Читать книгу Fractures in the Horse - Группа авторов - Страница 130

CT is an excellent determinant of bone morphology but does not provide information about biological activity. This can be inferred by interpretation of the complement of morphological changes but does not reflect the level of activity as seen in nuclear medicine studies (scintigraphy or positron emission tomography [PET] scanning) or provide a visual map of intra‐osseous fluid accumulation as shown by fluid‐sensitive MRI sequences.

When imaged with X‐ray technology, soft tissues have low intrinsic subject contrast thus generating images with low contrast resolution. This is further exacerbated when soft tissues abut high‐density bone surfaces, e.g. cartilage over subchondral bone or the deep digital flexor tendon over the navicular bone. Modern and appropriate image processing mitigates these effects and, in general, soft tissue imaging is fair to good in conventional scanners. Contrast media can also help by increasing subject contrast and should be considered when excellent bone and soft tissue or cartilage imaging is required.

Availability of CT remains limited and most require general anaesthesia. Standing CT offers shorter acquisition time than MRI; however, the reliance on changes in bone density before a discrete fracture line can be identified means, that as a screening tool, there remains the possibility of false negatives.