OFTALMOSKOPIYA (grech, ophthalmos of eyes + skopeo to consider, investigate) — the method of an endoscopic research allowing to estimate a condition of internal covers of an eye. The Lake
is the cornerstone examining under increase in this or that site of an eyeground lit with a bunch of light rays. To observe a sharp image of its details it is possible on condition of coincidence of the line of a zasvet to the line of observation.
The aberrations found at O. not always testify to a disease of an eye. Quite often changes of an eyeground are a consequence of a number of the general diseases of an organism (an idiopathic hypertensia, a diabetes mellitus, diseases of blood, etc.) or damages of a brain (at tumors, injuries inflammatory and other diseases), and its survey helps to specify the diagnosis (see. Eyeground ). Oftalmoskopichesky diagnosis is carried out at an ophthalmosurgery (during the definition of localization of ruptures of a retina, location of foreign bodys, tumors and so forth).
At impossibility to see an eyeground directly (because of opacification of the refracting environments) resort to an autooftalmoskopiya (see. Entoptichesky phenomena ).
Depending on the optical scheme of the ophtalmoscope the researcher can observe the lit site of an eyeground or turned (O. in the return look), or in true position (O. in a direct look).
Oftalmoskopiya in back m a look allows to see in one step the extensive area of an eyeground therefore it is applied to the general survey of an eyeground. It is carried out by means of the mirror ophtalmoscope representing a concave mirror with the handle; in the center of a mirror there is an opening for observation. At O. use collective magnifying glasses. The mirror is kept at arm's length apprx. 50 cm, and a magnifying glass in 7 — 8 cm, from the eye investigated. A light source — the 100 — 150 W electric bulb with a transparent flask have behind the patient at the left and several. The doctor by means of a mirror, a cut it holds in the right hand, sends a beam of light and as soon as the pupil begins to shine the pink light reflected from an eyeground to the studied eye establishes the magnifying glass which is in his left hand before the studied eye. The distance from an eye to a magnifying glass is selected taking into account length of its focus. The valid turned image of an eyeground at the same time forms between a magnifying glass and an eye of investigating. Survey of an eyeground demands a certain skill. For the beginning O. it is complicated because of a lid reflex owing to reflection of beams from a front surface of a cornea of investigated.
For measurement of objects of an eyeground, assessment of its relief and the nature of visual fixing use the so-called bezrefleksny O. in the return look which is carried out by means of the big bezrefleksny ophtalmoscope (BO-58). Thanks to existence in this device of binocular system of observation stereoscopic O.'s carrying out in the return look is possible. Refer impossibility to explore the periphery of an eyeground to bezref-leksny O.'s shortcomings.
The direct ophthalmoscopy is applied to more careful studying of details of an eyeground. Use the electric manual ophtalmoscope (EO-61). He creates significant increase in of-talmoskopiruyemy details of an eyeground (by 8 — 16 times), allows quantitatively (in dioptries) on required refocusing to estimate degree of roughnesses of a relief of an eyeground: distinction in 3,0 dptr at transfer into linear measures makes 1 mm. Direct O.'s equipment is simpler, than the return. The doctor, having placed the ophtalmoscope before the eye, sends the beam of light proceeding from the device to an eye of investigated and gets closer to him on distance to 1 — 2 cm. At survey of the right eye of the patient it is more convenient to oftalmoskopirovat right, and at survey of left — the left eye. Rotating a refraction disk of the ophtalmoscope to the right, to the left, find the direction, in Krom it is necessary to korrigirovat system the observer — the device — the studied eye.
The biomikrooftalmoskopiya — O. in a direct view with the help of a slit lamp (ShchL-56) is very informative. It became possible after introduction to optical system of a slit lamp strong (— 60 dptr) a biconcave lens (apply a biconvex lens to the same purpose less often); the most perspective is the plano-concave system installed after anesthesia directly approximately (Goldmann's lens).
