Ear - Chapter 4 (Diseases of the external ear) Flashcards
Congenital anomalies in the external ear?
A- Anomalies in the shape :
* Anotia : absent auricle
* Microtia: small deformed auricle
* Macrotia: abnormally large auricle
* Bat ear: abnormal protrusion of the auricle (the commonest congenital anomaly of the auricle)
- Treatment : plastic surgery
B- Acessory auricle :
* Preauricular remnants formed of skin and cartilage.
- Treatment : surgical excision
C- Preauricular sinus (fistula) :
* usually anterior to the helix
* may be symptomless
* when infected it causes recurrent abscess formation and discharge.
- Treatment :
* No treatment for asymptomatic cases.
* Drainage of the abscess followed by excision of the track .
Traumas of the auricle ?
A- Laceration :
Etiology :
* Sharp trauma : as knife injury, bite or pulling of an earring.
Clinical picture :
* Lacerations of the skin with or without involvement of the cartilage.
* In severe cases : the auricle is partially or completely avulsed.
Complication :
* Infection : Perichondritis.
Treatment :
* Antibiotic therapy.
* Immediate plastic repair.
B- Hematoma of the auricle :
* Subperichondrial collection of blood.
* Due to trauma (boxers) or spontaneous (as in blood diseases).
* Cystic swelling which is red and tender.
* Infection which results in perichondritis.
Treatment :
* Antibiotic.
* Aspiration (early) or incision and evacuation (in late) followed by pressure bandage to prevent recollection of blood.
Inflammation of the auricle ?
Perichondritis :
Etiology:
* Infected hematoma, laceration or skin incision.
* Spread of infection from a furuncle in external canal.
Clinical picture:
* Fever, headache, malaise
* The auricle is swollen red, hot and tender (the lobule is free because it is devoid of cartilage)
Complication :
Infection → ischemia + pus → cartilage necrosis → fibrosis → cauliflower ear.
Treatment :
* Antibiotic.
* Drainage with removing necrotic cartilage.
Tumors of the auricle ?
-Benign :
Papilloma, chondroma and haemangioma.
-Malignant :
* Basal cell carcinoma : in the form of ulcer (inverted edges) with no lymph node enlargement, treated by surgical excision.
* Squamous cell carcinoma: in the form of ulcer (everted edges) with lymph node enlargement.
Treatment:
* Excision or radiotherapy
* Neck dissection (with enlarged cervical lymph nodes)
Congenital atresia of the external canal ?
- Failure of canalization of the external canal
- Unilateral or bilateral
- May be associated with congenital anomalies of the auricle, middle ear and rare inner ear
Investigations :
* CT scan: to evaluate the degree of atresia, condition of the middle and inner ear.
* Audiological : ABR to assess type and degree of hearing loss.
Treatment :
* Unilateral cases : plastic surgery after puberty.
* Bilateral cases :
- Hearing aid after few months of age to help speech development.
- Reconstructing surgery at the age of 6 years in one ear, and the other ear after puberty.
- Bilateral dead ear: lip reading and cosmetic surgery.
Traumas of external auditory canal?
1- Laceration of external canal :
* Causes: either self inflicted or unskilled ear wash or foreign body removal.
* Mild bloody otorrhea and laceration is seen on examination
* It may be complicated by otitis externa.
Treatment :
Antibiotic with steroid ear drops.
2- Longitudinal fracture of the temporal bone: Mentioned later
3- Foreign body (F.B) :
Common in children and may be :
* Animate :
- As mosquito, fleas or flies.
- Produce much discomfort and noise.
- If alive, it should be killed by oil then removed by ear wash.
* Inanimate :
- Vegetable : as seeds and beans may absorb water and swell so, use a hook to extract them and do not use ear wash.
- Non vegetable : as a piece of paper or metallic F.B :
a- Usually asymptomatic or may cause conductive deafness.
b- Ear wash is the treatment of choice.
* Impacted F.B :
- Postauricular incision may be needed under general anaesthesia.
Complication :
* Usually due to unskilled attempts during removal of Foreign bodies. It includes :
- Skin or tympanic membrane injury.
- Impaction
- Later infection (otitis externa)
4- Traumatic rupture of the drum
The tortuous direction of the ext. canal protects the tympanic membrane.
Etiology :
* Indirect trauma : Due to rapid and marked pressure changes in the
external canal :
- Hand slap (commonest).
- Otitic barotraumas.
- Explosion.
* Direct trauma :
- Foreign body.
- Self-inflicted e.g by a hair pin.
- Unskilled ear wash or instrumentation.
- Longitudinal temporal bone fracture.
Signs :
* Blood in the ext. meatus
* Perforation characterized by :
- Always central in pars tensa.
