X-ray in dogs and cats: when to do and how much does an X-ray?

X-ray of the dog

X-ray examination is one of the most frequently commissioned and performed tests in veterinary medicine.

It enables the visualization of tissues, organs, bones and foreign bodies such as e.g. swallowed objects, stones in the bladder, pellets, etc.

Very generally, it can be said that X-rays penetrate the tissues and show the internal structures of the patient, thanks to which doctors can diagnose many diseases, which would be extremely difficult (often even impossible) using other diagnostic techniques.

The overexposure itself evokes extremely different emotions in owners.

From complete indifference and treating it like any other examination, to fears and anxiety, is it really necessary and will not harm the animal.

In this article I would like to dispel doubts regarding both the x-ray examination itself and the x-ray analysis.

There is no discussion about the fact that this is an important study, often significantly shortening the diagnostic path, and thus accelerating the introduction of appropriate treatment.

But is it really necessary today - in the era of new, modern techniques and research methods - to subject the patient to X-ray radiation (which is harmful after all)??

What can be detected with its help?

Which is not useful for X-ray?

I will try to answer these and other questions in the following study. So I invite you to read!

• History of X-ray
• How X-Ray Is Produced?
  • Construction of the X-ray machine
  • Formation of the X-ray image
  • Artifacts
• Properties of X-ray radiation
• The effect of X-ray radiation on the body
• Radiation protection
• Preparing the patient for X-ray examination
  • Appropriate patient positioning for an X-ray
• Whether the animal needs sedation or general anesthesia for an X-ray?
• Interpretation of X-rays
• Types of X-rays
• What can be seen on the X-ray image?
  • Chest overview image
  • Abdominal overview image
  • Radiographic examination of the bones
  • X-ray examination of the head
  • Radiological examination of the spine
  • Radiological examination of the joint
  • X-rays using contrast
  • Contrast examination of the gastrointestinal tract
  • Contrast examination of the urinary system
  • Contrast tests within the spine
  • Myelography
  • Epidurography
  • Discography
• X-ray in dogs and cats - price
• Which is not good for an X-ray?

History of X-ray

History of X-ray

X-rays were discovered by Wilhelm Conrad Röntgen in 1895 quite by accident.

Already at that time, the scientist conducted research on cathode radiation.

An electromagnetic field was created between the anode and the cathode in a glass vacuum tube.

As soon as the electrons reached the anode, the glass around it began to glow green, while the interior turned purple.

The scientist conducted this research until on November 8, 1895, on the day he placed a plate covered with barium platinum cyanide next to the discharge lamp.

As soon as Roentgen released electrons from the cathode to the anode, the plate began to glow blue.

At first he thought the light was coming from inside the lamp, so he covered it with black paper, but the plate still glowed.

This could not be justified by any physical law known at the time.

The scientist therefore concluded that he was dealing with new radiation, and the fact that the plate glows despite being covered by paper, proves that the radiation is quite penetrating.

He did not know the properties of the new discovery yet, so he initially called it X-rays.

And because it came from where the electrons were braking at the anode, he called it braking radiation.

The X-ray system therefore began to carefully study the new type of rays by placing various objects between the lamp and the screen.

These were books, playing cards, metal and wooden objects, and even your own hand.

The exposure time was then tens of minutes, now it takes fractions of a second.

The researcher lost himself in researching the new radiation and quickly determined its basic properties.

After extensive experiments on his discovery, in 1896 he presented his research to a meeting of the Physical Medical Society, taking an x-ray of the hand of one of the professors.

However, the very discovery of X-rays would not be so important were it not for the fact that the scientist wanted to record pictures taken with X rays.

Due to the fact that a quarter of a century earlier, glass plates covered with photosensitive emulsion were used for the first time in photography to take pictures and record them, the scientist used them for his purposes.

And this is how radiography was created - that is, taking X-rays.

Initially, X-rays were made on such glass plates.

In 1901, the scientist was awarded the Nobel Prize in Physics for his discovery.

He donated the entire prize money to his University.

It is extremely important for all mankind that this remarkable man did not patent his invention, so that X-rays could be (and is!) available to everyone.

As a result, tremendous progress has been made in both medicine and veterinary medicine.

Unfortunately, at that time, people were not aware of the harmful effects of X-rays (in honor of the discoverer, the new radiation was called X-ray).

Reports began to appear fairly quickly that people who had been exposed to radiation had burns on their skin.

Scientists dealing with this phenomenon on a daily basis were also unaware of its impact.

And the mortality rate in researchers who dealt with radiation (for medical or research reasons) was really high.

At the beginning of the 20th century, a Memorial Book was even created for those who died as a result of X-ray research, including doctors and radiological technicians.

X-ray examinations in animals began to be used extremely quickly.

The first attempts to use x-rays in veterinary medicine took place in 1896 in Germany and Great Britain.

How X-Ray Is Produced?

How X-Ray Is Produced?

Construction of the X-ray machine

X-ray radiation is created when free electrons, moving at high speed, are suddenly inhibited on a material with a high atomic number.

This phenomenon occurs in the X-ray tube that is part of the X-ray machine.

The X-ray machine consists of:

• X-ray lamps.
• High voltage generator.
• Distribution table.

The X-ray tube is a glass bulb in which there is a vacuum and 2 metal electrodes (negatively charged cathode and positively charged anode) are embedded in the form of a tungsten spiral.

Both electrodes are connected to high voltage. The cathode is additionally connected to the low voltage circuit - the so-called. glow circuit.

As soon as the apparatus is connected to the mains, electricity begins to flow through the glow circuit.

The tungsten wire in the cathode glows and when it reaches the right temperature, it begins to send electrons (based on the phenomenon of thermo-emission).

The electrons gather around the cathode, creating an electron cloud.

When high voltage is applied to both electrodes, the anode begins to attract electrons which travel towards the anode, where they then suddenly slow down.

The higher the voltage, the faster the electrons move towards the anode.

This is what happens when a radiologist or doctor presses a button while a picture is taken.

This is the moment of exposure.

The place where the electrons hit the anode is called. real lamp campfire.

It is set at such an angle that the generated radiation runs in a certain direction, exiting through the so-called. lamp window. The smaller the real focus, the lower the lamp power.
X-rays always run in the form of a beam, and the one that runs exactly in the center of the beam is called. main radius or central radius.

At the time of taking the pictures, the veterinarian sets the lamp in such a way that the central beam is directed exactly in the center of the area or part of the animal's body that interests him the most.

The projection of the real focus onto the plane perpendicular to the axis of the X-ray beam coming from the lamp is called. optical focus.

The smaller the optical focus, the sharper the image becomes.

So we want the optical focus to be as small as possible.

However, with a large real (and thus optical) focus, the lamp power is reduced.

In each lamp, it is possible to choose a fire place and adapt it to the size of the animal and / or the structures that we want to x-ray.

These are all very important details that are taken into account if we want to get a good quality X-ray image.

Formation of the X-ray image

To understand how an X-ray image is formed, it is good to look at how X-rays behave as they pass through a body.

Radiation, meeting an object on its way, can be subject to the following phenomena:

1. Penetration - this happens when radiation passes through low-density tissues that contain air, such as e.g. lungs.
   In such a situation, the rays reach the X-ray film practically without any losses, neither the direction nor the energy of the radiation changes.
2. Absorption - this process takes place in tissues of greater thickness and density.
   For example, when passing through adipose tissue (with a certain specific density), radiation is absorbed.
   In this way, fewer rays reach the X-ray film than was the case with air.
   It is these differences in the absorption of radiation between individual tissues that are (among others) responsible for the final image visible on the X-ray.
   This gives a specific visual effect on the x-ray image.
3. Scattering - this phenomenon consists in changing the direction of radiation.
   It is not beneficial from the point of view of radiologists.
   Such radiation reaches the X-ray film, causing its blackening in completely random places, which is referred to as image opacity.
4. The phenomenon of vapor formation - a very rare phenomenon, occurring with hard radiation.

As X-rays pass through an object, it is attenuated to varying degrees.

This is due to the absorption and scattering of X-rays.

Such a secondary beam of radiation reaches the X-ray film, giving a specific image.

Where the radiation has reached the film, blackening is visible (called brightening), and where the radiation has not reached, the X-ray film remains bright (called shading).

This perverse nomenclature is of historical importance.

In the past, X-ray films were lit by rays reaching them (which was called luminosity), and where the radiation did not reach, the film remained gray (shading).

Therefore, a radiograph is nothing more than the sum of light and dark areas fixed on the X-ray film.

Okay, but how is it possible that radiation reacts differently, passing through tissues and organs??

It is mainly influenced by the chemical composition of tissues, the ratio of the elements they make up, as well as the thickness and density of individual tissues.

In terms of radiology, body tissues can be divided into 4 main groups:

1. Non-absorbing tissues or organs, which contain gas, and which penetrate the x-ray film unobstructedly, causing it to blacken:
   • lungs,
   • sinus,
   • gas in the intestines.
2. Fat - this group includes:
   • subcutaneous fatty tissue,
   • intermuscular adipose tissue,
   • retroperitoneal adipose tissue,
   • mesentery,
   • the sickle ligament in a cat.
3. Tissues and organs containing no gas:
   • muscle tissue,
   • skin,
   • blood and lymph vessels,
   • liver,
   • spleen,
   • kidneys,
   • any other parenchymal organs.
4. Tissues containing calcium and phosphorus:
   • bones,
   • teeth,
   • calcified cartilage-bone joints of the ribs,
   • pathological calcifications (e.g. in the course of Cushing's disease).

