Ear Anatomy

  1. Auricle
    Blood supply?
    Innervation?
    • Auric)le
    • Blood supply: Post. Auricular A.
    • Innervation:
    • Post. Auricular n. (CN VII - motor)
    • Lesser Occipital & Greater Auricular n. (sensory)
  2. External Acoustic Meatus
    Blood Supply
    Innervation
    • External Acoustic Meatus
    • Blood Supply: Post. auricular, maxillary, superficial temporal (AMT)
    • Innervation:
    • Auriculotemporal (CN V3)
    • Auricular br. CN IX & X(Arnold n.)
    • Facial n.
  3. Middle ear (tympanic membrane) boundaries?
    Roof
    tegmen tympani
  4. Middle ear (tympanic membrane) boundaries?
    Floor
    jugular foramen w/IJV posteriorly & ICA anteriorly
  5. Middle ear (tympanic membrane) boundaries?
    Lateral & Medial Wall
    • Lateral:
    • tympanic membrane
    • malleus-umbo
    • pars flacida (malleolar folds)

    • Medial:
    • promontory w/tympanic plexus
    • fenestra vestibuli (OW)
    • fenestra cochlea (RW)
  6. Middle ear (tympanic membrane) boundaries?
    Posterior & Anterior Walls
    • Posterior:
    • mastoid antrum
    • stapedius m.
    • facial canal


    • Anterior:
    • canal for tensor tympani & PT tube
    • ICA
  7. Middle ear (tympanic cavity) contents?
    Nerves
    • chorda tympani (CN VII)
    • tympanic br. of IX
    • tympanic plexus (greater petrosal - lacrimal & lesser petrosal - parotid)
  8. Middle ear (tympanic cavity) contents?
    Arteries & Veins
    • Ateries
    • maxillary a.
    • middle meningeal
    • vidian a. - pterygoid canal a.
    • ascending pharyngeal a.
    • ICA

    Veins: Pterygoid venous plexus --> cavernous sinus
  9. Middle ear (tympanic cavity) contents?
    Lymphatics
    deep cervical LN
  10. Middle ear (tympanic cavity) contents?
    Muscles
    • Tensor tympani - CN V3
    • Stapedius - CN VII
    • auditory reflex: contract w/loud sounds
  11. Otitis media
    infection of cavity from nasopharynx
  12. Hyperacusis
    paralysis of stapedius (CN VII)
  13. Hypoacusis
    paralysis of tensor tympani (CN V3)
  14. Weber Test
    • normal: no lateralization
    • conductive deafness: hear louder on affected side
    • sensorineural deafness: hear louder on unaffected side
  15. Rinne's Test
    • normal: BC=AC
    • conductive deafness: BC > AC
    • sensorineural deafness: AC > BC
  16. Auditory Reflex
    axons from Sup. Olivary N. terminate in Trigeminal & Facial motor nuclei

    • stapedius - VII
    • tensor tympani - V3
Author
catitasilva
ID
122524
Card Set
Ear Anatomy
Description
Ear anatomy
Updated