X-ray of the eye. How to develop X-ray vision? Skeletal anterior ocular radiography techniques

09.07.2020

The organ of vision consists of the eyeball, its protective parts (orbit and eyelids) and the appendages of the eye (lacrimal and motor apparatus). The eye socket (orbit) is shaped like a truncated tetrahedral pyramid. There is a hole at the top for optic nerve and the orbital artery. At the edges of the optic opening, 4 rectus muscles are attached, the superior oblique muscle and the muscle that lifts upper eyelid... The walls of the eye sockets are composed of many facial bones and some bones of the cerebral skull. From the inside, the walls are lined with the periosteum.

The image of the eye sockets is available on the general X-rays of the skull in frontal, lateral and axial projections. In the picture in frontal projection, with the naso-chin position of the head in relation to the film, both eye sockets are visible separately, and the entrance to each of them is very clearly distinguished in the form of a quadrangle with rounded corners. Against the background of the orbit, a light narrow upper orbital sheath is determined, and under the entrance to the orbit there is a round opening through which the infraorbital nerve exits. On the lateral images of the skull, the images of the orbits are projected onto each other, but it is not difficult to distinguish between the upper and lower walls of the orbit adjacent to the film. On the axial radiograph, the eye socket shadows are partially superimposed on the maxillary sinuses. The opening of the optic nerve canal (round or oval shape, diameter up to 0.5-0.6 cm) is imperceptible in the survey images; to study it, a special photograph is taken, separately for each side.

An image of the sockets and eyeballs that is free from the superposition of adjacent structures is achieved on linear tomograms and especially on computer and magnetic resonance tomograms. It can be argued that the organ of vision is an ideal object for AT due to the pronounced differences in the absorption of radiation in the tissues of the eye, muscles, nerves and blood vessels (about 30 HU) and retrobulbar adipose tissue (-100 HU). Computed tomograms allow obtaining an image of the eyeballs, vitreous body and lens in them, the membranes of the eye (in the form of a total structure), the optic nerve, the orbital arteries and veins, the muscles of the eye. For the best display of the optic nerve, the cut is made along a line connecting the lower edge of the orbit with the upper edge of the external auditory canal. As for magnetic resonance imaging, it has special advantages: it is not accompanied by X-ray irradiation of the eye, makes it possible to examine the eye socket in different projections and differentiate blood accumulations from other soft tissue structures.

New horizons in the study of the morphology of the organ of vision opened ultrasound scan... The ultrasound devices used in ophthalmology are equipped with special eye sensors operating at a frequency of 5-15 MHz. In them, the "dead zone" is reduced to a minimum - the nearest space in front of the piezoelectric plate of the sound probe, within which echo signals are not recorded. These sensors have a high resolution - up to 0.2 OD mm in width and front (in the direction of the ultrasonic wave). They make it possible to measure various structures of the eye with an accuracy of 0.1 mm and to judge the anatomical features of the structure of biological media of the eye on the basis of the amount of attenuation of ultrasound in them.

Ultrasound examination of the eye and orbit can be carried out by two methods: Α-method (one-dimensional echography) and B-method (sonography) In the first case, echo signals corresponding to the reflection of ultrasound from the boundaries of the anatomical environments of the eye are observed on the oscilloscope screen. Each of these boundaries is reflected on the echogram as a peak. An isoline is normally located between individual peaks. Retrobulbar tissues produce signals of various amplitudes and densities on a one-dimensional echogram. An image of the acoustic section of the eye is formed on the sonograms.

In order to determine the mobility of pathological foci or foreign bodies in the eye, sonography is performed twice: before and after a quick change in the direction of gaze, or after a change in body position from vertical to horizontal, or after exposure to a foreign body magnetic field... Such kinetic echography allows you to determine whether a lesion or a foreign body is fixed in the anatomical structures of the eye.

On survey and sighting radiographs, fractures of the walls and edges of the orbit are easily determined. The fracture of the lower wall is accompanied by darkening of the maxillary sinus due to hemorrhage into it. If a fissure in the orbit penetrates the paranasal sinus, air bubbles in the orbit (orbital emphysema) may appear. In all unclear cases, for example, with narrow cracks in the walls of the orbit, CT is helpful.

17-05-2012, 21:14

Description

The value of the technique, its physical essence

Among the severe injuries to the organ of vision, one of the main places is occupied by wounds, which accompanied by penetration foreign body inside the eyeball... X-ray methods allow, as a rule, to detect such a fragment, determine its size and shape, establish its location and, ultimately, outline the most rational way to remove a foreign body from the eyeball or from the orbit.

Physically, the essence of the study is determined by the unequal absorption of X-rays by various substances and tissues. By changing the voltage on the X-ray tube, you can vary the so-called hardness of X-rays... In ophthalmology, "soft" beams and "medium hardness" radiation are used for diagnostic purposes.

For "soft" rays, the tissue of the eyelids and eyeball is already a noticeable obstacle that forms a pronounced shadow. With this mode of operation, the roentgenological soft tissue fragments of glass, stone, aluminum and other relatively light materials (over 1.0 mm in length), as well as the smallest particles of heavier metals. Unfortunately, this radiation is almost completely blocked by the bones of the skull. Therefore, it is possible to realize its advantages only within the framework of a special research technique (skeletal radiography). X-rays of "medium hardness" are able to penetrate bones and give a shadow pattern of the skull structure on the screen or on film. Correctly selected tension should be considered such that not only compact bone masses (base of the skull, zygomatic bone, entrance to the orbit, etc.), but also relatively thin structural formations (wings of the main bone, back of the sella turcica, etc.) .d.). The optimal mode is set separately for each projection. He must provide best conditions to identify the shadows of fragments made of iron and copper alloys 1-3 mm in length, typical for eye trauma.

The search for a foreign body can be carried out not only by fixing the image on film (X-ray) and by direct observation of the shadow picture on a fluorescent screen (X-ray). There is also a third technique - observing the shadow of the splinter by the wounded himself. against the background of the luminescence of the dark-adapted retina in the X-ray beam ("autorentgenoscopy"). However, both conventional fluoroscopy and auto-roentgenoscopy, for various reasons, were not included in ophthalmological practice. The creation in recent years of devices that many times increase the contrast and brightness of the image on the screen - electron-optical amplifiers - may bring fluoroscopy to the fore in ophthalmology. But so far these amplifiers are available only in the largest institutions, and the main technique is still fluoroscopy, the various versions of which will be discussed below. Recall that a negative image is formed on the film during X-ray. Therefore, unlike an X-ray picture, denser formations, including foreign bodies, look like lighter areas against a dark background.

So, the first clinical problem that an X-ray study is designed to solve is search for foreign bodies in the area of \u200b\u200bthe eye and orbit... Such a survey radiography, if the fragment is large, will lead to its detection already using conventional (skeletal) images. If the foreign body has poor contrast (very little, made of relatively light materials), then the task of a survey study is successfully resolved only with skeletal radiography.

The division of the method into these 2 main groups, which differ significantly in the technique of shooting, retains its significance at the second stage of the study - when performing localized radiography. Her goal is determination of the localization of the detected fragment (outside the eye, and if inside the eyeball - then where exactly) - with an accuracy sufficient for typical cases of damage. There are many different techniques and their varieties. In the relevant section, we will focus on the main options for X-ray examination, which allow taking into account the specific features of the damage to the eye by a fragment.

