Non-Contact Intraocular Pressure Measurement Method using Relation between Deformed Cornea and Reflected Pneumatic Pressure

  • Hyung Jin Kim
  • Young Ho Seo
  • Byeong Hee Kim
Regular Paper


Deviating from existing non-contact type of intraocular pressure measurement method, which utilizes pneumatic and optical modules, this paper proposed new measurement method using pneumatic module only. In proposed method, cornea is deformed by pneumatic pressure, and pneumatic pressure reflected on cornea is measured by focus-type hollow nozzle. As a simulation results to verify proposed method, reflected pneumatic pressure decreased as the measured distance increased and the intraocular pressure increased. As an experiment results, the ratio of reflected pneumatic pressure for intraocular pressure of 10, and 50 mmHg at a measurement distance of 3 mm was about 0.21% and 0.16%, and at a measurement distance of 5 mm was about 0.21% and 0.16%, respectively. When intraocular pressure was high, low reflected pneumatic pressure was output, and simulation and experimental results showed same tendency. As a related result with the shape of the deformed cornea, cornea was largely deformed when intraocular pressure was low, and the injected pneumatic pressure was concentrated more within space formed by deformed cornea. The concentrated pneumatic pressure flowed into nozzle, and large amount of reflected pneumatic pressure was collected. The proposed method was investigated through both simulation and experimentally, and possibility was confirmed.


