Biplanar MRI for the assessment of the spinal cord in multiple sclerosis

Objective: To investigate the entire spinal cord (SC) of multiple sclerosis (MS) patients with biplanar MRI and to relate these MRI findings to clinical functional scores. Methods: Two hundred and two patients (140 women, 62 men 24-74 years, Expanded Disability Status Scale (EDSS) scores 0-7.5) were investigated clinically and with biplanar MRI. Sagittal and axial proton density weighted (PDw) and T2 weighted (T2w) images of the whole SC were obtained employing parallel imaging. Data were analyzed by consensus reading using a standardized reporting scheme. Different combinations of findings were compared to EDSS scores with Spearman's rank correlation coefficient (rho). Results: The combined analysis of sagittal and axial planes demonstrated slightly differing results in 97/202 (48%) patients. There were 9% additional lesions identified, leading to a higher lesion count in 28% of these patients, but also rejection of equivocal abnormality leading to a lower lesion count in 11% of patients. Considering both sagittal and axial images, SC abnormalities were found in 167/202 (83%) patients. When compared with EDSS scores, the combination of focal lesions, signs of atrophy and diffuse abnormalities showed a moderate correlation (rho=0.52), that precludes its use for individual patient assessment. Conclusion: Biplanar MRI facilitates a comprehensive identification, localization, and grading of pathological SC findings in MS patients. This improves the confidence and utility of SC imaging.