Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.
Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand; Department of Surgery, Vanderbilt University, Nashville, TN, USA.
Comput Biol Med. 2023 Oct;165:107384. doi: 10.1016/j.compbiomed.2023.107384. Epub 2023 Aug 18.
Gastric motility is coordinated by bioelectric slow waves (SWs) and dysrhythmic SW activity has been linked with motility disorders. Magnetogastrography (MGG) is the non-invasive measurement of the biomagnetic fields generated by SWs. Dysrhythmia identification using MGG is currently challenging because source models are not well developed and the impact of anatomical variation is not well understood. A novel method for the quantitative spatial co-registration of serosal SW potentials, MGG, and geometric models of anatomical structures was developed and performed on two anesthetized pigs to verify feasibility. Electrode arrays were localized using electromagnetic transmitting coils. Coil localization error for the volume where the stomach is normally located under the sensor array was assessed in a benchtop experiment, and mean error was 4.2±2.3mm and 3.6±3.3° for a coil orientation parallel to the sensor array and 6.2±5.7mm and 4.5±7.0° for a perpendicular coil orientation. Stomach geometries were reconstructed by fitting a generic stomach to up to 19 localization coils, and SW activation maps were mapped onto the reconstructed geometries using the registered positions of 128 electrodes. Normal proximal-to-distal and ectopic SW propagation patterns were recorded from the serosa and compared against the simultaneous MGG measurements. Correlations between the center-of-gravity of normalized MGG and the mean position of SW activity on the serosa were 0.36 and 0.85 for the ectopic and normal propagation patterns along the proximal-distal stomach axis, respectively. This study presents the first feasible method for the spatial co-registration of MGG, serosal SW measurements, and subject-specific anatomy. This is a significant advancement because these data enable the development and validation of novel non-invasive gastric source characterization methods.
胃动力是由生物电慢波（SW）协调的，节律异常的 SW 活动与运动障碍有关。磁胃电图（MGG）是 SW 产生的生物磁测量的非侵入性方法。由于源模型尚未得到很好的发展，并且解剖变异的影响也未得到很好的理解，因此使用 MGG 进行节律异常识别目前具有挑战性。本文开发了一种新的方法，用于对浆膜 SW 电位、MGG 和解剖结构的几何模型进行定量空间配准，并在两只麻醉猪上进行了验证。电极阵列使用电磁发射线圈进行定位。在台式实验中评估了胃通常位于传感器阵列下方的体积中线圈的定位误差，对于与传感器阵列平行的线圈方向，平均误差为 4.2±2.3mm 和 3.6±3.3°，对于垂直线圈方向，平均误差为 6.2±5.7mm 和 4.5±7.0°。通过将通用胃拟合到多达 19 个定位线圈来重建胃几何形状，并使用 128 个电极的注册位置将激活图映射到重建的几何形状上。从浆膜记录到正常的近端到远端和异位 SW 传播模式，并与同时进行的 MGG 测量进行比较。正常近端到远端和异位 SW 传播模式下，归一化 MGG 的重心与浆膜上 SW 活动的平均位置之间的相关性分别为 0.36 和 0.85。本研究提出了一种可行的方法，用于 MGG、浆膜 SW 测量和特定于个体的解剖结构的空间配准。这是一项重大进展，因为这些数据可以为开发和验证新型非侵入性胃源特征化方法提供支持。
