Chiari malformation type III is a rare congenital anomaly. It consists of the posterior fossa contents herniation through an occipital or high cervical encephalocele sac. Although it has traditionally been associated with a high mortality rate, the absence of certain poor prognostic factors and appropriate medical and surgical treatment allow these children to survive and have a remarkable initial functional improvement. Surgical goals are defect repair, preservation of viable brain tissue, adequate skin coverage and hydrocephalus management. Despite all of this, the tendency of these newborns is to maintain a significant disability and if they present poor prognostic criteria, they usually demise within a short period of time. We report the case of a newborn with Chiari malformation type III diagnosed during pregnancy. After characterizing the anomaly with a postnatal MRI, the encephalocele was excised and multi-layer closure was performed. The patient progressively developed hydrocephalus during the postoperative period and required ventriculoperitoneal shunt placement. After an initial uneventful course, our patient suffered several episodes of respiratory disturbances. The child became ventilator dependent and palliative care was established in agreement with the parents after ruling out shunt malfunction.

The diagnosis of corpus callosum anomalies by prenatal ultrasound has improved over the last decade because of improved imaging techniques, scanning skills, and the routine implementation of transvaginal neurosonography.
Our aim was to investigate all cases of incomplete agenesis of the corpus callosum and to report the sonographic characteristics, the associated anomalies, and the perinatal outcomes.
We performed a retrospective analysis of cases from January 2007 to December 2017 with corpus callosum anomalies, either referred for a second opinion or derived from the prenatal ultrasound screening program in a single tertiary referral center. Cases with complete agenesis were excluded from the analysis. Standardized investigation included a detailed fetal ultrasound including neurosonogram, fetal karyotyping (standard karyotype or array comparative genomic hybridization) and fetal magnetic resonance imaging. The pregnancy outcome was collected, and pathologic investigation in case of termination of the pregnancy or fetal or neonatal loss was compared with the prenatal findings. The pregnancy and fetal or neonatal outcomes were reported. The neurologic assessment was conducted by a pediatric neurologist using the Bayley Scales of Infant Development-II and the standardized Child Development Inventory when the Bayley investigation was unavailable.
Corpus callosum anomalies were diagnosed in 148 cases during the study period, 62 (41.9%) of which were excluded because of complete agenesis, and 86 fetuses had partial agenesis (58.1%). In 20 cases, partial agenesis (23.2%) was isolated, whereas 66 (76.7%) presented with different malformations among which 29 cases (43.9%) were only central nervous system lesions, 21 cases (31.8%) were non-central nervous system lesions, and 16 cases (24.3%) had a combination of central nervous system and non-central nervous system lesions. The mean gestational age at diagnosis for isolated and non-isolated cases was comparable (24.29 [standard deviation, 5.05] weeks and 24.71 [standard deviation, 5.35] weeks, respectively). Of the 86 pregnancies with partial agenesis, 46 patients opted for termination of the pregnancy. Neurologic follow-up data were available for 35 children. The overall neurologic outcome was normal in 21 of 35 children (60%); 3 of 35 (8.6%) showed mild impairment and 6 of 35 (17.1%) showed moderate impairment. The remaining 5 of 35 (14.3%) had severe impairment. The median duration of follow-up for the isolated form was 45.6 months (range, 36-52 months) and 73.3 months (range, 2-138 months) for the nonisolated form.
Partial corpus callosum agenesis should be accurately investigated by neurosonography and fetal magnetic resonance imaging to describe its morphology and the associated anomalies. Genetic anomalies are frequently present in nonisolated cases. Efforts must be taken to improve ultrasound diagnosis of partial agenesis and to confirm its isolated nature to enhance parental counseling. Although 60% of children with prenatal diagnosis of isolated agenesis have a favorable prognosis later in life, they often have mild to severe disabilities including speech disorders at school age and behavior and motor deficit disorders that can emerge at a later age.