At an oftalmoskopichesky research (in red, yellow, flavovirent, blue, purple and redless light (oftalmokhromoskopiya) it is possible to catch details of an eyeground, invisible at usual lighting. So, in redless light the area of a macula lutea, and in flavovirent — vessels, hemorrhages etc. is especially well visible.
In recent years with the advent of a retinofot there was an opportunity not only to examine, but also to photograph an eyeground.
Devices for an oftalmoskopiya
The eye mirror offered by G. Helmholtz in 1851 was the first device for observation of an eyeground. It consisted of 3 — 4 glass plates imposed at each other and reflecting in an eye light from a candle. In 1899 Torner (W. Tyogpeg) formulated the principle of obtaining the bezrefleksny image, and on its basis in 1911 Gul-lstrand created the first stationary bezrefleksny ophtalmoscope. Then later were released by Cari Zeiss (GDR) and received practical application in clinic the mirror ophtalmoscopes representing a concave mirror with an opening in the center. The mirror reflects in an eye of the patient light from a desk lamp or the desktop ophthalmologic lighter. The ophtalmoscope mirror 03-4, released in the USSR (fig. 1), consists of 2 mirrors — bent for O. and flat for a skiaskopiya established in one frame. In the center of a mirror there is an opening with a diameter of 3 — 4 mm for observation. Magnifying glasses — 13 and 20 dptr, giving increase about 5 and 3 times are entered into its set.
In the 30th 20 century for O. in a direct look began to release manual electric ophtalmoscopes. The optical system placed together with a filament lamp in the handle of this device projects the image of thread of a lamp on the periphery of a cornea; the inspection hole of the ophtalmoscope is located at the level of the central area of a cornea. For correction of an ametropia of the patient and the doctor in the ophtalmoscope there are refraction disks with a set of lenses. Food of a lamp is carried out from the alternating current main through step-down transformer. The majority sovr, manual electric ophtalmoscopes allows to conduct a research in not darkened room and without medicamentous mydriasis. Also collective magnifying glasses for O. in the return look are included in the package. In the USSR in addition to the manual electric ophtalmoscope (EO-61) the manual electric OP-2 ophtalmoscope (fig. 2) is issued. The device is supplied redless and orange with light filters; it provides correction of an ametropia from +30 to — 25 dptr. The size of the lit field can be changed by means of diaphragms, including and a diaphragm for focal lighting. There is a crack for assessment of a relief of an eyeground. The nozzle for a slit lamp with increase by 5 times for a research of transparent environments of an eye, and also a diafanoskopichesky nozzle is included in the package. According to A. M. Vodovozov's proposal O. allowing to carry out in the light of various spectral structure is issued oftalmokhromoskop, for what in the device there are 6 replaceable light filters increasing picture contrast of various elements of an eyeground. Electric manual ophtalmoscopes «Cari Zeiss — Yena», «Heine» (Germany), «Keeler» (England), etc. were widely adopted. The universal manual ophtalmoscope released in the USSR with a slit lamp and fiber light guides of OBCp-Ol (fig. 3) provides high intensity of lighting with cold light and allows to conduct a research in natural this world, with redless and orange light filters and a fluorescent angioskopiya. The device gives the chance to carry out a polarizing oftalmoskopiya by means of the rotary polarizing filters increasing contrast of structural elements of an eyeground and is fuller eliminating light reflexes. The manual slit lamp, direct and curved diafanoskop, a magnifying glass + 13 dptr is included in the package.
In the USA, Germany, Japan the manual ophtalmoscopes with autonomous food which are not demanding inclusion in the power supply network are issued. They are used in chambers for a research of bed patients and at departure on places where there is no power supply network. Food is carried out from the batteries or accumulators which are built in together with a tiny lamp in the handle. Oculus (Germany) releases vizuskop — the manual electric ophtalmoscope supplied with grids and test objects for a kalibrometriya and another dimensions on an eyeground, definitions of parafovealny fixing, measurement of a refraction, an astigmatism and the direction of axes of an eye. The device for pleoptichesky diagnosis and treatment of an amblyopia is included in the package of the ophtalmoscope. In the USA, England, Japan the nalobny binocular ophtalmoscope releasing at O. hands of the doctor for manipulations is issued. It provides a stereoscopic research of an eyeground in the return view with the help of an oftalmoskopichesky magnifying glass.
