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• Ear


  Sense organ of hearing and equilibrium
• Ear

  • Consists of three distinct parts: external ear, middle ear, inner ear
• External Ear


  • Composed of the auricle (pinna) and the external auditory canal
• Auricle (pinna)

  Portion of the external ear visible without any tools, collects sound waves from the environment into the external auditory canal
• Cerumen


  Wax-like substance secreted by modified sweat glands in the external ear canal, keeps the tympanic membrane soft, has bacteriostatic properties, serves as a defense against foreign bodies
• Middle Ear (Tympanic Cavity)


  • Small, air-filled chamber in the temporal bone, contains the tympanic membrane (eardrum) and three auditory ossicles (malleus, incus, stapes)
• Tympanic membrane (eardrum)


  Translucent, pearly gray appearance, serves as a partition stretched across the inner end of the auditory canal, separating it from the middle ear
• Auditory ossicles


  Tiny bones (malleus, incus, stapes) responsible for transmitting sound waves from the eardrum to the inner ear through the oval window
• Eustachian tube


  Connects the middle ear to the nasopharynx, equalizes air pressure on both sides of the tympanic membrane
• Inner Ear (Labyrinth)


  • Fluid-filled, made up of bony-labyrinth and inner membranous labyrinth, contains the cochlea, vestibule, and semicircular canals
• Hearing


  1. Sound travels through air and bone conduction

  2. Sound waves enter external canal, pass through outer ear canal

  3. Vibrate tympanic membrane

  4. Vibrations transmitted through middle ear ossicular chain to oval window

  5. Cochlea receives sound vibration

  6. Nerve impulses from cochlea travel to auditory nerve (CN VIII) and cerebral cortex
• Disorders of the ear

  • Mechanical dysfunction (blockage by cerumen or foreign body)
  • Trauma (foreign bodies or noise exposure)
  • Neurological disorders (auditory nerve damage)
  • Acute illnesses (viral infection)
  • Toxic medications (ototoxicity, injury to auditory nerves from antibiotics)
• Ear Assessment


  • Collect subjective data, use otoscope, tuning fork, penlight, gloves
  • Patient position: sitting
  • Examination techniques: inspection and palpation
• Auricle/pinna


  Size, shape, symmetry, landmarks, position, color
• Ears are equal in size bilaterally (normally 4–10 cm), auricle aligns with corner of each eye within 10-degree angle of vertical position, color same as face, no moles, cysts, deformities or nodules, earlobes may be free, attached, or soldered
• Abnormal findings of auricle/pinna

  • Malaligned or low-set ears (genitourinary disorders, chromosomal defects)
  • Microtia (external ear and canal not fully developed)
  • Macrotia (excessive enlargement of external ear)
  • Enlarged preauricular and postauricular lymph nodes (infection)
  • Tophi (nontender, hard, cream-colored nodules on helix or antihelix, gout)
  • Ulcerated, crusted nodules that bleed (skin cancer)
• External auditory canal


  Inspect for size and discharge
• Meatus should not be swollen nor occluded, yellow cerumen is common, yellow/green foul-smelling discharge (otitis externa or foreign body), bloody/purulent discharge (otitis media with ruptured tympanic membrane), blood/watery drainage (CSF leak from skull trauma), impacted cerumen (conductive hearing loss)
• Palpation of external ear

  Texture, tenderness, skin lesions
• Smooth without lesions, soft and pliable, nontender with no nodules or swelling, if palpation increases pain then otitis externa is likely, if palpation does not influence pain then otitis media is likely, tenderness in mastoid area may indicate mastoiditis
• Auditory canal and eardrum inspection

  Examine deeper structures of external ear using penlight, grasp auricle upward and backward for adults, downward and backward for pediatrics 3 years and below
• Auditory canal has little cerumen, uniformly pink with tiny hair in outer third, dry cerumen is light brown to gray and flaky, moist cerumen is dark yellow or brown and sticky, reddened canal with discharge is a sign of inflammation or infection, impacted cerumen
• Whispered voice test


  Test one ear at a time, have patient cover opposite ear, stand 1-2 ft behind patient, whisper familiar 2-syllable words, note patient's ability to hear, increase intensity if needed, have patient repeat words
• Normal: patient correctly repeats whispered words in each ear at 1-2 ft, Abnormal: inability to repeat words (low-tone frequency loss or hearing loss)
• Weber test


  Tap tuning fork on palm, place vibrating tuning fork on patient's forehead or top of head, note lateralization of sound
• Normal: vibrations heard equally on both ears, Negative lateralization, Abnormal: lateralization of vibrations (conductive loss = lateralization to poor ear, sensorineural loss = lateralization to good ear)
• Rinne test


  Strike/tap tuning fork, place on mastoid process, note time until patient can no longer hear, immediately bring in front of ear, note time until no longer heard
• Romberg test


  Have patient stand with feet together, eyes open then closed, note ability to maintain balance/upright posture
• Normal Romberg: patient maintains balance with minimal sway, Abnormal Romberg: patient loses balance, suggests inner ear disorder, cerebellar damage, or intoxication