INTRAOCULAR PRESSURE AS A FACTOR AFFECTING CORNEAL HYSTERESIS MEASUREMENT
N. M. Sergienko, I. V. Shargorodskaya
The aim of the work was to investigate the influence of the intraocular pressure (IOP) on results of evaluation of the corneal biomechanical properties by the Ocular Response Analyzer (ORA).
Ten eyes of 10 patients with open-angle glaucoma were included in the study. Every eye was examined by ORA 3 times: after initial measurement 2 other measurements followed during artificially elevated IOP by ophthalmodi-namometer at 10 and 30 mm Hg. Though the examination of one eye was made during several minutes, there were significant changes of corneal hysteresis (CH) values in all patients at different IOP levels. The mean CH value in initial measurement was 8.51 ±0.4, then under the condition of IOP elevation at 10 and 30 mm Hg decreased to 4.7±0.3 and 0.67±0.3 respectively. In some eyes CH dropped to zero. At least, 2 causes influence the results of CH measurement by ORA: corneal biomechanical properties and IOP. Both factors should be taken into account for receiving the final result for clinical application.
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