An X-ray machine can make radiographic pictures of the inside of the body using X-rays. Because of their high penetrating ability this technique is commonly used to look at the bones, but other parts of the body such as the longs can also be imaged using this technique. Nowadays radiographic examination has made huge progress introducing digital radiography. Images can be magnified, contrast can be enhanced or diminished and information can be exchanged quickly and easily by computer.
Applications of radiographic examination
This technique is most often used in the orthopedic examination, we can image fractures, osteoarthrosis, deviations in alignment of the bones, bone cysts, …all causes of lameness in horses. Radiology can also be used to image the skull and look at the teeth. When examination of the respiratory tract is needed radiographs can be made to image the lungs and trachea. Because this technique puts all information in one plane, multiple radiographs taken in different angles are necessary to get to an accurate diagnosis. In most cases one picture is not sufficient. In a prepurchase examination a standardized set of radiographs is made according to the wishes of the buyer and the discipline of the horse (see prepurchase examination).
Scintigraphy
In nuclear diagnostics or scintigraphy radioactive material is injected into the horse and a scanner is used to look for areas with increased radiopharmaceutical capture of the radiation. Most commonly these are areas which consist of inflamed or damaged tissue and therefore capture more radioactive material than healthy tissue. Scintigraphy is mostly used for areas of the horse of which we cannot make X-rays or ultrasound images or when the veterinarian is not certain where the painful area is located. This technique offers a lot of possibilities and advantages in the orthopedic examination, even the smallest bone change of 2% can be found using this technique. This is in contrast to radiographs which can only determine a change in the bone of more than 40%. This is why scintigraphy is also used as a screening method for early pathologies.
How does scintigraphy work?
If possible the horse is lunged before the radioactive material is injected in order to enhance the blood flow in the horse’s legs. This is necessary to make sure that the radioactive material is well absorbed into the whole body. After lunging the legs are wrapped and the feet are placed in hoof sacs to make sure there is no contamination by urine or feces. Subsequently the horse is injected with the radioactive material. After that the horse is put in a stable for 2 hours to let the radioactive material be distributed throughout the whole body.
Before entering the examination room the horse is sedated slightly and hoof sacks and bandages are removed.
A scan can be made of the complete horse or only a part of the horse such as the head or the hind legs and the back of the horse, it is also possible to scan just a very small part of the horse when a control scan is performed as an evaluation after certain therapy.
The areas that need to be examined are scanned for one minute in which the horse must stand perfectly still. In contrast to radiographic examination scintigraphy gives us information about the present state of the body not the past.
All scintigraphic images made at Lingehoeve Diergeneeskunde are sent to the United States the same day. They are studied by Prof. P. Steyn who is a certified American radiologist specialized in scintigraphy. The next morning the final results are available at Lingehoeve Diergeneeskunde and the client is being notified with a complete report.
In the mean time the horse has to stay quarantined at the clinic for 2 to 3 days to make sure there is no residual radiation when the animal is going home.
Depending on the diagnostic findings additional examination by radiographs or ultrasound may be necessary. When the final report is given to the owner our veterinarians will discuss all possibilities regarding treatment, rehabilitation and customized shoeing. In the event of a referral the referring veterinarian will also get the scintigraphy report so that further treatment can be done at home by the owner’s own veterinarian.
Ultrasound
Ultrasound is a technique that uses sonographic waves witch are not audible by the human ear. The device is put on the skin of the horse and emits its waves. The returned waves or echo’s are captured by the machine and are translated into an image on the screen by the computer. These sonographic waves are completely harmless for humans and animals and can be used safely to image tendon, ligaments, joints and bone surfaces.
Ultrasound on shoulder
Ultrasound is a very sensitive technique used to diagnose all sorts of soft tissue lesions mostly in association with a lameness examination in horses. Bony structures cannot be penetrated by ultrasound waves, but the bone surface can be seen in detail even more sensitive than radiographs and this is very helpful in diagnosing a lesion at its attachment to the bone.
This technique can also be very valuable in the examination of the abdomen in horses and foals suffering from colic. Even the chest cavity can be imaged using ultrasound, for instance in coughing foals.
Ultrasound is indispensable in the gynecological exam of the uterus, cervix and ovaries. The technique can be used in every routine examination of a mare but also for mares with problems getting pregnant. You can also use the transabdominal approach to image the unborn foal.
Ultrasound is a technique which is easy to use and indispensable in the daily veterinary practice.