Original articleAccuracy of Total Corneal Astigmatism Measurements With a Scheimpflug Imager and a Color Light-Emitting Diode Corneal Topographer
Section snippets
Subjects
This prospective validity assessment was conducted at the Rotterdam Ophthalmic Institute, Rotterdam, Netherlands. Ninety-one eyes of 91 patients who underwent cataract surgery with implantation of a monofocal, non-toric IOL were enrolled. If both eyes of a patient were eligible for inclusion, the eye that was operated most recently was selected. Exclusion criteria were corneal diseases (eg, keratoconus, corneal scarring, pterygium), pseudoexfoliation syndrome, previous corneal or refractive
Results
Mean patient age was 69.4 ± 8.4 years (range 45.9–90.0). Forty-one patients (45%) were men, and 50 eyes (55%) were right eyes. The mean preoperative axial length was 23.92 ± 1.39 mm (range, 20.89–27.63), and the mean preoperative corneal power was 43.64 ± 1.48 D (range, 40.30–47.44). Measurements of acceptable quality could be obtained for the Pentacam and Cassini in 78 (86%) and 60 eyes (66%), respectively. An overview of the astigmatism magnitudes as measured with the different devices is
Discussion
The main outcome variable in this study was the accuracy of corneal astigmatism measurements, expressed as the vectorial difference between the corneal measurements and the refractive astigmatism. With mean values of 0.61 and 0.58 D for the Pentacam and Cassini, respectively, the accuracy for measurements of the anterior corneal surface of these devices was similar (independent-samples t test, P = .59). When measurements of the total instead of only anterior corneal astigmatism were performed,
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2019, Journal of Cataract and Refractive SurgeryCorneal dioptric power and astigmatism: A comparison between colour light-emitting diode based (Cassini<sup>TM</sup>) and Scheimpgflug technology (Pentacam<sup>TM</sup>) topography
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2019, American Journal of OphthalmologyToric outcomes: Computer-assisted registration versus intraoperative aberrometry
2017, Journal of Cataract and Refractive SurgeryCitation Excerpt :Therefore, reproducible corneal analysis was crucial for inclusion. The study by Klijn et al.,28 which compared a Scheimpflug imager with a color diode corneal topographer, found the reduced levels of residual cylinder could be achieved when considering the back surface of the cornea as part of the total corneal astigmatism rather than considering the anterior corneal astigmatism alone. However, we used the traditional model of a surgically induced corneal astigmatism of 0.0 temporally to allow for a clinical application to be derived from traditional autokeratometry.
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