Fetal MR How I do it in clinical practice M J Weston Leeds Why do it? • Add diagnostic certainty to US findings • Find additional anomalies • Research How is it done? • Trickier than you think. • Fast acquisition times • Signal to noise problems • Risk to fetus • T2 is mainstay • T1 useful for bowel and looking for fat or haemorrhage Cerebral MRI T2 weighted Other sequences T2 T1 DWI Change with time 24 weeks 36 weeks Spina bifida • MR is not a screening test • All cases detected by US • Confirmatory • Assignment of level • Visually very powerful for parents Spinal cord Conus Medullaris Spina bifida Head signs Spina bifida Sagittal US and MR are equally accurate at assigning level of lesion Aaronson OS et al. Radiology 2003; 227: 839‐843 Diastematomyelia Split cord Huge NTD on US Visual impact of MRI Caudal Regression Syndrome Caudal regression Head anomalies • Commonest indication – Apparently isolated ventriculomegaly • Establishing normal brain maturation • Problems with counselling… Unilateral hydrocephalus? • Near field reverberation Hydrocephalus Prognosis? Ventricular bleed Different sequences in bleed But, postnatally… Ultrasound Obstet Gynecol 2008; 32: 188 – 198 Good prognosis… Schizencephaly Artefact or schizencephaly? Follow-up Deep asymmetrical calcarine sulcus Arachnoid cyst Taiwan J Obstet Gynecol 2007; 46: 187 Prepontine arachnoid cyst Death of co-twin Obstet Gynecol 2011; 118: 928 – 940 Monochorionic – neurodevelopmental delay 26% of survivors Dichorionic ‐ 2% 2 weeks later Microcephaly etc Face and holoprosencephaly Face and head Facial cleft and no eyes Normal Sent for head but… But also has small lungs Problem solving Fetal kidneys Inclusion cyst Cervical teratoma Neck lymphangioma Nasopharyngeal teratoma? Focal bulge What is this? Co‐existant Mole Retroplacental bleed Intrapartum scar rupture Conclusions • Complimentary to US • Added worth is less if expert US • Prognostic difficulties • Changing the role of the Radiologist.