Topographical relationship between the choroidal watershed zone and submacular idiopathic choroidal neovascularisation

AimsTo investigate the relationship between idiopathic choroidal neovascularisation (CNV) and choroidal watershed zones (CWZs) using indocyanine green angiography (ICGA).DesignMulticentre, retrospective, interventional case series.MethodsThe medical records and ICGA findings of 44 patients (44 eyes) diagnosed with idiopathic CNV were reviewed. CWZs, defined as hypofluorescence that disappeared during the early phase of ICGA, were classified, and the findings were compared with those of a control group of 30 eyes. The topographical relationship between CWZs and CNV was evaluated. Visual acuity and recurrence were analysed according to the CWZ classification.ResultsThe CNV lesion was subfoveal in 16 eyes, juxtafoveal in 12 eyes and extrafoveal in 16 eyes. The most common types of CWZs were stellate (23 eyes, 52.3%) and vertical (19 eyes, 43.2%). CWZs involving the fovea were seen in more patients with idiopathic CNV (37 eyes, 84.1%) than in the control group (11 eyes, 36.7%, p