Posters

Analysis of corneal astigmatism and other biometry parameters in consecutive cataract surgery candidates

Poster Details

First Author: I. Casal PORTUGAL

Co Author(s):    S. Monteiro   C. Abreu   V. Lages   P. Meneres           

Abstract Details

Purpose:

To analyse biometry data especially corneal astigmatism pattern in consecutive cataract surgery candidates.

Setting:

Department of Ophtalmology of a tertiary referral centre in Oporto, Portugal – Centro Hospitalar do Porto

Methods:

Biometry data measured by IOL master system® were colleted and analyzed in consecutive patients enrolled for cataract surgery in 1 month. We’ve analyzed the axial length(AL), anterior chamber depth(ACD), corneal powe (keratometry, flat K and steep K) and corneal astigmatism. We considered with-the-rule(WTR) astigmatism when the axis of the correcting negative cylinder was within 180 ± 30 degrees; against-the-rule(ATR) astigmatism when the axis of the correcting negative cylinder was within 90 ± 30 degrees; and oblique astigmatism if it was neither WTR nor ATR. Patients with corneal disease, history of ocular trauma or previous corneal surgery were excluded.

Results:

322 eyes were included(60,9 %female).Mean age was 71,5±9,9 years. Mean values of AL,ACD,K1,K2 and corneal astigmatism were 23,5±1,6; 3,05±0,41 ; 43,5±1,6 ; 44,5±1,7 and 1,04± 0,75,respectively. Corneal astigmatism was<0,50 Diopters(D) in 23,3% of the eyes;0,50-0,99 D in 32,9%;1,00-1,49 in 23,9% and ≥1,50 D in 19,9%. 41,9% had WTR astigmatism,39,1% ATR astigmatism and 18,9% oblique astigmatism.We observed increasing frequency of ATR astigmatism with age,resulting in a statistically significant higher median age in ATR astigmatism group(p = 0.038). In the< 50 year-old group only 21,4% had ATR astigmatism while in the>80 year-old group 41,9% had ATR astigmatism. The opposite was found with WTR astigmatism- in the<50 year-old group 64,3% had WTR astigmatism while the same value in the>80 year-old group was 39,2%.

Conclusions:

In our population the astigmatism axis was predominantly WTR, the frequency of ATR astigmatism increased with age and we found a significant percentage of 1,50 D or higher corneal astigmatism. These ocular biometric data can contribute to a better understanding of the astigmatism pattern in cataract surgery candidates as well as improve surgical procedures.

Financial Disclosure:

NONE