Pediatric Radiology Research Articles

3D ultrasound volume quantification for pediatric urinary tract dilation: a semi-automated segmentation software inter-rater analysis.

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

State of original pediatric radiology research in major radiology journals other than Pediatric Radiology.

Understanding distribution of published pediatric imaging research in radiology journals is relevant to understanding the state of research in the field. To understand the current state of published original pediatric imaging research in major clinical radiology journals other than Pediatric Radiology. We reviewed clinical imaging journals from among the top 20 radiology journals according to the Google Scholar h5-index as of June 2024. Content pages were reviewed for the years 2019-2023 to identify pediatric original research. Study titles were reviewed to subclassify by pediatric subspecialty. The number of citations for each pediatric article and for all articles in the journal was documented, and a citation to article ratio was calculated. The Wilcoxon signed-rank test was used to assess differences in citation to article ratio. Nine journals and 636 pediatric articles were included. The fraction of pediatric studies in each journal ranged from 0.9% (12/1,310) to 15.3% (244/1,594) (median 2.2% [88/3,983]). Pediatric neuroimaging studies were the most common (46.4% [295/636] of all pediatric studies, 23.2% [91/392] of pediatric studies in journals other than American Journal of Neuroradiology). The citation to article ratio for pediatric articles ranged from 3.3 to 25.2 across journals. Overall, the citation to article ratio for pediatric studies was not significantly different from non-pediatric studies (P=0.12). Pediatric research makes up a small fraction of original research in major clinical radiology journals, with neuroimaging reflecting the bulk of published work. The average number of citations per pediatric article is similar to that of non-pediatric articles.

Bronchiectasis in African children: Prevalence, etiology, and clinical spectrum at a pediatric tertiary hospital in Cape Town, South Africa

Objectives: The objective of the study was to describe the disease burden, etiology, and clinical spectrum of bronchiectasis in children attending a tertiary hospital in Cape Town, South Africa. Materials and Methods: Data were collected by chart review of all patients aged 3 months to 15 years attending the respiratory clinic at Red Cross War Memorial Children’s Hospital between January 2019 and December 2019. We included children who had a diagnosis of bronchiectasis based on a history of a recurrent (>3 episodes/year) or persistent (>4 weeks) wet or productive cough and a clinical phenotype characterized by any of the following: Exertion dyspnea, recurrent chest infections, growth failure, finger clubbing, and chest deformity associated with radiographic features of bronchiectasis on chest radiograph or chest tomography reported by a pediatric radiologist. Patients with cystic fibrosis were excluded from the study. Results: Of 337 children seen at the respiratory clinic during the study period, 58 (17.2%) had bronchiectasis that was diagnosed at a mean age of 34 months (standard deviation 26), and 32 (55.0%) were female. The most common causes of bronchiectasis were post-infectious 25 (43.1%), and underlying immunodeficiencies 19 (32.8%), including 16/58 (27.6%) who were living with human immunodeficiency virus (HIV) and 3 (5.1%) with primary immunodeficiency. Other causes included aspiration syndrome 8 (13.8%) and anatomical abnormalities 4 (6.9%). Of the participants with post-infectious bronchiectasis, tuberculosis (TB) was the most common organism isolated 16 (64.0%), and most common in children living with HIV (11/16, 68.8%). Cough was common in 48 (82.8%), with wet cough being predominant in 41 (85.4%), course crepitations were found in 37 (63.8%), hyperinflation in 24 (41.4%), finger clubbing in 21 (36.2%), wheeze in 16 (29.3%), and exertional dyspnea in 7 (12.0%). Conclusion: Bronchiectasis is common in South African children, usually resulting from previous pneumonia episodes, with TB being the most common infective cause. The importance of early diagnosis and treatment of underlying causes, especially infectious diseases in low-middle-income settings, to prevent bronchiectasis is highlighted.

