Changes in the Foveal Outer Nuclear Layer of Central Serous Chorioretinopathy Patients Over the Disease Course and Their Response to Photodynamic Therapy

Abstract

Objective:To investigate the association between foveal outer nuclear layer (ONL) thickness and the natural course of central serous chorioretinopathy (CSC), as well as the thickness change after photodynamic therapy (PDT), exploring the PDT timing for CSC.Methods:This retrospective consecutive case series included 358 CSC patients between January 2014 and December 2019. All patients were divided into four groups depending on disease duration: Group A: ≤1 month; Group B: >1 and ≤3 months; Group C: >3 and≤6 months and Group D: >6 months. Foveal ONL thickness of the CSC eye and the clinically healthy fellow eye were measured and compared in all patients. Fifty-six patients were successfully treated with half-dose of PDT, showing complete subretinal fluid absorption, were followed up for more than 6 months and further investigated. The recovery of foveal ONL thickness was analyzed in the affected eyes of patients with different disease duration.Results:No significant reduction was found in CSC foveal ONL thickness (μm) compared to the fellow eye in patients with disease duration less than 1 week (112.3 ± 12.2 vs. 116.7 ± 15.3, P = 0.268). Patients with longer disease duration had varying degrees of ONL thinning compared to the contralateral eye (all P < 0.05) and this difference was more pronounced in patients with disease duration greater than 6 months (75.8 ± 12.9 vs. 113.0 ± 11.5, P < 0.001). At 6-month follow-up after PDT, foveal ONL thickness of patients with <1 month disease duration recovered significantly from onset (97.3 ± 18.2 to 113.6 ± 8.7, P < 0.001) and became similar to that of the healthy fellow eye. Foveal ONL thickness of patients with duration>1 and≤3 months recovered significantly (88.5 ± 11.5 to 95.8 ± 11.3, P = 0.012) but remained thinner than that of the healthy fellow eye. Foveal ONL thickness did not improve significantly in cases with disease duration longer than 3 months (P > 0.05).Conclusion:Foveal ONL thinning was positively associated with disease duration prior to treatment suggesting that longer disease duration limits scope for foveal ONL recovery. CSC patients should be treated with PDT as soon as possible to prevent disease development and reduced visual function.

Chronic Central Serous Chorioretinopathy in Elderly Subjects: Structure and Blood Flow Characteristics of Retina and Choroid

“…The thinner the ONL and the lower the BCVA, the higher the incidence of EZ- [ 26 ]. Mingwei Zhao et al [ 27 ] believed that the thinning of foveal ONL was positively correlated with the course of CSC, and the longer duration of disease limited the recovery of foveal ONL. ONL is composed of pyramidal cell bodies, so the decrease of ONL thickness indicates that the number of pyramidal cells decreases.…”

Importance of OCT-derived Biomarkers for the Recurrence of Central Serous Chorioretinopathy using Statistics and Predictive Modelling

“…In particular, changes in central macular thickness and subfoveal choroidal thickness were associated to the resolution of CSCR, while the amount of SRF to the visual acuity outcomes. Moreover, the morphology of the retinal layers, such as ONL thinning, PR layer elongation, ELM and ellipsoid zone disruption was previously associated with longer duration of SRF and worse visual acuity [17,28,29].…”

Baseline Spectral Domain Optical Coherence Tomographic Retinal Layer Features Identified by Artificial Intelligence Predict the Course of Central Serous Chorioretinopathy

“…[21][22][23] In a retrospective study on 358 patients with CSC, ONL thinning was found to be proportional to disease duration, with more pronounced differences detected after a disease duration of 6 months. 24 Piccolino et al categorized the eyes of CSC patients with PR layer elongation, which is a stretch of PR length, including the external limiting membrane, the ellipsoid zone, and the interdigitation zone because of SRF in two subgroups: the first group with a preserved anatomy of the outer retinal layers, associated with a better long-term visual prognosis, and a second group, characterized by atrophic changes in the PR layer and poorer visual outcomes. 25 In a recent study, a thinning of the PR layer above the point of focal leakage on fluorescein angiography was found in patients with aCSC as a sign of mild outer retina atrophy.…”