High-resolution mapping of in-vivo gastrointestinal slow wave activity using flexible printed circuit board electrodes: methodology and validation

Abstract

High-resolution, multi-electrode mapping is providing valuable new insights into the origin, propagation and abnormalities of gastrointestinal (GI) slow wave activity. Construction of high-resolution mapping arrays has previously been a costly and time-consuming endeavour, and existing arrays are not well suited for human research as they cannot be reliably and repeatedly sterilised. The design and fabrication of a new flexible printed circuit board (PCB) multi-electrode array that is suitable for GI mapping is presented, together with its in-vivo validation in a porcine model. A modified methodology for characterising slow waves and forming spatiotemporal activationmaps showing slow wavespropagation is also demonstrated. The validation study found that flexible PCB electrode arrays are able to reliably record gastric slow wave activity with signal quality near that achieved by traditional epoxy resin-embedded silver electrode arrays. Flexible PCB electrode arrays provide aclinicallyviable alternative to previously published devices for the high-resolution mapping of GI slow wave activity. PCBs maybe mass-produced at low cost, and are easily sterilised and potentially disposable, making them ideally suited to intra-operative human use.