Artificial intelligence (AI) for paediatric fracture detection: a multireader multicase (MRMC) study protocol

IntroductionPaediatric fractures are common but can be easily missed on radiography leading to potentially serious implications including long-term pain, disability and missed opportunities for safeguarding in cases of inflicted injury....

Radiology resident proficiency in pediatric trauma cases: a comparative analysis based on trauma center status using the WIDI SIM exam.

To investigate the correlation between pediatric and adult trauma center status and radiology resident performance on pediatric trauma cases using the WIDI SIM exam. The WIDI SIM is a validated computer-aided simulation that assesses radiology residents' preparedness for independent call duty. It includes 65 cases across various imaging modalities derived from actual patient encounters. Faculty score free-text responses using a standardized 0-10 scale rubric. We analyzed 8,488 WIDI SIM exam scores from 35 pediatric trauma cases across 52 programs. A negative binomial regression model adjusting for resident level, imaging modality, and case specialty was employed to evaluate the impact of pediatric and adult trauma center status on resident performance. Both pediatric trauma center status (p = 0.0005) and adult trauma center status (p = 0.0003) were significant predictors of higher resident scores. Resident level was also significant, with higher-level residents performing better than first-year residents (p < 0.001). Residents performed worse on MR and US modalities compared to CT, and performance varied by case specialty. Radiology residents' pediatric trauma imaging skills are significantly linked to pediatric and adult trauma center status. Given most pediatric traumas occur outside pediatric trauma centers, targeted training strategies should be considered to ensure residents develop essential diagnostic skills.

The effect of urinary diversion on kidney function in posterior urethral valves and ureterovesical obstruction.

Posterior urethral valves (PUV) and ureterovesical junction obstruction (UVJO) are common etiologies of lower urinary tract obstruction. The primary objective of therapy is to alleviate the obstruction in the urinary system. Temporary urinary diversion may be necessary in certain situations, such as Urinary tract infection (UTI), sepsis, and unchanging hydronephrosis. This study, aims to assess kidney parameters after urinary diversion (either pyelostomy or ureterostomy) in patients with PUV and UVJO. We conducted a retrospective analysis of all patients diagnosed with PUV or UVJO and treated with urinary diversion following urinary undiversion at our facility between 2015 and 2020. The following variables were collected: demographic details, surgical interventions (type of diversion), serum creatinine throughout follow-up, anterior-posterior diameter of the pelvis (APP), anterior-posterior diameter of the ureter (APU), and sonographic findings of renal parenchymal thickness (PT) as documented by a pediatric radiologist. Additionally, before and after urinary diversion, a Dimercapto succinic acid (DMSA) nuclear renal scan was conducted to assess renal function. We analyzed 67 patients, with a mean follow-up of 38.3months, undergoing either ureterostomy (42 patients) or pyelostomy (25 patients). This included 38 patients with PUV and 29 with UVJO. In PUV patients, significant improvements were observed in APP (MD = 5.56 ± 11.6, p = 0.0194), APU (MD = 5.57 ± 7.28, p < 0.001), and PT (MD = 3.66 ± 2.75, p < 0.001). Similarly, UVJO patients experienced significant improvements in APP (MD = 12.18 ± 18.63, p = 0.005), APU (MD = 7.82 ± 8.98, p = 0.001), and PT (MD = 2.79 ± 3.33, p = 0.001). DMSA scores did not significantly change in either group (p > 0.05). Notably, APP improved more in UVJO patients compared to PUV patients (p = 0.047). Our study suggests that urinary diversion could improve APP, APU, and renal parenchymal thickness in PUV and UVJO patients. The improvement of APP in UVJO patients was greater than in the PUV group. We propose further multi-center studies with longer durations of follow-up and more detailed additional data to support and confirm our results.

Unusual Signal of Lymphadenopathy in Children with Nodular Sclerosing Hodgkin Lymphoma.

