Time-efficient accurate 3D myocardium scar quantification using RAPID imaging

描述（由申请人提供）：冠心病（CHD）仍然是美国第一大死亡原因。大多数冠心病患者临床症状严重，包括心肌梗死（MI），且心肌梗死的复发率在首发发作后显著增高。心肌梗死后心肌瘢痕的准确检测和定量对临床诊断至关重要，因为它与心功能密切相关，被证明是治疗预后的预测指标，并被广泛用作治疗评估的生物标志物。目前MI疤痕检测的金标准是使用基于磁共振（MR）的相敏反转恢复（PSIR）技术，该技术可以恢复反转脉冲后自旋磁化的极性。由于人们发现3D扫描比2D扫描提供更高的定量和检测精度，PSIR技术要完全适应临床可行的D技术，仍然面临两个主要挑战：1)低时间效率。因为PSIR技术需要额外的全采样参考扫描来恢复磁化方向，因此与非PSIR LGE扫描相比，扫描时间增加了一倍。因此，尽管3D PSIR可以潜在地提供更高的检测和量化精度，但它们只在研究环境中进行了探索。2)疤痕与鲜亮的血泊对比不明显。尽管PSIR重建确保了强烈的疤痕/组织对比，但通常明亮的血池信号仍然是量化疤痕的混淆因素，特别是对于心内膜下的细微疤痕。我们的长期目标是开发一种磁共振成像技术，作为常规临床实践中心肌疤痕检测/量化的一线诊断工具。新设计的RAPID重建，不需要第二次采集PS重建，将用于提高时间效率，它将与专用的血液抑制技术相结合，以改善疤痕/血液对比。新技术的准确性也将在临床环境中得到验证。通过成功实现这两个目标，我们期望开发和验证一种具有时间效率的临床定向3D活力成像技术，该技术可以显著提高当前心肌梗死检测/量化的准确性。

DESCRIPTION (provided by applicant): Coronary Heart Disease (CHD) remains the No.1 cause of death in the United States. The majority patients with CHD develop serious clinical symptoms, including myocardial infarction (MI), and the recurrence rate of MI becomes significantly increased after the initial attack. The accurate detection and quantification of myocardial scarring post-MI is critical for clinical diagnosis because it has been strongly associated with cardiac function, proven to be a predictive indicator for treatment prognosis, and is widely used as a biomarker for treatment evaluation. The current gold standard of MI scarring detection is to use magnetic resonance (MR) based Phase Sensitive Inversion Recovery (PSIR) technique, which can restore the polarity of the spin magnetization after inversion pulses. As 3D scans have been found to provide higher quantification and detection accuracy than 2D scans, the PSIR technique still faces two major challenges to fully adapt itself into a clinically viable D technique: 1) Low time-efficiency. Because the PSIR technique requires an extra fully sampled reference scan to restore the magnetization orientation, thus doubling scan time compared to non-PSIR LGE scans. As a result, although 3D PSIR can potentially provide improved detection and quantification accuracy, they have only been explored in research environments. 2) Poor contrast between the scar and bright blood pool. Although the PSIR reconstruction ensures strong scar/tissue contrast, the usually bright blood pool signal remains a confounding factor in quantifying scars, esp. for a subtle subendocardial scar. Our long-term goal is to develop an MR imaging technique as first-line diagnostic tool for myocardial scar detection/quantification in regular clinical practice. A newly designed RAPID reconstruction that does not require the 2nd acquisition for PS reconstruction will be used to improve the time efficiency and it will be combined with dedicated blood suppression techniques to improve the scar/blood contrast. The accuracy of the new techniques will also be validated in a clinical environment. By successfully achieving both aims, we expect to develop and validate a time-efficient clinically orientated 3D viability imaging technique that can significantly improve the current MI detection/quantification accuracy.