Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama.
Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
Neurogastroenterol Motil. 2019 Jan;31(1):e13449. doi: 10.1111/nmo.13449. Epub 2018 Aug 20.
Improved understanding of the details of gastric slow wave propagation could potentially inform new diagnosis and treatment options for stomach motility disorders. Optical mapping has been used extensively in cardiac electrophysiology. Although optical mapping has a number of advantages relative to electrical mapping, optical signals are highly sensitive to motion artifact. We recently introduced a novel cardiac optical mapping method that corrects motion artifact and enables optical mapping to be performed in beating hearts. Here, we reengineer the method as an experimental tool to map gastric slow waves.
The method was developed and tested in 12 domestic farm pigs. Stomachs were exposed by laparotomy and stained with the voltage-sensitive fluorescence dye di-4-ANEPPS through a catheter placed in the gastroepiploic artery. Fiducial markers for motion tracking were attached to the serosa. The dye was excited by 450 or 505 nm light on alternate frames of an imaging camera running at 300 Hz. Emitted fluorescence was imaged between 607 and 695 nm. The optical slow wave signal was reconstructed using a combination of motion tracking and excitation ratiometry to suppress motion artifact. Optical slow wave signals were compared with simultaneously recorded bipolar electrograms and suction electrode signals, which approximate membrane potential.
The morphology of optical slow waves was consistent with previously published microelectrode recordings and simultaneously recorded suction electrode signals. The timing of the optical slow wave signals was consistent with the bipolar electrograms.
Optical mapping of slow wave propagation in the stomach is feasible.
对胃慢波传播细节的深入了解，可能为胃动力障碍的新诊断和治疗方案提供信息。光学标测在心脏电生理学中得到了广泛应用。尽管光学标测相对于电标测具有许多优势，但光学信号对运动伪影非常敏感。我们最近引入了一种新的心脏光学标测方法，可以校正运动伪影，使光学标测能够在跳动的心脏上进行。在这里，我们将该方法重新设计为一种实验工具，用于标测胃慢波。
该方法在 12 头国产农场猪中进行了开发和测试。通过放置在胃网膜动脉中的导管对胃进行剖腹术暴露，并通过导管注入电压敏感荧光染料二-4-ANEPPS 进行染色。用于运动跟踪的基准标记物附着在浆膜上。荧光染料通过在运行频率为 300Hz 的成像相机的交替帧上用 450nm 或 505nm 光激发。发射荧光在 607nm 至 695nm 之间成像。通过运动跟踪和激发比色法的组合重建光学慢波信号，以抑制运动伪影。光学慢波信号与同时记录的双极电图和近似膜电位的抽吸电极信号进行了比较。
光学慢波的形态与先前发表的微电极记录和同时记录的抽吸电极信号一致。光学慢波信号的时间与双极电图一致。
胃慢波传播的光学标测是可行的。
