Ear Flashcards
NS to upper 2/3 of lateral pinna
Auriculotemporal
NS to lower 1/3 of lateral pinna
Great auricular
NS of upper 2/3 of medial pinna
Lesser occipital
NS to lower 1/3 of medial pinna
Great auricular
NS to root of auricle
Auricular branch of vagus
BS to auricle
Posterior auricular
Superficial temporal
Lymphatic drainage of auricle
Preauricular
Postauricular
BS of external acoustic meatus
Outer - superficial temporal, posterior auricular
Inner - deep auricular branch of maxillary
NS of external acoustic meatus
Ant. - auriculotemporal
Post. - auricular branch of vagus
BS of tympanic membrane
O- deep auricular of maxillary
I- anterior tympanic branch of maxillary
Posterior tympanic of stylomastoid of posterior auricular
Venous drainage of tympanic membrane
O- external jugular vein
I- transverse sinus
Lymphatic drainage of tympanic membrane
Preauricular
Retropharyngeal
NS of tympanic membrane
O- auriculotemporal + auricular branch of vagus
I- tympanic branch of glossopharyngeal
Roof of middle ear
Tegmen tympani
Floor of middle ear
Temporal bone
Anterior wall of middle ear
- Canal for tensor tympani
- Opening of auditory tube
- Posterior wall of carotid canal perforated by A).superior and inferior sympathetic caroticotympanic nerves and B).tympanic branch of internal carotid artery
- Bony part between canals is continued as processus cochleariformis which reaches upper part of malleus
Posterior wall of middle ear
- Opening of aditus through which epitympanic recess connects with mastoid antrum
- Fossa incudis
- Pyramidal projection has a passage for tendon of stapedius
- Posterior canaliculus for chorda tympani nerve
Lateral wall of middle ear
- Tympanic membrane
- Squamous temporal bone
- Petrotympanic fissure lodges anterior process of malleus and transmits tympanic branch of maxillary artery
- Anterior canaliculus for chorda tympani
Medial wall of middle ear
- Promontory - bulge by first turn of cochlea grooved by tympanic plexus
- Round window
- Oval window
- Prominence of facial canal
- Prominence of lateral semicircular canal
Contents of middle ear
- Ear ossicles
- Joints b/w ear ossicles
- Tensor tympani and stapedius
- Vessels
- Chorda tympani and tympanic plexus
Malleus
- Head in epitympanic recess, articulates with body of incus
- Neck- against pars flaccida related to chorda tympani
- Anterior process - to petrotympanic fissure by anterior ligament
- Lateral process
- Handle attached to tympanic membrane
Incus
- Large body - articulates with head of malleus
2. Long process - articulates with head of stapes
Stapes
- Small head - articulates with incus
- Narrow neck - provides insertion to stapedius
- Two limbs/crura - attached to footplate
- Footplate - oval, fits into oval window
Joints of middle ear
- Incudomalleolar joint - saddle joint
2. Incudostapedial joint - ball and socket
Tensor tympani
- lies in bony canal above auditory tube
- muscle arises from walls of canal
- tendon reaches medial wall of middle ear,
- bends around processus cochleariformis.
- inserts into handle of malleus
- supplied by mandibular nerve
Stapedius
- lies in bony canal related to posterior wall of middle ear.
- this canal is continuous with canal for facial nerve
- canal opens into summit of pyramid
- supplied by facial nerve
Arterial supply of middle ear
- Anterior tympanic branch of maxillary A.
- Posterior tympanic branch of posterior auricular A.
- Petrosal and superior tympanic branch of middle meningeal A.
- Ascending pharyngeal A.
- Tympanic branches of internal carotid A.
Venous drainage of middle ear
Superior petrosal sinus
Pterygoid venous plexus
Lymphatic drainage of middle ear
Preauricular
Retropharyngeal
Nerve supply of middle ear
- Tympanic branch of glossopharyngeal nerve
2. Superior and inferior caroticotympanic nerves