Intraocular pressure Corneal deformation Focus-type hollow nozzle Reflected pneumatic pressure Simulation 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Asrani, S., Zeimer, R., Wilensky, J., Gieser, D., Vitale, S., and Lindenmuth, K., “Large Diurnal Fluctuations in Intraocular Pressure are an Independent Risk Factor in Patients with Glaucoma,” Journal of Glaucoma, vol. 9, no. 2, pp. 134–142, 2000.CrossRefGoogle Scholar
  2. 2.
    Tonnu, P., Ho, T., Sharma, K., White, E., Bunce, C., and Garway-Heath, D., “A Comparison of Four Methods of Tonometry: Method Agreement and Interobserver Variability,” British Journal of Ophthalmology, vol. 89, no. 7, pp. 847–850, 2005.CrossRefGoogle Scholar
  3. 3.
    Gordon, M. O., Beiser, J. A., Brandt, J. D., Heuer, D. K., Higginbotham, E. J., et al., “The Ocular Hypertension Treatment Study: Baseline Factors that Predict the Onset of Primary Open-Angle Glaucoma,” Archives of ophthalmology, vol. 120, no. 6, pp. 714–720, 2002.CrossRefGoogle Scholar
  4. 4.
    Heijl, A., Leske, M. C., Bengtsson, B., Hyman, L., Bengtsson, B., and Hussein, M., “Reduction of Intraocular Pressure and Glaucoma Progression: Results from the Early Manifest Glaucoma Trial,” Archives of Ophthalmology, vol. 120, no. 10, pp. 1268–1279, 2002.CrossRefGoogle Scholar
  5. 5.
    Vernon, S. A., “Non-Contact Tonometry in the Postoperative Eye,” British Journal of Ophthalmology, vol. 73, no. 4, pp. 247–249, 1989.CrossRefGoogle Scholar
  6. 6.
    Burvenich, H., Burvenich, E., and Vincent, C., “Dynamic Contour Tonometry (DCT) Versus Non-Contact Tonometry (NCT): A Comparison Study,” Bulletin De La Sociét Belge D'ophtalmologie, vol. 298, pp. 63–69, 2005.Google Scholar
  7. 7.
    Lee, M. and Ahn, J., “Effects of Central Corneal Stromal Thickness and Epithelial Thickness on Intraocular Pressure Using Goldmann Applanation and Non-Contact Tonometers,” PLoS One, Vol. 11, No. 3, Paper No. e0151868, 2016.Google Scholar
  8. 8.
    Martinez-de-la-Casa, J. M., Garcia-Feijoo, J., Vico, E., Fernandez-Vidal, A., del Castillo, J. M. B., et al., “Effect of Corneal Thickness on Dynamic Contour, Rebound, and Goldmann Tonometry,” Ophthalmology, vol. 113, no. 12, pp. 2156–2162, 2006.CrossRefGoogle Scholar
  9. 9.
    Iliev, M. E., Goldblum, D., Katsoulis, K., Amstutz, C., and Frueh, B., “Comparison of Rebound Tonometry with Goldmann Applanation Tonometry and Correlation with Central Corneal Thickness,” British Journal of Ophthalmology, vol. 90, no. 7, pp. 833–835, 2006.CrossRefGoogle Scholar
  10. 10.
    Pakrou, N., Gray, T., Mills, R., Landers, J., and Craig, J., “Clinical Comparison of the Icare Tonometer and Goldmann Applanation Tonometry,” Journal of Glaucoma, vol. 17, no. 1, pp. 43–47, 2008.CrossRefGoogle Scholar
  11. 11.
    Bonomi, L., Baravelli, S., Cobbe, C., and Tomazzoli, L., “Evaluation of Keeler Pulsair Non-Contact Tonometry: Reliability and Reproducibility,” Graefe's Archive for Clinical and Experimental Ophthalmology, vol. 229, no. 3, pp. 210–212, 1991.CrossRefGoogle Scholar
  12. 12.
    Chakrabarty, L., “Goldmann Applanation Tonometry Versus Non-Contact Tonometry: A Comparative Study,” International Journal of Research in Medical Sciences, vol. 4, no. 11, pp. 4683–4687, 2016.CrossRefGoogle Scholar
  13. 13.
    Farhood, Q. K., “Comparative Evaluation of Intraocular Pressure with an Air-Puff Tonometer Versus a Goldmann Applanation Tonometer,” Clinical Ophthalmology, vol. 7, pp. 23–27, 2013.Google Scholar
  14. 14.
    Do Dnb, M. C. M., “180Years of Evolution in Tonometry,” Kerala Journal of Ophthalmology, vol. 21, no. 2, pp. 173–181, 2009.Google Scholar
  15. 15.
    Luce, D. A., “Determining in Vivo Biomechanical Properties of the Cornea with an Ocular Response Analyzer,” Journal of Cataract & Refractive Surgery, vol. 31, no. 1, pp. 156–162, 2005.CrossRefGoogle Scholar
  16. 16.
    Ogbuehi, K. C., “Assessment of the Accuracy and Reliability of the Topcon Ct80Non-Contact Tonometer,” Clinical and Experimental Optometry, vol. 89, no. 5, pp. 310–314, 2006.CrossRefGoogle Scholar
  17. 17.
    Kim, H. J., “Development of Non-Contact Type Intraocular Pressure Measurement System Based on Rebounding Sound and Air-Pressure,” Ph.D. Thesis, Kangwon National University, Chuncheon, 2016.Google Scholar
  18. 18.
    Sharif, M. A., “Heat Transfer from an Isothermally Heated Flat Surface due to Twin Oblique Slot-Jet Impingement,” Procedia Engineering, vol. 56, pp. 544–550, 2013.CrossRefGoogle Scholar
  19. 19.
    Jenkins, R. C. and Hill Jr, W. G., “Investigation of VTOL Upwash Flows Formed by Two Impinging Jets,” Defense Technical Information Center, Accession No. ADA047805, 1977.Google Scholar
  20. 20.
    Geers, L. F. G., “Multiple Impinging Jet Arrays: An Experimental Study on Flow Hand Heat Transfer,” Ph.D. Thesis, Delft University of Technology, 2004.Google Scholar
  21. 21.
    Fu, T.-L., Deng, X.-T., Liu, G.-H., Wang, Z.-D., and Wang, G.-D., “Experimental Study of Cooling Speed for Ultra-Thick Steel Plate during the Jet Impinging and Quenching Process,” International Journal of Precision Engineering and Manufacturing, vol. 17, no. 11, pp. 1503–1514, 2016.CrossRefGoogle Scholar
