Safety Profile of Venturi Versus Peristaltic Phacoemulsification Pumps in Cataract Surgery Using a Capsular Surrogate for the Human Lens

Abstract

Purpose: To compare the risk of capsular rupture of the human lens during cataract surgery from contact by phacoemulsification needles using different vacuum pumps, ultrasound modalities, and contact angles.

Design: Experimental laboratory investigation.

Methods: The John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, was the setting for this study. A Signature (Abbott Medical Optics, Inc) phacoemulsification machine was used in peristaltic and Venturi vacuum modes with transversal and micropulsed ultrasound. Contact was made with a capsular surrogate to achieve tip occlusion or tip contact only. Breakage rates were calculated by analyzing the capsular surrogate under a surgical microscope.

Results: Venturi and peristaltic pump modes had similar risk of capsular rupture, regardless of whether the data were analyzed with tip occlusion data included (44.2% peristaltic vs 40.2% Venturi, P = .047) or excluded from the analysis (66.3% peristaltic vs 60.3% Venturi, P = .013). Transversal ultrasound was significantly more likely to cause capsular rupture than micropulsed ultrasound (69.8% vs 56.8%, P < .0001). Tip contact was significantly more likely than tip occlusion to cause capsular rupture (63.3% vs 0%, P < .0001).

Conclusions: There is no significant difference in risk of capsular rupture using Venturi rather than peristaltic vacuum pumps, while transversal seemed to increase the risk when compared to micropulsed ultrasound. Tip occlusion is not a risk factor for capsular rupture, as all breaks in the capsular surrogate occurred with tip contact.