Pediatric Radiology最新文献

Advancements in understanding the clinical, biochemical, and genetic aspects of primary mitochondrial disorders, along with the identification of a broad range of phenotypes frequently involving the central nervous system, have opened a new and crucial area in neuroimaging. This expanding knowledge presents significant challenges for radiologists in clinical settings, as the neuroimaging features and their associated metabolic abnormalities become more complex. This review offers a comprehensive overview of the key neuroimaging features associated with the common primary mitochondrial disorders. It highlights both the classical imaging findings and the emerging diagnostic insights related to several previously identified causative genes for these diseases. The review also provides an in-depth description of the clinicoradiologic presentations and potential underlying mitochondrial defects, aiming to enhance diagnostic abilities of radiologists in identifying primary mitochondrial diseases in their clinical practice.

The World Federation of Pediatric Imaging (WFPI) MR Protocols Committee was formed in response to the critical need for standardized magnetic resonance imaging (MRI) protocols tailored specifically for pediatric populations. This initiative addresses the inherent challenges and variabilities in pediatric MRI practices due to the unique physiological and anatomical characteristics of children, which often result in extended scan times, increased costs, and greater need for sedation. The committee, comprising a diverse group of international radiologists, pediatric imaging societies, and major MRI vendors, collaboratively developed a comprehensive set of MRI protocols. These protocols are designed to enhance diagnostic accuracy, reduce sedation use, and streamline workflows, thereby minimizing healthcare disparities across global regions. Protocols cover a wide range of applications, including neuroradiology, abdominal imaging, and musculoskeletal conditions, with specific focus on practical implementation in both high-resource and resource-limited settings. After rigorous development and refinement through global feedback, these protocols have been made accessible through the WFPI website and will be directly integrated into MRI systems via vendor collaborations. These protocols provide a flexible, foundational approach that can be adapted to suit the needs of centers worldwide. This ensures that even basic protocols are accessible across different settings, allowing customization based on available resources and specific clinical demands.

Background: Ultrasound (US) is increasingly used as the first-line imaging modality for the diagnosis of midgut volvulus, but may be non-diagnostic in some cases.

Objective: To determine the frequency and factors associated with non-diagnostic US for each midgut volvulus and malrotation in a multi-institutional sample.

Materials and methods: We conducted a retrospective multi-institutional study of children (age 0-18 years) who underwent US to evaluate for midgut volvulus and malrotation between January 1, 2018, and June 30, 2021, and had an available reference standard of one of the following: upper GI series, CT/MRI, surgery, or, for volvulus, clinical follow-up at 30 days or greater. Blinded review of US images was performed by a single radiologist at each institution. When available, radiographs acquired ≤3 h from the US were reviewed for bowel gas pattern. After blinded review, original ultrasound reports were classified as diagnostic or non-diagnostic for midgut volvulus and malrotation. Stepwise logistic regression identified the most important predictors of non-diagnostic US.

Results: In total, 637 patients were imaged for midgut volvulus and 311 for malrotation. Based on original report review, non-diagnostic proportions of examinations for volvulus and malrotation were 13.5% (86/637) and 25.7% (80/311), respectively. Based on blinded review, non-diagnostic proportions of examinations for volvulus and malrotation were 17.3% (110/637) and 37.6% (117/311), respectively. Of the patients with US considered non-diagnostic for volvulus by original reports, 2.3% (2/86) were subsequently found to have volvulus. Among patients with non-diagnostic US for volvulus by blinded review (n=110), none was found to have volvulus. Gaseous dilation with elongation of bowel on radiography was the single best predictor of a non-diagnostic US in blinded interpretation for volvulus and malrotation (OR=8.2 and 9.2; 95%CI 3.7-19.8 and 1.7-89.4, respectively) and in original radiology reports for volvulus (OR=4.5; 95%CI 2.2-9.5).

