spinothalamic, and dorsal column/medial lemniscus tracts. Altered regions in the temporal, occipital, and parietal lobes were also identified. Conclusion: These results suggest that white matter structures are altered differently between people with different AIS classifications. TBSS has the potential to serve as a screening tool to identify white matter changes in regions of interest., Competing Interests: Conflicts of Interest Dr. Mulcahey reports grants from NINDS and from Craig H Neilsen Foundation during the conduct of the study. The other authors report no conflicts of interest., (© 2021 American Spinal Injury Association.)- Published
- 2021
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30. Atlas-Based Quantification of DTI Measures in a Typically Developing Pediatric Spinal Cord.
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Shahrampour S, De Leener B, Alizadeh M, Middleton D, Krisa L, Flanders AE, Faro SH, Cohen-Adad J, and Mohamed FB
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- Adolescent, Adult, Anisotropy, Child, Diffusion Tensor Imaging, Humans, Spinal Cord diagnostic imaging, Pediatrics, White Matter diagnostic imaging
- Abstract
Background and Purpose: Multi-parametric MRI, provides a variety of biomarkers sensitive to white matter integrity, However, spinal cord MRI data in pediatrics is rare compared to adults. The purpose of this work was 3-fold: 1) to develop a processing pipeline for atlas-based generation of the typically developing pediatric spinal cord WM tracts, 2) to derive atlas-based normative values of the DTI indices for various WM pathways, and 3) to investigate age-related changes in the obtained normative DTI indices along the extracted tracts., Materials and Methods: DTI scans of 30 typically developing subjects (age range, 6-16 years) were acquired on a 3T MR imaging scanner. The data were registered to the PAM50 template in the Spinal Cord Toolbox. Next, the DTI indices for various WM regions were extracted at a single section centered at the C3 vertebral body in all the 30 subjects. Finally, an ANOVA test was performed to examine the effects of the following: 1) laterality, 2) functionality, and 3) age, with DTI-derived indices in 34 extracted WM regions., Results: A postprocessing pipeline was developed and validated to delineate pediatric spinal cord WM tracts. The results of ANOVA on fractional anisotropy values showed no effect for laterality ( P = .72) but an effect for functionality ( P < .001) when comparing the 30 primary WM labels. There was a significant ( P < .05) effect of age and maturity of the left spinothalamic tract on mean diffusivity, radial diffusivity, and axial diffusivity values., Conclusions: The proposed automated pipeline in this study incorporates unique postprocessing steps followed by template registration and quantification of DTI metrics using atlas-based regions. This method eliminates the need for manual ROI analysis of WM tracts and, therefore, increases the accuracy and speed of the measurements., (© 2021 by American Journal of Neuroradiology.)
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- 2021
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31. Graph theoretical structural connectome analysis of the brain in patients with chronic spinal cord injury: preliminary investigation.
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Alizadeh M, Manmatharayan AR, Johnston T, Thalheimer S, Finley M, Detloff M, Sharan A, Harrop J, Newburg A, Krisa L, and Mohamed FB
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- Adult, Brain diagnostic imaging, Diffusion Tensor Imaging, Humans, Retrospective Studies, Connectome, Spinal Cord Injuries diagnostic imaging
- Abstract
Study Design: Retrospective study., Objectives: We aimed to characterize the convergent disruptions of the structural connectivity based on network modeling technique (i.e., graph theory) to identify significant changes in network organization/reorganization between uninjured and chronic spinal cord injury (SCI) participants., Setting: USA., Methods: Ten adult participants including 4 with chronic SCI and 6 uninjured were scanned using a multi-shell diffusion imaging on a 3.0 T MR scanner. Whole brain structural connectivity matrix was estimated by performing the quantification of the number of white matter fibers (called edges) connecting each possible pair of brain region (called nodes). Brain regions were defined according to Desikan-Killiany cortical atlas. Using connectivity matrix, connectivity strength as well as six different graph theoretical measurements were computed for each participant. They include: (1) global efficiency; (2) local efficiency; (3) degree; (4) betweenness centrality; (5) average shortest length and (6) clustering coefficient. Finally network based statistics was applied to extract nodes/connections with significant differences between groups (uninjured vs SCI)., Results: The SCI group showed significant decreases in betweenness centrality in the left precentral gyrus (T-score=2.98, p value=0.02), and the right caudal middle frontal gyrus (score = 2.35, p value=0.047). It also showed significant decrease in left transverse temporal gyrus (T-score=2.36, p value=0.046) in clustering coefficient. In addition, altered regions in the occipital and parietal lobe were also identified., Conclusion: These results suggest that not only local but also global alterations of the white matter occur after SCI. The proposed modeling technique has the potential to serve as a screening tool to identify any areas of the brain affected after SCI., (© 2021. The Author(s), under exclusive licence to International Spinal Cord Society.)
- Published
- 2021
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32. Validation of the National Institute of Neurological Disorders and Stroke Spinal Cord Injury MRI Common Data Elements Instrument.
