Three-dimensional reconstruction of fetal abnormalities using ultrasonography and magnetic resonance imaging.

Objective: We aimed to compare three-dimensional (3D) fetal malformation images obtained using ultrasonography (US) and magnetic resonance imaging (MRI) on the same day during the third trimester of pregnancy. Methods: Total 33 fetuses were selected from cases evaluated for malformations. Morphological abnormalities were first scanned using 3DUS. MRI was used to confirm the previous preliminary 3DUS findings, and diagnoses were confirmed postnatally. 3DUS scans were performed transabdominally using an Rab (4-8 L) probe, Voluson 730 Pro/Expert and E8 (General Electric, Healthcare, Zipf, Austria). MRI was performed using a 1.5-T scanner (Magneton Avanto, Siemens, Erlangen, Germany) with a body coil. The 3D reconstruction of the structure of interest was manually performed from a True FISP sequence using an interactive pen tablet (Syngo multimodality 2009B, Siemens, Erlangen, Germany). Results: Despite recent advancements in 3DUS, the quality of 3D images obtained from MRI was superior during the third trimester. 3DUS had certain limitations, such as being influenced by the fetal position, the volume of amniotic fluid, and maternal obesity. Fetal movements during image acquisition were one of the main challenges for MRI. Conclusion: The quality of the 3D images obtained using MRI was superior to that of images obtained using US during the third trimester of pregnancy.