Abstract
Purpose :
A recent study 1 has shown that adaptive changes in the pattern electroretinogram (PERG adaptation) are altered in eyes with early manifest glaucoma, indicating reduced autoregulation and energy budget mechanism in affected eyes. The aim of this study was to evaluate PERG adaptation in glaucoma suspect (GS) eyes and to correlate the results with early anatomical changes in retinal ganglion cells (RGCs) and optic nerve fibers (ONF)
Methods :
Twenty-one GS patients and 20 age-matched controls were included in the study. PERGs were recorded in response to 7.5 Hz counterphased horizontal bars (field size 50 x 60 °, 90% contrast) presented in 9 packets of 60 events each and alternated with an unmodulated uniform field. Trends of PERG amplitude and phase changes as a function of stimulus packets were measured with vector response analysis and linear regression statistics for amplitude values1. Regression coefficients and phase coherence were determined for each measure
Results :
PERG adaptation was detected and significant (p < 0.05/p < 0.01) in all control subjects, with a mean decline as a function of packets of -3 microV/packet. PERG adaptation had a shallower negative slope in glaucoma suspects, compared to controls, with a mean decline of -0.46 microV/packet (p < 0.01). Regression coefficients and phase coherence were also reduced in GS patients compared with controls. No significant correlations were found between PERG adaptation parameters and RCG and ONF thickness of patients
Conclusions :
In GS patients, the PERG adaptation is abnormal and not correlated with anatomical changes, suggesting that inner retina autoregulation and energy budget mechanisms are altered early,and independently of anatomical damage, in the disease process
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.