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Category: Volume 07 Issue 05 May 2019
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Title: Correlation between Central Corneal thickness and Intraocular Pressure measured with Goldmann Applanation Tonometer (GAT) in healthy individuals

Author: Dr Shazia Qayum

 DOI: https://dx.doi.org/10.18535/jmscr/v7i5.153

Abstract

Introduction: Intraocular pressure (IOP) measurement is one of the vital and most commonly performed examination in ophthalmology. Goldmann applanation tonometer (GAT) has been labelled as gold standard for measurement of Intraocular pressure. IOP measurement is known to be affected by Central corneal thickness (CCT). It has been stated that thinner corneas leads to false low IOP interpretations while thicker corneas leads to false high IOP interpretations, thus causing apparent normal tension glaucoma (NTG) and ocular hypertension (OHT) respectively.

Objective: To  evaluate the effect of CCT on IOP readings by Goldmann Applanation Tonometry in healthy individuals

Methodology: This prospective study included 200 eyes of 100 patients attending the outpatient department of ophthalmology, from January 2018 to June 2018, in MMIMSR, Mullana. The patients included were devoid of any corneal disorder, history of antiglaucoma medications, keratitis, keratoconus, corneal scar, corneal dystrophy and degeneration. A total number of 200 eyes were investigated using the Ultrasonic topography system and Goldmann Applanation Tonometry. The minimum CCT was 415μm, maximum CCT was 648 μm with mean CCT being 528.5 μm with SD ± 29.48μm. The minimum IOP  recorded was 9 mmHg, maximum IOP was 22 mmHg and mean IOP was 14.92 mmHg with SD ±2.98 mmHg

Conclusion: In our study, we found that Central corneal thickness was correlated with intraocular pressure significantly in both men and women. Athick cornea leads to an overestimation of IOP while thin cornea leads to an underestimation of IOP.

Keywords: Central corneal thickness, Intraocular pressure, Goldmann Applanation Tonometer, pachymetry, Glaucoma.

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Corresponding Author

Dr Shazia Qayum

MS Ophthalmology DNB Ophthalmology

Assistant Professor, GMC Rajouri (Incharge Head)