The third stage - clarifying X-ray diagnostics - designed to answer a number of additional questions about the location of fragments in particularly difficult cases. And here, naturally, both "skeletal" and "skeletal" images are used.

In both research options, one and the same equipment is used, the "heart" of which is x-ray tube.

In an X-ray tube, the radiation source is a small section of the beveled surface of the metal anode - focus of the tube on which the electron beam hits... Naturally, the rays emerging through the window in the tube body have the character of a diverging beam. The shadow image of the object formed by such a beam on the film will inevitably be enlarged. Figure: 125

Figure: 125. 3 radiography schemes (I, II and III) of the same object.
1 - image; 2 - object; 3 - tube focus.

illustrates the emergence of such projection magnification.

The following rule follows from the figure: The closer the subject is to the film, or the longer the tube-to-film focal length, the lower the projection magnification, and vice versa.

Knowledge of this rule helps in orientation with wounds with multiple fragments, allows, looking at the pictures, to imagine the position of the wounded person's head during radiography, makes it possible to calculate the exact magnification of the pictures (according to the formula below).

If denoted by the letter a - the size of the image; letter F - focal length "tube - film"; letter b is the diameter of the object and c is the distance from the object to the film, then

Image quality is largely determined by the degree of "blurring" of the contours of the X-ray image... Light a lamp without a shade. Look at the size of your wrist shadow if you hold your hand against the opposite wall, in the middle of the room, and near the lamp. You may have noticed that as you move your hand away from the screen-wall, the contours of your fingers become more and more blurry, out of focus. Exactly the same relationship takes place in radiography, since the area of \u200b\u200bfocus of conventional tubes is large enough for the formation of penumbra (Fig. 126).

Figure: 126. Penumbra formation diagram on radiography.
1 - focus area; 2 - object; 3 - film; 4-object shadow; 5 - ring of unsharp penumbra.

As for the well-founded desire to use the maximum focal length (teleradiography), it is not always acceptable for ophthalmological purposes. At first, the exposure of the picture grows in proportion to the square of the "tube-film" distance, and it is difficult to ensure complete immobility of the eye for a number of seconds. Secondly, with the existing measurement technique on radiographs, to localize fragments in the eye area, one has to use a standard focal length (60 cm).

Very promising use "Sharp-focusing" tubes... Conventional tubes with a focus of 3X3 mm give an unsharp shadow edge of 0.5 mm. Reducing the focus size to 0.3x0.3mm provides such a low blur edge of the shadow that pictures can be taken even with direct magnification by moving the film away from the subject. Twofold increase fully preserves or even improves diagnostic capabilities for the smallest foreign bodies. For ophthalmic purposes, such tubes are truly irreplaceable, but they are still available in very limited quantities.

The second source of fuzziness of the contours of the details of the X-ray image on the film is the scattering of x-rays on an object... Those rays that hit the film from all sides lightly illuminate it, and the contrast between the shadow areas and the areas of enlightenment is erased. One of the effective means of dealing with scattered radiation is the previously mentioned tube, which limits the beam of rays. It is selected in such a way that in the area of \u200b\u200bthe picture at the selected focal length, those objects remain, the study of which is of direct interest for diagnosis. In tubes with a variable orifice size, this is achieved by a metered opening of the diaphragm under the control of optical pointers that give a light outline on the surface of the object.

In general radiology, all kinds of "Hoods" and "gratings" that cut off a significant part of the scattered radiation from a cassette tape. However, they are of little use for ophthalmic purposes, since they require lengthening the exposure and reduce the accuracy of calculations.

The third reason due to which the shadows of intraocular debris can become blurry and difficult to detect on film is object mobility at the time of the shot... The head of the wounded man, the eyeball, and, finally, the shard itself (in liquefied vitreous). It is not difficult to immobilize the patient's head (with sandbags, tapes, clamps, etc.). It is much more difficult to keep the eye still. Therefore, for ophthalmic purposes, it is desirable to choose the most powerful X-ray apparatus operating at exposures of the order of tenths of a second.

With any laying of the head of the wounded it is necessary to fix his gaze on a well-defined, clearly visible object (even if vision is preserved in only one eye). Recommendations such as “look straight ahead” do not provide the proper immobility of the eyeball.

A fragment moving in the eye can be displaced at the time of the photograph if the X-ray is taken immediately after placing the wounded in a new position or immediately after turning the eye to a new position. therefore it is advisable to perform radiography after 40-60 seconds after giving the head and eye of the wounded the desired position.

Finally, fourthly, the "smearing" of the shadow of the fragment in the picture may appear due to vibrations of the X-ray tube at the time of X-ray... This should not be forgotten. A blurred shadow can lead to the fragment not being recognized, this is understandable. But diagnostic errors are possible even if the optimal shooting conditions are observed - when the quite sharp shadow of a small foreign body is not contrasted due to the projection onto the intense shadow of some bone mass or onto the shadow of another, larger fragment. By changing the direction of the X-ray path (i.e., by reasonably changing the wounded person's position or just the position of the eyeball), as a rule, it is possible to bring the shadow of the fragment into the area with respect to the illuminated background.

Known effect on foreign body image clarity has a shard shape... The intensity of the shadow of a linear or lamellar fragment depends on how the length of the foreign body is located - along or across the path of X-rays. A snapshot along the length of the fragment gives, although smaller in area, a more contrasting shadow. It is for this reason that such fragments are often not visible in all images, but only in one projection. However, the strict orientation of the length of the fragment along the X-ray path is a very rare phenomenon. More often the linear splinter is in some kind of "oblique" position. In this case, the difference between the pictures in the contrast of its shadow will be weak. But at the same time, both the shape of the fragment and its true dimensions will be hidden from the observer.

It was mentioned above why the shadow of a foreign body in the eye area may not be detected on radiographs. But there are errors of the opposite nature, when a false "shadow of a foreign body" (artifact) is contoured on the film in the absence of a fragment. Artifacts differ from the shadows of foreign bodies by too much clarity of the contour and usually the correct (round) shape.

There are several sources of such artifacts:

and) defect in fluorescent screens glued into cassette lids;

b) debris falling between the film and the cassette screen;

in) defects in the emulsion of the film itself; d) non-processing of a film section with reagents due to fatty spots on its surface, settled debris, air bubbles, etc.

If the images are taken without screens - as with skeletal radiography, the source of artifacts can only be the reasons mentioned in paragraphs "c" and "d". The completely random nature of their appearance makes it possible to reliably differentiate true shadows from false ones by a simple technique: doubling the film that is inserted into the envelope. If shadows are present on both films and coincide when the films are superimposed on each other, then we are really talking about a fragment in the eye area. If the shadow is visible only on one of the films or on both, but when the films are combined, the shadows do not match, they can be ignored: these are artifacts.

