Abstract
Purpose:
1) To evaluate the association between phakic status and the risk of postoperative cystoid macular edema (CME) after implantation of Boston Keratoprosthesis Type I (Kpro). 2) To evaluate the association between iris-backplate touch (IBPT) on anterior segment optical coherence tomography (ASOCT) and the risk of postoperative CME after Kpro.
Methods:
Retrospective non-interventional chart review. All patients who underwent Kpro type I implantation at the Illinois Eye and Ear Infirmary from 2007-2012 were reviewed. Patients were included in the study if they had at least one postoperative macular OCT and one postoperative ASOCT. Patients were excluded for poor quality images and aniridia. For all patients who met inclusion criteria, data were obtained including phakic status, pre-op and post-op visual acuity, time to final follow up, presence of CME on macular OCT and presence of IBPT on ASOCT. Two-tailed Fisher’s exact test was then performed to evaluate the statistical significance of phakic status and IBPT on postoperative CME.
Results:
One hundred and three Kpro were implanted into 95 eyes of 94 patients over a 5 year period. Fifty-eight eyes met inclusion criteria. Seven eyes were excluded for poor image quality and aniridia. Of the remaining 51 eyes, 21 (41.1%) had CME on postoperative macular OCT and 9 (17.6%) were pseudophakic. On Fisher’s Exact Test there was a statistically significant positive correlation between implantation of pseudophakic-type keratoprosthesis and presence of postoperative CME (p = 0.023). On review of ASOCT, 23 (45.1%) had evidence of IBPT. There was no significant correlation found between IBPT and postoperative CME on Fisher’s exact test (p = 0.167).
Conclusions:
CME is a frequent postoperative complication after Kpro implantation and can contribute to poor visual acuity outcomes. Patients with pseudophakic Kpros may be at higher risk for postoperative CME. Although IBPT may be a source of chronic inflammation in these patients, its presence on ASOCT is not a risk factor for postoperative CME.
Keywords: 575 keratoprostheses •
585 macula/fovea •
571 iris