Principal Investigator: James W. Tetrud, MD Project Staff: Eric E. Sabelman, PhD; Kevin McGill, PhD; and Ruth Yap, MS Project Category: Other This proposal was submited to NIH with The Parkinson's Institute, Sunnyvale, CA, as the lead institution and the VA Palo Alto Rehabilitation R&D Center as a consortium partner with PAIRE administration. Objective: A common disabling clinical feature of Parkinson's disease (PD) and other parkinson's syndromes (PS) such as progressive supranuclear palsy (PSP), multiple system atrophy (MSA) and vascular parkinsonism (VP) is freezing of gait (FOG), a cause of considerable disability including morbidity and mortality from falls. The long-term goal of this research is to reduce disability and risk of falls in these conditions by means of a Wearable Accelerometric Motion Analysis System (WAMAS). The WAMAS consists of 4 tri-axial accelerometers (2 mounted on the side of eye-glass frames and 2 on each hip) connected to a computer worn by the patient and capable of computing motion vectors. The computer can also generate a signal to administer a sensory stimulus from a device worn by the patient. In a pilot study, certain accelerometric variables associated with observed FOG episodes were used to develop a preliminary algorithm. In this study we will refine this algorithm to a specified sensitivity and selectivity and test a variety of sensory stimuli designed to "unlock" FOG. Research Plan: The ultimate goal of this research project is to reduce disability and injury caused by FOG episodes in patients with PS. To accomplish this goal, we will employ a wearable accelerometric motion analysis system to identify and shorten FOG episodes by means of a "real-time" feedback stimulus generated by the WAMAS computer. This approach is based on reports suggesting that gait disability and falls are proportional to the frequency and duration of FOG episodes. During the initial phase of this study, accelerometric parameters detected by the WAMAS system during FOG will be used to develop algorithms that sense the earliest phase of these episodes. The second phase of this study will be interventional, testing several sensory stimuli (visual, tactile, and auditory) reported to shorten the duration of FOG in patients with PD In a similar series of sessions we will also compare these interventional stimuli in PD patients during the "ON" phase (responding to PD medication) and "OFF" phase (not responding to PD medication). Our final goal is to apply these techniques to patients with other parkinsonian conditions (PSP, MSA and VP). Expected Outcome: This proposal addresses the question of recognition of dysfunctional motion, a capability essential for distinguishing PD from some other neurological conditions and also for tracking disease progress and effectiveness of therapies in individual patients. Identification of motor blocks, fluctuation, and freezing in real-time is necessary to our goal of developing a non-pharmacological intervention for facilitating smoother motion and reducing fall risk of PD patients. Funding Source: NIH Funding Status: Proposed |
