J Korean Ophthalmol Soc.  2012 Oct;53(10):1412-1418.

Corneal Thickness Measured by Dual Scheimpflug, Anterior Segment Optical Coherence Tomography, and Ultrasound Pachymetry

• Kim DW
• Yi KY
• Choi DG
• Shin YJ

Abstract

PURPOSE
To compare central corneal thickness (CCT) as measured by dual rotating Scheimpflug camera (Galilei), anterior segment optical coherence tomography (AS-OCT), and ultrasound pachymetry (USP).
METHODS
The measurements of CCT using a dual rotating Scheimpflug camera, AS-OCT, and USP in 40 eyes of 20 healthy subjects were compared.
RESULTS
The average measurements of CCT by dual rotating Scheimpflug camera, AS-OCT, and USP were 538.10 +/- 31.36 microm, 536.20 +/- 31.21 microm, and 541.93 +/- 34.93 microm, respectively. The CCT measurement by USP was statistically significantly thicker than by the dual rotating Scheimpflug camera and AS-OCT (p = 0.017, p = 0.001, respectively). There was no significant difference between the dual rotating Scheimpflug camera and AS-OCT (p = 0.054). A significant linear correlation was observed between the dual rotating Scheimpflug camera, the AS-OCT, and the USP (r > 0.900, p < 0.001).
CONCLUSIONS
The results of the 3 methods have significant correlation with each other, but the measurement by USP was significantly thicker than the dual rotating Scheimpflug camera and AS-OCT. Therefore, CCT should be interpreted in the context of the instrument used.

Keyword

Anterior segment optical coherence tomography; Central corneal thickness; Dual rotating scheimpflug camera; Galilei; Ultrasound pachymetry

MeSH Terms

Eye
Tomography, Optical Coherence

Figure

• 

  Figure 1 Scattergram showing the correlation of central corneal thickness measured by Galilei, anterior segment optical coherence tomography (AS-OCT), and ultrasound pachtmetry (USP). (A) Correlation between Galilei and USP. (B) Correlation between Galilei and AS-OCT. (C) Correlation between AS-OCT and USP.

• 

  Figure 2 Bland Altman plots between the 2 methods. The middle line is the mean and the lines on the side represent the upper and lower 95% limits of agreement (LoA). (A) Galilei and ultrasound pachymetry (USP). (B) Galilei and anterior segment optical coherence tomography (AS-OCT). (C) AS-OCT and USP.

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