Mal de debarquement
Mal de debarquement (or Mal de débarquement) syndrome (MdDS, or common name disembarkment syndrome) is a rare neurological condition usually occurring after a cruise, aircraft flight, or other sustained motion event. The phrase "mal de débarquement" is French for "Sickness from Disembarkation". MdDS is typically diagnosed by a Neurologist or an Ear Nose & Throat Specialist when a person reports a persistent rocking, swaying, or bobbing feeling (though they are not necessarily rocking). This usually follows a cruise or other motion experience. Because most vestibule testing proves to be negative, doctors may be baffled as they attempt to diagnose this rare neurological syndrome. A major diagnostic indicator is that most patients feel better while driving or riding in a car or while in passive motion. The syndrome has recently received increased attention due to the number of people presenting with the condition and more scientific research has commenced now for a number of years to determine what triggers MdDs and how to cure it.
Symptoms
Symptoms most frequently reported include a persistent sensation of motion usually described as rocking, swaying, or bobbing; difficulty maintaining balance, will be more susceptible to falls, so care should be taken with sudden movements or turns; extreme chronic fatigue; can become fatigued quickly with minimal exertion. Difficulty concentrating, other common symptoms include dizziness, visual disturbances such as seeing motion, blurred vision, inability to focus etc., headaches and/or migraine headaches, nausea, the feeling of pressure in the brain and confusion, fluctuations in temperature also affect suffers in particular heat. Many patients also describe ear symptoms such as hyperacusis, tinnitus, "fullness", pain, or even decreased hearing, and will also startle more easily. May have Photosensitivity and find it more difficult to walk in the dark as well as other sensitivities to chemicals and their smells. Cognitive impairment ("brain fog") includes an inability to recall words, short term memory loss, and an inability to multi-task, misspelling and mispronunciation of words, unable to use a computer for any length of time due to the visual over stimulation and some MdDS sufferers report they are even unable to watch television, the symptoms are extremely debilitating and fluctuate high and low on a daily basis. Excessive sleeping, MdDS sufferers can sleep up to 12 or more hours a day, depending on their symptom levels. Research reveals MdDS is not migraine related and many sufferers have never had migraine symptoms prior to the onset of the disorder.[1]
Mal De Debarquement greatly effects the working capacity of sufferers with many having to relinquish work, it also limits most other daily and social activities. Interestingly, the condition often abates to some degree when the patient is in motion such as in a car, train, plane, or boat, however once the motion ceases, the symptoms return often at much higher levels than when the journey first commenced. Symptoms can be increased by stress, lack of sleep, crowds, flickering lights, loud sounds, fast or sudden movements, enclosed areas or busy patterns.
MdDS is unexplained by structural brain or inner ear pathology and is thought to be perhaps a neurological syndrome most often caused by a motion trigger, but can occur spontaneously. Recent research has revealed that MdDs is vision and other sensors related. This differs from the very common condition of "land sickness" that most people feel for a short time after a motion event such as a boat cruise, aircraft ride, or even a treadmill routine.
Persistent MdDS
In MdDS, the symptoms persist for more than a month, possibly for many years, or indefinite, all medical treatment is palliative and sufferers with "Persistent MdDS" symptoms,[2] that last beyond 4 years with no remission will remain permanent and will be classified as totally and permanently disabled as MdDS remains incurable.
Epidemiology
The condition is thought to be under-reported in the medical literature. A study of 27 cases, conducted by Timothy C Hain in 1999, noted all but one patient to be female. The average age in this series was 49 years.[3] This apparent gender disparity, however, may be due in part to the fact that the questionnaire, which formed the basis of the study, was circulated in a publication with a predominantly female reader base.[3]
Subsequent studies have produced conflicting results with regard to the gender distribution of MdDS. The trends in Hain's report have recently been supported by the MdDS Balance Disorder Foundation,[4] in a study of over 100 individuals diagnosed with MdDS. The female:male ratio was approximately 9:1; the average age of onset was 43–45 years. However, another recent study found that 44% of subjects who had experienced MdDS for 2 years or more were male,[5] suggesting a more even distribution.
It has been shown to occur in excursions of as little as 30 minutes though it has been unclear how long it takes for symptoms to occur.[6] The most commonly reported inciting event was a prolonged ocean cruise (~45%), however shorter boating excursions (~22%), aircraft travel (~15%), and automobile travel (~8%) have all been described.
Mal de debarquement Syndrome has been noted as far back to the times of Erasmus Darwin in 1796,[7] and Irwin J A (1881) The pathology of seasickness.
