J Korean Ophthalmol Soc.  2014 Jul;55(7):984-990.

Comparative Analysis of Corneal Refractive Power Measured with AL-Scan(R), Autokeratometer, and Pentacam(R)

• Park SJ
• Lim SH
• Lee HY

Abstract

PURPOSE
To investigate clinical availability of AL-Scan(TM) (Nidek, Gamagori, Japan) by comparing corneal refractive power with AL-Scan(TM), Autokeratometer(TM) (Topcon KR-1, Tokyo, Japan) and Pentacam(TM) (Oculus, Wetzlar, Germany) devices.
METHODS
Seventy-one patients (142 eyes) who visited our hospital for refractive surgery were tested using AL-Scan(R), Autokeratometer and Pentacam(R) and corneal refractive power was compared among devices.
RESULTS
When comparing measurements with AL-Scan(R), Autokeratometer and Pentacam(R), the mean corneal refractive power was 43.37 +/- 1.32 D (2.4 mm zone), 43.35 +/- 1.32 D (3.3 mm zone), 43.36 +/- 1.35 D, and 43.35 +/- 1.36 D respectively and showed no significant differences. Corneal refractive power had strongly positive linear correlation (p < 0.001) and Bland-Altman plots showed high degree of agreement among AL-Scan(R), Autokeratometer and Pentacam(R) devices.
CONCLUSIONS
Because measuring ocular biometry with AL-Scan(R) including axial length, intraocular lens power calculation and topography simultaneously is possible, clinical use is convenient. Corneal refractive power was not different when compared with autokeratometer and Pentacam(R) devices, thus, AL-Scan(R) can be used in the clinical environment.

Keyword

AL-Scan(R); Autokeratometer; Corneal refractive power; Pentacam(R)

MeSH Terms

Biometry
Humans
Lenses, Intraocular
Refractive Surgical Procedures

Figure

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  Figure 1. Pearson correlation of corneal refractive power (K) measured with AL-Scan®, Autokeratometer and Pentacam®.

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  Figure 2. Bland-Altman plots of corneal refractive power (K) measured with AL-Scan®, Autokeratometer and Pentacam®.

Reference

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