The choice of the method of radiographic study of the clinical case
Four months before the consultation, the dog has already noted the symptoms of gastritis and performed the appropriate symptomatic treatment.
On the day of consultation, the animal observed a violation of the general condition, subfibral body temperature (39. 2 ° C), as well as vomiting long before feeding, while the vomiting contained undigested parts of the feed. The pronounced diarrhea with feces of dark green with an unpleasant odor was noted.
During palpation of the abdomen, slight soreness and stress of the abdominal wall were revealed. The state of the mucous membranes corresponded to the physiological norm.
As a result of a general clinical study, slow motionless intestinal motility was established, which aroused suspicion of the presence of partial body obstruction (foreign body, parietal tumor, invagination) or paralysis (chronic impaired intestinal or infectious nature). The possibility of poisoning was excluded by conducting an anamnesis.
As an additional clinical study, an X-ray was primarily conducted.
X-ray was performed by anfas in profile (photo 1 and 2).
|Photo 1. X-ray picture without preparation. Side projection (abdominal cavity). White arrows are the contour of the stomach. Blue arrows – the contour of the loops of the intestine.||Photo 2. A viewing radiograph without preparation (direct projection). White arrow is the contour of the stomach. Blue arrows – the contour of the loops of the intestine.|
Digital Chest X-ray Of Dog, Smithfield Road Veterinary Hospital, PLLC, Knightdale, N.C.
The quality of the radiographic image
* Density: in the lumbar region of the spinal column, intervertebral spaces are visualized, but the picture of the vertebrae indicates an insufficient exposure. The density is correct. * Contrast: objects of the abdominal cavity are well visualized. The contrast is correct. * Cleanliness: the contours of bones and soft tissues are represented by clear boundaries. * Position: rotation is noted on two radiographs. In the picture in the lateral projection, the transverse processes of the lumbar vertebrae and half of the pelvis do not have complete mutual overlap. The direct projection shows that the spinal column does not divide the abdominal cavity into two identical parts: the wings of the iliac bones are asymmetric, the dorsal apophyses of the spinous processes are not located in the center of the vertebrae.
Description of the radiographic picture
* Lack of visualized anomalies localized outside the abdominal cavity. * Due to severe emaciation of the animal, contrasting of structures in the abdominal cavity on the radiograph is weakly expressed and causes difficulty in studying organs.
– Complete identification of the small intestine throughout its length is difficult. Most segments of the digestive tract of large diameter are dilatated due to flatulence (photo 1 and 2: arrows). A pronounced gas formation, visualized in the cranial part and a dilatated segment in the caudal part of the abdominal cavity on the left do not allow them to clearly differentiate them from the transverse or descending segments of the colon.
– The contour of the stomach is difficult to distinguish in two projections. In the cranial part (photo 1 and 2: arrows) there is a weak granule zone, similar in density with minerals.
– The liver displayed on two radiographs is difficult to study, and its boundaries are poorly visualized. On two radiographs, the well-displayed dilatation of many intestinal segments caused by flatulence is associated with zones, which are density similar to the mineral.
The interpretation of the presence of zones similar in density with the mineral indicates the peresistence of a foreign body such as sand resembling gravel 1. The digestive tract segments dilated by gas can be similar to the colon (corresponding size and content), or small intestines increased in size.
1 form of gravel. In the contents of the intestine displayed on the radiograph, substances are sometimes observed that in density resemble a picture of excrement (a mixture of X-ray contact seals of soft and bone tissues). This image is represented by a dry part of the contents of the digestive tract, accumulated in the thin section of the intestine, which is called the “gravel” – the main sign of obstruction.
It is impossible to prove the presence of Ileus at this stage of the study. In this case, it is necessary to conduct an radiographic study using a contrast medium that gives the marking of the intestinal loops.
1. The choice of the method
To identify the dilatation of the digestive tract segments resort to one of two methods of radiographic examination using a contrast matter: to study barium transit, or barium washing (Table 1).
|Washing by barium||Transit barium|
|Indications||Damage to the colon. Morphological examination of the lumen of the colon, when there is no possibility of obtaining biopsy material from damaged areas of the intestinal wall (spikelet). It is possible to carry out air insoug into the colon of double contrast.||Vomiting (lack of response to symptomatic treatment or associated with other signs). The study of the anatomical modifications of the lumen of the entire digestive tract, with the exception of the large intestine. It does not allow accurately evaluate the physiology of the digestive tract.|
|Contraindications||During anesthesia. A diaphragmatic hernia (in this case, it is impossible to introduce air into the colon).||The perforation of the digestive tract: Passage of barium in the peritoneal cavity can provoke granulomatous peritonitis. In this case, it is preferable to use iodized contrasting water-soluble substances.|
|Implementation||The animal should be subjected to anesthesia. With the help of a probe equipped with a spray can, a barium suspension at a concentration of 20% is prescribed at the rate of 22. 2 ml/kg. X-ray studies are carried out in direct and lateral projections. Then the barium can be eliminated, and the body is filled with air in the amount necessary to create double contrast.||The digestive tract should be cleaned: a hungry diet lasting 12 hours (minimum), the purpose of laxatives and/or flushing. Sedation (if necessary): – dog: acetylpromazine at a dose of 0. 1–3 mg, in accordance with the size of the animal;- Cat: 10 mg of ketamin. Barium suspension 30%at a dose of 15 ml/kg, introduced using a probe (it is preferable to use the probe orally due to the risk of violation of the swallowing act). Radiography in direct and lateral projections: – immediately after taking barium (T0);- in the dog: T0 + 15 min. 30 min. 1 hour, 2 hours, 3 hours and then until the moment when barium reaches the colon;- At the cat: T0 + 10, 20, 30 min. Then every hour, until the moment when barium reaches the colon.|
|The time of implementation||At least 30 minutes.||Several hours (much faster in a cat).|
|average cost||41 Euro (2007)||116 Euro (2007)|
The study of barium transit in the digestive tract is carried out by oral administration or sends through the gastric probe. This product gives positive contrasting, visualized on an X-ray, which is monitored as it moves in the digestive tract up to the colon. To conduct this study, it is necessary to lack the contents of an alimentary nature: within 24 hours, only water is given with one- or twice washing of the intestine. Barium sulfate is the most commonly used product for contrast radiography. An exception may be an assumption of perforation of the digestive tract (in this situation, an iodized water-soluble contrast agent is used).
