Abstract
Purpose :
We have previously identified an inverse relationship between high contrast (Hc) and low contrast (Lc) visual evoked potential (VEP) latency in fellow eyes of certain glaucoma patients. The current study was undertaken to characterize electroretinogram (ERG) parameters in glaucoma patients displaying an inverse VEP latency relationship.
Methods :
Clinical records of 440 adult glaucoma patients and suspects who underwent Diopsys® NOVA-LX to measure VEP Hc & Lc latency were reviewed to identify individuals with one significant Hc or Lc latency defect in each eye as determined by the device's intrinsic software. Exclusion criteria included eyes with any other ocular disease, TBI, unexplained visual loss, demyelinating conditions and neuropathies. The records of 32 patients that met the inclusion criteria were reviewed to identify those patients with Diopsys NOVA contrast sensitivity ERG results available for analysis.
Results :
14 (10F, 4M) of 32 patients (44%) had ERG data available for analysis. Their mean age (54.6y) did not differ significantly from the 18 patients without ERG data (p=0.88). There was no statistically significant difference between Magnitude (Mag) or Magnitude-D (MagD) between right and left eyes under Hc or Lc stimulus conditions. Linear regression analysis revealed significant positive correlation between Hc and Lc Mag (P = 0.01, r2 = 0.22) and between Hc and Lc Mag-D (P = 0.0002, r2 = 0.41) (FIGURE, panels A and C). In addition, there was significant positive correlation between right and left eyes for Mag (P < 0.0001, r2 = 0.63) and MagD (P = 0.0001, r2 = 0.44) (FIGURE, panels B and D).
Conclusions :
Patients demonstrating significant negative correlation between Hc and Lc VEP latency demonstrate significant positive correlation in Hc and Lc ERG Mag and MagD. These findings suggest that the observed inverse VEP correlations may originate at centers above the level of the retina.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.