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Fisher J, Krisa L, Middleton DM, Leiby BE, Harrop JS, Shah LM, Schwartz ED, Doshi A, Faro SH, Mohamed FB, and Flanders AE
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- Cervical Vertebrae, Humans, Magnetic Resonance Imaging, National Institute of Neurological Disorders and Stroke (U.S.), Reproducibility of Results, Spinal Cord, United States epidemiology, Common Data Elements, Spinal Cord Injuries diagnostic imaging
- Abstract
Background and Purpose: The National Institute of Neurological Disorders and Stroke common data elements initiative was created to provide a consistent method for recording and reporting observations related to neurologic diseases in clinical trials. The purpose of this study is to validate the subset of common data elements related to MR imaging evaluation of acute spinal cord injury., Materials and Methods: Thirty-five cervical and thoracic MR imaging studies of patients with acute spinal cord injury were evaluated independently in 2 rounds by 5 expert reviewers. Intra- and interrater agreement were calculated for 17 distinct MR imaging observations related to spinal cord injury. These included ordinal, categoric, and continuous measures related to the length and location of spinal cord hemorrhage and edema as well as spinal canal and cord measurements. Level of agreement was calculated using the interclass correlation coefficient and kappa., Results: The ordinal common data elements spinal cord injury elements for lesion center and rostral or caudal extent of edema or hemorrhage demonstrated agreement ranging from interclass correlation coefficient 0.68 to 0.99. Reproducibility ranged from 0.95 to 1.00. Moderate agreement was observed for absolute length of hemorrhage and edema (0.54 to 0.60) with good reproducibility (0.78 to 0.83). Agreement for the Brain and Spinal Injury Center score showed the lowest interrater agreement with an overall kappa of 0.27 (0.20, 0.34). For 7 of the 8 variables related to spinal cord injury, agreement improved between the first and second evaluation. Continuous diameter measures of the spinal cord and spinal canal using interclass correlation coefficient varied substantially (0.23 to 0.83)., Conclusions: Agreement was more consistent for the ordinal measures of spinal cord injury than continuous measures. Good to excellent agreement on length and location of spinal cord hemorrhage and edema can be achieved with ordinal measures alone., (© 2021 by American Journal of Neuroradiology.)
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- 2021
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33. Diffusion Tensor Imaging Assessment of Regional White Matter Changes in the Cervical and Thoracic Spinal Cord in Pediatric Subjects.
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Saksena S, Mohamed FB, Middleton DM, Krisa L, Alizadeh M, Shahrampour S, Conklin CJ, Flanders A, Finsterbusch J, Mulcahey MJ, and Faro SH
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- Adolescent, Cervical Cord pathology, Child, Diffusion Tensor Imaging methods, Female, Humans, Male, Neuroimaging methods, Retrospective Studies, Spinal Cord pathology, White Matter pathology, Cervical Cord diagnostic imaging, Spinal Cord diagnostic imaging, Spinal Cord Injuries diagnostic imaging, Spinal Cord Injuries pathology, White Matter diagnostic imaging
- Abstract
There are no studies to date,describing changes in the diffusion tensor imaging (DTI) metrics of the white matter (WM) regions of the entire cervical and thoracic spinal cord (SC) remote from the lesion in pediatric spinal cord injury (SCI) subjects. The purpose of this study was to determine whether DTI at sites cephalad and caudal to a lesion provides measures of cord abnormalities in children with chronic SCI. A retrospective study included 10 typically developing subjects (TD) and 10 subjects with chronic SCI who underwent SC imaging in 2014-2017. Axial diffusion tensor images using an inner field of view DTI sequence were acquired to cover the entire cervical and thoracic SC. Regions of interest were drawn on the SC WM: right and left lateral (motor), ventral (motor), and dorsal (sensory) tracts. To detect differences in DTI metrics between TD and SCI of the cord, a one way analysis of variance with pooled t test was performed. A stepwise regression analysis was performed to assess the correlation between DTI metrics and clinical scores. In motor and sensory tracts, fractional anisotropy (FA) and axial diffusivity (AD) were significantly decreased in the proximal segments of the caudal cord. In motor tracts cephalad to the lesion, FA was significantly decreased whereas AD was significantly increased in the proximal segment; however, AD was decreased in the distal and middle segments. International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) total score was significantly correlated with FA and AD of the motor and sensory tracts cephalad to the lesion. This study demonstrates that FA and AD have the potential to be sensitive biomarkers of the full extent of cord injury and might be useful in detecting remote injuries to the SC and in guiding new treatments.
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- 2019
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34. Application of Color Transformation Techniques in Pediatric Spinal Cord MR Images: Typically Developing and Spinal Cord Injury Population.
