Comparison of Anterior, Posterior, and Total Corneal Astigmatism Measured Using a Single Scheimpflug Camera in Healthy and Keratoconus EyesComparison of Anterior, Posterior, and Total Corneal Astigmatism Measured Using a Single Scheimpflug Camera in Healthy and Keratoconus Eyes
- Other Titles
- Comparison of Anterior, Posterior, and Total Corneal Astigmatism Measured Using a Single Scheimpflug Camera in Healthy and Keratoconus Eyes
- Authors
- 최영; 엄영섭; 송종석; 김효명
- Issue Date
- 2018
- Publisher
- 대한안과학회
- Keywords
- Astigmatism; Cornea; Keratoconus; Posterior corneal astigmatism; Total corneal astigmatism
- Citation
- Korean Journal of Ophthalmology, v.32, no.3, pp.163 - 171
- Indexed
- KCI
- Journal Title
- Korean Journal of Ophthalmology
- Volume
- 32
- Number
- 3
- Start Page
- 163
- End Page
- 171
- URI
- https://scholar.korea.ac.kr/handle/2021.sw.korea/80255
- DOI
- 10.3341/kjo.2017.0075
- ISSN
- 1011-8942
- Abstract
- Purpose: To compare the effect of posterior corneal astigmatism on the estimation of total corneal astigmatism using anterior corneal measurements (simulated keratometry [K]) between eyes with keratoconus and healthy eyes. Methods: Thirty-three eyes of 33 patients with keratoconus of grade I or II and 33 eyes of 33 age- and sexmatched healthy control subjects were enrolled. Anterior, posterior, and total corneal cylinder powers and flat meridians measured by a single Scheimpflug camera were analyzed. The difference in corneal astigmatism between the simulated K and total cornea was evaluated. Results: The mean anterior, posterior, and total corneal cylinder powers of the keratoconus group (4.37 ± 1.73, 0.95 ± 0.39, and 4.36 ± 1.74 cylinder diopters [CD], respectively) were significantly greater than those of the control group (1.10 ± 0.68, 0.39 ± 0.18, and 0.97 ± 0.63 CD, respectively). The cylinder power difference between the simulated K and total cornea was positively correlated with the posterior corneal cylinder power and negatively correlated with the absolute flat meridian difference between the simulated K and total cornea in both groups. The mean magnitude of the vector difference between the astigmatism of the simulated K and total cornea of the keratoconus group (0.67 ± 0.67 CD) was significantly larger than that of the control group (0.28 ± 0.12 CD). Conclusions: Eyes with keratoconus had greater estimation errors of total corneal astigmatism based on anterior corneal measurement than did healthy eyes. Posterior corneal surface measurement should be more emphasized to determine the total corneal astigmatism in eyes with keratoconus.
- Files in This Item
- There are no files associated with this item.
- Appears in
Collections - College of Medicine > Department of Medical Science > 1. Journal Articles
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.