Youngje Sung1, Sokjoong Chung1, Sang Min Nam2. 1. Department of Ophthalmology, CHA Bundang Medical Center, CHA University, 59 Yatap-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-712, Republic of Korea. 2. Department of Ophthalmology, CHA Bundang Medical Center, CHA University, 59 Yatap-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-712, Republic of Korea. Electronic address: forustous@cha.ac.kr.
Abstract
PURPOSE: A new method to measure the horizontal corneal diameter using a Scheimpflug image (SFI) was introduced and compared with the automated iris camera photo (ICP) method on the Pentacam. METHODS: Each one eye of 88 subjects without significant abnormality in the cornea was included. In SFI, diameters were measured manually using the built-in software tool with the edge-filter option. ICP value read from the overview display. Repeatability was determined from the first two measurements of each eye. The accuracy was assessed using Bland-Altman plot in comparison with caliper measurements. RESULTS: The measurement failure rate of ICP was aggravated by pupil dilation, while that of SFI was unrelated to pupil dilation. Repeatability coefficients of ICP and SFI were 0.1mm and 0.12mm, respectively. The mean difference between ICP values and caliper values was not significant. SFI values were greater than caliper measurements by a mean of 0.13mm. CONCLUSIONS: New SFI was reliable and could complement ICP in dilated pupil. The measurement failure rates of Pentacam need to be improved.
RCT Entities:
PURPOSE: A new method to measure the horizontal corneal diameter using a Scheimpflug image (SFI) was introduced and compared with the automated iris camera photo (ICP) method on the Pentacam. METHODS: Each one eye of 88 subjects without significant abnormality in the cornea was included. In SFI, diameters were measured manually using the built-in software tool with the edge-filter option. ICP value read from the overview display. Repeatability was determined from the first two measurements of each eye. The accuracy was assessed using Bland-Altman plot in comparison with caliper measurements. RESULTS: The measurement failure rate of ICP was aggravated by pupil dilation, while that of SFI was unrelated to pupil dilation. Repeatability coefficients of ICP and SFI were 0.1mm and 0.12mm, respectively. The mean difference between ICP values and caliper values was not significant. SFI values were greater than caliper measurements by a mean of 0.13mm. CONCLUSIONS: New SFI was reliable and could complement ICP in dilated pupil. The measurement failure rates of Pentacam need to be improved.