2M.D. Associate Professor, Numune Training and Research Hospital, Eye Clinic, Ankara/TURKEY
3M.D. Asistant, Numune Training and Research Hospital, Eye Clinic, Ankara/TURKEY Purpose: We aimed to compare the pattern electroretinogram (PERG) amplitudes and retinal nerve fiber layer thicknesses (RNLF) determined by optical coherence tomography (OCT) in patients with ocular hypertension (OHT) and normal healthy subjects.
Material and Methods: Twenty-one normal subjects and 19 patients with OHT, totally 79 eyes of 40 patients were included in the study. Groups were classified as OHT (Group 1, n=37) and the control group (Group 2, n= 42). ERG was performed in all patients in different sessions (MetrovisionMonPack model visualelectrophysiology device brand) and Stratus OCT (Zeiss Stratus OCT Model 3000 instrument). P50 and N95 wave amplitudes; RNFL thickness parameters were recorded and the data were statistically compared. Student t test and Mann-Whitney U test was used forthe statistical analysis. Statistical significance at p<0.05 was accepted.
Results: Mean ages were comparable in both groups. Mean adjusted intraocular pressure (AIOP) was 23.4±2.2 mmHg in group 1 and 16.4±3.3 mmHg in group 2. The mean P50 values were 2.05±1.10 μv and 2.23±0.71 μv whereas N95 values were 4.07±1.56 μv and 4.45±1.41 μv for group 1 and group 2, respectively. Mean RNFL thickness values were 96.36± 9.06 μ and 93.94±9.31 μ respectively. There was no statistically significant difference between groups with respect to the PERG and RNFL analysis, (p>0.05).
Conclusion: In our study, there were no significant differences in both test methods between OHT group and normal population. However, it was thought that they might be of help in detecting early damage in OHT patients who were at high risk of conversion to glaucoma.
Keywords : Ocular hypertension, pattern electroretinogram, optical coherence tomography, retinal nerve fiber thickness