Pseudotumours of the oropharynx due to muscular contraction.

Normal filling defects in the barium-filled oropharynx are described. These pseudotumours result from the contraction, elevation and backward pulling of the soft palate assisted by the rounded ridge (of Passavant) in the pharyngeal wall produced by contraction of the palatopharyngeal sphincter, and the action of the palatopharyngei during swallowing. Other anatomical explanations for these filling defects are mentioned. The importance of recognising the changing pattern of these defects as being normal, and their differentiation from space occupying lesions in the oropharynx is emphasised.