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Alizadeh M, Shah P, Conklin CJ, Middleton DM, Saksena S, Flanders AE, Krisa L, Mulcahey MJ, Faro SH, and Mohamed FB
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- Adolescent, Case-Control Studies, Child, Color, Female, Humans, Injury Severity Score, Male, Quality Control, Reference Values, Signal-To-Noise Ratio, Cervical Vertebrae injuries, Magnetic Resonance Imaging methods, Radiographic Image Enhancement methods, Spinal Cord Injuries diagnostic imaging
- Abstract
The purpose of this study was to evaluate an improved and reliable visualization method for pediatric spinal cord MR images in healthy subjects and patients with spinal cord injury (SCI). A total of 15 pediatric volunteers (10 healthy subjects and 5 subjects with cervical SCI) with a mean age of 11.41 years (range 8-16 years) were recruited and scanned using a 3.0T Siemens Verio MR scanner. T2-weighted axial images were acquired covering entire cervical spinal cord level C1 to C7. These gray-scale images were then converted to color images by using five different techniques including hue-saturation-value (HSV), rainbow, red-green-blue (RGB), and two enhanced RGB techniques using automated contrast stretching and intensity inhomogeneity correction. Performance of these techniques was scored visually by two neuroradiologists within three selected cervical spinal cord intervertebral disk levels (C2-C3, C4-C5, and C6-C7) and quantified using signal to noise ratio (SNR) and contrast to noise ratio (CNR). Qualitative and quantitative evaluation of the color images shows consistent improvement across all the healthy and SCI subjects over conventional gray-scale T2-weighted gradient echo (GRE) images. Inter-observer reliability test showed moderate to strong intra-class correlation (ICC) coefficients in the proposed techniques (ICC > 0.73). The results suggest that the color images could be used for quantification and enhanced visualization of the spinal cord structures in addition to the conventional gray-scale images. This would immensely help towards improved delineation of the gray/white and CSF structures and further aid towards accurate manual or automatic drawings of region of interests (ROIs).
- Published
- 2018
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35. Translational Challenges of Rat Models of Upper Extremity Dysfunction After Spinal Cord Injury.
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Krisa L, Runyen M, and Detloff MR
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- Animals, Disability Evaluation, Functional Laterality physiology, Rats, Translational Research, Biomedical, Disease Models, Animal, Recovery of Function physiology, Spinal Cord Injuries physiopathology, Upper Extremity physiopathology
- Abstract
There are approximately 17,500 new spinal cord injury (SCI) cases each year in the United States, with the majority of cases resulting from a traumatic injury. Damage to the spinal cord causes either temporary or permanent changes in sensorimotor function. Given that the majority of human SCIs occur in the cervical spinal level, the experimental animal models of forelimb dysfunction play a large role in the ability to translate basic science research to clinical application. However, the variation in the design of clinical and basic science studies of forelimb/upper extremity (UE) function prevents the ease of translation. This review provides an overview of experimental models of forelimb dysfunction used in SCI research with special emphasis on the rat model of SCI. The anatomical location and types of experimental cervical lesions, functional assessments, and rehabilitation strategies used in the basic science laboratory are reviewed. Finally, we discuss the challenges of translating animal models of forelimb dysfunction to the clinical SCI human population., Competing Interests: Supported by grants from the Craig H. Neilsen Foundation (#457508 MRD) and the National Institutes of Health National Institute of Neurological Disorders and Stroke (#NS97880 MRD). We certify that no party having a direct interest in the results of the research supporting this article has or will confer a benefit on us or on any organization with which we are associated and, if applicable, we certify that all financial and material support for this research (eg, NIH or NHS grants) and work are clearly identified.
- Published
- 2018
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36. Considerations and recommendations for selection and utilization of upper extremity clinical outcome assessments in human spinal cord injury trials.
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Jones LAT, Bryden A, Wheeler TL, Tansey KE, Anderson KD, Beattie MS, Blight A, Curt A, Field-Fote E, Guest JD, Hseih J, Jakeman LB, Kalsi-Ryan S, Krisa L, Lammertse DP, Leiby B, Marino R, Schwab JM, Scivoletto G, Tulsky DS, Wirth E, Zariffa J, Kleitman N, Mulcahey MJ, and Steeves JD
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- Humans, Clinical Trials as Topic methods, Outcome Assessment, Health Care methods, Spinal Cord Injuries diagnosis, Spinal Cord Injuries therapy
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Study Design: This is a focused review article., Objectives: This review presents important features of clinical outcomes assessments (COAs) in human spinal cord injury research. Considerations for COAs by trial phase and International Classification of Functioning, Disability and Health are presented as well as strengths and recommendations for upper extremity COAs for research. Clinical trial tools and designs to address recruitment challenges are identified., Methods: The methods include a summary of topics discussed during a two-day workshop, conceptual discussion of upper extremity COAs and additional focused literature review., Results: COAs must be appropriate to trial phase and particularly in mid-late-phase trials, should reflect recovery vs. compensation, as well as being clinically meaningful. The impact and extent of upper vs. lower motoneuron disease should be considered, as this may affect how an individual may respond to a given therapeutic. For trials with broad inclusion criteria, the content of COAs should cover all severities and levels of SCI. Specific measures to assess upper extremity function as well as more comprehensive COAs are under development. In addition to appropriate use of COAs, methods to increase recruitment, such as adaptive trial designs and prognostic modeling to prospectively stratify heterogeneous populations into appropriate cohorts should be considered., Conclusions: With an increasing number of clinical trials focusing on improving upper extremity function, it is essential to consider a range of factors when choosing a COA., Sponsors: Craig H. Neilsen Foundation, Spinal Cord Outcomes Partnership Endeavor.
- Published
- 2018
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37. Characterization of spinal cord diffusion tensor imaging metrics in clinically asymptomatic pediatric subjects with incidental congenital lesions.
