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
What do patients complain of when they have insects in their ears?
Itching or tickling sensation or patients report that they can hear something “moving”
How are foreign objects removed from the ear canal?
Hook or suction
With or without local anesthesia
How does ear canal stenosis occur?
Ear canal fails to completely develop during the 7th month in utero
Resulting in a very narrow ear canal
What does stenosis lead to?
Difficulty examining the ear canal
Collection of wax and debris
Possible conductive hearing loss
Can external auditory stenosis be repaired?
Yes, by canalplasty
What can failure of canalization of the EAC result in?
Aural atresia
Is atresia more common one sided?
Yes
Is atresia more common in males?
Yes
Is atresia often associated with microtia and middle ear anomalies?
Yes
Is atresia sporadic?
Yes
It may occur in associated with a known syndrome including treacher collins, trisomy 22, crouzons syndrome, and hemifacial microtia
1st and 2nd arch syndrome
How can you establish cochlear function in children with unilateral and bilateral atresia?
Bone conduction ABR
Why can you not do normal ABR on someone with atresia?
No canal
When does aural atresia occur in development?
After inner ear development
Most patients have normal cochlear function but have a max CHL
Is the incidence of inner ear malformations higher in the atresia population compared to the general population?
Yes
When should the repair of atresia take place?
After the repair of a coexisting microtia
When does surgical repair of atresia usually occur?
Around age 6 to 8 years because the auricle is close to full size by then
What type of device is FDA approved for people with atresia over age 5?
BAHA
Can children who are younger than 5 have a BAHA?
Yes with a soft or hard headband
What is a BAHA?
Utilizes direct percutaneous coupling of a vibrating transducer to a titanium implant anchored in the temporal bone
What are collapsing canals?
Canals collapse when supra-aural headphones are placed over ears
Who are at risk of collapsing canals?
People in the extremes of age
Younger children and older adults
Because of soft and deteriorating cartilage
What should you do to evaluate a patient that is at risk for collapsing canals?
Exert pressure on portions of the pinna cartilage around the opening of the ear canal where the supras sit during examination
What can happen with someone with a large tragus?
It can be flattened across the EAC opening by the pressure of the headphones
Creating a collapsing canal effect
How much hearing loss can an occluded canal cause?
Up to 50 dB HL hearing loss
What are the audiological findings of collapsed ear canals?
Normal tymps
A conductive loss present only at or worse at high frequencies with supras
Will thresholds with collapsing canals be better with inserts or the sound field?
Yes
What should you do to manage the collapsing canals?
Use inserts
Placement of immittance probe tips in the ear canal
Use of stock ear molds to keep canal open
Pull the pinna up and back when placing the headphones
Hold the headphone against the ear rather than fixing it against the canal
Could some of the management methods for collapsing canals result in high frequency attenuations?
Yes, for example the placement of immittance probe tips in the ear canal and the use of a stock ear mold
What is epithelial migration?
Cerumen and dead skin carried out of the EAC by a lateral migratory property of the squamous epithelium (Skin) lining the ear canal
Does cerumen tend to be drier with age due to reduced number and activity of ceruminous and sebaceous glands?
Yes
Can the natural process of cerumen secretion and export be affected?
Yes, by a number of processes
Leads to cerumen impaction
Is impaction more common in males?
Yes
Due to thicker and coarser hairs found at the lateral end of the EAC
What are different things that can impede the natural flow of cerumen?
Narrow canals, over-zealous use of q-tips, and a hearing aid/earmold
What are some audiological findings for cerumen impaction?
Sensation of obstruction
On otoscopy, cerumen blocking the ear canal; TM structures not visualized
Tymp volume less than or equal to 0.2 ml
Mild conductive loss
Otalgia
Vertigo and dizziness
Coughing (via Arnolds nerve, branch of X nerve in the EAC)
How do you manage cerumen impaction?
Cerumen removal by medical personnel
Cerumen softening by cerumenolytic agents like olive oil, Murine, and Debrox prior to removal
Do you need to do a tymp to verify an obstruction?
Yes
Will look kinda like a flat tymp if there is no opening
Can you proceed with a hearing test when there is some opening with cerumen impaction?
Yes
But proceed with caution
Send to get it removed if affecting testing
What are inflammatory polyps?
Abnormal tissue growth that can happen anywhere in the body
Can present as masses in the EAC
What are inflammatory polyps typically seen with?
