Magnetic resonance imaging for the assessment of lingual thyroid.

A 43-year-old woman was evaluated because of a round tumor at the base of the tongue. Scintigraphy with 131I showed radionuclide uptake over the posterior part of the tongue but no uptake at all at the usual pretracheal location. Magnetic resonance imaging revealed a well defined round mass of high signal intensity, which was clearly delineated from adjacent muscular tissue.