Received: 19 November 2019; Published on-line: 21 February 2020
Assessment of the efficacy of eyeball local vacuum compression with a new suction cup for impedance oculopneumoplethysmography depending on anatomical parameters of the eye
A.G. Kovalchouk1, I.V. Potapenko2
1SI “The Filatov Institute of Eye Diseases and Tissue Therapy of the National Academy of Medical Sciences of Ukraine”; Odesa (Ukraine)
2 Odessa National I.I. Mechnikov University; Odesa (Ukraine)
TO CITE THIS ARTICLE: Kovalchouk AG, Potapenko IV. Assessment of the efficacy of eyeball local vacuum compression with a new suction cup for impedance oculopneumoplethysmography depending on anatomical parameters of the eye. J.ophthalmol.(Ukraine).2020;1:57-67. http://doi.org/10.31288/oftalmolzh202015767
The relationship between the eyeball size and convexity of its anterior part and the efficacy of local vacuum compression of the eye performed using a new design suction cup for impedance ophthalmopneumoplethysmography was studied. Based on the mathematical modeling of the geometric shape of the anterior segment of 75 eyes obtained by ultrasound biomicroscopy examination, it was found that the horizontal meridian curve of the anterior eye segment with a base diameter of 16.00 mm could be best approximated by a hyperbola. The surface area under the new suction cup with an inside diameter of about 16.5 mm was calculated using the formula for the segment surface area of a hyperboloid of revolution. It was determined by the convexity of the anterior part of the eye and varied from 247.3 to 271.4 mm2. The conversion coefficient of the level of applied vacuum to the level of IOP rise, calculated on the basis of individual combinations of the surface area of local vacuum compression and the eyeball size, was on average 0.83 ranging from 0.44 to 1.33. Using an individual conversion coefficient according to eyeball anatomical parameters will make it possible to measure diastolic ocular perfusion pressure during impedance OPPG with high sensitivity and accuracy.
Keywords: impedance ophthalmopneumoplethysmography, mathematical modeling of the shape of the anterior eye, intraocular pressure, ocular perfusion pressure, local vacuum compression of the eyeball, ultrasound biomicroscopy
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The authors did not receive funding when conducting research and writing an article. No Conflict of Interest is declared.