Thalamic lesions in multiple sclerosis by 7T MRI: Clinical implications and relationship to cortical pathology

Abstract

Objective Pathology in both cortex and deep gray matter contribute to disability in multiple sclerosis (MS). We used the increased signal-to-noise ratio of 7-tesla (7T) MRI to visualize small lesions within the thalamus and to relate this to clinical information and cortical lesions. Methods 7T MRI scans were obtained on 34 MS cases and 15 healthy volunteers. Thalamic lesion number and volume were related to demographic data, clinical disability measures, and lesions in cortical gray matter. Results Thalamic lesions were found in 24/34 of MS cases. Two lesion subtypes were noted: discrete, ovoid lesions, and more diffuse lesional areas lining the periventricular surface. The number of thalamic lesions was greater in progressive MS compared to relapsing remitting (mean ± SD, 10.7 ± 0.7 vs. 3.0 ± 0.7, respectively, p < 0.001). Thalamic lesion burden (count and volume) correlated with EDSS score and measures of cortical lesion burden, but not with white matter lesion burden or white matter volume. Conclusions 7T MRI allows identification of thalamic lesions in MS, which are associated with disability, progressive disease, and cortical lesions. Thalamic lesion analysis may be a simpler, more rapid estimate of overall gray matter lesion burden in MS.

Structural correlates for fatigue in early relapsing remitting multiple sclerosis

“…The significant decrease in FA and increase in MD within the thalamus in MSF seem not be attributable to typical MS lesions, which, in line with our results, have been recently reported not to occur frequently in RRMS patients in this region [29]. These results are also in agreement with the VBM analysis.…”

Gray matter damage in multiple sclerosis: Impact on clinical symptoms

“…In-vivo research of lesions in other GM structures in relation to symptom development is sparse. A recent study with 7 T MRI, found thalamic lesions in 24 of 34 MS patients and thalamic lesion load correlated with EDSS and the 9HPT (Harrison et al, 2015).…”

Increased multiple sclerosis relapses related to lower prevalence of pain

“…Furthermore, with the advent of more powerful MRI scans, the confirmation of involvement of the gray matter became more sensitive. Harrison et al 25 conducted a study with 34 patients and demonstrated through 7-Tesla MRI scan that thalamic lesions were present in 24 patients. It is known that such lesions are associated with a higher EDSS score, cortical lesions and progressive forms.…”