The current guidelines for initial cross-sectional imaging in pediatric lymphomas involve computed tomography (CT) of the chest, abdomen, and pelvis. However, whole-body magnetic resonance imaging (MRI) can be favored over CT for diagnosing and staging the disease, given its lack of ionizing radiation and its higher tissue contrast. Imaging characteristics of lymphoid tissue on MRI include a high T2/short tau inversion recovery (STIR) signal. A low or intermediate signal of lymphadenopathy on T2 and STIR images is an unexpected finding, noted anecdotally in nodular sclerosing Hodgkin lymphoma. This signal may be characteristic of a histological subtype of the disease and, if confirmed, could potentially be used to avoid biopsy. In this study, we aimed to review signal characteristics of lymphadenopathy in patients with biopsy-confirmed nodular sclerosing Hodgkin lymphoma. We undertook a retrospective review of relevant MR studies of patients with nodular sclerosing Hodgkin lymphoma. Studies were reviewed by an experienced pediatric radiologist regarding lymph node signal, especially on T2/STIR. Eleven children with nodular sclerosing Hodgkin lymphoma were included. Median age at the time of MRI was 14.3 (IQR: 13.9-16.1) years, and nine were boys. Five patients showed some lymphadenopathy with a low T2/STIR signal, and six showed an intermediate T2/STIR signal. Central gadolinium non-enhancement was observed in four patients. All eleven patients (100%) with a diagnosis of nodular sclerosing Hodgkin lymphoma showed some lymphadenopathy with a low or intermediate T2/STIR signal, and five children (45.5%) showed a frank low signal of some lymphadenopathy, a feature which may prove to be a biomarker for this histology.

Dual-energy computed tomography: pediatric considerations.

Multidetector computed tomography (CT) has revolutionized medicine and is now a fundamental aspect of modern radiology. Hardware and software advancements have significantly improved CT accessibility, image quality, and acquisition times. While considerable attention has been directed towards the potential risks of ionizing radiation from CT scans in children, recent concerns regarding the possible short- and long-term risks related to magnetic resonance imaging (MRI) conducted under general anesthesia have generated fresh interest in novel pediatric CT applications and techniques that allow imaging of awake patients at low radiation doses. Among these novel techniques, dual-energy CT (DECT) stands out for its ability to provide enhanced diagnostic information, reduce radiation doses further, and facilitate faster scans, making it a highly promising tool in pediatric radiology. This manuscript explores the current role of DECT in pediatric imaging, emphasizing its technical foundations, hardware configurations, and various reconstruction techniques. We discuss advanced post-processing techniques, such as material decomposition algorithms and virtual monoenergetic imaging, highlighting their clinical advantages in improving diagnostic accuracy and patient outcomes. Furthermore, the paper reviews the clinical applications of DECT in evaluating pulmonary perfusion, cardiovascular assessments, and oncologic imaging in pediatric patients.

Update on surveillance guidelines in emerging Wilms tumor predisposition syndromes.

Wilms tumors are commonly associated with predisposition syndromes. Many of these syndromes are associated with specific phenotypic features and are discussed in the related paper from the AACR Pediatric Cancer Working Group. Guidelines for surveillance in this population were published in 2017 but since then several studies have identified new genes with recurrent pathogenic variants associated with increased risk for Wilms tumor development. In general, variants in these genes are less likely to be associated with other phenotypic features. Recently, members of the AACR Pediatric Cancer Working Group met to update surveillance guidelines for patients with a predisposition to Wilms tumors with a review of recently published evidence and risk estimates. Risk estimates for Wilms tumor for the more recently described genes are discussed here along with suggested surveillance guidelines for these populations. Several other emerging clinical scenarios associated with Wilms tumor predisposition are also discussed including patients with family histories of Wilms tumor and no identified causative gene, patients with bilateral tumors, and patients with somatic mosaicism for chromosome 11p15.5 alterations. This perspective serves to update pediatric oncologists, geneticists, radiologists, counselors and other healthcare professionals on emerging evidence and harmonize updated surveillance recommendations in the North American and Australian context for patients with emerging forms of Wilms tumor predisposition.