MdDs sufferers will increase as people are travelling more than ever on cruise ships, airplanes and by car, more awareness of this disorder is needed.
Diagnosis
MdDS is diagnosed several ways, that being by the symptoms in particular the "constant rocking, swaying feeling" and the abatement of this feeling when in motion again and as a matter of exclusion.[6] There are no definitive tests that confirm MdDS, only tests that rule out other conditions, tests include hearing and balance, and MdDS is generally diagnosed by either a Neurologist or an Ear Nose & Throat Specialist.[6]
Research Studies
Repetitive Transcranial Magnetic Stimulation for Mal de Debarquement Syndrome
Despite MdDS causing significant disability, therapy for persistent MdDS remains virtually non existent, of more recent times a pilot study has commenced utilizing Repetitive Transcranial Magnetic Stimulation (rTMS) this being a method of neuromodulation in which a local magnetic field is applied over the scalp to induce an electric current in the cortical structures underlying the coil. Low-frequency rTMS (e1 Hz) induces local inhibition, whereas high frequency rTMS (Q5 Hz) induces local excitation. The TMS studies have proved to help in lowering the symptoms of MdDS if the treatment is ongoing, however it is not a cure for this debilitating disorder.
Vestibulo-Ocular Reflex Research 2014
At least one clinical trial on readaptation of the vestibulo-ocular reflex undertaken by Dr Mingja Dai has produced excellent results for a significant percentage of patients who have participated in the program.[8]
Dr. Mingjia Dai at Mount Sinai Hospital in New York City has developed a treatment that has successfully provided either a cure or substantial improvement in symptoms for 70% of the patients in the clinical trial phase.[8] The treatment involves a physical manipulation of the patient intended to readapt the vestibulo-ocular reflex. While the program is no longer in the research phase, Dr. Dai continues to accept patients for treatment.
Treatment
For most balance and gait disorders, some form of displacement exercise is thought helpful (for example walking, jogging, or bicycling but not on a treadmill or stationary bicycle). This has not been well-studied in MdDS however. Medications that suppress the nerves and brain circuits involved in balance (the benzodiazepine clonazepam for example) have been noted to help and can lower symptoms, but it is not a cure. It is not known whether medication that suppress symptoms prolong symptom-duration or not. Vestibular Therapy has not proved to be effective in treating MdDS.[9]
Additional research is being undertaken into the neurological nature of this syndrome through imaging studies. Treatment options need to be explored further for MdDS sufferers which remains incurable and permanent if the symptoms do not remit in a short period of time.
See also
- Motion sickness (Travel sickness)
- Seasickness
- Vertigo
- Space adaptation syndrome (Space flight "zero-g" and return)
References
- ^ Cha YH (2009). "Mal de debarquement". Semin Neurol. 29: 520–7. doi:10.1055/s-0029-1241038. PMC 2846419. PMID 19834863.
- ^ Cha, Yoon-Hee Cha (2009). "Mal de Debarquement". Seminars in Neurology. 29: 520–7. doi:10.1055/s-0029-1241038. PMC 2846419. PMID 19834863.
- ^ a b "Mal de debarquement", Archives of Otolaryngology - Head & Neck Surgery, 125 (6): 615–620, Jun 1999, doi:10.1001/archotol.125.6.615, PMID 10367916
{{citation}}: Unknown parameter|authors=ignored (help) - ^ "Understanding Mal de Débarquement Syndrome". MdDS Balance Disorder Foundation. Retrieved 2013-05-14.
- ^ "Clinical features and associated syndromes of mal de debarquement". Journal of Neurology. 255 (7): 1038–44. 2008. doi:10.1007/s00415-008-0837-3. PMC 2820362. PMID 18500497. NIHMS174090.
{{cite journal}}: Unknown parameter|authors=ignored (help) - ^ a b c "'Sea legs': sharpened Romberg test after three days on a live-aboard dive boat". Diving and Hyperbaric Medicine. 40 (4). South Pacific Underwater Medicine Society: 189–194. 2010. PMID 23111933.
{{cite journal}}: Unknown parameter|authors=ignored (help) - ^ Hain, Timothy C. "MdDs". dizziness-and-balance.com. Retrieved 22 July 2015.
- ^ a b Dai M, Cohen B, Smouha E, Cho C (2014). "Readaptation of the vestibulo-ocular reflex relieves the mal de debarquement syndrome". Front Neurol. 5: 124. doi:10.3389/fneur.2014.00124. PMC 4097942. PMID 25076935.
{{cite journal}}: CS1 maint: unflagged free DOI (link) - ^ http://www.dizziness-and-balance.com/disorders/central/mdd.html