CT and MRI evaluation of skull bones and soft tissues in six cats with presumed acromegaly versus 12 unaffected cats.

Feline acromegaly is predominantly caused by an adenoma of the pituitary gland, resulting in excessive growth hormone and insulin-like growth factor (IGF-1) secretion. In advanced cases, cats will display prominent facial features and upper airway congestion secondary to bony and soft tissue proliferation. The purpose of this study was to describe CT and MRI characteristics of soft tissues and skull bones in six cats with presumed acromegaly and to compare findings with those observed in 12 unaffected cats. In the five acromegalic cats with CT or MRI evidence of a pituitary tumor, frontal bone thickness was greater than age-matched controls with and without a history of upper airway disease. These five cats also had evidence of soft tissue accumulation in the nasal cavity, sinuses, and pharynx. One cat with insulin-resistant diabetes mellitus, elevated IGF-1, and a normal pituitary size did not have evidence of frontal bone thickening or upper airway congestion.