Comparability and Intra-/Interobserver Reliability of Anterior Chamber Depth Measurements With the Pentacam and IOLMaster

Abstract

<H4>PURPOSE</H4> <p>To assess the comparability and intra-/ interobsever reliability of central anterior chamber depth measurements obtained using the Pentacam and IOLMaster.</p> <H4>METHODS</H4> <p>Anterior chamber depth was measured in 50 eyes (25 healthy volunteers)—three times on each eye by two independent observers with each method. A total of 12 measurements were performed on each eye. Analysis of variance was used to analyze the data. Mean values, standard deviations, and confidence limits (95% confidence interval) of the two modalities, two observers, and every observer/modality interaction were calculated.</p> <H4>RESULTS</H4> <p>The mean anterior chamber depth values were 3.23±0.031 mm for the IOLMaster and 3.21±0.033 mm for the Pentacam. No statistically significant difference was noted in measurements between the two modalities (<i>P</i>=.291) or between the two observers (<i>P</i>=.903). Observer/modality interaction was not significant (<i>P</i>=.643). The confi dence limits for observer 1 were 3.223±0.03 mm and 3.226±0.03 mm for observer 2. The confidence limits were: observer 1/IOLMaster, 3.23±0.04 mm; observer 2/IOLMaster, 3.24±0.04 mm; observer 1/Pentacam, 3.21±0.04 mm; and observer 2/Pentacam, 3.20±0.04 mm. The differences in measurements ranged from -0.14 to +0.10 mm for the IOLMaster and from -0.08 to +0.12 mm for the Pentacam. The worst deviation from the average eye reading of 3.23 mm was only 0.14 (4.3%).</p> <H4>CONCLUSIONS</H4> <p>Good agreement exists between anterior chamber depth measurements by the IOLMaster and Pentacam in the assessment of normal eyes, and they offer observer-independent results. Therefore, the modalities are interchangeable. [<cite>J Refract Surg</cite>. 2008;24:615-618.]</p> <h4>ABOUT THE AUTHORS</h4> <p>From Birmingham and Midland Eye Centre, Birmingham (Savant); and Wolverhampton & Midland Counties Eye Infirmary, Wolverhampton (Chavan, Pushpoth, Ilango), United Kingdom.</p> <p>The authors have no financial or proprietary interest in the materials presented herein.</p> <p>This study was presented as an E-paper at the International Society of Refractive Surgery of the American Academy of Ophthalmology Annual Regional Meeting; May 26-28, 2006; Istanbul, Turkey.</p> <p>Correspondence: Vijay Savant, FRCS(Ed), MRCOphth, Birmingham and Midland Eye Centre, Dudley Road, Birmingham B18 7QH, United Kingdom. Tel: 44 1215 543801; Fax: 44 1902 645018; E-mail: <a href="mailto:vijaysavant@hotmail.com">vijaysavant@hotmail.com</a></p> <p>Received: December 25, 2006</p> <p>Accepted: July 10, 2007</p> <p><b>Posted online: January 15, 2008</b></p>

Interchangeability between Pentacam and IOLMaster in Phakic Intraocular Lens Calculation

“…Our results are not in agreement with Savant et al (22) and Woodmass and Rocha (2), who did not obtain any statistically significant differences between Pentacam and IOLMaster, which may be due to their small sample size and inclusion of normal eyes only in the Savant et al (22) study.…”

Corneal topography with Scheimpflug imaging and videokeratography: Comparative study of normal eyes

“…4,19 In addition, several studies have compared this Scheimpflug system with established clinical instruments for measuring corneal thickness [9][10][11]13,20,21 and anterior chamber parameters. 15,16,18,20,22,23 23 To evaluate the capability of the Pentacam HR system to measure anterior corneal topography, we compared its measurements in a large population of young adult subjects with normal corneas with measurements taken with a Placido disk-based videokeratoscope (Medmont E300, Medmont Pty. Ltd.) that has been found to be highly accurate and repeatable.…”

Effect of cycloplegia on axial length and anterior chamber depth measurements in children

“…The IOLMaster uses partial coherent interferometry in measuring axial length and optical pachymetry in measuring ACD 2–5,9–12 . Both of these techniques may be affected by accommodation and ACD appears to be reduced during accommodation 13 .…”

“…The IOLMaster uses partial coherent interferometry in measuring axial length and optical pachymetry in measuring ACD. [2][3][4][5][9][10][11][12] Both of these techniques may be affected by accommodation and ACD appears to be reduced during accommodation. 13 In axial length measurement, the IOLMaster converts optical path length into geometrical length using an average refractive index.…”