Central serous chorioretinopathy (CSC) is one of the representative pachychoroid spectrum disease. Although fundus fluorescein angiography and indocyanine green angiography can be used as the gold standard for the diagnosis of CSC, they are invasive examinations, which may bring certain risks in clinical application and cannot help us obtain quantitative parameters. Optical coherence tomography angiography (OCTA), as a non-invasive and quantitative examination, is an important imaging tool for understanding the pathogenesis, diagnosis and treatment of CSC. With the advancement of OCTA, the swept-source OCTA has a satisfying scanning depth, a wider scanning range and a higher resolution. The development of OCTA broadens the horizons of the pathogenesis of CSC, promotes the understanding of the pathophysiology of CSC, and sheds new light for its clinical diagnosis and treatment. Based on OCTA, the choroid and retina in eyes with CSC are presented with qualitative and quantitative changes in vascular system. OCTA-guided CSC treatment and the discovery of prognostic markers based on OCTA challenge the application of traditional imaging techniques in CSC. With the continuous improvement and progress of OCTA technology, traditional angiography combined with OCTA will bring great benefits to the diagnosis and treatment of CSC. This review summarizes the quantitative application of OCTA in the pathogenesis, diagnosis and treatment of CSC.
ObjectiveTo analyze the associations between the choroidal vasculature and submacular fluid (SMF) in central serous chorioretinopathy (CSC). MethodsA retrospective study. A total of 29 CSC patients (31 eyes) with complete records who visited the Department of Ophthalmology in Peking University People's Hospital from August 1, 2021 to March 1, 2023 were included in this study. The patients were divided into complete absorption and incomplete absorption groups according to the status of SMF in the last visit. All the patients underwent ultra-widefield swept-source optical coherence tomography angiography (UWF SS-OCTA) with a scanning range of 24 mm × 20 mm. The UWF SS-OCTA images were automatically analyzed in 9 regions (superotemporal, superior, superonasal, temporal, central, nasal, inferotemporal, inferior, and inferonasal). Alterations of choroidal vasculature in the nine subfields after SMF absorption were described, including choroidal thickness (CT), flow density of choriocapillaris layer, vessel density of large choroidal vessel layer, three-dimensional choroidal vascularity index (CVI), the mean choroidal vessel volume (mCVV), and the mean choroidal stroma volume (mCSV). The relevant factors affecting the complete absorption of SMF were additionally evaluated. ResultsAt baseline, CT (Z=2.859, P=0.004), mCVV (t=2.514, P=0.018), and mCSV (Z=2.958, P=0.003) in the superotemporal region of the affected eyes in the incomplete absorption group were significantly higher than those in the complete absorption group. Compared with baseline, at the last visit, the proportion of asymmetric vortex veins in the complete absorption group was significantly decreased (χ2=6.000, P=0.014), CVI in the superotemporal, superonasal, temporal, central, nasal, inferotemporal, and inferonasal regions (t=－4.125, t=－3.247, Z=－3.213, t=－2.994, t=－3.417, t=－3.733, t=－3.795; P=0.001, 0.006, 0.001, 0.010, 0.005, 0.003, 0.002), the mCVV of 9 regions (t=－2.959, t=－2.537, t=－2.235, t=－3.260, t=－3.022, t=－2.796, t=－2.747, Z=－2.107, t=－2.935; P=0.011, 0.025, 0.044, 0.006, 0.010, 0.015, 0.017, 0.035, 0.012) were significantly decreased. Compared to the complete absorption group, the choroidal blood flow changes in the non-complete absorption group were more limited, and CT in the upper region increased significantly at the last follow-up (t=2.272, P=0.037). Multivariate logistic regression analysis revealed that baseline CT in the superotemporal region may be an independent risk factor affecting the complete absorption of SMF (odds ratio=0.981, 95% confidential interval 0.965-0.997, P=0.021). ConclusionsIn the process of SMF absorption in CSC, significant reductions of choroidal blood flow were found in the large choroidal vessel layer, and there may be a locally compensatory increase in CT. In addition, baseline CT in superotemporal region is an independent risk factor affecting SMF absorption.