Comparison of Conventional Keratometry and Total Keratometry in Normal Eyes

Table 2

Summary of previous studies on comparing simulated keratometry or conventional keratometry, and total keratometry.

Author	Year		Device		Differences between simulated keratometry and total keratometry (D)
			Simulated keratometry (conventional keratometry)	Total keratometry
Wang et al. [1]	2011	94	Galilei (Ziemer, Switzerland)		GEP: 1.30 D
Savini et al. [2]	2013	41	Keraton (Optikon, Spain)	Pentacam HR (OCULUS, Germany)	TNP: 1.30 D
Savini et al. [3]	2017	114	Sirius (CSO Florence, Italy)		TCP:  D^§
Hasegawa et al. [4]	2018	501	CASIA (Tomey, Japan)		RP:  D
Olsen and Jeppesen [5]	2018	20	ARK700^† (conventional keratometry) (Nidek, Japan)	Pentacam HR (OCULUS, Germany)	Ray-traced corneal power:  D
Current study		50	TONOREF II^† (conventional keratometry) (Nidek, Japan)	Pentacam HR (OCULUS, Germany); CASIA 2 (Tomey, Japan)	TCRP:  D; TNP:  D; RP:  D

Simulated keratometry was measured with the corneal topography/tomography. ^†Conventional keratometry was measured with the automated keratometer. GEP = Gaussian equivalent power calculated by the Gaussian formula. ^§TCP = total corneal power calculated by ray tracing.