Blue boxes: Ear anatomy

Question 1

Describe an auricular hematoma

Answer 1

Localized collection of blood that forms between the perichondrium and the auricular cartilage, that causes distortion of the contours of the auricle; if this enlarges, there will be compression of the blood supply to the cartilage

Can result in fibrosis of the ear (cauliflower ear) which can cause a deformed auricle

Question 2

Describe acute otitis externally

Answer 2

Inflammation of the external auditory canal (swimmers ear) can be the result of a bacterial infection

pulling on the ear or the tragus typically causes an increase in pain

Question 3

Describe otitis media

Answer 3

earache secondary to the bulging of the TM secondary to pus or fluid behind the ear which can cause blockage of the ET

if untreated can lead to hearing deficits

Question 4

Describe perforation of the TM

Answer 4

A hole in the TM that can be caused by

1. otitis media
2. Perforation from foreign bodies

Question 5

Where are the incisions from a middle ear abscess typically made and why?

Answer 5

Incisions are made postero-inferiorly through the membrane; they are made here because the inferior portion of the TM is less vascularized

This also avoids the ossicles and damage to the chordates tympani

Question 6

Why are tubes placed in little kids?

Answer 6

Because of recurrent middle ear infections or abnormal drawing of the Eustachian tubes

Question 7

Describe mastoiditis

Answer 7

Inflammation of the mastoid cells secondary to infection that can spread to the middle cranial fossa and cause osteomyelitis

Question 8

Describe blockage of the pharyngotympanic tube

Answer 8

Causes retraction of the TM because of the blockage of the tube causing a negative pressure on the TM and affecting hearing

Question 9

Describe paralysis of the stapedius

Answer 9

(Lesion of CN VII) excessive acuteness of hearing

Question 10

Describe motion sickness

Answer 10

Results from discordance between the vestibular and visual stimulation secondary to the otoliths of the hair cells responding the linear acceleration and deceleration and causing proprioceptive changes

Question 11

What are the three major symptoms that are caused by an injury to the peripheral auditory system?

Answer 11

1. Hearing loss
2. Vertigo
3. Tinnitus (ringing)

Question 12

What is conductive hearing loss?

Answer 12

Anything in the external or the middle ear that interferes with the conduction of sound or movement of the oval or round windows

patients will speak softly because their voices sound louder than everyone else’s voices

can be improved with a hearing device

Question 13

What is sensorineural hearing loss?

Answer 13

defects in the pathway from the cochlea to the brain; affecting the middle ear

cochlear implants can be placed to transmit the impulses from the sound to the cochlea and stimulate the cochlear nerve

Question 14

Describe Meniere syndrome

Answer 14

Excess endolymph production that is caused by the blockage of the endolymphatic duct that causes tinnitus, hearing loss, and vertigo

sense of pressure in the ear, distortion of sounds, and sensitivity to noises

Question 15

What is a characteristic sign of Meniere syndrome?

Answer 15

Balooning of the cochlear duct, utricle, saccule, and in increase in the endolymphatic volume

Question 16

What is high tone deafness?

Answer 16

Persistent exposure to loud sounds can cause degeneration of the spiral organ

Question 17

What is otic barotrauma?

Answer 17

Caused by an imbalance in the pressure between the ambient air and the air in the middle ear

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