Shahamat Tauhid
Brigham and Women's Hospital
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Featured researches published by Shahamat Tauhid.
Journal of Neuroimaging | 2011
James Stankiewicz; Bonnie I. Glanz; Brian C. Healy; Ashish Arora; Mohit Neema; Ralph H. B. Benedict; Zachary D. Guss; Shahamat Tauhid; Guy J. Buckle; Maria K. Houtchens; Samia J. Khoury; Howard L. Weiner; Charles R. G. Guttmann; Rohit Bakshi
To assess correlation between brain lesions and clinical status with 1.5T and 3T magnetic resonance imaging (MRI).
Journal of Neuroimaging | 2012
Adam B. Cohen; Mohit Neema; Ashish Arora; Elisa Dell’Oglio; Ralph H. B. Benedict; Shahamat Tauhid; Daniel Goldberg-Zimring; Christian D. Chavarro-Nieto; Antonella Ceccarelli; Joshua P. Klein; James Stankiewicz; Maria K. Houtchens; Guy J. Buckle; David C. Alsop; Charles R. G. Guttmann; Rohit Bakshi
To determine the interrelationships between MRI‐defined lesion and atrophy measures of spinal cord involvement and brain involvement and their relationships to disability in a small cohort of patients with multiple sclerosis (MS).
Multiple Sclerosis Journal | 2010
Antonia Ceccarelli; Maria A. Rocca; Mohit Neema; Vittorio Martinelli; Ashish Arora; Shahamat Tauhid; A. Ghezzi; Giancarlo Comi; Rohit Bakshi; Massimo Filippi
Gray matter (GM) magnetic resonance imaging (MRI) T2 hypointensity, a putative marker of iron deposition, is a frequent finding in patients with clinically definite (CD) multiple sclerosis (MS). The objective of this study was to assess: (a) how early deep GM T2 hypointensity occurs in MS, by studying patients with clinically isolated syndromes (CIS) suggestive of MS, and (b) whether they contribute to predict subsequent evolution to CDMS. Dual-echo scans using two different acquisition protocols were acquired from 47 CIS patients and 13 healthy controls (HC). Normalized T2-intensity of the basal ganglia and thalamus was quantified. Patients were assessed clinically at the time of MRI acquisition and after three years. During the observation period, 18 patients (38%) evolved to CDMS. At the baseline, only the GM T2-intensity of the left caudate nucleus was significantly reduced in CIS patients in comparison with the HC (p = 0.04). At the baseline, the T2 intensity of the left caudate nucleus was significantly lower (p = 0.01) in CIS patients with disease dissemination in space (DIS), but not in those without DIS, compared to the HC. The baseline T2 lesion volume, but not GM T2 hypointensity, was associated with evolution to CDMS (hazard ratio = 1.60, 95% confidence interval (CI) = 1.05—2.42; p = 0.02). In CIS patients, deep GM is not spared, suggesting that iron-related changes and neurodegeneration occurs early. The magnitude of such damage is only minor and not associated with an increased risk of evolution to CDMS.
American Journal of Neuroradiology | 2012
Antonia Ceccarelli; Jonathan S. Jackson; Shahamat Tauhid; Ashish Arora; J. Gorky; Elisa Dell'Oglio; A. Bakshi; Tanuja Chitnis; Samia J. Khoury; Howard L. Weiner; Charles R. G. Guttmann; Rohit Bakshi; Mohit Neema
BACKGROUND AND PURPOSE: VBM has been widely used to study GM atrophy in MS. MS lesions lead to segmentation and registration errors that may affect the reliability of VBM results. Improved segmentation and registration have been demonstrated by WM LI before segmentation. DARTEL appears to improve registration versus the USM. Our aim was to compare the performance of VBM-DARTEL versus VBM-USM and the effect of LI in the regional analysis of GM atrophy in MS. MATERIALS AND METHODS: 3T T1 MR imaging scans were acquired from 26 patients with RRMS and 28 age-matched NC. LI replaced WM lesions with normal-appearing WM intensities before image segmentation. VBM analysis was performed in SPM8 by using DARTEL and USM with and without LI, allowing the comparison of 4 VBM methods (DARTEL + LI, DARTEL − LI, USM + LI, and USM − LI). Accuracy of VBM was assessed by using NMI, CC, and a simulation analysis. RESULTS: Overall, DARTEL + LI yielded the most accurate GM maps among the 4 methods (highest NMI and CC, P < .001). DARTEL + LI showed significant GM loss in the bilateral thalami and caudate nuclei in patients with RRMS versus NC. The other 3 methods overestimated the number of regions of GM loss in RRMS versus NC. LI improved the accuracy of both VBM methods. Simulated data suggested the accuracy of the results provided from patient MR imaging analysis. CONCLUSIONS: We introduce a pipeline that shows promise in limiting segmentation and registration errors in VBM analysis in MS.
