Comparison of central corneal thickness measurements using Pentacam and ultrasonic pachymetry in post-LASIK eyes for myopia

Journal Article

HS, Al-Mezaine . 2010

• Publication Online URL: Comparison of central corneal thickness measurements using Pentacam and ultrasonic pachymetry in post-LASIK eyes for myopia
• Magazine \ Newspaper: European Journal of Ophthalmology
• Issue Number: 5
• Volume Number: 20
• Pages: 852 to 857

Publication Abstract

Purpose. To compare central corneal thickness (CCT) measurements obtained using the Pentacam
Scheimpflug system with those obtained using DGH ultrasound pachymetry (UP) in post–laser in situ
keratomileusis (LASIK) eyes for myopia.
Methods. In a prospective study, measurement agreement was assessed in 143 eyes of 72 post-LASIK
patients using both the Pentacam and UP at the Eye Consultants Center in Riyadh, Saudi Arabia.
Results. The mean CCT was 522±42.2 μm with the Oculus Pentacam and 516.2±40.6 μm with UP.
The Bland-Altman plot showed that the mean ± SD for the differences between the 2 devices was
5.8±13.6 μm, with 95% confidence interval limits ranging from −20.9 μm to 32.6 μm. A test of statistical
significance indicated that the mean differences of 5.8±13.6 μm differed significantly from zero
(p<0.001; Wilcoxon signed-rank test), thus indicating that the Pentacam measurements tended to
overestimate CCT compared with UP. Analysis of regression showed a high correlation between the
values obtained with both devices (r=0.947, p<0.001).
Conclusions. In post-LASIK myopic eyes, although a high correlation has been shown between Pentacam
and UP measurements, Pentacam tends to overestimate CCT compared to UP. Pentacam
probably cannot be used interchangeably with UP in post-LASIK eyes for myopia. (Eur J Ophthalmol
2010; 20: 852-7)
Key Words. Corneal thickness