Dizziness
John R. Collier, Jr., MD
In order to keep our balance, we use our visual, vestibular (inner ear), and proprioreceptive (touch) sensory systems. The brain then interprets and coordinates the information from these senses. To move about successfully two of these three sensory systems, as well as the brain and muscle system have to be functioning well. The need for two of these sensory systems working well is why it is so important for people with balance problems having a light on when they get up at night.
Dizziness is a sensation of not being able to keep one’s balance. This sensation will be described very differently by different people. Sometimes the sensation is of being light headed. Sometimes it is a spinning sensation (vertigo). Sometimes it is hard to describe. The sensation of dizziness is usually caused by problems with the inner ear or the brain. Heart or blood pressure problems can cause dizziness by reducing blood flow to the brain.
One common cause of dizziness is Benign Postional Vertigo (BPV). Our inner ears keep balance two ways. Small crystals (otoliths) in one part of the inner ear move in response to gravity. Like a cat thrown in the air, we too know which way is down. The inner ear also has other parts called the semicircular canals which respond to movement. In BPV otliths come loose and fall into the posterior semicircular canal. This distorts the signal the inner ear sends to the brain. The typical symptom of BPV is dizziness with sudden turning movements, or with lying back and turning to one side. An office test called the Dix-Hallpike will usually detect BPV, and a series of positioning exercises will relieve the symptoms 80% of the time.
Another relatively frequent cause of dizziness is Meniere’s syndrome. The cause is unknown, but most researchers feel there is swelling in part of the inner ear. Someone with classic symptoms of Meniere’s will have spells of incapacitating dizziness associated with pressure, ringing, and hearing loss in the ear. Fortunately, most people don’t have symptoms this severe, and will respond to strict control of salt intake in their diet. However, severe cases may require one of various means of destroying the inner ear to relieve the symptoms.
Although, very rare, another cause of dizziness is an acoustic neuroma. This is a slow growing benign tumor on the nerve between the inner ear and the brain. This diagnosis has to be considered and tested for in any patient who has had unexplained dizziness or one sided hearing loss for an extended period of time.
Many of us have had the experience of waking up and being dizzy. This usually goes a way in a few days, though it sometimes will last much longer. This is typically called an inner ear infection. Other names include Viral Labyrinthitis or Vestibular Neuronitis. Though there are probably many causes, it is most likely caused by a viral infection (antibiotics will not help). Medicines like meclizine are given to help symptoms, but like the common cold, there is no really effective treatment, and the symptoms will pass with time.
Unfortunately, many people with dizziness have chronic medical conditions such as atherosclerosis which can affect the brain or the inner ear. These changes are often irreversible but with new advances in vestibular rehabilitation and physical therapy many patients can now be successfully treated.
Though most cases of dizziness are not emergencies, some can be. Dizziness associated with infected or draining ears, severe hearing loss, or loss of consciousness, usually requires immediate medical attention.