The situation is different with skeletal images.... The first two of the above reasons for the formation of artifacts will also act when doubling films in a cassette. Therefore, it is necessary to select such cassettes, the screens of which have been checked by control pictures and do not contain defects. If, for one reason or another, a picture containing a "suspicious shadow" was made on an unchecked cassette, it must be repeated with the same installation, but using a different cassette. Under these conditions, the artifact will not appear in the same place.

Orbit images in different projections should not be done on the same rechargeable cassette... If under these conditions the cassette screen gives an artifact, a complete illusion of a foreign body appears (a clear shadow in all projections). True, here you can also find the false nature of the shadows: you need to combine films with each other in front of the negatoscope (edge \u200b\u200bto edge). If the "shard's shadows" match exactly, this is an artifact that appears in a very specific place on the film itself, and not in the eye socket, which is depicted on the film.

As you can see, the quality of X-ray diagnostics of foreign bodies in the eye largely depends on the equipment of the office and the qualifications of the X-ray technician... Therefore, it is useful to get acquainted with the capabilities of your equipment medical institution and find out how experienced the technical staff is in taking "eye" pictures. It may turn out that at first, the X-ray technician will facilitate in some way your work on the study of the method. But it may also be so that you will have to lead some stages of his work from the very beginning. This concerns, first of all, the correct execution of the styling required for X-ray images of the eye socket in various projections.

Plain radiography

The indications for the production of this first stage of the study are as follows:

and) fresh perforated wound of the eyeball;

b) orbital injury;

in) contusion of the eye and orbit;

d) inflammatory and degenerative changes in the eye, which may be associated with the presence of an intraocular fragment (recurrent unilateral iridocyclitis, siderosis or chalcosis, unilateral cataract of unknown etiology, etc.);

e) traces of an old perforated wound accidentally found in a "healthy" eye.

The study begins with skeletal images in different projections... Having found a shadow of a rather large fragment in such images, this first stage of work should not always be considered completed. In case of gunshot wounds (less often, with industrial injuries), there may be other, smallest fragments in the eye, which can be detected only with the help of skeletal overview images. This should always be remembered.

Both skeletal and non-skeletal panoramic images must be executed twice: they start X-ray diagnostics; they are produced and by the time of completion inpatient treatment wounded. Unfortunately, before discharge after a successful operation, survey images are rarely taken. Sometimes the shard breaks apart when removed. The large part is removed, the small part remains. Inattentiveness in such a case can nullify the successful outcome of the operation.

Plain skeletal radiography

Skeletal radiography of the orbit area can be carried out in a wide variety of positions of the wounded: sitting or lying on your stomach, on your side, on your back. If for industrial injuries with a typical isolated injury to the eyeball, the position of the wounded is not significant, then for gunshot wounds the choice of the most sparing variant of it begins to play a serious role in the technique of radiography. This takes into account such circumstances as the lack of mobility of the wounded, the presence of concomitant injuries to the limbs, chest, abdomen and face, as well as the extent of the injury to the eye, threatening the loss of its contents.

Apparently, now no one has any doubts that lying on the stomach (face down) is the least successful... The positions "lying on the side" and "lying on the back" are realized in case of any injury, including those of stretcher wounded. Therefore, they should be preferred for severe injuries. Seated shots are very handy when it comes to walking wounded. So, there are no universal, "best" styling; out of many possible options, you need to be able to choose the one that would meet the capabilities of the X-ray room and, on the other hand, individual characteristics damage.

X-ray of the skull in case of eye damage by fragments, as a rule, they try to produce in such positions so that the resulting bone pattern on the radiograph is easily deciphered, and the eye is projected into the image area, relatively free from the shadows of massive bone formations. These requirements are met by a number of skull projections, three of which are considered to be the main ones: anterior (frontal), lateral or profile, and semi-axial (Fig. 127, A-B).

Figure: 127. Diagram of the three main layouts for skeletal radiography of the orbital region (view from both sides - I and II).
1 - X-ray tube; 2 - cassette with film; 3 - stand. Explanation in the text.

Taken in pairs, these projections are perpendicular to each other, which makes it possible to visually evaluate the relative position of the shadow of a foreign body and individual elements of the facial skull in a system of three rectangular coordinates: the depth of the fragment penetration, the level of its location (up or down) and the degree of lateral deviation (to the temple or to the nose).

Of these three skeletal projections, the lateral image has the highest resolution for small fragments.

Known difficulties arise only with the smallest fragmentslying in the posterior third of the eyeball and projecting onto the rather dense shadows of the temporal edges of the orbits (Fig. 128, A).

Figure: 128. Schematic of a lateral radiograph of the orbital area with correct (A) and incorrect (B) placement.
1 and 2 - line of the roof of the eye socket; 3-Turkish saddle; 4 - poorly differentiated line of the bottom of the orbit; 5 and 6 - outer edges of the entrance to the orbit; 7 and 8 - the shadow of the frontal-main processes cheek bones; 9 and 10 - frontal-zygomatic sutures; 11 - the shadow of the nasal bone; 12 - frontal sinuses; 13 and 14 - maxillary sinuses; 15-main sinus; 16 - cells of ethmoid sinuses; 17 - outline of an approximate projection ("zone") of the eyeball; shaded areas free from the imposition of massive bone shadows.

In such cases, it makes sense to take pictures with not strictly lateral stacking (the head should be slightly turned towards the cassette or away from it). Then the shadows of both frontal-main processes of the zygomatic bones diverge and, as it were, reveal a part of the posterior segment of the eyeball (Fig. 128, B).

The front image in the so-called "kissing" position, when the wounded person touches the cassette with his chin and the tip of his nose, has a slightly lower resolution.

Affected by an increase in the projection increase in the shadow of a foreign body in the eye area (from 5 to 10% compared to the lateral view), as well as the shading effect of the occipital bones and the entire mass of the cerebral skull (Fig. 129).

Figure: 129. Schematic of anterior radiographs of the orbital area.
1 and 2 - the contours of the entrance to the eye sockets; 3 - nasal passages; 4 and 5 - frontal sinuses; 6 and 7 - maxillary sinuses; 8 and 9 - shadows of the zygomatic bones; 10 and 11 - frontal-zygomatic sutures; 12 and 13-approximate projection ("zone") of the right and left eyeballs; 14 and 15 - shadows of the wings of the main bone.

The greatest difficulties are encountered when searching for foreign bodies when analyzing radiographs in semi-axial projection... A relatively slight tilt of the head anteriorly (at an angle of 25-30 °) leads to the fact that approximately the back half of the eye is covered with a massive shadow upper jaw (fig. 130).

Figure: 130. Diagram of a semi-axial radiograph of the orbit area.
1 and 2 - outer borders of the eye sockets; 3 and 4 - the inner borders of the eye sockets; 5 - the shadow of the septum of the nose; 6 - the shadow of the frontal bone; 7 and 8 - frontal sinuses; 9 and 10 - maxillary sinuses; 11 - the front contour of the shadow of the upper jaw and zygomatic bone (12 and 13 - the same contour with a smaller inclination of the head at the time of the picture); 14 - shadow of the alveolar processes; 15 and 16 - the contours of the approximate projection ("zone") of the eyeballs (shaded areas, usually free from the imposition of intense bone shadows).

You can try to bring out the shadow of the fragment outside the bone contours using the deviations of the eye (but not up and down, as in a side view, but to the right - to the left).

