Long-term outcome of macular neovascularization secondary to choroidal osteoma with and without intravitreal anti-VEGF(vascular endothelial growth factor)- treatment

Background: Choroidal osteoma (CO) is a benign ossifying ocular tumor, which is unilateral in most cases. The CO may cause severe visual impairment, especially in the case of a secondary macular neovascularization (MNV). Objective: Based on a case series of patients with MNV secondary to CO, the variability of the clinical course with and without intravitreal anti-vascular endothelial growth factor (VEGF) treatment is presented. Methods: All patients diagnosed with secondary MNV due to CO between 2007 and 2023 were retrospectively assessed with respect to the clinical course. Results: In this study 7 eyes of 5 patients (4 women, 1 man) were diagnosed with secondary MNV due to CO. Intravitreal anti-VEGF treatment was carried out in 2 patients with unilateral MNV and 1 patient was treated in both eyes for bilateral MNV. In another case with bilateral MNV, only 1 eye was treated because of fibrosis in the other eye. A further case with unilateral CO and MNV scars at the initial diagnosis was left untreated. Overall, in 3 out of 5 eyes treated with intravitreal VEGF inhibition stabilization or improvement of visual acuity could be achieved. Conclusion: In our case series intravitreal anti-VEGF treatment attained a functional stabilization or improvement in 3 out of 5 treated eyes. In one case of CO-associated MNV fibrosis rapidly developed without treatment. Therefore, the clarification for patients with CO about the lifelong risk for development of a secondary MNV is essential in individual cases for early treatment. As no standardized treatment scheme for intravitreal VEGF antibodies for CO-related MNV exists, the treatment is planned on an individual basis.