-
[show abstract]
[hide abstract]
ABSTRACT: OBJECTIVE: This study assessed the tissue integrity of major cervical cord tracts by using diffusion tensor imaging (DTI) to determine the relationship with specific clinical functions carried by those tracts. METHODS: This was a cross-sectional study of 37 patients with multiple sclerosis or neuromyelitis optica with remote cervical cord disease. Finger vibratory thresholds, 25-foot timed walk (25FTW), 9-hole peg test (9HPT), and Expanded Disability Status Scale were determined. DTI covered cervical regions C1 through C6 with 17 5-mm slices (0.9 × 0.9 mm in-plane resolution). Regions of interest included posterior columns (PCs) and lateral corticospinal tracts (CSTs). Hierarchical linear mixed-effect modeling included covariates of disease subtype (multiple sclerosis vs neuromyelitis optica), disease duration, and sex. RESULTS: Vibration thresholds were associated with radial diffusivity (RD) and fractional anisotropy (FA) in the PCs (both p < 0.01), but not CSTs (RD, p = 0.29; FA, p = 0.14). RD and FA in PCs, and RD in CSTs were related to 9HPT (each p < 0.0001). 25FTW was associated with RD and FA in PCs (p < 0.0001) and RD in CSTs (p = 0.008). Expanded Disability Status Scale was related to RD and FA in PCs and CSTs (p < 0.0001). Moderate/severe impairments in 9HPT (p = 0.006) and 25FTW (p = 0.017) were more likely to show combined moderate/severe tissue injury within both PCs and CSTs by DTI. CONCLUSIONS: DTI can serve as an imaging biomarker of spinal cord tissue injury at the tract level. RD and FA demonstrate strong and consistent relationships with clinical outcomes, specific to the clinical modality.
Neurology 05/2013; · 8.31 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: CXCL13, a B-cell chemokine, has been proposed as a biomarker in a variety of conditions, some of which can mimic multiple sclerosis and can have very high levels. In this case-control study, cerebrospinal fluid (CSF) CXCL13 was elevated in multiple sclerosis, neuromyelitis optica and other inflammatory neurological controls compared with noninflammatory controls. Levels did not differentiate disease groups. For all subjects taken together, CSF CXCL13 correlated with CSF WBC, oligoclonal band numbers, CSF protein, EDSS, and neurofilament levels. In subgroup analyses, CSF CXCL13 correlated with CSF WBC in neuromyelitis optica and IgG index in multiple sclerosis. Additionally, serum CXCL13 was elevated in neuromyelitis optica.
Multiple Sclerosis 01/2013; · 4.26 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We describe a cardiac gated high in-plane resolution axial human cervical spinal cord diffusion tensor imaging (DTI) protocol. Multiple steps were taken to optimize both image acquisition and image processing. The former includes slice-by-slice cardiac triggering and individually tiltable slices. The latter includes (i) iterative 2D retrospective motion correction; (ii) image intensity outlier detection to minimize the influence of physiological noise; (iii) a non-linear DTI estimation procedure incorporating non-negative eigenvalue priors; (iv) tract-specific region-of-interest (ROI) identification based on an objective geometry reference. Using these strategies in combination, radial diffusivity (λ(⊥)) was reproducibly measured in white matter (WM) tracts (adjusted mean [95% confidence interval]=0.25 [0.22, 0.29] μm(2)/ms), lower than previously reported λ(⊥) values in the in vivo human spinal cord DTI literature. Radial diffusivity and fractional anisotropy (FA) measured in WM varied from rostral to caudal as did mean translational motion, likely reflecting respiratory motion effect. Given the considerable sensitivity of DTI measurements to motion artifact, we believe outlier detection is indispensable in spinal cord diffusion imaging. We also recommend using a mixed-effects model to account for systematic measurement bias depending on cord segment.
