Top

Medical & Biological Engineering & Computing

Published in:

01-08-2006 | Original Article

Underestimation of intraocular pressure after photorefractive keratectomy: a biomechanical analysis

Authors: Per Hallberg, Anders Eklund, Kenneth Santala, Timo Koskela, Olof Lindahl, Christina Lindén

Published in: Medical & Biological Engineering & Computing | Issue 8/2006

Activate our intelligent search to find suitable subject content or patents.

search-config

AI-assisted search

Off

Abstract

Excimer laser surgery, to correct corneal refraction, induces changes in corneal thickness and curvature. Both factors can cause measurement errors when determining intraocular pressure (IOP). This study evaluates effects of photorefractive keratectomy (PRK) on IOP measurements, using Goldmann applanation tonometry (GAT) and Applanation resonance tonometry (ART), in an in vitro model. Six porcine eyes was enucleated and pressurised to a constant IOP = 30 mmHg. After removal of the epithelium, the eyes were PRK-treated for a total of 25 dioptres. The measured IOP decreased 13.2 mmHg for GAT and 9.0 mmHg for ART. The total underestimation by GAT was larger than for ART, and a part of the ART underestimation (3.5 mmHg) was assigned to sensitivity to the change in corneal surface structure resulting from the removal of epithelium. The flat contact probe of GAT, as compared with the convex tip of ART, provided explanation for the difference in IOP measurement error after PRK.

next article Secure and efficient health data management through multiple watermarking on medical images

Dont have a licence yet? Then find out more about our products and how to get one now:

Springer Professional "Wirtschaft+Technik"

Online-Abonnement

Mit Springer Professional "Wirtschaft+Technik" erhalten Sie Zugriff auf:

über 102.000 Bücher
über 537 Zeitschriften

aus folgenden Fachgebieten:

Automobil + Motoren
Bauwesen + Immobilien
Business IT + Informatik
Elektrotechnik + Elektronik
Energie + Nachhaltigkeit
Finance + Banking
Management + Führung
Marketing + Vertrieb
Maschinenbau + Werkstoffe
Versicherung + Risiko

Jetzt Wissensvorsprung sichern!

inform now

Springer Professional "Technik"

Online-Abonnement

Mit Springer Professional "Technik" erhalten Sie Zugriff auf:

über 67.000 Bücher
über 390 Zeitschriften

aus folgenden Fachgebieten:

Automobil + Motoren
Bauwesen + Immobilien
Business IT + Informatik
Elektrotechnik + Elektronik
Energie + Nachhaltigkeit
Maschinenbau + Werkstoffe

Jetzt Wissensvorsprung sichern!

inform now

Springer Professional "Wirtschaft"

Online-Abonnement

Mit Springer Professional "Wirtschaft" erhalten Sie Zugriff auf:

über 67.000 Bücher
über 340 Zeitschriften

aus folgenden Fachgebieten:

Bauwesen + Immobilien
Business IT + Informatik
Finance + Banking
Management + Führung
Marketing + Vertrieb
Versicherung + Risiko

Jetzt Wissensvorsprung sichern!

inform now

Bhan A, Browning AC, Shah S, Hamilton R, Dave D, Dua HS (2002) Effect of corneal thickness on intraocular pressure measurements with the pneumotonometer, Goldmann applanation tonometer, and tono-pen. Invest Ophthalmol Vis Sci 43:1389–1392

Cohan BE, Bohr DF (2001) Goldmann applanation tonometry in the conscious rat. Invest Ophthalmol Vis Sci 42:340–342

Doughty MJ, Zaman ML (2000) Human corneal thickness and its impact on intraocular pressure measures: a review and meta-analysis approach. Surv Ophthalmol 44:367–408CrossRef

Ehlers N, Brahmsen T, Sperling S (1975) Applanation tonometry and central corneal thickness. Acta Ophthalmol 53:34–43

Eisenberg DL, Sherman BG, Mckeown CA, Schuman JS (1998) Tonometry in adults and children. A manometric evaluation of pneumatonometry, applanation, and TonoPen in vitro and in vivo. Ophthalmology 105:1173–1181CrossRef

Eklund A (2002) Resonator sensor technique for medical use—an intraocular pressure measurement system. Umeå University, Umeå

Eklund A, Backlund T, Lindahl OA (2000) A resonator sensor for measurement of intraocular pressure—evaluation in an in vitro pig-eye model. Physiol Meas 21:355–367CrossRef

Eklund A, Bergh A, Lindahl OA (1999) A catheter tactile sensor for measuring hardness of soft tissue: measurement in a silicone model and in an in vitro human prostate model. Med Biol Eng Comput 37:618–624CrossRef

Eklund A, Hallberg P, Lindén C, Lindahl OA (2003) Applanation resonance sensor for measuring intraocular pressure—a continuos force and area measurement method. Invest Ophthalmol Vis Sci 44:3017–3024CrossRef

10.

