Clinical Manifestations and Risk Factors of Anterior Chamber Migration of a Dexamethasone Implant

ABSTRACT

Purpose@#To investigate the clinical features, risk factors, and treatment outcomes for anterior chamber migration of an intravitreal dexamethasone implant (Ozurdex®; Allergan Inc., Irvine, CA, USA). @*Methods@#We retrospectively reviewed the medical records of patients who were diagnosed with anterior chamber Ozurdex® migration. Prior surgical histories were obtained and comprehensive ophthalmic examinations were conducted for all eyes. Treatment strategies and outcomes were also analyzed. @*Results@#Among 1,276 intravitreal Ozurdex® injections, anterior migration occurred in six eyes of six patients (0.47%). All six eyes were pseudophakic, and they had undergone prior vitrectomies. The vitrectomized pseudophakic eyes, in contrast to the nonvitrectomized pseudophakic eyes, were significantly associated with an increased risk of anterior chamber migration (odds ratio [OR] = 19.2, p = 0.009). Moreover, the vitrectomized eyes with reduced zonular/capsular bag complex integrity, in contrast to the vitrectomized eyes with intact zonular/capsular bag complex integrity, were significantly associated with an increased risk of anterior chamber migration (OR = 50.2, p < 0.001). All six eyes underwent surgical intervention one eye with a repositioning procedure, and the other five eyes with surgical removal of the implant. Corneal edema was resolved within two months after surgery; however, one patient eventually developed corneal endothelial dysfunction. @*Conclusions@#Prior vitrectomy and a defective lens capsule or weak zonules/zonular dehiscence are risk factors for anterior chamber Ozurdex® migration; thus, caution is recommended in these patients. Urgent removal of the implant should be considered when anterior migration of the implant is diagnosed with corneal edema.