Efficacy of half-fluence photodynamic therapy depending on the degree of choroidal hyperpermeability in chronic central serous chorioretinopathy

Purpose

The purpose of this study is to determine the efficacy of half-fluence photodynamic therapy (PDT) depending on the degree of hyperfluorescence based on indocyanine green angiography (ICGA) for treatment of chronic central serous chorioretinopathy (CSC).

Methods

We conducted a prospective study of 30 eyes of 30 patients with chronic CSC. Half-fluence PDT (25 J/cm² for 83 s) with ICGA guidance was applied to the area of choroidal hyperpermeability. The baseline middle-phase ICGA findings were classified as intense or weak hyperfluorescence depending on the degree of hyperpermeability from choriocapillaris. Changes in mean best-corrected visual acuity, resolution of subretinal fluid, recurrence rate, and complications were compared between the two groups.

Results

The baseline ICGA findings showed intense hyperfluorescence in 16 eyes (53.3%) and weak hyperfluorescence in 14 eyes (46.7%). Subretinal fluid showed complete resolution in both the groups 1 month after a single application of half-fluence PDT. Recurrence of subretinal fluid was observed in one of 14 eyes (7.1%) with weak hyperfluorescence and in no eyes (0%) with intense hyperfluorescence. No statistically significant difference in the rate of recurrence was observed between the two groups.

Conclusion

Half-fluence PDT appears to be an effective and safe treatment option for patients with chronic CSC regardless of the degree of hyperfluorescence based on ICGA. According to these findings, choroidal hyperpermeability, rather than dysfunction of retinal pigment epithelium, might be more important as primary pathogenesis of chronic CSC.