Application of multifocal visual evoked potentials in the assessment of visual dysfunction in macular diseases

Purpose To evaluate the use of AccuMap multifocal visual evoked potentials (mfVEP) in visual dysfunction caused by macular diseases. Methods Forty-eight eyes with known macular diseases underwent AccuMap mfVEP and microperimetry 1 (MP1) assessments. Evaluation of mfVEP abnormality was based on an amplitude deviation probability plot and the AccuMap Severity Index (ASI). Correlation analyses of the mean mfVEP amplitude corresponding to a radius of 2 degrees, 5 degrees, and 10 degrees of the central visual field, minimum angle of resolution best-corrected visual acuity (BCVA), and MP1 mean sensitivity of the corresponding areas were performed. Results Among the 48 affected eyes, AccuMap mfVEP detected an abnormality of the central visual field in 45 eyes, with a sensitivity of 93.8%. The mean mfVEP amplitudes within a radius of 2 degrees, 5 degrees, and 10 degrees of the central visual field were found to be positively correlated with BCVA (P<0.01 for all groups). The mean amplitudes also positively correlated with the MP1 mean sensitivity value of the corresponding visual field (P<0.01 for all groups). In the group with stable fixation or predominantly central fixation, the mean mfVEP amplitudes did not correlate with the BCVA or the MP1 mean sensitivity value. Regardless of the fixation status, the ASI was found to correlate with both the BCVA and the total MP1 mean defect value. Conclusion Objective perimetry using AccuMap mfVEP might be applied in the assessment of macular function, with the ASI offering a potentially useful indicator for evaluating macular dysfunction. Eye (2011) 25, 1302-1309; doi:10.1038/eye.2011.153; published online 1 July 2011