Subthreshold Laser as Alternative Treatment for Chronic Central Serous Chorioretinopathy - A Case Series

Abstract

Purpose: Subthreshold laser is a relatively new and promising therapy for chronic central serous chorioretinopathy (CSCR), particularly in regions where current mainstay therapy in the form of Indocyanine green (ICG)-based photodynamic therapy (PDT) is either too expensive or unavailable. We reported the clinical efficacy of the nondamaging subthreshold laser therapy for chronic CSCR using Endpoint Managementâ„¢ system.

Patients and methods: Eyes with unresolved, chronic CSCR of more than 3 months of duration were treated using PASCAL® (Topcon Medical Laser System) Streamline at 577-nm wavelength, using 200 μm retinal spot sizes. Using Endpoint Management™ Software, the laser power was first titrated with 15-ms pulses and applied over the area of serous retinal detachment and adjacent non-thickened retina using 30% pulse energy with 0.25 spot spacing. Serous retinal detachment was measured between the outer surface of the neurosensory retina and the retinal pigment epithelium (CIRRUS™ HD-OCT, Carl Zeiss Meditec, Inc). Changes in subretinal fluid (SRF) and best corrected visual acuity (BCVA) were measured over 3 months of follow-up as primary outcomes.

Results: Thirteen eyes of thirteen patients (twelve male, one female) age 43 (26-63) years were included in this study. The median duration of symptoms was 12 (4-24) months. All subjects complained of metamorphopsia at first visit. Overall, the laser parameters used were 288 ± 95.36 shots and 122.50 ± 11.65mW (power). Twelve eyes (92.31%) showed a decrease of subretinal fluid, with baseline SRF value of 224 (61-375) μm and final SRF of 16 (0-154) μm. Twelve from thirteen eyes (92.31%) also recorded improved or stable BCVA [0.8 (0.5-1.0) at baseline vs. 1.0 (0.2-1.0) at the final visit] with 10 eyes (76.92%) recorded final BCVA of 1.0. Complete resolutions of SRF were found in six (46.13%) eyes. It took 12.5 (7-14) weeks to achieve complete SRF resolutions.

Conclusion: Subthreshold laser therapy can improve visual acuity and enable the resolution of SRF in chronic CSCR. It may offer as an alternative to photodynamic therapy, anti-vascular endothelial growth factor, or conventional laser therapy. All of which are previously used for the treatment of chronic CSCR.