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Saksena S, Alizadeh M, Middleton DM, Conklin CJ, Krisa L, Flanders A, Mulcahey MJ, Mohamed FB, and Faro SH
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Study Design: Retrospective study., Objectives: To perform quantitative DTI measurements of the entire cervical and thoracic spinal cord (SC) in typically developing (TD) pediatric subjects with incidental findings of syringomyelia or hydromyelia on conventional MRI and in a TD population without any abnormalities., Setting: USA., Methods: 26 TD recruited as part of large SC DTI study, four of these had incidental findings. Axial DTI images were acquired on 3T MR scanner to cover the cervical and thoracic SC. We performed group analysis of DTI values in the cord above and below the MR-defined lesion. For single-subject analysis, the cord above and below the lesion was compared to average values of TD population. A standard least squares regression model was used to compare DTI parameters fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) between TD population and subjects with hydromyelia and syringomyelia. A p value of 0.05 was used for statistical significance., Results: In group analysis, MD and AD were significantly different in cord above the lesion in subjects with hydromyelia and syringomyelia ( n = 4) compared to TD population ( n = 22). For single-subject analysis, DTI parameters were significantly different in cord above the syringomyelia and below the syringomyelia; MD, AD, and RD were significantly different. A subject with hydromyelia showed significant difference in FA below the lesion., Conclusions: This study demonstrates that DTI has the potential to be used as an imaging biomarker to evaluate SC above and below the congenital lesion in syringohydromyelia subjects., Competing Interests: Compliance with ethical standardsThe authors declare that they have no conflict of interest.
- Published
- 2018
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38. Identification of ghost artifact using texture analysis in pediatric spinal cord diffusion tensor images.
- Author
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Alizadeh M, Conklin CJ, Middleton DM, Shah P, Saksena S, Krisa L, Finsterbusch J, Faro SH, Mulcahey MJ, and Mohamed FB
- Subjects
- Child, False Positive Reactions, Female, Fuzzy Logic, Healthy Volunteers, Humans, Male, Normal Distribution, Reproducibility of Results, Sensitivity and Specificity, Spinal Cord pathology, Spinal Cord Injuries pathology, Artifacts, Diffusion Tensor Imaging, Spinal Cord diagnostic imaging, Spinal Cord Injuries diagnostic imaging
- Abstract
Purpose: Ghost artifacts are a major contributor to degradation of spinal cord diffusion tensor images. A multi-stage post-processing pipeline was designed, implemented and validated to automatically remove ghost artifacts arising from reduced field of view diffusion tensor imaging (DTI) of the pediatric spinal cord., Method: A total of 12 pediatric subjects including 7 healthy subjects (mean age=11.34years) with no evidence of spinal cord injury or pathology and 5 patients (mean age=10.96years) with cervical spinal cord injury were studied. Ghost/true cords, labeled as region of interests (ROIs), in non-diffusion weighted b0 images were segmented automatically using mathematical morphological processing. Initially, 21 texture features were extracted from each segmented ROI including 5 first-order features based on the histogram of the image (mean, variance, skewness, kurtosis and entropy) and 16s-order feature vector elements, incorporating four statistical measures (contrast, correlation, homogeneity and energy) calculated from co-occurrence matrices in directions of 0°, 45°, 90° and 135°. Next, ten features with a high value of mutual information (MI) relative to the pre-defined target class and within the features were selected as final features which were input to a trained classifier (adaptive neuro-fuzzy interface system) to separate the true cord from the ghost cord., Results: The implemented pipeline was successfully able to separate the ghost artifacts from true cord structures. The results obtained from the classifier showed a sensitivity of 91%, specificity of 79%, and accuracy of 84% in separating the true cord from ghost artifacts., Conclusion: The results show that the proposed method is promising for the automatic detection of ghost cords present in DTI images of the spinal cord. This step is crucial towards development of accurate, automatic DTI spinal cord post processing pipelines., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
