disorders affecting the OUTER EAR Flashcards
what is the average size of the adult ear?
The average adult ear is ~ 2.5 cm (1 inch) long and ~ 0.7 cm (0.3 inches) in diameter
what are the 2 branches the pinna is supplied by?
by two branches of the external carotid artery with an extensive network of connections between the two branches, which are the:
1)Superficial temporal artery
2) Postauricular artery
where does the venous drainage end?
Venous drainage ends in the external and internal jugular veins
what sensory innervation is in the pinna
1) by various cervical spinal nerves ->(lesser occipital nerve)
2) branches of the trigeminal nerve ->(auriculotemporal)
3) vagus nerve-> (auricular branch)
why is it hard to reconstruct the pinna?
because of the intricate and delicate topography and blood supply makes reconstruction of the auricle difficult
can genetic factor affect the pinna?
yes!
can genetic disorders of the pinna be recessive or dominant?
both!
can the outer ear indicate middle and inner ear abnormalities ?
-Some auricular deformities may be an indication of middle and inner ear abnormalities, which may cause hearing loss or deafness
For this reason, it is good practice to inspection the outer ear during otoscopy
correlations with auricle anomality’s can indicate type of problems with what body part?
Children with auricular anomalies show a slightly increased risk of concurrent renal abnormalities, which may require medical/surgical intervention
what is mircotia?
The term describes underdevelopment of the outer ear
what is the range of microtia ?
Represents a range of findings from complete agenesis (absence of pinna) to somewhat small ears with atretic canals
what does microtia look like?
The most common finding is a sausage-like or “peanut” ear
who is more likely to get microtia between men or females ?
Twice as many males as females affected
is the right ear or left ear typically seen to get microtia ?
The right ear is most often involved, and it is rarely bilateral
what is atresia ?
no opening of the ear canal
where is bilateral mircotia seen?
it’s frequently seen with patients who have treacher collins (at arch) syndrome)
what is a constricted ear?
The helix kind of enlarges
The encircling helix is tight
what is included in a constricted ear?
loop ear and a cup ear
what is a loop ear?
This is where the helix kind of buldges up
an inferior bending of the superior helix
what is a cup ear?
an increase in the bowl size
what is auricular appendages ?
Common anomaly, often a result of accessory auricular hillocks from which the auricle develops
are auricular appendages unilateral or bilateral?
Usually, unilateral
what is typically involved in auricular appendages?
May contain skin alone or skin and cartilage
can HL be seen in auricular appendages ?
May present with associated hearing loss
A complete audiologic evaluation is necessary
what is auricular sinuses/pits?
Usually harmless, pit-like depression anterior to the auricle
what might cause auricular sinuses /its?
May be a result of failed closure of part of the first branchial groove
can auricular sinuses/pit be blocked with stuff?
May become blocked with debris or secondarily infected
auricular trauma can be a result of ?
Thermal injury (burns or frostbite)
Penetrating injury
Blunt injury
why is the auricle susceptible to trauma?
Because of its prominent, and unprotected position, they’re just out there
what are treatments for auricular trauma?
Auricular trauma often requires antibiotics and tetanus prophylaxis but may also require surgical reconstruction
what is an auricular hemotoma?
-blood vessels separate under the cartilage
-Can occur as a result of blunt force trauma and contact sport
-Blood vessels in the perichondrium (membrane covering the cartilage of the outer ear) get separated from the underlying cartilage
what happens when cartilage receives oxygen and nutrients in auricular hematoma?
it results into scarring
Because the cartilage receives oxygen and nutrients from the perichondrium, the separation can result in devitalization of the avascular cartilage and subsequent fibrosis (scarring)
what happens if the hematoma is left untreated?
cauliflower
If the hematoma is left untreated, new and asymmetric cartilage forms from the perichondrium resulting in a distorted/thickened external ear or CAULIFLOWER EAR!!!
where is auricular hemotoma typlically seen?
commonly seen in wrestlers, boxers and football players
where are penetrating injuries seen?
Seen with knife wounds, human and animal bites, and motor vehicle accidents
what can result from penetrating injuries ?
Can result in complete or partial avulsion (separation) of the auricle
can penetrating injuries be reattached?