Soft tissues, body fluids (such as blood), and water are similar in density and therefore absorb X-rays to a similar degree.

In turn, bones, teeth, calcifications contain calcium, therefore they absorb X-rays to a greater extent.

And it is precisely these differences in the absorption of radiation from individual tissues that allow to obtain the appropriate contrast, thanks to which it is possible to radiologically assess the x-ray image.

Artifacts

In order for the X-ray image to be of good technical quality and to be interpretable, it should be - as far as possible - free from artifacts.

These are all undesirable shadows present in the photo, which do not reflect the actual changes, and arise as a result of a technical error, both at the time of the overexposure itself and after it - during processing and developing the photo.

Despite the fact that digital radiography has become more and more common, still - when taking X-rays and processing them - all sorts of inappropriate shadows may form.

In most cases, the artifacts do not prevent the image from being interpreted, but pose a serious risk of error.

In addition to purely "technical " artifacts, such as: low contrast of the photo, blackened or bright areas in the image, decrease in image sharpness, etc., an important group of image distortions are those resulting from poor patient preparation.

Elements such as a leash, muzzle, collar, fingers of the holder, wet hair may obscure important structures and prevent precise assessment of the radiograph.

Properties of X-ray radiation

Properties of X-ray radiation

X-ray radiation is a beam of electromagnetic waves that propagate in a vacuum at a speed of approx 300 thousand. km / s.

This radiation has a number of very interesting properties that are always taken into account in the process of taking pictures.

Due to the strong, harmful nature of x-rays, the aim should be to take the picture as accurately as possible, without the need to repeat.

Therefore, radiological doctors and technicians place great emphasis on the appropriate preparation of the patient for the X-ray examination, its optimal positioning and the selection of exposure parameters.

In this article, I will only mention some properties that are important for both the patient and the caregiver.

However, I will not delve into the technical details that should be taken into account when taking and interpreting x-rays.

So let's see what properties this powerful radiation has.

You cannot see, hear or feel X-rays

It does not create a direct impression of light in the human eye.

From the point of view of safety for animal and human health, it is not a desirable feature, as it significantly hinders protection against the harmful effects of X-rays.

And since we do not know that we are being exposed to radiation at the time of shooting, we have not developed any defensive reflexes.

It spreads out in a straightforward manner

The X-ray beam coming from the lamp runs divergently.

That is why the obtained image is always larger than the examined object.

This is a very important feature, because the further the object is from the receiving plane (i.e. the X-ray film cassette), the larger the image, i.e. the greater the distortion.

That is why the cassette or the receiving surface is positioned so that it adheres directly to the overexposed part of the body - then the magnification is small.

X-ray radiation decreases its intensity with the square of the distance

It sounds extremely wise, but for us - doctors - one of the important conclusions is that the best protection against radiation is distance.

The farther the lamps we stand, the safer we are.

In the case of dental appliances, this safe distance is considered to be the distance 2 m.

X-ray radiation has an outstanding ability to penetrate bodies

This feature depends primarily on the energy of X-rays, but also on the degree of absorption by the overexposed object.

The greater the energy, the more penetrating the radiation.

Hard radiation (over 100kV) has a greater penetrating ability

X-rays are weakened while passing through an object.

The degree of this weakening varies, and depends on the thickness, density, and atomic composition of the compounds that make up the body.

For example: X-rays through the air pass without any obstacles, in adipose tissue it is slightly weakened, which intensifies slightly when passing through water.

In bones, in turn, the weakening of radiation is so great that a small part of it reaches the X-ray membrane.

Metals completely absorb X-rays - they will not reach the film and will not cause its blackening.

The second important conclusion from this feature is the fact that the use of appropriate shields will protect us against radiation.

It causes ionization of atoms and chemical compounds, which is a negative phenomenon from a biological point of view.

It has a harmful biological effect, leading to the development of unfavorable changes

As you can see, X-rays are full of various properties, of which I have only mentioned some important from the point of view of the animal's guardian.

Reading this short description, it can be concluded that the radiation is dangerous to health.

And it really is.

People who come into contact with x-rays must be especially careful not to undergo radiation.

Let's see how radiation affects human and animal health.

The effect of X-ray radiation on the body

Undoubtedly, X-ray radiation gives us tangible benefits in the form of the possibility of obtaining an image.

However, it has serious consequences.

X-rays are harmful to tissues and organs of both animals and humans.

The greatest damage is caused by radiation mainly in metabolically active tissues.

These include: bone marrow, gonads, and thyroid.

These biological effects, induced by X-rays, may appear relatively early, but there are also some that do not become apparent until months or even years later.

The early somatic effects of X-rays are:

• changes in the blood - a decrease in the number of:
  • leukocytes,
  • erythrocytes,
  • platelets,
• changes in the digestive tract, damage to the stomach wall, intestines; the most common symptoms are:
  • diarrhea,
  • vomiting,
  • more frequent incidence of gastrointestinal infections,
• changes in the reproductive organs (decreased fertility),
• skin changes:
  • erythema,
  • hair loss,
  • inflammatory changes,
  • ulcers,
  • possible skin cancers,
• changes resulting from damage to the fetus.

Pregnant women should under no circumstances participate in an X-ray examination, as this may lead to irreversible changes in the fetus, such as disturbances in the formation of organs, leading to deformation or even death of the fetus. Your baby may develop cancer, mental retardation, and other serious effects from radiation in the postnatal period.

The late effects of x-rays include:

• leukemia,
• shortening the life time,
• cataract,
• malignant tumors,
• sterility,
• inhibition of growth and development.

In addition, various unpredictable genetic mutations can occur in the DNA of reproductive cells.

A second division of the effects of radiation on the body is generally accepted, according to which there is some correlation between the radiation dose and the biological effect.

Non-chastic (deterministic) effects

It is a group of biological effects in which their intensity is strictly dependent on the size of the radiation dose.

These effects are predictable and will not arise if the radiation dose is sufficiently low.

Among other things, you should:

• cataract,
• damage to the hematopoietic system,
• skin burns,
• radiation sickness,
• hair loss,
• thyroid disease.

These effects will occur in the case of x-ray diagnostics, because lower exposure doses are selected here.

However, due to the fact that many people still remember the catastrophic effects of the Chernobyl accident (and huge doses of radiation), any type of radiation is associated with exceptional harmfulness.

Stochastic effects

The second group of - already unpredictable - effects are the result of ionizing radiation, the dose level of which is unknown.

This kind of radiation causes different types of gene mutations, and hence - hereditary diseases and the formation of tumors.

It is not known how high the threshold doses are, and it is not known whether and to what extent the body's defense mechanisms will be able to repair DNA damage.

It is known, however, that the probability of their occurrence increases proportionally to the radiation dose (but not the degree of their intensity)!).

Among the stochastic effects, there are late somatic effects and genetic effects.

Therefore, one of the methods of radiation protection is to protect the body against radiation as if it had no defense mechanisms at all.

Specialists follow the principle here:

any dose may be harmful.

Due to such serious consequences of X-ray radiation, it is necessary to introduce rules and protocols that will minimize the harmful effects of radiation, and at the same time ensure the final effect in the form of a diagnostically useful X-ray image.

Radiation protection

Radiation protection

Radiation protection is based on the so-called ALARA (As Low As Reasonably Achievable) principle - "as low as it is realistically possible".

It says that radiation doses should be optimized at the lowest possible level in order to obtain a diagnostically useful image, while maintaining safety conditions.

Therefore, a radiological examination should be performed:

• only in justified cases,
• using appropriate materials, technologies and methods,
• using trained people,
• even pacifying the patient.

The 3 most important principles of radiation protection are:

1. The further the safer. Since the irradiance decreases with the square of the distance, the distance is the best protection.
2. The shorter the exposure time, the lower the radiation dose.
3. Use of covers:
   • fixed (walls, ceilings, doors); the most commonly used materials for the production of this type of covers are:
     • barite concrete,
     • lead glass,
     • lead rubber.
   • moving (screens).
   • personal (gowns, gloves, glasses, shields for the thyroid gland and gonads).

I deliberately described the adverse biological effects of X-rays and the possibilities of protection against it.

One of the main ways to protect the patient and caregiver from the harmful effects of radiation is to make the caregiver aware of the biological effects of radiation.

The aim of protection is therefore to reduce exposure to radiation, but at the same time to achieve a measurable effect in the form of an x-ray image.

The owner participating in the study should therefore be aware of the seriousness of the study.

Minors, pregnant women and those suffering from neoplastic diseases and thyroid gland are always excluded from the X-ray.

Each person taking part in the study should wear an apron, a shield for the thyroid gland and protective gloves, and be thoroughly instructed in the procedure beforehand.

No other people may stay in the X-ray room, apart from the owner and staff.

On the other hand, a veterinarian - in order to reduce exposure to x-ray radiation - should exhaust other, non-radiation diagnostic methods beforehand.

If the owner already has an X-ray taken before, it should be used.

The person ordering and / or performing the examination must always consider the risk of losing the patient's health and the benefits of using radiation.

Considering the influence of x-rays on the body, one must not forget about one of its most important applications, both in human and veterinary medicine.

After all, it should be remembered that radiation therapy is widely used in the treatment of various types of cancer.

It is these "harmful" effects of X-rays along with their properties (such as affinity for rapidly metabolizing tissues) that made it possible to use radiation in the treatment and saving lives.

Well, since we already know how an X-ray image is created, and we are also aware of the risks associated with ionizing radiation, now let's see how to prepare a patient for an X-ray examination.

