Amniotic fluid volume: Rapid MR-based assessment at 28-32 weeks gestation

Abstract

• MR projection hydrography can be used to estimate amniotic fluid volume. • MR projection hydrography relies on the T2w signal from amniotic fluid. • Amniotic fluid volume (AFV) is more accurately assessed than with ultrasound.

Measuring intrauterine growth in healthy pregnancies using quantitative magnetic resonance imaging

“…We report a range of normative amniotic fluid volumes in the second and third trimesters of pregnancy, adding to the limited studies on this topic in fetal MRI 52 , 53 . In clinical practice, US is still the main modality used to assess amniotic fluid volume, but its accuracy is controversial 53 , 54 , 55 . A previous study had shown that MRI is a more accurate predictor of amniotic fluid volume compared to US 53 .…”

“…In clinical practice, US is still the main modality used to assess amniotic fluid volume, but its accuracy is controversial 53 , 54 , 55 . A previous study had shown that MRI is a more accurate predictor of amniotic fluid volume compared to US 53 . We did not observe a strong temporal evolution of amniotic fluid over GA, likely due to the highly dynamic nature of the production and resorption of amniotic fluid.…”

Lateral ventricular volume measurement by 3D MR hydrography in fetal ventriculomegaly and normal lateral ventricles

“…Although 3D ultrasound is more accessible and less expensive compared to MRI, it cannot possibly achieve the same. Ultrasound measurements can also be influenced by operator technique . Therefore, many studies have focused on the role of MRI for lateral ventricular volumetric measurement .…”

“…Ultrasound measurements can also be influenced by operator technique. 19 Therefore, many studies have focused on the role of MRI for lateral ventricular volumetric measurement. [8][9][10][12][13][14][15] Some researchers have measured lateral ventricular volumes by manual MSP, 8,12,13 whereas others have estimated those volumes from 3D reconstructed volumetric datasets.…”

“…16,17 MRH is characterized by the visualization of stationary or slowly flowing fluids in bright, high signal density structures, against dark backgrounds with very low signal intensities. 18 2D MRH, which utilizes heavily T 2 -weighted sequences, has been utilized to reveal fetal abnormalities and to measure amniotic fluid volumes, 18,19 although these did not measure fetal lateral ventricular volume directly. The reason for this is probably that projection hydrography makes lateral ventricular volumes difficult to assess because amniotic fluid and maternal bladder volumes are included.…”