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.

Anterior migration of Ozurdex implant: a review on risk factors, complications, and management

“…However some other approaches prioritize minimization of contact between instruments and the implant in order to reduce the chance of breaking it into fragments [ 12 ]. These include use of BSS to direct flow through a corneal incision and out of the AC [ 4 , 10 ] and similarly a no-touch technique using viscoelastic to allow implant egression. In this no-touch technique, a corneal incision is made and the implant is positioned parallel to the incision’s axis.…”

Dexamethasone implant migration in an eye with congenital glaucoma: A case report and review of the literature

“…This finding led the authors to conclude that a lens capsule defect or a history of PPV increases the chance of AC migration. Pseudophakia, 6–10 including posterior chamber intraocular lenses (PCIOL), anterior chamber intraocular lenses (ACIOL), 11,12 sulcus intraocular lenses, iris-fixated lenses, 5–7,13,14 scleral-fixated lenses, 12,15–19 and glued IOLs, 20 have all been reported in cases of implant migration. Aphakia, 5,21–26 prior iridectomies, 6,12,20,26,27 congenital iris coloboma, 10 posterior capsule violation during prior surgeries or following posterior capsulotomies, 5,7,13,27 and weak zonules 9,28 are other features frequently noted in these cases.…”

“…Pseudophakia, 6–10 including posterior chamber intraocular lenses (PCIOL), anterior chamber intraocular lenses (ACIOL), 11,12 sulcus intraocular lenses, iris-fixated lenses, 5–7,13,14 scleral-fixated lenses, 12,15–19 and glued IOLs, 20 have all been reported in cases of implant migration. Aphakia, 5,21–26 prior iridectomies, 6,12,20,26,27 congenital iris coloboma, 10 posterior capsule violation during prior surgeries or following posterior capsulotomies, 5,7,13,27 and weak zonules 9,28 are other features frequently noted in these cases. Other alterations to the natural lens or iris anatomy may place patients at higher risk of implant migration due to the presence of additional pathways for the implant to travel.…”