Ultrahigh Resolution Spectral Domain Optical Coherence Tomography for the Assessment of Micro-Structural Changes in Central Serous Chorioretinopathy: A Pilot Study.

Abstract

Purpose : In central serous chorioretinopathy (CSCR), choroidal hyperpermeability associated with retinal pigment epithelium (RPE) impairment causes a leakage of fluid from the choroid into the subretinal space, with potential damage to the photoreceptors. We hypothesize that ultrahigh-resolution spectral domain optical coherence tomography (UHR SD-OCT) will enable more detailed assessment of structural changes in this condition.

Methods : Patients in all stages of CSCR (acute, chronic and post-resolution) were imaged using an UHR SD-OCT prototype, with an 850 nm center wavelength and an axial resolution of ~2.7 µm in tissue at a 128kHz A-scan rate. Volumetric cube scans and high-density (HD) scans were acquired covering 6×6 mm² and 9×6 mm² fields of view, respectively. Comparative images were also obtained using a commercial SD-OCT device, with an axial resolution of 5 µm in tissue at a 68 kHz A-scan rate. For post-resolution CSCR cases, a qualitative assessment of the integrity of the outer retina bands (interdigitation zones, inner segment (IS), outer segment (OS) and IS/OS junction / ellipsoid zone) and BM-RPE complex was performed. For acute and chronic cases, the integrity of RPE-BM complex at the leakage site was assessed qualitatively.

Results : To date, 7 eyes of 7 patients were imaged. Results show that UHR SD-OCT images allowed superior visualization and resolution of outer retina bands and its defects compared to the commercial SD-OCT (Figure 1). Further data collection and analysis of the RPE-BM complex in relation to the leakage site are ongoing.

Conclusions : UHR SD-OCT allows a more detailed assessment of structural changes in CSCR, in its acute, chronic and post-resolution phases. The ability to detect subtle structural changes in the BM-RPE complex of patients with acute CSCR may improve the understanding of disease pathophysiology.

This is a 2020 Imaging in the Eye Conference abstract.

 

Examples of three CSCR cases imaged concurrently on the UHR SD-OCT system (A, C & E) and a commercial SD-OCT system (B, D & F). All images are of unaveraged B-scans, acquired on a volumetric scan protocol. A & B: B-scans of an acute CSCR case. C & D: B-scans of a post-resolution case. E & F: B-scans of a chronic CSCR case.