The comparison of magnetic resonance and fluoroscopic imaging options in the preoperative assessment of boys with anorectal malformations and a colostomy.

BACKGROUND: In recent decades, magnetic resonance imaging (MRI) has gained prominence as a standard diagnostic method for preoperative assessment in patients with anorectal malformations and a colostomy, with the potential to replace the classic fluoroscopic distal pressure colostogram (FDPC). Three MRI techniques are available: MRI-distal pressure colostogram with gadolinium (MRI-DPCG) or saline (MRI-DPCS) instillation into the colostomy and native MRI without colostomy instillation. OBJECTIVE: To evaluate and compare the diagnostic accuracy of MRI (native MRI, MRI-DPCG and MRI-DPCS) in the preoperative workup of boys with an anorectal malformation and a colostomy and to compare it to FDPC. MATERIALS AND METHODS: Sixty-two boys with preoperative MRI using one of the three approaches and 43 with FDPC met the inclusion criteria for this retrospective study. The presence and localization of rectal fistulas according to the Krickenbeck classification were evaluated and compared with intraoperative findings. RESULTS: The accuracy of fistula detection for MRI in general (regardless of the technique), MRI-DPCS, MRI-DPCG, native MRI and FDPC was 95% (59/62, P<0.001), 100% (12/12, P=0.03), 100% (30/30, P<0.001), 85% (17/20, P=0.41) and 72% (31/43, P=0.82), respectively. The accuracy of describing fistula type in patients with a correctly detected fistula using these methods was 96% (45/47, P<0.001), 100% (9/9, P<0.001), 100% (23/23, P<0.001), 87% (13/15, P<0.001) and 67% (13/21, P=0.002), respectively. CONCLUSION: MRI is a reliable method for detecting and classifying fistulas in boys with an anorectal malformation and a colostomy and can be considered the modality of first choice for preoperative workup.

Occult fractures detected on radiographs in young children with a concern for abusive head trauma.

AIMS: To determine the incidence of children < 2 years old with suspected abusive head trauma, to evaluate usage of dedicated skeletal radiographs and the incidence of clinically occult fractures on dedicated skeletal radiographs. METHODS: This is a retrospective single centre study of children < 2 years old with traumatic brain injury, referred to the University Hospital's Social Services Department between December 31, 2012 and December 31, 2020. Clinical and demographic data was retrieved from medical notes and imaging was reviewed by paediatric radiologists. RESULTS: 26 children (17 males), 2 weeks to 21 months of age (median age 3 months) were included. Eleven children (42%) had traumatic history, fourteen children (54%) had one or more bruises, eighteen children (69%) had abnormal neurological findings. 16 children (62%) had dedicated skeletal radiographs, 7 children (27%) had radiographs of part of the skeleton and 3 children (11%) had no skeletal radiographs. 5 out of 16 children (31%) with dedicated skeletal radiographs had a clinically occult fracture. 15 (83%) of clinically occult fractures had high specificity for abuse. CONCLUSION: The incidence of suspected abusive head trauma in children < 2 years old is low. Clinically occult fractures were detected in one third of children with dedicated skeletal radiographs. The majority of these fractures have high specificity for abuse. Dedicated skeletal imaging is not performed in more than one third of the children and hence fractures may be missed. Efforts should be taken to increase awareness of child abuse imaging protocols.

Integrated genomic analysis reveals actionable targets in pediatric spinal cord low-grade gliomas.

Gliomas are the most common central nervous tumors in children and adolescents. However, spinal cord low-grade gliomas (sLGGs) are rare, with scarce information on tumor genomics and epigenomics. To define the molecular landscape of sLGGs, we integrated clinical data, histology, and multi-level genetic and epigenetic analyses on a consecutive cohort of 26 pediatric patients. Driver molecular alteration was found in 92% of patients (24/26). A novel variant of KIAA1549:BRAF fusion (ex10:ex9) was identified using RNA-seq in four cases. Importantly, only one-third of oncogenic drivers could be revealed using standard diagnostic methods, and two-thirds of pediatric patients with sLGGs required extensive molecular examination. The majority (23/24) of detected alterations were potentially druggable targets. Four patients in our cohort received targeted therapy with MEK or NTRK inhibitors. Three of those exhibited clinical improvement (two with trametinib, one with larotrectinib), and two patients achieved partial response. Methylation profiling was implemented to further refine the diagnosis and revealed intertumoral heterogeneity in sLGGs. Although 55% of tumors clustered with pilocytic astrocytoma, other rare entities were identified in this patient population. In particular, diffuse leptomeningeal glioneuronal tumors (n = 3) and high-grade astrocytoma with piloid features (n = 1) and pleomorphic xanthoastrocytoma (n = 1) were present. A proportion of tumors (14%) had no match with the current version of the classifier. Complex molecular genetic sLGGs characterization was invaluable to refine diagnosis, which has proven to be essential in such a rare tumor entity. Moreover, identifying a high proportion of drugable targets in sLGGs opened an opportunity for new treatment modalities.