Choroidal neovascularization in angioid streaks following microincision vitrectomy surgery: a case report

Background: Patients with angioid streaks are prone to developing subretinal hemorrhage after ocular or head injury due to the brittleness of Bruch's membrane. However, there have been no reports of any angioid streak patients in whom choroidal neovascularization occurred after vitrectomy surgery. We report herein a patient with angioid streaks who developed choroidal neovascularization after vitrectomy surgery for epiretinal membrane. Case presentation: A 76-year-old man presented with distorted vision in his left eye, with a best corrected visual acuity of 1.2 and 0.6 in his right and left eyes, respectively. Fundus examination showed angioid streaks in both eyes and epiretinal membrane only in the left eye. The patient underwent 23-gauge three-port pars plana vitrectomy with removal of the epiretinal membrane combined with cataract surgery. Internal limiting membrane in addition to the epiretinal membrane were successfully peeled and removed, with indocyanine green dye used to visualize the internal limiting membrane. His left best corrected visual acuity improved to 0.8. An elevated lesion with retinal hemorrhage due to probable choroidal neovascularization was found between the fovea and the optic disc in the left eye at 7 weeks after surgery. Since best corrected visual acuity decreased to 0.15 and the hemorrhage expanded, posterior sub-Tenon injection of triamcinolone acetonide was performed. However, no improvement was observed. Even though intravitreal bevacizumab injection was performed a total of five times, his best corrected visual acuity remained at 0.1. Subsequently, we performed a combination treatment of a standard-fluence photodynamic therapy and intravitreal ranibizumab injection, with additional intravitreal ranibizumab injections performed 3 times after this combination treatment. Best corrected visual acuity improved to 0.5 and the size of the choroidal neovascularization markedly regressed at 4 months after the combined treatment. Conclusion: Development of choroidal neovascularization could possibly occur in elderly patients with angioid streaks after vitrectomy surgery. In such cases, a combination of photodynamic therapy and intravitreal ranibizumab injection may be considered for initial treatment of the choroidal neovascularization.