What does scintigraphy mean?
Gamma scintigraphy is a well established imaging modality, which in equine practice is predominantly used in the investigation of unclear lameness and suspected musculoskeletal problems.
How does scintigraphy work?
A harmless radioactive marker (Tc 99m) is applied intravenously. Within a short period the radioisotope, which is bound to a carrier (Oxidronacid, HDP), accumulates in areas of the skeleton with increased bonemetabolism. These points of radiation (“hot-spots”) are detected by a special x-ray camera and can be pictured by a computer. Nowadays a general anaesthesia isn`t necessary, the patients will only be lightly sedated. After the examination the horses have to stay in the clinic for another 48 hours because of the emitted radiation.
What is the indication for scintigraphy?
There are 3 typical reasons for a scintigraphic examination:
1. When the origin of lameness can not be located by local anaesthesia or is suspected to be in the neck, the back or the sacroiliac joint.
2. When it`s not possible to anaesthetize a horse, especially in the hind limbs.
3. When local anaesthesia is contraindicated, for example in cases of severe lameness where a fracture or fissure is suspected.
How secure is the value of scintigraphic results?
Where the bone metabolism is increased the radiopharmacon will accumulate and emit radiation. These points of high radiation can be seen in the scintigraphic image (“hot spots”). Nevertheless it is important to interpretate the scintigraphy together with the results of the clinical examination to prevent false-positive findings.
Do the patients have to be specialy be prepared for the examination?
It would be best if the patients could be lunged 2 to 3 days before the scintigraphic examination to save an equal circulation in the affected region of the body. It would also be good to put on stable bandages on the horses legs.
For further information you can call Dr. Mark Zengerling