OC22.02: An evaluation of real‐time MR single shot fast spin echo imaging in visualization of fetal midline corpus callosum and secondary palate

Abstract

Objective: To evaluate the adjunct value of diffusion-weighted MRI (DW-MRI) in intrauterine assessment of foetal pathology inand outside of the brain. Methods: MRI was performed in a consecutive series of 50 pregnant women, mean age 28 years, diagnosed with abnormal ultrasonographic findings of the foetus, suggestive of either a spaceoccupying lesion in thorax or abdomen, or neurologic abnormalities. The MRI protocol consisted of snapshot T1and T2-weighted imaging and DW-MRI. DW-MRI was performed using a large range of b-values (0–1000 sec/mm). Apparent diffusion coefficient (ADC) values were calculated using all b-values, allowing for maximal accuracy in determination of these values. The findings of these measurements were analyzed and interpreted together with the tissue characteristics of the pathologic tissues derived from the plain T1-and T2-weighted measurements. Comparisons were made with histopathology where available. Results: Whereas T1and T2-weighted MRI clearly allowed for lesional description (solid tissue, cystic mass, tissue edema, etc), analysis of the DW-MRI and calculation of the ADC values allowed for more detailed diagnostic assumptions regarding ischemic events, lesion cellularity and vessel density, multiplication rate in serial studies and gross methemoglobine content in cases of hemorrhage. Conclusions: Diffusion-weighted images can be used routinely in addition to a standard protocol of fetal MRI that consists of T1 and T2 weighted images. It offers important supplementary information beyond a mere morphologic description that can lead to relevant prenatal diagnostic refinement and improved therapy planning.