Pediatric contrast-enhanced chest CT on a photon-counting detector CT: radiation dose and image quality compared to energy-integrated detector CT.

Photon counting detector (PCD) CT benefits from reduced noise compared with conventional energy-integrating detector (EID) CT, which should translate to improved image quality and reduced radiation exposure for pediatric patients undergoing chest CT with IV contrast. To determine the differences in radiation exposure and image quality of PCD CT and EID CT in pediatric chest CT with intravenous (IV) contrast. In this institutional review board-approved retrospective observational study, 20 scan pairs (20 PCD CT; 20 EID CT) for children who underwent chest CT with IV contrast on both a PCD CT (Siemens NAEOTOM Alpha) and an EID CT (Siemens SOMATOM Definition Edge or Force) within 12months were reviewed independently by three pediatric radiologists for three subjective quality features on 5-point Likert scales: overall quality, small structure delineation, and motion artifact. Objective measures of image quality (image noise, signal-to-noise ratio, and contrast-to-noise ratio) were assessed by a single radiologist in several locations in the chest through region of interest measurement of Hounsfield units (HU) and standard deviation. Patient-related and radiation exposure parameters were collected for each scan and summarized with median and interquartile range (IQR). The Wilcoxon rank-sum test was utilized to compare groups. A P < 0.05 indicated statistical significance. Inter-observer agreement of subjective image quality metrics was analyzed using weighted kappa. Age (14.2years vs 13.8years, P= 0.15), height (P= 0.13), weight (P= 0.21), and BMI (P = 0.24) did not significantly differ between groups. There were 10 male and 3 female patients. Compared to EID CT, PCD CT showed lower radiation exposure parameters including volumetric CT dose index, 1.7mGy (IQR 1.1-2.4mGy) vs 3.8mGy (IQR 2.0-4.7mGy) (P< 0.01), and size-specific dose estimate, 2.6mGy (IQR 1.8-3.1mGy) vs 5.0mGy (IQR 3.3-6.2mGy) (P< 0.01). Objective image quality of lung parenchyma was improved on the PCD CT scanner, including image noise 119.5 HU (IQR 95.4-135.7 HU) vs 143.1 HU (IQR 125.4-169.8 HU) (P < 0.01), signal-to-noise ratio (SNR) -6.1 (IQR -8.4 to -4.8) vs -4.9 (IQR -5.6 to -3.8) (P= 0.01), and contrast-to-noise ratio -63.9 (-84.1 to -57.5) vs -60.5 (-76.3 to -52.5) (P = 0.01). Motion artifact was improved on the PCD CT scanner (P< 0.01). No significant differences in overall image quality or small structure delineation were identified (P= 0.06 and P= 0.31). PCD CT pediatric chest CT had significantly reduced radiation exposure, improved image quality, and reduced motion artifact compared with EID CT.