39. Age related diffusion and tractography changes in typically developing pediatric cervical and thoracic spinal cord.
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Alizadeh M, Fisher J, Saksena S, Sultan Y, Conklin CJ, Middleton DM, Krisa L, Finsterbusch J, Flanders AE, Faro SH, Mulcahey MJ, and Mohamed FB
- Subjects
- Adolescent, Age Factors, Anisotropy, Child, Diffusion Magnetic Resonance Imaging methods, Female, Humans, Male, Spinal Cord growth & development, Spinal Cord Injuries, Diffusion Tensor Imaging methods, Image Processing, Computer-Assisted methods, Spinal Cord physiopathology, White Matter physiopathology
- Abstract
Background and Objective: Diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) are two techniques that can measure white matter integrity of the spinal cord. Recently, DTI indices have been shown to change with age. The purpose of this study is (a) to evaluate the maturational states of the entire pediatric spinal cord using DTI and DTT indices including fractional anisotropy (FA), mean diffusivity (MD), mean length of white matter fiber tracts and tract density and (b) to analyze the DTI and DTT parameters along the entire spinal cord as a function of spinal cord levels and age., Method: A total of 23 typically developing (TD) pediatric subjects ranging in age from 6 to 16 years old (11.94 ± 3.26 (mean ± standard deviation), 13 females and 10 males) were recruited, and scanned using 3.0 T MR scanner. Reduced FOV diffusion tensor images were acquired axially in the same anatomical location prescribed for the T2-weighted images to cover the entire spinal cord (C1-mid L1 levels). To mitigate motion induced artifacts, diffusion directional images were aligned with the reference image (b0) using a rigid body registration algorithm performed by in-house software developed in Matlab (MathWorks, Natick, Massachusetts). Diffusion tensor maps (FA and MD) and streamline deterministic tractography were then generated from the motion corrected DTI dataset. DTI and DTT parameters were calculated by using ROIs drawn to encapsulate the whole cord along the entire spinal cord by an independent board certified neuroradiologist. These indices then were compared between two age groups (age group A = 6-11 years ( n = 11) and age group B = 12-16 years ( n = 12)) based on similar standards and age definitions used for reporting spinal cord injury in the pediatric population. Standard least squared linear regression based on a restricted maximum likelihood (REML) method was used to evaluate the relationship between age and DTI and DTT parameters., Results: An increase in FA (group A = 0.42 ± 0.097, group B = 0.49 ± 0.116), white matter tract density (group A = 368.01 ± 236.88, group B = 440.13 ± 245.24) and mean length of fiber tracts (group A = 48.16 ± 20.48 mm, group B = 60.28 ± 23.87 mm) and a decrease in MD (group A = 1.06 ± 0.23 × 10
-3 mm2 /s, group B = 0.82 ± 0.24 × 10-3 mm2 /s) were observed with age along the entire spinal cord. Statistically significant increases have been shown in FA ( p = 0.004, R2 = 0.57), tract density ( p = 0.0004, R2 = 0.58), mean length of fiber tracts ( p < 0.001, R2 = 0.5) and a significant decrease has been shown in MD ( p = 0.002, R2 = 0.59) between group A and group B. Also, it has been shown DTI and DTT parameters vary along the spinal cord as a function of intervertebral disk and mid-vertebral body level., Conclusion: This study provides an initial understanding of age related changes of DTI values as well as DTT metrics of the spinal cord. The results show significant differences in DTI and DTT parameters which may result from decreasing water content, myelination of fiber tracts, and the thickening diameter of fiber tracts during the maturation process. Consequently, when quantitative DTI and DTT of the spinal cord is undertaken in the pediatric population an age and level matched normative dataset should be used to accurately interpret the quantitative results.- Published
- 2018
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40. Reduced Field of View Diffusion Tensor Imaging and Fiber Tractography of the Pediatric Cervical and Thoracic Spinal Cord Injury.
- Author
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Alizadeh M, Fisher J, Saksena S, Sultan Y, Conklin CJ, Middleton DM, Finsterbusch J, Krisa L, Flanders AE, Faro SH, Mulcahey MJ, and Mohamed FB
- Subjects
- Adolescent, Cervical Cord diagnostic imaging, Cervical Cord injuries, Child, Female, Humans, Image Interpretation, Computer-Assisted methods, Male, Spinal Cord diagnostic imaging, Diffusion Tensor Imaging methods, Neuroimaging methods, Spinal Cord Injuries diagnostic imaging
- Abstract
The aim of this study is to assess the utility and effectiveness of diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) of the entire pediatric cervical and thoracic spinal cord toward discrimination of typically developing (TD) controls and subjects with spinal cord injury (SCI). A total of 43 pediatric subjects, including 23 TD subjects ranging in age from 6 to 16 years old and 20 subjects with SCI ranging in age from 7 to 16 years, were recruited and scanned using a 3.0 Tesla magnetic resonance scanner. Reduced field of view diffusion tensor images were acquired axially to cover the entire spinal cord across two slabs. For DTI analysis, motion correction was performed by coregistration of the diffusion-weighted images to the reference image (b0). Streamline deterministic tractography results were generated from the preprocessed data. DTI and DTT parameters of the whole cord, including fractional anisotropy (FA), mean diffusivity (MD), tract length, and tract density, were calculated, averaged across the whole spinal cord, and compared between the TD and SCI groups. Statistically significant decreases have been shown in FA (TD = 0.46 ± 0.11; SCI = 0.37 ± 0.09; p < 0.0001) and tract density (TD = 405.93 ± 243.84; SCI = 268.90 ± 270.34; p < 0.0001). However, the mean length of tracts and MD did not show significant differences. When investigating differences in DTI and DTT parameters above and below the injury site, it was shown that the FA and tract density in patients with cervical SCI decreased significantly in the thoracic region. An identical trend was observed in the cervical region for patients with thoracic SCI as well. When comparing TD and SCI subjects, FA and tract density were the most sensitive parameters in detecting functional changes of the spinal cord in chronic pediatric SCI. The results show that both DTI and DTT have the potential to be imaging biomarkers in the diagnosis of SCI.
- Published
- 2018
- Full Text
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41. Use of ambulatory blood pressure monitoring in adolescents with SCI: a case series.
- Author
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Krisa L, Vogel LC, and Wecht JM
- Abstract
Introduction: Due the impact of maturation on cardiovascular hemodynamics the degree of cardiovascular dysfunction, attributable to spinal cord injury (SCI), in the pediatric and adolescent population remains unclear. While few studies have begun to assess this, there is still a void in the literature regarding the prevalence of cardiovascular dysfunction and how best to identify and treat it in this population., Case Presentation: The purpose of this case series is to present the cardiovascular profile of three adolescent patients with chronic SCI, ages 14-16, following 2 or 3 days of 24-h Ambulatory Blood Pressure Monitoring (ABPM)., Discussion: We found that there are variations across the different cases in most cardiovascular hemodynamic categories and a clarification of the International Standards to document remaining Autonomic Function after Spinal Cord Injury (ISAFSCI) may be needed to accurately identify the remaining autonomic cardiovascular function in the adolescent SCI population., Competing Interests: Compliance with ethical standardsThe authors declare that they have no competing interests.
