Researchers at Icahn School of Medicine at Mount Sinai have developed a treatment for people who suffer from Mal de Debarquement Syndrome (MdDS), a rare but debilitating balance disorder. According to a study report, published online in the July 2014 issue of Frontiers in Neurology, MdDS is caused by a malfunctioning of the vestibule-ocular reflex (VOR), a mechanism in the inner ear that maintains balance and stabilizes the eyes during head movements. The new treatment developed by the research team at Mount Sinai works by re-adapting the VOR mechanism in patients with MdDS.

According to the study, people who suffer from MdDS can experience sensations of bobbing and swaying or sea sickness long after a sailing or boating excursion has ended. The symptoms of MdDS, which can reportedly last for months or years, include poor coordination, insomnia, headaches, anxiety, and depression. There has been no effective treatment for MdDS until now.

“Our study has provided the first effective treatment for this troublesome disorder, and we hope it provides relief to the thousands of people who may be affected worldwide,” said Bernard Cohen, MD, the Morris Bender Professor of Neurology at the Icahn School of Medicine at Mount Sinai.

A study subject with MdDS being treated in the Mount Sinai study.

A study subject with MdDS being treated in the Mount Sinai study.

The treatment developed by Dr Cohen, Mingjia Dai, PhD, and colleagues, re-adapts the VOR by moving the visual surroundings as the head is slowly rolled from side to side at the same frequency as the subject’s symptomatic rocking, swaying or bobbing.  In the study, the head roll caused vertical eye movements (nystagmus), and subjects tended to turn to one side when marching in place. Subjects were rocked or swayed at about one cycle per five seconds as they viewed a moving pattern of stripes.

The research team found that three to five treatments a day for one week were sufficient to produce a cure, and the movements and associated symptoms disappeared. Side effects of the treatments were reported as negligible. Of the 24 subjects that were treated in this study, 75% reported either a complete or substantial recovery during the one year post-treatment follow-up period. Although six subjects in the study reportedly had only transient improvement of symptoms, and one subject in the study did not respond to treatment, Dr Cohen feels the study results were promising.

“The work of our team also opens up a new area of research on how the Vestibulo-Ocular Reflex can produce head and body oscillations, and may eventually provide insight into other brain diseases that cause repetitive shaking and tremor of the head and body,” Dr Cohen said.

Mal de Debarquement Syndrome (MdDS) reportedly occurs in only a small fraction of those who experience Mal de Debarquement, and has been classified as a rare, disabling disease by the National Institutes of Health (NIH). Exact estimates of its prevalence are not available, but it is possible that there are hundreds of people with this syndrome in the United States and thousands worldwide, according to Dr Cohen.

Mingjia Dai, PhD, assistant professor of neurology, worked closely with Dr Cohen to develop the treatment, treated the subjects, and led the group at the Icahn School of Medicine at Mount Sinai. Co-collaborators in the study included Catherine Cho, MD, MSCR, assistant professor of neurology in the Eye Movement and Vertigo Program, and Eric Smouha, MD, associate professor of otolaryngology, and director of Otology-Neurotology. The study was supported by a grant from the National Institute on Deafness and Other Communication Disorders (NIDCD).

Source: Icahn School of Medicine at Mt. Sinai, and the National Institute on Deafness and Other Communication Disorders (NIDCD)

Photo Credits: © Andreas Karelias |; Mingjia Dai, PhD