J Korean Ophthalmol Soc.  2014 Dec;55(12):1758-1764. 10.3341/jkos.2014.55.12.1758.

Comparison of Keratometry and Corneal Higher Order Aberrations between Scout Videokeratoscope and Pentacam Scheimpflug Camera

• Shin JY
• Lee MY
• Chung SH

• KMID: 2338957
• DOI: http://doi.org/10.3341/jkos.2014.55.12.1758

Abstract

PURPOSE
To investigate the correlations of keratometry and corneal high order aberrations (HOAs) between the Keratron Scout videokeratoscope and the Pentacam HR Scheimpflug camera.
METHODS
From December 2012 to February 2013, keratometry and corneal HOAs were determined using the Keratron Scout videokeratoscope and Pentacam HR Scheimpflug camera in 23 healthy individuals (46 eyes).
RESULTS
Average keratometry showed high correlation with 95% confidence interval -0.155 +/- 0.37 between the Keratron Scout and Pentacam HR. When comparing HOAs of the Keratron Scout and total corneal HOAs of Pentacam HR, total root-mean-square (RMS), and spherical aberration were positively correlated between the 2 devices (r = 0.67, p < 0.001 and r = 0.74, p < 0.001, respectively). When comparing HOAs of Keratron Scout and anterior corneal HOAs of Pentacam HR, total RMS, spherical aberration and coma were positively correlated between the 2 devices (r = 0.62, p < 0.001, r = 0.81, p < 0.001, and r = 0.52, p = 0.047, respectively).
CONCLUSIONS
Although the 2 devices are based upon different principles, the Keratron Scout videokeratoscope and Pentacam HR Scheimpflug camera showed positive correlations in keratometry, total RMS, spherical aberration, and coma. Both devices may be useful for clinical applications.

Keyword

Higher order aberrations; Keratometry; Keratron Scout videokeratoscope; Pentacam HR Scheimpflug camera; Spherical aberration

MeSH Terms

Coma

Figure

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  Figure 1. The comparison of average keratometry (K) between the Keratron Scout videokeratoscopy and Pentacam HR Scheimpflug Camera. The solid line represents ±0.37 standard deviation confidence interval (CI) (i.e. 95% of the points should fall within these lines).

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  Figure 2. The correlation between corneal higher order aberrations (HOAs) of the Keratron Scout videokeratoscopy and total corneal HOAs of Pentacam HR Scheimpflug Camera. RMS = root-mean-square; SA = spherical aberration.

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  Figure 3. The correlation between corneal higher order aberrations (HOAs) of Keratron Scout videokeratoscopy and anterior corneal HOAs of Pentacam HR Scheimpflug Camera. RMS = root-mean-square; SA = spherical aberration.

Reference

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