Capsular Tension Rings: Current Indications and Outcomes Maryam Mokhtarzadeh, MD Jayne S. Weiss, MD John M. Ramocki, MD No financial conflicts to disclose Kresge Eye Institute Detroit, Michigan

Background A CTR is a 270 degree open PMMA ring placed in the capsular bag during cataract surgery in cases with zonular instability or weakness. CTRs were introduced in 1991, used in Europe since 1993, but were only approved by the U.S. FDA in late We asked: How has the introduction of CTRs changed the surgical experience at KEI?

Purpose To examine the history and use of capsular tension rings among surgeons at an academic center, specifically determining the indications and results.

Methods Retrospective chart review of all complex cataract surgeries from 1/2005 to 5/2007 at KEI, identified by billing code (66982) Review of operating room logs from 1/2003 to 9/2007 to account for every CTR used at KEI and the local VA since FDA approval. Comparison of all CTR cases to a control group consisting of all other complex cataract surgeries. The data was analyzed for uptake, indications, and outcomes of CTR use.

Results Use: The first CTR was implanted at KEI in 10/2004 In the control group, 11 surgeons performed 254 cases coded as complex cataract surgeries. In the experimental group, 8 of these surgeons performed 58 cataract surgeries using CTRs. The experimental group included every case using CTRs that has been performed in the history of the institutions studied.

Results Indications: The most commonly listed preoperative indications for CTR placement were trauma (22%) and pseudoexfoliation (17%). Additional indications: prior intraocular surgery, phacodonesis, subluxed lens, high myopia, phacomorphic glaucoma, and phacolytic glaucoma. One third of patients in the experimental group had no known preoperative indications for CTR placement.

Results Outcomes: 85% of control cases resulted in IOL placement in the bag compared to 74% of CTR cases. 11% of control cases required anterior vitrectomy compared to 27% of CTR cases. CTRs were most frequently placed immediately after completion of cortical removal However, in cases where anterior vitrectomy was performed, CTRs were more frequently placed during phacoemulsification There was a single incidence of posterior CTR dislocation postoperatively which was successfully removed by pars plana vitrectomy.

Results 85%74 % Control CTR Used Placement of IOL

Results

Results (con’t) Pre-Phaco Post-Phaco Post-IA Unknown Mid-Phaco Mid-IA Post-Lens Surgical Timing of CTR Use CTR+Anterior Vitrectomy CTR+No Anterior Vitrectomy

Discussion Recently experience with CTRs has been increasing rapidly; half of the cases in this study were performed between 1/2007-9/2007. In our patient population there are many preoperative indications for CTR placement, most common being trauma. CTRs are often implanted in cases with no known preoperative indications due to surgeon preference or intraoperative discovery of zonular instability. Review of surgical boarding forms and consents revealed that the decision to place CTRs is most often made intraoperatively.

Discussion Most CTRs are placed immediately after removal of cortex is complete. However, in cases requiring anterior vitrectomy, CTRs are more often placed during phacoemulsification. There was a higher incidence of anterior vitrectomy in the experimental group. However, there was no statistically significant difference between the percentages of cases where an IOL could be successfully placed in the capsular bag. CTRs are being used effectively in difficult cases.