Cara E. Morin

Summary: Allogeneic haematopoietic stem cell transplantation (HSCT) is curative for sickle cell disease (SCD) ‐ a group of inherited haemoglobin disorders encompassing homozygous haemoglobin S (HbSS) and compound heterozygous sickling disorders, including haemoglobin SC disease (HbSC), haemoglobin S/β ⁰ ‐thalassaemia (HbSβ ⁰ ), haemoglobin S/β ⁺ ‐thalassaemia (HbSβ ⁺ ), etc., but its long‐term impact on SCD myocardial remodelling is incompletely characterized. We performed serial cardiac magnetic resonance imaging (CMR) and echocardiography in children and young adults with SCD undergoing matched‐sibling or haploidentical HSCT in a prospective clinical trial with up to 36 months of post‐HSCT follow‐up. CMR assessments were conducted before HSCT and through the post‐HSCT period. Echocardiographic parameters at 12 months post HSCT were compared with those of age‐matched participants receiving disease‐modifying therapies (DMTs). Among 20 HSCT recipients (mean age 14.8 years), CMR demonstrated progressive reductions in biventricular volumes and left atrial volume over 36 months, with preservation of ejection fraction. Extra‐cellular volume, a surrogate marker of myocardial fibrosis, showed significant improvement from baseline, having normalized in nearly all participants assessed at 36 months. Compared with age‐matched DMT recipients, HSCT recipients had lower tricuspid regurgitant jet velocity and improved diastolic parameters at 12 months post‐HSCT, with normalization of cardiac output on echocardiography. These findings demonstrate sustained reversal of myocardial fibrosis and structural cardiac remodelling after HSCT for SCD. HSCT may, therefore, modify the trajectory of SCD cardiomyopathy beyond the improvements achieved with current DMTs.

Implementing a rapid MRI program requires buy-in and collaboration from all stakeholders and can lead to fast, accurate diagnosis of common and uncommon pediatric pathologic conditions in the emergent setting.

Background Balanced steady-state free-precession (bSSFP) cine imaging is the clinical standard for ventricular function assessment but requires multiple breath-holds, which can be challenging for pediatric and young adult patients. Deep learning (DL)–accelerated cine imaging offers the potential to reduce breath-hold burden, shorten scan time, and enable free-breathing acquisitions. Objective To clinically evaluate a commercially available DL-accelerated cine bSSFP sequence (SonicDL) across multiple acceleration levels and breath-hold/free-breathing configurations, and to assess diagnostic image quality, ventricular volumetric accuracy, and scan time reductions. Materials and methods This retrospective study included 25 patients with pectus excavatum and 15 with cardiomyopathy who underwent conventional cine imaging with breath-hold duration of nine cardiac-cycle interval (9-RR) and SonicDL acquisitions at 4-RR breath-hold, 1-RR breath-hold, and 1-RR free breathing. Diagnostic image quality was independently scored by three expert readers using a 5-point scale. Automated DL-based segmentation provided biventricular volumetric indices, with phase-contrast flow serving as the physiological reference for stroke volume. Statistical analysis included repeated-measures ANOVA, paired tests, ICCs, and Bland–Altman analysis. Results SonicDL significantly reduced scan time 57% (4-RR breath-hold), 79% (1-RR breath-hold), and 87% (1-RR free breathing) compared with 9-RR breath-hold imaging. Diagnostic image quality was highest for 4-RR breath-hold (median 4.50), significantly exceeding other protocols (P2 for most parameters) with limits of agreement typically within ±6 mL/m². Stroke volumes showed close agreement with phase-contrast flow (biases 1-5 mL/m²) across all protocols. In cardiomyopathy patients, diagnostic image quality was lower overall, but volumetric indices agreement remained within clinically acceptable ranges. Conclusion SonicDL cine bSSFP imaging substantially reduces breath-hold burden and scan time while maintaining diagnostic image quality and close agreement with conventional cine and physiologic flow measurements. The 4-RR breath-hold protocol provided the most favorable balance of acceleration and fidelity, while free-breathing acquisitions offered a practical alternative for patients with limited breath-hold capacity. Graphical abstract The alternative text for this image may have been generated using AI.

Deep learning–based hepatoblastoma segmentation models trained on pediatric CT and MRI scans demonstrated good agreement with human annotators and their consensus. Pediatric contrast-enhanced CT model outperformed the adult CT-trained model.

Asymptomatic infection poses a significant risk for children undergoing hematopoietic stem cell transplantation (HSCT). Pre‐transplant surveillance computed tomography (CT) is commonly used to identify occult infection, though its diagnostic yield remains uncertain. We retrospectively reviewed pre‐HSCT CT examinations from 635 first‐time allogeneic transplant recipients to assess the frequency of occult pulmonary and abdominal infection. Potentially infectious findings were reported in 22% (110/494) of chest CTs but were uncommon in abdomen/pelvis CTs (2%; 7/449). These findings suggest that chest‐only surveillance imaging may be more efficient and could reduce unnecessary radiation and contrast exposure in pediatric HSCT candidates.