J Korean Ophthalmol Soc.  2016 Jul;57(7):1056-1062. 10.3341/jkos.2016.57.7.1056.

Comparison of Anterior Segment Measurements between Dual and Single Scheimpflug Camera

• An Y
• Kim H
• Joo CK

• KMID: 2317565
• DOI: http://doi.org/10.3341/jkos.2016.57.7.1056

Abstract

PURPOSE
To assess the degree of agreement of two rotating Scheimpflug cameras, Galilei G6 and Pentacam HR, in measuring corneal refractive power (K), anterior chamber depth (ACD), and central corneal thickness (CCT).
METHODS
Measurement agreement was assessed in 40 eyes of 40 outpatients at our hospital. Measurements of anterior and posterior corneal refractive power (K), ACD, and CCT were compared between the Galilei G6 and Pentacam HR.
RESULTS
For Galilei G6 (4 mm), Pentacam HR (3 mm) and Pentacam HR (4 mm), the anterior corneal refractive powers (K) were 44.35 ± 1.38 D, 44.09 ± 1.32 D, and 44.12 ± 1.35 D, respectively, and the posterior corneal refractive powers (K) were 6.39 ± 0.23 D, 6.45 ± 0.23 D, 6.45 ± 0.22 D. The differences in the results were statistically significant. The average ACD measurements using Galilei G6 and Pentacam HR were 3.26 ± 0.42 mm and 3.17 ± 0.42 mm, respectively, and the average CCT measurements were 556.65 ± 30.12 µm and 553.78 ± 29.42 µm. The differences in the measurements were statistically significant. In addition, ACD 95% limits of agreement (LoA) between Galilei G6 and Pentacam HR were in the range of -0.14~0.32 mm, and CCT 95% LoA were in the range of -12.54~18.29 µm.
CONCLUSIONS
There were significant differences in measurements of anterior and posterior corneal refractive power (K), ACD, and CCT between the two cameras. Agreement analysis suggests that Galilei G6 and Pentacam HR should not be used interchangeably.

Keyword

Anterior chamber depth; Central corneal thickness; Corneal refractive power; Scheimpflug camera

MeSH Terms

Anterior Chamber
Humans
Loa
Outpatients

Figure

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  Figure 1. Pearson correlation of Galilei G6 and Pentacam HR in anterior segment parameters. (A) Anterior mean keratometric diopter (K mean) (Pentacam HR 3 mm), (B) Posterior K mean (Pentacam HR 3 mm), (C) Anterior K mean (Pentacam HR 4 mm), (D) Posterior K mean (Pentacam HR 4 mm), (E) anterior chamber depth (ACD), (F) central corneal thickness (CCT). K = keratometric diopter.

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  Figure 2. Bland-Altman plots of Galilei G6 and Pentacam HR in anterior segment parameters. (A) Anterior mean keratometric diopter (K mean) (Pentacam HR 3 mm), (B) Posterior K mean (Pentacam HR 3 mm), (C) Anterior K mean (Pentacam HR 4 mm), (D) Posterior K mean (Pentacam HR 4 mm), (E) anterior chamber depth (ACD), (F) central corneal thickness (CCT). K = keratometric diopter.

Reference

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