Topographic Comparison of the Visual Function on Multifocal Visual Evoked Potentials with Optic Nerve Structure on Heidelberg Retinal Tomography

Purpose The authors’ objective was to compare the visual field obtained using multifocal visual evoked potential (mfVEP) testing with the optic nerve parameters of Heidelberg retinal tomography (HRT; Heidelberg Engineering, Heidelberg, Germany; software version 2.01) in primary open-angle glaucoma (POAG) patients and normal controls and to determine which parameters correlate with visual function. Design Cross-sectional study. Participants Eighty-one eyes of 42 adult POAG patients and normal controls between the ages of 40 and 80 years, of which 35 patients (67 eyes; mean age±standard deviation [SD], 68±10 years) had POAG, and 7 individuals who served as normal controls (14 eyes; mean age±SD, 61±10 years) were included. Methods A monocular mfVEP test, the AccuMap (Opera software version 2.0; ObjectiVision Pty. Ltd., Sydney, Australia), with a 58-sector pattern-reversal dart board array was recorded in both eyes per patient. These patients underwent the HRT 2 and mfVEP tests within 3 months of each other. Main Outcome Measures Amplitudes in the superior hemisphere of the mfVEP trace were compared with the HRT parameters in the inferior hemisphere of the HRT and vice versa using mixed effects regression models. Results Amplitudes on the superior hemisphere of the mfVEP recordings showed a significant direct correlation with rim-to-disc area ratio ( P = 0.0037), rim volume ( P = 0.0421), and mean retinal nerve fiber layer (RNFL) thickness ( P = 0.0016) and a significant inverse correlation with cup area ( P = 0.0009) and cup-to-disc area ratio ( P = 0.0037) in the inferior hemisphere of the HRT results. Amplitudes on the inferior hemisphere showed a significant direct correlation with rim-to-disc area ratio ( P = 0.036) and a significant inverse correlation with cup area ( P = 0.0007), cup-to-disc area ratio ( P = 0.036), cup volume ( P