ear anatomy
TRANSCRIPT
![Page 1: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/1.jpg)
Warm-up!!
![Page 2: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/2.jpg)
Anatomy and
Physiology of the
Ear
![Page 3: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/3.jpg)
3 Parts of the Ear
Outer, Middle, and Inner Ear
• Part 1 OUTER EAR- Pinna to Tympanic
Membrane
The “pre amp” –makes sound waves stronger
![Page 4: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/4.jpg)
Does Ear Wax Have a Purpose?
2 important functions
1.Keeps skin in ear canal
soft
2. Keeps bugs out
(they don’t like the taste)
![Page 5: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/5.jpg)
What Causes Outer Ear
Hearing Loss ?
• Wax pushed up against eardrum (tympanic membrane) from q-tip use
• Sharp objects that puncture tympanic membrane
• Born with damaged ear canal or without pinna
• Swimmer’s Ear - what is that?
![Page 6: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/6.jpg)
Swimmer’s Ear
• Water +
• Germs or bacteria +
• Wax in the auditory canal = mold
• Complications – temporary hearing loss, long-term infection, deep tissue infection, bone & cartilage damage, further infection
• How to treat it: antibiotics or antifungals, ear drops, steroids (for inflammation)
![Page 7: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/7.jpg)
Tympanic MembraneHealthy TM is translucent is
silvery in color
Red or pink or bulging shows
an infection.
![Page 8: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/8.jpg)
TYMPANIC MEMBRANCE
Normal versus Infection
![Page 9: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/9.jpg)
Part 2 - Middle Ear
• Sound waves change
to mechanical energy
in the middle ear
• ½” chamber
![Page 10: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/10.jpg)
What are the parts of the Middle
Ear?
• Back of tympanic membrane
• 3 small bones
• Eustachian tube
![Page 11: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/11.jpg)
Malleus, Incus, and Stapes
3 smallest bones in the body
![Page 12: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/12.jpg)
Eustachian Tube
• What is the
purpose?
• Drain cells/tissue
• Equalize air
pressure
![Page 13: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/13.jpg)
What Causes Hearing Loss in the
Middle Ear ?
• Calcium deposits on bones
Solution: surgery to remove the stapes bone
• Loud sudden noises- firecracker, gunshot
Solution?
• Trauma to the head- fall, car accident
• Otitis media – “middle ear infection”
![Page 14: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/14.jpg)
Otitis Media• Most common ailment
for children- Why???
• Germs travel up
eustachian tube-lodge in
middle ear
![Page 15: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/15.jpg)
Why are Parents concerned?
• Ossicles do not vibrate
correctly = 25dB hearing
loss
• Critical time for learning
language
• Treatments usually
include antibiotics and
occasionally ear drops.
• Sometimes repeated ear
infections can result in
tubes being put in ears.
![Page 16: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/16.jpg)
Ear Tubes- Chronic Otitis Media
Small slit made in TM and tube put
in for drainage from Middle Ear-
most tubes fall out after a few
months
![Page 17: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/17.jpg)
CONDUCTIVE HEARING LOSS
Any hearing loss occurring in the OUTER or MIDDLE EAR
• Malformed pinna
• too much wax
• swimmers ear (or water stuck in ear)
• torn tympanic membrane
• Otitis media
• calcium deposits on ossicles
• torn muscles that control the ossicles
Conductive Hearing Loss can be repaired
![Page 18: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/18.jpg)
The Inner Ear
• Cochlea
• semi- circular canals
• auditory nerve (8th
cranial nerve)
• Note the changes of
energy as the sound
waves come through
each part of the ear
![Page 19: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/19.jpg)
Entrance to the Inner ear
![Page 20: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/20.jpg)
The 3 bones vibrate causing a
disturbance at the “Oval Window”
![Page 21: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/21.jpg)
Parts of the Inner Ear
• Cochlea
• Semi-circular Canals
• Auditory (8th cranial) nerve
![Page 22: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/22.jpg)
Why do you get dizzy?
• Liquid in Semi –
Circular canals
• Information from
cilia sent to brain
• Must match info
sent from eyes
• Dizzy = brain doesn’t know what to follow
![Page 23: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/23.jpg)
The COCHLEA
• Size of a pea
• Fluid –filled
• Contains up to 20,000
cilia or hair-like nerve
endings
![Page 24: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/24.jpg)
• Movement of the fluid
stimulates the cilia
• Creates Electrical
impulses
![Page 25: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/25.jpg)
Auditory nerve- carries electrical
impulses from cilia (in cochlea and
semicircular canals) to the brain for
interpretation
![Page 26: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/26.jpg)
Sensorineural Hearing Loss
(Hearing loss in the Inner Ear)Known etiologies-
• Multiple Sclerosis
• Leukemia
• Sickle cell
• syphilis
• Bacterial infection( meningitis)
• Mumps
• ototoxic drugs (aspirin)
• tumor (from cell phones?)
• noise explosion
• menieres disease
• genetic connexin 26
• toys- noise levels
• membrane rupture
• airbag (ruptures tympanic membrane, tinnitus hearing loss)
• Premature birth
• unknown
![Page 27: Ear anatomy](https://reader033.vdocuments.mx/reader033/viewer/2022052912/55a0fa691a28ab96398b478e/html5/thumbnails/27.jpg)
Review--Pathway of Sound
• Sound waves enter pinna travel through auditory canal
• Sound waves strike tympanic membrane causing vibrations (mechanical energy)
• Vibrating TM causes ossicles to vibrate
• Vibrating stapes bone at oval window generates movement of cochlear fluid (Hydraulics)
• Fluid movement stimulates cilia- lined cochlea
• Cilia sends electrical impulses along auditory nerve to brain for interpretation