Prospective evaluation of changes in choroidal vascularity index after half-dose photodynamic therapy versus micropulse laser treatment in chronic central serous chorioretinopathy

Abstract

Purpose: To assess whether treatment of chronic central serous chorioretinopathy (cCSC) with photodynamic therapy (PDT) and high-density subthreshold micropulse laser (HSML) results in choroidal vascularity index (CVI) changes that may account for the treatment effect.

Methods: Patients with cCSC were prospectively included and analyzed. Patients received either half-dose PDT or HSML treatment. CVI of the affected and unaffected eye was obtained before treatment, 6 to 8 weeks after treatment, and 7 to 8 months after treatment.

Results: At baseline, 29 eyes (29 patients) were included both in the PDT and in the HSML group. The mean (± standard deviation) CVI change in the HSML group between before PDT and 6 to 8 weeks after PDT was - 0.009 ± 0.032 (p = 0.127), whereas this was 0.0025 ± 0.037 (p = 0.723) between the visit before PDT and final visit. The patients in the PDT group had a CVI change of - 0.0025 ± 0.037 (p = 0.723) between the visit before PDT and first visit after PDT, and a mean CVI change of - 0.013 ± 0.038 (p = 0.080) between the visit before PDT and final visit. There was no significant correlation between CVI and BCVA at the measured time points, in both the HSML group (p = 0.885), and in the PDT group (p = 0.904). Moreover, no significant changes in CVI occurred in the unaffected eye at any time point.

Conclusions: PDT and HSML do not significantly affect CVI, and therefore a CVI change may not be primarily responsible for the treatment effect. The positive treatment effect of both interventions may rely on other mechanisms, such as an effect on choriocapillaris and/or retinal pigment epithelium function.

Keywords: Central serous chorioretinopathy; Choroidal vascularity index; Micropulse laser; Photodynamic therapy.

Fig. 1

Optical coherence tomography imaging of the right eye (a–f) of a 41-year-old male patient affected with chronic central serous chorioretinopathy and treated with HSML. Baseline imaging (a–c) and final visit imaging obtained 7–8 months later (d–f), including the yellow segmentation lines (b, e) for the calculation of the CVI are depicted. The CVI is 0.6321 at baseline and changed to 0.5779 at final visit (change was not significant). CVI, choroidal vascularity index; HSML, high-density subthreshold micropulse laser

Fig. 2

Optical coherence tomography imaging of the right eye (a–f) of a 50-year-old male patient affected with chronic central serous chorioretinopathy and treated with PDT. Baseline imaging (a–c) and final visit imaging obtained 7–8 months later (d–f), including the yellow segmentation lines (b, e) for the calculation of the CVI are depicted. The CVI is 0.6677 at baseline and changed to 0.5910 at final visit. CVI, choroidal vascularity index; PDT, photodynamic therapy