Conclusion: A small fraction of a multi-institutional sample of US for midgut volvulus was non-diagnostic; however, assessment of malrotation without volvulus is associated with a higher frequency of non-diagnostic examinations. Dilated bowel gas pattern on radiography is the strongest predictor for a non-diagnostic US, although it does not necessarily preclude a diagnostic exam.

Background: Magnetic resonance cholangiopancreatography (MRCP) is used to diagnose and monitor primary sclerosing cholangitis (PSC).

Objective: To assess inter-reader agreement for the diagnosis of PSC/autoimmune sclerosing cholangitis (ASC) and for individual MRCP features of cholangiopathy in a pediatric sample.

Materials and methods: This was a retrospective, IRB-approved study that included MRCP examinations from patients <21 years old with known or suspected cholangiopathy. Multiple biliary and hepatic imaging features were assessed independently by nine pediatric radiologists using 2D and 3D MRCP images. Kappa (κ) statistics and intra-class correlation coefficients (ICC) with 95% confidence intervals (CI) were used to measure inter-reader agreement.

Results: Seventy-five patients were included (median age=16.8 [IQR 13.8-18.7] years; 48 boys); 22.7% (17/75) had PSC, 22.7% (17/75) had ASC, and 54.7% (41/75) had other diagnoses. Among observers, agreement was only slight for presence of cholangiopathy (κ=0.15 [95% CI 0.07 to 0.23]) and presence of PSC/ASC (κ=0.13 [0.06 to 0.21]). Agreement was poor for categorical intrahepatic stricture number (κ=-0.002 [(-0.16 to 0.15]) and stricture extent (κ=-0.06 [-0.09 to-0.02]). Agreement was slight for presence of intrahepatic stricturing disease (κ=0.08 [0.04 to 0.12]). Most other findings had fair agreement between readers (including intrahepatic focal dilations, intrahepatic and extrahepatic diverticula, diffuse extrahepatic dilation without stricture, bile duct mural thickening, and biliary obstruction [κ=0.22 to 0.34]). There was moderate agreement for categorical extrahepatic stricture length (κ=0.46 [-0.11 to 1]) and presence of extrahepatic biliary dilation (κ=0.53 [0.40 to 0.65]). There was excellent agreement for extrahepatic bile duct maximum diameter (ICC=0.89 [0.85 to 0.92]).

Conclusion: Inter-reader agreement for interpreting MRCP in children and young adults is slight to fair for the diagnosis of PSC/ASC and for most findings of cholangiopathy.

Objective: We determined the reliability of a three-dimensional (3D) ultrasound (US) segmentation software for evaluating volumetric hydronephrosis index (HI) and renal parenchymal and pelvicalyceal volume in children with urinary tract dilation (UTD).

Material and methods: From 1/2019 to 9/2023, children clinically scheduled for a renal imaging exam to assess UTD at a single center were prospectively enrolled. They underwent a dedicated two-dimensional (2D) and 3D US renal exam. A UTD score was assigned per kidney from the 2D images based on the 2014 consensus classification by an experienced pediatric radiologist. From the 3D dataset, the renal parenchyma and collecting system were independently segmented by three trained raters using a semi-automated software. From this segmentation, the kidney parenchymal and pelvicalyceal volume, dimensions, and volumetric HI values were analyzed using the intraclass correlation coefficient to grade inter-rater reliability.

Results: Forty-eight studies from 47 patients were included (65% male; median age 24 months; IQR 61 months). From these, 46 right and 40 left kidneys were chosen based on image quality. Twenty-nine (33.7%) kidneys had no UTD, 10 (11.6%) had UTD P1, 23 (26.7%) had UTD P2, and 24 (27.9%) had UTD P3. Inter-rater reliability was almost perfect across all parameters, with estimates ranging from 0.85 to 0.95. In sub-analysis of kidneys with UTD P2 and UTD P3, volumetric HI had the lowest inter-rater agreement (0.75 and 0.66, respectively).

Conclusions: Semi-automated 3D US segmentation for kidneys with UTD can reliably assess renal dimensions, parenchymal and collecting system volumes, and volumetric HI among raters.