Eustachian tube patency detected by a photoelectric method.

A method was developed to observe tubal orifice movement by fiberscope and detect patency of the eustachian tube by a photoelectric device (phototubometry). A highly sensitive photodiode in the external ear canal detected tube opening as increased luminosity in the tympanic cavity from a light source placed at the pharyngeal portion of the eustachian tube. The phototubometric record was superimposed on a TV screen to compare the opening in the pharyngeal portion of the eustachian tube to the tube opening during swallowing. The phototubometric records of 21 normal subjects examined by phototubometry showed the close relationship with the opened tubal lumen at the tensor veli palatini muscle (TVP) attached portion. This method is useful for examining tubal patency and observing changes in the pharyngeal portion of the eustachian tube.