- Usually small in size
- Irregular hyperemic sharp edge (D.D with pathological perforation).
* In self inflicted perforation: the perforation is small, in post superior part of tympanic membrane and associated with hesitation marks in the ext. canal).
* Conductive hearing loss.
Treatment :
In most cases the perforation heals within few weeks
A) Conservative :
* Avoid ear contamination from water, ear drops & nose blowing
* prophylactic antibiotic.
B) Surgery :
Myringoplasty if the perforations fails to heal after 3-6 months.
The differences between traumatic and pathological tympanic membrane perforation
Localized otitis externa (Furuncle)
Localized suppurative infection of a hair follicle in the skin lining of the external canal.
Causative organism :
* Staphylococcus aureus.
Predisposing factors :
* Scratching the canal skin : by a contaminated ear bud, hair grip.
* Debilitating diseases : as diabetes mellitus.
Symptoms :
* General symptoms : Absent : because the area of suppuration is very small.
* Local symptoms :
- Earache : severe (because the skin is tightly attached to the perichondrium) throbbing and increases on moving the jaw e.g during mastication (because the external canal lies immediately behind the tempro-mandibular joint).
- Hearing loss : when the furuncle is large and occludes the external canal.
Signs :
* The furuncle : a localized red tender swelling in the outer cartilaginous 1/3 of the external canal.
* Otorrhoea : scanty and purulent (never mucoid), when the furuncle ruptures.
* Tenderness : on pulling the auricle or pressure on the tragus.
* Pre-auricular and post-auricular lymphadenitis.
Differential diagnosis : Acute mastoiditis (mentioned later).
Treatment :
1- Systemic treatment :
* Antibiotics.
* Analgesics.
2- Local treatment :
* Aural toilet i.e repeated removal of the ear discharge by suction or dry mopping.
* Packing the canal with a gauze strip soaked with antibiotics/ steroids ear drops or glycerin ichthyol 10% (glycerine is hygroscopic : reduces edema and ichthyol is counter-irritant reduces pain).
Diffuse otitis externa
- Diffuse inflammation of the skin lining of the external canal.
- Causative org. : Staph aureus and may be pseudomonas.
Predisposing factor :
* Self-inflicted : scratching the canal skin by a contaminated ear bud, hair grip.
* Iatrogenic : unskilled ear wash or instrumentation.
Symptoms :
* Earache : severe and increases on moving the jaw e.g during mastication.
* Hearing loss : when edema is severe and occludes the external canal.
Signs :
* Diffuse redness, edema and tenderness of the skin of the external canal.
* Otorrhoea : scanty and serous or purulent (never mucoid).
* Tenderness : on pulling the auricle or pressure on the tragus.
* Pre-auricular and post-auricular lymphadenitis.
Treatment :
* Systemic treatment :
- Antibiotics.
- Analgesics.
* Local treatment :
- Aural toilet.
- Packing the canal with a gauze strip soaked with antibiotics/steroids drops.
- Avoid entry of water into the external auditory canal during head wash and swimming.
Malignant otitis externa
Pathology :
* causative organism : Pseudomonas aeruginosa.
* occurs in immunocompromised patients and usually affects old diabetics.
* angiopathy (of diabetic) is responsible for aggressive spread.
* Spread of infection to :
- Skull base (osteomyelitis) → facial n. paralysis and Jugular foramen syndrome (9, 10 and 11 cranial nerves)
- Big vessels of the neck
- Intracranial spread.
Clinical picture:
* Starts as otitis externa (but with severe pain) which dose not respond to treatment.
* Granulation tissues at the junction of bony and cartilaginous parts.
* Scanty, sanguineous and purulent discharge.
* facial and other cranial nerves palsies (late).
Investigations :
* CT scan of temporal bone and skull base.
* Biopsy to exclude malignancy.
* Culture and sensitivity for the discharge.
* Blood and urine tests for sugar.
Treatment :
* Control of diabetes.
* Massive antibiotic therapy e.g quinolones or 3rd generation cephalosporine should be continued till complete cure (usually several weeks).
* Analgesics.
* Aural toilet and antibiotics ear drops.
* Surgical treatment : removal of granulations and debridement of necrotic tissues.
FUNGAL (OTOMYCOSIS)
- Causative organism: Aspergillus niger and candida albicans.
- Predisposing factors :
- Wetness and humidity.
- Prolonged use of local antibiotic ear drops.
Symptoms :
* Itching is the main symptoms.
* Pain (from secondary infection).
* Hearing loss (from fungal mass).
Signs :
* The external canal skin is red and edematous.
* Fungal mass which may be :
- White mass with black spots (Aspergillus niger) like a wet newspaper in the meatus.
- White scattered spots (candida albicans).
