Optoacoustic monitoring of laser coagulation of the retina in the experiment in vivo
Abstract
The technology of control of laser action on the retina, based on the use of optoacoustic sounding, is discussed. A 丨ow-power probing laser with pulses of 7-10 ns generates acoustic waves in the retinal pigment epithelium, which are detected by an acoustic receiver located on a three-mirror lens placed on the cornea of the eye. The amplitude of the acoustic wave makes it possible to judge the value of the optical absorption coefficient at this point, a value determining the heating temperature of the region after the action of the therapeutic laser. To calculate the temperature field, a three-dimensional model of thermal conductivity is used, which allows determining the temperature distribution at any point during heating by the coagulator, and also after it is turned off. The experiment was carried out on 2 eyes of 1 rabbit of the chinchilla gray breed in vivo, it was planned to obtain 2 degrees of L 'Esperance coagulation according to the temperature distribution. In total, 17 out of 20 delivered at different points of coagulation were recognized as coagulants of the 2nd degree according to the classification of L 'Esperance.
About the Authors
N. A. Fedoruk
ФГБНУ «Научно-исследовательский институт глазных болезней»
Russian Federation
Russian Federation
A. V. Ardamakova
ФГБНУ «Научно-исследовательский институт глазных болезней»
Russian Federation
Russian Federation
A. P. Lytkin
ФГБОУ ВО «Московский государственный университет имени М.В. Ломоносова»
Russian Federation
Russian Federation
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Review
For citations:
Fedoruk NA, Ardamakova AV, Lytkin AP. Optoacoustic monitoring of laser coagulation of the retina in the experiment in vivo. Ural Medical Journal. 2018;(6):141-144. (In Russ.)
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