J Korean Ophthalmol Soc.  2014 Jun;55(6):801-808.

Measurement Comparison of Anterior Segment Parameters between AL-Scan(R) and Pentacam(R)

• Youn SM
• Lim SH
• Lee HY

Abstract

PURPOSE
To investigate the clinical availability of AL-Scan(R) (Nidek, GAMAGORI, Japan) by comparing anterior segment parameters measured with AL-Scan(R) and Pentacam(R) (Oculus, Wetzlar, Germany).
METHODS
Seventy-three patients (117 eyes) who received refractive surgery at our hospital were tested with AL-Scan(R) and Pentacam(R). We compared measurements including anterior chamber depth, central corneal thickness, white-to-white, and corneal curvature.
RESULTS
When comparing measurements obtained with AL-Scan(R) and Pentacam(R), the anterior chamber depth (p < 0.001), central corneal thickness (p < 0.001) and 2.4 mm zone K value (p = 0.038) showed significant differences; the white-to-white (p = 0.348) and 3.3 mm zone K value (p = 0.429) showed no significant differences. All AL-Scan(R) and Pentacam(R) parameters had a strong positive linear correlation (p < 0.001). The Bland-Altman plots showed a high degree of agreement between AL-Scan(R) and Pentacam(R) in all parameters except for anterior chamber depth.
CONCLUSIONS
AL-Scan(R) is convenient to use clinically because simultaneous measurements of ocular biometry including axial length, intraocular lens power, and topography are possible. However, because differences in some anterior segment parameters exist when compared with Pentacam(R), measurements with AL-Scan(R) may require comparisons with other instruments.

Keyword

AL-Scan(R); Anterior chamber depth; Central corneal thickness; Corneal refractive power; Pentacam(R)

MeSH Terms

Anterior Chamber
Biometry
Humans
Lenses, Intraocular
Refractive Surgical Procedures

Figure

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  Figure 1. Pearson correlation of AL-Scan® and Pentcam® in anterior segment parameters. ACD = anterior chamber depth; CCT = central corneal thickness; WTW = white-to-white; K = keratometric diopter.

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  Figure 2. Bland-Altman plots of AL-Scan® and Pentacam® in anterior segment parameters. ACD = anterior chamber depth; CCT = central corneal thickness; WTW= white-to-white; K = keratometric diopter.

Reference

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