A Stable Life, Despite Persistent Dizziness
On the subway, children twirl themselves around the poles in the cars until they are so dizzy I’m ready to catch them. The young seem to delight in making the world spin out of control for a few moments, causing them to flop about like drunks.
But when dizziness, vertigo or loss of balance is neither self-imposed nor short lived, it is anything but fun. It can throw one’s whole life out of kilter, literally and figuratively.
This is what befell Cheryl Schiltz in 1997, when long treatment with the antibiotic gentamicin permanently damaged the vestibular apparatus in her inner ear. For three years, said Ms. Schiltz, of Madison, Wis., her world seemed to be made of Jell-O. Lacking a sense of balance, she wobbled with every step, and everything she looked at jiggled and tilted.
Unable to work, Ms. Schiltz became increasingly isolated and struggled to perform the simplest household tasks.
Lisa Haven, executive director of the Vestibular Disorders Association, reports that “the risk of falling is two to three times greater in people with chronic imbalance or dizziness.” Nearly 9 percent of Americans 65 and older have balance problems, the prevalence of which is likely to increase as the 78 million baby boomers age.
Four Types of Dizziness
The job of the vestibular system is to integrate sensory stimuli and movement for the brain and keep objects in visual focus as the body moves. When the head moves, signals are sent to the inner ear, an organ consisting of three semicircular canals surrounded by fluid. It in turn sends movement information to the vestibular nerve, which carries it to the brainstem and cerebellum, which control balance and posture and coordinate movement. Disruption of any part of the system can result in dizziness.
These are four types of dizziness, all of which are more common with increasing age:
¶Faintness, the feeling of being about to black out when upright. This can result from dehydration, abnormal heart rhythms, overmedication with blood pressure drugs and disorders of the autonomic nervous system.
¶Loss of balance, feeling unsteady and about to fall even though muscle strength is normal. This can be caused by disorders of the inner ear; the cerebellum because of stroke or chronic alcoholism; or the basal ganglia, because of Parkinson’s disease, for example. It can also result from overmedication with drugs like sedatives and anticonvulsants, vision disturbances and neuropathy or spinal cord disease that causes a loss of position sense in the legs.
¶Vertigo, a false sense that the person or the surroundings are moving or spinning. This can result from motion sickness, Ménière’s disease, middle-ear infections, migraines, multiple sclerosis, damage to the vestibular nerve and reduced blood flow to the brain after a stroke or transient ischemic attack. In the most common form, benign paroxysmal positional vertigo, sudden head movements cause a sensation of motion.
¶Vague lightheadedness, a feeling of giddiness or detachment from the world that can be caused by a panic attack, depression, anxiety disorders or hyperventilation.
What to Tell the Doctor
About 40 percent of people experience at least one of these forms of dizziness at some time during their lives. When dizziness persists, medical care is essential, and so is the ability to provide a detailed description of the symptoms and what provokes them.
What does the dizziness feel like — faintness, loss of balance, lightheadedness, a sensation that you or your surroundings are spinning or moving? When did the symptoms begin? How long do they last? What provokes or relieves them? What other symptoms like headache, ringing in the ears, impaired vision, difficulty walking, weakness or hearing loss accompany the dizziness?
Diagnostic tests may include trying to reproduce the symptoms. For example, by rapidly standing and sitting, standing after lying down or lying on a tilt table while changes in blood pressure are measured.
The doctor may test heart function with an electrocardiogram or an echocardiogram, an exercise stress test or a Holter monitor to detect abnormal rhythms.
Vision tests may be performed, along with tests to evaluate balance and gait and C.T. or M.R.I. scans of the head, including noninvasive tests that check for narrowed or blocked arteries to the brain.
If no physical explanation for dizziness is found, the patient may be checked for psychological disorders like depression, panic attacks or dissociation from the world.
Treatment will depend on the cause of the dizziness. For example, for benign paroxysmal positional vertigo, a simple head-turning maneuver that repositions crystals in the inner ear may bring lasting relief. If ministrokes are the cause, the treatment may involve anticlotting drugs or opening a blocked artery with a stent. If medication is the problem, adjusting the dose or changing the drug can relieve dizziness.
If dizziness persists despite treatment, lifestyle adjustments can help like avoiding sudden movements, keeping often-used items within easy reach, standing up slowly and clenching hands and flexing feet before standing. Physical therapy can help, as can exercises that strengthen muscles and that combine eye, head and body movements.
Ms. Schiltz, whose vestibular system was damaged a decade ago, said she was told that nothing could be done about it. Nothing, that is, until she became the first patient to be treated with a device called a BrainPort invented by the late Dr. Paul Bach-y-Rita, a neurobiologist and rehabilitation medicine specialist, and his colleagues at the University of Wisconsin.
The device takes advantage of the acute sensitivity of the tongue and sends balance signals directly to the brain from the tongue, bypassing the ear’s vestibular apparatus. At first, she used it a few minutes at a time, but soon found longer use kept her in balance for hours, then days, then weeks and months.
Eventually, all that was needed was 20 minutes twice a day to train her brain, and she now uses it just occasionally.
She is among more than 100 study participants who have used the BrainPort, including patients with multiple sclerosis, Parkinson’s disease and stroke. The device is available commercially in Canada and is awaiting approval by the Food and Drug Administration in the United States.
Dr. Norman Doidge of the research faculty at the Columbia University Psychoanalytic Center and the University of Toronto describes Ms. Schiltz’s dramatic recovery in his new book about the plasticity of the brain, “The Brain That Changes Itself.” (Her case was also described in Science Times in November 2004.) With her sense of balance intact, Ms. Schiltz was able to return to school and on Dec. 20 received a degree in rehabilitation psychology.
“I feel like a restored, even enhanced, person,” she said in an interview. “I’m living proof that the brain can be retrained. My goal now is to help people with acquired disabilities gain increased independence.”
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