A multichannel vector biomagnetometer to characterize gastrointestinal slow waves

描述(由申请人提供)：我们建议对我们现有的超导量子干涉器件(SQUID)生物磁强计(特里斯坦637i型)进行升级，使我们能够(1)通过安装额外的通道来提高空间分辨率；以及(2)在记录阵列的中心增加额外的磁矢量传感器。升级后的仪器将具有更强的能力，以更高的空间分辨率检测潜在的生物电活动，区分生物电活动的多种来源，并识别生物电活动的细微时空变化。胃肠道电活动的生物磁学检测提供了非侵入性诊断和疾病状态表征的可能性。升级后的设备的主要应用将是检测胃和肠道慢波。在项目1中的胃研究中，目前的仪器提供了平均传播速度的确定，而胃传播速度表现出已知的空间梯度。改进后的仪器空间分辨率的提高将使我们能够计算不同胃区的传播速度。检测肠慢波需要更高的空间分辨率，这是因为(1)与胃慢波相比，源的相对大小以及(2)在感兴趣的肠段附近存在多个相邻的小肠段。空间分辨率的提高以及新的矢量传感器将使我们能够更好地区分这些多个来源，这对项目2的成功至关重要。此外，空间分辨率的提高将提高我们在项目3中的建模能力。最后，我们将使用升级后的设备来研究胎儿心磁图。

DESCRIPTION (provided by applicant): We propose an upgrade to our existing Superconducting QUantum Interference Device (SQUID) biomagnetometer (Tristan Model 637i) that will allow us (1) to increase the spatial resolution by installing additional channels; and (2) to add additional magnetic vector sensors in the center of the recording array. The upgraded instrument will have a greater ability to detect underlying bioelectrical activity with higher spatial resolution, to discriminate multiple sources of bioelectric activity and to identify subtle spatiotemporal variations in bioelectrical activity. The biomagnetic detection of gastrointestinal electrical activity offers the possibility of noninvasive diagnosis and characterization of disease states. The primary application of the upgraded device will be the detection of gastric and intestinal slow waves. In gastric studies in Project 1, the current instrumentation provides for the determination of an average propagation velocity, whereas the gastric propagation velocity exhibits a known spatial gradient. The increased spatial resolution of the modified instrument will allow us to compute the propagation velocity in different gastric regions. The detection of intestinal slow waves requires higher spatial resolution owing to (1) the relative size of the source compared with the gastric slow wave and (2) the presence of multiple adjacent small bowel segments in the vicinity of the segment of interest. The increased spatial resolution along with the new vector sensors will better enable us to distinguish these multiple sources, critical to the success of Project 2. Additionally, increased spatial resolution will improve our modeling abilities in Project 3. Finally, we will use the upgraded device to study the fetal magnetocardiogram.