Table 5 Published literature on WTW corneal diameter of healthy eyes comparing different devices
From: Comparison of white-to-white measurements using four devices and their determination of ICL sizing
Author | Year | Devices/study group | Subjects | Results |
|---|---|---|---|---|
Baumeister et al. [18] | 2004 | Holladay-Godwin gauge, Zeiss IOLMaster, Orbscan | 100 eyes (61 subjects) | The coefficient of inter-rater repeatability (COR) and LOA was 1.30 and − 0.82 to 1.77 mm for the caliper, 0.92 and − 0.82 to 1.01 mm for the Holliday Godwin gauge, 0.76 and − 0.75 to 0.79 mm for the Orbscan II and 0.50 and − 0.48 to 0.50 mm for the IOLMaster |
Martin et al. [20] | 2013 | Group 1 comprised eyes with low myopia (< 6.00 D) Group 2 comprised moderately myopic eyes (6.00 to 12.00 D) Group 3 comprised extremely myopic eyes (> 12.00 D) | 328 eyes (64 subjects) | Eyes with moderate (LOA − 1.04 to 0.02 mm; r = 0.69) and high myopia (LOA − 0.85 to − 0.19 mm; r = 0.94) had lower WTW diameters than eyes with low myopia (LOA − 1.02 to 0.05 mm; r = 0.76) measured with Orbscan and IOLMaster Orbscan topography provided less WTW distance than IOLMaster in myopic eyes, and thus the devices are not clinically interchangeable |
Salouti et al. [24] | 2009 | Galilei, EyeSys, Orbscan II | 74 eyes (37 subjects) | The best 95% LOA between devices were for the Galilei and the Orbscan II (− 0.72, 1.48; r = 0.40) The best 95% LOA between two eyes for each device were found with the Orbscan II (− 0.15, 0.17; r = 0.99) Results suggest that measurements made with the Orbscan II are smaller than those obtained with the EyeSys Corneal Analysis system and the Galilei |
Salouti et al. [19] | 2013 | Pentacam HR, Orbscan II | 101 eyes (101 subjects) | The mean difference between the Pentacam HR versus Orbscan IIz measurements was 0.10 ± 0.12 mm (95% confidence interval, 0.07–0.12, P < 0.001) The measurements were highly correlated (r = 0.948, P < 0.001) and the 95% LOAs for the Pentacam HR versus the Orbscan II were − 0.14 to 0.33 mm The observed differences in WTW distance readings between the Pentacam HR and the Orbscan IIz are clinically irrelevant, and the two devices can be used interchangeably in clinical practice |
Guber et al. [25] | 2015 | Pentacam, Biograph Devices, HiScan Device | 107 eyes (56 subjects) | The Allegro BioGraph measures of WTW were wider than those taken with the Pentacam (bias = 0.26 mm, P < 0.01) The repeatability STS measured with the HiScan was 0.39 mm, which was significantly reduced (0.15 mm) when the average of two measures was used Agreement between the horizontal WTW measures and horizontal STS estimates when bias was accounted for was r = 0.54 with the Pentacam and r = 0.64 with the BioGraph Large inter device bias was observed for WTW and STS measures |
Fernández et al. [26] | 2019 | Orbscan and Keratograph | 192 eyes of 192 subjects | Manual keratograph overestimated the WTW versus manual Orbscan in 0.13 ± 0.18 mm (P < 0.001) but not in the automated method comparison, 0.01 ± 0.19 mm (P = 0.58) Inter-examiner reproducibility was higher with manual Orbscan than with manual keratograph, and the intra-examiner R decreased with the average of two measures in both cases Probability of confounding sizing was higher with the increase of mean differences, the LOAs, and R WTW from 11.1 to 11.2 mm, 11.6 to 11.7 mm, and 12.3 to 12.4 mm resulted in higher PCS |