Hearing Loss Flashcards
How common is hearing loss in newborns?
1/1000 = born profoundly deaf
2-3/1000 = born w less severe HL
Out of non-syndromic cases of hearing loss, what % is caused by Connexin mut?
50%
(1/3 = syndromic; 2/3 = non-synd)
What type of hearing loss results from a difference between the air conduction and bone conduction?
conductive hearing loss —> meaning something is preventing the sound wave from entering the inner ear
What type of hearing loss results from decreased hearing level in dB as freq increases?
sensorineural
The eardrum is attached to ?
malleus –> incus –> stapes
Conductive hearing loss stops at the ? part of the ear
cochlea (so like it is NOT going to brain)
something stopping sound from going to inner ear
Can a typical ear exam show us problems arising in cochlea?
nope - will look normal
cannot detect sensorineural on typ exam
What ype of infectiosn can cause hearin gloss?
- CMV (biggest one)
- TORCH
- Zika
- Measles/Mumps
- Meningitis –> rare, but results in profound HL and ears ossify over time and fill up w tissue and bone
Why would we do EKG for hearing loss?
Look out for Jervell-Lange-Nielson
When do you ned to make a CMV dx to determ if congenital?
1st 3w of life
Cochelar implants allow sound transmission from where to where?
transmits sound directly to the auditory nerve through direct electrical stim of the cochlea
What type of hearing loss do we see in CHARGE?
(CHD7)
they usu have ear abnorm + sensorineural hearing loss (>90%)
they usu qualify for cochlear implants
What is one of the most common mut assoc w hearing loss?
GJB2
can account for up to 50% hearing loss in W Euro pop
What are next steps if we find 2 mut in USH2A
this is AR, so need to test parents to see phasing
HL is mild to severe - mainly affects high tones
follow up w Opthal bc RP as one ages
unlike other forms of Usher syn, NOT see diff w balance
Jervell and Lange-Nielson syndrome is caused by?
KCNE1 or
KCNQ1 (90%)
- code for channel proteins that move K+ in the inner ear + cardiac muscles
(AR)
