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Graefe's Archive for Clinical and Experimental Ophthalmology

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01-12-2005 | Clinical Investigation

Changes in corneal thickness and curvature after different excimer laser photorefractive procedures and their impact on intraocular pressure measurements

Authors: Helena Svedberg, Enping Chen, Helene Hamberg-Nyström

Published in: Graefe's Archive for Clinical and Experimental Ophthalmology | Issue 12/2005

Abstract

Background

Excimer laser refractive surgery alters the shape and thickness of the cornea by removing central corneal tissue with submicrometer precision. The aim of the study was to analyze the changes in central corneal thickness (CCT) and curvature before and after different excimer laser photorefractive procedures and their possible impact on intraocular pressure (IOP) estimations with Goldmann applanation tonometry.

Methods

Data on CCT, corneal curvature and IOP readings with Goldmann applanation tonometry before and after excimer laser photorefractive surgery were analyzed retrospectively. The data was further analyzed separately in two subgroups; the photorefractive keratectomy /laser-assisted subepithelial keratomileusis (PRK/LASEK) group and the laser in situ keratomileusis (LASIK) group.

Results

The overall post-operative IOP readings were significantly lower than pre-operative values. There was a significant difference in the lowering of the IOP readings between the two subgroups: LASIK caused a lower IOP reading than PRK/LASEK.

Conclusion

The change in corneal thickness and curvature affects the estimation of IOP with Goldmann applanation tonometry after excimer laser photorefractive surgery. The amount of reduction in IOP reading might be influenced by the specific laser surgical procedure. This is of clinical importance in the evaluation of any future glaucoma in the increasing number of patients who undergo photorefractive laser surgery.

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Title: Changes in corneal thickness and curvature after different excimer laser photorefractive procedures and their impact on intraocular pressure measurements
Authors: Helena Svedberg
Enping Chen
Helene Hamberg-Nyström
Publication date: 01-12-2005
Publisher: Springer-Verlag
Published in: Graefe's Archive for Clinical and Experimental Ophthalmology / Issue 12/2005
Print ISSN: 0721-832X
Electronic ISSN: 1435-702X
DOI: https://doi.org/10.1007/s00417-005-0072-x

At a glance: The STEP trials

Springer Medicine

Changes in corneal thickness and curvature after different excimer laser photorefractive procedures and their impact on intraocular pressure measurements

Abstract

Background

Methods

Results

Conclusion

At a glance: The STEP trials

Springer Medicine

Abstract

Background

Methods

Results

Conclusion

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