Disorders Affecting the Outer Ear Flashcards
How big is an average adult ear?
2.5 cm (1 in) long and 0.7 cm (0.3 in) in diameter
What is the blood supply of the pinna?
Two branches of the external carotid artery
Superficial temporal artery and postauricular artery
Where does the venous drainage for the pinna end?
In the external and internal jugular veins
What are the sensory innervations of the pinna?
Various cervical spinal nerves, branches of the trigeminal nerve, and vagus nerve
A lot of innervations
What makes reconstruction of the pinna difficult?
Intricate and delicate topography and blood supply
Can genetics be a factor in specific auricular deformities?
Yes
What kind of transmission does auricular abnormalities have?
AD or AR
Can auricular deformities be an indication of middle and inner ear abnomalities?
Yes
These may lead to hearing loss or deafness
Good to practice inspection of the outer ear during otoscopy
Can children with auricular abnormalities show a slightly increased risk of concurrent renal abnormalities?
Yes
May require medical/surgical intervention
What is microtia?
Underdeveloped outer ear
Range from agenesis (absence of pinna) to somewhat small ears with atretic canals
Twice as many males affected
The right ear is most often involved
Rarely bilateral
What is the most common finding of microtia?
Sausage like or peanut ear
What is a constricted ear?
The encircling helix is tight
Purely cosmetic
Loop ear and cup ear
What is a loop ear?
An inferior bending of the superior helix
What is a cup ear?
An increase in bowl size
Is each ear unique?
Yes
No two people share the same pinna shape and form
What are auricular appendages?
Like skin tags
Common anomaly
Usually unilateral
May contain skin alone or skin and cartilage
What are auricular appendages often caused from?
Resulting from accessory auricular hillocks from which the pinna develops
Can auricular appendages present with associated hearing loss?
Yes
A complete audiologic evaluation is necessary
What are auricular sinuses/pits?
Usually harmless
Pit-like depression anterior to the pinna
May become blocked with debris or secondarily infected
What might auricular pits result from?
Failed closure of part of the first branchial groove
What can auricular trauma result from?
Thermal injury (burns or frost bite)
Penetrating injury
Blunt injury
Is the pinna susceptible to trauma?
Yes
It is prominent and unprotected
Unlike the eye, it has no protective reflex
What does auricular trauma require?
Antibiotics and tetanus prophylaxis
Sometimes surgical reconstruction
How can auricular hemotomas occur?
Blunt force trauma and contact sports
Who are auricular hemotomas commonly seen in?
Wrestlers, boxers, and football players
What happens in auricular hemotomas?
Blood vessels of the perichondrium (membrane covering the cartilage of the outer ear) gets separated from the underlying cartilage
This separation can result in devitalization of the avascular cartilage and subsequent fibrosis (scarring)
What happens if an auricular hemotoma is untreated?
New and symmetric cartilage forms from the perichondrium
Distorted and thickened external ear
Cauliflower ear
What are penetrating injuries?
Blunt force trauma
Knife wounds, human and animal bites, and motor vehicle accidents
Can penetrating injuries result in complete or partial separation of the pinna?
Yes
Is reattachment of the ear possible?
Yes, early on
Preferably within 5 hours
Might never be normal, but they have better success
If the ear is completely torn off, should it be transported in a cold, sterile container?
Yes
What should be done after a human or animal bite?
Prophylactic tetanus and antibiotics
What is perichondritis?
Inflammation of the perichondrium and cartilaginous layer
What are the two categories of perichondritis?
Infectious or suppurative
Noninfectious or relapsing
Is cartilage usually involved in cases of perichondritis?
Yes
What is perichondritis caused by?
Injury, burns, insect bites, ear piercings, boils, etc.
Does perichondritis have an insidious onset?
Yes, it happens slowly and you might not notice
Initially presenting with a dull ache, warmth, and redness
If perichondritis is untreated, what can it progress to?
Cartilaginous necrosis and deformity
Infection of the auricle
What is allergic contact dermatitis?
Caused by exposure to medicinal and cosmetic products
Jewelry containing nickel
Pinna becomes red, inflamed, and there may be pain
What is the treatment for allergic contact dermatitis?
Topical antibiotics and steroids
Can infections of the pinna be both bacterial and viral?
Yes
What is the most common viral infection?
Accompanying VII N paralysis
Herpes zoster oticus (shingles) or Ramsey hunt syndrome
What is shingles caused by?
Reactvation of latent chicken pox virus in genicular, spiral, and vestibular ganglion, and VII nerve sheath
Is shingles the 2nd most common cause of facial nerve palsy?
Yes
What is the earliest symptom for shingles?
Pain and painful rash in the ear canal, concha, or below/behind the pinna
The rash is causes by the virus localizing in the skin and resulting in painful blister eruptions
Is cranial nerve 8 involved in shingles?
Yes
Can cause hearing loss and vertigo
How is shingles treated?
Symptoms begin to resolve within 12 to 14 days
Medical intervention required
Antiviral drugs and steroids
What is seborrheic dermatitis?
Etiology is uncertain
Believed to be an infection by a yeast-like organism (Malassezia furfur)
Results in scaly superficial eczematous dermatitis
Not contagious
Does seborrheic dermatitis often cause otitis externa?
Yes
What is the treatment for seborrheic dermatitis?
Decrease yeast colonization and inflammation by antimycotic drugs, topical steroid cream and drops
What does neoplasm mean?
New tissue
Can a neoplasm either be malignant or benign?
Yes
What are some benign neoplasms?
Cysts and keloids
What is a cyst?
Fluid filled cavity
What is a keloid?
Benign outward growth of scar tissue
Results in a skin bump
Happens after a piercing or after surgery
Also after viral infections like herpes varicella zoster
What are sebaceous cysts?
Fluid filled cysts that are seen following trauma, such as an ear piercing
Can become secondarily infected
What is the treatment for a sebaceous cyst?
Antibiotics followed by surgical excision
Cut and drain fluid
Can keloids spread to surrounding or adjacent tissue?
Yes
What is the treatment for keloids?
Surgical excision and steroid injections
Are malignant neoplasms rare?
Yes
What is the most common malignant neoplasm of the auricle?
Squamous cell carcinoma
How many skin cancers are squamous cell carcinoma?
Represents 1/2 to 2/3 of all skin cancers involving the auricle
What is the most common skin cancer?
Basal cell carcinoma
Occurrence in the auricle is uncommon
What is cutaneous malignant melanoma?
6th most common cancer in the U.S.
Auricular melanomas represent 7-20% of all head/neck cutaneous melanomas
What is rhabdomyosarcoma?
Cancer of connective tissue
How common is rhabdomyosarcoma?
Most common soft tissue childhood tumor
Auricle being the 3rd most common site for this (after the orbit and nasopharynx)
What are some signs and symptoms of rhabdomyosarcoma?
Otalgia, otorrhea, bleeding, and bone destruction
Are foreign objects in the ear canal a frequently occurring problem?
Yes
What are some foreign objects that are commonly found in ear canals?
Beads
Insects
Food
Pebbles
Small alkaline batteries that can cause chemical burns