12 Access to paediatric maltreatment services through a northern community hospital

Abstract Background Few studies have evaluated how paediatric maltreatment services based in community hospitals can provide access to care for populations who live far away from tertiary centres. The Violence Intervention Prevention Program (VIPP) and the Paediatric Abuse and Referral Evaluation (PARE) clinic based in a northern community hospital in Canada offer assessment for sexual and physical maltreatment. Objectives The aim of the study was to describe demographic and clinical characteristics of patients accessing VIPP and PARE services and to characterize the length of time required to access care. Design/Methods We conducted a retrospective chart review of patients, under 16 years of age, who attended PARE clinic for initial consultation between 2017-2019. Analyses were descriptive. This work was approved by the research ethics board at our hospital. There are no funding disclosures. Results Of 164 patients, 62.2% were female; 37.8% male. The mean age was 6.6 years, ranging from 1 month to 15.9 years. 54.3% of referrals were for suspected physical maltreatment, 44.4% for suspected sexual maltreatment and 1.2% for both. 87.5% of patients listed home addresses within the hospital’s city limits. The maximum distance travelled from home to access care was 171 km. 87.2% of patients presented through the emergency department; a minority presented through direct referral to outpatient services (11.5%) or through inpatient (1.2%). When called from the emergency department, on-call VIPP nurses responded within a mean of 32 minutes for initial assessment. These patients received a maltreatment assessment by a paediatrician through the PARE clinic a mean of 14.3 days later. If patients did not present through the emergency department, the mean wait time for a maltreatment assessment by a paediatrician was 16 days. 13.4% (22/164) required referral to other medical or multidisciplinary services. General paediatrics (11/22) was the most frequent referral, followed by community speech programs (5/22). A minority (3.0%) of cases required consultation with external maltreatment teams, where two cases were peer-reviewed with a tertiary care team, one with a paediatric maltreatment physician at another community hospital and two cases were reviewed with a paediatric tertiary care radiologist. Conclusion Our results suggest that community-based paediatric maltreatment services provide care for our regional northern population. There is timely on-call access to allied-health providers through the emergency department. All patients were able to be assessed locally and none were required to travel to a tertiary care hospital. Further study is needed to assess how our data compares to other community maltreatment programs.

Tumor ablation in children.

Tumor ablation represents an increasingly important topic in pediatric interventional radiology. Many ablative techniques are well known and established in the adult population, and the adoption of these techniques in the pediatric field is increasing. Image-guided tumor ablation represents a wide category of interventional radiology procedures that can be applied to both benign and malignant pediatric solid tumors. Tumor ablation, either alone or in combination with locoregional therapy, can have curative, debulking, or palliative effects on a wide variety of histological tumor types.

Comparison of low-dose CT and MRI in enthesitis-related arthritis patients with sacroiliitis.

This study investigated the utility of low-dose CT (ldCT) compared with MRI in diagnosing sacroiliitis in enthesitis-related arthritis (ERA) patients. Thirty patients diagnosed with ERA were evaluated, with a median follow-up of 1.47 years. Images from patients were examined by two paediatric radiologists. For each patient, we assessed the density changes on ldCT at corresponding locations, employing the signal intensity observed on MRI across each joint surface as a reference. While measurements in areas without oedema on MRI showed relatively high density, measurements in areas with oedema on MRI showed relatively low density. MRI revealed bilateral bone marrow oedema in 22 (73.3%) patients. During the ldCT evaluation of the right iliac crest, lower density was identified on ldCT in regions displaying heightened signal intensity on MRI in 20 (66.6%) patients. On the right sacral side, lower density was observed in the ldCT of 22 (73.3%) patients. Moving to the left iliac crest, 18 (60%) patients displayed a lower density. On the left sacral side, lower density was identified on ldCT in 22 (73.3%) patients. Erosion was detected in 23 patients on ldCT, whereas only 11 patients showed erosion on MRI. This study suggests that ldCT is superior to MRI for early structural change detection. Pixel-based density evaluation in ldCT aligns with MRI for bone marrow oedema. The present study showed that ldCT is superior to MRI for early structural change detection. Pixel-based density evaluation in ldCT aligns with MRI findings for bone marrow oedema.

Update on surveillance for Wilms tumor and hepatoblastoma in Beckwith-Wiedemann Syndrome and other predisposition syndromes.

Wilms tumors are commonly associated with predisposition syndromes many, but not all, of which include overgrowth. Several of these syndromes also include a risk of other embryonal malignancies - particularly hepatoblastoma. Guidelines for surveillance in this population were published in 2017 and recently members of the AACR Pediatric Cancer Working Group met to update those guidelines with a review of more recently published evidence and risk estimates. This perspective serves to update pediatric oncologists, geneticists, radiologists, counselors and other healthcare professionals on revised diagnostic criteria, review previously published surveillance guidelines and harmonize updated surveillance recommendations in the North American and Australian context for patients with overgrowth syndromes and other syndromes associated with Wilms tumor predisposition.

