REOOFTALMOGRAFIYA

From Big Medical Encyclopedia

REOOFTALMOGRAFIYA (Greek rheos a current, a flow + ophthalmos of eyes + grapho to write, represent; synonym oftalmoreografiya) — the method of a research of blood circulation in a choroid of an eye based on registration of change of the general resistance (impedance) during the passing through fabrics of electric current of average and high frequency. It is developed in 1964 by L. A. Katsnelson and in the next years found application in clinical and pilot studies hemodynamics of an eye (see) at various forms of pathology of an eye.

For R. use electrodes in the form of the contact lens imposed approximately, a reograf and the recorder, napr, the encephalograph. At R. apply electrodes in the form of a contact lens with the platinum or silver plates which are built in on its inner surface in the form of hemispheres 3 mm wide to receiving rather long record of eye pulse. The area of electrodes shall be not less than 20 mm 2 . At the correct fixing on an eye electrodes adjoin to its surface on 3 mm from a limb of a cornea, contacting, thus, to a projection of area tsiliarny or ciliary body (see). According to the principle reografiya (see) a research of a krovenapolneniye make in the zone located between electrodes therefore at contact of electrodes with an eyeglobe the krovenapolneniye shall be defined in vascular system of a ciliary body, however, considering a large number of an anastomosis between system of vessels of a ciliary body and choroid, it is possible to consider that at R. investigate blood circulation in a choroid of an eyeglobe.

Rubles make in a prone position. After introduction to the studied eye of 0,5% of solution of Dicainum impose electrodes. The patient is asked to watch up, at the same time the bottom edge of an electrode is brought to the lower conjunctival arch; then delay an upper eyelid and under it (the patient looks down) insert the upper edge of an electrode. During the research of the patient looks directly, his eyes shall be open that reduces their movement and promotes the best fixing of electrodes. Speed of the movement of a paper strip at a research is equal to 30 or 60 mm/sec. of R. carry out along with electrocardiography (see), using such synchronous research for the phase analysis. So, the average otstoyaniye of a reografichesky wave from the QRS complex of the electrocardiogram at persons at the age of 20 — 40 years is equal 0,17 ± 0,02 sec. and aged from 40 up to 60 years — 0,18 ± 0,13 sec. Unlike reoentsefalo-grams (see. Rheoencephalography ) at R. there is no dicrotic tooth. It can be explained with special conditions of blood circulation in an eye of the person at the expense of what at rather slow blood-groove in vessels of a choroid the second top of pulse wave arising during the closing of valves of an aorta is not shown.

There are descriptive and mathematical methods of interpretation reogramm (see. Reografiya ). The descriptive method based on assessment of a form of a reografichesky curve does not allow to define the nature of the studied process due to the lack of the dicrotic tooth defining various conditions of peripheral vessels.

From methods of mathematical processing by the most convenient there was a calculation of reografichesky coefficient for H. Jantsch which is made on

a formula R Q = (A*E w * 1000)/E*R,

where R Q — reografichesky coefficient, And — amplitude of a curve in mm; E w — a calibration impulse in ohm; E — a calibration impulse in mm; R — resistance between electrodes in ohm.

The Reografichesky coefficient is relative size and is expressed in per mille. The average value it normal makes 3 per milles.

Change of reografichesky coefficient indicates disturbance of a hemodynamics in the explored area: increase it as well as increase in amplitude of a reografichesky wave, characterizes a state, at Krom is available a vazodilatation, reduction — demonstrates to vasoconstriction. High test-sensitivity for indication of effect of vasodilating and vasoconstrictive drugs is established. In this regard reooftalmografichesky test was offered, at a cut the research is made before introduction of vasoactive means. It allows to define individual reaction of the patient to vasodilating or vasoconstrictive drug in each case. By means of R. it was established that at inhalation of pure oxygen there is expressed vasoconstriction of an eye, and at inhalation of mix of oxygen with carbon dioxide gas their clear expansion. The river matters for diagnosis of a carotid syndrome: at partial or full obstruction of an internal carotid artery considerable reduction of amplitude of a reografichesky wave on the party of defeat comes to light. High correlation between height is noted intraocular pressure (see) and the size of reografichesky coefficient, and also communication between a krovenapolneniye of a ciliary body and secretion of watery moisture. By means of R. changes of blood circulation of an eye were revealed at short-sightedness (see), to amotio of a retina (see), contusions eyes (see), uveites (see), acute and hron. processes on an eyeground.


Bibliography: Katsnelson L. A. Reografiya of an eye, M., 1977, bibliogr.; Naumenko A. I. and Skotnikov V. V. Bases of an elektropletizmografiya, JI., 1975, bibliogr.; In e t t e 1-h e i m H. Versuch einer Rheopletysmo-graphie des mensehlichen Auges, Albrecht v. Graefes Arch. Ophthal., Bd 172, S. 188, 196*7.


L. A. Katsnelson.

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