Epidemiology and Diagnosis of Myopic Choroidal Neovascularization in Asia.

BACKGROUND: This article aims to review recent advances in the understanding of epidemiology and risk factors for the development of myopic choroidal neovascularization (CNV) and highlight the diagnostic features of myopic CNV and signs seen on the noninvasive optical coherence tomography technology, which may be particularly useful for the purpose of screening. Choroidal neovascularization is a sight-threatening complication of pathologic myopia. Because myopic CNV frequently affects individuals during their working life, its socioeconomic impact is significant, especially in Asian countries where the prevalence of pathologic myopia is high. EPIDEMIOLOGY: Pathological myopia is the most common cause of CNV in patients less than 50 years old, and it is estimated that 5.2% to 11.3% of individuals with pathologic myopia develop myopic CNV. RISK FACTORS: The risk of developing myopic CNV increases with the severity of myopia and macular changes, such as diffuse atrophy, lacquer cracks, and patchy atrophy, which progress to myopic CNV in a significant proportion. Vascular endothelial growth factor (VEGF) may contribute to the development of myopic CNV. NATURAL COURSE AND PROGNOSIS: Untreated myopic CNV carries a poor visual prognosis, with an estimated 89% of the patients having marked visual impairment within 5 years of onset. TREATMENT: Anti-VEGF therapy is efficacious in treating myopic CNV. Although this significantly improves the short-term prognosis of myopic CNV, the long-term visual loss due to the sequela of myopic CNV including macular atrophy and scarring remains.