J Korean Ophthalmol Soc.  2009 May;50(5):664-669. 10.3341/jkos.2009.50.5.664.

Comparison of Corneal Thickness and Anterior Chamber Depth Measured With Orbscan, Pentacam, and Ultrasound Pachymetry

• Park JY
• Kim SY
• Jung MS

• KMID: 2212295
• DOI: http://doi.org/10.3341/jkos.2009.50.5.664

Abstract

PURPOSE:We compared the measurements of corneal thickness and anterior chamber depth (ACD) using three different methods Orbscan, Pentacam and ultrasound pachymetry.
METHODS
In healthy volunteers, central corneal thickness was measured with Orbscan, Pentacam and ultrasound pachymetry. Estimation of peripheral corneal thickness and ACD were done by Orbscan and Pentacam. All results were compared statistically.
RESULTS
The mean central corneal thickness of 64 eyes measured by Orbscan, Pentacam and ultrasound pachymetry were 509.1+/-61.0 microm, 539.2+/-51.7 microm and 527.4+/-48.3 microm, respectively. There were statistically significant differences in the results among the three methods (repeated-measures analysis of variance (ANOVA), p<0.05). There were significant correlations between the ultrasonic pachymetry, the Orbscan and the Pentacam (Pearson correlation, r>0.90, p<0.05). The temporal and nasal peripheral corneal thicknesses were thinner in the Pentacam than in the Orbscan (paired t-test, p<0.05). The superior and inferior corneal thickness and ACD were not significantly different.
CONCLUSIONS
The results of the three instruments have significant correlations with each other, so all methods are clinically useful.

Keyword

Anterior chamber depth; Corneal thickness; Orbscan; Pentacam; Ultrasound pachymetry

MeSH Terms

Anterior Chamber
Eye
Ultrasonics

Figure

• 

  Figure 1. The correlation plot of the central corneal thickness (CCT) measured by Ultrasound pachymetry (US), Orbscan (ORB) and Pentacam (in μm). (A) US CCT and ORB CCT (r=0.968, p=0.000), (B) US CCT and Pentacam CCT (r=0.927, p=0.000), (C) Pentacam CCT and ORB CCT (r=0.965, p=0.000).

• 

  Figure 2. The correlation plot of the anterior chamber depth (ACD, in mm) measured by Orbscan (Orb) and Pentacam (r=0.67, p<0.05)

Reference

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