The spectrum of iatrogenic intraocular injuries caused by inadvertent cannula release during anterior segment surgery

Abstract

Objective: To evaluate the causes of inadvertent intraocular injuries resulting from the use of cannulas during anterior segment surgery. Method Retrospective review of all cases with inadvertent release of irrigation and viscoelastic cannulas during anterior segment surgery in 15 years.

Results: Inadvertent release of cannulas occurred in 9 of 10 230 cases of anterior segment surgery during a 15-year period. The incidence of cannula release was 0.88 per 1000 procedures per year. Twenty percent of the surgeons who performed anterior segment surgery in this period were involved in this unfortunate event. Six cases occurred during cataract extraction and 3 during penetrating keratoplasty or replacement of corneal graft. The latter 3 cases included posterior capsule rupture and vitreous loss. Macular scar in 2 (22%) of the 9 cases was associated with poor visual outcome of counting fingers at 2.1 to 3.0 m (P = .03). In all other surgeries, the cannula caused iris or anterior chamber angle injury without consequences.

Conclusions: Inadvertent release of cannulas during anterior segment surgery is a rare, memorable, and unfortunate event. The severity of the injury may be related to the type of the surgical wound. In most cases, visual outcome is not compromised unless the cannula causes retinal disruption.