Chronic otitis media with or without cholesteatoma
What are some causes of inflammatory polyps?
Foreign bodies in the EAC or TM such as retained PE tubes, canal cholesteatoma, and benign or malignant tumors
Are polyps painful?
Most are not
Respond to topical therapy and steroid-antibiotic drops
What happens if healing doesn’t happen for inflammatory polyps with topical treatment?
Biopsy is needed
Can inflammatory polyps obstruct opening of canal?
Yes
What is otitis externa?
Swimmer’s ear
Inflammatory condition of skin lining in EAC
Most common condition affecting the EAC
What are some of the cause of otitis externa?
Local trauma
Frequent swimming
Spontaneously
What type of infection is otitis externa?
Could be acute, chronic, diffuse, or localized
What is acute diffuse otitis externa?
Type of otitis externa
Typically bacterial infection
Caused by local trauma, frequent swimming, or spontaneously
What are some audiological findings for acute diffuse otitis externa?
Severe pain
Generally conductive hearing loss
Whitish, watery otorrhea
Acute swelling that may be severe enough to close the EAC
What is the treatment for acute diffuse otitis externa?
Analgesics for pain
Topical antibiotics and steroids
Removal of infected debris by physician
What is acute localized otitis externa?
Mainly consists of two forms
Furuncle (abscess) and bullous myringitis
What is a furuncle?
A staphylococcus aureus infection of a hair follicle in the EAC
Extremely tender and painful, but self-remitting in a few days
Symptomatic treatment for pain if needed
What is a bullous myringitis?
Localized viral (e.g., influenza or herpes zoster) or bacterial infection (e.g., Strep. pneumoniae) of TM and deep EAC
Results in blood blisters of various sizes
Extremely painful but again self-remitting in a few days
What is the treatment for bullous myringitis?
Symptomatic for pain
Cleaning of debris in the EAC by a physician
Will furuncles and bullous myringitis go away on its own?
Yes, but really painful that they might need to contact doctor
What is the treatment for chronic otitis externa?
Topical steroids
What is chronic otitis externa?
Typically a generalized condition of the EAC
The most common cause is seborrhic dermatitis believed to be caused by a yeast-like organism
Underlying skin appears red and scaly with lack of cerumen
The bigger problem is itching rather than pain
Watery discharge may occur
This condition is prone to frequent acute flare-ups
What are some complications that are present for chronic otitis externa?
Stenosis of the EAC due to inflammation
Formation of a false membrane across the EAC that may obscure the TM and result in a conductive hearing loss
When do fungal infections occur?
Spontaneously or as a result of frequent use of topical antibiotics
Why can topical antibiotics result in fungal infections?
Messes up pH of your skin and natural protections
Not able to fight off opportunistic infections (fungal and bacterial)
Are fungal infections colorful?
Yes
Ranging from blue-black, green, yellow, to white
Can fungal infections produce extensive debris?
Yes
What will patients complain of with fungal infections?
Hearing loss and/or wet feeling inside EAC
What can happen if a fungal infection is left untreated?
It can destroy sections of the EAC and mastoid bone
May cause meningitis and death
Why can fungal infections lead to meningitis?
Can travel into the ME
Thin bony plate above ME, if it erodes through the plate it can get into the meninges that surround the brain
Very dangerous
What is the treatment for fungal infections?
Topical anti-fungal medication
Removal of debris from the EAC by a physician
Are fungal infections usually diagnosed right away?
No, they tend to want to take cultures from a spinal tap
Will not show up because it is not a bacterial infection
What is necrotizing external otitis?
Historically called malignant otitis externa
Much more aggressive infection
Seen in immunocompromised patients (poorly controlled diabetic patients, HIV and AIDS patients)
Why was necrotizing external otitis called malignant?
Not a cancer, but acts like a cancer
Eats into the structures around it
Can necrotizing external otitis involve the temporal bone and skull base?
Yes
And then it is essentially osteomyelitis
Skull-base osteomyelitis
Eats into the bone
How does necrotizing external otitis begin?
Acute otitis externa but because the host is immunocompromised, the infection spreads beyond soft tissue of the ear canal to the underlying temporal bone
A chronic infection ensues with granulation and inflammatory tissue forming in the EAC replacing a significant portion of the bony EAC, which then mimics a malignant disease
Can necrotizing external otitis result in complications in the neurovascular pathways?
