Quantitative evaluation of choriocapillaris using optical coherence tomography and optical coherence tomography angiography in patients with central serous chorioretinopathy after half-dose photodynamic therapy

Purpose To quantify the structural and perfusion changes in choriocapillaris in chronic central serous chorioretinopathy after half-dose photodynamic therapy by using spectral-domain optical coherence tomography and optical coherence tomography angiography. Methods This retrospective interventional case series examined the eyes of patients with central serous chorioretinopathy. Patients underwent full ophthalmic examinations, including spectral-domain optical coherence tomography and angiography, prior to and 1, 3, and 6 months after the treatment. Clinical and tomographic features of the choriocapillaris and choroidal thickness and vascular changes were evaluated by assessing flow signal voids. Results All 56 eyes of 56 patients showed complete resolution of subretinal fluid at 3 months after photodynamic therapy. The best-corrected visual acuity significantly improved at 6 months (p<0.001). The central subfield thickness, subfoveal choroidal thickness, subfoveal choroidal large vessel layer thickness, and mean total area of flow signal voids decreased significantly at 6 months (all p values < 0.001), but the subfoveal choriocapillaris layer thickness did not change significantly at 6 months (p >= 0.16). Multivariate analysis revealed positive linear correlations of the central subfield thickness and subfoveal choroidal large vessel layer thickness with the mean total area of flow signal voids at 6 months (p<0.001). There was a negative linear correlation between the subfoveal choriocapillaris layer and the mean total area of flow signal voids at 6 months (p = 0.013). Conclusion Half-dose photodynamic therapy improved the anatomic and functional outcomes of central serous chorioretinopathy, induced subfoveal choroidal thickness thinning, and increased choriocapillaris perfusion. In addition, the recovery of the subfoveal choriocapillaris layer thickness and improved choriocapillaris perfusion were closely associated.