Innovative Electrode Designs for Next Generation Electrical Impedance Myography

Project SummaryElectrical impedance myographyEIMis a non invasive technique for muscle evaluation that is finding increased application in a variety of neuromuscular diseases ranging from amyotrophic lateral sclerosis to muscular dystrophy to radiculopathyIn EIMa weak electrical current is passed between two electrodes through a muscle of interesttwo additional electrodes measure the resulting voltage patternsDiseases impact the normal conductive and resistive properties of tissueproviding diagnostic informationas well as data on disease statusincluding progression or the effects of therapyThe development and application of EIM technology is the main focus of MyolexIncThe company has developed a convenientcompact EIM systemthe mViewthat has been used in a number of academicSBIR fundedand pharma supported clinical studies in both children and adultsHoweverthe electrode sensor has not been optimized to ensure high quality data collectionThere are two specific limitationsFirstthe existing electrode topologyi ethe specific electrode sizeshapeand inter electrode distanceshas been based mainly on intuition rather than on dedicated analysesSecondthe sensor is largenot cost effectiveand subject to high contact impedances due to limitations in the electrode materialin order to achieve good skin contactit is necessary to repeatedly apply saline directly to the skin or probewhich leads to inconsistencies in the dataIn this PhaseSBIR applicationwe propose to refine these structural and technical aspects of sensor designIn Specific Aimwe will utilize finite element modelsFEMsto assist in evaluating a variety of potential innovative sensor designs to identify those that most effectively interrogate a variety of muscles in adults and childrenThis modeling will study the effect of improved electrode spacing and variations in electrode size and shapeIn Specific Aimwe will prototype a basic electrode array incorporating a hydrophilic foam material that we have already identified as providing high quality impedance data without artifactThis new array will use the improved electrode topologies of AimIn Specific Aimwe will pilot these new arrays inhealthy adult subjectssubjects with primary neurogenic diseaseandsubjects with primary myopathic diseaseevaluating specific quantifiable metricsincluding repeatabilitysensitivity to muscle conditioncomfortskin contact artifactsand diagnostic capabilityAt the conclusion of this workwe will be in a position to make a go no go decision as to the success of this effort and whether to pursue a Phaseapplication focused on making additional improvements to the mView system itselfincluding modifications to the impedance measuring unitAfter this developmental effort is completedwe will test this refined system and sensors in a larger cohort of healthy and diseased individuals of all agesincluding childrenWe will ultimately plan to seek FDA approval for this improved EIM system Project NarrativeElectrical impedance myographyEIMis a non invasive technology for the assessment of neuromuscular disease that is the primary focus of MyolexIncWhile currently effectivethe technology has not been fully optimized to ensure high sensitivityaccuracyease of useand cost effectivenessIn this proposed projectthe electrode sensor will be improved to make it both more sensitive to muscle condition and more convenient and effective to use in adults and children of all ages