Eklund A, Lindén C, Backlund T, Andersson B, Lindahl OA (2003) Evaluation of applanation resonator sensors for intraocular pressure measurement, results from clinical and in vitro studies. Med Biol Eng Comput 41:190–197CrossRef

11.

Feltgen N, Leifert D, Funk J (2001) Correlation between central corneal thickness, applanation tonometry, and direct intracameral IOP readings. Br J Ophthalmol 85:85–87CrossRef

12.

Garzozi H, Chung H, Lang Y, Kagemann L, Harris A (2001) Intraocular pressure and photorefractive keratectomy: a comparison of three different tonometers. Cornea 20:33–36CrossRef

13.

Goldmann H (1957) Applanation tonometry. In: Newell FW (eds) Glaucoma, transactions of the second conference. Josiah Macy Jr. Foundation, New York, pp 167–220

14.

Green K (1990) Techniques of intraocular pressure determination. Lens Eye Toxic Res 7:485–489

15.

Hallberg P, Lindén C, Lindahl OA, Bäcklund T, Eklund A (2004) Applanation resonance tonometry for intraocular pressure in humans. Physiol Meas 25:1053–1065CrossRef

16.

Hallberg P, Lindén C, Lindahl OA, Bäcklund T, Eklund A (2006) Comparison of Goldmann applanation- and applanation resonance tonometry in a vertical in vitro porcine-eye model. J Med Eng Technol (in press)

17.

Kaufmann C, Bachmann LM, Thiel MA (2003) Intraocular pressure measurements using dynamic contour tonometry after laser in situ keratomileusis. Invest Ophthalmol Vis Sci 44:3790–3794CrossRef

18.

Liu J, Roberts CJ (2005) Influence of corneal biomechanical properties on intraocular pressure measurement: quantitative analysis. J Cataract Refract Surg 31:146–155CrossRef

19.

Mark H (1973) Corneal curvature in applanation tonometry. Am J Ophthalmol 76:223–224

20.

Moses RA (1958) The Goldmann applanation tonometer. Am J Ophthalmol 46:865–869

21.

Munger R, Dohadwala AA, Hodge WG, Jackson WB, Mintsioulis G, Damji KF (2001) Changes in measured intraocular pressure after hyperopic photorefractive keratectomy. J Cataract Refract Surg 27:1254–1262CrossRef

22.

Olsen T (1986) On the calculation of power from curvature of the cornea. Br J Ophthalmol 70:152–154CrossRef

23.

Omata S, Terunuma Y (1992) New tactile sensor like the human hand and its applications. Sens Actuators 35:9–15CrossRef

24.

Orssengo GJ, Pye DC (1999) Determination of the true intraocular pressure and modulus of elasticity of the human cornea in vivo. Bull Math Biol 61:551–572CrossRef

25.

Rosa N, Cennamo G, Breve MA, La Rana A (1998) Goldmann applanation tonometry after myopic photorefractive keratectomy. Acta Ophthalmol Scand 76:550–554CrossRef

26.

Schmidt T (1957) Zur applanationtonometri an der spaltlampe. Ophthalmologica 133:337–342CrossRef

27.

Siganos DS, Papastergiou GI, Moedas C (2004) Assessment of the Pascal dynamic contour tonometer in monitoring intraocular pressure in unoperated eyes and eyes after LASIK. J Cataract Refract Surg 30:746–751CrossRef

28.

Whitacre MM, Stein R (1993) Sources of error with use of Goldmann-type tonometers. Surv Ophthalmol 38:1–30CrossRef

29.

Whitacre MM, Stein RA, Hassanein K (1993) The effect of corneal thickness on applanation tonometry. Am J Ophthalmol 115:592–596

Title: Underestimation of intraocular pressure after photorefractive keratectomy: a biomechanical analysis
Authors: Per Hallberg
Anders Eklund
Kenneth Santala
Timo Koskela
Olof Lindahl
Christina Lindén
Publication date: 01-08-2006
Publisher: Springer-Verlag
Published in: Medical & Biological Engineering & Computing / Issue 8/2006
Print ISSN: 0140-0118
Electronic ISSN: 1741-0444
DOI: https://doi.org/10.1007/s11517-006-0093-6

Springer Professional

Abstract

Please log in to get access to your license.

Dont have a licence yet? Then find out more about our products and how to get one now:

Springer Professional "Wirtschaft+Technik"

Springer Professional "Technik"

Springer Professional "Wirtschaft"

Other articles of this Issue 8/2006

Finite element contact analysis of the hip joint

The Snellen human calorimeter revisited, re-engineered and upgraded: design and performance characteristics

Towards assessing the sympathovagal balance

A new application of Gompertz function in photohemolysis: the effect of temperature on red blood cell hemolysis photosensitized by protoporphyrin IX

Filtering techniques for the removal of ventilator artefact in oesophageal pulse oximetry

Electronic root canal length measurement before and after experimentally induced pulpitis and apical periodontitis in dogs

Premium Partner