Ear Disorders Comprehensive Notes PDF

Ear Disorders: Comprehensive Notes 1. Anatomy Overview ​ External Ear: Auricle (pinna), external auditory canal (EAC). ​ Middle Ear: Tympanic membrane (eardrum), ossicles (malleus, incus, stapes), mastoid air cells. ​ Inner Ear: Cochlea (hearing), vestibular apparatus (balance). ​ Eustachian...

Ear Disorders: Comprehensive Notes 1. Anatomy Overview ​ External Ear: Auricle (pinna), external auditory canal (EAC). ​ Middle Ear: Tympanic membrane (eardrum), ossicles (malleus, incus, stapes), mastoid air cells. ​ Inner Ear: Cochlea (hearing), vestibular apparatus (balance). ​ Eustachian Tube: Connects nasopharynx to middle ear (pressure equalization). 2. External Ear Disorders 2.1 Otitis Externa (Swimmer’s Ear) ​ Definition: Inflammation/infection of the external auditory canal (EAC). ​ Common Causes: Pseudomonas aeruginosa, Staphylococcus aureus. ​ Clinical Features: ○​ Severe ear pain (otalgia), often out of proportion due to the thin skin in the bony canal. ○​ Scanty discharge (otorrhea). ○​ Canal is often edematous, obstructed; tympanic membrane may be difficult to visualize. ○​ Possible conductive hearing loss due to canal occlusion. ​ Management: ○​ Topical antibiotics +/- topical steroids (to reduce edema and inflammation). ○​ Ear wick (or “Pope wick”) insertion if canal is too edematous—allows medication to reach deeper. ○​ Systemic antibiotics only if severe infection, immunocompromised patient, or if topical therapy fails. ○​ Analgesia is crucial. ○​ Keep ear dry (avoid water exposure). 2.1.1 Furunculosis (Localized Otitis Externa) ​ Definition: Localized infection of a hair follicle in the lateral (cartilaginous) portion of the EAC. ​ Symptoms: Pain, possible localized swelling/abscess. ​ Management: Topical or oral antibiotics, incision, and drainage if abscess forms. 2.1.2 Otomycosis (Fungal Otitis Externa) ​ Common Organisms: Candida albicans, Aspergillus species. ​ Clinical Features: ○​ Itching (pruritus) more prominent than pain. ○​ Ear blockage, possible whitish or blackish discharge/spores. ○​ Common in humid environments or immunocompromised patients. ​ Management: ○​ Careful suctioning/debridement of fungal debris. ○​ Topical antifungals (e.g., clotrimazole, nystatin). ○​ Address underlying immunocompromise if present. ○​ Keep canal dry. 2.1.3 Viral Otitis Externa (Herpes Oticus) ​ Cause: Viral infection that can present with small vesicles in the EAC.  ​ Symptoms: Pain, vesicular rash, potential facial nerve involvement (if virus affects nerve ganglia → Ramsay Hunt syndrome). ​ Management: ○​ Supportive care, analgesics. ○​ Antivirals (e.g., acyclovir) sometimes used if facial nerve paralysis or severe involvement. 2.2 Malignant (Necrotizing) Otitis Externa ​ Definition: An aggressive infection that extends from the EAC to the skull base (osteomyelitis), often in immunocompromised or diabetic patients. ​ Most Common Organism: Pseudomonas aeruginosa. ​ Clinical Features: ○​ Severe, persistent otalgia (often worse at night). ○​ Granulation tissue in the ear canal (frequently at the bone-cartilage junction). ○​ Possible cranial nerve palsies (facial nerve, etc.). ​ Management: ○​ Prolonged anti-pseudomonal therapy (8–12 weeks): IV or oral fluoroquinolones (e.g., ciprofloxacin). ○​ Debridement of granulation. ○​ Control underlying immunosuppressive state (e.g., optimize diabetes management). 2.3 Ear Trauma ​ Auricular (Pinna) Trauma: ○​ Hematoma (subperichondrial) must be drained to prevent necrosis and cauliflower ear. ○​ Suture lacerations if needed; ensure no infection. ​ External Canal Trauma: ○​ Can cause lacerations or bleeding; ensure no tympanic membrane (TM) perforation. ○​ Manage with antiseptic measures, possibly ENT evaluation. ​ TM (Eardrum) Rupture: ○​ Causes: Direct trauma (e.g., Q-tip, slap to ear), barotrauma (blast injury), or infection. ○​ Presentation: Sudden pain, possible bloody otorrhea, hearing loss, tinnitus. ○​ Most heal spontaneously if small; advise water precautions. ○​ Check hearing to rule out ossicular chain disruption. ○​ If not healed in 3–6 months, may need myringoplasty. 