“When you have it, it is devastating,” said Lisa Farrell, PT, PhD, ATC, a vestibular rehab specialist in practice at OrthoSport near Fort Lauderdale, Fla. Patients with MdDS experience a persistent rocking, swaying or bobbing sensation, after spending at least four hours on a cruise, airplane, train or car ride.
“They are fine during the voyage, but when they disembark, almost immediately, they will have a sensation that they are still on the boat,” Farrell said. People often experience a feeling of needing to get their land legs, which usually lasts only a day or so. But with MdDS, the sensations persist.
Patients sometimes report the symptoms improve while they are moving, such as when riding in a car or walking. But in other patients, the disequilibrium is so severe they have difficulty ambulating. “If it lasts more than a year, they have less of a chance of the syndrome going away, and they can have it for years,” Farrell said.
On dry land
However, help is available. “Physical therapy is very effective for mal de debarquement, but if a doctor doesn’t recognize the person has the condition, they don’t send them to the right PT,” said Linda Csiza, PT, DSc, NCS, assistant clinical professor of physical therapy at Texas Woman’s University in Dallas.
Clinical testing is called for, and diagnosis depends on case history and the ruling out of other vestibular conditions, which takes time. “That leaves people feeling helpless,” said Linda McManus, PhD, a member of the MdDS Balance Disorder Foundation board of directors who suffers from the condition. “That is a tremendous challenge for the patient.”
More women than men develop MdDS, and it typically occurs in middle age. The number of people who suffer from MdDS is unknown. McManus and Csiza suspect the disorder is more common than acknowledged.
MdDS patients often experience anxiety or depression, which may be because the physiologic fear-anxiety pathway runs along the vestibular pathway in the brain stem. “Someone who has a [vestibular] pathway that fires aberrantly — someone with mal de debarquement — can get their fear-anxiety pathway flared up,” Csiza said. “Now, you have an abnormal fear-anxiety response. The people hardest to treat are those that have the anxiety component as well.”
Farrell said she does not believe MdDS is an emotional disorder, but in patients with anxiety, the symptoms may worsen. She frequently will refer patients to psychologists for cognitive behavioral training, to learn how to minimize fears and anxieties that result from MdDS.
Setting a course
While the etiology of MdDS has yet to be discovered, several theories exist. Some theorize MdDS may be a variant of migraine, or it might be maladjustment of the autolytic part of the vestibular system. Csiza said the autolytic system may stop firing while the person is on the ship, but it fails to return to normal firing on land whenever there is a change in acceleration, deceleration or tilting. Then it starts firing all of the time. When MdDS sufferers rock or sway, they may be trying to make the signals make sense to the brain, Csiza said.
The MdDS Balance Disorder Foundation is funding research to identify the area of the brain affected and develop treatments using transcranial magnetic stimulation. Brian C. Clark, PhD, director of the Ohio Musculoskeletal and Neurological Institute at Ohio University in Athens, is using TMS in 10 MdDS patients and 10 healthy matched controls, in hopes of discovering how the sufferers’ brains differ. “It’s likely a failure of the nervous system to re-adapt to its more stable conditions, but what is causing it not to re-adapt is still the million-dollar question,” Clark said.
Yoon-Hee Cha, MD, an assistant professor in residence at the University of California, Los Angeles Department of Neurology, is conducting functional neuroimaging, looking at brain metabolism with fluorodeoxyglucose positron emission tomography in 20 patients with MdDS and a matched control group, and has discovered differences. “I think it will help doctors and people who take care of patients with MdDS [to know] there is a metabolic change in patients, that they are not making it up,” Cha said.
Cha also is using functional MRI to assess brain perfusion with visual motion processing in 20 MdDS patients who complain of rocking with visual motion. Cha began a phase one study to see whether TMS will alter the rocking sensation, and has found some short-term improvement. She plans to conduct a phase two study, administering TMS daily for five days to see whether that will result in long-term symptom relief or any imaging changes occur.
Providing an anchor
Although no data exists to support any treatment yet, various therapies may help keep symptoms under control so patients can function in their daily lives. “We train people how to move and respond appropriately to the situation that is occurring,” Csiza said. That includes advising patients to settle, to feel the stillness and convince the brain they are still. She then performs traditional vestibular therapy exercises. For example, she has patients stand with their feet together, focus on an object, and turn their heads side to side to use the vestibular-ocular reflex and give a stable gaze. This may cause slight dizziness, but over time patients are able to do it without abnormal sensations. She then advances to more challenging exercises.
Farrell focuses on education and the mechanisms of orientation — vision, touch and the inner ear vestibular system — relaxation, and coping skills. She teaches patients to rely more on touch or pressure than input from the inner ear. She may have patients stand on a cushion, which brings on the symptoms, followed by centering or recognizing through other senses that they are on a solid surface.
Although Farrell acknowledges only about half of her patients benefit from vestibular rehab, she said patients report the education, relaxation techniques and coping strategies helpful.
“Getting to the right person as quickly as they can makes a big difference,” Csiza said. “And the right person is a physical therapist.”
(Source: http://www.todayinpt.com/)
No comments:
Post a Comment