Post-mortem high-field magnetic resonance imaging: effect or various factors

Purpose: To evaluate image quality and diagnostic accuracy of high-field post-mortem (PM) magnetic resonance imaging (MRI) on fetuses below 20 weeks of gestation before and after the freeze-thaw process. Materials and methods: Nine fetuses were scanned with three different scanning procedures: "fresh'', just after termination of pregnancy (TOP), "non-fresh short scan'' and "non-fresh long scan'' after being kept at -20 degrees C, followed by a conventional autopsy. The brain, thorax except the heart, heart and abdomen were studied. The qualities of the images for the four different fetal regions and for the three different scanning procedures were reported. Regression analysis was used to investigate the effect on image quality of different factors. Additionally, the diagnostic accuracy was also evaluated. Results: Fetuses at 12.0-19.6 weeks were included. Regression analysis showed that better image quality was correlated to advanced gestation at TOP and scan on fresh fetuses. PM-MRI on fresh fetuses was always diagnostic for the brain and in more than half of cases on non-fresh fetuses and was nearly equally diagnostic for thoracic and abdominal structures. Conclusion: High-field PM-MRI seems to offer a quite reliable alternative to the parents declining conventional PM for fetuses before 20 weeks whether these fetuses are freshly scanned or after being frozen.