Preparing the patient for X-ray examination

Preparation for X-ray examination

The veterinarian always strives to ensure that the X-ray image is of the best quality.

This means that it should have the highest possible diagnostic value with as few artifacts as possible.

To achieve this, the patient should be properly prepared.

The owner should ensure that the pet is in the (planned!) the x-rays were on an empty stomach, because food in the stomach or intestinal contents make the examination much more difficult.

Before x-rays, it is advisable to administer substances that eliminate gases from the gastrointestinal tract.

Sometimes, especially when assessing the abdominal cavity, it is necessary to do an enema first.

To minimize distortions in the photo, remove any objects from the overexposed area.

So we remove the collar, earring, muzzle (in the case of head photos), harness, leash, etc.

Any visible foreign matter in the hair coat should be removed beforehand.

It often happens that by mistake "diagnosing " various, strange objects in the abdominal cavity or chest just because they were stuck in the matted hair in the examined area.

If you do not want to x-ray your pet several times (completely unnecessarily), you should carefully check if there are any accidental objects in the fur.

You should also avoid taking x-rays if the hair is wet - this may cause artifacts that make it difficult to interpret the image.

Sometimes it is necessary to take a photo of the limb that has previously been banded or stiffened - this makes the interpretation of the image much more difficult, therefore you should not take x-rays through a plaster or other stiffening.

Also preparations containing iodine (applied to the skin) or contamination with a contrast agent may contribute to a distorted image and make the photo unreadable.

Appropriate patient positioning for an X-ray

Personnel preparing the patient must pay particular attention to the way the patient is positioned.

It's not that we like to pull our paws or bend a poor guy in various ways.

X-rays cannot be taken accidentally.

The position of the patient's body, its position in relation to the cassette, distance from the X-ray tube, sometimes even the breathing phase - all this is of great importance if we want to visualize changes, often very small.

The more precisely we position the patient, the greater the chance of getting a good quality photo.

In order to get as much information as possible about the condition of your dog or cat, it needs to be put in the right position.

In what?

It depends on which area or part of the body we want to examine, but it is never a random choice.

Each type of image has specific items assigned to it, the application of which maximizes the chance of obtaining the appropriate image.

So, for example:

if you want a picture of your dog's neck and chest because you suspect it may have collapsed, it should be placed on its side.

There are three basic poses:

1. Lateral - the patient is lying on the left or right side. In short, it is said to be a left / right side view.
2. Sagittal - the patient is lying on the stomach (this is a dorso-abdominal image) or on the back (this is a dorso-dorsal projection).
3. Oblique.

To obtain a correct image, it is important to meet the following conditions:

• appropriate distance between the lamp and the X-ray film,
• the central radius should be directed perpendicularly to the tested plane (and preferably in its center),
• the part of the body to be tested should be as close to the cassette as possible and preferably parallel to it,
• the patient should not move when the photo is taken (of course, sometimes it is impossible to get the photo completely still, e.g. dog is panting intensely).

As you can see, there are many guidelines for proper x-rays.

It is mainly the doctor or technician who is responsible for correctly positioning the patient, selecting exposure parameters and setting the lamp.

The animal handler should strictly follow the instructions given by the staff.

And employees, in turn, should be precise in what they say.

Now let me tell you an anecdote that I witnessed:

I have had a chest X-ray taken on a dog with cancer.

The technician who prepared the patient for the X-ray instructed the owner that if she said "already " she should hide.

He used exactly that term, and it was his mistake.

Should say:

after hearing the word "already" please go out the door.

The assistant prepared the patient, set the parameters of the lamp, its height, put a marker on the cassette and said "already ".

Fortunately, he looked around the room before pressing the button

…

the head of the frightened caretaker of the animal was sticking out from under the table on which the patient was lying

…

She followed the words of the technician - she hid as best she could.

A little funny, a little scary.

But as you can see, understatements can be the source of a lot of trouble.

We also need to remember this.

Therefore, do not be surprised that the staff will inform you quickly, briefly and in soldiers' words what to do and how to behave.

Also, do not treat certain equipment that is in the X-ray room as torture tools.

The so-called fittings (pillows, wedges, rollers and other stabilizers) are to help in the correct positioning of the patient, and to immobilize him, strips of material, lines, bandage tapes, even a wide adhesive tape are used.

Nobody will hurt the animal with these items.

They are only used temporarily for the purpose of restraining and correct positioning of the patient.

Whether the animal needs sedation or general anesthesia for an X-ray?

Yes, many times premedication is necessary, and sometimes even general anesthesia.

Remember that our dog or cat that is to be x-rayed is most often scared - the animal does not understand why it is put on the table, stretched, and its limbs or head are set at different angles.

For him it is incomprehensible and terrible.

No wonder that patients often defend themselves against this type of manipulation, often becoming even aggressive.

This can be dangerous for the patient, owner and staff alike.

Therefore, for the pharmacological sedation of the animal, sedation may be required.

Sometimes, however, the poor general condition of the patient precludes the use of this type of medication.

Certain types of x-ray examination even require sedation and muscle relaxation.

This is the case with x-rays in which the patient's position is unnatural or requires adequate muscle relaxation in order to obtain the most diagnostic image.

This is what happens with some dog's head projections, as well as for x-rays and assessment of the hip joints.

Often, pet keepers object to sedation.

However, some photos just require it.

In the case of more invasive tests, such as. myelography, general anesthesia is necessary.

However, in many cases it is possible to take a photo without having to give "stupid Johnny ".

If the pet is calm, it can be placed on the table, and the necessary position does not require an unnatural position - the animal often withstands no problems for several dozen seconds.

Pharmacological sedation of the patient is not always necessary and it depends on two basic factors:

• temperament of the patient,
• type of X-ray.

Well, let's go back to our photo.

The patient is on the receiving surface (most often on an X-ray cassette or a special table top), the lamp is turned on (moment of exposure) and

…

so much.

That's all.

The X-ray image is taken, now it's time to develop and process it.

Until recently, an employee was responsible for developing such an image, nowadays standard radiography is increasingly being replaced by digital radiography.

This is a great help because all we have to do is insert the cassette into the digital scanner and the machine will show us the picture on the monitor.

You may only need to slightly "polish " the image by marking the sides, contrasting, reducing or increasing etc.

Interpretation of X-rays

X-ray interpretation

X-ray pictures are interpreted by a veterinarian (preferably a radiologist).

It consists in reading an X-ray image and compiling an initial list of differential diagnoses.

It then describes the apparent changes and relates them to the results of the clinical trial and other studies.

A diagnosis is made on the basis of all available information and an x-ray examination.

It also happens that the radiograph does not provide specific information that can explain the current clinical condition of the patient.

This is for the following reasons:

1. The x-ray image is of poor technical quality. Then, most often, a repeat photo is ordered.
2. Incorrect projection and / or patient positioning was selected, as a result of which important - from the diagnostic point of view - structures were not visible. In such a situation, the optimal position is selected and the x-ray is repeated.
3. The patient was not well prepared for the study (e.g. present content in the digestive tract). X-rays are usually postponed - the pet should return the next day on an empty stomach.
4. The animal struggled during the photo, it moved and therefore the X-ray image is falsified. If the patient's general condition allows, sedatives are given and the x-ray is repeated.
5. It is impossible to make a diagnosis of the particular condition that the patient suffers from by x-ray. If the picture is taken correctly and the radiologist does not see any changes that justify the patient's condition, look further. Most often then other additional tests are ordered.

Types of X-rays

There are different types of radiographs depending on what specific information we are looking for.

As I mentioned, nothing can be accidental in radiology and if the decision was made to take an X-ray, it should be done in such a way that with the least number of exposure to radiation, you get as much valuable data as possible.

Therefore, there are predetermined rules, projections and types of photos that apply in different cases.

And so we can distinguish, among others:

Typical photos

These are radiographs, the execution of which is precisely defined by regulations in such a way that they do not deviate from the established standards.

Thus, the following are predetermined in advance:

• patient positioning,
• location of the test area in relation to the cassette,
• inclination of the central beam in relation to the cassette (oblique images are also made),
• the distance of the lamp from the patient,
• method of immobilization,
• exposure conditions
• and other.

Overview photos

Performed to obtain an overview of an organ or body part.

Therefore, the most common are examinations of the chest or abdominal cavity.

Targeted photos

Here the beam of rays is directed to a specific area, e.g. on the pond.

Contact photos

They are performed by bringing the lamp directly closer to the skin surface.

This may be the case, for example. examined kneecap or breastbone.

Contrasting photos

They are performed with the use of a contrast agent.

What can be seen on the X-ray image?

What can be seen on the x-ray?

X-ray is widely used in veterinary medicine.

Thanks to it, it is possible, inter alia, to demonstrate:

• foreign bodies in the stomach or intestines,
• stones in the bladder,
• bone fractures.

Assessment of the shape, contours and location of organs allows you to find the cause of health problems many times.

X-rays can visualize tumors in the chest cavity or abdominal cavity.

They can also detect pregnancy and help the doctor estimate the number of puppies.

However, these are just some examples of the enormously rich potential of X-ray.

Depending on the type, location and projection of the x-ray, different organs are assessed by a doctor.

It is he who, on the basis of the previously conducted clinical examination, as well as additional examinations, decides whether an X-ray is necessary and determines the area of ​​interest and the required projection.

There are some predetermined rules that should be followed when taking x-rays.

