The effect of total ultrasound time, average ultrasonic power, and effective phacoemulsification time on post-operative outcomes in dogs undergoing phacoemulsification surgery

Abstract

Purpose: To investigate the relationship between UST (total ultrasound time), AVG (average ultrasonic power) and EPT (effective phacoemulsification time) with visual outcome and the most common surgery-related complications post phacoemulsification. Additionally to identify whether postoperative intraocular pressure (IOP) was significantly different between visual and non-visual eyes.

Methods: Medical records of patients undergoing phacoemulsification surgery between 2018 and 2024 were reviewed. Patients were included if UST, AVG and EPT were recorded, and data were available for six months postoperatively. Ultrasound time, AVG and EPT were compared with the number of postoperative complications, presence/absence of any complications and presence/absence of the most common individual complications at each timepoint. Additionally, EPT was compared in diabetic versus all other cataracts; a general linear mixed model approach was used for the statistical analysis. A permutation approach was used for analysis of IOPs by vision status.

Results: There was a significant relationship between higher number of complications and higher UST (p=0.017) and EPT (p=0.001) in the first week postoperatively. At one month postoperatively, there was no significant relationship between UST, AVG or EPT and the number of complications. However, when comparing dogs with and without complications, UST (p=0.032) and EPT (p=0.019) were significantly higher in eyes with complications. The non-visual eyes had significantly higher UST and EPT at the one and six months, respectively. Between the end of the first month and up to six months postoperatively 158 (86.4%) eyes were visual. At all time points, non-visual eyes had significantly higher IOP. Diabetic cataracts required significantly lower EPT.

Conclusion: Increases in UST and EPT are associated with higher numbers of complications at one week postoperatively. Eyes that developed complications at one month postoperatively are associated with higher UST and EPT.

Keywords: Canine; Effective time; Energy; Phacoemulsification.