Auditory Disturbances PDF

EENT ( Ear Conditions ) Anatomy of the Ear External Ear Structures AURICLE/ PINNA EXTERNAL AUDITORY CANAL  Also known as the pinna Attached to side of head by skin Made mostly of cartilage Auricle Earlobe → fat and sub...

EENT ( Ear Conditions ) Anatomy of the Ear External Ear Structures AURICLE/ PINNA EXTERNAL AUDITORY CANAL  Also known as the pinna Attached to side of head by skin Made mostly of cartilage Auricle Earlobe → fat and subcutaneous tissue Collects sound waves and directs vibrations into external auditory canal External Auditory Canal 2 to 3 cm long Lateral third → elastic cartilaginous and dense fibrous framework w/c skin is attatched Medial 2/3 → bone line with thin skin Ends at the tympanic membrane  Hair Skin contains Sebaceous glands Ceruminous glands → Cerumen External Auditory Self cleaning Moves old skin cells and cerumen to outer part of ear Canal Anterior to external auditory canal → tempomandibular joint  Air filled cavity Middle ear Connected to nasopharynx by the Eustachian tube and continuous with the air filled cells in the adjacent mastoid portion of the temporal bone  Tympanic Membrane Middle Ear Eustachian Tube Structures Ossicles  1mm wide 35mm long Eustachian Tube Usually closed but opens by Connects middle action of tensor ear to veli palatini nasopharynx muscle Valsalva maneuver, yawns, swallows  Drains normal and abnormal secretions of the middle ear Eustachian Tube Equalizes pressure in the middle ear with that of the atmosphere  Eardrum 1cm in diameter Very thin Pearly grey and translucent Tympanic 3 layers of tissue Membrane Outer layer → continuous with skin of ear canal Middle layer → fibrous Inner layer → mucosal, continuous with lining of middle ear caviy  80% of tympanic membrane has all 3 layers → pars tensa 20% lacks middle layer → pars flaccida Absence of middle layer make pars flaccida Tympanic more vulnerable to pathologic disorders Membrane Protects middle ear Conducts sound vibrations from external canal to ossicles Sound presure is magnified 22x as a result of transmission from a larger area to smaller one Ossicles Three smallest bones in the body Held in place by joints, muscles, and ligaments Assist in transmission of sound Inner Ear House within temporal bone Structures Cochlea → organ for hearing Semicircular Canals → balance Cranial nerve VII (facial nerve) Cranial Nerve VIII (vestibulocochlear nerve) Parts Bony Labyrinth Membranous labyrinth  Housed inside the bony labyrinth Bathed in endolymph Composed of the Membranous Utricle → linear movement Saccule → linear movement Labyrinth Cochlear duct Semicircular canals → rotational movement Organ of corti → end organ for hearing Function of the Ears Functions Hearing Balance and Equilibrium AC > BC Assessment of the Ear  Inspection and Direct palpation Auricle and surrounding tissues Inspection of External Deformities, lesions, discharge Ear Size, symmetry, angle of attachment to the head Otoscopic Examination Inspect tympanic membrane and external auditory canal  Whisper Test Evaluation One ear at a time Examiner covers untested ear with palm and of Gross whispers into tested ear for 1-2 ft away. Patient with NORMAL acuity can correctly Auditory repeat whispered word Weber Test Acuity Rinne Test Weber and Rinne Test Diagnostic Evaluation Audiometry Detects hearing loss Single most important 2 kinds: 3 characteristics evaluated diagnostic instrument Pure tone audiometry Frequency Speech audiometry Pitch Intensity Typanogram AKA impedance audiometry Measures middle ear muscle reflex to sound stimulation and compliance of tympanic membrane by changing air pressure in sealed ear canal Compliance is impaired with middle ear disease  Use of endoscopes Middle Ear Minimally invasive Endoscopy Evaluate suspected perilymphatic fistula and new-onset hearing loss , anatomy of round window, and tympanic cavity Middle Ear Endoscopy Auditory Disturbances Otitis Externa  Inflammation of external auditory canal Causes: Water in ear canal (Swimmer’s ear) Trauma to skin of ear canal Otitis Systemic conditions (Vitamin deficiency and endocrine probelms) Externa Most frequently → Bacterial and Fungal infections Most common bacterial pathogens → S. Aureus and Pseudomonas species Most common fungus → Aspergillus (seen in normal and infected ears) Otitis Externa Can also be caused by: Psoriasis Eczema Seborrheic dermatitis Allergic reactions (hair spray, dye, lotions)  Pain Discharge from external auditory canal Aural tenderness Clinical Fever Manifestations Cellulitis Lymphadenopathy Pruritus Hearing loss or feeling of fullness  Erythema Edema Otoscopic exam Discharge → yellow or green and foul smelling Fungal infections → hair like black spores Medical Management OBJECTIVE: RELIEVE REDUCE SWELLING ERADICATE DISCOMFORT OF EAR CANAL INFECTION Medical Management Analgesics Antimicrobial or Antifungal medications Corticosteroids  Instruct patient DO NOT Clean external auditory canal with cotton tipped applicator Nursing AVOID events that can traumatize Management canal AVOID getting area wet PREVENTION of swimmers ear Malignant Otitis External  More serious, rare, external ear infection AKA