MULTIMODALITY HEART PHANTOM MOTION VALIDATION STUDIES

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 目的 研究空间、时间分辨率和SNR要求，以优化、验证和估计： I.使用多模态真实心脏体模的心肌运动和欧拉应变（使用DENSE MRI） 二.使用DENSE MRI的来自体内小鼠心脏的心肌应变 方法 动物准备和监测：小鼠（雄性/雌性，CB 57 L、CD-1或FVB品系，体重H20 - 30 g）将在密封室中使用5%异氟烷诱导约3分钟。然后通过鼻锥对小鼠进行机械通气（使用1-2%异氟烷和100%氧气的混合物），并将小鼠以仰卧位放置在专门设计的摇篮中的鸟笼发射激励线圈或/和接收线圈的中间。将ECG导联连接至爪并连接至市售光纤记录系统（SA Instruments Inc.）用于监测电活动和心率。将使用直肠探头监测体温。空气管道循环加热空气，设定温度为37- 38 ℃，将动物保持在正常温度水平。所有研究将按照杜克大学和机构动物护理和使用委员会的研究伦理行为规则进行。 DENSE脉冲序列开发和优化：脉冲序列（PSD）的实施将通过在Excite EPIC环境（EPIC，通用电气，美国）中编程来实现，如单独的目标国际合作提案中所述。在所提出的工作中，将在多模态移动体模和小鼠中评估和验证脉冲序列性能，通过相位图重建、优化编码梯度和破碎机/扰流器强度-时间面积（编码强度[Genc]、持续时间[tenc]乘积）、重复（TR）、回波时间（TE）和混合时间（TM）以获得最佳T1弛豫加权。考虑到其超短收缩时间间期（总R-R间期的20-30%），将在小鼠中应用于体内小鼠成像并优化相同参数以获得最大SNR和CNR性能。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. AIM Investigation of the spatial, temporal resolution, and SNR requirements for the optimization, validation and estimation of: i. Myocardial Motion and Eulerian strain using a multimodality realistic heart phantom using DENSE MRI ii. Myocardial strain from the in vivo mouse heart using DENSE MRI METHODOLOGY Animal Preparation and Monitoring: Mice (male/female, CB57L, CD-1, or FVB strains, weightH20-30g) will be induced using 5% isoflurane in a sealed chamber for approximately 3 minutes. The mice will then be mechanically ventilated through a nose cone (with a mixture of 1-2% isoflurane and 100% oxygen to effect), and placed in the supine position in the middle of either a birdcage transmit excitation coil or/and a receive coil, in a specially designed cradle. ECG leads will be attached to the paws and connected to a commercially available fiber optic recording system (SA Instruments Inc.) for monitoring electrical activity and heart rate. A rectal probe will be used to monitor temperature. Air pipes with circulating heated air at a set temperature of 37-38oC will maintain the animals at normal temperature levels. All studies will be performed in accordance with the rules of ethical conduct of research at Duke University and the Institutional Animal Care and Use Committee. DENSE Pulse Sequence Development and Optimization: Implementation of the pulse sequence (PSD) will be achieved by programming in the Excite EPIC environment (EPIC, General Electric, USA), as described in a separate Targeted International Collaboration proposal. In the proposed work, the pulse sequence performance will be assessed and validated in the multi-modality moving phantom and in mice, though phase map reconstructions, optimization of encoding gradients and crusher/spoiler strength-time areas (encoding strength [Genc], time duration [tenc] product), repetition (TR), echo times (TE), and mixing times (TM) for optimal T1-relaxation weighting. Application in in-vivo mouse imaging and optimization of the same parameters for maximum SNR and CNR performance will be conducted in mice, considering its ultra short systolic time intervals (20-30% of the total R-R interval).