Pediatric Radiology最新文献

Chronic nonbacterial osteitis (CNO), including its multifocal form, chronic recurrent multifocal osteomyelitis (CRMO), is an autoinflammatory sterile bone disorder with protean imaging features across the appendicular and axial skeletons in children and adolescents. Magnetic resonance imaging (MRI)-particularly whole-body MRI (WBMRI)-is pivotal for diagnostic imaging, mapping total inflammatory burden, demonstrating multifocality, and monitoring treatment response. Radiographs are frequently normal early in the disease. Beyond the classic metaphyseal pattern, we demonstrate atypical presentations that often mimic other conditions, such as infection or malignancy: progressive collapsing vertebral disease with vertebra plana, hip arthritis due to involvement of intra-articular metaphyseal equivalents, myositis not related to areas of active osteitis, extensive periosteal new bone in long bones, pseudotumoral lesions of flat bones, and craniofacial involvement. This pictorial review provides a structured diagnostic approach to prompt consideration of CNO, facilitate differentiation from bacterial osteomyelitis and bone tumors in the differential diagnosis, and support early, targeted anti-inflammatory therapy.

Background: Photon-counting CT (PCCT) has the potential to improve diagnosis and reduce radiation exposure in pediatric congenital heart disease. Early data in pediatric patients has shown advantages of advanced post-processing techniques that are currently only available with high kilovolt (kV) protocols.

Objective: The purpose of our study was to compare image quality and radiation dose for low kV (70) and high kV (120) protocols in patients weighing under 10 kg.

Methods: In this IRB-approved retrospective review of ultra-high pitch cardiac CT scans in patients under 10 kg, we evaluated two protocols on a PCCT scanner: low kV (70) and high kV (120). Patient demographics, contrast-to-noise ratio in aorta and pulmonary artery, and subjective image quality scores using a 5-point Likert scale were evaluated by two readers in addition to radiation dose comparison.

Results: Fifty-eight scans were included, 28 in the 70 kV cohort and 30 in the 120 kV cohort. Median age was 0.17 years for 70 kV and 0.33 years for 120 kV and weight was 4.5 kg for 70 kV and 5.4 kg for 120 kV. Contrast-to-noise ratios (aorta 14.8 vs 17.8, P=0.6) and Likert scores for aorta (median 5 for both groups, P=0.2) were similar for both protocols. Radiation dose was significantly lower in the 70 kV group with CTDI of 0.13 mGy vs 0.25 mGy for 120 kV (P<0.001).

Conclusion: A 70 kV protocol shows promise for reducing radiation dose in infants with similar image quality compared to the 120 kV protocol, although advanced spectral reconstructions would not be available.

Background: Federal regulations require an audible alarm for each passage of 5 min of cumulative x-ray irradiation time during a diagnostic fluoroscopy procedure. In contrast to United States federal requirements, regulations vary amongst individual states.

Objective: Determine whether a shortened fluoroscopy time alarm reduces pediatric patient ionizing radiation exposure for modified barium swallow studies (MBSS).

Materials and methods: Fluoroscopy time alarms were changed from the passage of every 5 min to 2 min. A retrospective analysis of MBSS compared patient reference point air kerma and fluoroscopy time before and after the alarm time was shortened.

Results: A total of 3,875 MBSS performed on patients under the age of 18 years were analyzed. Reductions of 14.9% and 19.6% for average and median reference point air kerma (P<0.001) and 15.5% and 16.2% for average and median fluoroscopy time (P<0.001) were observed at the main campus for MBSS performed before and after changing the fluoroscopy time alarm from 5 min to 2 min. Reductions of 14.3% and 9.1% for average and median reference point air kerma (P<0.001) and 13.9% and 8.3% for average and median fluoroscopy time (P<0.001) were observed at the satellite locations for MBSS performed before and after changing the fluoroscopy time alarm.

Conclusion: This retrospective study suggests a shortened fluoroscopy time alarm can significantly lower pediatric patient dose and fluoroscopy time in MBSS. State and federal regulations should consider establishing flexible fluoroscopic alarm settings, especially when used for the pediatric population.

Background: Accurate Cobb angle measurement is essential in adolescent idiopathic scoliosis (AIS), but evidence on artificial intelligence (AI) performance in pediatric patients, especially with severe curves, is limited.

Objective: This study evaluated the accuracy of a commercially available deep learning software in measuring Cobb angles in surgical cases of AIS and compared its performance with that of radiology residents.

Methods: A total of 151 preoperative anteroposterior whole spine X-rays were analyzed. The ground truth was established by consensus between a pediatric radiologist and a pediatric orthopedic surgeon. The mean absolute error (MAE) of the AI and six radiology residents was calculated. Wilcoxon signed-rank test and intraclass correlation coefficients (ICC) were computed.

