Ultrastructure of clear corneal incisions - Part II: Corneal trauma after lens implantation with the Microstaar injector system

Purpose: To examine the ultrastructure of clear corneal incisions (CCls) after implantation of a plate-haptic intraocular lens (IOL) with the Microstaar(TM) injector system through two incision widths. Setting: University Eye Clinic and Institute of Histology and Embryology II, University of Vienna, Austria. Methods: Fourteen human cadaver eyes without prior ocular surgery were obtained from the University Eye Bank, Vienna. Single-plane CCls were performed with 3.0 and 3.2 mm steel keratomes. Using the Microstaar injector system, a foldable silicone plate-haptic IOL (23 diopters) was implanted in the anterior chamber. ;During the entire procedure, the eye pressure was kept between 26 and 30 mm Hg by infusing balanced salt solution into the anterior chamber. Specimens for light microscopy and scanning electron microscopy were prepared according to standard procedures. Results: After IOL implantation, the 3.0 mm steel blade incisions exhibited distinct distensions at their lateral ends. Adjacent to these distensions, the collagen lamellae were pressed apart, displaced, and torr. in 3.2 mm tunnels, the corneal trauma at both lateral ends was considerably less severe. These incisions also showed a better primary adaptation of the wound lips after implantation. Conclusions: implantation performed with the Microstaar injector system through 3.0 mm steel blade CCls led to considerably more severe corneal trauma than implantation through 3.2 mm incisions.