Delay of Pattern Electroretinogram Peaks and Its Correlation to Contrast Threshold for Motion Perception in Glaucoma

Abstract

Peak latencies of pattern electroretinogram (PERG) were compared between glaucomatous eyes and non-glaucomatous eyes. Contrast threshold for motion pecpetion (CTMP) was also measured with a new device in addition to routine static contrast sensitivity, static visual field and visual acuity. In the present recording, configurations for PERG, i.e. low reversal rate, low mean luminance and presence of background illumination, the PERG peak and trough (P₁ and N₂, respectively) hatencies, were significantly prolonged in the glaucomatous eyes. Although both of the two PERG latencies were strongly correlated with the CTMP, only the P₁ peak latency was strongly correlated with the perimetric indices. These results suggest that the P₁ and N₂ latencies reflect different aspects of signal processing in the retina, especially for moving targets.

Impaired visual function in glaucoma

“…The retinal function has been assessed by PERG recordings and, in agreement with previous electrophysiological studies (Bobak et al, 1983;Wanger and Persson, 1983;Marx et al, 1986a;Porciatti et al, 1987;Watanabe et al, 1990;O'Donaghue et al, 1992;Bray et al, 1992;Pfeiffer et al, 1993;Arai et al, 1993;Graham et al, 1994Graham et al, , 1996Komata et al, 1995;Parisi, 1997), our POAG patients presented impaired PERG responses (delayed latencies and reduced amplitudes). Since it is known that the integrity of the innermost retinal layers is essential for the generation of a normal PERG response (Parisi et al, 1999c) and in glaucoma a loss of ganglion cells and their ®bers has been documented by histological studies (Quigley et al, 1982(Quigley et al, , 1987(Quigley et al, , 1988(Quigley et al, , 1995 and by morphological evaluation in vivo of the retinal ®bers (Orzalesi et al, 1998;Shuman et al, 1995;Yucel et al, 1998), the impaired PERG responses observed in our glaucomatous patients could be ascribed to a dysfunction of ganglion cells and their ®bers.…”

Correlation between morphological and functional retinal impairment in patients affected by ocular hypertension, glaucoma, demyelinating optic neuritis and Alzheimer’s disease

“…According to several studies revealing a retinal dysfunction in patients affected by ocular hypertension, 29,52-58 glaucoma, 29,30,33,[59][60][61][62][63][64] demyelinating optic neuritis, [65][66][67][68][69][70][71] and Alzheimer's Disease, 37,72,73 we observed, in the same categories of patients, abnormal PERG responses with delayed implicit times and reduced amplitudes. In our patients the impairment in PERG parameters was significantly correlated to the reduction in NFL thickness.…”

The role of pattern-reversal electroretinography in the diagnosis of glaucoma

“…Ringens and Parisi observed a delay in the PERG response in glaucoma patients (50,82) and Komata found a prolonged P50 peak time (83) . With regard to OHT, Arai et al reported an elongated latency of P50 (62) and Marx et al reported a delay in mean PERG latency (84) .…”