Surgically induced anterior, posterior, and total corneal astigmatism

Session Details

Session Title: Corneal Astigmatism Assessment. Surgery Equipment

Session Date/Time: Saturday 05/09/2015 | 11:00-13:00

Paper Time: 12:04

Venue: Main Auditorium

First Author: : P.Jeppesen DENMARK

Co Author(s): :    J. Pedersen   T. Olsen   K. Naeser              

Abstract Details

Purpose:

To evaluate the surgically induced astigmatism (SIA) from the anterior and posterior corneal surfaces after phacoemulsification through superior scleral incisions.

Setting:

Dept. of Ophthalmology, Aarhus University Hospital, Denmark

Methods:

Eighty eyes from 51 patients were measured with Nidek autorefractor and Pentacam preoperatively and one month postoperatively. All patients were operated using a 2.2 mm superior scleral incision. They were divided into with with-the-rule astigmatism (WTR) (36 eyes) and with against-the-rule astigmatism (ATR) (38 eyes). SIA was calculated from three methods. A) Using the K-readings from the Nidek autorefractor. B) Using the Pentacam K readings from the anterior and posterior corneal surface in a thick lens formula. C) Using the total refractive power from the Pentacam. The astigmatism was separate into polar values in 90 and 135 degrees.

Results:

The average SIA for the ATR group in polar values [D] (KP90,KP135, method) was (-0.05,-0.11, A), (-0.15, -0.13, B), and (-0.20, -0.13, C) and for the WTR group it was (-0.21, -0.11, A), (-0.08, -0.23, B), and (0.07, -0.17, C). No significant difference was found between the three sets of data for the group of ATR using polar values 90 (p=0.68) and 135 (p=0.99) or for the group of WTR using polar values 90 (p=0.10) and 135 (p=0.69)

Conclusions:

A small scleral incision induced minimal astigmatism irrespectively of the three different methods to measure the SIA.

Financial Interest:

NONE