IN TYMPANOPLASTY, it is sometimes necessary to deal with absence of the malleus head in conjunction with other ossicle defects, especially following cholesteatoma in the attic. It may also be necessary in some cases to remove a malleus head which has become fixated to the epitympanic wall. These conditions raise the question of whether absence of the malleus head limits the degree of hearing restoration which may be expected from tympanoplasty.
The available literature would suggest that this might be so. Bekesy1 has described the counterbalance function of the malleus head and the way in which the absence of this structure upsets the coincidence of the center of gravity and the axis of rotation of the ossicle chain, causing stress on the eardrum which interferes with its normal mode of vibration. A quantified estimate of the effect of this interference has been reported by Lawrence,2 who measured
ELPERN BS, ELBROND O. Acoustic Effects of Removing the Malleus Head. Arch Otolaryngol. 1966;84(2):170–172. doi:10.1001/archotol.1966.00760030172010
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