MRI Important Tool in Prenatal Fetal Assessment

Magnetic resonance imaging is becoming an increasingly important tool in assessing prenatal disease, according to a presentation featured in an electronic exhibit at the American Roentgen Ray Society 2015 Annual Meeting (ARRS) in Toronto, Canada.

Researchers from the Mayo Clinic and Nemours Children’s Hospital in Jacksonville, Florida, reviewed a series of fetal MRI cases for assessment of fetal anatomy and pathology to highlight the diagnostic capability of fetal MRI. No gadolinium is used for the imaging, which is done typically after 18 to 20 weeks’ gestation.

As 3T MRI scanners become more common due to their improved image signal-to-noise ratio and anatomical detail, the benefits of 3T MRI must be weighed against potential risks to the fetus that may result from the higher field strength.

The imaging was performed at the researchers’ facility; sequences were monitored in real time by a radiologist at the scanner and manipulated to determine optimal imaging planes during the scan. T2-weighted HASTE (TR/TE, 1500/60; 4-mm slice thickness) sequences are obtained in the axial, coronal, and sagittal planes with respect to the fetus.

"MRI is playing an increasingly important role in the assessment of complex prenatal disease," co-author Kathleen E. Carey, MD, said in a release. "The use of stronger 3-T field strengths may allow for improved visualization of subcutaneous fat and osseous structures, including the hands and feet of the developing fetus."

The researchers concluded that although ultrasound is still the initial imaging study for prenatal assessment of the fetus, MR imaging is playing an increasingly important role in the assessment of complex prenatal disease. “It is important to be aware of the indications and limitations of fetal MRI at 1.5-T as well as higher field strengths as the diagnostic community continues to move in the direction of 3-T,” they wrote.