Characterization of Uterine Motion in Early Gestation Using MRI-Based Motion Tracking

Thomas Martin,Rinat Masamed,Xinzhou Li,Holden H Wu,Sherin U Devaskar,Kyunghyun Sung,Teresa Chanlaw,Tess Armstrong,Sarah Choi,Carla Janzen,Irish Del Rosario

doi:10.3390/diagnostics10100840

Thomas Martin, Rinat Masamed + Show 9 more

Open Access

https://doi.org/10.3390/diagnostics10100840

Copy DOI

Journal: Diagnostics	Publication Date: Oct 19, 2020
Citations: 6	License type: CC BY 4.0

Affiliation: University of California, Los Angeles, UCLA Health

Abstract

Magnetic resonance imaging (MRI) is a promising non-invasive imaging technique that can be safely used to study placental development and function. However, studies of the human placenta performed by MRI are limited by uterine motion and motion in the uterus during MRI remains one of the major limiting factors. Here, we aimed to investigate the characterization of uterine activity during MRI in the second trimester of pregnancy using MRI-based motion tracking. In total, 46 pregnant women were scanned twice (first scan between 14 and 18 weeks and second scan between 19 and 24 weeks), and 20 pregnant subjects underwent a single MRI between 14 and 18 weeks GA, resulting in 112 MRI scans. An MRI-based algorithm was used to track uterine motion in the superior-inferior and left-right directions. Uterine contraction and maternal motion cases were separated by the experts, and unpaired Wilcoxon tests were performed within the groups of gestational age (GA), fetal sex, and placental location in terms of the overall intensity measures of the uterine activity. In total, 22.3% of cases had uterine contraction during MRI, which increased from 18.6% at 14–18 weeks to 26.4% at 19–24 weeks GA. The dominant direction of the uterine contraction and maternal motion was the superior to the inferior direction during early gestation.

Highlights

Placental function and growth are critically important to fetal health and development [1,2,3].Ultrasound is the primary technique for imaging the fetus and placenta primarily due to its proven utility, easy accessibility, and the low cost compared to other imaging modalities [4]
The uterine contractions occurred in 18.6% of the Magnetic resonance imaging (MRI) scans during 14–18 weeks gestational age (GA) and 26.5% of the MRI scans during 19–24 weeks GA
We investigated uterine motion during MRI acquisition in normal human pregnancy at early gestation, characterized by MRI-based motion tracking

Summary

Introduction

Placental function and growth are critically important to fetal health and development [1,2,3].Ultrasound is the primary technique for imaging the fetus and placenta primarily due to its proven utility, easy accessibility, and the low cost compared to other imaging modalities [4]. Placental function and growth are critically important to fetal health and development [1,2,3]. The limitations of ultrasound include low soft-tissue contrast, small field of view (cannot measure placental volume), and poor image quality in some placental functional imaging, which makes ultrasound findings potentially inconclusive or insufficient to guide treatment options [5,6]. MRI is a promising technique for fetal and placental imaging because it provides excellent soft-tissue contrast, functional imaging, and no ionizing radiation [7,8]. Diagnostics 2020, 10, 840 remains one of the major limiting factors for functional placenta and fetal imaging [9,10] as MRI is sensitive to motion artifacts due to a long acquisition time. There is a limited understanding of the uterine motion, in early gestation, and characterization of the uterine motion would be important to allow developing strategies to minimize motion-related MRI artifacts

Objectives

Methods

Results

Discussion

Conclusion