Comparison Between Ultrasonography and Radiography in the Detection of Epiphyseal Ossification Centers of the Knee in Infants With Permanent Congenital Hypothyroidism.

To demonstrate the usefulness of ultrasonography in detecting knee ossification centers in infants with permanent congenital hypothyroidism (PCH). From 2011 to 2021, all infants with PCH referred for thyroid ultrasound also underwent left knee ultrasound and radiography on the same day. Knee radiographs were compared with knee sonograms. Two pediatric radiologists reviewed the consensus knee radiographs and sonograms to identify femoral and tibial epiphyseal ossification centers (presence/absence). The concordance between ultrasonography and radiography was assessed. Another radiologist conducted a second late review to evaluate interobserver agreement. We identified 125 patients (65 girls, 60 boys) with a mean age of 24 days (5 days-5 months). On scintigraphy, the thyroid was in place in 66.4%, ectopic in 24%, and absent in 9.6% of patients. The femoral center was observed in 108 patients (86.4%) via sonography and 106 patients (84.8%) via radiography. The tibial center was observed in 84 patients (67.2%) via sonography and radiography. Both femoral and tibial centers were present on sonography and radiography in 84 patients (67.2%). A single nucleus was present in 24 patients (19.2%) on sonography and 22 patients (17.6%) on radiography; it corresponded to the femoral center in all patients. The concordance between ultrasonography and radiography was 99% and 100%, respectively, for the detection of the femoral and tibial centers. Interobserver agreement was substantial to almost perfect for both ultrasonography and radiography. Ultrasonography is as effective as radiography in detecting knee ossification centers in PCH. It can be performed at the same time as thyroid examination, in place of radiography.

Hiding in Plain Sight: Radiologic and Pathologic Findings Can Identify Beckwith-Wiedemann Syndrome in Patients With Wilms Tumor.

Most pediatric specialists, including hematologists/oncologists, surgeons, radiologists, and pathologists, are familiar with the diagnosis and management of Wilms tumor (WT). However, it may be challenging to identify the underlying conditions causing cancer predisposition, which can change the management for the patient and potentially their entire family. In this paper, we present 3 cases of clinically suspected WT associated with Beckwith-Wiedemann syndrome (BWS). We review the radiologic and histologic findings to diagnose BWS. We also discuss the implications of a BWS diagnosis on the clinical management of WT and follow-up guidelines for BWS patients.

Intracranial manifestations of central nervous system tuberculosis in children.

Tuberculosis remains a significant global health challenge, with central nervous system tuberculosis (CNS-TB) posing a substantial threat, accounting for 1-10% of all tuberculosis cases. This article explores the diverse manifestations of CNS-TB in children, with a particular focus on tuberculous meningitis and tuberculomas, as well as their associated complications. Diagnostic imaging, including CT and MRI, plays a crucial role in the early detection of CNS-TB. The article emphasizes the pivotal role of imaging in the diagnosis and management of these manifestations, underscoring the importance of early recognition by healthcare professionals. Ultimately, raising awareness among pediatric radiologists, pediatricians, and pediatric neurologists is crucial for prompt intervention and improved outcomes in cases of CNS-TB.

The Diagnosis and Management of Pediatric Blunt Abdominal Trauma-A Comprehensive Review.

Blunt abdominal trauma in childhood has always been full of diagnostic and therapeutic challenges that have tested the clinical and radiological skills of pediatric surgeons and radiologists. Despite the guidelines and the studies carried out so far, to this day, there is no absolute consensus on certain points of view. Around the world, a paradigm shift towards non-operative treatment of hemodynamically stable children, with low complication rates, is noticeable. Children with blunt abdominal trauma require a standardized methodology to provide the best possible care with the best possible outcomes. This comprehensive review systematizes knowledge about all aspects of caring for children with blunt abdominal trauma, from pre-hospital to post-hospital care.

Performance of Lung-Nodule Computer-Aided Detection Systems on Standard-Dose and Low-Dose Pediatric CT Scans: An Intraindividual Comparison.

