Otology A2


Middle ear anatomy

A number of nerves pass through the middle ear, the most important of which is the facial nerve, which passes through the facial canal as it courses out from the internal auditory meatus. The facial nerve gives off the chorda tympani nerve (supplying taste to the anterior tongue) along with a nerve to stapedius, the smaller of two muscles located in the middle ear. The stapedius muscle acts on the stapes to stabilise it and prevent excessive oscillation. 

The other muscle, tensor tympani, acts on the handle of malleus, tensing the tympanic membrane and thus reducing transmitted sound vibrations; it is innervated by a branch of the mandibular division of the trigeminal nerve. Other nerves related to the middle ear include a branch of the glossopharyngeal nerve (tympanic nerve).

Correct Answer: