Tympanic membrane retraction used to manage tympanic membrane retraction, with the aims of preventing or relieving hearing loss and cholesteatoma formation. As retraction pockets may remain stable or resolve spontaneously, it may be appropriate to observe them for a period of time before considering any active treatment. The Valsalva maneuver increases middle ear pressure and can push a retracted eardrum out of the middle ear if is not adherent to middle ear structures. Hearing may improve as a result, however it can be a painful maneuver. The benefits are typically only temporary. Middle ear pressure can also be increased by Politzerization and with
Dirac membrane Dirac membrane A model of a charged membrane introduced by Paul Dirac in 1962. Dirac's original motivation was to explain the mass of the muon as an excitation of the ground state corresponding to an electron. Anticipating the birth of string theory by almost a decade, he was the first to introduce what is now called a type of Nambu–Goto action for membranes. In the Dirac membrane model the repulsive electromagnetic forces on the membrane are balanced by the contracting ones coming from the positive tension. In the case of the spherical membrane, classical equations of motion imply that the