UNASSIGNED: This study aimed to compare the ultrasound (USG) and fetal magnetic resonance imaging (MRI) findings in the evaluation of congenital fetal anomalies and to determine whether the management is changes significantly if MRI is combined with USG.
UNASSIGNED: In this prospective observational cohort study, we performed fetal MRI in 90 consecutive cases of fetuses diagnosed or suspected as having congenital anomalies on a prior level II USG scan. We then compared the USG and MRI findings of each anomaly according to the diagnostic information yielded by each modality.
UNASSIGNED: Of 90 fetuses examined during 1 year study period, MRI and USG findings were equivalent in 13.3% of cases. MRI provided additional information in 68.8% cases, of which pregnancy management was changed in 5.6% cases. MRI provided additional information but did not change management in 63.3% of cases. USG provided additional information but did not change pregnancy management in 17.8% of cases. The difference was statistically significant with a p value of .000.
UNASSIGNED: Fetal MRI is a significantly better modality than USG for detecting additional findings in anomalies of specific organ systems. Because of its high diagnostic yield for central nervous system (CNS) anomalies, it can be combined with USG for this subgroup. For non-CNS anomalies of genitourinary system, thorax, or in syndromic/complex malformations/conjoint twin pregnancy, it may be used as an adjunct to USG on a case to case basis. MRI has the potential to change the pregnancy management in few cases, but benefit is small to advocate a complete integration of MRI and USG for fetal anomaly scanning at present.

BACKGROUND: The detection of absent septi pellucidi (ASP) during obstetric ultrasound is a rare event. However, the clinical implications of this finding are significant. ASP can be associated with severe central nervous system anomalies such as holoprosencephaly, agenesis/dysgenesis of the corpus callosum, schizencephaly, severe ventriculomegaly, and open neural tube defects. In such cases, the prognosis is poor. When no such anomalies are identified, isolated ASP usually carries a good prognosis. However, some fetuses thought to have isolated ASP actually have septo-optic dysplasia (SOD), which is associated with optic nerve hypoplasia, hypothalamic-pituitary dysfunction, and developmental delay.
METHODS: A case in which fetal 3.0 Tesla magnetic resonance imaging (MRI) was considered crucial to definitively diagnose isolated ASP is presented. A review of the literature was conducted and analyzed to determine the role of MRI in the evaluation of fetuses with ASP, with special consideration on the differential diagnosis between isolated ASP and SOD.
CONCLUSIONS: Differentiating isolated ASP from SOD is imperative for adequate prenatal counseling. Unfortunately, making a prenatal diagnosis of SOD requires visualization and evaluation of the fetal optic nerves, chiasm, and pituitary gland, which is very demanding and not always possible using ultrasound. Fetal MRI has the potential of obtaining high-quality images of the fetal brain, and therefore this technique can be used for establishing the differential diagnosis in utero.

OBJECTIVE: The aim of this study was to report the rate of additional anomalies detected exclusively at prenatal magnetic resonance imaging (MRI) in fetuses with isolated severe ventriculomegaly undergoing neurosonography.
METHODS: Multicenter, retrospective, cohort study involving 20 referral fetal medicine centers in Italy, United Kingdom, Spain and Denmark. Inclusion criteria were fetuses affected by isolated severe ventriculomegaly (≥15 mm), defined as ventriculomegaly with normal karyotype and no other additional central nervous system (CNS) and extra-CNS anomalies on ultrasound. In all cases, a multiplanar assessment of fetal brain as suggested by ISUOG guidelines on fetal neurosonography had been performed. The primary outcome was the rate of additional CNS anomalies detected exclusively at fetal MRI within two weeks from neurosonography. Subgroup analyses according to gestational age at MRI (RESULTS: 187 fetuses with a prenatal diagnosis of isolated severe ventriculomegaly on neurosonography were included in the analysis. Additional structural anomalies were detected exclusively at prenatal MRI in 18.1% of cases. When considering the type of anomaly, malformations of cortical development were detected on MRI in 32.4% cases, while midline or acquired (hypoxemic/hemorrhagic) lesions were detected in 26.5% and 14.7% of cases, respectively. There was no difference in the rate of additional anomalies when stratifying the analysis according to either gestational age at MRI or laterality of the lesion. At multivariate logistic regression analysis, the presence of additional anomalies only found at MRI was significantly higher in bilateral compared versus unilateral ventriculomegaly (OR: 4.37, 95% CI 1.21-15.76; p = 0.04), while neither maternal body mass index, age, severity of ventricular dilatation, interval between ultrasound and MRI, nor gestational age at MRI were associated with the likelihood of detecting associated anomalies at MRI.