Journal of Neuroimaging | 2012
Brian C. Healy; Ashish Arora; Douglas L. Hayden; Antonia Ceccarelli; Shahamat Tauhid; Mohit Neema; Rohit Bakshi
To determine the proper method for the normalization of spinal cord volume.
American Journal of Neuroradiology | 2011
Joshua P. Klein; Ashish Arora; Mohit Neema; Brian C. Healy; Shahamat Tauhid; Daniel Goldberg-Zimring; Christian D. Chavarro-Nieto; James Stankiewicz; Adam B. Cohen; Guy J. Buckle; Maria K. Houtchens; Antonia Ceccarelli; Elisa Dell'Oglio; Charles R. G. Guttmann; David C. Alsop; David B. Hackney; Rohit Bakshi
BACKGROUND AND PURPOSE: Spinal cord atrophy is a common feature of MS. However, it is unknown which cord levels are most susceptible to atrophy. We performed whole cord imaging to identify the levels most susceptible to atrophy in patients with MS versus controls and also tested for differences among MS clinical phenotypes. MATERIALS AND METHODS: Thirty-five patients with MS (2 with CIS, 27 with RRMS, 2 with SPMS, and 4 with PPMS phenotypes) and 27 healthy controls underwent whole cord 3T MR imaging. The spinal cord contour was segmented and assigned to bins representing each C1 to T12 vertebral level. Volumes were normalized, and group comparisons were age-adjusted. RESULTS: There was a trend toward decreased spinal cord volume at the upper cervical levels in PPMS/SPMS versus controls. A trend toward increased spinal cord volume throughout the cervical and thoracic cord in RRMS/CIS versus controls reached statistical significance at the T10 vertebral level. A statistically significant decrease was found in spinal cord volume at the upper cervical levels in PPMS/SPMS versus RRMS/CIS. CONCLUSIONS: Opposing pathologic factors impact spinal cord volume measures in MS. Patients with PPMS demonstrated a trend toward upper cervical cord atrophy. However patients with RRMS showed a trend toward increased volume at the cervical and thoracic levels, which most likely reflects inflammation or edema-related cord expansion. With the disease causing both expansion and contraction of the cord, the specificity of spinal cord volume measures for neuroprotective therapeutic effect may be limited.
Journal of Neuroimaging | 2016
Renxin Chu; Shahamat Tauhid; Bonnie I. Glanz; Brian C. Healy; Gloria Kim; Vinit V. Oommen; Fariha Khalid; Mohit Neema; Rohit Bakshi
Whole brain atrophy is a putative outcome measure in monitoring relapsing‐remitting multiple sclerosis (RRMS). With the ongoing MRI transformation from 1.5T to 3T, there is an unmet need to calibrate this change. We evaluated brain parenchymal volumes (BPVs) from 1.5T versus 3T in MS and normal controls (NC).
Neuroreport | 2014
Rohit Bakshi; Mohit Neema; Shahamat Tauhid; Brian C. Healy; Bonnie I. Glanz; Gloria Kim; Jennifer Miller; Julia L. Berkowitz; Riley Bove; Maria K. Houtchens; Christopher Severson; James Stankiewicz; Lynn Stazzone; Tanuja Chitnis; Charles R. G. Guttmann; Howard L. Weiner; Antonia Ceccarelli
The objective of this study was to test a new version of the Magnetic Resonance Disease Severity Scale (MRDSS2), incorporating cerebral gray matter (GM) and spinal cord involvement from 3 T MRI, in modeling the relationship between MRI and physical disability or cognitive status in multiple sclerosis (MS). Fifty-five MS patients and 30 normal controls underwent high-resolution 3 T MRI. The patients had an Expanded Disability Status Scale score of 1.6±1.7 (mean±SD). The cerebral normalized GM fraction (GMF), the T2 lesion volume (T2LV), and the ratio of T1 hypointense LV to T2LV (T1/T2) were derived from brain images. Upper cervical spinal cord area (UCCA) was obtained from spinal cord images. A within-subject d-score (difference of MS from normal control) for each MRI component was calculated, equally weighted, and summed to form MRDSS2. With regard to the relationship between physical disability and MRDSS2 or its individual components, MRI–Expanded Disability Status Scale correlations were significant for MRDSS2 (r=0.33, P=0.013) and UCCA (r=−0.33, P=0.015), but not for GMF (P=0.198), T2LV (P=0.707), and T1/T2 (P=0.240). The inclusion of UCCA appeared to drive this MRI–disability relationship in MRDSS2. With regard to cognition, MRDSS2 showed a larger effect size (P=0.035) than its individual components [GMF (P=0.081), T2LV (P=0. 179), T1/T2 (P=0.043), and UCCA (P=0.818)] in comparing cognitively impaired with cognitively preserved patients (defined by the Minimal Assessment of Cognitive Function in MS). Both cerebral lesions (T1/T2) and atrophy (GMF) appeared to drive this relationship. We describe a new version of the MRDSS, which has been expanded to include cerebral GM and spinal cord involvement. MRDSS2 has concurrent validity with clinical status.