The prescribed dose of barium sulfate, diluted in water up to 50%, varies: for cats and dogs of small sizes, it is 12-16 ml/kg and large dogs – 5–7 ml/kg.
The flushing was washing in the appointment of a contrast medium of rectally with subsequent radiography. This allows you to mark the colon, up to the transition to the blind. In this regard, it becomes clear that using the usual method of radiographic research, it is impossible to obtain objective information without such preparation.
This type of study is also necessary to assess the ability of the digestive tract to evacuate the contents in it: the duration of the hungry diet, in which a small amount of contents remains in the digestive tract, is 24 hours (during this time it is necessary to drink only water and carry out one or two washing inResearch day).
As a contrast medium, a suspension container of barium sulfate is used. It is introduced slowly at the rate of 10–20 ml/kg. It is difficult to evaluate the optimal amount of contrast product, but this is necessary to obtain radiographs of optimal quality, which allows you to detect a thickening of the colon walls.
In our case, the question of the differentiation of the segments of the colon from the gas dilated by gas loops is solved (photo 3, 4).
They consider the flushing priority because this is the fastest way of differential diagnosis, achieved by introducing a contrast medium into the colon (barium sulfate in a volume of 150 ml, diluted with water to a concentration of 50%).
The radiography of the abdominal cavity is performed in direct and lateral projections (photo 3 and 4).
|Photo 3. An X-ray picture of the abdominal cavity (lateral projection), with a contrast matter. Visua is lysis of the segments of the intestinal loops, excessively increased in the amount of gas (arrow).||Photo 4. X-ray image of the abdominal cavity (frontal projection) with a contrast agent. Image of segments of the digestive tract not labeled with barium sulfate (arrows).|
* Density: X-ray exposure is somewhat overexposed. The contrast agent is clearly visualized, but the image itself remains strongly negative. The increase in exposure was intended to enhance the radiopaque part of the image. * Contrast: good, because an increase in the density of the colon compared to the density of the surrounding soft tissues is visualized. * Cleanliness: the contours of bone tissue and radiopaque structures are clearly defined. * Position: correct, as a result of which there is a good mutual overlap of the transverse processes of the vertebrae and halves of the pelvis in the lateral projection. On a frontal view, the vertebral column divides the abdominal cavity into approximately equal parts.
Description of the radiographic picture The colon, thanks to the introduction of barium sulfate as a contrast agent, allows you to see it up to the caecum. Gas-dilated segments of the digestive tract, not labeled with barium, are also visualized, mainly in the caudoventral region (photos 3, 4, blue arrows).
These segments of the digestive tract, not labeled with barium, refer to loops of the small intestine that are excessively dilated with gas.
Interpretation The simultaneous presence of normal and enlarged small intestinal loops in diameter is indicative of mechanical ileus.
However, this study does not allow us to establish the true cause of its formation, which was the reason for the diagnostic laparotomy, due to which it was possible to detect damage in the form of necrosis of the intestinal wall, accompanied by a pronouncedly acute course of enteritis.
The dog died due to malignant postoperative hyperthermia.
The barium flushing method was able to detect and identify gas-dilated segments of the small intestine and identify the ileus.
On the other hand, it is a fairly fast, economical and reliable way to make a diagnosis. With the help of radiographs, it was possible to identify the ileus, but not its nature.
The study of barium transit (more frequently used and longer in time) could possibly solve the problem of etiotropic diagnosis of ileus due to the lack of contrast marking of the intestinal area in which the tumor is localized.
However, in our case, the aim of the study was to confirm or not ileus.
Laparotomy is considered to be preferable compared to echographic examination, which is difficult to perform due to excess gas in the intestinal loops and the accumulation of a large amount of contrast agent.
>The transit of barium is carried out with the help of a gastric tube or by oral administration of an X-ray positive contrast product, which moves through the digestive tract to the level of the large intestine (colon).
>Barium flushing is performed by rectal administration of a contrast agent.
>Barium sulfate is the most commonly used radiopaque contrast agent, except in cases where gastrointestinal perforation is suspected, where a water-soluble iodinated contrast agent is used.