Sonographic findings in glomus tympanicum tumor.

A glomus tympanicum tumor that is associated with a visible retrotympanic mass is the most frequent cause of pulsatile tinnitus. The preoperative diagnostic approach to this lesion includes a meticulous physical examination as well as high-resolution CT, magnetic resonance angiography, and digital angiography, which can also be used for preoperative embolization. We report the use of color transcranial Doppler sonography in the evaluation of glomus tympanicum tumor in a 67-year-old woman with a 3-year history of left tinnitus. An otoscopic examination revealed a reddish pulsatile mass behind an intact tympanic membrane. No lesions were visualized on gray-scale sonography. Contrast-enhanced color transcranial Doppler sonography showed a vascular ovoid mass that measured 2 x 1 x 1 cm; spectral analysis of the lesion revealed arterial flow with a low resistance index. Color transcranial Doppler sonography helped define the dimensions and vascular characteristics of the lesion.