Developing Robust Treatment Options for Mal de Débarquement Syndrome

Icahn School of Medicine at Mount Sinai

Summary

Mal de Débarquement Syndrome (MdDS) is an under-recognized balance disorder, which is manifested by persistent false sensations of oscillatory self-motion (rocking/swaying) and/or pulling in a specific direction (gravitational pull). Patients with MdDS typically experience additional presumably secondary symptoms, such as heightened sensitivity to visual motion (visually induced dizziness, VID), physical motion (motion sickness, MS), and other debilitating physical, cognitive, or affective problems. MdDS was previously considered intractable, and only recently was a breakthrough made in the clinical laboratory with an introduction of a visual-vestibular therapy protocol, yielding a significant long-term improvement of symptoms, including complete remission, in about 50% of patients. However, the approach is limited in several ways. Firstly, there is a practical limitation in implementing the treatment protocol, which requires a specialized set-up for visual stimulation in a dedicated room. This research will address this limitation by testing the utility of virtual reality technology to implement the treatment protocol. Secondly, patients often retain residual symptoms of VID and MS susceptibility, which often act as a trigger for the recurrence of MdDS. This limitation will be addressed by supplementing the original approach with an additional treatment focusing on VID or MS susceptibility. Thirdly, although the original protocol focused on reducing rocking/swaying sensations, gravitational pull often co-occurs with such sensations, and some experience only that motion sensation. This limitation will be addressed by modifying the original protocol. Two hundred patients with MdDS will be recruited for the study. Bias will be controlled by randomized group assignment and the use of placebo treatments. Patients will be treated for 1-2 hours a day for 5 days. Patients will be followed for up to 6 months. The proposed study will facilitate improved outcomes for MdDS by broadening its treatment options.

Description

Objectives This study aims to improve outcomes of MdDS by broadening its treatment options. Specifically, to improve access to the VOR readaptation treatment, the investigators will test the efficacy of VR goggles in generating visual motion to treat MdDS. If proven to be effective, MdDS patients can be treated locally in many vestibular therapy offices, not only for initial treatment but also for remedial or follow-up treatment when symptoms return. To improve long-term outcomes of MdDS, the investigators will evaluate the efficacy of the treatment of a complementary approach combined with VO…

Interventions

Behavioral

VOR Readaptation

The stimulus will be a combination of horizontal visual motion and a head maneuver. The subject will sit in a stationary chair, and a treatment provider will stand behind the subject. While the subject views the slow horizontal motion up to 10°/s of vertical stripes, the provider will gently hold the head of the subject above the ears and tilt the head in the roll (side-to-side) or pitch (up-down) plane by approximately ±20° at the frequency of 0.2 to 0.05 Hz for up to 10 min. The treatment will be repeated with breaks of approximately 5 min. A treatment session will last no longer 120 min including the breaks. In Groups 1, 3, and 4, subjects will sit in a chair placed in the center of a cylindrical enclosure of a 95 cm radius, and full-field visual motion will be generated with light projected on the wall of this chamber. In Group 2, visual motion will be presented on the screen of a VR headset. Unlike groups 3 and 4, groups 1 and 2 do not receive any complementary treatment.

Behavioral

VOR Habituation

The subject will sit in a chair placed in the center of a cylindrical enclosure of a 95 cm radius. Physical motion will be generated by rotating the chair sinusoidally to the left and right, and full-field visual motion will be generated with light projected on the wall of this chamber. Velocity storage will be weakened by inducing a conflict between physical and visual motions. Subjects will be first treated with a stimulus with a peak speed of 5°/s. The stimulus speed will be gradually increased from 5°/s on Day 1 to 40°/s on Day 5. In total, the subjects are expected to undergo 200-280 min of treatment over the five days, broken up into several 10-20 min sessions per day with a 10-min break in between. If signs or symptoms of motion sickness are reported by the subject (nausea, sweating), the session will be immediately paused. Treatment may be continued after a short rest if the discomfort is alleviated or on the following day.

Behavioral

Visual Motion Desensitization

The subject will be situated in darkness and view the movement of a visual pattern presented on a disk, sized 1 m in diameter and placed 1 m away from the subject with its center at the eye level. The disk will be rotated clockwise and counter-clockwise for up to 10 min at a fixed maximal speed within a treatment session but varying across sessions between 5 to 60°/s. Within a single session, the visual stimulus will be first presented with the subject sitting upright in a chair, and then the treatment will be repeated with the subject standing. The disk will be mounted on a vertical sled, so the center of rotation can be kept at the eye level when sitting and standing. A treatment session will be repeated or conducted with an increased visual motion speed up to 60°/s according to the subject's readiness. In total, the subjects are expected to undergo up to 300 min of treatment over the five days, broken up into several sessions per day with a 10-min break in between

Behavioral

Opposing visual motion stimulus

The investigators characterize gravitational pull as a misaligned sense of upright in the velocity storage mechanism, and hypothesize that that this misalignment can be corrected with an opposing visual motion stimulus, e.g., backward pulling will be corrected with upward visual motion. Patients in Group 5 will undergo view visual motion in a physical setting, and those in Group 6 under a VR setting. In total, the subjects are expected to undergo up to 300 min of treatment over the five days, broken up into several sessions of 1-10 min per day with an approximately 5-min break in between.

Developing Robust Treatment Options for Mal de Débarquement Syndrome

Summary

Description

Eligibility

Interventions

Location