Pupillary response to sparse multifocal stimuli in multiple sclerosis patients

The objective of this paper is to investigate the pattern of abnormalities and establish the diagnostic power of multifocal objective pupil perimetry (mfPOP) in multiple sclerosis (MS). Methods: A prospective study enrolling 35 normal (47.9 ± 16.8 years, 22 females) and 85 MS subjects (49.8 ± 11.3 years, 62 females; 72 relapsing-remitting (RR), and 13 primary or secondary progressives (PorS)). EDSS scores for the RR and PorS groups were 3.53 ± 1.04 (mean ± SD), and 5.9 ± 1.43, respectively. mfPOP responses were obtained from 44 regions/visual field. Each region was analysed according to response time-to-peak and standardised amplitude (AmpStd). Predictive power was measured by percentage area under the receiver operator curve (%AUC). Results: mfPOP responses showed a significant reduction of 0.69 ± 0.04 dB (mean ± SE) in AmpStd and significantly delayed time-to-peak of 25.95 ± 0.89 ms (mean ± SE) in MS subjects compared to control subjects (p<0.001). %AUC was greater for time-to-peak than AmpStd both for RR and PorS patients. Diagnostic power followed the EDSS scores but not a history of optic neuritis.Conclusions: mfPOP is well tolerated and potentially has a role in the diagnosis and assessment of patients with MS.