34th Annual Scientific Meeting proceedings

Objectives:

Conducting imaging studies of the thoracic and abdominal cavities of horses is challenging. Previously, CT examination of the mid-thoracic region, thorax and abdomen has been performed only in miniature breeds. The aim of this study was to determine the feasibility of full thoracic and abdominal CT examination in small and medium sized horses.

Methods:

CT examination of three mature horses weighing 320, 360 and 460 kg was performed in dorsal recumbency immediately after euthanasia, using a helical 16-slice multidetector scanner with a 90 cm diameter gantry. For scanning the abdomen, the carcasses were positioned with the hindlimbs entering the gantry first (caudal position). Then the horses were repositioned headfirst into the gantry for more cranial segments (cranial position), CT images were subjectively evaluated.

Results:

CT examination of the entire thoracolumbar region, thorax and abdominal cavity could be performed in five separate parts in the two larger horses and in three parts in the 320 kg carcass. In the caudal position the examination focused on the abdomen and could be performed in two or three parts, respectively. The thorax could be examined in one or two different sections in the cranial position. The abdominal and thoracic organs could be distinguished well; the thoracolumbar vertebrae were visible accurately.

Conclusions:

Based on our pilot study we assume that in vivo the CT examination of horses might be achievable under general anaesthesia. Caudal positioning of horses could enable preoperative colic diagnostics, and the cranial position might allow examination of the mid-thoracic spine in suitably sized horses.