Placental functional assessment to predict adverse pregnancy outcome by MRI

Research Project

Project/Area Number	17K10401
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Radiation science
Research Institution	Kyoto University
Principal Investigator	Kido Aki 京都大学, 医学研究科, 助教 (80595710)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000) Fiscal Year 2019: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000) Fiscal Year 2018: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000) Fiscal Year 2017: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
Keywords	MRI / 胎盤 / IVIM / T2値
Outline of Final Research Achievements	The study aimed to evaluate the prognostic value of placental intravoxel incoherent motion (IVIM) parameters and T2-relaxation time, and their correlation with fetal growth and adverse outcomes, comparing umbilical artery (UmA) pulsatility index (PI). In 68 cases, UmA-PI and IVIM parameters (Dfast, Dslow, and f) were calculated. First, the associations of gestational age with placental IVIM parameters, T2-relaxation time, and placental thickness were evaluated. Secondly, all the parameters were compared between (1) those delivering small for gestational age and appropriate for gestational age neonates, (2) emergency caesarean section (ECS) and non-ECS, and (3) preterm birth and full term birth. In conclusion, T2 value (Z-score) and f showed significant associations with low birth weight and adverse outcomes of pregnancy. T2 value (Z-score) had better correlation with birth weight than UmA-PI. Therefore, placental IVIM and T2 Z-score are efficient biomarkers of placental dysfunction.
Academic Significance and Societal Importance of the Research Achievements	非侵襲的かつ客観的検査であるMRI検査において、非造影で得られる定量値が妊娠転帰と相関することが明らかとなり、出産前に胎児の状態を定量的に知ることができ、出産時に生じうる問題への対処が可能となると考えられる。