Monocular blindness with preserved direct and consensual pupillary reflex in multiple sclerosis

F. Lhermitte, L. Guillaumat and O. Lyon-Caen

A 22-year-old woman with definite multiple sclerosis had right-eye blindness with preserved direct and consensual pupillary reflex to light. The anatomy of the fibers inside the optic nerve did not give a satisfactory explanation of this phenomenon. On the other hand, this case appeared to support the idea of biochemical differences between the myelin of visual pathways and that of reflex pathways. Studies are necessary to confirm this hypothesis.