Temporal bone osteomyelitis Progressive, debilitating, occasionally fatal infection of external auditory canal, surrounding tissue, and base of skull At risk populations: patients with immune system deficiencies (AIDS/HIV) Causative agent: psuedomonas aeruginosa Treatment: IV antibiotics, agressive wound care Antibiotics: combination antipseudomonal and aminoglycoside Otitis Media Acute Otitis Media Acute infection of the middle ear (less than 6 weeks) Can occur at any age, most commonly seen in children Risk Factors: Children: younger age, chronic URTI, infections, medical conditions (Trisomy 21, cystic fibrosis , cleft palate) SECOND HAND SMOKE EXPOSURE Pathogens: bacterial and viral Purulent exudate usuallly present in middle ear → conductive hearing loss  Vary with severity of infection Unilateral in adults w/ otalgia Pain → relieved after sponatenous perforation or theraputetic incision of tympanic membrane Clinical Other symptoms: Manifestations Drainage from ear Fever Hearing loss  Broad-spectrum antibiotics If with drainage → antibiotic otic preperation Medical Condition may become subacute with persistent Management purulent dischage Rarely causes hearing loss Involve mastoid, Secondary meningitis, brain abcess complications: Very rare Surgical Management Myringotomy/Tympanotomy Painless, less than 15 minutes, outpatient Done only if pain persists Allows drainage and for discharge to be analyzed Healing → 24 – 74 hours ONLY Serous Otitis Media Serous Otitis Media Middle ear effusion Presence of fluid WITHOUT evidence of active infection Results from negative pressure in middle ear caused by Eustachian tube obstruction Usually seen in patients post-radiation therapy or d/t barotrauma or eustachian tube dysfunction from concurrent URTI or allergy  Hearing loss Fullness in the ear or congestion Clinical Popping and crackling noises as Manifestations eustachian tube opens Otoscopy → dull tympanic membrane with air bubbles Audiogram → conductive hearing loss Management Medical intervention not If hearing loss is significant needed unless INFECTION → myringotomy occurs Valsalva maneuver → Corticosteroid → decrease cautiously, may perforate edema tympanic membrane or worsen pain Chronic Otitis Media  Recurrent AOM that causes irreversible tissue pathology CHRONIC Damage to tympanic membrane, OTITIS ossicles, involve mastoid MEDIA Rare in DEVELOPED COUNTRIES  May be minimal Varying degrees of hearing loss Persistent or intermittent, foul smelling otorrhea Clinical Manifestations NO PAIN unless with acute mastoiditis Otocope → perforation and cholesteatoma May cause mastoiditis → cholesteatoma  Cyst like lesion of external layer of tynmpanic membrane into middle ear Caused by CHRONIC RETRATION POCKET of tympanic membrane Cholesteatoma Skin forms sac that fills with dead skin cells and sebaceous materials Can attach to structures of middle ear, mastoid, or both Cholesteatoma May be asymptomatic Hearing loss Facial pain Paralysis Tinnitus Vertigo Audiometric testing → conductive or mixed hearing loss Medical Management Local treatment Systemic → suctioning Antibiotic drops antibiotics → under otoscopic or powder only in ACUTE guidance INFECTIONS  Tympanoplasty Surgical Ossiculoplasty Management Mastoidectomy Tympanoplasty Most common surigcal procedure or COM Surgical reconstruction of the tympanic membrane May require reconstruction of ossicles Purpose → reestablish middle ear function, close perforation, prevent recurrent infection, and improve hearing Done through trans canal approach or post auricular incision  Surgical reconstruction of ossicles Use of prostheses → teflon, Occiculoplasty stainless steel, or hypoxyapatite Greater the damage → low success rate to restore normal hearing  Objective: Remove cholesteatoma, gain access to diseased structure, create dry (noninfected) and healthy ear Ossicle may be reconstructed Mastoidectomy Extensive disease/damage may may be performed as part of a two-stage operation Post-auricular approach  1st stage → eliminate infection by removing mastoid air cels 2nd stage → check for recurrent or residual Mastoidectomy cholesteatoma , reconstruction of ossicles Success rate for correcting conductive hearing loss : 75% Facial nerve may be damage Otosclerosis Otosclerosis Involves stages Formation of new, abnormal spongy bone, especially around oval window, casuing dixation of stapes Sound transmission is prevented because stapes cannot vibrate Can progress to complete deafness Risk factors: Women Familial condition  Clinical Management May involve one or both ears Progressive conductive or mixed hearing loss Patient may or may not plamin of tinnitus Ostoscope → normal tympanic membrane Rinne Test → BC > AC Audiogram → confirms conductive or mixed hearing loss  Stapedectomy Removing the stapes superstructure and part of the foot plate and inserting tissue graft and suitable prosthesis Surgical Majority of patients experince resolution of conductive hearing loss Management Sodium fluoride give postop increases success rate and hearing ability Balance disturbance and virtigo may occur post op for serveral days LONG TERM Balance disturbances are RARE HOMEWORK 1 ACTIVITY 1