- Published
- 2017
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42. Diffusion Tensor Imaging of the Normal Cervical and Thoracic Pediatric Spinal Cord.
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Saksena S, Middleton DM, Krisa L, Shah P, Faro SH, Sinko R, Gaughan J, Finsterbusch J, Mulcahey MJ, and Mohamed FB
- Abstract
Background and Purpose: DTI data of the normal healthy spinal cord in children are limited compared with adults and are typically focused on the cervical spinal cord. The purpose of this study was the following: to investigate the feasibility of obtaining repeatable DTI parameters along the entire cervical and thoracic spinal cord as a function of age in typically developing pediatric subjects; to analyze the DTI parameters among different transverse levels of the cervical and thoracic spinal cord; and to examine the sex differences in DTI parameters along the cervical and thoracic spinal cord., Materials and Methods: Twenty-two subjects underwent 2 identical scans by using a 3T MR imaging scanner. Axial diffusion tensor images were acquired by using 2 overlapping slabs to cover the cervical and thoracic spinal cord. After postprocessing, DTI parameters were calculated by using ROIs drawn on the whole cord along the entire spinal cord for both scans., Results: An increase in fractional anisotropy and a decrease in mean diffusivity, axial diffusivity, and radial diffusivity were observed with age along the entire spinal cord. Significantly lower fractional anisotropy and higher mean diffusivity values were observed in the lower cervical cord compared with the upper cervical cord. Axial diffusivity values in the cervical cord were higher compared with the thoracic cord. No statistically significant sex differences were observed for all DTI parameters. There was a moderate-to-strong repeatability for all DTI parameters., Conclusions: This study provides an initial understanding of DTI values of the spinal cord relevant to age and sex and shows that obtaining repeatable DTI values of the entire cord in children is feasible., (© 2016 by American Journal of Neuroradiology.)
- Published
- 2016
- Full Text
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43. Locomotor Training in the Pediatric Spinal Cord Injury Population: A Systematic Review of the Literature.
- Author
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Gorski K, Harbold K, Haverstick K, Schultz E, Shealy SE, and Krisa L
- Abstract
Background: The restoration of walking ability in the spinal cord injury (SCI) population is an increasingly important goal in physical therapy. Locomotor training (LT) is often implemented with the aim to restore ambulation. At this point, there are no guidelines for LT in the pediatric SCI population. Objectives: The aim of this review is to further narrow the effects of LT to the pediatric SCI population and develop recommendations for pediatric LT. Methods: A thorough search was performed using the following databases: Scopus, CINAHL, PubMed, and Ovid. Studies were selected based on the following inclusion criteria: pediatric SCI population, articles published within last 10 years, human subjects, and LT. Studies looking at other neurological disorders and subjects who were not previously ambulatory were excluded. Five students and one Faculty Research Advisor from the university's Doctor of Physical Therapy Program evaluated the inclusion criteria, conducted a risk of bias assessment using the Downs and Black checklist, and extracted the results. Results: Six studies were selected for this review. They showed gains in distance, gait speed, walking independence, and participation. There were variations in results when comparing gains in injury level based on the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI). Conclusions: Currently there is insufficient evidence to determine the best clinical practice guidelines for rehabilitation using LT within the pediatric SCI population.
- Published
- 2016
- Full Text
- View/download PDF
44. Spatially selective 2D RF inner field of view (iFOV) diffusion kurtosis imaging (DKI) of the pediatric spinal cord.
- Author
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Conklin CJ, Middleton DM, Alizadeh M, Finsterbusch J, Raunig DL, Faro SH, Shah P, Krisa L, Sinko R, Delalic JZ, Mulcahey MJ, and Mohamed FB
- Subjects
- Adolescent, Algorithms, Brain pathology, Brain physiopathology, Child, Female, Humans, Male, Spinal Cord Diseases physiopathology, Diffusion Magnetic Resonance Imaging methods, Diffusion Tensor Imaging methods, Image Processing, Computer-Assisted methods, Spinal Cord Diseases pathology
- Abstract
Magnetic resonance based diffusion imaging has been gaining more utility and clinical relevance over the past decade. Using conventional echo planar techniques, it is possible to acquire and characterize water diffusion within the central nervous system (CNS); namely in the form of Diffusion Weighted Imaging (DWI) and Diffusion Tensor Imaging (DTI). While each modality provides valuable clinical information in terms of the presence of diffusion and its directionality, both techniques are limited to assuming an ideal Gaussian distribution for water displacement with no intermolecular interactions. This assumption neglects pathological processes that are not Gaussian therefore reducing the amount of potentially clinically relevant information. Additions to the Gaussian distribution measured by the excess kurtosis, or peakedness, of the probabilistic model provide a better understanding of the underlying cellular structure. The objective of this work is to provide mathematical and experimental evidence that Diffusion Kurtosis Imaging (DKI) can offer additional information about the micromolecular environment of the pediatric spinal cord. This is accomplished by a more thorough characterization of the nature of random water displacement within the cord. A novel DKI imaging sequence based on a tilted 2D spatially selective radio frequency pulse providing reduced field of view (FOV) imaging was developed, implemented, and optimized on a 3 Tesla MRI scanner, and tested on pediatric subjects (healthy subjects: 15; patients with spinal cord injury (SCI):5). Software was developed and validated for post processing of the DKI images and estimation of the tensor parameters. The results show statistically significant differences in mean kurtosis (p < 0.01) and radial kurtosis (p < 0.01) between healthy subjects and subjects with SCI. DKI provides incremental and novel information over conventional diffusion acquisitions when coupled with higher order estimation algorithms.