Without going into details on a correctly made radiograph, a veterinarian looks for various types of changes that may be visible in the tissues, and which will allow him to confirm the initial diagnosis, and sometimes even to make a diagnosis.

These changes may concern the size, shape and structure of a given organ, the number of organs, their location, shading, and even function (the latter feature is assessed indirectly in a contrast test).

Each of these features is then subjected to a detailed assessment.

So let's take a look at what exactly the doctor can see on this mysterious X-ray, what are the indications for its taking, in what positions the animal should be positioned for particular projections and what disturbances are most often detected when interpreting x-rays.

Chest overview image

Indications for the study

A chest radiograph is warranted in the following situations:

• If the doctor suspects that the disease process (acute or chronic) is taking place in the upper or lower respiratory tract.
• If you already have a respiratory or circulatory disease. This study is designed to monitor the development of the disease as well as to evaluate the effectiveness of treatment.
• If you have a cancerous tumor (anywhere in the body) and you need to exclude (or confirm) metastasis in your lungs.
• If you have generalized enlargement of superficial lymph nodes (this is how your doctor assesses whether the lymph nodes in the chest cavity have also been enlarged).
• If your doctor suspects a disease of the trachea or esophagus, e.g. a collapse of the trachea, a giant esophagus, shading a foreign body in the trachea or esophagus.
• In animals with chest trauma. Always after an accident (traffic accident, fall from a height, being bitten by another animal, etc.) a chest X-ray should be performed. The organs within it (eg. pneumothorax, pulmonary hemorrhage, pulmonary edema, diaphragmatic hernia and many others).

Patient positioning

Chest x-ray examination most often it is performed in 2 projections:

on the right or left side of the animal and on the belly (or on the back).

In oncology, in order to exclude neoplastic metastases, it is best to make chest X-rays in all three projections.

This is important and you should not be satisfied with just one x-ray as it happens very often that changes visible in one view are not visible in the other.

Only the view obtained from different sides can give an overview of what is happening throughout the entire chest.

Unfortunately, it still happens that the doctor, assessing e.g. the right-side photo sees no changes, and - seemingly reassured - withdraws from taking the others.

It is often the owner's decision, who for various reasons refuses to perform further radiographs.

Right-sided projection

Standard picture taken.

The patient is lying on his right side, in such a position that the chest is on the receiving surface and the forelimbs are extended far towards the dog's nose.

In this way, we reveal important structures in the chest, which - if not stretched sufficiently - could be obscured by the front paws.

Dorso-ventral projection

The patient is lying on his stomach, the chest is on the cassette.

Left-sided projection

Often used for lung assessment and for the diagnosis of tumor metastasis

Abdominal-dorsal projection

When the patient is lying on his back.

It is used to assess lung tissue, but it is not often used (in the case of respiratory problems, this position may increase breathlessness).

Projection using a horizontal beam of rays in a standing patient

It is a projection recommended primarily for animals with dyspnoea, where lying on their side may significantly aggravate respiratory failure.

Often used to assess the presence of fluid in the pleural cavity.

Assessment of the radiograph

When assessing a photo, a veterinarian first assesses its technical quality.

He must pay attention to whether the individual details in the x-ray are clear enough to be assessed.

The technical quality of the X-ray image is influenced by the degree of its darkness, contrast and sharpness.

Currently, thanks to the introduction of digital X-ray images, the possibility of processing the image so that it has a high diagnostic value has significantly improved.

If the X-ray is technically well made and all necessary details are well captured, you can start analyzing individual chest structures, such as:

• chest wall,
• diaphragm,
• pleura and pleural cavity,
• mediastinum,
• trachea,
• lungs,
• heart,
• large blood vessels.

Possible changes that can be seen on the chest X-ray

A chest X-ray may show the following changes:

• Increase or decrease in the transparency of lung tissue.
  Any abnormalities in shading the lungs should be carefully analyzed.
  In this way, it is possible to recognize such clinical conditions as:
  • pneumonia,
  • cysts,
  • calcifications within the lung tissue,
  • emphysema blisters,
  • pulmonary oedema,
  • I will not give up,
  • pulmonary hemorrhage,
  • tumors (primary or metastatic) in the lungs.
• The presence of air in the pleural cavity (this is called. pneumothorax).
  This condition most often occurs as a result of an injury.
• Thickening of the pleura that may accompany aging dogs, but also appear as a result of inflammation, cancer, or circulatory disturbances.
• Air in the mediastinum (pneumothorax).
  It arises, inter alia, as a result of:
  • esophageal damage,
  • tracheal damage,
  • bitten wounds,
  • stab wounds,
  • rupture of the lung or bronchus.
• Presence of fluid in the pleural cavity.
  Unfortunately, we cannot distinguish the type of fluid we are dealing with on the basis of the X-ray image.
  It could be:
  • exudative fluid (e.g. in circulatory failure, decreased level of total protein, in the course of uremia),
  • blood or lymph (most often after injuries, but also in the course of neoplastic diseases, lymphatic diseases, inflammatory granulomas, cardio-pulmonary helminthiasis and many others),
  • exudate (accompanying various inflammations, often in cats with infectious peritonitis),
  • pus (as a result of purulent pleurisy, rupture of a pleural abscess).
• Heart shape abnormalities i./ or large blood vessels.
  The X-ray shows if the shape of the heart has changed and which part of the heart is affected.
  The size, shape and position of the heart as well as blood vessels (aortic arch, aorta, caudal vein) are assessed.
  One of the most important calculations used in the radiological assessment of the heart is the so-called. VHS factor.
  It is the ratio of the sum of the length and width of the heart to the thoracic spine.
  For dogs, it should be 9.7 circles (+/- 0.5), and for cats, VHS = 7.5 (+/- 0.3).
  If this factor is increased, it indicates that the heart is enlarged.
  Of course, there are some differences in heart size among breeds that deviate slightly from the standard pattern.
  The veterinarian, when assessing the shape of the heart, also takes into account such exceptions
• Pulmonary vascular abnormalities.
  They are generally poorly visible, but if they widen, it may indicate congenital heart defects (e.g. patent ventricular opening or patent ductus arteriosus).
  On the other hand, a reduction in the diameter of blood vessels within the lungs may be a symptom of severe dehydration, hypovolemic shock or diseases associated with a reduction in blood volume.
• Tracheal changes (contaminating foreign bodies, tracheal rupture, narrowing, collapse of the trachea).
• Changes in the esophagus (shading foreign bodies, tumors, giant esophagus).
• Congenital or traumatic hernias.
  In the case of diaphragmatic hernia, a contrast test of the gastrointestinal tract is often performed, thanks to which it is possible to visualize the displaced organs from the abdominal cavity to the chest cavity.
• Air in the esophagus.
  Normally, the esophagus should not be visible on the X-ray.
  Occasionally, a small amount of gas enters the esophagus, e.g. as a result of severe dyspnea, emotional agitation or pharmacological relaxation.
• Enlarged lymph nodes (mediastinal, sternal, tracheobronchial).
  Under proper conditions, they should not be visible on the radiograph.
  When they are visible, it may indicate inflammation or cancer (e.g. lymphoma).
• Abnormalities of the thymus gland, which are visible on the radiograph only in young dogs.
  If it is seen in a dog older than 2 years, it indicates a disorder in this organ.
• Chest wall abnormalities such as.:
  • changes in the thoracic spine,
  • changes within the sternum:
    • break,
    • sprain,
    • degenerative changes,
    • developmental disorders.

Abdominal overview image

X-ray of the abdominal cavity

Indications for the study

Abdominal x-rays are relatively often performed for all types of symptoms related to the gastrointestinal tract.

They can be:

• unexplained weight loss that does not go away with standard treatment,
• lack of appetite,
• vomiting,
• diarrhea,
• soreness of the abdominal wall,
• injuries,
• enlargement of the abdominal wall,
• difficulty (or lack) in passing urine and stools,
• bloody stools,
• blood in urine,
• worsening general condition for unknown reasons,
• suspected intestinal obstruction or perforation.

Contraindications

• poor general condition of the animal (in case we want to use contrast test),
• overloading the digestive tract with food.

Patient positioning

Right side side projection is the primary projection

The patient's abdomen is placed on the receiving surface, the animal is stretched: the forelimbs are strongly stretched forward and the rear limbs backward.

This is very important, because in the event of improper positioning of the limbs and the patient "crouching", the internal organs are crowded in the abdominal cavity and it will be difficult to assess the organs.

In addition, the structures of the abdominal cavity may be obscured by the bones and muscles of the limbs, which further complicates the interpretation (in fact, it even disqualifies such a photo and it is necessary to re-X-ray).

Photo in the abdominal-dorsal projection

In this projection, the patient is lying on his back, the hind limbs are placed in the "frog" position, and the front limbs are stretched out towards the head.

The spine is adjacent to the cassette.

Assessment of the radiograph

The abdominal overview image allows the assessment of such structures as:

• kidneys, visible under the spine,
• line of the diaphragm, located in the head from the kidneys,
• liver under the costal arch,
• stomach over the liver,
• the lingual spleen is usually located at the bottom of the abdominal cavity, however - depending on the filling of the gastrointestinal tract - it may not be clearly visible,
• small intestines that fill almost the entire abdominal cavity,
• the cecum, as a rule, filled with gas,
• the large intestine, its posterior segment is often filled with fecal masses,
• bladder (its shape depends on the degree of urine filling),
• retroperitoneal space - here are the lymph nodes, vessels, nerves that under normal conditions should not be visible on the X-ray,
• the uterus in a bitch - between the bladder and the large intestine; it is rarely visible on x-rays, sometimes it can be seen in bitch in heat or in larger females (> 20 kg),
• male prostate just behind the bladder,
• abdominal wall,
• peritoneal cavity.

