A prospective, randomised study of the effect of fixation sutures during phacotrabeculectomy on intraocular pressure and incidence of ptosis

Abstract

We investigated the effects of different intraoperative eyeball fixation techniques (superior rectus muscle suture [MS] and traction suture at the corneal limbus [CS]), on intraocular pressure (IOP) and the incidence of ptosis after phacotrabeculectomy. Forty-one eyes with different glaucoma types which qualified for phacotrabeculectomy were included. Twenty-three and eighteen patients were included in the CS and MS groups, respectively. The IOP, best-corrected visual acuity (BCVA), and margin reflex distance were assessed preoperatively and 3, 6, and 12 months post-operatively. Preoperatively, the mean IOPs (± standard deviation) in the CS and MS groups were 23.6 ± 7.3 mmHg and 24.3 ± 6.6 mmHg (p > 0.05), respectively. At 3 and 6 months post-surgery, the mean IOPs were significantly lower in the CS group than in the MS group: 13.9 ± 3.0 mmHg vs. 17.7 ± 3.5 mmHg (p = 0.001), and 13.9 ± 4.9 mmHg vs. 17.2 ± 3.5 mmHg (p = 0.005), respectively (mean difference: 3.9, 95% confidence interval 1.7–6.1). At 12 months, the mean postoperative IOPs were 15.2 ± 3.5 mmHg and 14.9 ± 3.6 mmHg in the CS and MS groups, respectively (p > 0.05). At 6 months, the BCVAs were 0.91 ± 0.15 and 0.71 ± 0.3 (p = 0.029) in the CS and MS groups, respectively; BCVAs were 0.91 ± 0.15 and 0.71 ± 0.3 (p = 0.029) in the CS and MS groups, respectively; the difference was non-significant 12 months post-surgery (0.78 ± 0.32 vs. 0.74 ± 0.30, p = 0.553). Postoperative ptosis was observed in 4 (17%) and zero patients in the CS and MS groups, respectively, but the difference was not statistically significant (p = 0.118). The study was not powered sufficiently to detect statistically significant changes in exploratory endpoints. The study was not powered sufficiently to detect statistically significant differences between groups in exploratory endpoints.