This Article  • Full text  • PDF  • Reply to article  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citation map  • Citing articles on HighWire  • Citing articles on ISI (21)  • Contact me when this article is cited  Related Content  • Similar articles in this journal  Topic Collections  • Corneal Disorders  • Alert me on articles by topic

Markus Kohlhaas, MD; Andreas G. Boehm, MD; Eberhard Spoerl, PhD; Antje Pürsten, Dipl-Ing (FH); Hans J. Grein, MD; Lutz E. Pillunat, MD

Arch Ophthalmol. 2006;124:471-476.

Objective  To evaluate the effect of central corneal thickness (CCT), corneal curvature, and axial length on applanation tonometry in an in vivo study.

Methods  In a masked, prospective clinical trial, we examined 125 eyes of 125 patients scheduled for cataract surgery. Corneal curvature was measured by means of keratometry and axial length by A-scan ultrasonography. By cannulating the anterior chamber before surgery, intraocular pressure (IOP) was set to 20, 35, and 50 mm Hg in a closed system by means of a water column. After measuring thickness, the IOP was measured with an applanation tonometer. Pearson product moment correlations and multiple linear regression analyses were performed, and significance levels were evaluated by the paired, 2-tailed t test.

Results  The difference between measured and real IOP was significantly dependent (P<.001) on CCT. The associations between IOP and corneal curvature or IOP and axial length were not statistically significant (P = .31). The association between IOP reading and CCT is shown in the "Dresdner correction table," which illustrates an approximately 1-mm Hg correction for every 25-µm deviation from a CCT of 550 µm. The correction values were positive as thickness decreased and negative as thickness increased.

Conclusions  Central corneal thickness significantly affects IOP readings obtained by applanation tonometry according to the Goldmann principle. A correction of IOP readings by considering CCT according to the Dresdner correction table might be helpful for determining an accurate IOP value.

Author Affiliations: Department of Ophthalmology, University Carl Gustav Carus, Dresden (Drs Kohlhaas, Boehm, Spoerl, and Pillunat), and Department of Optometry, University of Applied Sciences, Jena (Ms Pürsten and Dr Grein), Germany. Dr Kohlhass is now with the Augenklinik, St. Johannes-Hospital, Dortmund, Germany.

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

Dynamic Contour Tonometry in Comparison to Intracameral IOP Measurements
Boehm et al.
IOVS 2008;49:2472-2477.
ABSTRACT | FULL TEXT  

Reproducibility and Clinical Relevance of the Ocular Response Analyzer in Nonoperated Eyes: Corneal Biomechanical and Tonometric Implications
Moreno-Montanes et al.
IOVS 2008;49:968-974.
ABSTRACT | FULL TEXT  

The effect of contact lens induced oedema on the accuracy of Goldmann tonometry in a mature population
Hamilton et al.
Br. J. Ophthalmol. 2007;91:1636-1638.
ABSTRACT | FULL TEXT  

Genetic Contributions to Glaucoma: Heritability of Intraocular Pressure, Retinal Nerve Fiber Layer Thickness, and Optic Disc Morphology
van Koolwijk et al.
IOVS 2007;48:3669-3676.
ABSTRACT | FULL TEXT  

What Happens to Intraocular Pressure at High Altitude?
Somner et al.
IOVS 2007;48:1622-1626.
ABSTRACT | FULL TEXT  

Central corneal thickness and correlation to optic disc size: a potential link for susceptibility to glaucoma
Pakravan et al.
Br. J. Ophthalmol. 2007;91:26-28.
ABSTRACT | FULL TEXT