Dexamethasone Implant Migration through an Iris Coloboma

Abstract

Ozurdex® 0.7 mg (dexamethasone 0.7 mg implant, Allergan, Dublin, Ireland), an intravitreal biodegradable implant, is indicated for cystoid macular edema due to various causes. One of its known and uncommon complications is implant migration to the anterior chamber, causing corneal edema that, in some cases, is irreversible. Reported risk factors for device migration are open or defective lens capsule and prior history of vitrectomy. We present a case of dexamethasone implant migration through a congenital iris coloboma in a pseudophakic patient with an intact lens capsule. The patient is a 56-year-old pseudophakic man with a history of congenital iris coloboma, myopia, retinal tears, and a branch retinal vein occlusion with subsequent cystoid macular edema resistant to anti-VEGF medications but responsive to corticosteroids. He presented with sudden painless decreased vision in his left eye, 8 weeks following dexamethasone implant (Ozurdex) injection to the same eye. Upon presentation, he was diagnosed with corneal edema caused by anterior chamber migration of the implant. He was referred for immediate surgical intervention to extract the implant, with a resolution of the corneal edema within 2 weeks postoperatively. To conclude, this is the first case that reports Ozurdex implant migration through an iris coloboma in the setting of an intact posterior capsule. In addition, we describe a novel surgical approach for implant removal from the anterior chamber that is simple and efficient.