Possible changes, which are visible on the overview image of the abdominal cavity

The most common abnormalities in the analysis of abdominal radiographs are:

• Various types of hernias, such as.:
  • abdominal hernias,
  • inguinal hernia,
  • hiatal hernia,
  • scrotal hernia, etc.
• Fluid in the peritoneal cavity.
  The radiograph shows blurred image in the abdominal cavity; gas is often visible in the intestines.
  Similarly to the presence of fluid in the chest, we are not able to assess radiologically what type of fluid we are dealing with.
  To find out, it is necessary to take a sample of the test fluid.
  It could be:
  • Exudate - the accumulation of serous exudate in the peritoneal cavity is known as ascites.
    Its most common causes include infectious diseases (e.g. in the course of feline coronavirus peritonitis), peritonitis, neoplastic tumors.
  • The leakage is present in such states as:
    • liver disease,
    • congestive heart failure,
    • hypoproteinemia.
  • Blood - bleeding into the abdominal cavity can occur for various reasons, most often it is trauma, tumor rupture (e.g. in the course of spleen angiosarcoma).
  • Lymph - the causes of the passage of lymph into the abdominal cavity are similar to those of the lymphocytic cavity.
  • Urine - when the bladder ruptures
• Peritonitis, which may include, but are not limited to:
  • infectious agents (e.g. feline coronavirus peritonitis),
  • inflammation and / or cancer of the pancreas,
  • injuries or penetrating wounds to the abdominal wall,
  • postoperative complications,
  • perforation of any part of the gastrointestinal tract,
  • a rupture of an abdominal organ.
• A lump or tumors in the abdomen.
  The most common tumors in the abdomen are spleen tumors.
• The presence of free gas in the abdominal cavity.
  This is always an abnormality, except for a short period (usually around a week) after laparotomy.
  The reasons for the presence of air in the abdomen are penetrating wounds of the abdominal wall or rupture of an organ.
• Dilation and torsion of the stomach.
  A sharp dilation of the stomach is seen as an enlarged stomach, filled with gas or with chyme.
  If the stomach twists, the pylorus changes its position.
• Intestinal disease states such as obstruction, inflammation, intussusception, and displacement.
• Enlarged retroperitoneal lymph nodes.
• Shading foreign bodies in the stomach or intestines.
• Constipation (that is, long-term accumulation of fecal matter in the posterior gastrointestinal tract).
• Megacolon (significant widening of the colon with residual fecal matter, the so-called. giant colon).
  It can be congenital, caused by the lack of ganglion cells in the section behind the dilated part of the colon) or acquired as a result of mechanical changes in the colon wall (e.g. as a result of long-term retention of fecal masses, bone scars in places of pelvic fractures, etc.).
• Shading deposits in the bladder.
• Liver Abnormalities:
  • Enlargement of the liver, which may be one of the symptoms of e.g.in. heart failure, Cushing's syndrome, diabetes, cancer, inflammation and many more.
  • Mineralization within the liver parenchyma.
  • Gallbladder enlargement, deposits or gas in the gallbladder.
  • Reduction of the liver, which is typical of cirrhosis or disorders of the portal liver system.
• Spleen abnormalities:
  • Enlargement of the spleen, which occurs as a result of: tumor, hypertension in the portal circulation, in animals with anemia or infection, with toxemia, hematoma, as well as spleen torsion.
  • Spleen torsion.
• Blurred image in the area of ​​the pancreas is often visible in pancreatitis, less often pancreatic cancer.
• Prostate enlargement, a fairly common condition in older, non-castrated male dogs.
• Enlarged uterus.
• Enlargement or reduction of the kidneys.
• X-rays are also used to control pregnancy and calculate the number of fetuses. It makes sense to do them after day 45 of pregnancy, because only at this point does the skeleton bone calcify and the fetal bones become visible.
  The radiograph allows you to determine:
  • number of fetuses,
  • their size,
  • location - that is, the ratio of the long axis of the fetus to the long axis of the mother,
  • posture - that is, the ratio of the spine of the fetus to that of the mother,
  • arrangement - the ratio of the moving parts of the fetal body to the stationary parts.

Radiographic examination of the bones

Radiographic examination of the bones

Indications for the study

Bone X-ray is one of the most common X-rays.

On its basis, it is possible to diagnose most diseases or abnormalities related to the locomotor system.

No wonder that the most common indications for its implementation include various symptoms related to the osteoarticular, muscular and ligamentous systems.

These include, among others:

• incorrect posture of the animal,
• lameness,
• limb saving,
• abnormal gait, limb shuffling,
• increasing the outline of the joints,
• sore joints or bones,
• thickenings, swellings or bumps in the limbs, spine, head,
• difficulty getting up,
• reluctance to move, apathy,
• injuries (fractures, dislocations),
• diseases of the teeth and paranasal sinuses,
• paresis, limb paralysis,
• radiological evaluation of hip and elbow joints in farm animals.

Positioning the patient for examination

The arrangement for examination is strictly dependent on the type of X-ray and the specific area that we want to assess.

Each area, structure (like a joint) or bone has strictly defined projections that absolutely must be applied to obtain a fully diagnostic X-ray image.

For example, in the event of an injury and suspected fracture, make 2 projections perpendicular to each other.

In turn, when x-raying the elbow joints towards elbow dysplasia, 3 x-rays are required:

• 2 medial-lateral (in one view the paw is placed quite loosely, and in the other - it is bent maximally in the joint),
• sagittal oblique.

Assessment of the radiograph

The veterinarian, when assessing the changes visible on the X-ray, meticulously and systematically assesses the following features:

A place of visible change

The assessor then locates exactly which part of the bone is affected by the abnormality (e.g. joint, bone epiphyses), as well as its individual layers (periosteum, medullary cavity).

The type of changes noticed

Whether there are atrophic or productive bone changes?

Are there any features of an aggressive or a benign lesion??

Shape of periosteal reaction

On its basis, it is possible to suspect an infectious, traumatic or neoplastic background of a given lesion.

Changing the shape of the bone cortex

When assessing a bone fracture, the doctor determines:

• what type of damage we are dealing with:
  • open fracture - when bone fragments communicate with the external environment;
  • closed fracture - no contact between the bone and its surroundings;
  • total fracture - that is, the fracture line runs the entire width of the bone (through its cortex on both sides of the bone);
  • incomplete fracture - e.g. fracture, fracture of the bone;
  • intra-articular fracture (the fracture line runs through the joint space) or extra-articular fracture (the fracture line does not run across the articular surface);
  • exfoliation of the base - that is, sliding off the base of the bone from its shaft;
• what is the nature of the fracture:
  • post-traumatic fracture - that is, one that occurred as a result of an injury;
  • pathological fracture - occurs when the changed bone (as a result of various clinical conditions, e.g. generalized bone atrophy, in the case of inflammatory or cancerous bone processes) is weaker than healthy bone. As a result, a pathological fracture occurs even with a slight load (one that would normally be physiological);
• fracture fracture lines:
  • we can deal with e.g. with transverse, oblique, spiral fracture, bone fracture, fragmentation of fragments, etc.;
• the degree of bone displacement and its direction, e.g.:
  • fracture without displacement,
  • displacement to the side,
  • displacement with extension,
  • setting the fragments at an angle;
  • number of bone fragments;
• an appropriate method of fracture stabilization;
• the course of the healing of the fracture;
• possible complications, such as.:
  • delayed union,
  • pseudo-pond,
  • abnormal union,
  • osteitis.

What abnormalities can be found from the bone radiograph?

• Fracture or disruption of the continuity of the bones;
• Healing of fractures - whether it is done properly or not.
  Sometimes there are complications that delay or completely prevent the broken bone from fusing.
  These complications include delayed union, lack of union (then the formation of the so-called pseudo-joint occurs) or bone deformation as a result of incorrect "attitude " or insufficient fracture stabilization.
  A control radiograph is performed 2 months after the fracture.
  Based on the x-ray, the radiologist can also estimate when the collapse has more or less occurred.
• Differentiating aggressive from benign changes.
  Any bone abnormalities found on x-rays must be evaluated for malignancy.
  There are some characteristic features that are specific to malignant bone tumors.
  The use of radiography in oncology is one of the most important diagnostic tests.
• Metabolic bone diseases, among which the most commonly recognized are:
  • osteopenia,
  • osteoporosis,
  • osteomalacia.
• Developmental disorders of the skeletal system, such as.:
  • polyunal dysplasia,
  • achondroplasia,
  • multiple bone spurs,
  • osteopetrosis,
  • fragility of bones and others.
• Bone diseases in adolescence:
  • premature ossification of growth cartilages.
    If (most often as a result of an injury to the growth cartilage) the bone growth stops in length, incorrect proportions are formed within the limbs concerned.
    The dog may have e.g. limbs disproportionately short in relation to the body.
• Hypertrophic osteodystrophy - occurs at about 2-7 months of age in fast growing dogs (large and giant breeds).
  Breeds where the disease is frequently diagnosed include:
  • great dane,
  • pointers,
  • German Shepherds,
  • ottweilers,
  • mastiffs,
  • Great Dogs of Bordeaux,
  • labradors,
  • boxers.
• Nutritional osteopathy - an overdose of calcium phosphate and vitamins (especially vitamin D) and the administration of high-energy food with an inappropriate composition may shorten the length of the limbs.
• Rickets - fortunately, a rarely diagnosed deficiency disease.
  The root cause is vitamin D deficiency, which reduces the intestinal absorption of calcium from the intestines.
• Aseptic necrosis of the femoral head (Legg-Calve-Perthes disease).
  This disease affects small breed dogs and appears in the period between 3 months of age. a 13. month of life.
  Predisposed breeds are:
  • Pekingese,
  • miniature poodles,
  • terriers,
  • dachshunds,
  • fox terriers.
• Panosteitis (juvenile osteitis) - quite frequent lameness in puppies of large and giant breeds, between 5. a 18. month of life.
  The breeds predisposed to its occurrence are:
  • German Shepherds,
  • dobermans,
  • golden retrievers,
  • labradors,
  • St. Bernard, but dogs of other breeds can get sick.
• Osteochondrosis dissecans (OCD) - a disorder of ossification in growing joint cartilage.
  It occurs in young dogs of medium and large breeds.
• Elbow dysplasia.
• Hip dysplasia.
• Congenital limb deformities (e.g. lack of fingers, additional fingers, underdevelopment of the distal part of the limb, etc.).
• Bone inflammation (e.g. purulent osteitis).
• Degenerative changes in bones and joints.

