Comparison of corneal parameters in keratoconic subjects obtained from the pentacam and visante omni

Deepa Viswanathan, Nikhil L. Kumar, John J. Males, Stuart Graham

Research output: Contribution to journalMeeting abstract

Abstract

Purpose: To compare corneal measurements including elevation, curvature and thickness values obtained using two imaging systems, a Scheimpflug camera (Pentacam) and an optical coherence tomography device (Visante OMNI) in keratoconic subjects. Methods: Corneal measurements from 35 eyes (22 subjects) were obtained using both devices and compared. Agreement was determined using the Bland- Altman analysis 95% limits of agreement (LoA). Results: The Pentacam measured significantly greater simulated keratometry readings in the flattest meridian (K1) (45.29 ± 3.48 diopters (D) versus 44.92 ± 2.97 D, p = 0.04) and in the steepest meridian (K2) (48.29 ± 3.83D versus 47.88 ± 3.49 D, p = 0.01). The Bland Altman 95% LoA between the devices were from −1.59 to 2.33 D for K1 and from −1.35 to 2.17 D for K2. Pentacam anterior corneal elevations were significantly higher (p = 0.03) as were posterior corneal elevations (p < 0.0001). The 95% LoA were from −15.59 to 24.51 μ and from −22.92 to 48.78 μ for anterior and posterior corneal elevations respectively. Compared to Visante OMNI, Pentacam recorded greater central corneal thickness (CCT) and minimum corneal pachymetry (MCP) values by 19.41 ± 18.25 μ and 13.03 ± 12.22 μ respectively (both p < 0.0001). The 95% LoA were from −16.37 to 55.19 μ for CCT and from −10.92 to 36.98 μ for MCP values. Conclusions: The Pentacam measured significantly greater corneal curvature, elevation and thickness values compared to Visante OMNI. In clinical practice, these devices are not interchangeable for corneal measurements in keratoconic subjects.
Original languageEnglish
Article number1307
Pages (from-to)35
Number of pages1
JournalClinical and Experimental Ophthalmology
Volume41
Issue numberSuppl. 1
DOIs
Publication statusPublished - Nov 2013
EventAnnual Scientific Congress of Royal Australian and New Zealand College of Ophthalmologists (45th : 2013) - Hobart
Duration: 2 Nov 20136 Nov 2013

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