1、 MRI , , MRI , , ; ; ; ; ; ; ; ; , E-mail: Research progresses in functional MRI of the placenta LI Yaodong ZHANG Linkui Department of Radiology, Qinghai Red Cross Hospital; Abstract Insufficiencies in placenta functions may result in a variety of severe prenatal and postnatal syndromes, which is re
2、sponsible for most pregnancy failures, and has long-term negative impacts on female adult health.Recent advances in f MRI studies of the placental in both animal models and humans, have significantly enriched our understanding concerning placental structure, blood flow, oxygenation status, metabolic
3、 profile, and pregnancy complications.The MRI methods including dynamic contrast enhanced MRI (DCE-MRI) , arterial spin labeling (ASL) , blood oxygen level dependent (BOLD) and oxygen enhanced (OE) , diffusion weighted MRI (DWI) , intravoxel incoherent motion (IVIM) , and magnetic resonance spectros
4、copy (MRS) , can be used to evaluate placental oxygenation, the tissue micro-structure, and properties of metabolism.In this review, we introduced the basis of these methods, summarized their progressesin both animal models and human studies, and discussed their limitations, challenges, and potentia
5、l application in future. Keyword Placenta; Dynamic contrast-enhanced; Arterial spin labeling; Blood oxygen level dependent; Oxygen enhanced; Diffusion weighted imaging; Intravoxel incoherent motion; Magnetic resonance spectroscopy; , , , , 1 , , , , , / (intrauterine growth restriction, IUGR) 1 MRI
6、, 30 , , , , MRI 2 3.0 T , MRI 3 MRI (f MRI) , IUGR 1 MRI (dynamic contrast enhanced MRI, DCE-MRI) DCE-MRI 4, , , 1.1 DCE-MRI MRI , , T1 T1WI , , , ( ) ( ) ( ) 4 , , , , ( ) ( ) , 5-6 1.2 DCE-MRI 5-6 , , , , 40%5 DCE-MRI , ( ) DCE-MRI , Gd-DTPA , , , 7 (SPIO) IUGR , 6 , SPIO , , IUGR 8 - , , 8 9-10
7、, DCE-MRI Frias 10 3D , , ( ) , DCE-MRI , CE-MRI 11-12, , 6,13, Brunelli 14 , , , IUGR 1.3 DCE-MRI , MRI DCE-MRI , ; , , 3,15, , , , ( ) DCE-MRI 3 , DCE-MRI , , , , ( SPIO) DCE-MRI 2 (arterial spin labeling, ASL) 2.1 ASL , , , , ASL (s) , ASL 16 , , 1 , 2 16 , , , 17: (1) , DCE-MRI ; (2) 2.2 Avni 18
8、 ASL , , , , , , , ASL , 18 ASL f MRI (flow-sensitive alternating inversion recovery, FAIR) -ASL , 19 Francis 20 FAIR-ASL IUGR , IUGR 21 , 2.3 1998 22-23 , ASL (SNR) 16,20 ASL f MRI SNR, 16 9.4 T MR , , 3 3 (BOLD) (oxygen enhanced, OE) 3.1 BOLD OE (Hb) T2WI-BOLD Hb , Hb BOLD (d Hb) , d Hb , T2 T2/T2
9、 (R2 R2) T2WI T2WI , ( ) / ( ) 24 OE-MRI T1 , T1 , T1 , p (O2) T1 24 3.2 BOLD-MRI , ( ) 25-26 , BOLD-MRI OE-MRI BOLD , BOLD BOLD 27, 4.7 T 28 17 d , , BOLD 25 29 , , , ( IUGR) 30 , BOLD , , BOLD Sorensen 29 , BOLD , , BOLD OE BOLD 29 Huen 31 OE-MRI , R1 , R1 , ; R2 , 2429 R2 149 ms, IUGR R2 88 ms, O
10、E-MRI BOLD-MRI 31 , MRI , 3.3 BOLD-MRI : (1) BOLD , (2) Hb (3) , BOLD (4) BOLD d Hb , Hb 32 BOLD-MRI OE-MRI - , , IUGR BOLD , BOLD , 32 4 (DWI) (intravoxel incoherent motion, IVIM) 4.1 DWI , , , , (b) DWI (ADC) ADC 2 b , ( b=0) b , ADC ADC , DWI ADC , , DWI IVIM-MRI DWI , , IVIM , b , 3 : (1) , ; (2) (f) , ; (3) , 33 4.2 Solomon 32 DWI (spatiotemporal encoding, SPEN) , b-BSAGdDTPA ADC , , , ADC , ADC 2 ; ADC , , , 32 IVIM-MRI IUGR , 33 DWI 32 ADC 34-35 33 ( IUGR ) ADC IVIM , ADC f Alison 33 IVIM IUGR , f 26%36%, ; f , ;IUGR ADC f ; f ; , IUGR , IUGR 32-33,36 , IVIM Sohlberg 37 , (34 ) 4.3
