Kibern. vyčisl. teh., 2018, Issue 1 (191), pp.
Kaplin I.V.1, Ophthalmologist of the Kyiv Center of Therapy and Microsurgery of Eye,
Postgraduate student of department of ophthalmology
Kochina M.L.2, Dr (Biology), Professor,
Head of Department of Medical and Biological Bases of Sport
and Physical Rehabilitation
Firsov A.G.3, PhD (Engineering),
Main Designer of LLC “ASTER-IT”
1Kharkov Medical Academy of Postgraduate Education,
Аmosov st, 58, Kharkiv, 61000, Ukraine
2 Petro Mohyla Black Sea National University,
68 Marines st., 10, Mykolay, 54003, Ukraine
3 Limit Liability Company “ASTER-IT”,
Aviation st., 1, ap. 7, Kharkov, 61166, Ukraine
THE CONCEPTION OF TELEMEDICINE SYSTEM FOR EXPRESS ESTIMATION OF INTRAOCULAR PRESSURE’S LEVEL
Introduction. One of the reasons for the unfavorable outcome of glaucoma is an incorrect evaluation of the eye hydrodynamics data obtained by measuring intraocular pressure. That is why the development of new non-invasive methods of intraocular pressure studying is an urgent task. The cornea is optically anisotropic due to the effects of direct extraocular muscles and intraocular pressure on it, as well as the structure and properties of corneal collagen. When an eye cornea is illuminated by polarized light, we can observe an interference pattern which reflects the distribution of internal stresses in it. The parameters of interference patterns depend on the level of intraocular pressure.
The purpose of the article is to develop the telemedicine system’s conception for express estimation of intraocular pressure level with the use of interference pictures that are observed on glaucoma patients’ cornea in polarized light.
Results. The method for determining the interference parameters is performed in several stages in accordance with the developed algorithm. First, after receiving a color picture of interference pattern, its brightness is normalized and converted to monochrome. At the second stage, the cornea borders are fixed by means of two mode indicators, after which the contour is automatically applied to the image. At the third stage, the isochromatic contour is labeled using an adjustable ring pointer, which allows defining the isochrome width middle and standardizing the studies. After marking out the contour of the isochrome using splines, the isochrome itself is modeled. At the fourth stage, there is an automated calculation of the pixels forming the isochrome and filling the inner part.
Conclusions. To assess the level of intraocular pressure using interference patterns, it is necessary to determine their parameters, which can be performed in a semi-automated mode. The developed method provides a resolving power of at least 0.55 mm/pixel (3 times better than the known one) and reduces the research time by 11–15 times. It is not labor-intensive and can be implemented in the central regional hospital.
Keywords: telemedical system, polarized light, interference patterns, isochromes, parametrization.
- Rykov S.A., Vitovskaya O.P., Stepaniuk G.I. Morbidity, prevalence of ophthalmopathology and disability due to it in Ukraine. News of Glaucoma. 2009. № 1. P.34–35 (in Russian).
- Vodovozov A.M., Kovylin V.V. Use of the polarization-optical method for diagnosing the state of oculomotor muscles with vertical deviation. Ophthalmological Journal. 1990. № 4. P. 201–204 (in Russian).
- Method of intraocular pressure measurement: pat. 33640, Ukraine: IPC A 61 V 3/16, A 61 V 8/10. №u 2007 11716; claimed 23.10.2008; published 10.07.2008 Bull. № 13. 4 p.
- Kochina M.L., Kalimanov V.G. Methods of image processing for automation of pathology diagnosis of extraocular muscles. Applied Radioelectronics. 2008. Vol. 7, № 1. P. 93–96 (in Russian).
- Kochina M.L., Kaplin I.V., Kovtun N.M. Results of polarized light using in the eye studying. Bulletinon the Problems of Biology and Medicine-2014. Iss. 4, vol. 1 (113). P. 139–145 (in Russian).
- Penkov M.A., Kochina M.L. Interference method in the diagnosis of strabismus. Ophthalmological Journal. 1979. № 8. P. 497–498 (in Russian).
- Penkov M.A., Kochina M.L Interference method in the diagnosis of strabismus. Bulletin of Ophthalmology. 1981. № 1. P. 39–41 (in Russian).
- Penkov M.A., Kochina M.L. Application of polarized light in ophthalmology (review). Ophthalmological Journal. 1981. № 6. P. 368–372 (in Russian).
- Penkov M.A., Tamarova R.M., Kochina M.L. Polarization method of studying the eye cornea. News of Medical Technology: a collection of articles. Moscow, 1982. Iss. 1. P. 27–30 (in Russian).
- Zandman F. The photoelastic effect of the living eye. Experim. Mechanics. 1966. Vol. 6, № 5. P. 19–25.
- Bour L.J. Lopez Cardozo N.J. On the birefringence of the living human eye. Vision Res. 1981. Vol. 21, № 9. P. 1413–1421.
- Komai Y., Ushiki T. The three dimensional organization of collagen fibrils in the human cornea and sclera. Invest. Ophthalmol. Vis. Sci. 1991. Vol. 32, № 8. P. 2244–2257.
- Stanworth A., Naylor E.J.Polarized light studies of the cornea. The isolated cornea. J. Exp. Biol. 1953.Vol. 30. P. 160–163.
- Penkov M.A., Kochina M.L. Method of diagnosing the pathology of intraocular pressure. Ophthalmological Journal. 1981. № 8. P. 476–479 (in Russian).
- Cogan D.C. Some ocular phenomena produced with polarized light. Arch. Ophthalmol. 1941. Vol. 25, № 3. P. 391–400.
- Cope W.T., Wolbarsht M.L., Yamanashi B.S. The corneal polarization cross. J. Opt. Soc. Am. 1978. Vol. 68, № 8. P. 1139–1141.
- Anderson K., El-Sheikh A., Newson T. Application of structural analysis to the mechanical behavior of the cornea. J.R. Soc. Interface. 2004. Vol. 1. P. 1–15.
- Kochina M.L., Kalimanov V.G. Investigation and modeling of the polarization-optical properties of the eye cornea in various states of extraocular muscles. Bionics of the intelligence. 2008. № 2 (69). P. 132–137 (in Russian).
- Shaffer R.N., Lieberman M. F., Drake M.V. Becker-Shaffer’s Diagnosis and Therapy of the Glaucomas. Mosby, 1999. 716 p. № 1. P. 34–35.
- Rao H.L., Senthil S., Garudadri C.S. Contralateral intraocular pressure lowering effect of prostaglandin analogues. Indian J Ophthalmol, 2014. Vol. 62. P. 575–579.