20 - Ears Flashcards
Label the different parts of the ear.
Label the different parts of the ear drum.
Anterosuperior quadrant is above the cone of light
What is the nerve supply to different parts of the pinna, and why is this important to know?
Can perform regional nerve blocks at the nerves if need to perform procedures on the pinna
Upper Lateral: Auricotemporal Nerve (CNV3)
Lower Lateral and Medial Surface: Greater Auricular Nerve (C3)
Superior Medial Surface: Lesser Occipital Nerve (C2/C3)
External Auditory Meatus: Auricular Branch of Vagus
With any trauma to the ear what important examination should you do?
Usually not urgent:
- Full Oto-Neurological exam
- If head injury may consider CT scan
How are lacerations and bites to the pinna treated?
Laceration: Primary closure with sutures after cleaning under local anaesthetic. Ensure any cartilage is covered with skin as gets its blood supply from here. If significant skin loss contact plastics
Bites: Need a strong history to find out what creature/person bit them to work out what organisms/commensals could cause an infection. Leave wound open, wound irrigation and antibiotics
What is the issue with a pinna haematoma?
When there is trauma to the ear (e.g rugby, boxer) the perichondrial blood vessels are torn and haematoma forms between auricular cartilage and the overlying perichondrium.
Cartilage can no longer get it’s blood supply from the perichondrium
If left untreated can lead to avascular necrosis and fibrocartilage overgrowth forming a structural deformity (cauliflower ear)
Also, haematoma at increased risk of infection so give abx cover
How is a pinna haematoma managed?
Drainage:
- Within 24 hours
- Aseptic field and give local anaesthetic for regional block (no adrenaline)
- Make incision along helical rim and allow haematoma to evacuate. Can then wash cavity with saline
- If only small haematoma can try needle aspiration but can reaccumulate
Pressure Dressing
- After evacuation need to apply gauze padding and tight headband or use two dental rolls with tight mattress sutures. Closes the perichondrial space and prevents re-accumulation
- If re-accumulates need to re-drain
How can temporal bone fractures be classified?
- Longitudinal (more common): lateral blow to the head and usually with conductive hearing loss
- Transverse: fronto-occipital head trauma and usually with sensorineural hearing loss or facial nerve injury
- Otic capsule sparing or otic capsule violating
What are some of the signs of a temporal bone fracture?
- Facial nerve palsy (if immediately after trauma means direct nerve damage so low chance of recovery)
- Post-auricular ecchymosis (Battle’s sign): basal skull fracture
- Haemotympanum or tympanic membrane perforation
- CSF otorrhoea or rhinnorhoea
- Hearing loss, either conductive or sensori-neural
How are temporal bone fractures managed?
- CT scan
- Admit for neuroobservation and consider surgery
- Most managed conservatively
What are some of the signs and symptoms of a tympanic membrane perforation?
Caused by blunt trauma, penetrating trauma, barotrauma and infection (e.g chronic otitis media)
- Pain (Otalgia)
- Sudden conductive hearing loss
- Ottorhoea
- Tinnitus
What investigations should you do when you suspect a TM perforation?
- View the size and location using otoscope. If any blood suction it out
- Facial nerve function tests
- Weber’s and Rinne’s test
How is a tympanic membrane perforation managed?
Uncomplicated perforation: Watch-and-wait as may heal spontaneously over 2-3 months. Strict water precauions to prevent infection e.g avoid swimming and getting water in ear when showering. Avoid blowing nose and flying
Persistent perforation: If not healed after 6/12 can refer for myringoplasty
How should haemotympanum be managed?
Blood in the middle ear due to trauma and often associated with temporal bone fracture. Can have conductive hearing loss
- Conservatively will settle over time
- Follow up in a few months to check no residual hearing loss or damage to ossicles
How does otitis externa present and what are some of the causative organisms?
Presentation: Erythematous, swollen, tender, and warm ear. Can be discharging, itchy and hearing loss
Due to any disruption in wax productive e.g repeated water exposure, trauma from cotton buds
Organisms: Pseudomonas Aeruginosa, S. Epidermidis, S. Aureus, Fungal Aspergillus
What are some risk factors of otitis externa and some differentials to consider?
Differentials:
- Otitis media with perforation
- Ramsey Hunt Syndrome
- Furuncle
How can you risk score otitits externa?
Brighton Grading Scheme
How is otitis externa managed?
- Prevention: remove any debris with microsuction, avoid swimming
- Aural Toileting: e.g irrigation or microsuction
- Topical antibiotics e.g acetic acid
- Topical steroid drops if inflammation e.g gentamicin with hydrocort
- Analgesia
- Swab any discharge in resistant cases
- If severe can use wick with topical treatment
Why is it important to check for perforations before giving treatment for otitis externa?
Gentamicin is ototoxic so don’t want it to get into middle ear
What are some complications of otitits externa?
- Malignant otitis externa
- Mastoiditis
- Osteomyelitis
- Intracranial spread
What is malignant otitis externa, how does it present and how is it managed?
