Actual imaging time in fetal MRI

Area of Science:

• Radiology
• Medical Imaging
• Obstetrics

Background:

• Safety in magnetic resonance imaging (MRI), particularly fetal MRI, is crucial.
• Limited data exists on effective exposure time during fetal MRI.
• Understanding actual scan duration is vital for safety assessments.

Purpose of the Study:

• To determine the actual imaging time during fetal MRI studies.
• To quantify the proportion of time dedicated to actual scanning versus preparation.
• To provide data for more accurate estimation of fetal exposure to RF deposition and noise.

Main Methods:

• Analysis of 100 fetal MRI studies on a 1.5 T system.
• Measurement of total study duration, number of sequences, and actual imaging time.
• Calculation of actual imaging time by summing individual sequence scan times.

Main Results:

• Mean study duration was 34.6 minutes.
• Average actual scan time was 11.4 minutes, representing 33% of total study time.
• Ultrafast T2-weighted and steady-state free-precession sequences constituted 62.3% of the actual scan time.

Conclusions:

• Actual imaging time in fetal MRI is significantly less than total study duration.
• Non-imaging time includes scanner preparation, sequence planning, and patient repositioning.
• These findings aid in a more precise estimation of fetal exposure to radiofrequency energy and acoustic noise.