Dual Energy Computed Tomography for Determining Coronary Lesion-Specific Ischemia

双能量计算机断层扫描用于确定冠状动脉病变特异性缺血

• 批准号: 8611962
• 负责人: Peter Edic
• 金额: $ 83.38万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-04 至 2018-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8611962
• 关键词: Dual; Energy; Computed; Tomography; Determining

DESCRIPTION (provided by applicant): The OVERALL OBJECTIVE of this application is to develop a novel quantitative computed tomography (CT)-based method for precise identification of coronary artery lesions that cause ischemia. At present, no non-invasive test exists that determines both coronary artery disease (CAD) stenosis severity and whether a stenosis causes ischemia, or reduced myocardial perfusion. Physiologic stress testing by myocardial perfusion imaging (MPI) is the traditional method for evaluating CAD, and identifies ischemia but not stenoses. In contrast, coronary CT angiography (CCTA) enables direct anatomic visualization of CAD, but cannot discriminate whether a stenosis causes ischemia. By invasive methods, a combined anatomic-physiologic approach to CAD evaluation by invasive coronary angiography and fractional flow reserve (FFR), respectively, improves diagnosis of patients with stenoses that cause ischemia, reduces unnecessary revascularization, and improves clinical outcomes. Recently, a combined anatomic-physiologic approach by non-invasive methods has become possible by the addition of CT perfusion (CTP) to CCTA. Similar to MPI, CTP permits physiologic assessment of stenoses through measures of regional myocardial signal attenuation. Early studies of CTP have been constrained by several limitations, including: 1) shading artifacts; 2) motion artifacts; 3) lack of a quantitative method for assessing perfusion; 4 excess radiation; and 5) an inability to pinpoint specific lesions that cause ischemia. Projection based dual-energy CT (DECT) is a novel CT technology that directly addresses many of these limitations, providing the potential for dramatic reduction in artifacts and quantitative measurement of myocardial perfusion. Coupled with improvements in temporal resolution that reduce motion artifacts, DECT holds the potential to improve the diagnostic accuracy of CTP, with an undoubtedly positive and significant impact on the current diagnostic approach to patients with suspected CAD. The OVERALL HYPOTHESIS of this proposal is that a novel quantitative projection-based DECT-based method will enable discrimination of individuals who suffer from myocardial ischemia as well as the identification of the specific coronary artery lesions that are the cause. For this study, there are 3 specific aims: 1) Develop a novel DECT method that accurately quantifies material density; 2) Determine the in vitro diagnostic accuracy of novel DECT method to characterize myocardial perfusion; 3) Evaluate the in vivo diagnostic accuracy of CTP by the novel DECT method to determine coronary lesion-specific ischemia, as compared to an invasive FFR "gold" standard.

描述（由申请人提供）：本申请的总体目标是开发一种基于定量计算机断层扫描（CT）的新型方法，用于精确识别导致缺血的冠状动脉病变。目前，尚无非侵入性测试可以确定冠状动脉疾病 (CAD) 狭窄的严重程度以及狭窄是否导致缺血或心肌灌注减少。通过心肌灌注成像 (MPI) 进行生理应激测试是评估 CAD 的传统方法，可以识别缺血但不能识别狭窄。相比之下，冠状动脉 CT 血管造影 (CCTA) 可以直接显示 CAD 的解剖结构，但无法区分狭窄是否导致缺血。 通过侵入性方法，分别通过侵入性冠状动脉造影和血流储备分数 (FFR) 进行 CAD 评估的解剖生理学相结合的方法，可以改善对导致缺血的狭窄患者的诊断，减少不必要的血运重建，并改善临床结果。最近，通过在 CCTA 的基础上添加 CT 灌注 (CTP)，采用非侵入性方法的解剖生理学联合方法已成为可能。与 MPI 类似，CTP 允许通过测量局部心肌信号衰减来对狭窄进行生理评估。 CTP 的早期研究受到一些限制，包括：1）阴影伪影； 2）运动伪影； 3）缺乏评估灌注的定量方法； 4 辐射超标； 5) 无法查明导致缺血的特定病变。 投影 基于双能 CT (DECT) 是一种新颖的 CT 技术，可直接解决许多这些限制，提供显着减少伪影和定量测量心肌灌注的潜力。再加上时间分辨率的提高可减少运动伪影，DECT 有望提高 CTP 的诊断准确性，这无疑对当前疑似 CAD 患者的诊断方法产生积极而重大的影响。该提案的总体假设是，一种基于 DECT 的新型定量预测方法将能够区分患有心肌缺血的个体，并识别导致心肌缺血的特定冠状动脉病变。本研究有 3 个具体目标：1）开发一种新型 DECT 方法，准确量化材料密度； 2）确定新型DECT方法表征心肌灌注的体外诊断准确性； 3) 与侵入性 FFR“金”标准相比，通过新型 DECT 方法评估 CTP 的体内诊断准确性，以确定冠状动脉病变特异性缺血。