Cervical Cord T1-weighted Hypointense Lesions at MR Imaging in Multiple Sclerosis: Relationship to Cord Atrophy and Disability.

Abstract

Purpose To characterize the spatial distribution of cervical cord T1-weighted hypointense lesions in patients with multiple sclerosis (MS) and analyze their association with cord atrophy and disability. Materials and Methods For this prospective study that took place between 2014 and 2016, 3.0-T high-resolution T1-weighted cervical cord magnetic resonance (MR) images and clinical evaluations were obtained from 82 patients with relapsing-remitting MS (RRMS), 33 patients with secondary progressive MS (SPMS), 25 patients with primary progressive MS (PPMS), and 35 sex-matched healthy control participants. Hypointense cord lesions on T1-weighted imaging were identified and corresponding lesion masks were produced. A semiautomatic method on the basis of active surfaces was used to perform voxel-wise assessment (by using statistical parametric mapping and full factorial models) of T1-weighted hypointense lesion distribution and cord atrophy. Results T1-weighted hypointense cervical cord lesions were detected in 122 of 140 (87.1%) patients with MS. Lesions were preferentially located in the posterior (P = .01) and upper (P < .001) cervical cord. Lesion extent at C1/C2 and C5 was higher in patient with SPMS versus RRMS, and patients with PPMS versus RRMS and SPMS (P value range, <.001 to .05). Cord atrophy at upper cervical levels was found in patients with MS compared with control participants, especially in progressive MS (P value range, <.001 to .04). Partial overlap (r = 0.66; P < .001) occurred between regions with T1-weighted hypointense cord lesions and atrophy. Cord atrophy (r value range, -0.24 to -0.48; P < .001) and T1-weighted hypointense cord lesion extent (r value range, 0.36-0.42; P < .001) were correlated with clinical disability. Conclusion Hypointense lesions at T1-weighted imaging were observed in the cervical spinal cord of the majority of patients with MS and more widespread in progressive than in relapsing MS phenotypes. Both T1-weighted hypointense cord lesions and atrophy correlated with patient clinical disability.