TY - JOUR
T1 - Comparison of keratometry measurements using the Pentacam HR, the Orbscan IIz, and the TMS-4 topographer
AU - Tajbakhsh, Zahra
AU - Salouti, Ramin
AU - Nowroozzadeh, Mohammad H.
AU - Aghazadeh-Amiri, Mohammad
AU - Tabatabaee, Seyedmehdi
AU - Zamani, Mohammad
PY - 2012/11
Y1 - 2012/11
N2 - Purpose: To compare and evaluate the agreement between keratometry readings using three devices: the Pentacam HR, the Orbscan IIz, and the TMS-4 topographer. Methods: In this prospective comparative study, 115 eyes from 115 healthy refractive surgery candidates were sequentially examined using three devices. Fourier analysis was used to evaluate corneal astigmatism in these subjects. The outcome measures comprised steep and flat keratometry readings, corneal astigmatism, the mean keratometry reading, and the J0 and J45 components. Repeated-measures analysis of variance (RM-anova) and Bland-Altman plots with 95% limits of agreement were used to evaluate the difference between measurements. Results: The mean keratometry readings were 43.89 ± 1.51, 43.52 ± 1.48, and 43.79 ± 1.50 D using the TMS-4 topographer, the Orbscan IIz, and the Pentacam HR, respectively (p < 0.001; RM-anova). The mean keratometric astigmatism was 1.27 ± 0.87, 1.20 ± 0.86, and 1.21 ± 0.82 D using the TMS-4 topographer, the Orbscan IIz, and the Pentacam HR, respectively (p = 0.007; RM-anova). The J0 measurements were higher using the TMS-4 topographer compared with the Orbscan IIz (p = 0.021; Bonferroni test). The mean, steep, and flat keratometry data were in better agreement using the TMS-4 topographer and the Pentacam HR. In general, the Orbscan IIz device measured lower values than either the TMS-4 topographer or the Pentacam HR. However, the corneal astigmatism measurements and the J0 component showed the best agreement using the TMS-4 topographer and the Orbscan IIz. Conclusions: The TMS-4 topographer and the Pentacam HR produced similar readings and can be used interchangeably to measure simulated keratometry values in young, healthy eyes. To measure corneal astigmatism, the TMS-4 topographer and the Orbscan IIz produced values that were similar and could be used interchangeably.
AB - Purpose: To compare and evaluate the agreement between keratometry readings using three devices: the Pentacam HR, the Orbscan IIz, and the TMS-4 topographer. Methods: In this prospective comparative study, 115 eyes from 115 healthy refractive surgery candidates were sequentially examined using three devices. Fourier analysis was used to evaluate corneal astigmatism in these subjects. The outcome measures comprised steep and flat keratometry readings, corneal astigmatism, the mean keratometry reading, and the J0 and J45 components. Repeated-measures analysis of variance (RM-anova) and Bland-Altman plots with 95% limits of agreement were used to evaluate the difference between measurements. Results: The mean keratometry readings were 43.89 ± 1.51, 43.52 ± 1.48, and 43.79 ± 1.50 D using the TMS-4 topographer, the Orbscan IIz, and the Pentacam HR, respectively (p < 0.001; RM-anova). The mean keratometric astigmatism was 1.27 ± 0.87, 1.20 ± 0.86, and 1.21 ± 0.82 D using the TMS-4 topographer, the Orbscan IIz, and the Pentacam HR, respectively (p = 0.007; RM-anova). The J0 measurements were higher using the TMS-4 topographer compared with the Orbscan IIz (p = 0.021; Bonferroni test). The mean, steep, and flat keratometry data were in better agreement using the TMS-4 topographer and the Pentacam HR. In general, the Orbscan IIz device measured lower values than either the TMS-4 topographer or the Pentacam HR. However, the corneal astigmatism measurements and the J0 component showed the best agreement using the TMS-4 topographer and the Orbscan IIz. Conclusions: The TMS-4 topographer and the Pentacam HR produced similar readings and can be used interchangeably to measure simulated keratometry values in young, healthy eyes. To measure corneal astigmatism, the TMS-4 topographer and the Orbscan IIz produced values that were similar and could be used interchangeably.
KW - Corneal topography
KW - Keratometry
KW - Orbscan IIz
KW - Pentacam HR
KW - TMS-4 topographer
UR - http://www.scopus.com/inward/record.url?scp=84867410213&partnerID=8YFLogxK
U2 - 10.1111/j.1475-1313.2012.00942.x
DO - 10.1111/j.1475-1313.2012.00942.x
M3 - Article
C2 - 23057566
AN - SCOPUS:84867410213
SN - 0275-5408
VL - 32
SP - 539
EP - 546
JO - Ophthalmic and Physiological Optics
JF - Ophthalmic and Physiological Optics
IS - 6
ER -