Quantitative evaluation of photoreceptor density in chronic central serous chorioretinopathy using the Spectralis High Magnification Module

Purpose: To quantitatively evaluate the photoreceptor density in patients with chronic central serous chorioretinopathy (cCSC) using the Spectralis High Magnification Module (HMM). Methods: Twenty-four eyes of 24 patients with resolved cCSC, 24 fellow eyes from 24 other patients with unilateral cCSC, and 24 normal eyes of 24 healthy clients were enrolled in this observational case study. Photoreceptor densities of the retina in the nasal, temporal, superior, and inferior areas 500 mu m from the central fovea were counted manually through the High Magnification Module (HMM) images using ImageJ software, and the average values were taken for further analysis. Results: The mean photoreceptor density 500 mu m from the central fovea in the normal eyes (17,217 +/- 1144 cells/mm(2)) was significantly higher than that of both affected eyes (9721 +/- 1699 cells/mm(2)) and fellow eyes (15,667 +/- 1909 cells/mm(2)) (P < 0.001; P = 0.002, respectively). The mean photoreceptor density was significantly correlated with logMAR visual acuity (r = -0.432, P = 0.035), duration of symptoms (r = -0.537, P = 0.007), retinal sensitivity and fixation stability P2 in eyes with resolved cCSC (r = 0.430, P = 0.036; r = 0.420, P = 0.041, respectively). Conclusions: The HMM images revealed significant photoreceptor loss in patients with cCSC. The findings suggest that early intervention of the affected eyes, with short duration and good visual function, might be beneficial in preserving photoreceptor cells. As a novel imaging modality producing fast, high-resolution images, HMM shows great potential to detect microstructural impairments in retinal diseases.