Sensorimotor dysfunction in multiple sclerosis and column-specific magnetization transfer-imaging abnormalities in the spinal cord

• Published in: Brain (London, England : 1878) Vol. 132; no. 5; pp. 1200 - 1209
• Main Authors: Zackowski, Kathleen M., Smith, Seth A., Reich, Daniel S., Gordon-Lipkin, Eliza, Chodkowski, BettyAnn A., Sambandan, Divya R., Shteyman, Michael, Bastian, Amy J., van Zijl, Peter C., Calabresi, Peter A.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.05.2009; Oxford Publishing Limited (England)
• Subjects: Adult; Analysis of Variance; Ankle; Biological and medical sciences; Brain - pathology; Case-Control Studies; Cervical Vertebrae; corticospinal tract; dorsal column medial lemniscal tract; Female; Humans; Image Processing, Computer-Assisted; magnetic resonance imaging; Magnetic Resonance Imaging - methods; Male; Medical sciences; Middle Aged; Multiple Sclerosis - pathology; Multiple Sclerosis - physiopathology; Multiple sclerosis and variants. Guillain barré syndrome and other inflammatory polyneuropathies. Leukoencephalitis; Multiple Sclerosis, Chronic Progressive - pathology; Multiple Sclerosis, Chronic Progressive - physiopathology; Multiple Sclerosis, Relapsing-Remitting - pathology; Multiple Sclerosis, Relapsing-Remitting - physiopathology; Muscle Strength; Neurology; Original; Regression Analysis; sensation; Sensation Disorders - pathology; Sensation Disorders - physiopathology; Sensory Thresholds; Spinal Cord - pathology; Spinal Cord - physiopathology; strength; Toes; Vibration; sensation; magnetic resonance imaging; strength; dorsal column medial lemniscal tract; corticospinal tract; Sensation; Dorsal column; Spinal cord; Nervous system diseases; Multiple sclerosis; Magnetization; Central nervous system; Nuclear magnetic resonance imaging; Inflammatory disease; Dysfunction; Central nervous system disease; Strength
• ISSN: 0006-8950; 1460-2156
• DOI: 10.1093/brain/awp032

The human spinal cord contains segregated sensory and motor pathways that have been difficult to quantify using conventional magnetic resonance imaging (MRI) techniques. Multiple sclerosis is characterized by both focal and spatially diffuse spinal cord lesions with heterogeneous pathologies that have limited attempts at linking MRI and behaviour. We used a novel magnetization-transfer-weighted imaging approach to quantify damage to spinal white matter columns and tested its association with sensorimotor impairment. We studied 42 participants with multiple sclerosis who each underwent MRI at 3 Tesla and quantitative tests of sensorimotor function. We measured cerebrospinal-fluid-normalized magnetization-transfer signals in the dorsal and lateral columns and grey matter of the cervical cord. We also measured brain lesion volume, cervical spinal cord lesion number and cross-sectional area, vibration sensation, strength, walking velocity and standing balance. We used linear regression to assess the relationship between sensorimotor impairment and MRI abnormalities. We found that the dorsal column cerebrospinal-fluid-normalized magnetization-transfer signal specifically correlated with vibration sensation (R = 0.58, P < 0.001) and the lateral column signal with strength (R = −0.45, P = 0.003). Spinal cord signal measures also correlated with walking and balance dysfunction. A stepwise multiple regression showed that the dorsal column signal and diagnosis subtype alone explained a significant portion of the variance in sensation (R2 = 0.54, P < 0.001), whereas the lateral column signal and diagnosis subtype explained a significant portion of the variance in strength (R2 = 0.30, P < 0.001). These results help to understand the anatomic basis of sensorimotor disability in multiple sclerosis and have implications for testing the effects of neuroprotective and reparative interventions.