The 22q11.2 deletion syndrome (22q11.2 DS) is known as the most common microdeletion syndrome. Due to its variable clinical phenotype, prenatal diagnosis can be challenging. The aim of this retrospective study was to evaluate the clinical course and pregnancy outcome of cases with prenatally diagnosed 22q11.2 deletion syndrome (DS) as well as to evaluate the role of prenatal magnetic resonance imaging (MRI) and postmortem examination. In total, 21 cases who underwent prenatal ultrasound examination and pregnancy care at the Department of Obstetrics and Gynecology at the Medical University of Vienna between 2012 and 2022 were included. The majority of the cases were genetically diagnosed using fluorescent in situ hybridization (FISH). The median gestational age (GA) at genetic diagnosis was 23.0 weeks (IQR 21.4-24.8 weeks). CHDs were detected in all fetuses and the most common extracardiac manifestation was thymus hypo/aplasia followed by genitourinary anomalies. Prenatal magnetic resonance imaging (MRI) revealed additional diagnostic information in three of ten cases. Overall, 14 patients opted for drug-induced TOP, of which 9 cases had a feticide prior to the induction of labor. The majority of craniofacial malformations were only detected by autopsy. In conclusion, the majority of cases prenatally diagnosed with 22q11.2 DS had an absent or hypoplastic thymus noted antenatally in addition to the detected CHD, and almost half of the cases had another extracardiac malformation of predominantly genitourinary origin. Furthermore, prenatal MRIs confirmed previously detected malformations, but only provided additional diagnostic information in three out of ten cases, whereas postmortem examination diagnosed most of the craniofacial anomalies and should always be conducted, serving as an important quality indicator for prenatal imaging.

UNASSIGNED: There are known complications for fetuses after infection with SARS-CoV-2 during pregnancy. However, previous studies of SARS-CoV-2 in pregnancy have largely been limited to histopathologic studies of placentas and prenatal studies on the effects of different SARS-CoV-2 variants are scarce to date. To examine the effects of SARS-CoV-2 variants on the placenta and fetus, we investigated fetal and extra-fetal structures using prenatal MRI.
UNASSIGNED: For this prospective case-control study, two obstetric centers consecutively referred pregnant women for prenatal MRI after confirmed SARS-CoV-2 infection. Thirty-eight prenatal MRI examinations were included after confirmed infection with SARS-CoV-2 and matched 1:1 with 38 control cases with respect to sex, MRI field strength, and gestational age (average deviation 1.76 ± 1.65, median 1.5 days). Where available, the pathohistological examination and vaccination status of the placenta was included in the analysis. In prenatal MRI, the shape and thickness of the placenta, possible lobulation, and vascular lesions were quantified. Fetuses were scanned for organ or brain abnormalities.
UNASSIGNED: Of the 38 included cases after SARS-CoV-2 infection, 20/38 (52.6%) were infected with pre-Omicron variants and 18/38 (47.4%) with Omicron. Prenatal MRIs were performed on an average of 83 days (±42.9, median 80) days after the first positive PCR test. Both pre-Omicron (P = .008) and Omicron (P = .016) groups showed abnormalities in form of a globular placenta compared to control cases. In addition, placentas in the pre-Omicron group were significantly thickened (6.35, 95% CI .02-12.65, P = .048), and showed significantly more frequent lobules (P = .046), and hemorrhages (P = .002). Fetal growth restriction (FGR) was observed in 25% (n = 5/20, P = .017) in the pre-Omicron group.
UNASSIGNED: SARS-CoV-2 infections in pregnancy can lead to placental lesions based on vascular events, which can be well visualized on prenatal MRI. Pre-Omicron variants cause greater damage than Omicron sub-lineages in this regard.
UNASSIGNED: Vienna Science and Technology Fund.

