Electrophysiologic evaluation of retinal function in patients with psoriasis and vitiligo

To investigate the relation between psoriasis and vitiligo with the electrophysiologic function of the retinal photoreceptors.

Patients with psoriasis or vitiligo referred for PUVA therapy were enrolled. Complete eye examination was performed. Patients with any drug or familial history or abnormal eye examination that might affect the retinal function were excluded. Standardized full-field electroretinogram (ERG) elicited with Ganzfeld stimuli using the commercial ERG system (Retiport32; Roland Consult) according to International Society for Clinical Electrophysiology of Vision guidelines was performed. The outcome measures were the difference between the mean rod response, standard combined response, single-flash cone response and 30-Hz flicker wave amplitudes of the patients and normal population.

Seventy-six eyes of 38 patients (vitiligo: 21; psoriasis: 17) and 40 eyes of 20 normal subjects were enrolled in this study. The mean age of patients was 31.3 ± 11.3 years (range 16-54 years). Twenty-two patients (58 %) were female. The mean rod response b-wave, standard combined a- and b-waves, single-flash cone response b-wave and the 30-Hz flicker (N1-P1) amplitudes were significantly lower than the normal population in the same range of age as the study group. There was no significant difference between the patients with vitiligo and those with psoriasis in all wave amplitudes (P = 0.094).

This study showed that overall retinal electrophysiologic function in patients with vitiligo or psoriasis is significantly impaired compared with normal population, independent of age and sex.