Abstract
Purpose:
Central Serous Retinopathy (CSR) is a type of exudative retinal detachment that usually resolves spontaneously. This study examined CSR patients over time using multiple high-resolution imaging modalities to understand cone mosaic remodeling during and after subretinal fluid (SRF) resolution.
Methods:
6 active and 2 resolved CSR patients were imaged at baseline, and 3 active CSR patients were followed longitudinally at 6 weeks, 3 months and then every 3 months (ranging from 3-12 months) using adaptive optics scanning light ophthalmoscopy (AOSLO), spectral domain optical coherence tomography (OCT), and microperimetry (MP). At each visit, images were captured in areas overlying and adjacent to SRF. The cone mosaic was imaged using an AOSLO from Canon, Inc (Tokyo, Japan) and a custom AOSLO. Serial images were aligned using TrakEM2 (Institute of Neuroinformatics, University of Zurich) and Adobe Photoshop.
Results:
Areas where cones were separated from the retinal pigment epithelium (RPE) showed remodeling of the photoreceptor mosaic that continued months after SRF resolution. MP sensitivity was reduced 6-16dB (mean 10.2dB, SD 3.8dB) in areas of SRF but improved after SRF resolution and often was normal despite visible cone loss on AOSLO. The ellipsoid band (EB) on OCT was disrupted in areas overlying SRF and returned following SRF resolution. There was a trend toward improvement of visual acuity associated with SRF resolution and return of the EB on OCT. Hyperreflective clusters were visualized in the outer retina adjacent to SRF of two patients (mean diameter 19.1µm, SD 6.4µm). These varied in location over time and their disappearance was temporally associated with SRF resolution.
Conclusions:
Local disruption of the cone mosaic was observed following SRF resolution. The cone mosaic geometry varied over time in affected areas of diseased eyes, potentially showing remodeling of the cone mosaic as it reattaches to the RPE. The hyperreflective clusters may represent phagocytic cells engulfing cone outer segments while patients have SRF. The movement of clusters suggests motile cells and their size is similar to that of activated macrophages. The return of MP sensitivity to normal levels despite patchy areas of cone loss on AOSLO may be due to the relatively large stimulus area (~0.5 degrees). Future studies will continue to examine photoreceptor structure and function in retinal diseases with SRF.
Keywords: 550 imaging/image analysis: clinical •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
648 photoreceptors