Design and Baseline Characteristics of the HELP Study: An Extended and Long-Term Observation of Pathological Myopia in Caucasians.

<b><i>Purpose:</i></b> To assess the natural disease progression of high myopia in Caucasians considered at risk for the development of myopic choroidal neovascularization (mCNV). <b><i>Methods:</i></b> Subjects were recruited in 25 clinical sites between June 2014 and June 2016. Main inclusion criteria included axial length of ≥26 mm, best-corrected visual acuity ≥0.05 decimal equivalent and presence of at least one out of five predefined morphological disease risk criteria. These were (1) subfoveal choroidal thinning < 50 µm, (2) enhanced choroidal curvature length > 6,300 µm, (3) lacquer cracks, (4) patchy atrophy &#x3…