- Published
- 2016
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45. The implications of injury in the developing nervous system on upper extremity function.
- Author
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Krisa L and Murray M
- Subjects
- Child, Preschool, Humans, Infant, Infant, Newborn, Trauma, Nervous System rehabilitation, Peripheral Nervous System growth & development, Pyramidal Tracts growth & development, Trauma, Nervous System complications, Trauma, Nervous System physiopathology, Upper Extremity physiology
- Abstract
Study Design: Literature review., Purpose: The corticospinal system (CS) and peripheral nervous system (PNS) are common sites of damage during the early stages of life. The prenatal or immediately prenatal period is the most common time for damage to occur. Here we briefly review the basic features of the development of the CS and the PNS and the clinical consequences of injury to or improper development of these systems on upper extremity (UE) function., Results: The proper development of both the CS and PNS is necessary to achieve adequate function of the (UE). Injury or improper development of these systems can lead to upper extremity dysfunction and limit participation in activities of daily living., Conclusions: Both the PNS and CS play major roles in the proper functioning of the UE. A better understanding of their roles and common developmental disorders is needed to move rehabilitation of motor impairments forward., (Copyright © 2015 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.)
- Published
- 2015
- Full Text
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46. Forelimb locomotor rating scale for behavioral assessment of recovery after unilateral cervical spinal cord injury in rats.
- Author
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Singh A, Krisa L, Frederick KL, Sandrow-Feinberg H, Balasubramanian S, Stackhouse SK, Murray M, and Shumsky JS
- Subjects
- Animals, Cervical Vertebrae, Disease Models, Animal, Female, Functional Laterality, Rats, Rats, Sprague-Dawley, Reproducibility of Results, Severity of Illness Index, Sex Factors, Spinal Cord pathology, Spinal Cord Injuries pathology, Time Factors, Disability Evaluation, Forelimb, Motor Activity, Recovery of Function, Spinal Cord Injuries diagnosis
- Abstract
Background: Cervical spinal cord injury (SCI) models in rats have become increasingly useful because of their translational potential. The goal of this study was to design, develop and validate a quick and reliable forelimb locomotor rating scale for adult rats with unilateral cervical SCI injury., New Method: Adult female rats were subjected to a C5 unilateral mild contusion (n=10), moderate contusion (n=10) or hemisection injury (n=9). Forelimb locomotion was evaluated before injury, four times during the first week (Days 2, 3, 4 and 7) and weekly for up to 8 weeks post-injury. Scoring categories were identified and animals were ranked based on their performance in these categories. The scale was validated for its usefulness by comparing animals with different injury models (dorsolateral funiculotomy C3/4), levels of injury (moderate contusion C4) and sex (male - moderate contusion C3/4) and also by correlating FLS scores with other established behavioral tests (grid walking and kinetic tests)., Results and Comparison With Existing Methods: Forelimb performance on both the grid-walking and kinetic tests was positively correlated with the forelimb locomotor rating scale (FLS). Histological analysis established a positive correlation between the spared tissue and the observed FLS score. Our results show that the new rating scale can reliably detect forelimb deficits and recovery predicted by other behavioral tests. Furthermore, the new method provides reproducible data between trained and naïve examiners., Conclusion: In summary, the proposed rating scale is a useful tool for assessment of injury and treatments designed to enhance recovery after unilateral cervical SCI., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
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47. Cerebral activation during the test of spinal cord injury severity in children: an FMRI methodological study.
- Author
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Krisa L, Middleton D, Faro S, Calhoun CL, Mohamed FB, and Mulcahey MJ
- Abstract
Background: The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) are internationally accepted to determine and classify the extent of motor and sensory impairment along with severity (ASIA Impairment Scale [AIS]) following spinal cord injury (SCI). The anorectal examination is a component of the ISNCSCI that determines injury severity. There is a void in the health care literature on the validity of the anorectal examination as an indication of SCI severity., Objective: To validate the use of functional magnetic resonance imagining (fMRI) for the purpose of classifying the severity of SCI in children., Methods: Seventeen patients, with the average age of 14.3 years, underwent 1 complete ISNCSCI examination. Subjects also underwent the anorectal portion of this exam while fMRI data were collected using a 3.0 Tesla Siemens Verio Scanner. Cortical areas of activation were analyzed for possible differences of cortical involvement between complete (AIS A) and incomplete (AIS B, C, and D) SCI subjects. Anxiety/anticipation of the test was also assessed., Results: This study established an fMRI imaging protocol that captures the cortical locations and intensity of activation during the test of sacral sparing. In addition to developing the data acquisition protocol, we also established the postacquisition preprocessing and statistical analysis parameters using SPM8., Conclusion: Preliminary findings indicate that fMRI is a useful tool in evaluating the validity of the anorectal examination in determining SCI severity. Assessment of which cortical regions are activated during the testing procedure provides an indication of which pathways are transmitting information to the brain.
