Novel MRI Assessment of Placental Structure and Function Throughout Pregnancy

妊娠期胎盘结构和功能的新型 MRI 评估

• 批准号: 10619529
• 负责人: ELFAR ADALSTEINSSON
• 金额: $ 69.82万
• 依托单位: BOSTON CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10619529
• 关键词: 3-Dimensional; Address; Anatomy; Blood; Blood Pressure; Blood Vessels; Chorionic villi; Clinical; Clinical Trials; Compensation; Complex; Computer Analysis; Data; Deceleration; Development; Diagnosis; Diagnostic; Diffusion; Disease; Echo-Planar Imaging; Electromagnetics; Evaluation; Excision; Fetal Development; Fetal Growth; Fetal safety; Fetus; Fingerprint; First Pregnancy Trimester; Future; Goals; Health; Heating; Histopathology; Human; Hyperoxia; Image; Impairment; Individual; International; Joints; Magnetic Resonance Imaging; Maps; Measures; Methodology; Methods; Modeling; Monitor; Morbidity - disease rate; Mothers; Motion; Nutrient; Organ; Outcome; Oxygen; Pathologist; Pattern; Perfusion; Periodicals; Physiology; Placenta; Placenta Diseases; Pre-Eclampsia; Pregnancy; Preparation; Productivity; Research Personnel; Safety; Scientist; Second Pregnancy Trimester; Spin Labels; Spiral Artery of the Endometrium; Structure; Structure of placental cotyledon; Structure of umbilical artery; Technology; Temperature; Third Pregnancy Trimester; Time; Tissues; Uterine Contraction; Villus; Work; body system; clinically relevant; diagnostic tool; experience; feasibility testing; fetal; fetal blood; image registration; in vivo; innovation; mortality; multimodality; new technology; novel; novel therapeutics; oxygen transport; pregnant; radio frequency; response; simulation; spatiotemporal; tool; treatment choice; treatment response; wasting

The placenta is a highly vascular organ, responsible for the interaction between mother and developing fetus. Close proximity of maternal blood, in intervillous spaces, and fetal blood, in chorionic villi, enables transport of nutrients, such as oxygen, from mother to fetus and removal of wastes. Perfusion of the intervillous spaces can be impaired by placental diseases, such as preeclampsia. Compromised placental perfusion impairs the exchange between maternal and fetal blood with potentially devastating impact on both mother and fetus. Today, no diagnostic tool can directly monitor regional placental perfusion, intervillous inflow, oxygen response and oxygen state. Clinicians still rely on indirect measures of placental health, such as fetal size and umbilical artery blood velocity. Induced delivery remains the treatment of choice for most placental disorders. New, effective technologies are desperately needed to monitor regional placental health in vivo. We assembled a team of technical MR experts, computational researchers, MR clinician scientists, experienced obstetricians and a internationally recognized placental biologist to address the need for clinically relevant technological advances in MRI for placental imaging. Here we will develop robust, quantitative measures of regional placental perfusion, intervillous inflow, oxygen response and oxygen state from late 2​nd trimester to term, with safety analysis and feasibility testing that pave the way for extension to late 1​st trimester. We will pilot and optimize our placental MRI measures in mothers with typical pregnancy (TP) and preeclampsia (PE) to determine if our novel MRI methods are tolerated by both groups and to evaluate their feasibility and potential as clinical tools to distinguish PE from TP placentas in individuals. Towards this end, we propose the following specific aims: ​1. Map placental perfusion and estimate intervillous inflow: We will develop a new model for diffusion imaging intravoxel incoherent motion (IVIM) for placental perfusion and develop a velocity selective spin labeling (VSSL) approach to estimate intervillous inflow. ​2. Map T1 and T2 to characterize changes in placental oxygen response and oxygen state​: We will develop 2D MR Fingerprinting (MRF) to create rapid joint T1 and T2 maps of placental oxygen response during hyperoxia and 3D MRF or multi-inversion echo planar imaging (MIEPI) to create volumetric joint T1 and T2 maps to determine the placental oxygen state. For Aims 1 and 2, we will correlate multimodal placental patterns in TP and PE with regional placental histopathology using our placental flattening method for guidance. ​3. Optimize imaging safety throughout pregnancy using temperature simulations​: We will focus on the major safety concern of radiofrequency (RF) tissue heating in the first-through-third trimester of pregnancy. We will build on our anatomically realistic numerical pregnant body models and expertise with electromagnetic simulations and develop accurate and pregnancy-specific thermal models to determine and experimentally validate safe and efficient RF exposure throughout pregnancy.

胎盘是一个高度血管的器官，负责母亲和发育中的胎儿之间的相互作用。 母体血液在绒毛间隙和胎儿血液在绒毛膜中的紧密接近，使得 从母亲到胎儿的营养物质，如氧气，以及废物的清除。绒毛间间隙的灌流可以 因胎盘疾病而受损，如先兆子痫。胎盘血流灌注受损 母亲和胎儿之间的血液交换，对母亲和胎儿都有潜在的破坏性影响。 今天，没有一种诊断工具可以直接监测区域胎盘血流、绒毛间流入、氧气反应 以及氧气状态。临床医生仍然依赖间接测量胎盘健康，如胎儿大小和脐带。 动脉血流速度。引产仍然是大多数胎盘疾病的首选治疗方法。新的, 迫切需要有效的技术来监测活体局部胎盘的健康状况。我们组装了一个 由技术MR专家、计算研究人员、MR临床科学家、经验丰富的产科医生组成的团队 和一位国际公认的胎盘生物学家，以解决临床相关技术的需求 磁共振胎盘成像的研究进展。在这里，我们将制定强有力的、量化的区域衡量标准 胎盘灌注、绒毛间流入、氧反应和氧状态从​晚期到足月， 安全性分析和可行性测试，为延长到​妊娠晚期铺平了道路。我们将试行和 优化我们对典型妊娠(TP)和先兆子痫(PE)母亲的胎盘MRI测量，以 确定我们的新MRI方法是否为两组所接受，并评估其可行性和潜力 作为临床上区分PE和TP胎盘的工具。为此，我们提出如下建议 具体目标：​1.绘制胎盘血流图和估计绒毛间血流：我们将开发一种新的模型 扩散成像体素内非相干运动(IVIM)在胎盘血流灌注中的应用 自旋标记(VSSL)方法估计绒毛间流入。​2.映射T1和T2以表征 胎盘氧反应和氧态​：我们将开发2D磁共振指纹技术来创建快速关节 高氧和3DMRF或多反转回波平面胎盘氧反应的T1和T2图 成像(MIEPI)创建体积关节T1和T2图，以确定胎盘的氧气状态。AIMS 1 2，我们将把TP和PE的多模式胎盘模式与局部胎盘组织病理学联系起来 使用我们的胎盘扁平化方法进行指导。​3.使用以下工具优化整个怀孕期间的成像安全性 温度模拟​：我们将关注射频(RF)组织加热的主要安全问题 妊娠的前三个月到第三个月。我们将在我们的解剖现实的数字怀孕的基础上 身体模型和电磁模拟的专业知识，并开发准确的和特定于怀孕的 确定和实验验证整个过程中安全有效的射频暴露的热模型 怀孕了。