Retinal ganglion cells function measured by the PERG test in patients with ocular hypertension

• Published in: Klinika oczna Vol. 113; no. 4-6; p. 122
• Main Authors: Wojciech, Lubiński, Wojciech, Gosławski, Krzysztof, Penkala, Zbigniew, Szych, Danuta, Karczewicz
• Format: Journal Article
• Language: English
• Published: Poland 2011
• Subjects: Adult; Electroretinography - methods; Female; Humans; Male; Middle Aged; Ocular Hypertension - diagnosis; Ocular Hypertension - pathology; Reference Values; Retinal Ganglion Cells - pathology; Retinal Ganglion Cells - physiology; Sensitivity and Specificity; Visual Acuity; Visual Field Tests; Visual Fields
• ISSN: 0023-2157

To assess the retinal ganglion cells function in patients with ocular hypertension (OHT). In one hundred eyes of 50 patients with ocular hypertension [mean age: 48 +/- 13 years, intraocular pressure mean: 26 +/- 3.0 mmHg; Humphrey Field Analyzer (HFA) 24-2 W-W mean deviation (MD) > -2 decibels (dB), normal optic nerve fiber layer results in scanning laser polarimetry (GDX)], PERG recordings were performed according to the modified methodology described by Parisi V et al. (Ophthalmology 2006; 113: 216-228). Main parameters measured in the PERG test were as follows: amplitude of the P50 and N95 waves, AN95/AP50 ratio as well as implicit time of P50 wave. Pattern Electroretinogram P50 implicit times were considered delayed when exceeding the limit of mean values plus 2 standard deviations (SDs) from controls. PERG amplitudes of P50, N95 waves and AN95/AP50 ratio were considered reduced when they were below the mean values minus 2 SDs from controls. Control group consisted of age, sex, and refractive error matched one hundred eyes of 50 healthy subjects with intraocular pressure mean equal to 16 +/- 4.0 mmHg. In the OHT eyes, significant reductions of AN95-wave (p < 0.0002) and AN95/AP50 ratio (p < 0.002) were obtained in comparison to controls. The PERG test revealed the abnormalities mostly in AN95/AP50 ratio (32/100 of OHT eyes--32%). Other less frequent abnormalities were observed in amplitude of N95-wave (10/100 of OHT eyes--10%) and in amplitude of P50-wave (6/100 of OHT eyes--6%). The implicit times of P50 and N95-waves were within normal limits. In the eyes of the OHT patients, retinal ganglion cells dysfunction is present and can be detected by the PERG test. Longer follow-up is necessary to show predictable value of the PERG examination in separation of the OHT patients with a high risk of glaucoma development.