Purpose: To compare the visual outcomes, rate of cystoid macular edema (CME), and additional associated complications in eyes that exhibited zonular dialysis (ZD) during phacoemulsification to a reference group of uneventful phacoemulsification eyes.
Methods: A retrospective multicenter comparative database study. We pooled data from 8 United Kingdom sites between 2003 and 2015. The main outcome measures were the mean postoperative visual acuity (VA) at 12-24 weeks and the rates of CME and additional associated complications.
Results: We included 1074 eyes in the ZD group and 112,479 in the reference group. Logistic regression analysis showed that pseudoexfoliation was the strongest associated factor of ZD (OR: 6.1), followed by previous glaucoma surgery (OR: 4.4). Mean logMAR preoperative VA was 0.8 ± 0.6 in the ZD group vs. 0.6 ± 0.5 in the reference group (p < 0.001). Mean postoperative VA was worse in the ZD group (p < 0.001); 0.4 ± 0.6 vs. 0.2 ± 0.3 and 0.5 ± 0.6 vs. 0.2 ± 0.3 at 4-12 weeks and 12-24 weeks, respectively. At 12-24 weeks, the proportions of eyes that gained ≥0.3 logMAR units were 50% in the ZD group vs. 62% in the reference group (p < 0.001). In the ZD group, the most common intraoperative complication was vitreous loss (34.3%), followed by posterior capsular rupture (PCR) (11.1%). Postoperative CME occurred in 2.3% vs. 1.4% (p = 0.01), and 9.3% of eyes required surgery for correction of aphakia, intraocular lens decentration, or dropped lens figments removal.
Conclusions: The occurrence of ZD was associated with worse postoperative vision, an increased rate of vitreous loss and PCR, and a higher risk of CME.
Keywords: Cataract; choroidal hemorrhage; phacoemulsification; posterior capsular rupture; zonular dialysis.