Radiographic examination of the facial, nasal and paranasal sinus regions of the horse. II. Radiological findings.

The radiographic findings in 167 horses subjected to radiography of the facial area, nasal cavity and paranasal sinuses are recorded. Cases were grouped according to clinical diagnosis and the common and disparate radiographic features between and within groups are discussed. Dental disease occurred most frequently and accounted for about 30 per cent of cases, most of which had periapical infection. This disorder presented as two distinct clinical entities in almost equal numbers affected teeth with roots rostral to the maxillary sinus usually produced facial swelling, whereas those with roots within the sinus were generally associated with nasal discharge as a result of secondary sinusitis. In the former group periapical changes could readily be identified on radiographs, but in the latter group affected teeth could be recognised with confidence in only about half the cases. Primary sinusitis was the commonest specific condition recorded and accounted for 32 cases, three of which were mycotic. Using lateral erect projections, comparison of the radiographic features of primary sinusitis and sinusitis secondary to dental disease showed some useful differentiating signs. In four ponies, rhinitis associated with sinusitis led to disruption of the intra-nasal structures but mycotic rhinitis, nasal ulceration and an intra-nasal foreign body produced no radiographic abnormalities. Sixteen cases of suture periostitis were recorded, with varying degrees of new bone formation, and of 13 animals presented for evaluation of trauma, pre-diagnosed fractures were demonstrated in 10 and complications due to sinusitis in three.(ABSTRACT TRUNCATED AT 250 WORDS)