Observations on the potential role of oesophageal radiography in the horse.

Radiological features of the oesophagus of 7 normal horses and 13 with oesophageal lesions are described. The use of barium sulphate as a contrast agent and the techniqes of its administration are discussed. It is suggested that chronic intermittent oesophageal impaction with food material was a predisposing factor in the development of a localised oesophageal dilation in 3 horses and that one other probably resulted from an injury. A similar dilatation was seen which resulted from oesophageal constriction by a vascular ring. Megaoesophagus was seen in 2 ponies associated with grass sickness and a third case had a more localised ares of dilatation in the distal thoracic oesophagus. Other abnormalities recognised included slow passage of food material through the cranial oesophagus which was seen in 3 horses; one as a sequel to a laryngoplasty operation, the second was the probable result of chronic aerophagia and the third was a congenital abnormality. Oesophagoscopy was found to be a useful adjunct to radiography in the diagnosis of oesophageal disorders in horses.