Abstract
Purpose: :
To evaluate the correlation of retinal ganglion cell (RGC) activity with optic nerve head topography, retinal nevre fiber layer (RNFL) and macular thickness in eyes with primary open-angle glaucoma (POAG).
Methods: :
40 POAG patients and 23 age-matched controls in both eyes were enrolled in this study. Each study participant underwent detailed ophthalmologic examination, steady state pattern electroretinography (PERG), standard automated perimetry (SAP), Heidelberg Retinal Tomography (HRT-III) optic nerve head evaluation and optical chorence tomography (OCT) retinal nevre fiber layer and macular thickness analysis. PERG amplitudes were elicited by counterphased (16 reversals/second) high contrast (%99) checkboard patterns (1 degree). Included visual field indices were mean deviation (MD) and pattern standard deviation (PSD). RNFL thickness and macular thickness map were quantified by a standard protocol of Stratus OCT. Average, temporal, nasal, superior, inferior RNFL thicknesses and 9 segments in the macular thickness map were considered. Stereometric optic disc parameters were obtained by HRT. Pearson correlation coefficient was used for statistical analysis.
Results: :
Mean age of the patients with POAG and controls were 57,37 ± 8,6 years and 55,30 ± 8,09 years, respectively. PERG latency was not but PERG amplitude was significantly correlated with structural tests findings. OCT parameters; averaged RNFL thickness (r:0,755, p<0,001) and 6-mm-nasal area thickness of the macula (r:0,640, p<0,001) showed the most significant relationship with the RGC activity. Among SAP and HRT parameters; MD (r:0,507, p<0,001) and cup shape measure (r:0,480, p<0,001) revealed the best correlation coefficients.
Conclusions: :
Steady state PERG amplitude showed significant relationship with SAP, OCT, and HRT findings in POAG patients. RNFL and macular thickness analysis of the OCT showed the best correlation with PERG changes.
Keywords: electrophysiology: clinical • optic disc • ganglion cells