Radiography and ultrasound of the equine neck

Lateral radiographs of the neck are relatively easily obtained with a high-powered portable X-ray generator, typically 70 kilovoltage peak (KvP) and 0.15 seconds. However, images of the base of the neck and oblique views may require a higher-powered, ceiling mouted generator, up to 90kVp and 45 milliampere seconds.

Acquisition of laterolateral views of the neck in the standing horse is straightforward. The horse should be stood squarely on a firm level surface, with the neck straight relative to the body and the head resting on a head stand or shavings bale. Tilting of the head or bending of the neck results in cervical spine obliquity, limiting the diagnostic quality of the radiographs. Sedation is required to prevent the horse being startled by equipment and blinkers may be useful. A rope halter should be used for projections encompassing the poll. A plate-holder and a generator stand should be used to ensure radiation doses to personnel are minimised. A grid can be beneficial, as this reduces scattered radiation and improves image quality. However, unless this is in a fixed ‘Bucky’ system, it can be challenging to maintain the x-ray beam perpendicular to the grid, which is essential for image acquisition. Modern digital radiography systems may include digital noise suppression, which may improve image quality without the need for a grid.