[A distance ring for stabilization of the lens capsule (a multicenter clinical study)]

Cataract extraction in eyes with a loose suspension apparatus implies always an unconventional method of surgery. An important contribution towards the stabilization of the capsule during surgery and during the postoperative period is implantation of a polymethyl methacrylate (PMMA) ring into the capsular bag during phacoemulsification and implantation of the lens in patients with dialysis of the zonula. Erilens Co. produced three types of distance rings which were tested in 1997 within the framework of a multicentre clinical trial in seven departments in the Czech Republic: the most frequent indication for implantation of a distance ring was subluxation of the lens in 16 eyes, instability of the capsule in patients with myopia in nine eyes, traumatic cataract after contusion in five eyes and after a perforating injury in five eyes. In two patients the ring was used during normal cataract extraction when during aspiration of the lenticular mass the zonula loosened. From the total number of 47 distance rings it proved possible to implant primarily into the capsule only 42, two further rings were implanted primarily into the sulcus and left there. In patients with ectopia of the lens the ring was fixed into the sulcus ciliaris. In two instances the ring was explanted during the operation on account of instability of its position, in one instance the ring was damaged during implantation. The type and frequency of complications during and after surgery corresponded to the patient's pathology before the operation. More than three quarters of the operated eyes had after operation corrected vision better than 6/18. Poorer vision after surgery in nine patients was due to age-related or post-traumatic changes on the fundus. The results of the multicentre clinical trial evaluating the implantation of the distance ring of Erilens Co. conducted in seven departments of the Czech Republic in 1997 provided evidence that the quality of these rings is comparable with types produced abroad and used in complicated surgery of the anterior segmental of the eye.