Abstract
Background: To evaluate the effects of posterior corneal astigmatism and the absolute flat meridian difference between anterior and posterior corneal surfaces (AMDAnt-Post) on the estimation of total corneal astigmatism using anterior corneal measurements (simulated keratometry [K]).
Methods: Ninety-nine eyes of 99 healthy participants were enrolled. Anterior, posterior, and total mean corneal power, cylinder power, flat meridian, and vector components J0, and J45 measured by a dual Scheimpflug camera were analyzed. The correlation between the posterior corneal cylinder power, AMDAnt-Post, and the difference in the cylinder power between simulated K and total cornea (cylinder power differenceSimK-Tot) were evaluated.
Results: The cylinder power differenceSimK-Tot was positively correlated with the posterior corneal cylinder power (rho = 0.704 and P < 0.001) and negatively correlated with AMDAnt-Post (rho = −0.717 and P < 0.001). In the multivariate linear regression analysis, anterior corneal J0 was strongly associated with the posterior corneal cylinder power and the AMDAnt-Post. When corneal J0 had a positive value, the cylinder power of simulated K tended to be larger than the total corneal cylinder power. In comparison, the opposite trend was presented in eyes with negative anterior corneal J0. When anterior corneal J0 was larger than 1.0 or smaller than −0.9, the errors from estimating the total corneal cylinder power using anterior corneal measurements tended to be larger than 0.25 D.
Conclusion: Posterior corneal astigmatism should be considered for more accurate corneal astigmatism predictions, especially in eyes with anterior corneal astigmatism greater than 2.0 D of with-the-rule astigmatism or greater than 1.8 D of against-the-rule astigmatism.
| Original language | English |
|---|---|
| Pages (from-to) | 1769-1777 |
| Number of pages | 9 |
| Journal | Graefe's Archive for Clinical and Experimental Ophthalmology |
| Volume | 252 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - 2014 Jan 1 |
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Keywords
- Anterior corneal astigmatism
- Posterior corneal astigmatism
- Total corneal astigmatism
ASJC Scopus subject areas
- Ophthalmology
- Sensory Systems
- Cellular and Molecular Neuroscience
Cite this
The effect of posterior corneal flat meridian and astigmatism amount on the total corneal astigmatism estimated from anterior corneal measurements. / Eom, Youngsub; Kang, Su Yeon; Kim, Hyo Myung; Song, Jong-Suk.
In: Graefe's Archive for Clinical and Experimental Ophthalmology, Vol. 252, No. 11, 01.01.2014, p. 1769-1777.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - The effect of posterior corneal flat meridian and astigmatism amount on the total corneal astigmatism estimated from anterior corneal measurements
AU - Eom, Youngsub
AU - Kang, Su Yeon
AU - Kim, Hyo Myung
AU - Song, Jong-Suk
PY - 2014/1/1
Y1 - 2014/1/1
N2 - Background: To evaluate the effects of posterior corneal astigmatism and the absolute flat meridian difference between anterior and posterior corneal surfaces (AMDAnt-Post) on the estimation of total corneal astigmatism using anterior corneal measurements (simulated keratometry [K]).Methods: Ninety-nine eyes of 99 healthy participants were enrolled. Anterior, posterior, and total mean corneal power, cylinder power, flat meridian, and vector components J0, and J45 measured by a dual Scheimpflug camera were analyzed. The correlation between the posterior corneal cylinder power, AMDAnt-Post, and the difference in the cylinder power between simulated K and total cornea (cylinder power differenceSimK-Tot) were evaluated.Results: The cylinder power differenceSimK-Tot was positively correlated with the posterior corneal cylinder power (rho = 0.704 and P < 0.001) and negatively correlated with AMDAnt-Post (rho = −0.717 and P < 0.001). In the multivariate linear regression analysis, anterior corneal J0 was strongly associated with the posterior corneal cylinder power and the AMDAnt-Post. When corneal J0 had a positive value, the cylinder power of simulated K tended to be larger than the total corneal cylinder power. In comparison, the opposite trend was presented in eyes with negative anterior corneal J0. When anterior corneal J0 was larger than 1.0 or smaller than −0.9, the errors from estimating the total corneal cylinder power using anterior corneal measurements tended to be larger than 0.25 D.Conclusion: Posterior corneal astigmatism should be considered for more accurate corneal astigmatism predictions, especially in eyes with anterior corneal astigmatism greater than 2.0 D of with-the-rule astigmatism or greater than 1.8 D of against-the-rule astigmatism.
AB - Background: To evaluate the effects of posterior corneal astigmatism and the absolute flat meridian difference between anterior and posterior corneal surfaces (AMDAnt-Post) on the estimation of total corneal astigmatism using anterior corneal measurements (simulated keratometry [K]).Methods: Ninety-nine eyes of 99 healthy participants were enrolled. Anterior, posterior, and total mean corneal power, cylinder power, flat meridian, and vector components J0, and J45 measured by a dual Scheimpflug camera were analyzed. The correlation between the posterior corneal cylinder power, AMDAnt-Post, and the difference in the cylinder power between simulated K and total cornea (cylinder power differenceSimK-Tot) were evaluated.Results: The cylinder power differenceSimK-Tot was positively correlated with the posterior corneal cylinder power (rho = 0.704 and P < 0.001) and negatively correlated with AMDAnt-Post (rho = −0.717 and P < 0.001). In the multivariate linear regression analysis, anterior corneal J0 was strongly associated with the posterior corneal cylinder power and the AMDAnt-Post. When corneal J0 had a positive value, the cylinder power of simulated K tended to be larger than the total corneal cylinder power. In comparison, the opposite trend was presented in eyes with negative anterior corneal J0. When anterior corneal J0 was larger than 1.0 or smaller than −0.9, the errors from estimating the total corneal cylinder power using anterior corneal measurements tended to be larger than 0.25 D.Conclusion: Posterior corneal astigmatism should be considered for more accurate corneal astigmatism predictions, especially in eyes with anterior corneal astigmatism greater than 2.0 D of with-the-rule astigmatism or greater than 1.8 D of against-the-rule astigmatism.
KW - Anterior corneal astigmatism
KW - Posterior corneal astigmatism
KW - Total corneal astigmatism
UR - http://www.scopus.com/inward/record.url?scp=84928771268&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84928771268&partnerID=8YFLogxK
U2 - 10.1007/s00417-014-2737-9
DO - 10.1007/s00417-014-2737-9
M3 - Article
C2 - 25038911
AN - SCOPUS:84928771268
VL - 252
SP - 1769
EP - 1777
JO - Albrecht von Graefes Archiv für Klinische und Experimentelle Ophthalmologie
JF - Albrecht von Graefes Archiv für Klinische und Experimentelle Ophthalmologie
SN - 0065-6100
IS - 11
ER -