  22. 22.
    Kim C. M., Park, S. J., and Kim, G. M., “Development of Multi Sample Array System Based on Pneumatic Valve,” Journal of the Korean Society for Precision Engineering, vol. 34, no. 1, pp. 59–63, 2017.CrossRefGoogle Scholar
  23. 23.
    Fuard, D., Tzvetkova-Chevolleau, T., Decossas, S., Tracqui, P., and Schiavone, P., “Optimization of Poly-Di-Methyl-Siloxane (PDMS) Substrates for Studying Cellular Adhesion and Motility,” Microelectronic Engineering, vol. 85, Nos. 5–6, pp. 1289–1293, 2008.CrossRefGoogle Scholar
  24. 24.
    Pandolfi, A. and Manganiello, F., “A Model for the Human Cornea: Constitutive Formulation and Numerical Analysis,” Biomechanics and Modeling in Mechanobiology, vol. 5, no. 4, pp. 237–246, 2006.CrossRefGoogle Scholar
  25. 25.
    Dupps Jr, W. J. and Wilson, S. E., “Biomechanics and Wound Healing in the Cornea,” Experimental Eye Research, vol. 83, no. 4, pp. 709–720, 2006.CrossRefGoogle Scholar
  26. 26.
    Pandolfi, A. and Holzapfel, G. A., “Three-Dimensional Modeling and Computational Analysis of the Human Cornea Considering Distributed Collagen Fibril Orientations,” Journal of Biomechanical Engineering, Vol. 130, No. 6, Paper No. 061006, 2008.Google Scholar
  27. 27.
    Studer, H., Larrea, X., Riedwyl, H., and Büchler, P., “Biomechanical Model of Human Cornea Based on Stromal Microstructure,” Journal of Biomechanics, vol. 43, no. 5, pp. 836–842, 2010.CrossRefGoogle Scholar
  28. 28.
    Kim, B., Lee, S. B., Lee, J., Cho, S., Park, H., et al., “A Comparison Among Neo-Hookean Model, Mooney-Rivlin Model, and Ogden Model for Chloroprene Rubber,” International Journal of Precision Engineering and Manufacturing, vol. 13, no. 5, pp. 759–764, 2012.CrossRefGoogle Scholar
  29. 29.
    Kling, S. and Marcos, S., “Finite-Element Modeling of Intrastromal Ring Segment Implantation into a Hyperelastic Cornea,” Investigative Ophthalmology & Visual Science, vol. 54, no. 1, pp. 881–889, 2013.CrossRefGoogle Scholar
  30. 30.
    Castro, G. G., Fitt, A. D., and Sweeney, J., “On the Validity of the Imbert-Fick Law: Mathematical Modelling of Eye Pressure Measurement,” World Journal of Mechanics, vol. 6, no. 3, pp. 35–51, 2016.CrossRefGoogle Scholar
  31. 31.
    Sigal, I. A., Flanagan, J. G., and Ethier, C. R., “Factors Influencing Optic Nerve Head Biomechanics,” Investigative Ophthalmology & Visual Science, vol. 46, no. 11, pp. 4189–4199, 2005.CrossRefGoogle Scholar
  32. 32.
    Kling, S., Bekesi, N., Dorronsoro, C., Pascual, D., and Marcos, S., “Corneal Viscoelastic Properties from Finite-Element Analysis of in Vivo Air-Puff Deformation,” PLoS One, Vol. 9, No. 8, Paper No. e104904, 2014.Google Scholar
  33. 33.
    Shimmyo, M., Ross, A. J., Moy, A., and Mostafavi, R., “Intraocular Pressure, Goldmann Applanation Tension, Corneal Thickness, and Corneal Curvature in Caucasians, Asians, Hispanics, and African Americans,” American Journal of Ophthalmology, vol. 136, no. 4, pp. 603–613, 2003.CrossRefGoogle Scholar
  34. 34.
    Elsheikh, A., Alhasso, D., and Rama, P., “Assessment of the Epithelium's Contribution to Corneal Biomechanics,” Experimental Eye Research, vol. 86, no. 2, pp. 445–451, 2008.CrossRefGoogle Scholar
  35. 35.
    Ren, R., Wang, N., Li, B., Li, L., Gao, F., et al., “Lamina Cribrosa and Peripapillary Sclera Histomorphometry in Normal and Advanced Glaucomatous Chinese Eyes with Various Axial Length,” Investigative Ophthalmology & Visual Science, vol. 50, no. 5, pp. 2175–2184, 2009.CrossRefGoogle Scholar
  36. 36.
    Ariza-Gracia, M., Zurita, J. F., Piñero, D. P., Rodriguez-Matas, J. F., and Calvo, B., “Coupled Biomechanical Response of the Cornea Assessed by Non-Contact Tonometry. A Simulation Study,” PLoS One, Vol. 10, No. 3, Paper No. e0121486, 2015.Google Scholar
  37. 37.
    Juraeva, M., Park, B. H., Ryu, K. J., and Song, D. J., “Designing High-Speed Dental Air-Turbine Handpiece by Using a Computational Approach,” International Journal of Precision Engineering and Manufacturing, vol. 18, no. 10, pp. 1403–1407, 2017.CrossRefGoogle Scholar
  38. 38.
    Ko, D.-H., Ko, D.-C., Lim, H.-J., Lee, J.-M., and Kim, B.-M., “FESimulation Coupled with CFD Analysis for Prediction of Residual Stresses Relieved by Cryogenic Heat Treatment of Al6061Tube,” International Journal of Precision Engineering and Manufacturing, vol. 14, no. 8, pp. 1301–1309, 2013.CrossRefGoogle Scholar
  39. 39.
    Kling, S. and Marcos, S., “Contributing Factors to Corneal Deformation in Air Puff Measurements,” Investigative Ophthalmology & Visual Science, vol. 54, no. 7, pp. 5078–5085, 2013.CrossRefGoogle Scholar
  40. 40.
    Ambrósio Jr, R., Ramos, I., Luz, A., Faria, F. C., Steinmueller, A., et al., “Dynamic Ultra High Speed Scheimpflug Imaging for Assessing Corneal Biomechanical Properties,” Revista Brasileira de Oftalmologia, vol. 72, no. 2, pp. 99–102, 2013.CrossRefGoogle Scholar

Copyright information

© Korean Society for Precision Engineering and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Mechanical and Mechatronics EngineeringKangwon National UniversityGangwon-doRepublic of Korea

Personalised recommendations