Arterial Anomalies of the Middle Ear: A Pictorial Review with Clinical-Embryologic and Imaging Correlation.

The differential diagnosis of a red and/or pulsatile retrotympanic mass includes aberrant internal carotid artery, persistent stapedial artery (PSA), glomus tympanicum, and dehiscent jugular bulb. By recognizing the features of aberrant internal carotid artery and PSA on high-resolution computed tomography, these entities can be assessed by the radiologist. PSA is further classified by type because each type demonstrates a unique set of imaging features in addition to features common to all types. Although rarely encountered, it is important to reliably and consistently detect these anomalies because failure to do so can lead to disastrous surgical outcomes.