3. Middle Ear Disorders 3.1 Otitis Media 3.1.1 Acute Otitis Media (AOM) ​ Definition: Acute inflammation of the middle ear, commonly in children. ​ Pathogens: Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis. ​ Clinical Features: ○​ Ear pain, fever, irritability. ○​ TM: Red, bulging, possible decreased mobility. ○​ Can progress to TM perforation → purulent discharge (pain may lessen post-perforation). ​ Management: ○​ Systemic antibiotics (e.g., amoxicillin-clavulanate) for 7–10 days. ○​ Analgesics, antipyretics. ○​ In mild pediatric cases, observe for 48 hours if no red flags (but guidelines vary). 3.1.2 Chronic Suppurative Otitis Media (CSOM) ​ Definition: Chronic perforation of the tympanic membrane with persistent or recurrent ear discharge (>6 weeks). ​ Subtypes: ○​ Safe (Tubotympanic): Central perforation, less risk of complications. ○​ Unsafe (Atticoantral): Marginal or attic perforation, higher risk of cholesteatoma/ complications. ​ Clinical Features: ○​ Otorrhea (often foul-smelling in the unsafe type). ○​ Usually painless, but can have mild discomfort. ○​ Conductive hearing loss. ​ Management: ○​ Aural toilet (suctioning, cleaning). ○​ Topical antibiotics (e.g., quinolone drops). ○​ Water precautions. ○​ Surgery (tympanoplasty, mastoidectomy) for persistent perforation or cholesteatoma. 3.1.3 Otitis Media with Effusion (OME) / Serous Otitis Media / “Glue Ear” ​ Definition: Fluid in the middle ear without acute signs of infection. ​ Causes: Eustachian tube dysfunction (e.g., adenoid hypertrophy, cleft palate, allergy). ​ Symptoms: Hearing loss, fullness, no significant pain. Common in children. ​ Management: ○​ Address underlying cause (e.g., allergic rhinitis, adenoid hypertrophy). ○​ Observe if mild; many cases resolve spontaneously.  ○​ Myringotomy with ventilation tube (grommet) if persistent, especially with significant hearing loss. 3.1.4 Barotrauma (Aerotitis) ​ Definition: Middle ear injury due to pressure changes (flying, diving). ​ Clinical Features: ○​ Ear pain, TM retraction, possible fluid or hemorrhage behind TM. ○​ Can lead to acute serous otitis media. ​ Management: ○​ Decongestants, nasal steroids to help Eustachian tube function. ○​ Avoid rapid pressure changes (chewing gum, swallowing, “Valsalva” during descent). ○​ Usually self-limiting; persistent cases may need ventilation tubes. 3.2 Cholesteatoma ​ Definition: Keratinizing squamous epithelium in the middle ear or mastoid that can erode surrounding structures. ​ Pathogenesis: ○​ Retraction pockets (often in the pars flaccida). ○​ TM perforation with squamous epithelium migration. ○​ Congenital cholesteatoma (rare). ​ Clinical Features: ○​ Foul-smelling otorrhea, conductive hearing loss. ○​ Can erode ossicles, facial nerve, semicircular canal → serious complications. ​ Management: ○​ Surgical (mastoidectomy) to remove all cholesteatoma. ○​ Reconstruction (tympanoplasty) may follow. 3.3 Mastoiditis and Other Extracranial Complications ​ Mastoiditis: Infection spreads to mastoid air cells; presents with postauricular pain, swelling, possible subperiosteal abscess. ​ Labyrinthitis: Spread of infection to the inner ear → vertigo, sensorineural hearing loss. ​ Petrositis: Inflammation of the petrous apex (rare). ​ Facial Nerve Paralysis: Inflammatory or compressive lesion in the middle ear/mastoid. 3.4 Intracranial Complications ​ Dural Abscess ​ Lateral Sinus Thrombophlebitis ​ Meningitis ​ Brain Abscess (temporal lobe or cerebellum) ​ Otitic Hydrocephalus High-Yield Note: Any persistent headache, neurological deficit, or severe systemic symptoms in a patient with chronic otitis media should raise suspicion for intracranial extension. 