Abstract
Objective
To investigate the clinical features and natural history of mal de debarquement (MdD).
Design
Retrospective case review with follow-up questionnaire and telephone interviews.
Setting
University Neurotology Clinic.
Patients
Patients seen between 1980 and 2006 who developed a persistent sensation of rocking or swaying for at least 3 days after exposure to passive motion.
Main outcome measure
Clinical features, diagnostic testing, and questionnaire responses.
Results
Of 64 patients (75 % women) identified with MdD, 34 completed follow-up questionnaires and interviews in 2006. Most patients had normal neurological exams, ENGs and brain MRIs. The average age of the first MdD episode was 39 ± 13 years. A total of 206 episodes were experienced by 64 patients. Of these, 104 episodes (51 %) lasted > 1 month; 18 %, > 1 year; 15 %, > 2 years; 12 %, > 4 years, and 11 %, > 5 years. Eighteen patients (28 %) subsequently developed spontaneous episodes of MdD-like symptoms after the initial MdD episode. There was a much higher rate of migraine in patients who went on to develop spontaneous episodes (73 %) than in those who did not (22 %). Subsequent episodes were longer than earlier ones in most patients who had multiple episodes. Re-exposure to passive motion temporarily decreased symptoms in most patients (66 %). Subjective intolerance to visual motion increased (10 % to 66 %) but self-motion sensitivity did not (37 % to 50 %) with onset of MdD.
Conclusion
The majority of MdD episodes lasting longer than 3 days resolve in less than one year but the probability of resolution declines each year. Many patients experience multiple MdD episodes. Some patients develop spontaneous episodes after the initial motion-triggered episode with migraine being a risk factor.