CONDUCTIVE HEARING LOSS - Causes: cerumen impaction, middle ear fluid or infection, ↓ movement of small bones of ear or bony tumor of middle ear
OTOSCLEROSIS - Common cause of conductive hearing loss in adults, typically in 20s and 30s - Slight female predominance - Pathophysiology: abnormal remodeling of otic capsule, thought to be a possible autoimmune process in genetically susceptible individuals. The stapes footplate becomes fixed to the oval window, resulting in loss of its piston action. Sometimes referred to as otospongiosis as CT scan may show a lucent (as opposed to sclerotic) focus in the temporal bone near the oval window. - Low frequency hearing loss - Rx: hearing amplification or surgical stapedectomy
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SEROUS OTITIS MEDIA - Most common middle ear pathology in pts with AIDS - Due to auditory tube dysfunction arising from HIV LAD or obstructive lymphomas - Characterized by: middle ear effusion without acute infection - C/F: conductive hearing loss (most common feature) - Examination: dull, hypomobile tympanic membrane on pneumatic otoscopy SENSORINEURAL HEARING LOSS
PRESBYCUSIS - Disease of aging and usually first noticed in 6th decade of life. - Although dis. of aging but many factors have been shown to influence rate of hearing loss, including medicines, genetics, h/o infections, and exposure to loud noise - Begins with symmetrical, high frequency hearing impairment - Pts often complain of difficulty hearing in crowded or noisy environment, trouble hearing high-pitched noises or voices
MALIGNANT OTITIS EXTERNA - Typically seen in elderly diabetic pts (poorly controlled) or otherwise immunosuppressed pts - Most common cause: Pseudomonas aeruginosa - C/F: ear pain (typically worse at night), purulent ear drainage with sense of fullness not responsive to topical meds and conductive hearing loss, fever and elevated ESR - Otoscopy: Granulation tissue and edematous external auditory canal is characteristic - Progression osteomyelitis of skull base CN damage e.g. facial nerve. Or osteomyelitis of TMJ pain with chewing - Dx: CT or MRI to confirm diagnosis - Rx: systemic antibiotics effective against P. aeruginosa. IV ciprofloxacin—DOC for elderly pts. in patients with fluoroquinolone-resistant P aeruginosa, alternate therapies include anti-pseudomonal penicillins or cephalosporins such as piperacillin and ceftazidime. Failure to respond to antibiotics surgical debridement of necrotic tissue (not surgical excision) and biopsy to exclude malignancy