4. General Clinical Presentations 4.1 Otorrhea (Ear Discharge) ​ Can arise from external ear (e.g., otitis externa, trauma) or middle ear (TM perforation, CSOM). ​ Character (scanty vs. profuse, foul-smelling vs. odorless) may suggest diagnosis (e.g., foul odor suggests cholesteatoma). 4.2 Otalgia (Ear Pain) ​ Primary: From external or middle ear pathology. ​ Referred: Throat lesions (tonsil, base of tongue, larynx), temporomandibular joint, or dental issues can refer pain to the ear via cranial nerves (CN V, VII, IX, X). 4.3 Hearing Loss ​ Types: ○​ Conductive: Lesion in external or middle ear (e.g., wax impaction, otitis media, ossicular disruption). ○​ Sensorineural: Lesion in cochlea or auditory nerve (e.g., presbycusis, noise-induced hearing loss, acoustic neuroma). ○​ Mixed: Combination of both. ​ Basic Evaluation: ○​ Pure tone audiometry (PTA): Air and bone conduction thresholds. ○​ Tympanometry: Assess middle ear pressure and TM mobility (Type A = normal, Type B = no mobility/fluid, Type C = negative pressure). ○​ Additional tests: Otoacoustic emissions, Auditory Brainstem Response in special cases. 4.3.1 Conductive Hearing Loss - Key Examples ​ Otitis Media (acute/chronic). ​ Otosclerosis (fixation of the stapes footplate). ​ External ear obstruction (e.g., cerumen, foreign body). 4.3.2 Sensorineural Hearing Loss - Key Examples ​ Presbycusis: Age-related degeneration of cochlear hair cells. ​ Noise-induced: Damage from prolonged loud noise. ​ Acoustic Neuroma (Vestibular Schwannoma): Usually unilateral hearing loss, tinnitus, ± facial numbness (CN V involvement). 4.4 Vertigo and Imbalance ​ Definition: A false sense of movement—often “spinning.” ​ Causes: ○​ Peripheral (inner ear/vestibular): Benign paroxysmal positional vertigo (BPPV), Meniere’s disease, labyrinthitis. ○​ Central: Brainstem/cerebellar lesions. ​ History Points: Duration, triggers (head movement), associated hearing loss or tinnitus, neurological symptoms. ​ Common Peripheral Causes: ○​ BPPV: Short episodes triggered by position changes (seconds). ○​ Meniere’s: Recurrent episodes (20–30 minutes to hours), with hearing loss, tinnitus, aural fullness. ○​ Vestibular Neuritis/Labyrinthitis: Prolonged (days), often after viral infection; may have hearing loss (labyrinthitis). 5. High-Yield Considerations 1.​ Otitis Externa: Severe pain, edematous EAC, often Pseudomonas. Topical drops are mainstay. 2.​ Malignant Otitis Externa: Elderly/diabetic, severe nocturnal pain, granulation tissue, cranial nerve involvement—urgent anti-pseudomonal treatment. 3.​ Acute Otitis Media: Common in children; ear pain, fever, red bulging TM. Treat with antibiotics, analgesics. 4.​ Chronic Suppurative OM: Persistent discharge through TM perforation; watch for cholesteatoma if “unsafe” (atticoantral). 5.​ Cholesteatoma: Aggressive squamous epithelium in middle ear—foul discharge, erodes bone. Needs surgical removal. 6.​ Conductive vs. Sensorineural Hearing Loss: Use tuning fork tests (Rinne, Weber) and audiometry to distinguish. 7.​ Vertigo: Differentiate peripheral vs. central by duration, triggers, associated ear symptoms, neurologic signs. 8.​ Complications: Mastoiditis, labyrinthitis, petrositis, intracranial spread—suspect if persistent fever, retroauricular swelling, severe headaches, or neurological deficits. In Conclusion: Ear disorders range from external ear infections to middle ear pathologies and can present with pain, discharge, hearing loss, and vertigo. You have to look for the “red flags” (e.g., severe nocturnal ear pain in diabetics suggesting malignant otitis externa, foul-smelling discharge in suspected cholesteatoma, or signs of intracranial complications). Diagnostics often involves otoscopy, audiometry, and imaging (CT/MRI), if indicated. Treatment include topical therapies (e.g., otitis externa) to major surgery (e.g., mastoidectomy for cholesteatoma). By Abdulaziz Alnufaei - B18