Results: The dataset included 151 angles categorized as moderate (13; 20-39°), severe (74; 40-59°), and extreme (64; ≥60°). Overall, the AI's MAE was 4.57° [95%CI 3.85°, 5.29°], significantly higher than that of the residents' (P=0.0017). Scoliosis severity significantly affected MAE in both groups. For extreme scoliosis, the MAE of the AI (6.53° [95%CI 5.06°, 7.86°]) was significantly higher than that of the residents (3.61° [95%CI, 3.17°, 3.97°]) (P<0.001). No significant difference in MAE was observed between patients with moderate and severe scoliosis (P=0.86). The agreement between the ICC between the AI and the ground truth was 0.89 [95%CI 0.69, 0.95].

Conclusion: The Cobb angle measurements obtained with this software agree with those of experts for moderate and severe scoliosis with a clinically acceptable average error, without significant difference compared to radiology residents. AI accuracy significantly decreases in patients with extreme scoliosis, highlighting the need for radiologist oversight.

Background: The migration index (MI) is a quantitative measurement of femoral head extrusion used to help risk stratify neuromuscular hip dysplasia. However, MI relies upon the radiographically visible ossified capital femoral epiphysis which is only partially ossified in young children and therefore may potentially underestimate hip extrusion.

Objective: To compare proof-of-concept accuracy of using a metaphyseal and traditional MI to measure femoral head extrusion in children compared with an MRI-based anatomic reference standard.

Materials and methods: We reviewed 205 normal hips, each by MRI and x-ray, in patients aged 6 months - 6 years old. Three femoral head MI measurements were performed: (1) MRI-MI: percentage of the cartilaginous femoral head uncovered by the osseous acetabulum (anatomic reference standard); (2) traditional MI (TMI) x-ray: percentage of osseous capital femoral head uncovered by the osseous acetabulum; (3) metaphyseal MI x-ray (MeMI): percentage of the femoral head uncovered by the osseous acetabulum, using the metaphyseal vertex used as a surrogate for lateral margin of the cartilaginous femoral head. Statistical analysis of the three measurement techniques was performed using paired t-tests. Intraclass correlation coefficient was calculated.

Results: There was a statistically significant underestimation of femoral head extrusion using TMI and MeMI (P<0.05) when compared with MRI-MI, but MeMI more closely approximated the MRI-MI. Inter-reader reliability showed excellent agreement.

Conclusion: The MeMI better approximates the MRI anatomic landmarks for measuring the true degree of femoral head extrusion in children 6 months - 5 years of age. Its usage should be considered in lieu of the TMI in children under 5 years of age for radiographically determining MI.

Background: Diffusion magnetic resonance imaging has emerged as an opportunity to explore brain white matter fiber tracts (WMFTs) through 3D digital reconstruction. This method could be useful in investigating the relationship between positional plagiocephaly and developmental problems; however, this has not been fully explored.

Objective: Evaluate WMFTs of healthy infants in two age groups with a range of positional plagiocephaly from normal to severe.

Materials and methods: This exploratory study, conducted at a free-standing, quaternary pediatric hospital in the Northeastern United States, utilized an existing database of healthy infants' MRIs obtained between 1 month and 4 months of age. MRIs were included if deemed good quality and had complete T1- and diffusion-weighted sequences and excluded if there were measurement disagreements or MRI data processing problems. Positional plagiocephaly severity was calculated using the Cranial Vault Asymmetry Index (CVAI). A repeated-measures regression model was constructed to assess the association of positional plagiocephaly severity with WMFTs fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD).

Results: Median age of 18 infants was 64.5 (IQR 71) days at the time of MRI. FA had a negative association with CVAI overall (β±SE=-0.53±0.51% per unit CVAI, P=0.32) and in both age groups. MD and RD had a positive association with CVAI overall (β±SE=1.31±0.46% per unit CVAI, P=0.013; β±SE=1.54±0.54% per unit CVAI, P=0.012) and in both age groups and all pathways.

Conclusion: As the severity of positional plagiocephaly increases, differences in WMFT formation are observed, suggesting the need for longitudinal studies with cognitive and behavioral assessments.

Identifying the artery of Adamkiewicz (AoA) is essential for minimizing the risk of spinal cord ischemia that can result from injury or displacement during aortopexy. A pre-operative CT angiogram (CTA) is commonly requested; however, locating the artery can be challenging due to its small size and variable course. To enhance the visualization of the artery of Adamkiewicz, it is effective to increase the tube current while maintaining a low kV of 70 and raising the Hounsfield unit (HU) trigger threshold. This method adheres to the As Low As Reasonably Achievable (ALARA) principle, ensuring a reliably diagnostic study.