Ear pathology Notes

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Osmosis High-Yield Notes

This Osmosis High-Yield Note provides an overview of Ear pathology essentials. All Osmosis Notes are clearly laid-out and contain striking images, tables, and diagrams to help visual learners understand complex topics quickly and efficiently. Find more information about Ear pathology by visiting the associated Learn Page.
NOTES NOTES EAR PATHOLOGY GENERALLY, WHAT IS IT? PATHOLOGY & CAUSES ▪ Structural, functional pathology affecting different ear components ▪ Outer ear: auricle, pinna, ear canal ▫ Inflammation/infection → otitis externa ▪ Outer ear, middle ear: separated by tympanic membrane (eardrum); normally no air passage/fluids between two compartments ▫ Perforated eardrum → communication through tympanic membrane ▪ Middle ear: tiny chamber; contains functional ear bones (malleus, incus, stapes) ▫ Inflammatory middle ear disease → otitis media ▪ Eustachian tube: connects middle ear to nasopharynx ▫ Failure to open/close, remove secretions → Eustachian tube dysfunction SIGNS & SYMPTOMS ▪ Hearing loss ▪ Ear pain ▪ Ear discharge 564 OSMOSIS.ORG DIAGNOSIS DIAGNOSTIC IMAGING ▪ Otoscopy ▫ Tympanic membrane visualization OTHER DIAGNOSTICS ▪ Outer ear inspection ▪ Hearing screening tests (Weber, Rinne tests) ▫ Distinguishes between conductive, sensorineural hearing loss TREATMENT MEDICATIONS ▪ Topical otic drops/systemic agents ▪ Antihistamines/corticosteroids/ decongestants (guided by specific diagnosis) SURGERY ▪ Drain fluid accumulation/debride granulation tissue/repair defect
Chapter 73 Ear Pathology EUSTACHIAN TUBE DYSFUNCTION osms.it/eustachian-tube-dysfunction PATHOLOGY & CAUSES ▪ Any primary Eustachian tube function failure ▪ Failure to equalize/dilatory dysfunction ▫ Eustachian tube may not open → tympanic membrane stretches → pain Patulous dysfunction (chronic patency) ▪ Normal Eustachian tube is two-way valve (opens to equalize pressure, closed at rest) ▪ Persistent opening → irritant/bacteria entering middle ear Ciliary dyskinesia ▪ Tiny cilia line Eustachian tube, clear out middle ear mucus secretion ▪ Ciliary dysfunction/dyskinesia: cilia fail to clear section → stagnant secretion → complications (e.g. otitis media) CAUSES Failure to equalize/dilatory dysfunction ▪ Functional: inflammation (viral infection— e.g. common cold, allergy) → Eustachian tube swelling, secretion accumulation → Eustachian tube mechanical blockage → equalization failure ▪ Anatomical: regional mass pressure (e.g. tumour) or previous trauma scar/medical procedure Patulous dysfunction (chronic patency) ▪ Weight-loss (> 6 lbs/2.7 kg) → tissue atrophy (e.g. chronic illness) ▪ Chronic allergy/gastric-content reflux → mucosal atrophy ▪ Chronic gum-chewing → repeated musclefacilitated Eustachian tube opening ▪ Short, floppy Eustachian tubes (in children) → provide little resistance against middleear reflux during ↑ positive pressure on nasopharyngeal end of tube (e.g. crying/ nose blowing) Ciliary dyskinesia ▪ Acquired: toxins → ciliary damage, paralysis → mucociliary elevator failure ▫ Cilia can’t flick back and forth (e.g. cigarette smoke) ▪ Congenital: cystic fibrosis → very thick secretions not adequately cleared COMPLICATIONS ▪ Conductive hearing loss, otitis media, tympanic membrane perforation, cholesteatoma SIGNS & SYMPTOMS ▪ Affected ear is clogged, muffled ▪ Ear pain ▪ Autophony (hearing one’s own voice, breathing) ▫ Encountered primarily in patulous dysfunction ▪ If inner ear affected → balance problems DIAGNOSIS DIAGNOSTIC IMAGING CT scan / MRI ▪ Contrast in persistent effusion cases ▫ Neoplasm may cause Eustachian tube obstruction Nasal endoscopy ▪ Inflammation, secretion, allergic manifestation signs ▫ Eustachian tube opening quality (assessed through yawn, swallowing maneuvers) Otoscopic ear examination ▪ Normal tympanic membrane appears shiny, translucent OSMOSIS.ORG 565
