title: Three-Dimensional Innervation Zone Imaging from Multi-Channel Surface EMG Recordings.
abstract: There is an unmet need to accurately identify the locations of innervation zones (IZs) of spastic muscles, so as to guide botulinum toxin (BTX) injections for the best clinical outcome. A novel 3D IZ imaging (3DIZI) approach was developed by combining the bioelectrical source imaging and surface electromyogram (EMG) decomposition methods to image the 3D distribution of IZs in the target muscles. Surface IZ locations of motor units (MUs), identified from the bipolar map of their MU action potentials (MUAPs) were employed as a prior knowledge in the 3DIZI approach to improve its imaging accuracy. The performance of the 3DIZI approach was first optimized and evaluated via a series of designed computer simulations, and then validated with the intramuscular EMG data, together with simultaneously recorded 128-channel surface EMG data from the biceps of two subjects. Both simulation and experimental validation results demonstrate the high performance of the 3DIZI approach in accurately reconstructing the distributions of IZs and the dynamic propagation of internal muscle activities in the biceps from high-density surface EMG recordings.
authors.affiliation: Department of Biomedical Engineering, University of Houston, 3605 Cullen Blvd, Houston, TX77004, USA.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Biomedical Engineering, University of Houston, 3605 Cullen Blvd, Houston, TX77004, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Ning
authors.affiliation: Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston, 7000 Fannin St., Houston, TX, USA.|TIRR Memorial Hermann Research Center, 1300 Moursund St., Houston, TX, USA.
authors.forename: Sheng
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston, 7000 Fannin St., Houston, TX, USA.|TIRR Memorial Hermann Research Center, 1300 Moursund St., Houston, TX, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Zhou
authors.affiliation: Sensory Motor Performance Program, Rehabilitation Institute of Chicago, 345 East Superior St., Chicago, IL, USA.|Department of Physical Medicine and Rehabilitation, Northwestern University, 710 North Lake Shore Drive, Chicago, IL, USA.
authors.forename: William Z
authors.initials: WZ
authors.lastname: Rymer
authors.affiliation: Department of Biomedical Engineering, University of Houston, 3605 Cullen Blvd, Houston, TX77004, USA.
authors.forename: Yingchun
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000200:Action Potentials / Q000502:physiology; D001132:Arm / Q000502:physiology; D003198:Computer Simulation; D004576:Electromyography / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D018482:Muscle, Skeletal / Q000294:innervation* / Q000502:physiology
keywords: Electromyography (EMG); bioelectrical source imaging; innervation zone (IZ); motor unit (MU); motor unit action potential (MUAP); surface EMG decomposition