ETIOLOGY OF CHOROIDAL NEOVASCULARIZATION IN YOUNG-PATIENTS

Background: Choroidal neovascularization (CNV) is a common cause of le gal blindness in developed countries. In patients younger than 50 year s of age, CNV can be due to various causes, but to the authors' knowle dge there has been no large epidemiologic study to compare the relativ e incidence of the various causes of CNV in this younger-aged group. M ethods: A retrospective study was performed of patients seen over a 30 -month period to precisely define the relative incidence of the variou s etiologies of CNV in patients younger than 50 years of age who had b een referred to a tertiary care ophthalmology department in western Eu rope. Results: Clinical charts and angiograms of 363 patients were rev iewed. The etiology of CNV was high myopia in 225 (62%) patients, pseu do-presumed ocular histoplasmosis syndrome in 42 (12%), angioid streak s in 17 (5%), and miscellaneous hereditary, or traumatic or inflammato ry disorders in 16 (4%). Choroidal neovascularization could not be rel ated to any etiology in 63 (17%) patients, and was considered to be id iopathic lesions. Choroidal neovascularization was subfoveal in 62% of the patients due to myopia versus 30% to 36% in patients due to other etiologies. Laser photocoagulation was applied in the majority of pat ients due to all etiologies except myopia. Conclusion: These data prov ide the relative incidence of the various etiologies of CNV in young p atients and emphasize the importance of myopia as an etiology of CNV i n such patients. In addition, an apparent preferential localization of CNV to the subfoveal region in myopic eyes precludes its treatment wi th photocoagulation.