Variations in intraocular lens injector dimensions and corneal incision architecture after cataract surgery

Purpose: To evaluate the differences in intraocular lens (IOL) injectors and to assess the effect of IOL insertion on injector tips and eyes after cataract surgery in a rabbit model.

Setting: Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, Florida, USA.

Design: Experimental study.

Methods: A modified optical comparator was used to measure the tips of 13 IOL injector models to determine the perimeter, tip angle, and cone angle of each. Injectors were analyzed before and after IOL insertion. Surgery was performed on rabbits with 71 IOL injectors of 13 models, and custom gauges were used to determine the incision size before and after surgery.

Results: The injector dimensions varied by model; tip diameter, tip angle, and cone angle ranged from 1.44 to 2.12 mm, 29.7 to 66.5 degrees and 0.6 to 10.8 degrees, respectively. The incision size through which surgery was successfully performed also varied by injector model; the initial incision sizes ranged from 2.0 to 2.63 mm. For all injectors, there was wound enlargement after IOL insertion that ranged from a 0.1 to 0.65 mm increase in incision length.

Conclusions: The dimensions and injection systems varied with each IOL injector. All injectors led to postoperative wound stretch after IOL insertion, with no final incision measuring less than 2.0 mm. These findings suggest that the clear cornea incision should have a width corresponding to the injector diameter.