- Spread of infection from soft tissue of ear to the bone usually in diabetics and immunocompromised. Usually due to P.Aeruginosa.** **Osteomyelitis of temporal bone
- Presentation: chronic ear discharge despite topical treatment, deep seated ear pain, CN palsies (usually CN VII)
- Management: refer urgent to ENT, diagnose with HRCT, urgent debridement and IV antibiotics
What is a key sign on clinical examination that points to malignant otitis externa?
Granulation tissue at the junction between the bone and cartilage in the ear cana
What are some causes of referred otalgia?
- TMJ dysfunction
- Larynx (e.g cancer)
- Tonsils (e.g warn after tonsillectomy may have otalgia)
- Posterior 1/3rd tongue
- Cervical spondylosis
What are the different types of otitis media?
What is the pathophysiology of acute otitis media?
- Usually in childhood due to ET dysfunction
- ET is shorter, straighter and wider in children so easier for organisms to migrate from nasopharynx
- Pathogens are usually respiratory as respiratory epithelium (S.Pneumoniae, Haemophilus Influenzae, Moraxella species, RSV, Rhinovirus )
What are some risk factors for acute otitis media?
- Age (peak age 6-15 months)
- Boys
- Passive smoking
- Bottle feeding
- Craniofacial abnormalities
- Winter
What are some clinical features of acute otitis media?
Symptoms: Pain due to increase pressure in tympanic cavity, malaise, fever, coryzal symptoms, tugging at ear, discharge if rupture
Signs: On otoscopy will have red bulging TM, may have tear and discharge, conductive hearing loss, cervical lymphadenopathy
If you do an ear exam and find a patient to have acute otitis media, what other exams should you do?
- Lymph nodes
- Facial nerve function tests as close to ear
- Oral and throat
- If any discharge send for MC&S
How is acute otitis media managed?
Conservative: Most resolve conservatively in 24-72 hrs, give analgesia and watch-and-wait. Can give delayed prescription
Medical: Avoid antibiotics unless risk factors for complications, continuing over 4 days, discharge from ear (swab first), systemically unwell. Usually amoxicillin
Surgery: If recurrent AOM may benefit to have grommet insertion
What are some complications of acute otitis media?
- Mastoiditis
- Meningitis
- Facial Nerve Palsies
- Intracranial Abscess
- Sigmoid sinus thrombosis
- Chronic Otitis media
- TM perforation
How does mastoiditis present and how is it managed?
Infection spreads to mastoid air cells and causes necrosis and subperiosteal abscess. This can lead to intracranial spread and meningitis
Erythematous swelling behind the ear that can push the pinna forward. TM will show AOM (bulging red TM)
Management: IV antibiotics. If no improvement after 24h do CT head and consider mastoidectomy
What is the definition of recurrent AOM and why is it important to refer these to ENT?
3 or more distinct episodes of AOM in the past 6 months
OR
4 or more in the past twelve months, 1 of which was in the last 6 months
Could be a nasopharyngeal cancer that is blocking the ET. If have conductive hearing loss, persistent cervical lymphadenopathy or nasal obstruction with recurrent AOM also refer
Which patients with AOM should you admit?
What are the different types of chronic otitis media?
- Active (discharging) or Inactive
- Squamous (Retraction pocket) or Mucosal (Ruptured TM)
What is the aetiology of chronic mucosal otitis media?
- Recurrent acute otitis media (most common)
- Grommets
- Craniofacial abnormalities
- Previous traumatic TM perforation
What are the clinical features of chronic mucosal otitis media?
- Chronically discharging ear (<6 weeks)
- Absence of fever or otalgia
- Possible conductive hearing loss
- TM perforation on otoscopy
What investigations should you do with chronic mucosal otitis media?
- Test facial nerve function
- Audiograms and Tympanometry
- Microbiological swabs
- If any suspicion of cholesteatoma do CT scan of the petrous temporal bone
How is chronic mucosal otitis media managed?
Medical
- Aural toileting, topical steroids, topical abx
- Keep ear clean and dry
- Should resolve spontaneously
- Refer to ENT if symptoms >6 weeks
Surgical (close perforation to restore hearing)
- Myringoplasty: closure of perforation in pars tensa by patching on graft from tragal cartilage
- Tympanoplasty: myringoplasty with reconstruction of ossicular chain
What is the aetiology of chronic squamous otitis media?
- Acquired (most common): chronic negative middle ear pressure from Eustachian tube dysfunction causes retraction pocket
- Congenital: choleasteatoma with no previous trauma or ear surgery
Retraction pocket can trap keratinised squamous cell debris, leading to formation of cyst-like structure which may evolve into a cholesteatoma
Which type of retraction pockets are at high risk of developing into a cholesteatoma and why are cholesteatomas so dangerous?
High risk: attico-antral (postero-superior)
Low risk: tubotympanic (antero-inferior)
Choleasteatoma can induce inflammation in the adjacent temporal bone. This can lead to destruction of the following and the following symptoms:
- Ossicles (conductive hearing loss)
- Semicircular canals (vertigo)
- Cochlea (sensorineural hearing loss)
- Facial canal (CNVII palsy)
- Erosion into intracranial cavity (meningitis, intracranial abscess, sinus thrombosis)
What are some risk factors for chronic squamous otitits media (cholesteatoma)?
- Recurrent acute otitis media
- ET dysfunction
- Prior otological surgery
- Children (more aggressive course)