With a semi-axial image, the eye is removed from the film by 10 cm.This leads not only to an increase in projection magnification (up to 20% with a standard F \u003d 60 cm), but also to the corresponding enhancement of blur shadows of fragments... Apparently, the semi-axial projection, which has a number of advantages over the front, should still play an auxiliary role in most cases of X-ray diagnostics.

After the patient is correctly positioned (or seated in the desired position) and the required immobilization of the head is achieved, it is necessary to center the X-ray tube on the eye area, which is set in advance at the desired focal length. The difficulty in centering is that the wounded eye is placed closer to the film and an opaque skull separates it from the tube. Under these conditions, the most accurate "centralizer" mounted on a tube or inside a tube turns out to be ineffective. Fortunately, calculations show that with a standard focal length of 60 cm, a noticeable error (2 mm) in determining the coordinates of an intraocular fragment can occur only with significant lateral displacements of the tube from the correct position (about 5-10 cm). And such a pronounced inaccuracy in the position of the tube can be easily detected by simple observation from two different positions (see Fig. 127) and promptly eliminated. For a rough assessment of the X-ray picture in the area of \u200b\u200bdamage, especially when there is evidence of injury to both orbits, it is advisable to center the tube with anterior and axial images not on any particular eye, but approximately at the middle of the interpupillary distance (see Fig. 127, A and B , indicated by a dotted line). Of course, you also need to take a tube with a wider outlet.

With an eye injury, especially a gunshot, a wounding splinter can go far beyond the orbit... Pictures on a small cassette (13X18 cm) help to detect a fragment if it lingers in the paranasal sinuses, pterygopalatine fossa, in the central parts of the cranial cavity. But the peripheral parts of the middle and posterior cranial fossa may not be projected onto such a film. To exclude the unpleasant possibility of viewing an intracranial foreign body, at least one of the survey images of the eye sockets (preferably in the front projection) is made on a sufficiently large film (18X24 cm).

X-ray examination of the wounded usually begins with a combination of such a picture with a side one. If it is difficult to determine from these images whether the fragment is in orbit or has gone beyond its limits, a semi-axial image must be taken. Since the contours of the orbit are well defined on it, it helps to establish or exclude the intraorbital localization of a foreign body.

When in the pictures taken in all projections, the shadow of a foreign body is located in the area of \u200b\u200bthe eyeball, there are reasons to proceed to the second (localization) stage of the study. The contours of these "suspicious" areas were shown in Fig. 128, 129 and 130.

If the shadow of a foreign body is superimposed on this area in only one of the images, then the fragment is located outside the eye. This is where the "skeletal" survey X-ray examination ends.

Do some exercise.

Exercise 1. Practicing the positioning of eye wounded for skeletal radiography in various projections. This exercise can be performed outside of the X-ray room (for example, on an operating table). You must have two unloaded cassettes (13X18 cm and 18X24 cm) or corresponding pieces of thick cardboard, a dozen bound books, a lump of damp cotton wool, sheets of blank paper, as well as a "patient" who is ready to help you in this work.

Guided by fig. 127, try to implement the three styling shown on it:

a) Lateral view of the eye sockets (with the position of the wounded lying on his side). Lay the subject on the side. Under the head, so that it is located without skewing (the sagittal plane of the skull should take a horizontal position), put a pack of books, and a cassette on it. Check the correct position of the head from two points on the side of the crown ("nose - parallel to the cassette") and from the side of the subject's face ("eyebrow line - perpendicular to the cassette"). If a 13x18 cm cassette is taken, it must be shifted anteriorly, and reach its leading edge approximately to the projection of the tip of the nose, otherwise the orbit may be outside the limits of the film. The object for fixing the gaze can be found on the wall of the room - against the "patient".

b) Anterior image in the "kissing" position. Take an 18X24 cm cassette to cover the entire skull; the area of \u200b\u200bthe eye sockets will fit well into the 13X18 cm cassette oriented in the transverse direction. In order for the projection of the eye sockets to occupy the middle sections of the 13 X 18 cm film, the patient's chin must be placed at the very edge of the cassette (or even on the table at its edge). Do not forget to put a piece of clean paper under the patient's lips for hygiene reasons. Put a damp cotton wool under the patient's eye on the cassette - this will be an object for fixing the gaze. It should be placed approximately at the tip of the nose along the line dividing the palpebral fissure in half. In this case, the axis of the eye will approach the perpendicular to the cassette. The head should be in a strictly symmetrical position in relation to the film. It is more convenient to follow this from the side of the crown (and not from the side), so that your eyes are at the same level as the head of the subject. Sometimes there is a need to take the patient's hair aside: they interfere with observing his eye. It is better to place the patient's hands on the sides of the cassette, palms down. Resting on the hands will somewhat reduce the pressure on the nose and chin and increase the degree of immobility of the subject's head.

c) Semi-axial image... Sit the "wounded" man on a chair at the end of the table. On the edge, put a stack of books on the table so high that the "wounded" man could freely lower his chin on it and at the same time the head would be tilted forward by 25-30 °. Place the cassette under your chin so that its middle part is located on the projection of the eyeballs. Moving to the other end of the table, see if there is a deviation of the head to the side. If necessary, make an amendment. Your finger, or an object on the wall behind you, is equally convenient for fixing the "wounded" gaze. Remember that the distance of the eye from the film in this picture should be about 12 cm. Therefore, if a child is being examined, it is useful to put a box of matches under his chin on a cassette. If, on the contrary, the facial skull of the wounded is lengthened, then it is advantageous to tilt the head anteriorly by more than 30 ° (until the eyes come to the required distance to the film). If the patient cannot look directly from under the forehead with such a strong tilt, then it is better to put the chin on a support, and raise the cassette higher using an additional insert.

Exercise 2. Centering the tube for skeletal radiography of the eye sockets in different projections and developing the optimal mode of images.

At this stage, the work should be transferred to the X-ray room; it must be done by an X-ray technician... Repeat the exercises you have already done and see how the technician centers the tube with each of them. Check for correct alignment as described above. Now ask the X-ray technician to take and develop images in all three projections. Carefully review and rate these images using the following criteria. With proper placement and centering of the tube along the mid-plane of the skull, images in the anterior and semi-axial projections will be characterized by symmetry of the contours of the left and right halves. A good lateral shot is distinguished by almost complete coincidence of the shadows of the outer contours of the entrance to the orbit and the layering (rather than divergence) of the shadows of the frontal-main processes.

Using fig. 128, 129 and 130, learn to find the main X-ray anatomical landmarks in the eye socket area in such pictures... This part of the exercise should be performed on dry photographs, specially selected from old medical records, or using a training kit (if available). The images should be considered optimal if they show massive shadows, a thin bone pattern of the structure of the orbits, as well as the delicate contours of the eyelids or the anterior part of the eyeballs. Evaluate which of the images at your disposal can be considered good, which are satisfactory, and which are very bad.

Quite a common form of examination of diseases of the eyeball and orbits. Orbital X-rays are usually given when the doctor is unable to examine the eye with an ophthalmoscope. This kind of shot shows bone structures around the eye and eyebrows (the so-called frontal and maxillary sinuses), the bridge of the nose and parts of the cheekbones. The procedure is often combined with CT or ultrasound.

