Swab Pressing vs Stromal Hydration to Prevent Incision Leakage and Transient Collapse of Anterior Chamber in Phacoemulsification: A Randomized Clinical Trial

Importance: During phacoemulsification, incision leakage and the subsequent anterior chamber collapse often occur after the withdrawal of the handpiece, which cannot be prevented by current sealing techniques. A new technique called swab pressing is proposed here to apply pressure with a cotton swab to seal the incision immediately, but efficacy remains unknown. Objective: To determine if swab pressing is noninferior to stromal hydration, the current practice, in sealing incisions in phacoemulsification for age-related cataract. Design, Setting, and Participants: This noninferiority randomized controlled clinical trial was conducted between February 2022 and September 2022 at the Zhongshan Ophthalmic Center, Guangzhou, China. Patients aged 60 to 90 years with age-related cataract were enrolled. Interventions: Participants were randomly assigned (1:1) to receive swab pressing or stromal hydration. All surgeries were performed by a single experienced surgeon who was unmasked to the assignment. Main Outcomes and Measures: The proportion of closed clear corneal incisions evaluated using intraoperative optical coherence tomography. Results: A total of 126 eyes of 126 participants were randomized into the swab pressing group (63 [50%]) and stromal hydration group (63 [50%]). The mean (SD) age of participants was 69.2 (6.14) years and 70.1 (7.67) years in the pressing and stromal hydration groups, respectively. A total of 39 participants (61.9%) in the pressing group and 35 (55.6%) in the modified group were female. The proportion of closed incisions was 96.8% (61 of 63) in the swab pressing group and 93.7% (59 of 63) in the stromal hydration group. Noninferiority was met, as the lower 95% CI of -5.83 percentage points was greater than the prescribed noninferiority margin of -6.60 percentage points (difference, 3.17 percentage points; 95% CI, -5.83 to 12.18 percentage points). The rate of anterior chamber collapse (pressing: 0 of 63 vs stromal hydration: 35 of 63 [55.6%]; P <.001) was lower in the swab pressing group. There were no differences between the 2 groups in the proportion of closed incisions and central anterior chamber depth at postoperative hour 1 and day 1. Conclusions and Relevance: In this study, swab pressing was noninferior to stromal hydration in sealing clear corneal incisions in phacoemulsification for age-related cataract. While this trial involved only 1 surgeon who was not masked to the interventions, the results suggest that swab pressing is feasible and further investigations would be warranted to determine if it prevents the intraoperative transient collapse of anterior chamber or affects visual acuity outcomes. Trial Registration: ClinicalTrials.gov Identifier: NCT05242653.