RESUMO
PURPOSE: To investigate the clinical potential of multifocal electroretinography (mf-ERG) for the evaluation of residual retinal function in retinitis pigmentosa (RP). METHODS: From a group of 41 patients with RP examined for full-field and mf-ERGs, 24 patients were selected in whom the full-field ERGs were non-detectable. Data from the mf-ERGs of this group were reviewed retrospectively. Patients were divided into two groups based on best corrected visual acuity (BCVA); Group A, with a BCVA of less than 0.5, and group B with a BCVA greater than 0.5. The amplitudes and implicit times of Ring 1 and Ring 2 among six concentric rings were measured for comparison between mf-ERG groups. RESULTS: In the mf-ERGs, the amplitudes of Ring 1 and Ring 2 were reduced and implicit time was delayed in all 48 eyes of 24 patients in whom scotopic and photopic responses were non-detectable in full-field ERGs, whereas, there were no detectable responses in Rings 3 thru 6. There was a greater reduction in amplitude and an increased delay in implicit time in group A. CONCLUSIONS: The mf-ERG can estimate the residual macular function in a group of patients with RP in whom the full-field ERG is non-recordable.