Middle-ear pressure and eustachian tube function.
In 92 healthy persons with the common cold, 184 ears were examined and 786 coincidental sonotubometric and tympanometric measurements were taken. There was a good tubal function when the middle-ear pressure was 0 to -25 mm H2O, with 91% of the tubes opening during swallowing. A systematically reduced tubal opening was noted as the middle ear pressure decreased from 0 to -200 mm H2O. The present study discloses that a negative middle-ear pressure evaluated by tympanometry does not always denote a closed tube, nor does a flat tympanogram necessarily indicate a middle-ear effusion. No definite limits could be ascertained for the normal middle-ear pressure; the middle ear is extremely dynamic, and middle-ear pressure can change for many reasons.
D000158:Acoustic Impedance Tests; D000328:Adult; D001298:Audiology / Q000379:methods; D003139:Common Cold / Q000503:physiopathology; D004432:Ear, Middle / Q000502:physiology / Q000503:physiopathology*; D005064:Eustachian Tube / Q000502:physiology / Q000503:physiopathology*; D006801:Humans; D008875:Middle Aged; D011312:Pressure; D012016:Reference Values