Safety and Efficacy of the BrainPort™ Balance Device to Improve Balance in Bilateral Vestibular Hypofunction

Inclusion Criteria: Documented history of acquired bilateral vestibular dysfunction for a duration of at least one year which has been unsuccessfully treated or reached a plateau with conventional vestibular rehabilitation. No greater than 2 successful attempts out of 6 on the NeuroCom Equitest Sensory Organization Tests 5 and 6. Failure on the Rotary Chair Vestibulo-ocular Reflex (VOR) Test as evidenced by a gain of less than or equal to -2 standard deviations at frequencies of .025, and .05 Hz. Normal corrected vision (20/40 or better). Able to read and understand the informed consent form, and willing to sign the informed consent form. Willing to complete all follow-up evaluations required by the study protocol. Able to stand for a period of 20 minutes in a stationary position with weight evenly distributed without moderate pain, muscle cramping or numbness in the lower extremities. Exclusion Criteria: Neurological disorders other than bilateral vestibular disorder, as determined by medical history and neurological screening procedure. Current oral health problems as determined by health questionnaire and an examination of the oral cavity. Cigarette smokers and those who use chewing tobacco. Currently taking either benzodiazepine or barbiturate medication. Any medical condition as determined by the health questionnaire that would interfere with performance on the postural stability evaluation tests. Known neuropathies of tongue or skin tactile system. Peripheral neuropathies of the lower extremities. Prior exposure to BrainPort™ balance device (does not apply to control group subjects who cross over). Subjects who are unwilling or unable to adhere to all study requirements, including completion of the training period, evaluation tests, and return to clinic for a follow-up visit. Subjects who have undergone middle ear or other surgery with sacrifice or damage to the chorda tympani, lingual, or hypoglossal nerve. Subjects who have an implanted device such as a pacemaker or defibrillator. If the subject is female, she is pregnant. If the subject is unwilling to discontinue medications for dizziness or imbalance 48 hours prior to beginning the study.