In order not to irradiate the body during x-rays of the eye, the patient is put on a lead apron.

Orbital X-ray appointments

An X-ray of the eye is especially needed if the foreign body in the eye has metal particles, because the magnetic field of the MRI is able to attract and move them, disrupting the eye shell. Diseases for which an x-ray of the eyeball and nearby bone structures is prescribed:

bone fractures around the orbit;
maxillofacial injuries of other types;
foreign objects;
disturbances in the lacrimal glands,
diseases blood vessels and fatty tissue of the eye.

Preparing for X-ray

The preparatory stage for the procedure is the removal of all metal jewelry from the head and hair.

X-ray is a completely painless procedure, but sometimes it is not entirely comfortable due to the special position that the patient's head must occupy. As with other types of x-rays, it is important to get rid of all metal jewelry and removable dentures... There should also be no foreign elements on the hair. All strangers are removed from the room in which the radiography is performed, and the radiologist is placed behind a special glass window.

Features of the procedure

Usually the patient should sit on an X-ray table or in a special chair. It is important not to move until the doctor tells you to. X-rays of the eye often require a series of images, depending on the diagnosis. It can be performed in the following projections:

lateral;
anteroposterior;
chin-vertical;
bilateral;
semi-axial;
in the direction of the visual canal;
top.

During the procedure, the head should not rotate freely. The chin is pushed forward, the center of the instruments is set along the deepening of the upper lip. In the lateral position, the interpupillary space should be placed perpendicular to the instruments. When a foreign body is found, the specialist takes two X-ray images: when the patient looks up and down.

The duration of the procedure usually does not exceed 10-15 minutes, but it all depends on the patient's perseverance and efforts.

Decoding pictures

A thorough examination of the image is carried out by the attending physician, who identifies the abnormalities by comparing the image with a healthy eye.

Usually, a doctor is invited for decryption, and he is already looking at the images on the computer. It is important to see all asymmetric zones, because it is these areas that indicate the focus of the disease. X-rays of this kind usually require very careful work with the images, because cracks and fractures with craniofacial trauma are quite tiny. Parts of the shattered bone can even overlap. It is important to monitor changes in wall density (normally 1 mm or less), because thickening can mean cancer or another type of bone disease. The comparison is made primarily with a healthy eye. Usually, changes in the images indicate a number of diseases, which are described in the table.

CM - cantomeatal line connecting the lateral commissure of the eyelids and the external auditory opening; CRL - central X-ray),
and - nasal (frontal front-occipital) projection of Caldwell,
b - naso-chin styling,
in - Front semi-axial (chin) projection Waters,
r -basal (axial, submentortex) projection,
d - oblique front projection according to Rhese

X-ray diagnostics of foreign bodies of the eye is often carried out using special prostheses with marks or contact glasses, in case of severe damage to the eye and the impossibility of using traditional methods, you should use the marking method according to Vodovozov - a small piece of paper is applied to the limb or cornea with a grain of contrast agent glued to it (bismuth , barium, etc.).

X-ray diagnostics of foreign bodies of the eye consists of two stages:

the first is to establish the very fact of the presence of a foreign body in the eye or orbit, that is, to determine it. X-ray of the skull in the front direct projection allows you to get a general idea of \u200b\u200bthe state of the bones of the vault, cranial sutures, pyramids temporal bone... The interpretation of the state of the orbit is difficult due to the layering of the bones of the skull base on its upper parts. However, the entrance to the orbit and its bottom are clearly visible.
the second stage, if a foreign body is detected, the establishment of its exact location in the eye, i.e. its localization.

Patient laying

Basic (standard) styling for this study are

nasolabial (anterior fronto-occipital) Caldwell projection. Lying on my stomachthe patient touches the cassette with the tip of the nose and forehead. Angle between X-ray directionray and cantomeatal line, which is 15-23 °, leads away the shadow of the temporal bonedownward from the orbit image.
naso-chin styling. The patient lying on his stomach touches the cassette tightly whenwrinkled nose and chin.
anterior semi-axial (chin) projection Waters. Patient lying on his stomachent touches the cassette only with the chin, the tip of the nose is located 0.5-1.5 cm above the cash registerthat. The angle between the cantomeatal line and the central x-ray is37-45 °.
basal (axial, submentortex) projection... Under the shoulders of the one on your backthe patient is placed with a roller so that the head thrown back touches thesets with the parietal, and the infraorbitomeatal line (MI) was parallel to the cassette and perpendicularis cular to the central x-ray.
oblique anterior projection according to Rhese. The patient's head is laid on his stomachso that the browbone, zygomatic bone and the tip of the nose are pressed against the cassette. Centerthe ray is carried out on the opposite parietal tubercle, alternate images of boththe eye sockets are strictly symmetrical.

In addition to the indicated basic (standard) styling, three additional (special) ones are used:

styling "on the nose",
laying on "frontal tubercles",
oblique anterior (posterior) projection according to Rhese

Nasal (anterior fronto-occipital) laying according to Caldwell (1918) allows you to study the contours of the entrance to the orbit, the fossa of the lacrimal sac (1),medial (2) and lateral (3) walls of the orbit, ethmoidal labyrinth (7), frontal sinus (8). Infraorbital margin score (4) fordifficult due to the superposition of the shadow of the lower wall of the eye socket, in front ofthe third of which is located below the edge, the middle one is at its level,the back is higher. Such important anatomistsical formations, such as the upper and lower orbital fissures, wings of thenovoid bone (6 - large wing sphenoid bone) in this picture are covered by the pyramids of the temporal bones (9).

A snapshot taken with naso-chin styling with a tightly pressed nose, is an overview of the eye sockets in a direct projection, allowing you to compare the shape and size of the margo orbitalis. In addition, this arrangement is the main one in the study of the frontal, maxillary sinuses and ethmoid labyrinth. Finally, with naso-chin placement, the bones of the facial skeleton are clearly visible.

Anterior semi-axial (chin) projection by Waters and Waldron (1915) is indispensable in assessing the condition of the anterior parts of the medial wall, roof and bottom of the orbit, zygomatic bones, lesser wing of the sphenoid bone, infraorbital foramen, as well as maxillary sinuses and ethmoid labyrinth.

Due to the abduction of the shadow of the temporal bone pyramid downward, the laying provides a clear visualization of the medial (1), lower (2) and upper (3) walls of the orbits, the infraorbital edge (4) and the canal of the same name (5), the frontal-zygomatic suture (6), the zygomatic arch (7), a lesser wing of the sphenoid bone (8), as well as frontal (9), maxillary sinuses (10) and ethmoid labyrinth (11). 12 - unnamed line (linea innominata); 13 - ethmoid plate of the ethmoid bone; 14 - cockscomb

Due to the clear image of the superior orbital wall, as well as the anterior and middle third of the inferior orbital wall, the projection is useful for visualizing vertically displaced fragments of the roof and bottom, including the diagnosis of their "explosive" and depressed fractures.

