First Author: S.Chung SOUTH KOREA
Co Author(s): Y. Park
Purpose:
To assess the reproducibility and reliability of the IOL master, A-scan, Pentacam and Orbscan Topography system in measuring anterior chamber depth (ACD)
Setting:
: St. Mary s Hospital, College of Medicine, Seoul, Korea
Methods:
In this prospective study of 200 eyes of 100 patients, ACD estimation prior to cataract surgery was done by 4 methods: IOL master, A-scan, Pentacam, and Orbscan. One observer performed all measurements three times for each test. ACD was defined as the length between the center of anteror surface of cornea and the center of anterior lens surface. Repeatability from each device was evaluated by coefficient of variation, standard deviation and intraclasscorrelation coefficient. RM-ANOVA on Ranks was used to compare the differences in anterior chamber depth among devices. The Bland-Altman plot was performed to assess agreement in measurements between devices.
Results:
The mean ACD by the four methods were 3.25±0.45 mm 2.89±0.49 mm, 3.21±0.46 mm, and 3.19±0.47 mm, respectively: the differences were statistically significant (P<0.01). The coefficient of variation for the four methods were 0.87% in the IOL master, 2.50% in the A-scan, 1.25% in the Scheimpflug camera, 1.04% with Orbscan.
Conclusions:
Applanation A-scan gives lower measurements for ACD compared with IOL master®, Pentacam® and Orbscan II. There was good agreement between results obtained with the latter 3 methods based on optical principles. IOL master®, Pentacam® and Orbscan II will be more clinically useful in evaluating the anterior chamber depth.
Financial Disclosure:
None
