Multifocal Visual Evoked Potential for Evaluation of Open Angle Glaucoma Patients

Abstract

POAG is mostly asymptomatic until the late stage. The sooner it is diagnosed and properly treated, the better the prognosis. However, making a definitive diagnosis before the onset of substantial functional loss is difficult. By the time visual field deficits are detected, about 20% of the retinal ganglion cells (RGCs) are lost in the affected region. Spectral domain OCT is able to selectively analyze the innermost layers of the retina, including the RNFL, ganglion cell layer, and inner plexiform layer, which comprise the axons, bodies, and dendrites of RGCs, respectively. Static automated perimetry (SAP) is a subjective test, therefore poor patient compliance can greatly influence the reliability of its results. The multifocal VEP (MfVEP) uses a 60-sector checkerboard that subserves the central 22º and electrical responses to pattern stimuli are recorded. MfVEP is useful in optic neuropathies, such as glaucoma, and is shown to have defects that correlate with automated perimetry. It has been found to be an objective topographic assessment of the visual field in glaucomatous optic neuropathies and may be useful in patients with an unreliable subjective visual field. It may