ALTERAZIONI DEL RIFLESSO PUPILLARE ALLA LUCE NEI PAZIENTI CON SCLEROSI MULTIPLA

In this study we evaluated Pupillary Light Reflex (PLR), Visual Evoked Potentials (VEPs) and brain Magnetic Resonance Imaging (MRI) in 20 Multiple Sclerosis (MS) patients. We considered the amplitudes and latencies of direct and indirect PLRs, the constriction and redilatation velocity and the time to reach the maximum pupillary constriction. Thirty percent of MS patients had PLR latencies above the normal range. Mean latencies, amplitudes and pupillary constriction velocity of both and indirect PLRs were prolonged in MS patients when compared to normal controls. Abnormal VEPs were found in 60 percent of patients while 40 percent of patients had areas of increased signal in the midbrain. Statistically significant correlations were found between PLR latencies and P100 or N70 VEPs components (p <0.002 and p <0.0001 respectively). No relationship were established between PLR latencies and previous history of optic neuritis, decreased visual acuity or midbrain MRI findings. Our preliminary results suggest that PLR abnormalities mainly reflect the impairment of afferent pupillary pathway.