Rate of cataract formation in 343 highly myopic eyes after implantation of three types of phakic intraocular lenses.

PURPOSE To assess the feasibility of using phakic intraocular lenses (PIOL) to treat high myopia, and evaluate the incidence of cataract, comparing three different lens types. METHODS From 1989 to 2002, we implanted three different phakic intraocular lenses (PIOL) in 343 eyes of 232 patients; 231 eyes recieved an Ophtec (Worst-Fechner model, iris-claw), 89 an Adatomed (silicone posterior chamber), and 23 a Staar (posterior chamber, models V2, V3, V4). Average follow-up was 96.2 months for the Ophtec group, 31.5 months for the Adatomed group, and 19.3 months for Staar group. Eyes that subsequently developed cataract were studied for clinical evolution and had PIOL explantation and cataract extraction. RESULTS Nuclear cataract developed in 7 of 231 eyes (3.04 %) with an Ophtec lens. Anterior subcapsular cataract developed with the two types of posterior PIOLs (Adatomed group: 38/89 eyes, 42.69%; Staar group: 3/23 eyes, 13.04%). Anterior subcapsular cataract in the Adatomed group developed more rapidly compared to the Staar group. We explanted 7 lenses in the Ophtec group, 16 lenses in the Adatomed group, and 2 lenses in the Staar group (models V2 and V3 only). Patient age older than 40 years at implantation of PIOLs and axial length greater than 30 mm were factors significantly related to nuclear cataract formation and the Ophtec lens. However, these two factors had a weaker correlation with the posterior phakic lenses (Adatomed, Staar) for high myopia than with the Ophtec lens. Postoperative best spectacle-corrected visual acuity remained stable after explantation, phacoemulsification, and posterior chamber lens implantation. CONCLUSIONS Delayed cataract development and cataract type (nuclear) in patients with an Ophtec lens and the variables of patient age (>40 yr) and axial length (>30 mm) may considered prognostic factors. Other factors such as lens design, material, and placement probably influenced cataract formation in patients with the Adatomed and Staar PIOLs. The lens styles used in this study are no longer manufactured.