Double Aortic Arch: A Comparison of Fetal CMR, Postnatal CT and Surgical Findings.

BACKGROUND: In double aortic arch (DAA) one of the arches can demonstrate atretic portions postnatally, leading to diagnostic uncertainty due to overlap with isolated right aortic arch (RAA) variants. The main objective of this study is to demonstrate the morphological evolution of different DAA phenotypes from prenatal to postnatal life using 3D fetal cardiac magnetic resonance imaging (CMR) and postnatal CT/CMR imaging. METHODS: 3D fetal CMR was undertaken in fetuses with suspected DAA over a six-year period (Jan 2016 - Jan 2022). All cases with surgical confirmation of DAA were retrospectively studied and morphology on fetal CMR was compared to postnatal CT/CMR and surgical findings. RESULTS: 32 fetuses with surgically confirmed DAA underwent fetal CMR. All demonstrated a complete DAA with left-sided arterial duct. The RAA was dominant in 30/32 (94%). Postnatal CT/CMR was undertaken at median age of 3.3months (IQR 2.0-3.9) demonstrating DAA with patency of both arches in 9/32 (28%), with 6 showing signs of coarctation of the left aortic arch (LAA). The LAA isthmus was not present on CT/CMR in 22/32(69%), the transverse arch between left carotid and left subclavian artery was not present in 1 case. CONCLUSIONS: Fetal CMR provides novel insights into perinatal evolution of DAA. The smaller LAA can develop coarctation or atresia related to postnatal constriction of the arterial duct, making diagnosis of DAA challenging with contrast-enhanced CT/CMR. This highlights the potentially important role for prenatal 3D vascular imaging and might improve intepretation of postnatal imaging.

Abdominal Ultrasound Scanning for NEC in Babies at the Threshold of Viability: A Single Centre Experience.

AIM: Neonatal units are caring for increasing numbers of babies born <24 weeks gestation. These babies are vulnerable to developing necrotising enterocolitis (NEC). Their presentation is often atypical, both clinically and radiologically. Optimal diagnostic strategies are not yet known. We report our experience of abdominal ultrasound scanning (AUSS) to clarify its role. METHODS: All babies in a single neonatal surgical centre born <24 weeks gestation undergoing AUSS for suspected NEC from January 2015 to January 2023 were included. We compared abdominal ultrasound findings with plain radiographs and correlated these to intraoperative findings. RESULTS: Thirty-nine babies born <24 weeks gestation were diagnosed with NEC during the study period, and of these seventeen had an AUSS and formed the study cohort. Twelve underwent laparotomy at which NEC was confirmed, and the remaining five were managed non-operatively. Abdominal radiograph findings were: Paucity of gas (12), gaseous dilatation (2), paucity of gas with proximal dilatation (1), pneumatosis (1), and lucencies over the liver (1). In twelve cases who underwent surgery, AUSS findings were (more than one possible): Complex ascites (6), inflamed bowel (4), aperistaltic bowel (3), mass/collection (4), pneumatosis (1). All had NEC confirmed at laparotomy. In five cases who did not progress to surgery, findings were: Simple free fluid (2), pneumatosis (2), inflamed bowel (1), aperistaltic bowel (1). None of these cases subsequently underwent surgery or died of complications of NEC. CONCLUSION: AUSS is a useful imaging modality for NEC in babies born <24 weeks gestation. It can reliably identify babies who would benefit from surgery. TYPE OF STUDY: Retrospective cohort study.

Single-center review on safety of biodegradable airway stenting in pediatric population.

BACKGROUND: Tracheobronchomalacia (TBM) and airway stenosis are recognized etiologies of airway obstruction among children. Their management is often challenging, requiring multiple interventions and prolonged respiratory support with associated long-term morbidity. Metallic or silicone stents have been used with mixed success and high complication rates. More recently biodegradable Ella stents (BES) provided an attractive interventional option. OBJECTIVES: We report our experience in the treatment of TBM and vascular airway compression using BES. We deliberately downsized them to minimize intraluminal granulation tissue formation. MATERIALS AND METHODS: Retrospective study over an 8-year period between November 2012 and December 2020 of pediatric patients with severe airway obstruction requiring airway stenting for extubation failure, malacic death spells, recurrent chest infections, or lung collapse. RESULTS: Thirty-three patients (5 tracheal and 28 bronchial diseases) required 55 BES during the study period. The smallest patient weighed 1.8 kg. Median age of patient at first stent implantation was 13.1 months (IQR 4.9-58.3). The majority of the bronchial stents were in the left main bronchus (93%), of which 57% for vascular compression. Repeat stents were used in 19 patients (57.7%), with a range of two to four times. We did not experience erosion, infection, or obstructive granuloma needing removal by forceps or lasering. Three stent grid occluded with secretions needing bronchoscopic lavage. Stent migration occurred in three patients. CONCLUSIONS: BES holds promise as a treatment option with low rate of adverse effects for a specific subset of pediatric patients with airway malacia or vascular compression. Further studies are warranted.

Postnatal impact of a prenatally diagnosed double aortic arch.

BACKGROUND: A double aortic arch (DAA) is increasingly identified before birth; however, there are no published data describing the postnatal outcome of a large prenatal cohort. OBJECTIVE: To describe the associations, symptoms and impact of prenatally diagnosed DAA. METHODS: Retrospective review of consecutive cases seen at two fetal cardiology units from 2014 to 2019. Clinical records including symptoms and assessment of tracheobronchial compression using flexible bronchoscopy were reviewed. Moderate-severe tracheal compression was defined as >75% occlusion of the lumen. RESULTS: There were 50 cases identified prenatally and 48 with postnatal follow-up. Array comparative genomic hybridisation (aCGH) was abnormal in 2/50 (4%), aCGH was normal in 33/50 (66%) and of those reviewed after birth, 13 were phenotypically normal. After birth, there was a complete DAA with patency of both arches in 8/48 (17%) and in 40/48 (83%) there was a segment of the left arch which was a non-patent, ligamentous connection.Stridor was present in 6/48 (13%) on the day of birth. Tracheo-oesophageal compressive symptoms/signs were present in 31/48 (65%) patients at median age of 59 days (IQR 9-182 days). Tracheal/carinal compression was present in 40/45 (88%) cases. Seven of 17 (41%) asymptomatic cases demonstrated moderate-severe tracheal compression. All morphologies of DAA caused symptoms and morphology type was not predictive of significant tracheal compression (p=0.3). CONCLUSIONS: Genetic testing should be offered following detection of double aortic arch. Early signs of tracheal compression are common and therefore delivery where onsite neonatal support is available is recommended. Significant tracheal compression may be present even in the absence of symptoms.

Current Gastrointestinal Imaging in Children.

Gastrointestinal (GI) pathologies in children present with overlapping symptoms and signs. Radiological imaging is assuming a more prominent role in the diagnostic pathway. This article is aimed primarily at paediatricians, helping them to understand and thereby better utilise radiological imaging. The strengths and weaknesses of the various imaging modalities are outlined in a concise manner. Illustrative conditions are discussed with an emphasis on key diagnostic features along with several, high quality annotated images. Emerging concepts are introduced throughout the article. These are referenced by the latest research to give the reader an update of current GI imaging in children.