CONCLUSIONS: The rate of associated anomalies detected exclusively at prenatal MRI in fetuses with isolated severe ventriculomegaly is lower than previously reported, but higher compared to isolated mild and moderate ventriculomegaly. Fetal MRI should be considered as a part of the prenatal assessment of fetuses presenting with isolated severe ventriculomegaly at neurosonography.

To assess the performance of fetal magnetic resonance imaging (MRI) in detecting associated anomalies in fetuses diagnosed with isolated corpus callosal (CC) anomaly on multiplanar ultrasound evaluation of the fetal brain (neurosonography).
This was a multicenter, retrospective cohort study involving 14 fetal medicine centers in Italy, UK, Portugal, Canada, Austria and Spain. Inclusion criteria were fetuses with an apparently isolated CC anomaly, defined as an anomaly of the CC and no other additional central nervous system (CNS) or extra-CNS abnormality detected on expert ultrasound, including multiplanar neurosonography; normal karyotype; maternal age ≥ 18 years; and gestational age at diagnosis ≥ 18 weeks. The primary outcome was the rate of additional CNS abnormalities detected exclusively on fetal MRI within 2 weeks following neurosonography. The secondary outcomes were the rate of additional abnormalities according to the type of CC abnormality (complete (cACC) or partial (pACC) agenesis of the CC) and the rate of additional anomalies detected only on postnatal imaging or at postmortem examination.
A total of 269 fetuses with a sonographic prenatal diagnosis of apparently isolated CC anomalies (207 with cACC and 62 with pACC) were included in the analysis. Additional structural anomalies of the CNS were detected exclusively on prenatal MRI in 11.2% (30/269) of cases, with malformations of cortical development representing the most common type of anomaly. When stratifying the analysis according to the type of CC anomaly, the rate of associated anomalies detected exclusively on MRI was 11.6% (24/207) in cACC cases and 9.7% (6/62) in pACC cases. On multivariate logistic regression analysis, only maternal body mass index was associated independently with the likelihood of detecting associated anomalies on MRI (odds ratio, 1.07 (95% CI, 1.01-1.14); P = 0.03). Associated anomalies were detected exclusively after delivery and were missed on both types of prenatal imaging in 3.9% (8/205) of fetuses with prenatal diagnosis of isolated anomaly of the CC.
In fetuses with isolated anomaly of the CC diagnosed on antenatal neurosonography, MRI can identify a small proportion of additional anomalies, mainly malformations of cortical development, which are not detected on ultrasound. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Fetal tumors are rare and usually followed by poor outcome. We describe our single-center experience with fetal tumors evaluated by ultrasound and magnetic resonance imaging (MRI). Our aims were to evaluate mortality and morbidity including long-term outcome and to determine which ultrasound and MRI characteristics were helpful for pre- and perinatal management.
We conducted a retrospective analysis on prenatally diagnosed tumors between 1998 and 2018. Poor outcome included fetal or neonatal death and survival with serious illness. MRI addressed tumor morphology (sacrococcygeal teratomas), compromise of surrounding structures (head and neck tumors) and early depiction of brain alterations specific to tuberous sclerosis (rhabdomyomas).