Yes
What can necrotizing external otitis inferior extension of the disease into the mastoid portion can result in what?
Facial weakness/paralysis
What can necrotizing external otitis medial extension into the petrous apex can result in what?
Can affect CNs V and VI
What can necrotizing external otitis inferior-medial extension can result in what?
Jugular foramen and cranial nerves IX, X, and XI
Can result in hoarseness, dysphonia, and aspiration
Necrotizing external otitis extension into the dura lining the temporal bone can result in what?
Vascular complications (sigmoid sinus thrombosis)
Intracranial complications (otic hydrocephalus and meningitis)
Should NEO always be suspected when an immunocompromised patient complains of ear pain?
Yes
How can NEO be diagnosed?
Biopsy of granulation tissue in the EAC to rule out malignant disease and obtain cultures for bacterial and fungal organisms
CT scan and MRI to evaluate the temporal bone, skull base, and soft tissue
What is the treatment of NEO?
Parental and topical antibiotics (resolves the condition in ~ 80% of patients) but may require meds for up to 6 months
Treatment of underlying immunocompromising condition (treat what caused it)
Can recurrence of NEO occur with recurrence of external otitis?
Yes
Need to be extra careful
What are some common benign neoplasms?
Exostosis and osteomas
Are exostosis and osteomas common?
Not really
What are exostosis?
Bony growth and the most common benign tumor of the EAC
Single or multiple growths
Typically bilateral, but usually starts with unilateral
What are exostosis caused by?
Localized hyperplasia (abnormal cell increase) usually due to irritation or may be idiopathic (unknown)
Common in individuals with prolonged exposure to cold water
If a exostosis is large, can it lead to CHL?
Yes
If it obstructs the EAC
What are some later stage symptoms of exostosis?
Pain/discomfort, tinnitus, and associated external otitis
What is the treatment for exostosis?
Antibiotics, analgesics, and surgical excision of the growth
Do exostosis cause symptoms if they are slow growing?
No
Might not even know that they are there
What are osteomas?
True benign bony tumors
Less common and more lateral than exostosis
Usually singular
What are the symptoms for osteomas?
Similar the exostosis
Cannot tell the difference unless biopsied
What is the treatment for osteomas?
Surgical excision
Can obstruction of EAC happen faster with osteomas?
Yes
Due to being lateral
Are malignancies of the temporal bone rare?
Yes
Incidence of 1 to 6 per 1,000,000
And malignancies of the EAC constitute ~ 25% of those cases
What are the different types of malignant neoplasms?
Squamous cell carcinoma (most common in adults)
Adenoid cystic carcinoma (rare form of adenocarcinoma, found mostly in head and neck)
Sarcoma (mostly in children)
Do malignant neoplasms have varied presentation?
Yes
May present with pain, drainage, and hearing loss, mimicking chronic otitis externa and delaying diagnosis
Should all patients presenting with non-healing granulation of tissue in the EAC be biopsied?
Yes
What is osteoradionecrosis?
Rare complication from radiation of the base of skull bones due to cancer
But idiopathic variants can also occur
Radiated bone becomes susceptible to infection and healing is compromised
What bone is most commonly affected with osteoradionecrosis?
Mandible
Can ORN occur years after the original radiation?
Yes
Can ORN be localized or diffuse?
Yes
Localized EAC ORN occurs because often EAC is the portal of radiation such as in nasopharyngeal carcinoma
Diffuse EAC disease is more common in high dose radiation to the temporal bone
What are some symptoms of osteoradionecrosis?
Ear fullness
Otalgia
Foul odor
Hearing loss (CHL or SNHL)
Discharge including bloody otorrhea
Tinnitus
Is there usually debris in the EAC for ORN?
Yes
Are there usually single or multiple areas of exposed devascularized bone in ORN?
Yes
The bone is yellowish in color and soft
Bone doesn’t have blood supply
In ORN, should persistent granulation tissue be biopsied?
Yes
Not uncommon to develop cancer where radiation was done
What is the treatment for localized ORN?
Less aggressive
In-office debridement
Topical ointments
What is the treatment for diffuse ORN?
More lethal
Surgical debridement
I/V antibiotics
What is the differential diagnosis for ORN?
Chronic otitis media
Also presents discharge and hearing loss
Delays diagnosis
