MdDS

Mal de debarquement syndrome (MdDS) is a less-known balance disorder that most commonly develops following an ocean cruise or other type of water travel and less commonly following air travel, train/car travel, or other physical/visual motion experiences. The symptoms typically reported primarily include: a sensation of rocking, swaying, and/or bobbing. Accompanied is a number of debilitating equilibrium, cognitive and psychological malfunction which result in  anxiety and lethargy. The symptoms may be last anywhere from a month to years. Our recent data show that there is a large portion of MdDS suffers developed motion/visual intolerance that not only aggravates their motion sensations but also could trigger a reversion after they were successfully treated.

Mechanism of MdDS (under construction):

Treatment of MdDS:  We have postulated that MdDS is a result of the maladaption of the vestibulo-ocular reflex (VOR)(2, 4). Based on this hypothesis, we developed a therapeutic protocol to readapt the VOR by visual/vestibular interaction (1). Patients are first tested for their rocking frequency, spontaneous nystagmus, circular drifting to determine the treatment parameters associated to their physical and descriptive symptoms.  Patients were then treated consecutively in 4- 5 days for about one hour on average per day.  In our first round of studies in 24 MdDS patients (1), about 75% of them were significantly getting better or cured. Since then we have studied more than 250 cases, the outcomes after the treatment are not altered.  There are some patients who have experienced a reversion, probably which was triggered visually or by passive motion or anxiety when and after traveling back home.  For this, we provide them with home treatments with video based methods and in the future with virtual reality approach. If they did correctly as guided, their symptoms will be reduced again. On the other hand, we are investigating the other in-lab approaches to desensitize their visual sensitivity and enhance their motion tolerance(3). The preliminary investigation shows that this protocol not only helps with their visual and motion tolerance but also with their balance. This could help with the reversion problem and will be included in the future treatment especially for those who has become motion intolerance.

References:

  1. Dai M., Cohen B., Smouha E., Cho C. Readaptation of the Vestibulo-Ocular Reflex Relieves the Mal de Debarquement Syndrome. 2014. v5, DOI: 10.3389, Frontiers in Neuro-otology, PMC4097942, PMID:  25076935: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4097942/
  2. Treatment of the Mal de Debarquement Syndrome: A 1-Year Follow-up. 2017, 05 May. Frontiers in Neuro-otology: https://doi.org/10.3389/fneur.2017.00175

  3. Dai, M., Raphan, T., Cohen, B. Adaptation of the Angular Vestibulo-Ocular Reflex (aVOR) to Head Movements in Rotating Frames of Reference. Exp Brain Res .2009 Jun;195(4):553-67 PMC Journal PMID: 1945841
  4. Dai, M., Raphan, T., Cohen, B. Prolonged reduction of motion sickness sensitivity. DOI: 10.1007, Exp Brain Res  2011 ;210(3-4):503-13 HIHMS: 309415 PMID: 21287155
  5. Guedry FE, Jr., Graybiel A (1962) Compensatory nystagmus conditioned during adaptation to living in a rotating room. J Appl Physiol 17: 398-404
  6.  Mal de Debarquement Syndrome: a survey on subtypes, misdiagnoses, onset and associated psychological features. https://link.springer.com/article/10.1007%2Fs00415-017-8725-3