Treatment :
* Removal of the fungal mass by suction, ear wash followed by dry mopping.
* Antifungal ear drops or creams e.g Clotrimazole (canesten or dermatin) + 2% salicylic acid (keratolytic) in alcohol (anti-fungal).
* Keep the ear dry.
VIRAL OTITIS EXTERNA
(A) Bullous myringitis :
Viral infection (Herpes simplex virus) of the tympanic membrane.
* Severe ear ache.
* Yellowish or sanguineous watery discharge after rupture of the bullae.
* On exam: Reddish bullae on the tympanic membrane
Treatment : Analgesics
(B) Herpes zoster oticus (Ramsay – Hunt syndrome) :
Viral infection (Herpes zoster virus) of the skin covering of the auricle and the skin lining of the external canal.
Clinical picture :
* Severe earache.
* Serosanguinous otorrhea after rupture of the bullae.
* Reddish bullae on the auricle and in the external canal.
* After few days they rupture → a serosanguinous exudates but pain may persist.
N.B : Herpes zoster oticus may be associated with ipsilateral :
1- Lower motor neuron facial nerve palsy due to affection of the geniculate ganglion.
2- Sensori-neural hearing loss and vertigo due to affection of the cochleovestibular nerve.
The triad of : (a) herpes zoster oticus, (b) facial nerve palsy and (c) sensorineural hearing loss and vertigo is called Ramsay-Hunt syndrome.
Treatment :
* Analgesics.
* Anti-viral therapy as acyclovir (oral and local).
* Corticosteroids in severe cases with affection of the facial nerve and/or cochleo-vestibular nerve
Non infectious otitis externa
A) Eczematous (Allergic) otitis externa :
* Allergic dermatitis of ext. canal skin due to antibiotic ear drops.
* Itching is the main symptoms.
* The skin shows red, edema and vesicles (Acute cases) or fissures and scales (in chronic cases).
Treatment :
* Avoid predisposing factors.
* Corticosteroids drops and cream.
* Antihistaminic.
B) Seborrheic otitis externa :
* A greasy, scaling and crusting condition affecting the skin of the ear and scalp.
* It is due to abnormal quantity and quality of the sebum and wax.
* The cartilaginous portion of the canal and the postauricular sulcus are usually affected.
* Itching is the main symptom.
Treatment :
* The scalp should be treated by keratolytic shampoo.
* Cream containing salicylic acid and sulphur 2% or hydrocortisone and antibiotic cream.
TUMORS OF THE EXTERNAL CANAL
Benign : Exostosis, papilloma and ceruminoma.
Exostosis :
* It is the commonest benign tumour of the ext. auditory canal.
* It is a new bone formation projects into the lumen of the bony canal.
* 3 types may be seen :
- Sessile : which is the commonest, usually bilateral, multiple and formed of ivory bone. It is common in swimmers due to recurrent irritation by cold water.
- Pedunculated : unilateral, single and formed of cancellous bone.
- Diffuse : which is not a true neoplasm, formed of circumferential hyperostosis.
Clinical picture :
* If it is small, it may be symptomless.
* If it is large, it may cause irritation and hearing loss.
Treatment :
* Small tumour : no treatment.
* Large tumour : surgical excision by electric burr.
Malignant :
Squamous cell carcinoma
* The commonest malignant tumors of external canal.
* Appears as fleshy friable mass which bleeds on touch.
* Blood stained offensive discharge.
* Facial paralysis.
Treatment :
* Resection of temporal bone with post operative radiotherapy.
* Neck dissection in presence of palpable cervical lymph node.
Ear wash
Indications :
* Impacted wax.
* Foreign body :
- Animate (after it is killed by oil).
- Inanimate (small, non-vegetable).
* Fungus debris (otomycosis).
Contraindications :
* Impacted F.B.
* Big vegetable F.B.
* Tympanic membrane perforation.
* Otitis externa.
* Otitis media.
Technique :
* The solution used is sterile isotonic saline or water at body temperature.
* Fill the syringe and expel air bubbles.
* A small basin is held by the patient below his ear.
* Pull the auricle backwards, upwards and outwards to straighten the meatus.
* Direct the saline or water along the posterosuperior metal wall (to avoid rupture of the drum).
* Dry the meatus completely after washing.
Complication :
* Injury of the canal skin or tympanic membrane (if direction of the syringe be wrong).
* Otitis externa (fungal) if fluid or instruments are net sterile.
* Otitis media (if there are previous perforation).
* Scalding of the ext. canal skin by very hot fluid.
* Irritation of :
- Inner ear by very hot or very cold water leading to vertigo and nystagmus (vestibular stimulation).
- Auricular branch of vagus nerve leading to reflex cough and vasovagal attack (vagal stimulation).
