The laboratory has a strong interest in developing improved approaches to assessing muscle and nerve though engineering innovation. Much of this focus is in the realm of electrical impedance; however, other areas of interest include advancing standard electrophysiologic techniques, ultrasound enhancements, and fusing/combining multiple modalities. The images below provide some examples of work that we have been pursuing.
Finite element modeling studies demonstrating the impact of subcutaneous fat thickness on resistance and reactance impedance measures. These studies have helped to improve the design of our electrode arrays.
Initial 3-D computer-aided designs (CADs) of monopolar and concentric I-EMG needle electrodes based on standard EMG needles’ designs. I-EMG needle models were created in Comsol (Burlington, MA). The current and voltage EIM electrodes are shown in red and blue, respectively.
Example of finite element modeling being used to create a new tibialis anterior electrode array
Constant pressure transducer to ensure that regardless of pressure applied, a 10N force is maintained. The system is also built with accelerometers and gyroscopes to help measure movement and angle of the transducer relative to the limb.
Prototype EIT-US device developed in preparation for this proposal. a) sonulcent electrode array, coupling printed circuit board, and US probe, b) 3D printed housing to hold electrode array and coupling PCB in place,
c) Example multimodal image with conductivity display over gray-scale US. Note that the green dotted lines represent the skin-adipose interface (top line) and adipose-muscle interface (bottom line). This approach to segmentation will be useful for soft-prior image reconstruction.