The analysis of lacquer crack in the assessment of myopic choroidal neovascularization

The aim of this study was to clarify the characteristic findings in myopic choroidal neovascularization (CNV) and the relationship with lacquer crack (LC).

In all, 66 consecutive myopic CNV patients treated with photodynamic therapy and/or intravitreal anti-vascular endothelial growth factor injection in one eye were reviewed. Data from fluorescein angiography (FA) and indocyanine green angiography (ICGA), obtained simultaneously using the Heidelberg retina angiograph 2 (HRA2), were analyzed.

LCs were associated with a relatively large extent (≥3000 μm) of peripapillary choroidal atrophy and a dark rim, the proliferation of retinal pigment epithelial cells surrounding the neovascular membrane was accompanied by a small extent. Myopic CNV usually developed in the LC area surrounded by tiny crack fragments. In all, 35 patients with LCs received FA and ICGA at least twice during follow-up. LC progression was observed in nine (25.7%) treated eyes and six (23.1%) non-CNV fellow eyes. Crack fragments progressed in three distinct forms such as elongation, branching, or bridging pattern. Newly diagnosed myopic CNV was reported in 18 treated eyes and 3 fellow eyes. Progression of LCs and development of CNV occurred simultaneously in eight eyes. By multivariate Cox's regression, a statistically significant association was observed between recurrence of myopic CNV and the absence of a dark rim on ICGA.

The HRA2 instrument affords detailed high-resolution images of FA and ICGA. Notably, recurrence of myopic CNV developed in areas surrounded by new small crack fragments and LCs are considered to be important in the development of myopic CNV.