NMR IMAGING AND RELAXATION PARAMETER MAPPING OF THE HUMAN PLACENTA POST PARTUM

产后人胎盘的 NMR 成像和松弛参数映射

• 批准号: 7358778
• 负责人: Chardonnay Julia Vance
• 金额: $ 0.31万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-06-01 至 2007-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7358778
• 关键词: NMR; IMAGING; RELAXATION; PARAMETER; MAPPING

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. Introduction: In the United States, Pre-Eclampsia (PE) occurs in roughly 10% of pregnancies, and is responsible for at least 20% of maternal deaths and 15% of premature births in the U.S. every year, worldwide these numbers are much higher. Several lines of evidence point towards poor placental implantation and subsequent malformation and dysfunction as a root cause of this disease. Since MR imaging is a sensitive modality with which we can study the in vivo placenta with minimal risk to the fetus, and since very little is known about the magnetic properties of the human placenta at 1.5 Tesla, this study of the relaxation parameters of the post partum human placenta was undertaken on 7 different singleton pregnancies. Placentas were collected from: 2 healthy pregnancies, 3 w/ mild PE, and 2 exhibiting severe PE. Methods and Discussion: Placentas were collected, secured in a container of 0.5% NaCl water, and MR scans performed at room temperature in a 1.5T GE Signa scanner within 24 hours of birth. Basic information about the severity of PE was recorded. A single channel body coil used for transmit was paired with an 8 channel head coil for signal reception. All image sets consisted of five 10mm slices ( 5mm spacing) through the placenta, NEX=1 and 256x256 data points. The T1 image sets consisted of 4 TRs all with a minimum full TE (14 ms). The T2 image sets consisted of 4 TEs with a TR of 2 sec. Relaxation times were calculated from the least squares fit to the equations. Slice by slice, regions of varying sizes but completely within the placenta were chosen by hand, and average relaxation times were computed as the mean of relaxation times pixel by pixel within each region, along with the average S.D. of these times within each region.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。简介：在美国，子痫前期（PE）发生在大约10%的妊娠中，并且每年在美国造成至少20%的孕产妇死亡和15%的早产，全球这些数字要高得多。几条证据表明，胎盘植入不良和随后的畸形和功能障碍是这种疾病的根本原因。由于磁共振成像是一种敏感的方式，我们可以研究体内胎盘，对胎儿的风险最小，因为很少有人知道在1.5特斯拉的人类胎盘的磁特性，产后人类胎盘的弛豫参数的研究进行了7个不同的单胎妊娠。胎盘采集自：2例健康妊娠、3例轻度PE和2例重度PE。方法和讨论：收集胎盘，固定在0.5%NaCl水的容器中，并在出生后24小时内在室温下在1.5T GE Signa扫描仪中进行MR扫描。记录PE严重程度的基本信息。用于传输的单通道体线圈与用于信号接收的8通道头部线圈配对。所有图像集均由5个穿过胎盘的10 mm切片（间距5 mm）组成，NEX=1和256 x 256数据点。T1图像集由4个TR组成，均具有最小完整TE（14 ms）。T2图像集由4个TE组成，TR为2秒。弛豫时间由方程的最小二乘拟合计算。逐层切片，手动选择大小不同但完全在胎盘内的区域，并计算平均弛豫时间，作为每个区域内逐像素弛豫时间的平均值，沿着平均S.D.在每个地区的这些时间。