When interpreting the image, it should be remembered that due to the peculiarities of the placement, the image of the bottom of the orbit is 10 mm below the contour of the infraorbital margin. Thus, a full analysis of the condition of the lower wall of the orbit involves the use of chin and nasolabial styling.

Basal (axial, parietal, submentortex) projection according to Schuller (1905) and Bowen (1914) allows visualizing the lateral wall of the orbit and maxillary sinus along its entire length, the nasopharynx, the pterygoid processes of the sphenoid bone, the pterygo-palatine fossa, the sphenoid sinus and the ethmoid labyrinth. At the same time, the medial half of the orbits is covered by the image of the dentition of the upper jaw. Due to the need to overextend the neck, stacking is not applicable if damage is suspected cervical spine.

Lay on the nose (anterior sagittal projection) is intended to assess the condition of the wings of the sphenoid bone and the superior orbital fissures. Since the analysis of the images of the superior orbital fissures obtained when laying on the nose is significantly complicated due to the variability of its structure, when evaluating the images, one should first of all pay attention to the symmetry of their shape and size. Mild interorbital asymmetry is a variant of the norm, which cannot be said about the pronounced (2 mm or more) differences.

Basic styling used for diagnostics of orbitalfractures
	Rendered structure	Pathological changes
Chin	Front two thirds of the bottom orbital walls, zygomatic arch	Fractures of the upper and lower walls with vertical displacement of fragments
Chin	Maxillary sinus	Sinusitis, hemosinus
Nasolabial	Frontal sinus, ethmoid labyrinth	Hemosinus, mucocele, sinus wall fracture
	Unnamed line	Fracture of the medial and lateral walls of the orbit
	Sphenoid bone	Fracture lateral wall
	Back third of the bottom wall	"Explosive" fracture
	The upper wall of the orbit	Upper wall fracture
	Turkish saddle	Pituitary gland diseases
Basal (submentortex)	Sphenoid sinus and ethmoid labyrinth
	Lateral wall of the orbit	Fracture of the lateral wall of the orbit
	Zygomatic arch	Fracture of the zygomatic arch
Oblique front by Rhese	Visual channel	Fracture of the canal walls

Laying on the "frontal tubercles" (in which a bandage 3-4 cm thick is placed under the tip of the nose, and the central beam is directed anteriorly from the external auditory canals) allows visualizing the lower orbital fissures.

To display the visual channels, sequential radiography of the right and left eye sockets is performed in oblique anterior (posterior) projections according to Rhese (1911). Normally, the vertical size of the visual aperture in the obtained image is 6 mm, horizontal - 5 mm, and the interorbital asymmetry of the size of the visual apertures in 96% of patients does not exceed 1 mm. Both an increase in the vertical diameter up to 6.5 mm and more, and a clear (over 1 mm) asymmetry of the visual apertures indicate pathology.

In addition to the visual opening, the image shows the roots of the lesser wing of the sphenoid bone and the upper sections of the ethmoid labyrinth. Sometimes a pneumatized anterior inclined process can be mistaken for the optic opening. To avoid misinterpretation of the radiograph, it should be remembered that the optic opening is located at the lateral edge of the wedge-shaped eminence (jugum sphenoidale).

With the introduction of CT into everyday practice, Rhese styling is rarely used. The interpretation of radiographs of orbital fractures differs significantly from that of fractures of any other localization. Certain difficulties are created by a complex image of the facial skeleton on a radiograph, about sectional distortion and the effect of layering various bone formations.

To reduce the fields of irradiation and obtain more contrasting radiographs, which show quite clearly images of even small foreign bodies, radiography is performed with a narrow aperture (10-15 mm), directing the central beam to the examined orbit.

In cases of injury to both eyes (after an explosion or a gunshot wound), complete images of each eye socket should be taken separately. When examining each patient, ordinary, bone, radiographs must be supplemented with clear skeletal images of the anterior segment of the eye, since small and low-contrast fragments located in the anterior part of the eye can often be visible only in these images.

Skeletal examination should be performed even in cases where the shadow of a foreign body is determined on ordinary images, since other than it, other less radiopaque fragments may appear in the eye.

Standard x-ray examination the orbital and paraorbital structures include Caldwell nasolabial (anterior fronto-occipital) fold, naso-chin fold, Waters anterior semi-axial (chin) fold, lateral and parietal (submento-vertex) fold.

In most cases, for the localization of a foreign body, the Comberg-Baltin technique is used, in which an indicator prosthesis is placed on the eye with lead points applied to it on the meridians 3-9 and 6-12.

In cases where a foreign body is poorly visible or not at all visible in the direct projection image, but it is detected on the radiographs in axial and lateral projections, it should be localized according to the Abalikhin-Pivovarov method.

Additional ways of indicating the dial

In cases where extensive penetrating wounds of the eye or rough scars do not allow the prosthesis to be placed on the eyeball, the limb can be marked with dots of bismuth slurry (basic bismuth nitrate with vaseline oil in equal parts) or with AM Vodovozov's dots, applying them along the meridians indicated above. This procedure is performed by the ophthalmologist just before the shooting, when the patient is already on the table. Previously, the eyelids are pulled back with the help of adhesive plaster strips or with special clips-blepharostats. In most cases, the point cannot be applied along the 12 o'clock meridian, since the upper limb, as a rule, remains covered by the corresponding eyelid. But even for three points, calculations can be made quite accurately. The calculation principle remains the same as when marking the limb with an indicator prosthesis.
If X-rays are taken after surgical treatmentwhen the conjunctiva is superimposed seams and they interfere with the application of a prosthesis to the eyeball, you can use a prosthesis with a cut segment. The cut part of the prosthesis falls on the protruding seams.
When shells fall out eye marking of the eyeball can be done with a Bowman probe. During frontal (face up) and lateral scans, the doctor touches the tip of the probe to the center of the cornea.
When calculating the frontal image, the measuring scheme is applied so that the anatomical axis of the scheme is aligned with the tip of the probe, and the horizontal meridian of the scheme would be parallel to the anatomical horizontal. On the lateral X-ray, the tip of the probe corresponds to the anterior pole of the eye. The side circuit is superimposed so that the front pole of the circuit is aligned with the tip of the probe, the bullet line of the circuit indicating the plane of the dial is parallel to the corresponding edge of the film. Further calculations are performed in the same way as when marking the limb with a prosthesis.
Thus, all three basic coordinates are determined, characterizing the location of the fragment in the eye.

Combination of primo and axial localization images

In practice, there are cases when a foreign body, due to low contrast, is not detected in the lateral image, but its shadow is visible on the direct and axial images. In such cases, it is possible to localize the fragments by combining images in the direct and axial projections performed with the Baltin prosthesis on the eye.

The meridian of the fragment location and its distance from the anatomical psi are determined from the direct image, and the distance from the limb plane is determined by the axial image.

