Biomagnetic characterization of gastric dysrhythmias

胃节律失常的生物磁特征

• 批准号: 9257543
• 负责人: LEONARD A BRADSHAW
• 金额: $ 5.95万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9257543
• 关键词: Biomagnetic; characterization; gastric; dysrhythmias

DESCRIPTION (provided by applicant): Electrical activity in the stomach underlies functional physiology and pathophysiology. Our preliminary data show that the magnetic fields associated with the gastric slow wave contain critical parameters that help to characterize rhythms and may be important indicators of gastropathy. While both the electrogastrogram (EGG) and the magnetogastrogram (MGG) contain frequencies that correlate well with myoelectric potentials in the gastric musculature, additional spatiotemporal information in the MGG allows assessment of gastric propagation. We have shown that MGG propagation characteristics differ when comparing normal subjects with gastroparesis patients. We have also been able to compute the propagation gradient of the gastric syncytium from noninvasive MGG measurements and have shown its correlation with serosal electrode data. To continue our research on the magnetic fields of the stomach, we are proposing: (1) to use a realistic abdominal volume-conductor model to study how abdominal thickness affects EGG and MGG data and how normal and uncoupled gastric musculature affects EGG and MGG patterns. Data from our studies contradicted our original hypothesis that body mass index (BMI) significantly affects these signals, which was based on theoretical studies that predict such influences from abdominal layers. We will utilize the model developed under this aim in the analysis of our experimental data from the other specific aims. (2) We propose to determine how gastrectomy affects EGG and MGG. The normal intact stomach produces slow wave propagation patterns observable with MGG. We hypothesize that although non-gastric signals may appear near the gastric slow wave frequency range, these signals will not exhibit the same gastric propagation. (3) We will determine how gastric uncoupling changes MGG propagation patterns by inducing uncoupling surgically or pharmacologically to measure the changes in propagation and coupling assessed by EGG and MGG. (4) We will correlate the degree of gastroparesis with abnormal patterns of MGG propagation. We showed that a variety of abnormal propagation patterns characterize gastroparesis and we will determine whether these pattern differences differentiate the severity of the disease. (5) Finally, we will determine whether similar differences exist between diabetic and idiopathic gastroparetics, and we will determine how much variation exists between patients. The ability to consistently evaluate the electrical activity of the stomach in terms of both frequency dynamics and propagation characteristics will help us to better understand underlying pathologies that will in turn inform and direct better and more effective treatment options for gastroparesis patients, and ultimately for patients suffering a variety of gastric disorders.

描述（由申请人提供）：胃中的电活动是功能生理和病理生理学的基础。我们的初步数据表明，与胃慢波相关的磁场包含关键参数，有助于表征节奏，并且可能是胃病的重要指标。虽然静电图（EGG）和磁胃图（MGG）都包含与胃肌肉组织中肌电电位良好相关的频率，但MGG中的其他时空信息允许评估胃传播。我们已经表明，将正常受试者与胃轻瘫患者进行比较时，MGG传播特征有所不同。我们还能够通过非侵入性MGG测量来计算胃合胞体的传播梯度，并显示其与浆膜电极数据的相关性。为了继续对胃的磁场进行研究，我们提出：（1）使用逼真的腹部体积传导器模型研究腹部厚度如何影响卵和MGG数据以及正常和未偶联的胃肌肉如何影响卵和MGG模式。我们研究的数据与我们的原始假设相矛盾，即体重指数（BMI）显着影响这些信号，这是基于预测腹部层影响这种影响的理论研究。我们将利用此目的开发的模型来分析我们的其他特定目的的实验数据。 （2）我们建议确定胃切除术如何影响卵和MGG。正常完整的胃会产生可观察到MGG的慢波传播模式。我们假设，尽管非冬季信号可能会出现在胃慢波频率范围附近，但这些信号不会表现出相同的胃传播。 （3）我们将通过通过手术或药理诱导解偶联以测量鸡蛋和MGG评估的传播和耦合的变化来确定胃解偶联如何改变MGG传播模式。 （4）我们将将胃轻瘫的程度与MGG传播的异常模式相关联。我们表明，各种异常传播模式表征了胃轻瘫，我们将确定这些模式差异是否会区分疾病的严重程度。 （5）最后，我们将确定糖尿病和特发性胃气酸果中是否存在类似的差异，我们将确定患者之间存在多少变异。通过频率动力学和传播特征来始终如一地评估胃的电活动的能力将有助于我们更好地理解基本的病理，从而为胃轻瘫患者以及最终对患有多种胃部疾病的患者提供更好，更有效的治疗选择。