title: Comparison of efficacy and safety between half-fluence and full-fluence photodynamic therapy for chronic central serous chorioretinopathy.
abstract: OBJECTIVE
  To compare the efficacy and safety of half-fluence photodynamic therapy (PDT) and conventional PDT in chronic central serous chorioretinopathy.
  
  
  METHODS
  A multicenter retrospective comparison study. Retrospective review of 60 patients including 29 patients (34 eyes) who received half-fluence PDT and 31 patients (33 eyes) who received conventional PDT for the treatment of chronic central serous chorioretinopathy. Best-corrected visual acuity, central fovea retinal thickness and resolution of subretinal fluid on optical coherence tomography, and choroidal perfusion decrease on indocyanine green angiography were assessed. Choriocapillaris perfusion decrease was quantified as mean gray value ratio of treated and nontreated areas using commercial imaging software.
  
  
  RESULTS
  Treatment success without recurrence was achieved in 32 of 34 eyes (94.1%) treated with half-fluence PDT and 33 of 33 eyes (100%) treated with conventional PDT (P = 0.493). There was no difference in final best-corrected visual acuity (logarithm of the minimal angle of resolution) between the 2 groups (0.17 ± 0.32 vs. 0.21 ± 0.39; P = 0.603). Choriocapillaris perfusion decrease quantified from post-PDT indocyanine green angiography was significantly more severe in the conventional PDT group (P = 0.006), and it showed a positive correlation with retinal thinning after PDT (R = 0.380; P < 0.001).
  
  
  CONCLUSIONS
  Half-fluence PDT is as effective as conventional PDT, while minimizing the deleterious effect on choriocapillaris perfusion and retinal thickness.
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Joo Young
authors.initials: JY
authors.lastname: Shin
authors.forename: Se Joon
authors.initials: SJ
authors.lastname: Woo
authors.forename: Hyeong Gon
authors.initials: HG
authors.lastname: Yu
authors.forename: Kyu Hyung
authors.initials: KH
authors.lastname: Park
mesh_terms: D000328:Adult; D056833:Central Serous Chorioretinopathy / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D002829:Choroid / Q000098:blood supply; D002908:Chronic Disease; D004396:Coloring Agents; D005139:Eyeglasses; D005260:Female; D005584:Fovea Centralis / Q000187:drug effects / Q000473:pathology; D006801:Humans; D007208:Indocyanine Green; D008297:Male; D008875:Middle Aged; D010778:Photochemotherapy / Q000009:adverse effects* / Q000379:methods*; D012008:Recurrence; D012039:Regional Blood Flow / Q000187:drug effects; D012160:Retina / Q000473:pathology; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D014792:Visual Acuity / Q000187:drug effects
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green