Skeletal anterior ocular radiography techniques

The essence of the skeletal examination of the eye is to obtain an X-ray image of its anterior segment without the imposition of bone shadows on it, as a result of which it is possible to obtain shadows of very small and low-contrast fragments. Therefore, every patient with a suspicion of the presence of a foreign body, in addition to bone images of the orbit, must necessarily take skeletal radiographs of the anterior segment of the eye

according to Baltin's method and Polyak's modification

The technique is as follows

The patient's head is placed on the shooting table so that the sagittal plane of the skull is at an angle of 45 ° with respect to the table.
A 6x6 cm film, inserted into an appropriate size envelope made of opaque paper, is applied to the outer wall of the orbit and fixed with a cotton-gauze roller.
The tube is centered on the nose bridge.
The focal length is 60 cm.
The patient is asked at the time of shooting to open his eyes as wide as possible

If on a skeletal X-ray taken using this technique, the shadow of the fragment is not detected, and the clinical data indicate the possibility of a foreign body in the eye, it is necessary to conduct a study

according to Vogt's method

To take pictures, double films of 5.5x2.5 cm are used, rounded at one end (they are cut out according to a metal template). These films are wrapped first in black, then in wax paper to protect them from light and tears. Double films must be in order to distinguish random artifacts from the shadows of the fragments - the latter will be visible on both films in identical places.
Survey nonskeletal images according to Vogt are made in 2 mutually perpendicular projections: lateral and axial.
The distance from the focus of the tube to the film for both shots is 50 cm.

To take a picture in the lateral projection, the patient is placed on the side of the healthy (!) Eye, having previously installed its 0.5% alkaine solution into the conjunctival sac. The film is introduced with a rounded end into the conjunctival cavity and pushed as far as possible into the depth of the orbit between its inner wall and the eyeball, while the film is slightly bent, modeling along the curvature of the eyeball.

The x-ray beam is centered on the anterior part of the eye, directing it perpendicular to the film. At the time of shooting (this applies to pictures in both projections), the position of the eye should be such that its visual axis is parallel to the longitudinal edges of the film, and the plane of the limb is perpendicular to the latter.

After taking the picture, you must immediately mark top corner the end of the film, which was not introduced into the conjunctival sac, in order to subsequently know for sure that this particular corner corresponds to the upper part of the eyeball. The easiest way to make this mark is by folding the film.

Axial view performed in the sitting position of the patient, with the head slightly thrown back, or in the supine position, with the chin brought to the load. In any case, the position of the head should be such that the brow ridges do not cover the anterior segment of the eye. The film with a rounded end, slightly simulating it along the curvature of the eye, is introduced into the lower conjunctival fornix and, as far as possible, is pushed into the orbit between its lower wall and the eyeball. After taking the picture, remove the film from the conjunctival cavity and bend its corner in the nasal half in order to further distinguish the nasal half of the picture from the temporal.

After identifying the shadow of a foreign body on boneless images, the fragment is localized.

Localization images are performed in lateral and axial projections in the same way as survey images according to the Vogt technique, but with the obligatory marking of the limbus. One of the methods of marking is to apply a small drop (1-1.5 mm in diameter) of bismuth gruel to the limb along the meridian for 6 hours using a muscle hook or a glass rod. After performing localization images, always first carefully remove the bismuth gruel from the limbus with a wet cotton swab, and only then remove the film from the conjunctival sac, marking its corresponding corners.

When performing both survey and localization images using the skeletal technique, the doctor only inserts the film into the conjunctival sac, and holds it during the entire study time by the patient himself using any clamp, between the branches of which you can clamp the non-rounded end of the film. If a this study held for the child, the film is held by the person accompanying him.

On a correctly performed lateral skeletal localization image, the soft tissue profile tissues of both eyelids are visible and the shadow of the cornea is rounded between them. The contour of the bismuth point adjoins the contour of the cornea in its lower part, if it goes beyond the contour of the cornea, this means that at the time of shooting either the position of the eye was incorrect, or the bismuth point was not set strictly along the 6 o'clock meridian, but shifted towards 5 -and or 7 o'clock. In this case, the image needs to be redone.

In the axial image, the soft-tissue shadow of the anterior segment of the eye and the upper eyelid have the outlines of symmetrical semicircles. The bismuth point should be located within this shadow along the midline between the longitudinal edges of the film.

Localization calculations

The method for calculating the localization of foreign bodies from skeletal images was proposed by E.S.Vainshtein. They are based on the calculation principle applied by A.A. Abalikhin and V.P. Pivovarov.

Calculations for lateral and axial images are performed using the same measuring circuit, which is a special contour of the meridional section of the eyeball against the background of a grid of square divisions equal to 1 mm. The axial and limbal lines are highlighted in the diagram.

The state of the fragment from the plane of the limb and, at the same time, the distance from the horizontal axial plane (upward or downward) is determined from the radiograph in the lateral projection. To do this, the measuring circuit is applied to the image so that the intersection point of the corneal contour and the limbus line in the diagram would coincide with the shadow of the bismuth point in the image, and the image of the cornea in the diagram would fit into the corneal contour in the image.

After that, according to the divisions plotted on the diagram, the number of mm separating the fragment from the plane of the limb and from the horizontal axial plane is counted.

The axial image is used to determine the distance of the fragment from the vertical axial plane (to the nose or to the temple). To superimpose the measuring scheme on the axial image, it is rotated so that it corresponds to the section of the eyeball along the horizontal axial plane.

Then the diagram is superimposed on the image so that the longitudinal edges of the diagram and the image would be parallel to each other, and the point of intersection of the sagittal axis and the limb line on the diagram would coincide with the bismuth point in the image. After that, it is determined at what distance from the sagittal (vertical axial) plane of the eye the fragment is located.

The two values \u200b\u200bobtained - the distance of the fragment from the vertical and horizontal axial planes - determine its distance from the anatomical axis and meridian of occurrence, using either the schemes of A.A. Abalikhin, or the table and meridional scheme of E.S. Vainshtein.

Examination of the upper eyelid and external adhesion of the eyelids

To differentiate foreign bodies in the eyeball from debris projected onto the eye from the upper eyelid and external adhesions, isolated skeletal images of the upper eyelid and external adhesions should be taken.

For this, a double film, wrapped in dark and waxed paper or placed in a cassette for skeletal images, is inserted into the superior conjunctival fornix or inserted between the outer eyelid adhesion and the eyeball. The X-ray beam is directed perpendicular to the film.

In this case, the technical conditions of shooting should differ from those for taking a snapshot of the anterior segment of the eye along with the eyelids: voltage and exposure should be reduced, otherwise the soft tissues of the eyelids and adhesions, as well as low-contrast fragments in them will be "pierced" through.

Diagnosis of fragments in the border zone of the eye

The difficulty in diagnosing foreign bodies located in the so-called border zone of the eye lies in the fact that the size of the eyeball in different people vary over a wide range - from 21.3 to 31 mm. Thus, the width of the so-called border zone can be about 10 mm. Such fluctuations in the size of the eye, if not taken into account, can become a source of errors in the localization of fragments. It follows from this how important information about the individual dimensions of the injured eyeball is.
There is a complex technique - X-ray ultrasound localization of foreign bodies. It consists in the fact that in addition to X-ray localization of foreign bodies, ultrasound biometry (UZB) of the injured eye is performed, i.e., the distance from the anterior pole of the eye to the posterior membranes is measured. Since the thickness of the posterior membranes, according to different authors, ranges from 0.5-0.8 to 1.7 mm, we recommend adding 1.0-1.5 mm to the UZB data to obtain the entire length of the anteroposterior axis of the eye.

