Goldmann applanation tonometry versus non-contact tonometry: a comparative study

Authors

  • Lipi Chakrabarty Department of Ophthalmology, Chandulal Chandrakar Memorial Medical College & Hospital, Durg, Chhattisgarh, India

DOI:

https://doi.org/10.18203/2320-6012.ijrms20163547

Keywords:

Central corneal thickness, Goldmann applanation tonometry, Intraocular pressure, Non-contact tonometry, Tonometer

Abstract

Background: Intraocular pressure (IOP) measurement is a routine procedure in complete ophthalmologic examination and finds importance in diagnosis and monitoring of glaucoma. Goldmann applanation tonometry and non-contact tonometry, though age old, are still widely used methods of measuring IOP, especially in developing countries like India. This study was undertaken to compare IOP measured with Goldmann applanation tonometer (GAT) and non-contact tonometer (NCT) and to determine the correlation between intraocular pressure and central corneal thickness (CCT).

Methods: This was a cross sectional and observational study wherein adult patients visiting a medical hospital were included. IOP measurements of one hundred and forty four eyes (glaucomatous and non-glaucomatous) were performed using GAT and NCT. The IOP values were compared in different IOP ranges using Bland Altman graph. CCT was measured and its correlation with GAT and NCT analyzed using linear regression analysis.

Results: Both methods of tonometry correlated significantly with each other. The mean of paired difference between GAT and NCT was 1.24±1.38 mmHg (r=0.95, p<0.001). A positive correlation between CCT and both GAT and NCT was found with a regression of 0.35 mmHg per 10 micrometer change in corneal thickness.

Conclusions: Pressure readings of GAT and NCT are comparable. Ophthalmologists need to keep in mind the variation of IOP with CCT. Suitable correction table needs to be devised when considering different CCT ranges for both methods of tonometry.

References

Gupta V, Sony P, Agarwal HC, Sihota R, Sharma A. Inter-instrument agreement and influence of central corneal thickness on measurements with Goldmann, pneumotonometer and noncontact tonometer in glaucomatous eyes. Indian J Ophthalmol. 2006;54:261-5.

Allingham RR, Damji K, Freedman S, Moroi SE, Rhee DJ, Shields MB. Intraocular pressure and Tonometry. In: Shields Textbook Of Glaucoma.6th ed. New Delhi: Wolters Kluwer/Lippincott Williams & Wilkins. 2011;24-40.

Ko WC, Liu CL, HsuWM. Varying effects of corneal thickness on intraocular pressure measurements with different tonometers. Eye 2005;19:327-32.

Bhan A, Browning AC, Shah S, Hamilton R, Dave D, Dua HS. Effect of corneal thickness on intraocular pressure measurements with the pneumotonometer, Goldmann Applanation tonometer and tonopen. Invest Ophthalmol Vis Sci 2002;43:1389-92.

Masumoto T, Makino H, Uazoto H, Saishin M, Miyamoto. The influence of corneal thickness and curvature on the difference between intraocular pressure measurements obtained with a noncontact tonometer and those with a Goldmann Applanation tonometer. Jpn J Ophthalmol. 2000;44:691.

Jorge J, Diaz-Rey JA, Gonzalez-Meijome JM, Almeida JB, Parafita MA. Clinical performance of the Reichert AT 550: A new noncontact tonometer. Ophthalmic Physiol Opt. 2002;22:560-4.

Parker VA, Herrtage J, Sarkies NJ. Clinical comparison of KeelerPulsair 3000 with Goldmann applanation tonometry. Br J Ophthalmol. 2001;85:1301-4.

Moseley MJ, Evans NM, Fielder AR. Comparison of a New Non-Contact Tonometer with Goldmann Applanation. Eye. 1989;3:332-7.

Tonnu PA, Ho T, Newson T, El Sheikh A, Sharma K, White E, et al . The influence of central corneal thickness and age on intraocular pressure measures by pneumotonometry, non-contact tonometry, the Tono PenXL and Goldmann applanation tonometry. Br J Ophthalmol. 2005;89:851-4.

Gunvant P, Baskaran M, Vijaya L, Joseph IS, Watkins RJ, Nallapothula M, et al. Effect of corneal parameters on measurements using the pulsatile ocular blood flow tonograph and Goldmann applanation tonometer. Br J Ophthalmol. 2004;88:518-22.

Foster PJ, Basaanhu J, Alsbirk PH, Munkhbayar D, Uranchimeg D, Johnson GJ. Central corneal thickness and intraocular pressure in a Mongolian population. Ophthalmology. 1998;105:969-73.

Kniestedt C, Lin S, Choe J, Bostrom A, Nee M, Stamper RL, et al. Clinical Comparison of Contour and Applanation Tonometry and Their Relationship to Pachymetry. Arch Ophthalmol. 2005;123:1532-7.

Pelit A, Altan-Yaycioglu R, Pelit A, Akova YA. Effect of corneal thickness on intraocular pressure measurements with the Pascal dynamic contour, Canon Tx-10 noncontact and Goldmann applanation tonometers in healthy subjects. Clin Exp Optom. 2009;92:14-8.

Ehlers N, Bramsen T, Sperling S. Applanation tonometry and central corneal thickness. Acta Ophthalmol. 1975;53:34-43.

Downloads

Published

2016-12-19

How to Cite

Chakrabarty, L. (2016). Goldmann applanation tonometry versus non-contact tonometry: a comparative study. International Journal of Research in Medical Sciences, 4(11), 4683–4687. https://doi.org/10.18203/2320-6012.ijrms20163547

Issue

Section

Original Research Articles