Manipulation of the iris in extracapsular lens extraction.

Successful extracapsular cataract surgery depends on adequate mydriasis, which will facilitate the anterior capsulotomy and provide a full field of view throughout the operation. The surgeon, especially the neophyte, must recognise which irises may present a difficulty in establishing, maintaining, and reversing mydriasis, with or without the introduction of an intraocular lens. The author describes the preliminary assessment of the iris for disease, previous iris surgery, ease of dilatation, and the place of primary iridectomy. Topical and subconjunctival preoperative mydriatics are assessed, and a practical account of the pharmacological, mechanical, and surgical means of maintaining intra-operative mydriasis is given. The indication for iridectomy in extracapsular lens extraction with or without an intraocular lens is reviewed, and the postoperative manipulation of the iris is described with reference to the problems caused by rebound mydriasis.