In the case of a borderline location of a foreign body, having data on its distance from the plane of the limbus and the anatomical axis, as well as knowing the size of the eyeball, to resolve the issue of the intra- or extraocular location of the fragment, one can use the one compiled by V.A.Rogozhin. It contains information about the length of the radii of the frontal sections of the eye, remote from the plane of the limbus at any possible distance in spherical eyes of different diameters - from 20.0 to 28 mm. In other words, it contains numbers denoting the maximum possible distance of intraocular fragments from the anatomical axis at different distances from the limbus plane in eyes of different sizes.

The numbers in the first vertical row of the table indicate the possible distance of the fragments from the plane of the limb within the eye. The numbers in the first horizontal row indicate the diameters (sizes) of the eyes. At the intersection of vertical and horizontal rows, numbers are placed, meaning the maximum possible distance from the anatomical axis of an intraocular fragment located at a specific distance from the plane of the limbus in an eye of a certain size. If, as a result of X-ray localization, it is established that the distance of the fragment from the anatomical axis exceeds that in the corresponding column of the table, then the fragment is located outside the eye, if it does not exceed (equal or less than the number indicated in the table), then the fragment is intraocular.

For example, according to UZB, the diameter of the injured eye is 25 mm. According to X-ray localization, the fragment was removed from the limbus plane by 10.0 mm, and from the anatomical axis - by 12.0 mm. In the first vertical row of the table, we find the number 10.0, corresponding to the distance of the fragment from the plane of the limb, in the first horizontal row, we find the number 25, corresponding to the size of the eye. At the intersection of the horizontal and vertical rows, we find the number 12.49 - the maximum possible distance for an intraocular fragment from the anatomical axis at a distance of 10.0 mm from the limbus plane in an eye of a given size. In our example, the distance of the fragment from the anatomical axis is 12 0 mm. Consequently, the intraocular fragment is located in the membranes. If in our example the distance of the fragment from the anatomical axis were, say, 13.5 mm, then the fragment should already be considered extraocular.

Thus, the use of X-ray, UZB and the proposed table in the complex significantly increases the efficiency of diagnostics of foreign bodies located in the border zone of the eye, but does not completely solve this problem. The question of the intra- or extraocular location of the fragment in some cases remains unresolved, and then it is recommended for X-ray surgical examination in the operating room according to the technique developed by I. Ya. Shitova.

This technique, in addition to X-ray localization of foreign bodies and UZB, includes the production of posterior boneless X-ray of almost the entire eyeball. For X-ray surgical examination, a cassette for skeletal x-ray of the anterior part of the eye is used, in which the working part, made of aluminum, is lengthened to 7 cm.

In the absence of a special cassette, the film can be wrapped in opaque paper and placed in a sterile rubber fingertip.

Preliminarily, the coordinates of the occurrence of a foreign body are determined by the Comberg-Baltic or some other X-ray technique. Then, after preparation of the operating field and anesthesia, the conjunctiva is cut in the meridian of the foreign body near the limbus and the conjunctiva is deeply exfoliated. The success of the diagnosis largely depends on how carefully the sclera is freed from the adjacent soft tissues.

Then the corresponding rectus muscles are ligated and, if necessary, cut off. A thorough examination of the sclera is performed. In the meridian of the foreign body at the appropriate distance from the limbus plane, a place for the subsequent diascleral incision is marked with brilliant green, a small metal mark is sewn episclerally, which serves as a reference point during the operation.

A film is injected close to the sclera under the control of the eye, making sure that no soft tissues are pinched between it and the eyeball. The X-ray beam is directed perpendicular to the plane of the film through the entire eyeball. If in the path of the rays passing between the anode of the X-ray tube and the film there is a fragment that traps the rays, then its tint image will remain on the film. In these cases, we can confidently speak about the location of the fragment in the eye, since a foreign body located outside the eyeball will not give a shadow on the film.

An orbital X-ray is a type of diagnosis, the essence of which is the passage of a beam of X-rays through the area under investigation, as a result of which its strength decreases, which is ultimately displayed on film or some other information carrier.

Whatever the indication for this procedure, an X-ray of the eye should always be performed in several projections, since with this diagnostic method, a three-dimensional picture is reflected on a plane. This means that in order to see the exact location of the tissues, one image will not be enough.

The main purposes of orbit x-ray are: detection of diseases of the orbit, its injuries, as well as foreign objects.

With the help of an X-ray of the eye socket, the doctor can easily detect foreign objects in this area, although in some cases a combination of an X-ray of the eye socket with an ultrasound and CT scan may be necessary for a more thorough examination.

The main advantages of X-ray of the orbit include its relatively low price in comparison with other research methods and the ability to see fractures of any type on the image.

Despite the fact that this procedure is quite safe, it still has some contraindications. So, an X-ray of the eye socket is not recommended for pregnant women, and for children under 14 years old, it should be done only in case of urgent need.

Indications for the procedure

Most often, an X-ray of the orbit is required in the following cases:

with recent injuries or fractures in the eye area;
if there are degenerative eye diseases;
in the presence of fresh wounds in the area of \u200b\u200bthe eyeball;
upon detection of benign or malignant tumors of the orbit;
if there is an eye contusion;
if an inflammatory or infectious lesion of the eye is detected (especially if the specialist suspects that the cause of this inflammation is the presence of a foreign body in the eye);
when old wounds are found in a healthy eye;
when syphilis or tuberculosis of the orbit is detected;
with congenital malformations of the orbit.

Preparation for the procedure

Orbital X-ray does not require any special preparation from the patient. Immediately before the procedure, patients are advised to remove all metal objects near their face (earrings, chains, removable metal prostheses). This is necessary in order to obtain the highest quality image (metal objects have the ability to reflect X-rays).

Procedure progress

During the procedure, the patient should lie on a couch or sit in a chair and at the same time not move until the device stops taking pictures.

As a rule, an X-ray of the eye socket implies a whole series of images that are taken in different projections:

anteroposterior;
chin-vertical (it is needed so that specialists can clearly see the base of the skull);
stereoscopic;
semi-axial;
front oblique.

If the doctor has found an enlargement of the palpebral fissure from above in the patient, then an additional image of the upper part of the orbit may be prescribed.

In order to detect the presence of foreign bodies in the eye in a patient and determine their location, specialists can use contact diagnostic techniques, their essence lies in the use of special indicators that are placed in the affected eye immediately before the examination. The most popular is the Comberg-Baltin method. This research technique allows you to determine the location of a foreign body with an accuracy of one millimeter. The induction implant used during the procedure looks like a contact glass with four lead marks, which are necessary for further calculations.

The entire procedure, despite its apparent complexity, takes only a few minutes. An X-ray of the eye socket causes absolutely no discomfort or pain, so this procedure should not be feared.

Until the images are developed and examined, patients are advised not to leave the hospital. This usually takes 30-60 minutes.

Although the X-ray will be taken on a rather delicate area of \u200b\u200bthe body, you should not worry about it. The modern equipment available in our clinic makes it possible to obtain the most informative results without harming the body. Contact our specialists and you will receive the highest quality service at the most affordable price.