X-ray examination of the head

X-ray examination of the dog's head

X-ray examination of the bones of the skull shows only 80% of changes, while X-ray of other bones detects up to 100% of fractures.

Computed tomography is better used in the diagnosis of bone fractures of the skull cap.

Similarly, in the case of imaging lesions in the nasal cavity - radiographic examination may be too imprecise to visualize fine structures.

In the era of more and more common availability of more precise imaging tests (such as computed tomography or magnetic resonance imaging) in order to accurately diagnose disorders in the head area, determine their extent and nature, an X-ray image may no longer be diagnostically useful.

Indications for the study

• neurological symptoms such as:
  • head tilt,
  • walking in circles,
• nystagmus, strabismus, unevenly dilated pupils, no or no pupil reaction to light,
• bleeding from the nasal cavity, ear canal,
• otitis externa / middle ear
• runny nose, runny nose (varying in color and consistency), sneezing,
• discharge from the eyes (suspected diseases of the nasal cavity, mouth or paranasal sinuses)
• dental diseases,
• head injuries (fractures of the bones of the skull, jaw, etc.).

The most common clinical conditions shown on the x-ray image

• Fractures.
  As a rule, they arise as a result of an injury (fall from a height, traffic accident, impact).
• Otitis.
  Most often, as a result of chronic inflammation of the external auditory canal, the condition worsens and becomes inflamed with the middle and inner ear.
• Hydrocephalus.
  It is usually a congenital defect in which fluid builds up in the craniofacial area.
  Most often it concerns small breed dogs.
• Dislocation of the temporomandibular joint.
  It is manifested by instability of the mandible and difficult (or impossible) closure of the mouth.
• Occipital dysplasia - deformation of the occipital bone.
  Dangerous condition due to the risk of hernia of part of the brainstem.
• Benign or malignant neoplasms of the bones of the brain (e.g. osteosarcoma).
• Sinus abnormalities:
  • Fractures, most often caused by trauma.
    As a rule, these are open fractures.
  • Inflammation of the sinuses, which may be caused by a foreign body or by inflammation from the teeth or upper respiratory tract.
  • Tumors of the sinuses, usually of epithelial origin (adenocarcinomas).
• Nasal cavity:
  • inflammation, tumors; in the case of the examination of the nasal cavity, the symmetry of the nasal cavities, their airiness, the nasal septum, the condition of the turbinates and bones surrounding the nasal cavity are assessed.
• Teeth - X-ray imaging in dentistry is an extremely important and often a key part of diagnostics.
  The most frequently diagnosed disorders include:
  • Periodontitis - lowering the gum line and exposing the roots of the teeth until they fall out.
  • Fractures resulting from injuries or the biting of hard objects (stones, metal rods, etc.)
  • Apical purulent inflammation of the tooth root (periapical abscess).
    The infection can spread to the maxillary sinus, as well as form purulent fistulas that break outward.
  • Metabolic diseases (e.g. as a result of vitamin D and calcium deficiency).
  • Tumors of the teeth or surrounding tissues.
  • Shading foreign bodies in the mouth.

Radiological examination of the spine

X-ray of the spine is one of the first animal studies after accidents.

However, it can detect many other vertebral disorders, both acquired and congenital.

Indications for X-ray examination of the spine

• trauma (fall from height, traffic accident, etc.),
• lameness,
• weakness and reluctance to move with fever,
• paresis, paralysis, incoherence,
• soreness in any part of the spine,
• incorrect body posture,
• problems with getting up and walking,
• skin hypersensitivity,
• excessive stiffness of the limbs,
• distortion of the spine line,
• urination and / or stool disorders,
• disturbances of consciousness.

What diseases can be detected on the basis of an X-ray of the spine?

• Acquired diseases of the spine, the most common of which are post-traumatic, inflammatory or degenerative changes:
  • Degenerative changes that may affect various elements of the spine (not only the vertebrae themselves, but also the intervertebral discs, joints and other connections).
    They can be:
    • Degenerations of the cartilaginous joints of the spine, such as. degeneration of intervertebral discs (discopathies), spondilosis deformans (the so-called. parrot beaks),
    • Synovial joint degeneration (arthrosis) - most often in the lumbar spine.
      These conditions cause great pain.
    • Degeneration of the fibrous connections of the spine, e.g. disseminated ossification of the skeletal system (disseminated hyperostosis).
      The disease consists of excessive bone growth at the site of attachment of ligaments to the bone.
      Occurs in large breed dogs (especially boxers).
• Post-traumatic changes, such as fractures, dislocations.
  X-ray examination in patients with suspected spinal injury should be performed very carefully.
  The first photo is taken in a relaxed position, without stretching the animal too much
• Inflammation of the spine.
  The nomenclature also differs depending on the structure affected by the inflammation.
  We can deal with:
  • Spondylitis - if the vertebral body is inflamed.
  • Discospondylitis - if the inflammation affects 2 adjacent vertebral end plates and the intervertebral disc.
  • Discitis - if the inflammation affects the intervertebral disc itself.
    However, this condition is rarely detected on an X-ray, so you should use magnetic resonance imaging or computed tomography.
• Tumors.
  These can be benign or malignant primary neoplasms, as well as metastatic lesions.
  They can appear in any part of the spine.
• Syndromes:
  • Peak-rotational instability.
    It is favored by developmental defects of the spine, such as. underdevelopment, missing or distortion of a tooth of the rotary vertebrae.
    These changes put pressure on the spinal cord in this area.
    The disease occurs in small breed dogs (miniature poodles, Yorkshire terriers, Shih-tzu)
  • Wobbler syndrome - cervical instability.
    It is a combination of all diseases that can cause narrowing of the spinal canal and pressure on the spinal cord in the cervical region.
    The disease most often affects large breed dogs (e.g. Doberman (Great Dane), but it can also appear in smaller breeds.
    The reasons that can lead to this syndrome are:
    • abnormal development of the cervical vertebrae,
    • osteochondrosis,
    • damage to the vertebral joints or microtraumas causing instability.
  • Horse tail syndrome (cauda equina syndrome) - this includes all diseases that cause a narrowing of the lumen of the spinal canal in the lumbosacral region (from 7. lumbar vertebra to 1. sacral vertebra).
• Congenital diseases that can affect the shape of the spine and cause it to curve, e.g.:
  • lordosis,
  • kyphosis,
  • scoliosis.
• Peak-rotational instability of a developmental nature.
• Developmental disorders of the spine:
  • sacralization, lumbarisation - these are disorders within the spine caused by the presence of the so-called. transition vertebra.
    Lumbarization occurs when the first sacral vertebra has the features of a lumbar vertebra, and sacralisation occurs when the last lumbar vertebra has the features of a sacral vertebra.
    This may result in an oblique position of the pelvis in relation to the spine, which in turn may favor the development of hip dysplasia.
  • Block of the last pair of ribs with the thoracic vertebra.
    A developmental defect consisting in the fact that the last ribs "merge" directly with the vertebrae.
    Rather of no clinical significance.
  • Spina bifida - in embryonic development, the upper part of the vertebral arch is not fused.
    This condition can lead to a meningeal or spinal hernia.
  • Semicircle - Abnormal development of the vertebral body.
    A very common feature, found on X-rays of English bulldogs and French bulldogs.
    An incorrect, wedge-shaped vertebrae can lead to kyphosis or lordosis.
  • Congenital block of vertebrae - when the bodies of 2 or more vertebrae fuse fully or partially together.
    It is common in dachshunds but also in cats.

Radiological examination of the joint

Indications for the X-ray examination of the joint

• lameness, reluctance to move,
• problems with getting up and walking,
• abnormal gait, limb sparing,
• painful, hot, and / or swollen joints (or joint),
• injuries within the joints,
• reluctance to move with the accompanying fever, apathy and lack of appetite,
• radiological evaluation for dysplasia of the elbows or hip joints.

Positioning the patient for examination

As standard, two projections are made to assess the joint:

• side,
• sagittal.

Additionally, they may apply:

• oblique positions:
  • side,
  • medial,
• position when loading the joint, in flexion or extension (i.e. forced pictures).

It all depends on the type of pond.

The most common are medial-lateral and sagittal x-rays.

Often, short-term anesthesia is necessary for the correct positioning of the patient.

