Pressures of the porcine tympanic membrane

The mean rupture pressure of the porcine tympanic membrane (TM) was measured in 9 specimens. Pressure was delivered gradually into the external ear canal of an excised piece of temporal bone, via a syringe and polyurethane tubing attached to the canal. Tympanometry was used to ascertain the structural integrity of the TM before pressure delivery. Rupture pressure was defined to be that point at which a sudden drop occurred in the overpressure in the ear canal, as measured by a pressure gauge. From the results, we concluded that the mean rupture pressure for the porcine TM is 1.2 +/- 0.3 atm. This is of the same order of magnitude as and slightly less than pressures obtained for the human TM.