DESCRIPTION (provided by applicant): Our goal is to provide neurologists and other clinicians a method for the rapid, painless, non-invasive evaluation of children with neuromuscular disease. Pediatric neuromuscular disorders include muscular dystrophies, spinal muscular atrophy, and inflammatory myositis, and affect well over 100,000 children in the United States alone. Present-day clinical measures to assess disease status such as muscle strength testing or the Hammersmith rating scale are limited in a number of ways, including their having limited reproducibility, a lack of sensitivity to subtle disease change, their being strongly dependent on excellent subject cooperation, marked floor and ceiling effects (i.e., the tests are uninformative in very mild or very advanced disease), and their requiring considerable evaluator expertise and training. In order to care for children affected by neuromuscular disorders more effectively, a non-invasive and painless tool that can rapidly and accurately assess disease status with minimal subject cooperation is greatly needed. Such a tool could be used with individual patients, providing valuable data on the effectiveness of ongoing treatment or the potential need to alter therapy. Equally important, the tool could be used in clinical drug trials, helping to identify potential therapies more sensitively, more quickly and with fewer subjects than currently possible, thus greatly reducing study cost. Electrical impedance myography (EIM), we believe, is such a tool. In EIM, non-detectible, low- intensity, alternating electrical current is applied through two surface electrodes and resulting surface voltages are measured. Multiple published studies, both in adults and children, support that EIM is both highly reproducible and very sensitive to disease status. Moreover, given its entirely non-invasive, painless nature, it makes it an especially promising tool for use in children. Convergence Medical Devices, Inc. has as its primary focus and core competency the application of EIM for the assessment of muscle health. The specific aims of this Phase I SBIR, are to: (1) develop a hand-held EIM device for neuromuscular assessment in children, (2) test the device in a group of healthy adults to verify that it is safe and yields quality EIM data, and (3) study a group of 15 healthy children and 15 children with one relatively common pediatric disease, spinal muscular atrophy, to identify the system's tolerances and repeatability and preliminarily assess its sensitivity to health and disease status. The successful completion of these three aims will yield a preliminary prototype EIM device optimized for use in children. The insights we obtain using this device in both healthy and diseased children will offer a strong foundation for further device/software refinement necessary before launching a longitudinal study assessing clinical efficacy as part of a planned Phase II SBIR. PUBLIC HEALTH RELEVANCE: Over 100,000 children in the United States alone suffer from one or more serious neuromuscular diseases. However, current methods for diagnosing disease and assessing severity are insensitive and limited. The technique of electrical impedance myography has shown great promise as a technique for providing detailed data on muscle health without the limitations of current methods. Thus, the overall goal of this project is to develop a handheld, noninvasive electrical impedance device that can perform accurate, rapid assessments of muscle health in children.

PROJECT NARRATIVE Over 100,000 children in the United States alone suffer from one or more serious neuromuscular diseases. However, current methods for diagnosing disease and assessing severity are insensitive and limited. The technique of electrical impedance myography has shown great promise as a technique for providing detailed data on muscle health without the limitations of current methods. Thus, the overall goal of this project is to develop a handheld, noninvasive electrical impedance device that can perform accurate, rapid assessments of muscle health in children.