Secondary evaluation of hydrogel lens implants

Abstract

Objective: To review patients currently forming part of a study of poly 2 hydroxyethylmethacrylate (P-HEMA) 'Hydrogel' intraocular lenses.

Design: Patients were taking part in the Hydrogel arm of a prospective trial at Scarborough Hospital. Recruitment was by letter.

Setting: District General Hospital.

Patients: One hundred and eight from the Scarborough trial in whom a Hydrogel lens had been implanted.

Interventions: An independent assessment was carried out at a median interval of 20 months following surgery. Visual acuities were assessed with best possible refraction and the eyes examined both before and after pupil dilation.

Main outcome measures: Visual acuity and major complications.

Results: 91% had visual acuities of 6/9 or better and 30% achieved 6/5. In 61% the central area (3 mm diameter) of posterior capsule was clear but 39% had significant fibrosis or pearl formation in this area and 8% had undergone posterior capsulotomy. Five major decentrations had taken place, one of which occurred following a spontaneous rupture of the posterior capsule 17.6% of patients showed significant pigment dispersion behind the IOL either on the posterior capsule or in the anterior vitreous that could not be accounted for purely by surgical trauma. An atonic iris sphincter was noted in 17% of eyes.

Conclusions: This lens gives good visual results but its stability and tendency to cause pigment shedding need to be closely monitored.