03. Hearing Loss

Resident Editor: Mia Williams, MD

Faculty Editor:  Chase Heaton, MD

BOTTOM LINE

✔ For all cases of hearing loss, take a thorough H+P to differentiate between conductive vs sensorineural hearing loss.

✔ For sudden sensorineural hearing loss, high-dose steroids are recommended with urgent ENT referral.

Background

  • The WHO estimates that hearing loss affects 538 million people worldwide. 
  • The signs and symptoms of hearing loss may be subtle, so heightened suspicion in patients with risk factors is warranted. 
     

Signs and Symptoms

  • Functional or cognitive decline
  • Depression or anxiety, social withdrawal, poor word discrimination
  • Patients with tinnitus often have concomitant hearing loss

Differential Diagnosis

Conductive hearing loss: Middle + Outer ear causes

Sensorineural hearing loss: Inner ear +Auditory nerve

Middle ear:

  • Temporal bone trauma
  • TM perforation: traumatic, following otitis media (OM)
  • OM with effusion: children, recent URI
  • Serous OM: Eustachian tube dysfunction, clear fluid, and bubbles behind the TM 
  • Cholesteatoma
  • Sudden (clinical emergency): rule out HSV (vesicles), tumor, autoimmune, microvascular event
  • Meniere’s disease: fluctuating, ear fullness, and vertigo
  • Presbycusis (old age): slowly progressive
  • Ototoxic drugs: aminoglycosides, vancomycin, erythromycin, loop diuretics, antimalarials, cisplatin, sildenafil, cocaine
  • Cerebrovascular ischemia
  • Multiple sclerosis 
  • Meningitis
  • Acoustic neuroma and other skull base tumors

 

Outer ear:

  • Otitis externa (OE): swollen canal, painful canal, draining ear
  • Cerumen impaction: VERY unlikely to cause significant HL
  • Trauma
  • Squamous cell carcinoma
  • Exostosis: commonly known as surfer’s ear; cold water exposure causes abnormal bone growth within the ear canal. 
  • Osteoma: benign bone tumor

Evaluation

  • History
    • Time course: sudden, progressive, after trauma or recent URI
      • If pre-existing did the loss occur prelingually, pre or post-school, and vocation
      • Ask how (if at all) impacts lifestyle and preferred method of communication
    • Laterality
    • Associated symptoms
      • Ear pain: TM perforation, OM, OE
      • Drainage: OE, TM perforation resulting from bad OM, middle ear tumors
      • Vertigo: Meniere’s, acoustic nerve and inner ear tumors
      • Tinnitus: presbycusis
    • History of prior infections, surgery, family history of hearing loss
    • Disproportionately affected by depression, anxiety, decreased screening, and decreased health literacy.
  • Examination
    • Physical exam of the auricle and external auditory canal to identify evidence of blockage.
    • Otoscopy/Pneumoscopy – normal exam: flat, pearly gray TM without erythema or middle ear fluid noted.  Decreased mobility of TM on pneumotoscopy if middle ear effusion is present.
    • Tuning Fork (512 Hz, not the neurology tuning fork)
      • Weber (midline forehead, nose, or front incisors): sound lateralizes to “good” ear in sensorineural hearing loss; sound lateralizes toward “bad” ear in conductive hearing loss.
      • Rinne: air conduction (fork held in front of the ear) should be louder than bone conduction (tuning fork pressed on the mastoid bone)
        • Bone conduction>air conduction = any cause of mechanical or conductive hearing loss (wax, OE, TM perforation, OM, etc).
  • Diagnostic tests
    • Audiogram with ENT referral
    • Imaging
      • CT for bone conduction abnormalities
      • MRI if concern for vestibular tumor

Treatment

Conductive hearing loss: Middle + Outer ear causes

Sensorineural hearing loss: Inner ear +Auditory nerve
  • OM with signs of infection: amoxicillin 500mg PO BID x5-7 days vs azithromycin 500mgx1->250 mg x5 days 
  • If no systemic signs of illness, do not need to treat
  • Serous OM: consider 1g amoxicillin, nasal sprays (steroid and NS) for Eustachian tube dysfunction.  If unilateral and/or persistent, needs ENT evaluation.
  • OE: clean out the external canal. If mild Acetic acid 2% and hydrocortisone 1% otic solution; If severe Cipro 0.3% + steroid BID with STRICT dry ear precautions, close f/u especially if DM or immunocompromised.  If you can’t see the TM, may need a wick (start drops with referral).  If refractory to treatment, refer to ENT.
  • Cerumen impaction: nursing can remove.  If unsuccessful can be done under a microscope in an ENT clinic to prevent canal trauma and infection.  Prescribe debrox (carbamide peroxide): 5-10 drops in each ear BID, have the patient lay on the side so drops stay in the canal for ~1 minute. Do not do irrigation in the ears with a tympanic perforation or in diabetic patients.
  • Sudden (clinical emergency): high dose corticosteroids (oral and/or intratympanic installation) no evidence for benefit of antivirals. The immediate audiogram and ENT referral (both within 1-2 days). Page ENT/OHNS resident.
  • Meniere disease: low salt diet, diuretics, ENT referral with a serial audiogram
  • Presbycusis: audiogram for confirmation, hearing aid referral. 

When to Refer

  • For all sudden hearing loss
  • Any lesion that is concerning for a tumor/cancer of the ear or external auditory canal
  • Hearing loss associated with facial weakness
  • Unilateral hearing loss that requires further evaluation (as for acoustic neuroma)
  • Hearing loss associated with treatment-refractory infections
  • Hearing loss associated with dizziness

References:

Rosenfeld RM, Singer M. Systematic review of topical antimicrobial therapy for acute otitis externa. Otolaryngol Head Neck Surg. 2007;134:S24.

Stachler R, Sujana C. Clinical Practice Guideline Sudden Hearing Loss. Otolaryngology Head Neck Surgery March 2012: v146 S1-35. 

Takata GS, Chan LS. Evidence assessment of management of acute otitis media. Pediatrics. 2001; 108(2):239. 

CDC Health Disparities and Inequalities Report — United States, 2013. MMWR. Supplement / Vol. 62 / No. 3. 2013.

Uy J, Forciea MA. In the clinic. Hearing loss. Ann Intern Med 2013.