[Prospective study of cataract after 5 years intraocular lenses with and without laser ridge]

A prospective randomized study was carried out to investigate whether intraocular lenses with and without laser ridge have different effects on the development of secondary cataract.

An extracapsular cataract extraction with implantation of a posterior chamber lens was carried out in the period from November 1986 to March 1987 in 100 patients (100 eyes). The first group of 50 patients (50 eyes) received a convex-plane (plano-posterior) intraocular lens (IOL) with a continuous 360 degrees-laser ridge. The second group of 50 patients (50 eyes) received a convex-plane (plano-posterior) IOL without laser ridge. The follow-up investigations were carried out after 10 days, 2 months, 6 months and 1, 2, 3, 4 and 5 years. Parameters such as the state of intraocular irritation, the intraocular pressure and astigmatism were also registered during the first six months after the operation. Attention was paid to the opacity of the posterior capsule and the deterioration in visual acuity associated with this in the subsequent investigations 1, 2, 3, 4 and 5 years after the operation. All cases with a deterioration of vision by two lines caused by an opacity of the posterior capsule were evaluated as secondary cataract.

On the basis of this classification, the rate of secondary cataract in the IOL group without laser ridge was 18.5%, as compared to 19.2% in the IOL group with laser ridge.

After 5 years there is no statistical significant difference between the two groups (Fishers-Exact-Test, p = 0.999).