Corneal refractive changes after acrysof lens versus PMMA lens implantation

Do foldable acrylic lenses yield not only reduced posterior capsular opacification but also significant refractive advantages?

147 cataract patients including 47 with spherical corneas and 100 with preoperative astigmatism of 0.8 +/- 0. 7 dpt were treated in one of two ways: 70 patients received 5.5-mm Acrysof lens implants through 3.2-mm outer and 4-mm inner temporal clear corneal openings (stretch incision); 77 patients received 5-mm PMMA lenses through temporal clear corneal incisions of 4.1-mm outer and 6.5-mm inner diameter incisions. Corneal topography was examined in all patients before the operations as well as 3 days and 6 months after the operations.

6 months after the operations, we observed a surgically induced astigmatism of 0.4 +/- 0.2 dpt for the 3.2-mm incisions compared to 0.8 +/- 0.7 dpt for the 4.1-mm incisions; evaluation according to Holladay of the preoperative spherical corneas yielded a with-the-wound change of 0.0 +/- 0.3 dpt after 3.2-mm incisions versus 0.6 +/- 0.7 dpt after 4.1-mm incisions. The difference in astigmatism for the two types of incisions was statistically significant (p = 0.001).

Acrysof lens implantation is especially useful for patients with spherical corneas because of avoidance of postoperative astigmatism. The 4. 1-mm corneal incision using PMMA lens implants can be used on the steep meridian to reduce preoperative astigmatism.