Posters

A comparison of K readings using handheld and mounted autokeratometers in different settings

Poster Details

First Author: D.El Sayed EGYPT

Co Author(s):    M. El Nahrawy              

Abstract Details

Purpose:

To compare keratometry measurements by handheld Nidek ARK 30 and on table (mounted) Topcon KR8100 auto-K/autoref and evaluate the degree of agreement in the 2 instruments in different situations

Setting:

Alexandria University Hospital, Egypt

Methods:

The study included 100 patients (200 eyes) of adult patients undergoing cataract surgery under general anaesthesia. In the office, the K readings of both eyes of each patient were taken before surgery without dilatation using each of the 2 instruments. Anther group of readings was taken from the eyes to be operated after dilatation using both instruments. A third group of readings was taken for both eyes after the patients were anaesthetized using the hand held autokeratometer. Intraclass correlation coefficient for the average K readings was used to examine the agreement between the 2 instruments in every situation.

Results:

Two hundred eyes of 100 adult patients were enrolled in the study. The age of patients ranged from 20-75 with an average of 54.4±12.2. the average K readings in undilated pupils were 44.7±.6, 44.5±1.6, 44.6±1.4 using on table, handheld while fixing and hand held while non fixing respectively. The average K readings were 44.9±1.4, 44.8±1.3, 45.1±1.3 using on table keratometer, hand held while fixing and dilated, and handheld while non fixing and dilated respectively. the intraclass correlation coefficient was 0.954 when comparing on table and held undilated fixing patient readings. While 0.878 when comparing reading of on table versus handheld non fixing readings in undilated pupils. when comparing readings of ontable keratometry to handheld readings wile fixing and dilated ICC was 0.911. The ICC drops when on table readings were versus hand held readings in non fixing dilated eyes it drops to 0.867

Conclusions:

In our study the Nidek ARK 30 handheld autokeratometer provided reliable readings when used intra operatively on non fixing eyes whether pupils are dilated or undilated. FINANCIAL INTEREST: NONE