▪ Examine for abnormality (e.g. retraction, effusion, perforation) ▫ Dull bluish-gray/yellowish coloration denotes effusion behind membrane; reddish coloration, engorged vessels signal inflammation ▪ Pneumatic examination ▫ Fluid-filled ear minimizes tympanic membrane excursion with insufflation OTHER DIAGNOSTICS ▪ Hearing tests for conductive hearing loss ▫ Weber test: sound lateralized to affected ear ▫ Rinne test: BC > AC TREATMENT MEDICATIONS ▪ Dilatory dysfunction ▫ Upper respiratory tract inflammation (viral infection, allergy) → short intranasal/systemic decongestant, corticosteroid course ▪ Patulous dysfunction ▫ Avoid decongestants/corticosteroids SURGERY ▪ Dilatory dysfunction ▫ Tympanostomy tubes: hollow tubes inserted into eardrum → create direct opening between middle, outer ear → allow easy pressure equilibration, accumulated debris drainage OTHER INTERVENTIONS ▪ Patulous dysfunction ▫ Hydration, nasal saline drops/irrigation OTITIS EXTERNA osms.it/otitis-externa PATHOLOGY & CAUSES ▪ AKA “swimmer’s ear” ▪ Outer ear canal irritation CAUSES ▪ Outer ear canal microbial infection (primary cause) ▫ Bacterial (90%): Pseudomonas aeruginosa, Pseudomonas vulgaris, E. coli, S. aureus ▫ Fungal: Candida albicans, Aspergillus niger ▪ Dermatological conditions ▫ Allergic contact dermatitis, psoriasis, atopic dermatitis 566 OSMOSIS.ORG RISK FACTORS ▪ Frequent swimming ▪ Mechanical cleaning/irritation (cotton swabs/scratching) ▪ Ear canal occlusion (hearing aid, headphone) ▪ Diabetes SIGNS & SYMPTOMS ▪ Acute (< six weeks) ▫ Pinna traction → aggravated pain ▫ Otorrea: sticky yellow discharge) ▫ Swelling, purulent debris → external canal obstruction → conductive hearing loss, +/- aural fullness ▫ Posterior auricular lymphadenopathy
Chapter 73 Ear Pathology ▫ Complicated otitis externa: periauricular soft tissue erythema, swelling ▪ Chronic (> three months) ▫ External ear canal pruritus; epidermis atrophy, scaling; otorrhea; normal tympanic membrane DIAGNOSIS LAB RESULTS ▪ Discharge ▫ Gram stain, culture OTHER DIAGNOSTICS ▪ Note physical outer ear change (discharge, erythema, scaling) ▪ Hearing tests for conductive hearing loss ▫ Weber test: sound lateralized to affected ear ▫ Rinne test: BC > AC TREATMENT MEDICATIONS ▪ General ▫ Burow’s solution: topical drops application (buffered aluminum sulfate, acetic acid mixture) ▪ Bacterial ▫ Antipseudomonal otic drops/topical steroid drops/combination ▫ 3% acetic acid solution → acidify ear canal (bacteriostatic acidic pH) ▫ Systemic antibiotics (lymphadenopathy/ cellulitis) ▪ Fungal ▫ Topical antifungal preparation (e.g. gentian violet, boric acid) ▪ Chronic otitis externa (pruritus without obvious infection) ▫ Corticosteroid otic drops alone OTHER INTERVENTIONS ▪ General ▫ Clean ear under magnification → irrigation, suction, dry-swabbing ▪ Fungal ▫ Debridement Figure 73.1 An individual with otitis externa of the left ear. OSMOSIS.ORG 567
OTITIS MEDIA osms.it/otitis-media PATHOLOGY & CAUSES ▪ Inflammatory middle ear diseases TYPES Acute otitis media ▪ Acute middle ear compartment infection (< three weeks) ▪ Acute infection/allergies → nasopharyngeal mucous membrane inflammation → Eustachian tube dysfunction → secretion reflux/aspiration from nasopharynx to middle ear (normally sterile) → infection Otitis media with effusion ▪ Fluid presence in middle ear, with/without infection signs ▪ Eustachian tube dysfunction → trapped fixed gas volume in middle ear → surrounding tissue slowly absorbs gas → ↓ middle-ear pressure ▫ Sufficient ↓ middle-ear pressure → surrounding tissue fluid drawn into middle ear cavity → middle-ear effusion (transudate) ▪ Most common pediatric hearing loss cause Chronic suppurative otitis media ▪ Acute otitis media complication → chronic suppurative otitis media ▪ Perforated tympanic membrane with persistent drainage (> 6–12 weeks) ▪ Acute otitis media → prolonged inflammatory response → middle ear mucosal oedema; tympanic membrane ulceration, perforation → chronic middle ear, mastoid cavity inflammation → persistent discharge from middle ear through perforated tympanic membrane ▪ Persistent infection/inflammation → granulation tissue → polyps within middleear space → inflammation, ulceration, infection, granulation tissue formation cycle → eventual surrounding bony structure destruction 568 OSMOSIS.ORG CAUSES ▪ Bacteria ▫ S. pneumoniae, H. influenzae, M. catarrhalis, group A streptococcus, S. aureus) ▪ Virus ▫ Respiratory syncytial virus, influenza, parainfluenza, adenovirus) ▫ Often viral/bacterial coinfection RISK FACTORS Smoke, air-pollution exposure Immunosuppression Pacifier use; daycare Down syndrome Recent upper-respiratory tract viral infection ▪ Craniofacial malformation (cleft lip/palate, microcephaly) ▪ Cystic fibrosis ▪ ▪ ▪ ▪ ▪ Figure 73.2 A tympanic mebrane bulging as due to the accumulation of pus in the middle ear of an individual with otitis media.