OBJECTIVE: This study aimed to present the contribution of prenatal magnetic resonance imaging (MRI) in the diagnosis of fetuses that were previously identified as isolated mild and moderate cerebral ventriculomegaly (VM) by ultrasound (US).
METHODS: The data between February 2013 and August 2020 were collected for women who were diagnosed with isolated mild or moderate fetal VM by US and subsequently underwent a fetal MRI.
RESULTS: Among 321 women, 21 (6.5%) had a clinically important additional finding after MRI. Twelve of 276 (4.3%) fetuses with mild VM and 9 of 45 (20%) with moderate VM had turned out to have additional central nervous system abnormalities. Additional findings were detected more in fetuses with moderate VM, mothers with an anterior-located placenta, and mothers with higher body mass indexes (BMIs) with statistical significance (p = 0.001, p = 0.013, p = 0.036, respectively). The most common additional MRI finding was grade 3 or 4 germinal matrix hemorrhage, which was detected in 11 of 21 fetuses (52.3%).
CONCLUSIONS: Considering the countries\' health policies, prenatal MRI would contribute mostly to the diagnosis of fetuses with moderate VM, pregnancies with anterior-located placenta, and mothers with high BMIs. According to our data, we believe that MRI will be valuable, especially in the diagnosis of grade 3 and 4 intracranial hemorrhage group.

Congenital mesoblastic nephroma (CMN) is a rare tumor, yet it is the most frequently diagnosed renal neoplasm in the first 3 months of life. CMN reports with prenatal magnetic resonance imaging (MRI) are scarce. Our aims were to describe a case with fetal MR imaging along with other findings, and to review the literature concerned with prenatal MRI detection of CMN. Upon routine ultrasound (US) examination of a 36-week pregnant woman, a fetal abdominal mass was disclosed. Prenatal MRI revealed a large, well-circumscribed renal mass of solid and cystic components, not invading the adjacent tissues, but compressing normal renal parenchyma of the lower pole of the left kidney. Thus, a low malignant renal tumor was considered. After Cesarean delivery, imaging including US and computerized tomography (CT) scan was performed on the apparently healthy boy and verified the prenatal MRI finding. Accordingly, left nephrectomy was performed at the age of 12 days. The pathology confirmed CT results of the solid and cystic components of the mass, in addition to the necrotic and hemorrhagic constitution. Cellular CMN was diagnosed, and ETV6 gene rearrangement was demonstrated by FISH analysis. No recurrence was detected within the 40 months follow-up after the operation. Our report described a rare and seldomly detected renal tumor in utero with the aid of MRI and reviewed the few related reports in the literature in which MRI was performed prenatally. This report also highlights the need for prenatal MRI as a complementary tool to US in cases with suspected fetal renal mass and recommends its use for carefully managing the possible risks during the perinatal period.

The aim of this cohort study was to describe and analyze the surgical treatment and outcome of posterior fossa arachnoid cysts (PFACs) in infants.
Patients presenting with a PFAC at infancy or prenatally, between the years 2000 and 2019, and who were surgically treated before the age of 2 years, were included in this study. Patient data were retrospectively collected including baseline characteristics and surgical variables. Factors related to revision surgery were analyzed through uni- and multivariate analysis.
Thirty-five patients, of whom 54.3% were male, were included. The cyst was diagnosed prenatally in 23 patients (65.7%). Surgery was typically recommended after a mean cyst follow-up of 3.4 ± 3.9 months, with a mean age at surgery of 6.1 ± 5.1 months. In 54.3% of patients (n = 19), surgery was performed before the age of 6 months. The PFAC was treated purely neuroendoscopically in 57.1% of patients (n = 20), while 28.6% of patients underwent open cyst procedures (n = 10), 5.7% (n = 2) were treated with a shunt, and 8.6% (n = 3) underwent a combined procedure. Additional surgery was required in 31.4% of patients (n = 11; mean 2.36 ± 2.11 surgeries per patient). At the last follow-up (61.40 ± 55.33 months), no mortality or permanent morbidity was seen; radiological improvement was apparent in 83.9% of the patients. Those patients treated before the age of 6 months (p = 0.09) and who presented before surgery with a stable cyst size that was maintained throughout preoperative monitoring (p = 0.08) showed a trend toward higher revision rates after surgical treatment.
PFACs in infancy may require surgical treatment before the age of 6 months. Navigated endoscopy was a valid surgical option. Overall mortality or permanent morbidity was rare. Additional surgery was required in up to 30% of the patients; younger age and a preoperatively stable cyst might be risk factors for revision surgery.

