Surgically induced astigmatism following a 4.0 mm sclerocorneal valve incision.
OBJECTIVE
To determine whether sutureless small incision cataract surgery reduces induced astigmatism over the long term.


METHODS
University Eye Hospital, Vienna, Austria.


METHODS
In a prospective study, we investigated surgically induced astigmatism in 63 cases of no-stitch, small incision cataract surgery with a 4.0 mm square sclerocorneal tunnel and implantation of a flexible intraocular lens. Follow-up was 4 to 5 years. Keratometry was measured with a Zeiss keratometer preoperatively and after 1 day, 1 week, 1, 3, and 9 months, and a median of 4.4 years. In 21 nonoperated eyes, we investigated the natural course of astigmatism over 5 years.


RESULTS
The mean keratometric cylinder stabilized at 0.8 diopter (D) after 1 week and slightly decreased to 1.0 D after 4 to 5 years. Cravy's vector analysis showed an immediate against-the-rule (ATR) shift of -0.2 D that remained relatively stable until 9 months. Between 9 months and 4.4 years postoperatively, there was a statistically significant increase in ATR induced astigmatism from -0.2 to -0.5 D. The natural course of astigmatism in the nonoperated eyes showed an ATR shift of -0.1 D for the same period.


CONCLUSIONS
The result show a small, though statistically significant amount of postoperatively induced astigmatism 4 to 5 years after no-stitch, small incision cataract surgery.
Rainer
G
G
University Eye Hospital, Vienna, Austria.
Menapace
R
R
Vass
C
C
Strenn
K
K
Papapanos
P
P
D000368:Aged; D001251:Astigmatism / Q000209:etiology* / Q000473:pathology; D002387:Cataract Extraction / Q000009:adverse effects* / Q000379:methods; D003315:Cornea / Q000473:pathology / Q000601:surgery*; D005500:Follow-Up Studies; D006801:Humans; D011183:Postoperative Complications; D011446:Prospective Studies; D012590:Sclera / Q000601:surgery*; D013536:Suture Techniques; D013997:Time Factors; D014792:Visual Acuity