Reproducibility of Corneal Graft Thickness measurements with COLGATE in patients who have undergone DSAEK (Descemet Stripping Automated Endothelial Keratoplasty)

BMC Medical Imaging

Jodhbir S Mehta²  Donald T Tan⁴  Jiang Liu¹  Jun Cheng¹  Beng H Lee¹  Hla M Htoon⁵  Annabel Chew³  Melissa HY Wong³ 

[1] Institute for Infocomm Research (I2R), Infocomm, Singapore;Department of Clinical Sciences, Duke-NUS Graduate Medical School, Duke-NUS, Singapore;Singapore National Eye Centre (SNEC), 11 Third Hospital Avenue, 168751, SNEC, Singapore;Yong Loo Lin School of Medicine, National University of Singapore, Yong Loo Lin, Singapore;Singapore Eye Research Institute (SERI), SERI, Singapore

关键词: Graft thickness;    Descemet Stripping Automated Endothelial Keratoplasty;    Anterior segment optical coherence tomography;   

Others  :  1091819
DOI  :  10.1186/1471-2342-12-25

 received in 2011-11-16, accepted in 2012-07-17,  发布年份 2012

【 摘 要 】

Background

The CorneaL GrAft Thickness Evaluation (COLGATE) system was recently developed to facilitate the evaluation of corneal graft thickness from OCT images. Graft thickness measurement can be a surrogate indicator for detecting graft failure or success. The purpose of this study was to determine the reproducibility of the COLGATE system in measuring DSAEK graft area between two observers.

Methods

This was a prospective case series in which 50 anterior segment OCT images of patients who had undergone DSAEK in either eye were analysed. Two observers (MW, AC) independently obtained the image analysis for the graft area using both semi automated and automated method. One week later, each observer repeated the analysis for the same set of images. Bland-Altman analysis was performed to analyze inter and intra observer agreement.

Results

There was strong intraobserver correlation between the 2 semi automated readings obtained by both observers. (r = 0.936 and r = 0.962). Intraobserver ICC for observer 1 was 0.936 (95% CI 0.890 to 0.963) and 0.967 (95% CI 0.942 to 0.981) for observer 2. Likewise, there was also strong interobserver correlation (r = 0.913 and r = 0.969). The interobserver ICC for the first measurements was 0.911 (95% CI 0.849 to 0.949) and 0.968 (95% CI 0.945 to 0.982) for the second. There was statistical difference between the automatic and the semi automated readings for both observers (p = 0.006, p = 0.003). The automatic readings gave consistently higher values than the semi automated readings especially in thin grafts.

Conclusion

The analysis from the COLGATE programme can be reproducible between different observers. Care must be taken when interpreting the automated analysis as they tend to over estimate measurements.

【 授权许可】

   
2012 Wong et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

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