Journal of the Neurological Sciences | 2014
Shahamat Tauhid; Mohit Neema; Brian C. Healy; Howard L. Weiner; Rohit Bakshi
BACKGROUND While disease categories (i.e. clinical phenotypes) of multiple sclerosis (MS) are established, there remains MRI heterogeneity among patients within those definitions. MRI-defined lesions and atrophy show only moderate inter-correlations, suggesting that they represent partly different processes in MS. We assessed the ability of MRI-based categorization of cerebral lesions and atrophy in individual patients to identify distinct phenotypes. METHODS We studied 175 patients with MS [age (mean ± SD) 42.7 ± 9.1 years, 124 (71%) women, Expanded Disability Status (EDSS) score 2.5 ± 2.3, n = 18 (10%) clinically isolated demyelinating syndrome (CIS), n=115 (66%) relapsing-remitting (RR), and n = 42 (24%) secondary progressive (SP)]. Brain MRI measures included T2 hyperintense lesion volume (T2LV) and brain parenchymal fraction (to assess whole brain atrophy). Medians were used to create bins for each parameter, with patients assigned a low or high severity score. RESULTS Four MRI phenotype categories emerged: Type I = low T2LV/mild atrophy [n = 67 (38%); CIS = 14, RR = 47, SP = 6]; Type II = high T2LV/mild atrophy [n = 21 (12%); RR = 19, SP = 2]; Type III = low T2LV/high atrophy [n = 21 (12%); CIS = 4, RR = 16, SP = 1]; and Type IV = high T2LV/high atrophy [n = 66 (38%); RR = 33, S P = 33]. Type IV was the most disabled and was the only group showing a correlation between T2LV vs. BPF and MRI vs. EDSS score (all p < 0.05). CONCLUSIONS We described MRI-categorization based on the relationship between lesions and atrophy in individual patients to identify four phenotypes in MS. Most patients have congruent extremes related to the degree of lesions and atrophy. However, many have a dissociation. Longitudinal studies will help define the stability of these patterns and their role in risk stratification.
Neuroimmunology and Neuroinflammation | 2016
Rohit Bakshi; Ada Yeste; Bonny Patel; Shahamat Tauhid; Subhash Tummala; Roya Rahbari; Renxin Chu; Keren Regev; Pia Kivisäkk; Howard L. Weiner; Francisco J. Quintana
Objective: To determine whether peripheral immune responses as measured by serum antigen arrays are linked to cerebral MRI measures of disease severity in multiple sclerosis (MS). Methods: In this cross-sectional study, serum samples were obtained from patients with relapsing-remitting MS (n = 21) and assayed using antigen arrays that contained 420 antigens including CNS-related autoantigens, lipids, and heat shock proteins. Normalized compartment-specific global brain volumes were obtained from 3-tesla MRI as surrogates of atrophy, including gray matter fraction (GMF), white matter fraction (WMF), and total brain parenchymal fraction (BPF). Total brain T2 hyperintense lesion volume (T2LV) was quantified from fluid-attenuated inversion recovery images. Results: We found serum antibody patterns uniquely correlated with BPF, GMF, WMF, and T2LV. Furthermore, we identified immune signatures linked to MRI markers of neurodegeneration (BPF, GMF, WMF) that differentiated those linked to T2LV. Each MRI measure was correlated with a specific set of antibodies. Strikingly, immunoglobulin G (IgG) antibodies to lipids were linked to brain MRI measures. Based on the association between IgG antibody reactivity and each unique MRI measure, we developed a lipid index. This comprised the reactivity directed against all of the lipids associated with each specific MRI measure. We validated these findings in an additional independent set of patients with MS (n = 14) and detected a similar trend for the correlations between BPF, GMF, and T2LV vs their respective lipid indexes. Conclusions: We propose serum antibody repertoires that are associated with MRI measures of cerebral MS involvement. Such antibodies may serve as biomarkers for monitoring disease pathology and progression.