Focal and Diffuse Chronic Central Serous Chorioretinopathy Treated With Half-Dose Photodynamic Therapy or Subthreshold Micropulse Laser: PLACE Trial Report No. 3

To compare the outcome between high-density subthreshold micropulse laser (HSML) treatment and half-dose photodynamic therapy (PDT) in chronic central serous chorioretinopathy (cCSC) patients, subdivided based on either focal or diffuse leakage on fluorescein angiography (FA). Retrospective analysis of multicenter randomized controlled trial data. Patients were treated with either half-dose PDT or HSML (both indocyanine green angiography–guided) and categorized in 2 groups, based on focal or diffuse leakage on FA. Clinical outcomes were evaluated at baseline and during follow-up. In the focal leakage group (63 patients), both at first evaluation and at final visit, more PDT-treated than HSML-treated patients demonstrated a resolution of subretinal fluid (evaluation visit 1: 57% in the PDT group and 17% in the HSML group, P = .007; final visit: 75% and 38%, P = .012). In the diffuse leakage group (93 patients), both at first evaluation and at final visit, more PDT-treated than HSML-treated patients showed a resolution of subretinal fluid (evaluation visit: 1:48% in the PDT group and 16% in the HSML group, P = .002; final visit: 67% and 21%, P = .002). PDT-treated patients in the focal and diffuse leakage group had a higher retinal sensitivity increase, comparing baseline and final visit (+3.1 ± 3.1 dB vs +1.2 ± 4.0 dB, P = .048, and +2.7 ± 3.3 dB vs +1.0 ± 3.8 dB, P = .036, respectively). Only in the diffuse leakage group, the increase in ETDRS letters was higher in the PDT-treated group when comparing baseline and first evaluation visit (+4.4 ± 6.1 vs +0.9 ± 10.0, P = .049). Half-dose PDT is superior to HSML treatment in cCSC patients, regardless of the presence of focal or diffuse leakage on FA.