by Sheri B. Doniger, DDS
The camera pans down the long, square stairway. From Jimmy Stewart's visual perspective, the camera goes out of focus and elicits a double vision effect. He is trying to rescue Kim Novak in the clock tower, but his dizziness gets in the way. As the camera emulates his spinning surroundings, the audience also experiences a touch of vertigo.
Ever get that dizzy, disoriented, or light-headed feeling? People with vertigo or other balance disorders may experience it on a daily basis. The false sense of movement, manifesting itself as a spinning feeling similar to the one felt after riding the "tilt-a-whirl," may occur. The world may appear to spin, or the one suffering may feel as if he or she is spinning. A sense of falling, visual blurring, and disorientation may occur. These sensations may last for a short while or for months, and may be occasionally accompanied by nausea and vomiting. After time, the nervous system usually adapts to the episodes, which allows the symptoms to decrease over time.
"Balance disorders," according to the National Institute of Health, affects more than 90 million Americans, or 42 percent of the population, and they visit their health practitioners regarding dizziness. Occurrences increase with age, and dizziness is one of the most common reasons patients over the age of 75 see a physician. As dental practitioners, we may be the first to notice or hear about symptoms from our patients.
The inner ear is the main organ that controls balance. It consists of two parts: the labyrinth and the otolithic organs. Along with other proprioceptive senses, such as the nervous, visual, and muscular systems, it maintains balance and position. The labyrinth is composed of three fluid filled semicircular canals. As we move, the fluid moves and signals the brain "where we are in space," and detects the speed and rotation of our head movement. The otolithic organs are the utricle and the saccule, which detect linear movement. All three of these organs contain tiny hair cells that constantly monitor position with the displacement of the fibers. Small calcium carbonate stones called otoconia are located in the otolithic organs and displace when the head is bent, then signal the position to the brain.
The etiology of balance disorders may be central, peripheral, systemic, or vascular. Some are idiopathic. Several medical conditions may elicit this spinning, dizzy feeling. Benign positional vertigo, vestibular neuronitis, and Meniere's disease are three common balance disorders. Other causes of dizziness and imbalance may be a stroke, brain tumors, multiple sclerosis, Parkinson's disease, or cardiac disorders. These differ from the first three in that they may have additional symptoms such as slurred speech, weakness, numbness, or double vision.
Bacterial or viral infections that affect the inner ear or other areas of the body, as well as head injuries, may also cause balance disorders. Vertigo may also be brought on by rapid changes in motion, such as a roller coaster or other spinning ride, air turbulence in an airplane, or the movement of a car or boat.
Dizziness, on its own, may also be caused by presyncope, orthostatic hypotension, atherosclerosis, arrhythmia, or other cardiomyopathies. Additionally, dizziness may be due to anxiety or hyperventilation. Balance may be affected by inner ear problems, a peripheral neuropathy, age, joint and muscular inflammation caused by arthritis, diabetes, and medication side effects. Migraine sufferers may exhibit dizziness either before or during their episodes. Long-term use of certain antibiotics, such as streptomycin, gentamicin and tobramycin, may also cause damage to the inner ear and elicit dizziness.
Benign paroxysmal positional vertigo (or BPPV) is caused by the movement of the calcium otolith or debris inside the inner ear into an incorrect space, affecting balance. Normally, these calcium stones detect gravity, not head position. With BPPV, the reverse occurs. The actual etiology is unknown, but may occur due to a head injury, usually in patients under the age of 50. An infection may precipitate the event. A vertigo incident may last from 10 to 20 seconds and is more common after the sixth decade of life.
Although BPPV may disappear within two to three months without treatment, therapy may be necessary. The "Epley maneuver" is a series of head and body movements used to reposition the calcium particles in the ear. Patients are also advised to keep their heads above their hearts for two to three days post incident. This step in the therapy obviously impacts dental care.
Acute vestibular neuronitis is an infection of the vestibular nerve of the inner ear. This is usually viral in origin, can occur in all patients of all ages and cause sudden, recurrent periods of vertigo that may last for days or weeks. Feelings of spinning, nausea and vomiting may occur in addition to permanent damage to the balance system on the affected side. The symptoms are usually worse very early, then subside with time. Symptoms usually clear up on their own, but intervention may be necessary.
Medical management includes drugs such as meclizine (Antivert) or promethazine (Phenergan). Anti nausea drugs such as prochlorperazine (Compazine) can also be used. To decrease the inflammation of the nerve inside the inner ear, corticosteroids may be prescribed.
Patients should minimize head movements as much as possible. Training exercises are used to correct the loss of balance and promote compensation for the patient.
Meniere's disease is characterized by long-lasting episodes of vertigo due to fluid building up in the inner ear. These patients may experience tinnitus and hearing loss, especially to low frequency sounds, in addition to the vertigo or dizziness symptoms. The etiology is not clear, but early ear infections may be the cause and usually only one ear is affected.
Medical management is similar to vestibular neuronitis. Additional therapies may include dietary changes such as limiting the amount of caffeine, alcohol and sodium, and avoiding nicotine. Amino glycoside antibiotics are also administered, both topically (gentamicin) and systemically (streptomycin), although the former may cause hearing loss. Surgical intervention may be necessary if the patient does not respond to these forms of medical management.
Patients with vertigo are advised to avoid dental treatments during episodes, as our chair position may stimulate an occurrence. One of my patients experienced her first serious episode in my dental chair. As the chair was automatically positioned, she became so dizzy that she couldn't move for several minutes. She felt her head was swimming. She had to be driven home, then taken to the emergency room for treatment. The cause of her initial event was unknown, but she has been advised not to lie down completely, either in her bed or the dental chair. She has to elevate her head with a pillow at night.
The good news is that due to our complex vestibular system, dizziness will usually correct itself or the body will compensate with the interaction of the brain, musculoskeletal, and nervous system. We still need to be aware of patients who may experience imbalance episodes. As we review the medical history of our patients, we become attuned to the signs and symptoms of these balance disorders.
A medical referral should be sought if the patient experiences any sudden or unexplained dizziness or loss of balance. Altering our treatment time and chair position may be necessary to assure patient comfort. After all, it is a question of maintaining balance in our patients' lives.
Sheri B. Doniger, DDS, has been in the private practice of family and preventive dentistry for more than 20 years.A dental hygiene graduate of Loyola University, prior to receiving her dental degree, her current passion is focusing on women's health and well-being issues.She may be contacted at (847) 677-1101 or [email protected].Resources:
www.nidcd.nih.gov (National Institute on Deafness and Other Communication Diseases) Balance Disorders, accessed 4/10/03
www.vestibular.org (Vestibular Disorders Association) Vestibular Disorders: An Overview Accessed 4/10/03