Tracheal narrowing secondary to airway obstruction in two cats.

Tracheal narrowing is described in two cats. In both cases, inspiratory radiographs demonstrated tracheal narrowing just cranial to the thoracic inlet; no narrowing was seen on expiratory radiographs. Magnetic resonance imaging revealed suspected nasal tumours in both cases, but no abnormalities were identified in the region of the narrowed trachea. Nasal biopsy confirmed intranasal lymphoma in one cat and nasal adenocarcinoma in the other. The former cat was treated with chemotherapy. The owner of the latter cat declined further treatment. The tracheal narrowing disappeared after the initiation of chemotherapy in the cat with intranasal lymphoma and it is suggested that the narrowing might have been associated with the nasal tumour. A careful evaluation of the airway, especially cranial to the narrowing, is recommended in cases of tracheal narrowing in cats.