- A high definition film-screen combination is required.
- A grid is not required.
- kV should not exceed about 50.
- Soft tissues should be included.
- General anesthesia or sedation is required.
- The film should be correctly exposed and developed, and free from movement blur and artifact.
- The anatomical marker must be clearly visible, along with the patient's identification, the date, and the name of the hospital or practice.
- (Figs. 1-2)
- Fracture .
- Dislocation [Carpus: shearing injury] .
- Neoplasia: bony , or soft tissue invading bone [Synovial sarcoma] .
- Carpal valgus/varus but full length radius and ulna views including the carpus may be preferable.
- Foreign bodies.
- Arthritis .
- Paronychia .
- X-ray machine.
- Cassettes with high definition screens.
- Processing facilities.
- Immobilization and positioning aids: sandbags, foam wedges, tying tapes.
- Protective clothing (lead-rubber aprons).
- High output X-ray machine.
- Rare earth high definition screens.
- Automatic processing facilities.
When looking for subtle abnormalities it can be helpful to use dental film, or a cassette designed for human mammography. This is a very high definition, high contrast system with only one screen in the cassette, utilizing single-sided emulsion film. It has been quite widely used in equine radiography, but it should be remembered that it is designed for use at very low kV values (around 30kV) and optimum perfomance will be achieved around this level. It naturally requires higher mAs values than twin-screen systems.
- X-ray film.
- Pharmaceuticals for chemical restraint.
- Dependent upon the method of chemical restraint (GA or sedation).
Reasons for treatment failure
- Inadequate sedation.
- Poor technique: inaccurate positioning or centering, wrong exposure factors.
- The most common positioning problem is rotation of the carpus and foot away from either the true lateral or the true dorsopalmar position. To avoid this, it is important to position from the proximal end of the limb. If the elbow is right, the foot will lie as required. Liberal use of foam wedges and sandbags is important in successfully maintaining the positions.
- Poor processing.
- Equipment failure.