Outline of Causes of Dizziness, Imbalance and Hearing Disorders.

Timothy C. Hain, MD • Page last modified: February 24, 2021

Definitions:

• Dizziness:
  • Vertigo (spinning or other illusion of movement such as tilting, floating, or impulsion). Vertigo is generally caused by an inner ear disturbance, but can also be cause by a central (brain) disturbance. 
  • Lightheaded sensation, impending faint. Lightheadedness is generally caused by low blood pressure, and may be associated with orthostatic hypotension or syncope.
  • Confusion. Generally caused by metabolic (blood chemistry) disturbances.
  • Spatial discomfort. This category encompasses all types of dizziness not specifically covered by the above, and is especially applicable to dizziness caused by psychiatric disorders.
• Imbalance: Unsteadiness leading to increased risk of fall. Imbalance commonly accompanies dizziness, but can also be independant. There are a large number of individual causes of imbalance.
• Drop attack: unprovoked fall without loss of consiousness
• Hearing disorder: Hearing disorders commonly accompany dizziness caused by ear disorders. They are also common in individuals over the age of 50, with any type of dizziness.

Overview: These words are often used in a general way and cover a large number of categories of disease. One must be more specific in order to narrow down to a smaller potential subset of disorders.

Causes of Dizziness.

• Otologic (inner ear related, about 50% of all dizziness)
  • BPPV (benign paroxysmal positional vertigo, about 50% of inner ear related)
  • Menieres disease (about 18% of inner ear)
  • Vestibular neuritis and labyrinthitis (about 14% of inner ear)
  • Perilymph Fistula (rare)
  • Bilateral vestibular loss (rare)
  • Acoustic neuroma (rare)
  • Many other rare disorders
• Central or Neurologic (brain related, 5% of dizziness in general)
  • Stroke, Migraine and other disturbances of circulation to the brain (50% of neurologic dizziness)
  • Seizure (5% of the 5% -- i.e. very rare)
  • MS and other disorders of the white matter (1%)
  • Cerebellar degeneration, Chiari malformation, and other disorders of the cerebellum (about 2%)
  • Mal de Debarquement syndrome (rare)
  • Others (all unusual)
• Medical  (5-10%)
  • low blood pressure including syncope, orthostatic hypotension, cardiac arrythmia
  • medication side effect
• Psychological (15%)
  • anxiety and panic disorder
  • malingering
  • phobia
  • somatization syndrome
  • Chronic Subjective Dizziness (CSD)
  • Phobic positional vertigo
• Unknown causes or diagnoses so vague as to be meaningless (25%)
  • Multisensory disequilibrium of the elderly
  • post-traumatic dizziness
  • psychogenic dizziness (when diagnosis is simply one of exclusion)

Overview: The proportion of dizziness attributed to these categories varies considerably, but roughly 50% of all dizziness is caused by inner ear disturbances, about 5% by medical and neurological problems each, about 15% by psychological disturbances, and the remainder of patients (about 25%) the diagnosis is essentially unknown.

Causes of Imbalance

• Sensory disturbances (loss of position sense, vestibular sense, visual sensation, or a combination of all three). Any source of dizziness can cause imbalance.
  • B12 deficiency (common)
  • Peripheral neuropathy (common)
  • Bilateral vestibular loss (rare)
  • Dysequilibrium of blind persons
• Central,  brain disturbances, including the same causes of central dizziness listed above, plus
  • Migraine (common)
  • Multiple small strokes (common)
  • Cerebellar degeneration, Chiari malformation, and other disorders of the cerebellum (moderately common)
  • Parkinsonism and related disorders of the basal ganglia (moderately common)
• Hydrocephalus or CSF leak (rare)
• Mal de Debarquement syndrome (rare)
• MS and other disorders of the white matter (rare)
• Remote effect of cancer (rare)
• oculopalatal myoclonus (rare)
• orthostatic tremor (extremely rare)
• Peripheral (weakness such as caused by muscle disease), or spinal cord disorders.
  • These are common disorders but generally other symptoms than imbalance dominate the picture
  • Spinal cord compression (uncommon).
    • Tinnitus and dizziness can be associated with neck disease causing some diagnostic confusion

Overview: In dizzy patients, most imbalance is caused by inner ear disturbances. When dizziness is not present, most imbalance is central.  In older patients, multisensory disturbances are the most common. In younger patients, central problems are more common.

Causes of Hearing Disturbances

• Conductive type (mechanical)
  • ear wax
  • ear drum perforation
  • middle ear infection or fluid
  • inner ear bone (ossicle) disturbance, such as otosclerosis
• Sensorineural type (hair cells or nerve)
  • presybyacusis (age related hearing loss)
  • noise trauma
  • acoustic neuroma (rare)
  • radiation (rare)
  • congenital (rare)
  • Infection due to syphilis (very rare)
• Central type (brain)
  • brainstem
  • auditory cortex
• Psychological (malingering)
• Mechanism usually unclear
  • Sudden hearing loss

Overview: The great majority of hearing disturbances are sensorineural, either associated with aging or noise exposure. Conductive hearing losses can generally be fixed by surgery. Central hearing losses are very rare. Psychological hearing losses are also very uncommon.

References:

• Hain TC, Herdman SJ. Dizziness in the Elderly. (Ed Sage JI, Mark MH) Practical Neurology of the Elderly. Marcel Dekker Pub, New York, NY 1996.
• Hain TC. Vertigo and Disequilibrium. In: Current Treatment in Neurologic Disease, 5th edn, Eds. R. Johnson and J. Griffin, p 8-12, 1997, also In: Current Therapy in Adult Medicine, 4th edn, Kassirir JP and Greene HL, Mosby, p 1358-1361, 1997.
• Hain TC. Approach to the Vertigo Patient In Practical Neurology, Jose Biller (Editor), 1997 (as well as several subsequent editions).