Shape of the anterior cornea: comparison of height data from 4 corneal topographers
| Autor: | Nomdo M. Jansonius, Tim de Jong, Matthew Sheehan, M. Dubbelman, Steven A. Koopmans |
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| Přispěvatelé: | Perceptual and Cognitive Neuroscience (PCN), Physics and medical technology, Other Research |
| Rok vydání: | 2012 |
| Předmět: |
Adult
Male ZERNIKE POLYNOMIALS SURFACE ACCURACY Scheimpflug principle OPTICAL ABERRATIONS Coma (optics) Astigmatism Refraction Ocular Standard deviation ASPHERICS Cornea Young Adult Optics medicine Humans Anterior cornea Physics business.industry THEORETICAL EYE Corneal Topography Reproducibility of Results Repeatability HUMAN-EYE Middle Aged medicine.disease Sensory Systems MODEL Ophthalmology Spherical aberration medicine.anatomical_structure Cross-Sectional Studies AGREEMENT Surgery Human eye Female business |
| Zdroj: | Journal of cataract and refractive surgery, 39(10), 1570-1580. ELSEVIER SCIENCE INC de Jong, T, Sheehan, M T, Dubbelman, M, Koopmans, S A & Jansonius, N M 2013, ' Shape of the anterior cornea: Comparison of height data from 4 corneal topographers ', Journal of Cataract & Refractive Surgery, vol. 39, no. 10, pp. 1570-1580 . https://doi.org/10.1016/j.jcrs.2013.04.032 Journal of Cataract & Refractive Surgery, 39(10), 1570-1580. Elsevier Inc. |
| ISSN: | 1873-4502 0886-3350 |
| DOI: | 10.1016/j.jcrs.2013.04.032 |
| Popis: | Purpose To compare the ability of clinical corneal topographers to describe the shape of the anterior cornea for optical modeling. Setting University Medical Center Groningen, Groningen, Netherlands. Design Cross-sectional study. Methods The anterior corneal shape of healthy subjects was assessed with 4 topographers (Atlas Placido disk, Galilei dual Scheimpflug, Orbscan scanning slit, Pentacam single Scheimpflug). Exported height data were fit with Zernike polynomials. Mean values with the standard deviation, interdevice variability, and test–retest variability were determined for the defocus Z(2,0), astigmatism Z(2,−2) and Z(2,2), coma Z(3,−1) and Z(3,1), and spherical aberration Z(4,0) coefficients for 5.5 mm and 8.0 mm diameters. Results At 5.5 mm, the single Scheimpflug topographer showed the smallest coefficient of repeatability; 0.31 μm for Z(2,0); 0.40 and 0.34 μm for Z(2,−2) and Z(2,2), respectively; 0.15 and 0.11 μm for Z(3,−1) and Z(3,1), respectively; and 0.08 μm for Z(4,0); the other topographers showed up to 10 times larger coefficients of repeatability. The (unsigned) mean differences between the topographers were in the range of 0.20 to 1.21 μm for Z(2,0); 0.02 to 0.31 μm and 0.06 to 0.42 μm for Z(2,−2) and Z(2,2), respectively; 0.03 to 0.18 μm and 0.03 to 0.35 μm for Z(3,−1) and Z(3,1), respectively; and 0.00 to 0.14 μm for Z(4,0). The Placido-disk topographer and single Scheimpflug topographer data corresponded best. Similar trends were found at 8.0 mm. Conclusion Test–retest variability hampered a detailed description of the anterior corneal shape at the level of individual subjects; interdevice variability compromises the exchangeability of the devices. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned. |
| Databáze: | OpenAIRE |
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