-Re-attachment is possible and often successful if done relatively early, preferably within five hours of the injury
-If the ear is completely torn off, it should be transported in a cold, sterile container for re-attachment
what is penetrating injuries ?
they’re blunt force trauma
what is perichondrits ?
Inflammation of the perichondrium and cartilaginous layer can be categorized as
Infectious or suppurative perichondritis
Noninfectious termed relapsing perichondritis
why is perichondritis considered a misnomer?
The term perichondritis is a misnomer because
cartilage is almost always involved in
treatment in auricular hemotona, for both humans and animals, in terms of bites?
prophylatic tetanus and antibiotics is mandatory
thermal injuries are due to?
frost bite and burns
why is important to protect the skin in a thermal injury?
because there is no protective layer of skin so it’s a bigger risk of infection
the bigger the burn the more risk the infection
what is perichondritis pt2
inflammation of the cartilage due to frost bite or bug bite or piercing but either way there is puss
what causes perichondritis ?
Injury, burns, insect bites, ear piercing, boils, etc.
perichondritis has an insidious (slowly might note notice right away) onset of?
-Initially presenting with a dull ache, warmth, and redness
-If untreated, it can progress to cartilaginous necrosis and deformity
can an infection of the auricle be bacterial or viral?
Infections of the auricle can be bacterial or viral
what is the most common VIRAL infection that goes with CN 7?
The most common viral infection with accompanying VII N paralysis is herpes zoster oticus (shingles) or Ramsay Hunt Syndrome
what is shingles or ramsay hunt syndrome caused by ?
Caused by reactivation of latent varicella zoster (chicken pox) virus in geniculate, spiral, and vestibular ganglion, and VII nerve sheath
what is shingles or ramsay hunt syndrome ranked on facial nerve palsy?
The 2nd most common cause of facial nerve palsy (3 to 20%)
what is the earliest symptom seen in shingles or ramsay hunt syndrome?
-The earliest symptom is pain and painful rash in the ear canal, concha, or below/behind the auricle
-The rash is caused by the virus localizing in the skin and resulting in painful vesicular (blister) eruptions
what other cn can be involved in infections of the auricle?
Other cranial nerves involved including VIII N; hearing loss & vertigo
what is the medical intervention of an infected auricle?
-Clinical symptoms begin to resolve within 12 to 14 days
-Medical intervention is required, typically with antiviral drugs & steroids
in infected auricle, what is affected?
just the skin! not the auditory system
what is allergic contact dermatitis caused by?
Caused by exposure to medicinal and cosmetic products (particularly jewelry containing nickel)
-it can happen to anywhere on the body
what is it called when the auricle has an allergic reaction?
when the auricle is prone to allergies, what can be a result form this?
The auricle is prone to allergies resulting most commonly in contact dermatitis
how does the auricle look like in allergic contact dermatitis ?
The auricle becomes red, inflamed, and there may be pain
what is treatment for allergic contact dermatitis ?
Topical antibiotics and steroids
what is seborrheic dermatitis caused by ?
believed to be due to infection by a yeast-like organism, Malassezia furfur ( yeast)
but it’s not really known
what is Seborrheic dermatitis?
skin inflammation
what can result from Seborrheic dermatitis?
-Results in scaly superficial eczematous dermatitis (not contagious)
-which then Often causes otitis externa
what is the treatment of Seborrheic dermatitis?
Decrease yeast colonization and inflammation by antimycotic drugs, topical steroid cream, and drops
-antibiotics because its fungal
what does neoplasm mean?
new tissue
-itcan be either benign or malignant
what do benign neoplasm include what ?
Benign neoplasms include cysts and keloids
(keloids are scar tissue)
what are sebaceous cysts?
Fluid filled cysts
that are generally seen following trauma such as ear piercing
-they can be secondary infection
what is the treatment of sebaceous cyst ?
antibiotics and then surgical excision
what are keloids?
Benign outward overgrowth of scar tissue
where are keloids seen?
Commonly seen following ear trauma, ear piercing, and viral infections like herpes varicella zoster
can keloids spread?
Keloids can spread to adjacent tissue
what is the treatment of the keloid ?
Surgical excision
Steroid injections
what is malignant neoplasm?
skin cancer? but they’re rare