Chapter 73 Ear Pathology COMPLICATIONS ▪ Tympanic membrane perforation, mastoiditis, cholesteatoma, bacterial meningitis, dural sinus thrombosis, conductive/sensorineural hearing loss SIGNS & SYMPTOMS ▪ Acute otitis media ▫ Otalgia, fever, conductive hearing loss (triad) ▫ Children: ear pulling, crying, poor sleep, irritability ▫ Crying → small blood vessel distension on tympanic membrane → mimics otitis media redness (confounds diagnosis) ▪ Otitis media with effusion ▫ Ear fullness, conductive hearing loss +/tinnitus, no pain/fever ▪ Chronic suppurative otitis media ▫ Perforated tympanic membrane; otorrhea; hearing loss; no pain/ discomfort; fever, vertigo, pain → danger signs (possible complications) DIAGNOSIS DIAGNOSTIC IMAGING CT scan/MRI ▪ Acute otitis media ▫ Severe cases with hearing loss/high fever) ▫ Excludes more serious complications (e.g. bony destruction/meningitis) Otoscopy ▪ Acute otitis media ▫ Tympanic membrane ↓ mobility, hyperemia, bulging membrane (pus behind tympanic membrane), landmark loss (malleus handle, long process not visible) ▪ Otitis media with effusion ▫ Amber/dull grey tympanic membrane discoloration; meniscus fluid level ↑ ↓, air bubbles behind tympanic membrane; air insufflation → immobile tympanic membrane ▪ Chronic suppurative otitis media ▫ Perforated tympanic membrane; otorrhea; visible granulation tissue (medial canal/middle-ear space); middle ear mucosa (through perforation) may be edematous, polypoid, pale, erythematous OTHER DIAGNOSTICS Otitis media with effusion ▪ Hearing tests for conductive hearing loss ▫ Weber test: sound lateralized to affected ear ▫ Rinne test: BC > AC ▪ Audiological investigation ▫ Flat audiogram, tympanogram TREATMENT MEDICATIONS ▪ Acute otitis media ▫ Analgesics ▫ Systemic antibiotics if severe/persistent (> three days) ▪ Otitis media with effusion ▫ Avoid antihistamines, decongestants → secretions thicken ▪ Chronic suppurative otitis media ▫ Corticosteroid drops → ↓ granulation tissue ▫ Antibiotics (topical/drops) ▫ Granulation tissue control: granulation tissue prevents affected-site topical medication penetration SURGERY ▪ Acute otitis media ▫ Frequent recurrence: tympanostomy tubes ▪ Otitis media with effusion ▫ Severe cases: tympanostomy tubes, myringotomy (tiny eardrum incision) +/ventilating-tube insertion OSMOSIS.ORG 569
OTHER INTERVENTIONS ▪ Otitis media with effusion ▫ Watchful waiting: 90% of children clear fluid in three months without intervention ▫ Minor cases: may resolve spontaneously; manual autoinflation (manually pinch nasal passage, close back of pharynx → forceful diaphragm contraction) ▪ Chronic suppurative otitis media ▫ Mechanical/irrigative debris clearing: aural toilet (mechanical removal of mucoid exudates, desquamated epithelium, associated debris prior to medication administration); aural irrigation (50% acetic acid/sterile water ear-rinse solution) PERFORATED EARDRUM osms.it/perforated-eardrum PATHOLOGY & CAUSES ▪ Tympanic membrane communication between middle ear, external environment CAUSES ▪ Otitis media ▪ Trauma ▪ Explosive/percussive force, exceptionally loud noise ▪ Iatrogenic, sudden pressure ↑ ↓ (with blocked Eustachian tubes) COMPLICATIONS ▪ Chronic infection → permanent hearing loss SIGNS & SYMPTOMS ▫ Hearing loss ▫ Tinnitus ▫ Ear-ache (infection association) ▫ Otorrhea ▫ Nausea/vomiting 570 OSMOSIS.ORG DIAGNOSIS DIAGNOSTIC IMAGING Otoscopy ▪ Perforation visualization OTHER DIAGNOSTICS ▪ Hearing tests: conductive hearing loss ▫ Weber test: sound lateralized to affected ear ▫ Rinne test: BC > AC ▪ Audiometry: conductive hearing loss TREATMENT MEDICATIONS ▪ Avoid otic drops containing gentamicin, neomycin sulfate, tobramycin ▫ Ototoxicity → permanent hearing loss ▪ Otorrhea control ▫ Topical: fluoroquinolone otic drops ▫ Systemic: antibiotics covering respiratory flora
Chapter 73 Ear Pathology SURGERY ▪ Tympanoplasty: surgical repair OTHER INTERVENTIONS ▪ Watchful waiting ▫ Perforations may heal in weeks/months Figure 73.3 A partial perforation of the ear drum. OSMOSIS.ORG 571

Osmosis High-Yield Notes

This Osmosis High-Yield Note provides an overview of Ear pathology essentials. All Osmosis Notes are clearly laid-out and contain striking images, tables, and diagrams to help visual learners understand complex topics quickly and efficiently. Find more information about Ear pathology by visiting the associated Learn Page.