ear stuff 2 Flashcards
Congenital Aural atresia is
- spectrum of disorders present from birth
2. malformations of external auditory canal, TM, middle ear space or ossicles
congenital aural atresia treatment
surgery
meniere’s disease signs
- vertigo lasting more than 20 minutes
- hearing loss
- tinnitus
- aural fullness
- chronic disease
- fluctuating hearing loss
Meniere’s disease is
- swelling of endolymphatic space from a problem of stria vascularis
- loss of endocochlear potential due to poor ion conduction
Meniere’s disease treatment
- diuretic for swelling
- Mg for vertigo
- surgery if non-responsive
- injection of gentamicin into canals
8th nerve tumor is a
vestibular schwannoma
vestibular schwannoma early signs
- hearing loss
- tinnitus (unilateral)
- mild/fleeting vertigo
vestibular schwannoma late signs
- facial numbness
- ataxia
- headache
- visual loss
- long tract signs
4 death by herniation
vestibular schwannoma two forms
- NF2
2. sporadic form
NF2
- NF2 is a tumor suppressor gene that codes for merlin
2. merlin involved in cell-cell or cell-matric interaction
Sporadic vestibular schwannoma is
possible double hit mutation to merlin
vestibular schwannoma treatment
- watchful waiting to see if tumor grows
- surgical resection
- radiosurgery or radiotherapy
sensory hearing loss us usually due to
loss of hair cells or impaired inner ear homeostasis
hair cell loss is commonly due to
- prebycusis
- noise trauma
- ototoxicity
- genetics
damage to outer or inner hair cells can result in
irregularity in the pattern or loss of architecture of individual hair cells .
Without hair cells, mechanical sound waves are unable to be transduced to electrical signals for the nervous system
sensory loss can also be due to
improper inner ear homeostasis.
Like in endolymphatic hydrops
etiology of endolymphatic hydrops
- stria vascularis, the structure on the lateral edge of the scala media. Is responsible for maintaining homeostasis of inner ear
- creates and maintains the endolymphatic potential
etiology of meniere’s disease
- potential not maintained properly
- results in disruption of ion transport, changes in ph, and changes in osmotic pressure of scala media.
- changes ultimately cause fluid to enter and swelling of endolymphatic space.