Abstract
Anterior and posterior corneal astigmatism must both be considered when calculating toric intraocular lenses (IOLs). The purpose of the two studies discussed in this chapter was to assess the relationship between anterior and posterior corneal astigmatisms and to evaluate the clinical impact of posterior corneal astigmatism on surgical outcomes following implantation of toric IOLs. Anterior and posterior corneal astigmatisms (CAant and CApost, respectively) were measured using the Galilei combined Placido dual Scheimpflug analyzer, and the correlation between them and age was investigated. In addition, pre- and postoperative corneal astigmatism prediction errors were calculated for the IOLMaster, Lenstar, Atlas, manual keratometer, and Galilei. The mean magnitude of CAant was 1.20 ± 0.79 D (diopters) (standard deviation) and of CApost was −0.30 ± 0.15 D. With increasing age, the anterior corneal steeper meridian shifted from vertical to horizontal, while the posterior corneal steeper meridian maintained a vertically aligned steeper meridian. The IOLMaster, Lenstar, Atlas, and manual keratometry had a mean corneal astigmatism prediction error of 0.5–0.6 D of with-the-rule (WTR) astigmatism in eyes with WTR corneal astigmatism and of 0.2–0.3 D of WTR astigmatism in eyes with against-the-rule (ATR) corneal astigmatism. These errors are attributable to posterior corneal astigmatism. In conclusion, ignoring the posterior corneal astigmatism when planning astigmatic correction during cataract surgery may lead to overcorrection in eyes with WTR anterior corneal astigmatism and undercorrection in eyes with ATR anterior corneal astigmatism.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Hoffmann PC, Hutz WW. Analysis of biometry and prevalence data for corneal astigmatism in 23,239 eyes. J Cataract Refract Surg. 2010;36(9):1479–85. doi:10.1016/j.jcrs.2010.02.025.
Ferrer-Blasco T, Montes-Mico R, Peixoto-de-Matos SC, Gonzalez-Meijome JM, Cervino A. Prevalence of corneal astigmatism before cataract surgery. J Cataract Refract Surg. 2009;35(1):70–5. doi:10.1016/j.jcrs.2008.09.027.
Visser N, Bauer NJ, Nuijts RM. Toric intraocular lenses: historical overview, patient selection, IOL calculation, surgical techniques, clinical outcomes, and complications. J Cataract Refract Surg. 2013;39(4):624–37. doi:10.1016/j.jcrs.2013.02.020.
Sun XY, Vicary D, Montgomery P, Griffiths M. Toric intraocular lenses for correcting astigmatism in 130 eyes. Ophthalmology. 2000;107(9):1776–81. discussion 1781–1772.
Mendicute J, Irigoyen C, Aramberri J, Ondarra A, Montes-Mico R. Foldable toric intraocular lens for astigmatism correction in cataract patients. J Cataract Refract Surg. 2008;34(4):601–7. doi:10.1016/j.jcrs.2007.11.033.
Teus MA, Arruabarrena C, Hernandez-Verdejo JL, Sales-Sanz A, Sales-Sanz M. Correlation between keratometric and refractive astigmatism in pseudophakic eyes. J Cataract Refract Surg. 2010;36(10):1671–5. doi:10.1016/j.jcrs.2010.05.010.
Ho JD, Tsai CY, Liou SW. Accuracy of corneal astigmatism estimation by neglecting the posterior corneal surface measurement. Am J Ophthalmol. 2009;147(5):788–95. doi:10.1016/j.ajo.2008.12.020. 795. e781–782.
Dubbelman M, Sicam VA, Van der Heijde GL. The shape of the anterior and posterior surface of the aging human cornea. Vision Res. 2006;46(6–7):993–1001. doi:10.1016/j.visres.2005.09.021.
Prisant O, Hoang-Xuan T, Proano C, Hernandez E, Awwad ST, Azar DT. Vector summation of anterior and posterior corneal topographical astigmatism. J Cataract Refract Surg. 2002;28(9):1636–43.
Modis Jr L, Langenbucher A, Seitz B. Evaluation of normal corneas using the scanning-slit topography/pachymetry system. Cornea. 2004;23(7):689–94.
Koch DD, Ali SF, Weikert MP, Shirayama M, Jenkins R, Wang L. Contribution of posterior corneal astigmatism to total corneal astigmatism. J Cataract Refract Surg. 2012;38(12):2080–7. doi:10.1016/j.jcrs.2012.08.036.
Koch DD, Jenkins R, Weikert MP, Yeu E, Wang L. Correcting astigmatism with toric intraocular lenses: the effect of posterior corneal astigmatism. J Cataract Refract Surg. 2013;39:1803.
Holladay JT, Moran JR, Kezirian GM. Analysis of aggregate surgically induced refractive change, prediction error, and intraocular astigmatism. J Cataract Refract Surg. 2001;27(1):61–79.
Royston JM, Dunne MC, Barnes DA. Measurement of posterior corneal surface toricity. Optom Vis Sci. 1990;67(10):757–63.
Dunne MC, Royston JM, Barnes DA. Posterior corneal surface toricity and total corneal astigmatism. Optom Vis Sci. 1991;68(9):708–10.
Ho JD, Tsai CY, Tsai RJ, Kuo LL, Tsai IL, Liou SW. Validity of the keratometric index: evaluation by the Pentacam rotating Scheimpflug camera. J Cataract Refract Surg. 2008;34(1):137–45. doi:10.1016/j.jcrs.2007.09.033.
Grosvenor T, Quintero S, Perrigin DM. Predicting refractive astigmatism: a suggested simplification of Javal’s rule. Am J Optom Physiol Opt. 1988;65:292–7.
Alpins NA. New method of targeting vectors to treat astigmatism. J Cataract Refract Surg. 1997;23(1):65–75.
Bae JG, Kim SJ, Choi YI. Pseudophakic residual astigmatism. Korean J Ophthalmol. 2004;18(2):116–20.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2014 Springer Japan
About this chapter
Cite this chapter
Ventura, B.V., Wang, L., Weikert, M.P., Koch, D.D. (2014). Correction of Corneal Astigmatism with Toric IOLs. In: Bissen-Miyajima, H., Koch, D., Weikert, M. (eds) Cataract Surgery: Maximizing Outcomes Through Research. Springer, Tokyo. https://doi.org/10.1007/978-4-431-54538-5_8
Download citation
DOI: https://doi.org/10.1007/978-4-431-54538-5_8
Published:
Publisher Name: Springer, Tokyo
Print ISBN: 978-4-431-54537-8
Online ISBN: 978-4-431-54538-5
eBook Packages: MedicineMedicine (R0)