Computed tomography of the tongue in primary amyloidosis.

Primary amyloidosis is a systemic disease that may cause diffuse enlargement of the tongue or macroglossia. Obvious macroglossia is easily detected by clinical inspection. There is no agreement, however, on an objective measure of tongue enlargement. Computed tomography of the base of the tongue was performed in 12 patients with primary amyloidosis. Tongue width and width of the hyoglossus and genioglossus muscles were measured. Based on normal measurements it was concluded that macroglossia is present if the tongue is wider than 50 mm and the genioglossus wider than 11 mm. This should be accompanied by a midline cleft of the tongue surface and outward displacement of normal-size submandibular glands.