Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/14080
Title: Correction on the distortion of Scheimpflug imaging for dynamic central corneal thickness
Authors: Li, T
Tian, L
Wang, L
Hon, Y
Lam, AKC 
Huang, Y
Wang, Y
Zheng, Y
Keywords: Central corneal thickness
Corvis ST
Dynamic analysis
Ray tracing
Scheimpflug imaging
Issue Date: 2015
Publisher: SPIE
Source: Journal of biomedical optics, 2015, v. 20, no. 5, 056006 How to cite?
Journal: Journal of Biomedical Optics 
Abstract: The measurement of central corneal thickness (CCT) is important in ophthalmology. Most studies concerned the value at normal status, while rare ones focused on its dynamic changing. The commercial Corvis ST is the only commercial device currently available to visualize the two-dimensional image of dynamic corneal profiles during an air puff indentation. However, the directly observed CCT involves the Scheimpflug distortion, thus misleading the clinical diagnosis. This study aimed to correct the distortion for better measuring the dynamic CCTs. The optical path was first derived to consider the influence of factors on the use of Covis ST. A correction method was then proposed to estimate the CCT at any time during air puff indentation. Simulation results demonstrated the feasibility of the intuitive-feasible calibration for measuring the stationary CCT and indicated the necessity of correction when air puffed. Experiments on three contact lenses and four human corneas verified the prediction that the CCT would be underestimated when the improper calibration was conducted for air and overestimated when it was conducted on contact lenses made of polymethylmethacrylate. Using the proposed method, the CCT was finally observed to increase by 66 34 ?m at highest concavity in 48 normal human corneas.
URI: http://hdl.handle.net/10397/14080
ISSN: 1083-3668
DOI: 10.1117/1.JBO.20.5.056006
Appears in Collections:Journal/Magazine Article

Access
View full-text via PolyU eLinks SFX Query
Show full item record

SCOPUSTM   
Citations

6
Last Week
0
Last month
0
Citations as of Aug 13, 2017

WEB OF SCIENCETM
Citations

6
Last Week
0
Last month
0
Citations as of Aug 14, 2017

Page view(s)

28
Last Week
2
Last month
Checked on Aug 13, 2017

Google ScholarTM

Check

Altmetric



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.