Decoding PERG: a Neuro-Ophthalmic Retinal Ganglion Cell Function Review

Purpose of ReviewCurrently, the clinical evaluation of neuro-ophthalmologic diseases is mainly focused on identifying stages where structural or functional damage occurs. Recognition of retinal ganglion cell (RGC) functional patterns as well as monitoring RGC dysfunction can be performed using steady-state pattern electroretinogram (PERG). The analysis of the amplitude and latency shift aids on providing information on early damage or monitoring of the RGC, allowing for prompt clinical intervention and management modification, potentially changing the natural history of the disease. The purpose of this article is to review the latest findings in PERG, in early manifest glaucoma, non-arteritic ischemic optic neuropathy, multiple sclerosis with unilateral recovered optic neuritis, and its fellow eyes.Recent FindingsThe steady-state PERG responses provide new and early specific information in neuro-ophthalmic diseases affecting the inner retina.SummarySteady-state PERG presents specific amplitude and latency outcomes based on the neuro-ophthalmic disease affecting the inner retina, allowing early recognition of changes at the level of RGC and the degree of RGC dysfunction. In addition, PERG alterations may be induced in healthy subjects as well as susceptible eyes using different stress tests such as head-down tilting or water-drinking tests.