Vidian nerve and the eustachian tube.

The vidian nerve was stimulated electrically in the dog and this resulted in a reduced patency of the Eustachian tube. The effect was atropine resistant. This physiological evidence in the dog corresponds to anatomical evidence in man of a parasympathetic, vasodilator nerve bundle passing through the vidian to the sphenopalatine ganglion and then via the pharyngeal nerve to the Eustachian tube mucosa. Additional parasympathetic routes to the tube may exist.