BACKGROUND: Congenital pulmonary airway malformations (CPAM), bronchopulmonary sequestrations (BPS), and CPAM-BPS hybrid lesions are most commonly solitary; however, >1 lung congenital lung lesion may occur.
OBJECTIVE: To assess the frequency of multiple congenital thoracic anomalies at a high-volume referral center; determine prenatal ultrasound (US) and magnetic resonance imaging (MRI) features of these multifocal congenital lung lesions that may allow prenatal detection; and determine the most common distribution or site of origin.
METHODS: Database searches were performed from August 2008 to May 2019 for prenatally evaluated cases that had a final postnatal surgical diagnosis of >1 congenital lung lesion or a lung lesion associated with foregut duplication cyst (FDC). Lesion location, size, echotexture, and signal characteristics were assessed on prenatal imaging and correlated with postnatal computed tomographic angiography and surgical pathology. -Results: Of 539 neonates that underwent surgery for a thoracic lesion, 35 (6.5%) had >1 thoracic abnormality. Multiple discrete lung lesions were present in 19 cases, and a lung lesion associated with an FDC was present in 16. Multifocal lung lesions were bilateral in 3 cases; unilateral, multilobar in 12; and, unilobar multisegmental in 4. Median total CPAM volume/head circumference ratio for multifocal lung lesions on US was 0.66 (range, 0.16-1.80). Prenatal recognition of multifocal lung lesions occurred in 7/19 cases (36.8%). Lesion combinations were CPAM-CPAM in 10 cases, CPAM-BPS in 5, CPAM-hybrid in 2, hybrid-hybrid in 1, and hybrid-BPS in 1. Of 5 unilateral, multifocal lung lesions, multifocality was prenatally established through identification of a band of normal intervening lung or intrinsic differences in lesion imaging features.
CONCLUSIONS: Although less common, multiple thoracic abnormalities can be detected prenatally. Of multifocal lung lesions, the most common combination was CPAM-CPAM, with a unilateral, multilobar distribution. Prenatal recognition is important for pregnancy counseling and postnatal surgical management.

OBJECTIVE: To document the imaging findings suggestive of anorectal malformation (ARMs) on prenatal US and MRI.
METHODS: Retrospective evaluation of the screening US and prenatal MRI exams of the rectum and ano-perineal region in normal fetuses and in patients with ARMs.
RESULTS: Examples showing the normal rectal and anoperineal anatomy on prenatal US and MRI exams and the imaging findings observed in different types of confirmed ARMS.
CONCLUSIONS: Prenatal diagnosis of ARMs requires both a systematic evaluation of the fetal pelvis and perineum and an appropriate knowledge of its suggestive imaging findings.

BACKGROUND: Prenatal magnetic resonance imaging is the best tool to visualize foetal airway.
OBJECTIVE: To evaluate the performance of MRI in the assessment of foetal airway status in the presence of a neck mass.
METHODS: Two paediatric radiologists with 12- and 2-year experience in foetal imaging retrospectively analysed 23 foetal MRI examinations, performed between 2001 and 2016, after a second-level ultrasound suspicious for presence of a neck mass. Postnatal imaging, postoperative report, histology, autopsy, and clinical outcomes were the reference standard to calculate sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of prenatal MRI in detecting airway patency. We used the Cohen к statistics to estimate the interobserver agreement. We also assessed MRI performance in the diagnosis of the mass nature.
RESULTS: We obtained data about postnatal airway status in 19 of 23 patients; prenatal MRI demonstrated a sensitivity of 9/9 [100%, 95% confidence interval (CI) 66-100%], specificity 8/10 (80%, 44-98%), accuracy 17/19 (89%, 67-99%), PPV 9/11 (82%, 48-98%), and NPV 8/8 (100%, 63-100%); the interobserver agreement was perfect. Prenatal MRI correctly identified 21 of 23 masses (к = 0.858); the interobserver agreement was almost perfect (к = 0.851).
CONCLUSIONS: Prenatal MRI demonstrated high accuracy in assessing foetal airway status and diagnosing mass nature, allowing proper delivery planning.