Of 68 pregnancies, 15 (22%) were terminated and eight children (8/53, 15%) died pre- or postnatally. Of the 45 survivors (45/68, 66%), 24 (24/45, 53%) were healthy, eight (8/45, 18%) had a minor illness and 13 (13/45, 29%) a serious illness. Diffusion- and T1-weighted MRI reliably predicted tumor morphology in teratomas. To detect head and neck tumors critical to airway obstruction, MRI was superior to ultrasound in delivery planning. Rhabdomyomas were frequently associated with tuberous sclerosis, regardless of their number or size in ultrasound; MRI could depict specific brain alterations from the early third trimester onwards. For several rare tumors, MRI provided critical differential diagnoses that could not be clearly displayed in ultrasound.
The rate of survivors with serious long-term illness among fetuses with prenatal diagnosis of a tumor was high. MRI is specifically helpful for risk stratification in fetal teratomas and delivery planning in head and neck tumors.

To assess the role of fetal magnetic resonance imaging (MRI) in detecting associated anomalies in fetuses presenting with mild or moderate isolated ventriculomegaly (VM) undergoing multiplanar ultrasound evaluation of the fetal brain.
This was a multicenter, retrospective, cohort study involving 15 referral fetal medicine centers in Italy, the UK and Spain. Inclusion criteria were fetuses affected by isolated mild (ventricular atrial diameter, 10.0-11.9 mm) or moderate (ventricular atrial diameter, 12.0-14.9 mm) VM on ultrasound, defined as VM with normal karyotype and no other additional central nervous system (CNS) or extra-CNS anomalies on ultrasound, undergoing detailed assessment of the fetal brain using a multiplanar approach as suggested by the International Society of Ultrasound in Obstetrics and Gynecology guidelines for the fetal neurosonogram, followed by fetal MRI. The primary outcome of the study was to report the incidence of additional CNS anomalies detected exclusively on prenatal MRI and missed on ultrasound, while the secondary aim was to estimate the incidence of additional anomalies detected exclusively after birth and missed on prenatal imaging (ultrasound and MRI). Subgroup analysis according to gestational age at MRI (< 24 vs ≥ 24 weeks), laterality of VM (unilateral vs bilateral) and severity of dilatation (mild vs moderate VM) were also performed.
Five hundred and fifty-six fetuses with a prenatal diagnosis of isolated mild or moderate VM on ultrasound were included in the analysis. Additional structural anomalies were detected on prenatal MRI and missed on ultrasound in 5.4% (95% CI, 3.8-7.6%) of cases. When considering the type of anomaly, supratentorial intracranial hemorrhage was detected on MRI in 26.7% of fetuses, while polymicrogyria and lissencephaly were detected in 20.0% and 13.3% of cases, respectively. Hypoplasia of the corpus callosum was detected on MRI in 6.7% of cases, while dysgenesis was detected in 3.3%. Fetuses with an associated anomaly detected only on MRI were more likely to have moderate than mild VM (60.0% vs 17.7%; P < 0.001), while there was no significant difference in the proportion of cases with bilateral VM between the two groups (P = 0.2). Logistic regression analysis showed that lower maternal body mass index (adjusted odds ratio (aOR), 0.85 (95% CI, 0.7-0.99); P = 0.030), the presence of moderate VM (aOR, 5.8 (95% CI, 2.6-13.4); P < 0.001) and gestational age at MRI ≥ 24 weeks (aOR, 4.1 (95% CI, 1.1-15.3); P = 0.038) were associated independently with the probability of detecting an associated anomaly on MRI. Associated anomalies were detected exclusively at birth and missed on prenatal imaging in 3.8% of cases.
The incidence of an associated fetal anomaly missed on ultrasound and detected only on fetal MRI in fetuses with isolated mild or moderate VM undergoing neurosonography is lower than that reported previously. The large majority of these anomalies are difficult to detect on ultrasound. The findings from this study support the practice of MRI assessment in every fetus with a prenatal diagnosis of VM, although parents can be reassured of the low risk of an associated anomaly when VM is isolated on neurosonography. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Fetal lung masses are rare findings in prenatal ultrasound scanning in general population, of which congenital cystic adenomatoid malformation is the most commonly diagnosed type. This paper reports a single case of congenital cystic adenomatoid malformation detected at our hospital and the subsequent clinical follow-up using ultrasound scanning and fetal magnetic resonance imaging.