Radiological evaluation of the joint

According to radiologists, when assessing joints, one should pay attention to the following elements:

• Bone alignment with each other.
  The bones should be lined up in series.
  If there is a visible disturbance of this position, it is possible to rupture or strain the ligaments.
• Soft tissues adjacent to the examined joint.
  Their contours, continuity, and possible swelling or disappearance are assessed.
  Pay particular attention to whether any foreign bodies, calcification or air are visible.
• The shape and bone structure of bone epiphyses (chronic degenerative changes can manifest as thickenings under the articular cartilage or small bone cysts).
• Pond space.
  The picture may show a narrowing of the articular space (which may indicate the destruction of articular cartilage) or a widening of the articular space (this happens with ligament injuries or e.g. outflow into the joint cavity).
• Periarticular structures.
  Joint edges are assessed with particular emphasis on possible osteophytes, joint edge sharpening, avulsive fractures (i.e. detachment of a bone fragment at the site of ligament attachment).
• Distribution of lesions in the pond. If the lesions are symmetrical in several joints, it may be due to the presence of a systemic disease (e.g. rheumatoid arthritis).

The most frequently diagnosed diseases of the joints

• Inflammation of the joint (arthritis).
  Joint inflammation is most often the result of an infection.
  This may occur as a result of the joint injury itself (e.g. penetrating wounds), surgery, or the spread of infection from nearby tissues or through the blood.
  A separate group of arthritis are the so-called. aseptic inflammations, which in turn often accompany immune diseases (e.g. rheumatoid arthritis, lupus erythematosus). Inflammation can also occur in the course of Lyme disease.
• Osteoarthritis.
  It is the most common type of joint disease in animals.
  The occurrence of degenerations within the joint is a consequence of many abnormalities and diseases, but in the most general terms, it can be said that they develop on the basis of disorders in mechanics.
  This can happen with:
  • All kinds of congenital deformities of joints and bones, where degenerative changes occur as a result of incorrect and uneven loading of the joint surfaces.
    This happens with hip dysplasia or congenital distortion of the limb axis.
  • Acquired deformities of joints and limbs, e.g. abnormal fusion of a bone fracture or as a result of aseptic necrosis of the femoral head.
  • After an intra-articular fracture.
  • After inflammation of the joint.
• Fortunately, joint cancers are rare.
• Joint injuries.
  One of the most common causes of lameness and one of the main indications for x-rays.
  The most common injuries of the joints are:
  • twist,
  • sprain,
  • subluxation,
  • intra-articular fracture.
• Separating osteochondrosis (osteochondrosis dissecans - OCD).
  It is a disease that occurs in young dogs of rapidly growing breeds during the period of bone growth.
  Without going into too much detail, it can be said that its cause is a disorder of ossification in the articular cartilage, leading to its excessive thickening.
  As a result, the nutrition of the cartilage at this site is significantly impaired.
  This fragment may then break off and move around the joint as a so-called. joint mouse.
  OCD can affect the joint:
  • brachial,
  • elbow,
  • knee,
  • jumping.
• Elbow dysplasia.
  It includes all adolescent diseases related to the elbow joint that lead to its degeneration.
  The most common are:
  • osteochondrosis dissecans (OCD) - occurs in medium and large breed dogs, usually between the ages of 4 months. a 10. month of life;
  • fragmentation of the medial coronary process of the ulna (FCP);
  • non-fused accessory appendix (UAP).
• Hip dysplasia (HD).
  It is a multifactorial developmental disorder of the hip joint.
  It occurs most often in dogs of large and giant breeds (over 20 kg), less often it is diagnosed in small breeds.
  An interesting fact is that hip dysplasia also affects cats.
  The most predisposed breeds are:
  • St. Bernardine,
  • Newfoundlands,
  • mastiffs,
  • labradors,
  • Bernese Mountain Dogs,
  • rottweilers,
  • great dane,
  • German Shepherds,
  • setters.
• Knee injuries:
  • detachment of the tibial tuberosity;
  • dislocation of the kneecap;
  • rupture of the kneecap simple ligament;
  • rupture of the ligaments of the tibial joint.
• Fractures within the joints.

X-rays using contrast

X-rays using contrast

Sometimes an x-ray image alone is not enough to precisely identify changes in the body.

Contrast, or contrast agent - is a substance that weakens X-rays more or less in relation to the body tissues.

As the name suggests, it is used to contrast a given organ or area.

Despite the fact that the examination with the use of contrast is less and less used (thanks to the widespread access to such examinations as ultrasound, computed tomography or magnetic resonance imaging), it is still used in radiography.

Contrast agents can be:

• Negative - air, carbon dioxide, noble gases.
  They weaken the X-rays to a minimum extent.
  They are most often used to test the bladder or the gastrointestinal tract (in a two-contrast test).
• Positive - Absorbs X-rays more than tissues.
  The two main elements that make up them are:
  • iodine,
  • bar.

Contrast testing with barium sulphate (popularly known as barite) is primarily used to assess the gastrointestinal tract.

Iodine agents are used to examine body cavities (e.g. spinal canal), often also for examining the urinary system.

Contrast examination of the gastrointestinal tract

A significant number of diseases affecting the esophagus, stomach and intestines is not diagnosed on the basis of x-ray examinations.

Therefore, in order to visualize the lumen of the gastrointestinal tract, X-ray examination with contrast is performed.

The contrast agent (most often Baryta) is administered orally (to assess the esophagus, stomach and small intestines) or rectally (to assess the large intestines).

Indications for contrast gastrointestinal examination

• vomiting,
• diarrhea,
• lack of appetite and weight loss,
• downpour,
• blood in the stool,
• suspicion of a non-shading foreign body in the digestive tract,
• defecation disorders.

Preparation of the patient

A minimum of 24-hour fast before the contrast test,

If necessary, an enema 3 and 1 hours before the examination.

Premedication should not be administered.

The patient must consciously swallow the contrast agent, and the anesthesia causes motor disturbances in individual sections of the gastrointestinal tract.

This may be associated with the risk of choking with the preparation, and in the best case prolonging the passage of the contrast through the individual digestive system.

Before administering a contrast agent, always take a visual inspection of the abdominal cavity and make a preliminary assessment.

An empty digestive tract is a necessary condition for the administration of contrast.

If the review X-ray shows changes that threaten the patient's life and are the cause of the primary disease, the examination is abandoned.

Contrast passage through the gastrointestinal tract

Pictures are taken just before administering the preparation, and then immediately after it is administered.

Then 15, 30 and 60 minutes after administration.

Then every hour until the colon is visualized.

The stomach should be emptied of the contrast medium after 4 hours.

Baryte (contrast agent) begins to leave the stomach after 10-15 minutes, and after 30 minutes it should be in the duodenum.

The small intestine is filled with barite within 2-4 hours of administration.

The intestines empty after 8 hours.

In general - to assess gastric emptying and intestinal passage - photos should be taken every hour, but in practice it is often impossible for technical, time, financial and other reasons, therefore this time is usually extended to 2-3 hours.

Barite must not be administered when

• the patient has a full stomach,
• the animal is in poor general condition,
• the animal is pharmacologically sedated,
• in acute and infectious diseases,
• if foreign shading bodies (e.g. undigested bones), contrast is not required.

What can be diagnosed with a contrast test?

• Esophageal Abnormalities:
  • Inflammation of the esophagus.
    Inflammatory changes in this place are most often caused by ingestion of a corrosive substance or chronic gastric reflux.
  • Foreign body or narrowing of the esophagus.
  • Esophageal diverticulum.
  • Giant esophagus.
  • Patent ductus arteriosus and other abnormalities of the vascular ring of the base of the heart.
• Abnormalities related to the stomach:
  • Stenosis of the pylorus, which may be caused by contraction or hypertrophy of the pylorus.
    Pyloric spasm occurs when the pyloric muscles are overstressed.
    It can accompany intestinal inflammation, renal and hepatic colic, uremia or toxemia.
    Sometimes too acute inflammation leads to a strong contraction of the pylorus.
    The main symptom is vomiting partially digested food, up to 2-3 hours after eating.
    Pyloric hypertrophy, in turn, can be congenital or acquired.
    Neoplastic tumors can even lead to obstruction of the pyloric canal.
    The dog most often vomits immediately after drinking or eating it, sometimes after an extended period of time.
  • Stomach ulceration.
    Currently, there are other, more detailed diagnostic methods for diagnosing gastric ulcers, but sometimes they can be diagnosed on a radiograph after administering a contrast agent.
    The same is true of ulcerative colitis.
  • Non-shading foreign bodies.
    These are items that cannot be seen in the overview X-ray.
    Common, frequently ingested foreign bodies such as stones or bones are generally well visible on radiographs.
    Metal objects (shot, nail, needle) also shade a lot, so they are easy to see in the X-ray image.
    However, some items, such as foil, various fabrics, threads, etc. may go unnoticed when assessing a regular radiograph - they just shade similar to the surrounding soft tissues.
    Therefore - in order to detect them - it is sometimes necessary to perform a contrast test.
  • Stomach tumors.
    Quite often diagnosed in dogs and cats.
    Adenocarcinoma is a typical cancer of the stomach, but it is also possible:
    • lymphosarcoma,
    • fibrosarcoma,
    • leiomyoma.
• Abnormalities concerning the small intestines:
  • Inflammation of the intestines.
  • Small intestinal obstruction.
    There are many reasons for intestinal obstruction.
    Among them, the most common are:
    • obstruction of the intestine with a foreign body,
    • tumor oppression,
    • intestinal adhesions,
    • intussusception,
    • looping intestines,
    • displacement of the intestines into the hernial sac.
• Abnormalities concerning the large intestine:
  • Ulcerative colitis (visible during colonography - i.e. contrast administration through the handpiece).
    It is quite common in boxers and German shepherds.
  • Giant colon.
    To its creation predisposes:
    • long persistence of feces,
    • neoplastic changes,
    • pelvic deformities (after injuries, fractures),
    • neurological disorders (can accompany cauda equina syndrome).
• Tumors.
  Older dogs are most often affected.
  The two main types of neoplastic lesions are adenocarcinomas and leiomyomas.

