Astigmatism outcomes of horizontal temporal versus nasal clear corneal incision cataract surgery

J Cataract Refract Surg. 2004 Feb;30(2):418-23. doi: 10.1016/S0886-3350(03)00492-9.


Purpose: To compare the short- and long-term astigmatism outcomes after cataract surgery using temporal clear horizontal corneal incisions and nasal horizontal clear corneal incisions.

Setting: Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, Maryland, USA.

Methods: This retrospective study included a consecutive series of eyes having phacoemulsification with implantation of a 6.0 mm foldable acrylic intraocular lens through a 3.5 mm horizontal clear corneal incision at 180 degrees (temporal incision in right eyes, nasal incision in left eyes). Astigmatism was measured by keratometry readings before surgery and 6 weeks and 12 months postoperatively.

Results: The mean preoperative astigmatism in the 178 eyes (94 right, 84 left) of 161 patients was 0.78 diopter (D); 54.5% of eyes had against-the-rule (ATR) astigmatism, 22.5% had with-the-rule (WTR) astigmatism, and 14.0% were astigmatically neutral. A significant shift toward WTR astigmatism occurred postoperatively. At 6 weeks, 48.3% of eyes had WTR astigmatism and 23.0% had ATR astigmatism. At 12 months, 43.8% had WTR astigmatism and 25.8% had ATR astigmatism. Vector analysis revealed a mean surgically induced astigmatism (SIA) of 1.17 D at 6 weeks and 1.04 D at 12 months. The side of the incision significantly affected SIA. At 6 weeks, temporal incisions yielded a mean SIA of 0.74 D and the nasal incisions, of 1.65 D. This trend in SIA persisted at 12 months: 0.71 D for temporal incisions and 1.41 D for nasal incisions.

Conclusions: Cataract surgery using a horizontal clear corneal incision induced WTR astigmatism 6 weeks and 12 months postoperatively. Temporal incisions induced significantly less astigmatism than nasal incisions.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Astigmatism / physiopathology
  • Astigmatism / prevention & control*
  • Cornea / physiopathology
  • Cornea / surgery*
  • Female
  • Humans
  • Lens Implantation, Intraocular / methods*
  • Male
  • Middle Aged
  • Minimally Invasive Surgical Procedures
  • Phacoemulsification / methods*
  • Postoperative Complications / prevention & control
  • Refraction, Ocular
  • Retrospective Studies
  • Visual Acuity