Scleral fixation posterior chamber intraocular lens (IOL): Research for a more stable implant

Purpose. To design and test a new IOL purposely conceived for scleral fixation in the posterior chamber for cases lacking an adequate support by the posterior capsule and zonule. Methods. We designed an IOL with the following characteristics: a) 14 mm. in length; b) polymethylmetacrylate material; c)7mm. in diameter plano-convex optic; d) two C-shaped "haptics"; e) two opposite "processes" with a ring (2.5 mm. in length) placed at 90° from the middle point of the haptics. The rings are passed through by the scleral sutures. Prototypes were made by the SOLEKO firm in Italy. After cataract extraction, we implanted the IOL in 21 cases lacking adequate capsular and/or zonular support for ordinary posterior chamber implantation (posterior capsule breaks, intracapsular/total cataract extractions, vitrectomized eyes, subluxations of the lens, luxation of IOL). Results. In 20 eyes the IOL remained centered and on a frontal plane for at least a six months' follow up. One eye, operated on for retinal detachment and intracapsular cataract extraction, required the further suturing of one "haptic" to take care of a tilting. Limited haemorrhage was observed at the time of the sulcus suturing. Conclusions. We believe that the four supports of this IOL make it one of the stablest designs conceived. The dimensions of the "processes" make the IOL easily centered and stable. After some practice implantation of this IOL is easily accomplished. However, due to the large overall dimensions of the IOL a correct surgical technique must be learned.