Integrity of the Anterior Visual Pathway and Its Association with Ambulatory Performance in Multiple Sclerosis

Abstract

Background. Retinal nerve fiber layer thickness and total macular volume (TMV) represent markers of neuroaxonal degeneration within the anterior visual pathway that might correlate with ambulation in persons with multiple sclerosis (MS). Objective. This study examined the associations between and TMV with ambulatory parameters in MS. Methods. Fifty-eight MS patients underwent a neurological examination for generation of an expanded disability status scale (EDSS) score and measurement of and TMV using optical coherence tomography (OCT). Participants completed the 6-minute walk (6MW) and the timed 25-foot walk (T25FW). The associations were examined using generalized estimating equation models that accounted for within-patient, inter-eye correlations, and controlled for disease duration, EDSS score, and age. Results. was not significantly associated with 6MW or T25FW . TMV was significantly associated with 6MW and T25FW . The coefficients indicated that unit differences in 6MW (100 feet) and T25FW (1 second) were associated with 0.040 and −0.048 unit differences in TMV (mm3), respectively. Conclusion. Integrity of the anterior visual pathway, particularly TMV, might represent a noninvasive measure of neuroaxonal degeneration that is correlated with ambulatory function in MS.