Implantation of spheric phakic posterior chamber intraocular lenses in astigmatic eyes

To evaluate the simultaneous correction of spherical and cylindrical ametropia through implantation of phakic posterior chamber (PC) intraocular lenses (IOLs) combined with a limbal incision.

Eye Department, Schlosspark-Klinik, Charité University Berlin, Berlin, Germany.

In 5 hyperopic and 7 myopic eyes with varying astigmatic measurements, a refractive correction was achieved by implanting phakic PC IOLs (Staar Surgical Co.) and performing limbal incisions of different lengths. The incisions were placed approximately 1.0 mm from the limbus with a mean depth of 600 microm and a length of 6.0 mm +/- 0.9 (SD). The phakic PC IOLs were implanted after the limbal incisions were placed.

In the 5 hyperopic eyes, the astigmatism decreased from 2.7 diopters (D) preoperatively to 0.5 D at a mean of 7.5 +/- 1.7 months without alteration of the axis of highest bowing. In the 7 myopic eyes, it decreased from 2.2 D preoperatively to 0.7 D at 7.2 +/- 2.6 months. In 3 hyperopic eyes and 1 myopic eye, the limbal incisions were repeated.

The observed mean postoperative spherical equivalent was close to emmetropia. Repeat incisions were necessary in eyes exhibiting astigmatism greater than 2.5 D. The advantage of limbal incisions in combination with phakic PC IOL implantation is demonstrated not only by the astigmatic reduction but also by the axis stability. It will be interesting to see whether toric phakic lenses can achieve the same postoperative results, especially in axis stability and reduction of higher degrees of astigmatism.