Radiopaque contrast dye in nasopharynx reaches the middle ear during swallowing and/or yawning.
CONCLUSIONS
Contrast dye in the nasopharynx reaches the middle ear during swallowing and yawning in normal adults. This suggests that displacement of bacteria in nasopharyngeal secretion to the middle ear may occur frequently during sleep.


OBJECTIVE
The middle ear is sterile under normal conditions. The purpose of this study was to examine by means of CT whether radiopaque contrast dye in the nasopharynx would reflux into the middle ear of normal adults during swallowing and/or yawning.


METHODS
Six normal adult volunteers were studied. Contrast dye was kept at the orifices of the Eustachian tube during swallowing and/or yawning by placing volunteers in either a head-down or lateral decubitus position. Reflux was determined by the presence of contrast dye in the middle ear on CT scanning of the temporal bone.


RESULTS
Two of the three volunteers in each group (four out of six in total) had contrast material detected in one or both middle ear cavities.
Winther
B
B
Department of Otolaryngology, Head and Neck Surgery, University of Virginia Health System, Charlottesville 22908, USA. bw8b@virginia.edu
Gwaltney
J M
JM
Phillips
C D
CD
Hendley
J O
JO
D000281:Administration, Intranasal; D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage / Q000493:pharmacokinetics*; D003679:Deglutition / Q000502:physiology*; D004432:Ear, Middle / Q000000981:diagnostic imaging / Q000378:metabolism*; D005064:Eustachian Tube / Q000378:metabolism; D005260:Female; D018475:Head-Down Tilt; D006801:Humans; D007472:Iohexol / Q000008:administration & dosage / Q000493:pharmacokinetics; D008297:Male; D008416:Mastoid / Q000000981:diagnostic imaging; D009305:Nasopharynx / Q000378:metabolism*; D011187:Posture; D013701:Temporal Bone / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed; D015000:Yawning / Q000502:physiology*
D003287:Contrast Media; D007472:Iohexol