Background: When applying lung-nodule computer-aided detection (CAD) systems for pediatric CT, performance may be degraded on low-dose scans due to increased image noise. Objective: To conduct an intraindividual comparison of the performance for lung nodule detection of two CAD systems trained using adult data between low-dose and standard-dose pediatric chest CT scans. Methods: This retrospective study included 73 patients (32 female, 41 male; mean age, 14.7 years; age range, 4-20 years) who underwent both clinical standard-dose and investigational low-dose chest CT examinations within the same encounter from November 30, 2018 to August 31, 2020 as part of an earlier prospective study. Fellowship-trained pediatric radiologists annotated lung nodules to serve as the reference standard. Both CT scans were processed using two publicly available lung-nodule CAD systems previously trained using adult data: FlyerScan and Medical Open Network for Artificial Intelligence (MONAI). The systems' sensitivities for nodules measuring 3-30 mm (n=247) were calculated when operating at a fixed frequency of two false-positives per scan. Results: FlyerScan exhibited detection sensitivities of 76.9% (190/247; 95% CI: 73.3-80.8%) on standard-dose scans and 66.8% (165/247; 95% CI: 62.6-71.5) on low-dose scans. MONAI exhibited detection sensitivities of 67.6% (167/247, 95% CI: 61.5-72.1) on standard-dose scans and 62.3% (154/247, 95% CI: 56.1-66.5%) on low-dose scans. The number of detected nodules for standard-dose versus low-dose scans for 3-mm nodules was 33 versus 24 (FlyerScan) and 16 versus 13 (MONAI), 4-mm nodules was 46 versus 42 (FlyerScan) and 39 versus 30 (MONAI), 5-mm nodules was 38 versus 33 (FlyerScan) and 32 versus 31 (MONAI), and 6-mm nodules was 27 versus 20 (FlyerScan) and 24 versus 24 (MONAI). For nodules measuring ≥7 mm, detection did not show a consistent pattern between standard-dose and low-dose scans for either system. Conclusions: Two lung-nodule CAD systems demonstrated decreased sensitivity on low-dose versus standard-dose pediatric CT scans performed in the same patients. The reduced detection at low dose was overall more pronounced for nodules measuring less than 5 mm. Clinical Impact: Caution is needed when using low-dose CT protocols in combination with CAD systems to help detect small lung nodules in pediatric patients.

MRI features distinguishing pediatric Lyme arthritis from septic arthritis.

This study aims to identify distinguishing MRI features of Lyme arthritis (LA), an increasingly prevalent cause of pediatric infectious arthritis in the USA, to enable rapid discrimination from septic arthritis (SA) and facilitate appropriate management. A single-center, retrospective analysis was conducted on a convenience sample of pediatric patients with LA in an endemic area using EPIC electronic health record data between January 2010 and December 2020. Patients with positive serologic testing and concurrent MRI were selected. MRI scans were reviewed by a subspecialty-trained pediatric radiologist. Key MRI features analyzed include joint effusion, synovitis, myositis, soft tissue edema, and osseous edema and erosions. MRI features, demographics, and clinical data were compared using univariable and multivariable analyses. Fifty cases of knee LA and 13 cases of knee SA were included. Larger joint effusion (p = 0.0055, z = - 2.779) and abnormally thickened synovium (p = 0.0011, χ2 = 10.622) were more associated with LA. In contrast, increased myositis, subcutaneous edema, and osseous changes were more prevalent in SA. Abnormal bone marrow signal (p < 0.0001, χ2 = 36.893) and bone erosion (p < 0.0001, χ2 = 25.506) were observed in 84.6% (11/13) and 46.2% (6/13) of SA cases, respectively, while no bone erosion was found in LA. MRI can be a valuable tool in differentiating LA from SA. Abnormal synovium and increasing joint effusion favor LA, while increasing soft tissue edema and osseous changes favor SA. Notably, the presence of bone erosion effectively excluded LA from consideration.