Correcting postoperative astigmatism using curved lamellating keratotomy.

PURPOSE

To ascertain whether the change in refraction caused by paired lamellating corneal incisions in cadaver eyes could be achieved in living eyes and whether wound healing influences this effect.

SETTING

Virchow Hospital Eye Clinic, Humboldt University, Berlin, Germany.

METHODS

This prospective study included 45 patients who had a follow-up of 15 months. All had astigmatism of at least 2.00 diopters (D) induced by previous cataract surgery. Optical zones of 7.0 and 8.0 mm and chordal lengths of 3.0 and 5.0 mm were used. All incisions were paired.

RESULTS

Mean preoperative astigmatism measured with a keratometer was 3.64 D +/- 0.89 (SD). After 15 months, it was 1.00 +/- 0.76 D, and mean induced astigmatism was 3.18 +/- 1.30 D. The 7.0 mm group had a mean induced astigmatism of 3.93 +/- 1.52 D, which was significantly higher than that in the 8.0 mm group (mean 2.60 +/- 0.74 D) at a uniform chordal length of 3.0 mm. Mean uncorrected visual acuity was 0.26 +/- 0.14 preoperatively and 0.50 +/- 0.28 after 15 months; mean corrected visual acuity improved from 0.58 +/- 0.21 to 0.76 +/- 0.21. Mean endothelial cell count was 1799 +/- 595 cells/mm2 preoperatively and 1784 +/- 589 cells/mm2 after 6 months; the difference was not significant.

CONCLUSION

Curved lamellating keratotomy gives stable postoperative refractive results without significantly affecting endothelial cell count or visual acuity.