NeuroImage 11/2012; · 5.89 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: OBJECTIVE To contrast differences in pain and treatment outcomes between neuromyelitis optica (NMO) and multiple sclerosis (MS). DESIGN Retrospective, cross-sectional cohort study. SETTING Academic MS center. PATIENTS Complete ascertainment of an academic MS center cohort of NMO and an MS comparison sample cohort. MAIN OUTCOME MEASURES Current pain was quantified by a 10-point scale and the McGill Pain Questionnaire. Expanded Disability Status Scale score and number of involved spinal cord levels were collected in addition to testing for cognition, fatigue, depression, and quality of life. Number and types of pain medications were tabulated. RESULTS Current pain was more common in subjects with NMO (n = 29) vs MS (n = 66) (86.2% vs 40.9%; P < .001) and more severe on a 10-point scale (5.38 vs 1.85; P < .001). Pain remained more common after controlling for disability and number of spinal cord segments (P = .03). Prescription pain medication was used more frequently in subjects with NMO compared with subjects with MS (75.9% vs 37.8%; P < .001), often requiring more than 1 medication (65.5% vs 15.2%; P < .001). No subject with NMO taking pain medication (22 of 29) rated their current pain as 0 of 10, whereas almost half of those taking pain medication with MS were currently free of pain (0% vs 48%; P = .006). CONCLUSIONS Neuromyelitis optica is frequently associated with severe pain that appears insufficiently controlled by pharmacologic interventions. Future studies should evaluate the efficacy of a multidisciplinary and multimodal approach to pain management.
Archives of neurology 08/2012; · 6.31 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Multiple sclerosis (MS) and neuromyelitis optica (NMO) both affect spinal cord with notable differences in pathology.
Determine the utility of diffusion tensor imaging (DTI) to differentiate the spinal cord lesions of NMO from MS within and outside T2 lesions.
Subjects greater than or equal to 12 months from a clinical episode of transverse myelitis underwent a novel transaxial cervical spinal cord DTI sequence. Ten subjects with NMO, 10 with MS and 10 healthy controls were included.
Within T2 affected white matter regions, radial diffusivity was increased in both NMO and MS compared with healthy controls (p<0.001, respectively), and to a greater extent in NMO than MS (p<0.001). Axial diffusivity was decreased in T2 lesions in both NMO and MS compared with controls (p<0.001, p=0.001), but did not differ between the two diseases. Radial diffusivity and fractional anisotropy within white matter regions upstream and downstream of T2 lesions were different from controls in each disease.
Higher radial diffusivity within spinal cord white matter tracts derived from diffusion tensor imaging were appreciated in NMO compared with MS, consistent with the known greater tissue destruction seen in NMO. DTI also detected tissue alterations outside T2 lesions and may be a surrogate of anterograde and retrograde degeneration.
Multiple Sclerosis 02/2012; 18(9):1259-68. · 4.26 Impact Factor
-
Neurology 05/2011; 76(22):e106-9. · 8.31 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Correlation of diffusion tensor imaging (DTI) with histochemical staining for demyelination and axonal damage in multiple sclerosis (MS) ex vivo human cervical spinal cords.
In MS, demyelination, axonal degeneration, and inflammation contribute to disease pathogenesis to variable degrees. Based upon in vivo animal studies with acute injury and histopathologic correlation, we hypothesized that DTI can differentiate between axonal and myelin pathologies within humans.
DTI was performed at 4.7 T on 9 MS and 5 normal control fixed cervical spinal cord blocks following autopsy. Sections were then stained for Luxol fast blue (LFB), Bielschowsky silver, and hematoxylin and eosin (H&E). Regions of interest (ROIs) were graded semi-quantitatively as normal myelination, mild (<50%) demyelination, or moderate-severe (>50%) demyelination. Corresponding axonal counts were manually determined on Bielschowsky silver. ROIs were mapped to co-registered DTI parameter slices. DTI parameters evaluated included standard quantitative assessments of apparent diffusion coefficient (ADC), relative anisotropy (RA), axial diffusivity and radial diffusivity. Statistical correlations were made between histochemical gradings and DTI parameters using linear mixed models.
Within ROIs in MS subjects, increased radial diffusivity distinguished worsening severities of demyelination. Relative anisotropy was decreased in the setting of moderate-severe demyelination compared to normal areas and areas of mild demyelination. Radial diffusivity, ADC, and RA became increasingly altered within quartiles of worsening axonal counts. Axial diffusivity did not correlate with axonal density (p=0.091).
