Abstract
Purpose :
The pattern electroretinogram (PERG) is the electroretinal response to contrast reversal of pattern stimuli which reflects functional integrity of retinal ganglion cells and their axons. The uniform field electroretinogram (UF-ERG) to stepwise luminance modulation of low temporal frequency allows the separation of responses to light increments and decrements (Viswanathan et al. 2000) and has been described in non-human primates with experimental glaucoma. The UF-ERG has not been previously described in human subjects.
Methods :
UF-ERG and PERG were recorded in 18 subjects (36 eyes) aged 20-75 years. For UF-ERG luminance modulation was provided by an 800x600 pixel OLED stimulator (Diagnosys LLC) subtending a 24x32 degree viewing angle producing a luminance of 300 cd/m2 for a 200 msec duration. 220 replications of 230 msec sweep duration were obtained at both stimulus onset and stimulus offset and averaged. The PERG was recorded to .8 degree checksize at 2 reversals/second and 150 sweeps were signal averaged.
Results :
There was a significant difference in peak latency of the P50 component of the UF-ERG and PERG (p<.0001). No significant difference was found in the N95 component peak latency. In addition, there were no significant differences in P50 or N95 amplitude measures.
Conclusions :
The UF-ERG can be reliably recorded in human subjects. The response is similar in amplitude to the PERG P50 and N95 components. The obvious advantages of using a non-patterned stimulus which does not require steady fixation and refractive correction make the UF-ERG an ideal stimulus for clinical investigation of optic neuropathy.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.