Contrast examination of the urinary system

In the X-ray contrast examination, different contrast agents and the way of administering the contrast are used, depending on which elements of the urinary system we want to assess.

Pneumocystography

Pneumocystography (negative cystography) - introducing a contrast medium into an empty bladder, e.g. air.

Carbon dioxide or some noble gas can also be introduced.

Contrast - after emptying the bladder - is administered through a catheter.

The indications for pneumocystography are:

• suspected chronic inflammation of the bladder wall,
• bladder wall tumors,
• suspicion of non-shading stones in the urinary bladder,
• suspicion of dislocation of the bladder (e.g. with a perineal hernia or a significant enlargement of the prostate gland),
• suspected rupture of the bladder wall (eg. after a traffic accident).

Cystography

Cystography - the introduction of a positive contrast agent into the bladder.

The indications for cystography are:

• bladder cancer (abnormal shape of the bladder wall when examined),
• displacement of the bladder,
• assessment of the mucosa of the bladder and urethra (ultrasound is a more sensitive test that provides more information).

Double contrasting of the bladder

The use of both types of contrast (positive and negative) allows for a more accurate assessment of the bladder mucosa.

Retrograde urethrography

Retrograde urethrography - the introduction of a contrast agent (air or positive contrast) into the urethra.

Urethrography is primarily used to evaluate the urethra, but it has also found application in the examination of the prostate.

The indications for the examination are:

• thickening of the urethral wall,
• tumors,
• non-shading stones,
• discontinuity of the coil wall,
• suspicion of prostate cancer.

Intravenous urography

Intravenous urography - i.e. the intravenous administration of a positive contrast agent, which is then excreted by the kidneys.

Urography allows you to see the kidneys, ureters and bladder.

The indications for the examination are the assessment of:

• renal excretory function,
• the size and shape of the kidneys (currently being replaced by computed tomography and magnetic resonance imaging),
• the shape of the renal pelvis and their recesses,
• shape and patency of the ureters,
• the walls of the bladder.

Preparation of the patient for the contrast test:

Before administering a contrast agent (especially when administered intravenously), a blood test is necessary to qualify the patient for urography.

The smallest scope of tests is a morphological examination and determination of urea and creatinine levels.

Minimum 12-hour fast.

Emptying the digestive tract of food, gas, fecal masses (enema).

The course of X-ray examination with contrast

1. Intravenous administration of a contrast agent.
2. And the photo is taken immediately after injection.
3. 2nd photo - after 5 minutes. Now the contrast agent should be in the renal pelvis.
4. Photo III - 15 minutes after the injection, the contrast reaches the ureters (if there are no obstacles).
5. IV photo after 30 minutes.
6. 5th photo after 1 hour.
7. VI photo after 2 hours.

If we want to assess the ureters and bladder, or if the excretion of contrast by the kidneys is delayed, photos are additionally taken every 20 minutes.

In all x-rays, the course of the ureter is assessed, whether it flows equally through both kidneys, pelvis, urinary and finally flows into the bladder.

Contrast tests within the spine

Myelography

Myelography, i.e. a contrast test of the spinal cord.

The most widely used is subarachnoid myelography that is, administration of a contrast agent to the subarachnoid space of the spinal cord, and then taking a series of x-rays.

The needle is inserted into the cerebellospinal reservoir between the occipital bone and the first cervical vertebra (just behind the animal's skull).

If the lesions are located in the posterior part of the body, the puncture is made between the final lumbar vertebrae:

• in a dog between 6 months of age. a 7. lumbar vertebrae,
• in a cat between 5 months of age. a 6. lumbar vertebrae.

After puncture, iodine contrast agent is administered.

First, a lateral radiograph is performed, then a dorso-abdominal or abdominal-dorsal x-ray can be taken.

Indications for myelography:

• narrowing of the intervertebral space, visible in the image aimed at a given section of the spine,
• compression (pressure on the spinal cord),
• no changes in a typical radiograph, but neurological deficits are present,
• suspicion of compression in several places of the spine.

Preparation of the patient for the contrast test

What a myelography the patient should be especially prepared for 2 reasons.

Ensure the best possible quality of the X-ray image and minimize the risk of changes that could obscure the image (e.g. presence of fecal masses in the colon or rectum).

Secondly, the animal will receive sedation drugs, so it should be on an empty stomach.

In order to prepare the patient for the examination, it is necessary to:

1. 24 hours before the test, administer semi-liquid, easily digestible food
2. Fast for at least 12 hours prior to testing.
3. Lactulose may be given to facilitate bowel movements.
4. In justified cases, an enema is used.

Purpose of the study

Entering the contrast allows the assessment of the contrast passage in the subdural space.

Under proper conditions, the contrast agent should fill the meningeal sac on both sides of the spinal cord.

Any narrowing or widening of the lumen (visualized by contrast) of the meningeal sac gives clues as to the type and location of lesions compressing the spinal cord.

Complications of myelography

The test is invasive and the animal's guardian must know about it.

It is obligatorily performed under sedation.

Unfortunately, there are complications of myelography, including:

• nerve tissue damage,
• seizures,
• pseudo-epileptic seizures,
• heart problems,
• breathing disorders,
• shock,
• the death of the animal.

Epidurography

It is a contrast test of the light of the spinal canal.

It is most often used to diagnose cauda equina syndrome.

Epidurography is easier and safer than myelography.

In fact, it repeatedly becomes an undesirable effect of myelography when the contrast agent is not deposited into the subdural space.

The contrast agent is administered between 3. sacral vertebrae, and 1. caudal.

Discography

It is used to assess the nucleus pulposus in the intervertebral space between 7 months of age. lumbar vertebrae and 1. cross.

Contrast is administered directly to the intervertebral disc, and the aim is to visualize any herniation of the disc.

X-ray in dogs and cats - price

X-ray of a dog and a cat - price

X-ray examination is a relatively inexpensive examination because it costs one photo X-ray prices oscillate between PLN 30 and PLN 60.

However, the total cost can increase significantly as it depends on factors such as:

• The need for anesthesia or sedation.
  In such a situation, the price per photo increases by as much as 100-200 PLN - depending on the size of the animal (i.e. the amount of the drug).
• The number of x-rays needed.
  In the case of a single radiograph, there is no problem, but when taking a series of x-rays (as is the case, for example, with a contrast test), the total cost of x-rays soars up.
• Kind of X-ray.
  Due to the better quality of x-rays made with digital cameras, the price of such radiographs is higher.

The cost of the visit, a possible clinical trial and the drugs used should also be added.

Which is not good for an X-ray?

X-ray examination has some limitations.

It does not always show changes, especially if they are minor.

With the use of x-rays, we will not assess the internal structures of organs or tissues, we will not see what is happening in the heart, and we are not able to accurately examine certain areas of the body, such as. throat.

In the radiograph of joints - despite such a wide use of X-ray - we will not show, for example,.:

• damage to the meniscus,
• rupture of the joint capsule,
• ligament tears.

On the other hand, the chest X-ray will not show minor abnormalities in the pleural cavity.

For example:

the smallest amount of fluid present in the pleural cavity that can be detected by X-ray is 50 ml (small dogs) to 100 ml (large dogs).

To evaluate these and many other structures, other diagnostic methods are used, such as testing with the use of:

• • computed tomography,
  • magnetic resonance imaging,
  • usg.

Therefore, the veterinarian has a great responsibility to skilfully select the type of examination, taking into account the suspected disease or clinical condition, using his knowledge and experience.

Summary

X-rays are extremely useful in identifying a wide range of health problems, from foreign bodies and bone fractures to cancer and life-threatening conditions.

The importance of x-ray examination cannot be overstated, and even today, more than a century after Wilhelm Xentgen's discovery of radiation, radiography still tops the list of the most commonly used additional examinations.

Even despite the fact that newer, more and more sophisticated diagnostic methods are already available in veterinary medicine, examination with the use of X-rays is used to diagnose the majority of diseases.

However, on the other hand, great emphasis must be placed on the fact that x-ray imaging will not cure the animal.

Yes, radiotherapy has found wide application in the treatment of cancer and this is one of its therapeutic functions.

However, in the face of the very widespread ordering of x-rays by doctors, it is difficult to resist the impression that it is often simply abused.

The X-ray is to confirm the doctor's conclusions based on the clinical examination and other, less invasive diagnostic methods.

It should not be treated as:

let's take a picture and see what happens there.

Not the way.

X-rays are harmful and the use of research using it should be well-founded.

All information in this article comes from materials compiled by experienced radiologists.

They are the ones who best know the nature of x-ray radiation, its effects and application.

All warnings regarding its harmfulness and recommendations on how to protect against radiation should be deeply respected, and at the same time strictly followed in - even the smallest - veterinary surgeries.

There was no hint of exaggeration in any of the above safety statements.

X-ray radiation has a negative effect on tissues and organs, so you should do everything to expose yourself and your client as little as possible.

Sources used >>