Increased radial diffusivity can serve as a surrogate for demyelination. However, radial diffusivity was also altered with axon injury, suggesting that this measure is not pathologically specific within chronic human MS tissue. We propose that radial diffusivity can serve as a marker of overall tissue integrity within chronic MS lesions. This study provides pathologic foundation for on-going in vivo DTI studies in MS.
NeuroImage 01/2011; 55(4):1454-60. · 5.89 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To describe the clinical and imaging characteristics of spinal cord ring enhancement in multiple sclerosis (MS).
Clinical case series.
Academic referral center.
Twenty patients with MS who had spinal cord ring enhancement were retrospectively identified from 322 cervical and thoracic spinal cord magnetic resonance imaging studies during a 3-year period.
Demographics, disability, and pattern of enhancement on spinal cord and concomitant brain magnetic resonance imaging results.
Ring enhancement was seen in 20 patients with spinal cord enhancement, most commonly in the cervical cord. Incomplete or "open" ring enhancement was the dominant pattern in 19 of the 20 patients (95%). Concurrent enhancing brain lesions were present in 14 patients, 8 of which (57%) exhibited a ring pattern of enhancement. At the time of imaging, the Expanded Disability Status Scale scores ranged from 1.0 to 7.0 (median score, 3.0).
Ring enhancement is not an uncommon pattern for spinal cord lesions in MS, occurring with a prevalence of 6.2% (20 of 322 imaging studies). The most common pattern is incomplete ring enhancement in the cervical spinal cord. Recognition of this pattern may improve and expedite the diagnosis of MS and preclude the need for invasive diagnostic interventions.
Archives of neurology 11/2010; 67(11):1395-8. · 6.31 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate antibodies to myelin oligodendrocyte glycoprotein (MOG) in the serum and cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS) and control individuals.
Prospective case-control series.
Academic referral center.
Twenty-six controls with noninflammatory neurologic disease and 35 patients with MS donated serum and CSF for recombinant MOG (rMOG) antibody determination.
Serum and CSF rMOG antibody and albumin levels were used to calculate an rMOG index. Clinical disability, CSF markers, and magnetic resonance metrics were correlated with the rMOG index.
The rMOG index was elevated in MS patients compared with controls (P = .01). Patients with progressive MS exhibited elevated rMOG indexes compared with patients with relapsing-remitting MS (P = .04). The rMOG index was inferior to the IgG index in differentiating MS patients from controls. However, 7 of 16 patients with MS who had normal immunoglobulin G indexes had an elevated rMOG index. The rMOG index did not correlate with clinical disability, other CSF markers, or radiographic outcome measures.
The rMOG index, a marker of intrathecal MOG antibody production, may provide complementary information to routine CSF testing in the diagnosis of MS. Furthermore, intrathecal anti-MOG antibody production may be more pronounced in progressive than in relapsing forms of MS.
Archives of neurology 09/2010; 67(9):1102-8. · 6.31 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A challenge for the clinician treating patients with multiple sclerosis (MS) is to determine the most effective treatment while weighing the benefits and risks. Results of the phase 2 and phase 3 studies on natalizumab were received with great interest, in part due to the "improved" risk reduction for relapse rate, disease progression, and MRI metrics observed in comparison to results in trials of beta-interferon and glatiramer acetate. However, comparison across trials is invalid, in large part due to differences in the study populations. The increased efficacy observed in more recent trials has also been attributed to a fundamental change in subjects with MS enrolled in recent trials compared with the prior decade. In this article, we debate the relative efficacy of natalizumab vs the older injectable therapies.
Neurology 09/2009; 73(12):984-90. · 8.31 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The role B cells and humoral immunity play in multiple sclerosis (MS) is continually evolving. Recent discoveries include advances in lesion classification, identification of B cell clonal expansion in the central nervous system with evidence of antigen targeting, identification of chemokines in MS lesions, and expansion of information on the roles of autoantibodies and complement. Strong indications are accumulating that a greater degree of humoral dysfunction may lead to worsened long-term prognosis in MS. Effects of established MS treatments on B cells and their products have been further defined. Treatments that specifically target B cells are being implemented and hold promise.
Current Neurology and Neuroscience Reports 06/2007; 7(3):231-8. · 3.45 Impact Factor