Microscopic analysis of preinsertion cutting modalities on custom, flexible iris prostheses

Abstract

Purpose: To determine the induced edge effects of different clinically used device postmanufacture modification styles and modalities on custom iris implants. Settings: An academically affiliated multispecialty private practice group and an academic medical center. Design: Laboratory study. Methods: Sample custom iris prostheses were cut using patterns, blades, and surgical instruments described in the literature. The cut edges were evaluated with slitlamp microscopy, light microscopy, and scanning electron microscopy. Results: Disposable blades yielded smoother cuts than scissors. Trephine blade brand significantly affected the cut surface smoothness of the silicone matrix. Meshwork-embedded prostheses had some irregular sharp edges where the mesh fibers were cut with all modalities, although these were worse with scissors and one tested trephine brand compared with the other. Pseudoiridectomies and scissor cuts created sharp points and corners in the device periphery. Conclusions: Postmanufacture modifications of iris implants should be minimized. The cut margins of the fiber-free implants have fewer sharp edges and may be preferable for sulcus placement. In-the-bag device placement may mitigate clinical impact of sharp edges and corners. These practices may help to minimize inflammatory sequelae postimplantation.