Utilization of 3-T fetal magnetic resonance imaging in clinical practice: a single-institution experience.

Abstract

As the safety and efficacy of fetal magnetic resonance imaging (MRI) at 3 tesla (T) continues to evolve, understanding its potential benefits and limitations is becoming increasingly important. We aim to compare the image quality of fetal MRI between 1.5T and 3T in routine clinical practice. Fetal MRIs performed at 3T between Jan. 1, 2019, and Dec. 31, 2019, at our institution were retrospectively reviewed by four fellowship-trained subspecialty radiologists. Imaging quality by system, sequence and artifacts were compared with matched controls at 1.5T and rated using a modified Likert scale. Thirty-three fetal MRIs at 3T were reviewed, and a control group of studies for the same clinical indication and equivalent gestational age were selected for comparison. Two of the four radiologists preferred 3-T image quality of the brain with slight agreement among the four reviewers (k=0.19, P=0.01). Three of the four radiologists had no preference for 1.5T vs. 3T in the majority of cases in evaluating the chest and abdomen. In the overall assessment, 3T was preferred in less than half of cases by all four radiologists (k=0.07, P=0.26). In the evaluation of standing wave, moire fringe and magnetic susceptibility artifacts, 3T was not preferred in the majority of studies by all four radiologists. Total exam time was significantly longer in the 3-T fetal MRIs (75.0±15.1min) compared to the 1.5-T fetal MRIs (55.5±13.3min, P<0.001). While 3T is a feasible alternative to 1.5T for fetal MRI, the increased artifacts and longer exam times observed at 3T without clear improvement in overall image quality make 1.5T preferable for fetal MRI in routine clinical practice.