- Published
- 2013
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48. Using a limited number of dermatomes as a predictor of the 56-dermatome test of the international standards for neurological classification of spinal cord injury in the pediatric population.
- Author
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Krisa L, Mulcahey MJ, Gaughan JP, Smith B, and Vogel LC
- Abstract
Background: For young children with spinal cord injury (SCI), the sensory exam of the International Standards for the Neurological Classification of Spinal Cord Injury (ISNCSCI) is long and arduous, often making it impossible to complete., Objectives: In this study, we determine whether an abbreviated sensory exam provides comparable information to the full 56-dermatome exam., Method: A total of 726 56-dermatome sensory exams were completed with 190 children and youth with SCI ranging in age from 3 to 21 years. The cohort was randomly split into test and validation groups. For the test group, a principal component analysis (PCA) was carried out separately for pin prick (PP) and light touch (LT) scores. From the PCA, a hierarchical cluster analysis was performed to identify the most influential set of 4, 8, 12, and 16 dermatomes. From the sensory exam data obtained from the validation group, a linear regression was performed to compare the limited-dermatome composite scores to the total 56-dermatome scores., Results: For both LT and PP, the 16-dermatome test resulted in the best fit (0.86 and 0.87, respectively) with the 56-dermatome test and was comprised of dermatomes from both the left (7 dermatomes) and right (9 dermatomes) sides and at least 1 dermatome from each vertebral region bilaterally (cervical, thoracic, lumbar, sacral)., Conclusion: A 16-dermatome sensory exam provided a good correlation to the 56-dermatome exam. The shortened exam may be useful for evaluating children with SCI who cannot tolerate the full examination.
- Published
- 2013
- Full Text
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49. Amphetamine-enhanced motor training after cervical contusion injury.
- Author
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Krisa L, Frederick KL, Canver JC, Stackhouse SK, Shumsky JS, and Murray M
- Subjects
- Animals, Biomechanical Phenomena drug effects, Cervical Vertebrae, Combined Modality Therapy, Housing, Animal, Motor Skills drug effects, Physical Therapy Modalities, Rats, Rats, Sprague-Dawley, Recovery of Function drug effects, Amphetamine administration & dosage, Central Nervous System Stimulants administration & dosage, Motor Activity drug effects, Spinal Cord Injuries drug therapy, Spinal Cord Injuries rehabilitation
- Abstract
Individually, motor training, pharmacological interventions, and housing animals in an enriched environment (EE) following spinal cord injury (SCI) result in limited functional improvement but, when combined, may enhance motor function. Here, we tested amphetamine (AMPH)-enhanced skilled motor training following a unilateral C3-C4 contusion injury on the qualitative components of reaching and on skilled forelimb function, as assessed using single-pellet and staircase reaching tasks. Kinematic analysis evaluated the quality of the reach, and unskilled locomotor function was also tested. Animals receiving AMPH and skilled forelimb training performed better than operated control animals on qualitative reaching, but not on skilled reaching. Those that received the combination treatment and were housed in EE cages showed significantly less improvement in qualitative reaching and grasping. Kinematic analysis revealed a decrease in digit abduction during skilled reaching among all groups, with no differences among groups. Kinematics provided no evidence that improved function was related to improved quality of reach. There was no evidence of neuroprotection in the cervical spinal cord. The absence of evidence for kinematic improvement or neuroprotection suggested that AMPH-enhanced motor training is due primarily to supraspinal effects, an enhancement of attention during skilled motor training, or plasticity in supraspinal circuitry involved with motor control.
- Published
- 2012
- Full Text
- View/download PDF
50. Diffusion tensor imaging in pediatric transverse myelitis: a case study.
- Author
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Barakat N, Mulcahey MJ, Shah P, Samdani A, Krisa L, Faro S, and Mohamed FB
- Subjects
- Child, Gadolinium, Humans, Magnetic Resonance Imaging methods, Male, Myelitis, Transverse diagnosis, Reproducibility of Results, Diffusion Tensor Imaging methods, Myelitis, Transverse pathology
- Abstract
Transverse myelitis is diagnosed based on the presence of spinal cord inflammation and the absence of infection to the central nervous system. In support of these criteria, patients undergo lumbar puncture to determine Cerebrospinal Fluid (CSF) pleocytosis and un-enhanced or Gadolinium-enhanced spinal Magnetic Resonance Imaging (MRI). We present the case of an 11~year-old previously healthy male who underwent a series of lab tests and MRI scans before a definite diagnosis of transverse myelitis four years prior to this study. The patient still shows deficits at the C4 cord level according to International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) examination, however, his MRI results are negative, and his Diffusion Tensor Imaging (DTI) results are close to values reported in healthy subjects.
- Published
- 2012
- Full Text
- View/download PDF
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