Non-skeletal scintigraphy of the horse: indications and validity.

Gamma scintigraphy is an established imaging modality in the horse and is principally utilised to investigate skeletal disease using bone-seeking radiopharmaceuticals. However, depending on the radiopharmaceutical and imaging sequence, scintigraphy can be used to investigate disease in virtually any organ system. In this article the indications and validity of scintigraphy as a clinical diagnostic tool to investigate non-skeletal disease in the horse are reviewed. These indications include: investigation of dental disease, identification of inflammatory foci, vascular lesions, muscle and tendon pathology, assessment of physiological function of the lungs, gastrointestinal tract and other organs. Some of the techniques described for use in the horse have not been validated fully and as a result non-skeletal scintigraphy requires further investigation and validation using well-designed prospective studies. Such information can be used by clinicians to make informed decisions regarding the clinical and economic issues associated with a specific scintigraphic technique and may help when interpreting the results.