Along with manual stationary ophtalmoscopes with the increased increase and a big field of sight at more perfect elimination of reflexes are issued. They are mounted on coordinate little tables with horizontal and vertical motions and are established together with support for the person on tool tables. Ophtalmoscopes are supplied with fixating points for installation of the direction of a look of the patient; food is provided through step-down transformer from the alternating current main. Gullstrand's ophtalmoscope is a prototype of the majority sovr, stationary ophtalmoscopes. The stationary big bezrefleksny ophtalmoscope B 0-58 released in the USSR provides a monocular research with increase in 10,5; 21 both 29 times and a stereoscopic research with increase in 12 and 16 times by means of binocular adjustment. Aiming on sharpness in the range from — | — 18 to — 30 dptr at a monocular research and from + 16 to — 25 dptr at binocular is carried out by focusing of eyepieces. For measurement of elements of an eyeground there are replaceable eyepieces with a grid, test objects and the micrometric device reducing in one appearing doubled image. The ophtalmoscope is supplied with the removable refraktometrichesky node allowing to measure a refraction ranging from — 14,5 till 4-19 dptr, and also the device for diagnosis and treatment of an amblyopia with excentric fixing. For O. also a number of stationary stereoophtalmoscopes of foreign firms is used.
For photography of an eyeground retinofota are issued, to-rye represent the stationary devices installed on tool little tables. They allow to carry out shooting on a standard color and black-and-white film 35 mm wide, provide bezref-leksny pictures at exposure time about several milliseconds. Devices are supplied, except a halogen lamp for observation and aiming, with a powerful flashlight valve with several steps of energy of flash for photographing. For a fluorescent angiography of an eyeground offices of firm «by Carl Zeiss — - Jena» — retinofot and «Stereooftalmoskop-110» are used. The Japanese firm «Canon» releases the camera for shooting of an eyeground without mydriasis. An eye is lit with the infrared beams which are not causing narrowing of a pupil. The television camera mounted on the case of the device provides the visible black-and-white image of an eyeground on the screen of the monitor, on Krom aiming on sharpness is made. Shooting is conducted in visible light on a usual color or black-and-white film at flash of a flashlight valve. The corner of the represented field makes 45 °. In Japan also hand-held camera for photography of an eyeground is issued. In the USSR the makulotester polarizing (MTP-2) intended for a research of a macula lutea of a retina is issued.
Bibliography: Arkhangelsk V. N. Morphological bases of oftalmoskopichesky diagnosis, M., 1960; Veynberg V. B. and With attar ov D. K. Optika of light guides, JI., 1977; A. M. Oftalmokhromoskopiya's (Atlas) Water carriers, M., 1969; V. V. Wolves, A. I. Gorban and D and l and and sh-in and l and O. A. Clinical trial of an eye by means of devices, L., 1971; The Reference book on ophthalmology, under the editorship of E. S. Avetisov, M., 1978; T and m and r island and R. M. Polarizing method of a research of an eyeground and front department of an eye, Medical technician, No. 6, page 10, 1979; Tamarova R. M., Gorbov-tsova G. I. and Mishustin V. V. Manual OP-2 ophtalmoscope, in the same place, No. 4, page 23, 1975; Yu t of t of e A., JI e of m to e JI. and Krause W. The fluorescent color photo of an eyeground by means of the device for photography of a retina of «Retinophot» of N / p «Karl Tseyss Yen», Yenskoye obozr., No. 1, page 31, 1972; Der Augenarzt, hrsg. v. To. Velhagen, Bd 1, S. 559 u. a., Lpz., 1969, Bibliogr.
B. B. Wolves; P. M. Tamarova (tekhn.).