Ear - 4/6 Stephens Flashcards
Where does bone conduction occur?
Fluid conduction?
Ossicles of middle ear
Inner ear
Trauma to what region of the ear will result in an auricular hematoma?
Pinna
What is the blood supply to the auricle of the ear?
Superficial temporal a.
Posterior auricular a.
The outer epidermis of the tympanic membrane is innervated by what nerve(s)?
What type of fibers?
CN 5 and 10
GSA
What does the middle fibrous layer of the tympanic membrane form?
Pars tense
Pars flaccida in the antero-superior quadrant
Fibrous layer
What innervates the inner mucous membrane of the tympanic membrane?
What type of fibers?
CN 9 via the tympanic plexus
GVA
What is otitis media?
Common in who?
Inflammation of the middle ear cavity in infants and children
More common in infants bc auditory tubes oriented horizontally
Fractures of what bone may cause otorrhea, otorrhagia, vestibular disturbances, deafness, or Bell’s Palsy?
Petrous temporal bone
What nerve cross the neck of the malleus?
Chorda tympani
Action of tensor tympani muscle?
Innervation?
Tightens the tympanic membrane and attenuates vibrations
V3
Stapedius muscle action?
Innervation?
Attenuates sound
CN 7
Lesions in the greater petrosal nerve result in what?
Absence of lacrimation in the ipsilateral eye
Lesions in the stapedius muscle result in what?
Hyperacusis
Lesions of chorda tympani result in what?
Loss of taste anterior 2/3 of the tongue
Decreased salivation from the submandibular and sublingual glands
Lesion of nerve to posterior digastric results in what?
Lower jaw deviating towards the normal side when mouth is wide open
