Correction of Myopia by Implantation of Minus Optic (Worst Iris Claw) Lenses into the Anterior Chamber of Phakic Eyes

Abstract

OBJECTIVE: Critical report on the technique of operative correction of high myopia by implantation of a concave lens (Worst iris claw lens) into the phakic eye, its efficacy and risks. STUDY DESIGN: Prospective study of postoperative results. SETTING: The operations were performed at the Robert Koch Hospital, Hannover-Gehrden, the postoperative examinations at Dr Fechner's practice in Hannover, Germany. PATIENTS: 127 highly myopic eyes were implanted between November 1986 and November 1991. 123 eyes had a follow-up period of at least 6 months (mean 34.2, range 6 to 62 months). RESULTS: 84 of the 123 eyes (68.3%) were corrected within 1.00 dioptre of the desired refraction and only 10 eyes (8.1%) deviated more than 2 dioptres from the calculated correction. The anatomical results were excellent, being characterized by absence of glaucoma and inflammation and by good fixation of the lens. However, in eight of 118 eyes (6.8%) in which the endothelial density was high after operation the density decreased during the follow-up period. CONCLUSIONS: The concave Worst iris claw lens allows correction of high myopia. However, permanent inspection of the endothelial density at regular intervals throughout the life of the patient is required in order to recognize the need for removal of the lens in the event the endothelial density should decrease. This draw-back may be overcome by implanting a negative lens into the posterior chamber of the phakic eye.