Ultrasound as the first line investigation for midgut malrotation: a UK tertiary centre experience.

AIM: To present the first 22-months experience of transitioning to an ultrasound-first pathway for suspected midgut malrotation. MATERIALS AND METHODS: An "ultrasound-first" imaging pathway was initiated in October 2021. Twenty-two-months later, a search was undertaken of all <1-year-old patients with "bilious", "malrotation," or "volvulus" as the imaging indication. Reports and images from upper gastrointestinal fluoroscopy (UGI) and ultrasound were reviewed, and diagnoses and outcomes were documented. RESULTS: The search yielded 101 eligible cases between October 2021 and July 2023. Of the patients, 63/101 (62%) had both ultrasound and UGI: 47/63 (75%) ultrasound first, 16/63 (25%) UGI first. Thirty-one per cent (31/101) had ultrasound only and 7/70 (10%) UGI only. The pathway diagnosed 7/8 (88%) infants with midgut malrotation with or without volvulus and one infant who had an inconclusive ultrasound examination with a suspected an internal hernia and who was found to have malrotation volvulus at surgery. Twenty-one infants who had confidently normal ultrasound examinations and who also had UGI all had a normal duodenojejunal flexure position. Ultrasound detected alternative pathology in eight children. Duodenal visualisation improved with time: 6/15 (40%) in the first 6 months to 23/34 (68%) after the first year. CONCLUSION: The transition to ultrasound as the first diagnostic test for midgut malrotation can be done safely and effectively in a UK centre, which previously relied solely on UGI.

Imaging characteristics of infantile fibrosarcoma.

AIM: To highlight the imaging findings in a case series of histologically confirmed infantile fibrosarcoma (IF) and identify any features specific to this entity. MATERIALS AND METHODS: Retrospective identification was undertaken of patients with histologically confirmed IF from the electronic patient databases of two institutions between 1 January 2010 and 1 May 2021. Available pre-treatment imaging, histopathological reports, and clinical records were reviewed. RESULTS: Eighteen patients with IF met the inclusion criteria. There were 10 male and eight female patients with a mean age at presentation of 3 weeks. All patients had the t (12; 15) chromosomal translocation. Eleven (61%) tumours were located in the extremities, three were in the craniofacial region, two were intrathoracic, one abdominal and one paraspinal. A single patient had extensive metastases. The tumours were generally isointense to skeletal muscle on T1-weighted sequences and hyperintense on T2 with heterogeneous enhancement and high cellularity seen as diffusion restriction. Fifteen of the 18 lesions were evaluated on ultrasound and appeared as heterogeneous, hypervascular solid or mixed solid/cystic masses, mimicking benign vascular lesions in two cases. CONCLUSION: The present two-centre, retrospective study of the largest case series described thus far demonstrates that IF is always highly cellular on magnetic resonance imaging but has no other specific imaging features. It should be considered in the differential diagnosis of any enlarging soft-tissue, solid mass arising in the limbs or neck at birth or in infancy.