Retroperitoneal Foregut Duplication Cyst Containing Gastric, Respiratory, and Pancreatic Tissue Misinterpreted as an Adrenal Mass on Imaging: A Case Report and Review of the Literature.

Foregut duplication cyst is most commonly seen in the posterior mediastinum without communication with adjacent organs or presence of other malformations and typically shows ectopic gastric or respiratory epithelium. The finding of ectopic pancreatic tissue is extremely rare. A 15-year-old female patient presented with elevated blood pressure, intermittent right flank pain for 18 months. An abdominal MRI revealed a 4 cm right cystic retroperitoneal mass, initially thought to arise from the right adrenal gland. Intraoperatively, the mass was centered in the retroperitoneum between the right adrenal gland and kidney, without attachments to these organs and no communication with other structures, and it was completely excised. Gross examination revealed a 3.5 cm well-circumscribed solid and cystic mass with orange-white cut surface and cloudy fluid surrounded by variable amounts of adipose tissue. On microscopic examination, the cysts were lined by respiratory and gastric antral/oxyntic-type mucosa, surrounded by muscularis mucosae, submucosal tissue, muscularis propria, and perienteric tissue. Within the muscular propria, exocrine pancreatic tissue was also noted. The patient is well with 7-months of follow up. This case is the first one reporting gastric, respiratory, and pancreatic epithelia.

Neuroendocrine cell hyperplasia of infancy: Feasibility of objective evaluation with quantitative CT.

OBJECTIVE: To describe quantitative CT parameters of children with a typical pattern for NEHI and compare them to controls. MATERIALS AND METHODS: Eleven patients (7 boys) with NEHI and an available chest CT concordant NEHI were identified. Eleven age-, sex-, height-matched, with CT technique-matching were identified for comparison. An open-source software was used to segment the lung parenchyma into lobes using the fissures. Quantitative parameters such as low attenuation areas, mean lung density, kurtosis, skewness, ventilation heterogeneity, lung mass, and volume were calculated for both controls and cases. RESULTS: Analysis of the lung parenchyma showed that patients with NEHI had a lower mean lung density (-615 HU vs -556 HU, p = 0.03) with higher ventilation heterogeneity (0.23 vs 0.19, p = 0.04), lung mass (232 g vs 146 g, p = 0.01) and volume (595 mL vs 339 mL, p = 0.008) compared to controls. Most lobes followed this trend, except the middle lobe that showed only a higher lung mass (32.9 g vs 19.6 g, p = 0.02) and volume (77.4 vs 46.9, p = 0.005) in patients with NEHI compared to controls. CONCLUSION: Quantitative CT is a feasible technique in children with a typical pattern for NEHI and is associated with differences in attenuation, ventilation heterogeneity, and lung volume.

Longitudinal assessment of vascular calcification in generalized arterial calcification of infancy.

BACKGROUND: Generalized arterial calcification of infancy (GACI), also known as idiopathic infantile arterial calcification, is a very uncommon genetic disorder characterized by calcifications and stenoses of large- and medium-size arteries that can lead to end-organ damage. OBJECTIVE: To describe changes in imaging findings in 10 children with GACI at a single institution from 2010 to 2021. MATERIALS AND METHODS: In this retrospective study we reviewed initial and follow-up body imaging in children with genetic confirmation of GACI at our hospital. All initial images were analyzed for the presence and distribution of arterial calcifications, stenoses and wall thickening/irregularity within the chest, abdomen and pelvis. We compared available follow-up studies to the initial imaging findings. We extracted clinical information including prenatal and postnatal treatment from the children's medical records. RESULTS: We evaluated 10 children (five boys) with a diagnosis of GACI. Median age at first body imaging was 8 days (range: 1 day to 5 years). Six children were identified prenatally and four postnatally. Postnatal presentation included cardiac failure, seizures and hypertension. Images in newborns (n = 8) most commonly showed diffuse arterial calcifications (6/8; 75%), while stenoses were less common (2/8; 25%) during this period. Two children were diagnosed after the neonatal period - one in infancy and one during childhood. In total, half the children (5/10; 50%) had arterial stenoses - three cases visualized at first imaging and two identified on follow-up images during infancy. Stenoses had completely resolved in one child (1/5; 20%) at last follow-up. Eight children received prenatal or postnatal treatment or both. All children who received both prenatal and postnatal treatment (n = 4) had completely resolved calcifications at last follow-up. CONCLUSION: Children with GACI might have characteristic vascular calcifications at birth that raise the suspicion of this disease. Arterial calcifications decrease or disappear spontaneously or after treatment, but arterial stenoses usually persist. Calcifications and arterial stenoses can be easily identified and followed with non-contrast CT and CT angiography.

Diffusion Tensor Imaging of the Knee to Predict Childhood Growth.

Background Accurate and precise methods to predict growth remain lacking. Diffusion tensor imaging (DTI) depicts the columnar structure of the physis and metaphyseal spongiosa and provides measures of tract volume and length that may help predict growth. Purpose To validate physeal DTI metrics as predictors of height velocity (1-year height gain from time of MRI examination) and total height gain (height gain from time of MRI examination until growth stops) and compare the prediction accuracy with bone age-based models. Materials and Methods Femoral DTI studies (b values = 0 and 600 sec/mm2; directions = 20) of healthy children who underwent MRI of the knee between February 2012 and December 2016 were retrospectively analyzed. Children with height measured at MRI and either 1 year later (height velocity) or after growth cessation (total height gain, mean = 34 months from MRI) were included. Physeal DTI tract volume and length were correlated with height velocity and total height gain. Multilinear regression was used to assess the potential of DTI metrics in the prediction of both parameters. Bland-Altman plots were used to compare root mean square error (RMSE) and bias in height prediction using DTI versus bone age methods. Results Eighty-nine children (mean age, 13 years ± 3 [SD]; 47 boys) had height velocity measured, and 70 (mean age, 14 years ± 1; 36 girls) had total height gain measured. Tract volumes correlated with height velocity (r2 = 0.49) and total height gain (r2 = 0.46) (P < .001 for both) after controlling for age and sex. Tract volume was the strongest predictor for height velocity and total height gain. An optimal multilinear model including tract volume improved prediction of height velocity (R2 = 0.63, RMSE = 1.7 cm) and total height gain (R2 = 0.59, RMSE = 1.8 cm) compared with bone age-based methods (height velocity: R2 = 0.32, RMSE = 2.9 cm; total height gain: R2 = 0.42, RMSE = 5.0 cm). Conclusion Models using tract volume derived from diffusion tensor imaging may perform better than bone age-based models in children for the prediction of height velocity and total height gain. © RSNA, 2022.

Voxel-based map of the inter-arterial watershed zones in children.

PURPOSE: To create a voxel-based map of the inter-arterial watershed derived from children who have sustained a hypoxic-ischemic injury involving this region at term. MATERIALS AND METHODS: Patients 0-18 years of age diagnosed with a hypoxic-ischemic injury of the watershed on magnetic resonance imaging (MRI) were included. Two pediatric neuroradiologists segmented the lesions as visualized on the T2-weighted sequence. All lesion maps were normalized to a brain template and overlapped to create a frequency map in order to highlight the frequency of involvement of portions of the cortical watershed. RESULTS: A total of 47 patients (35 boys) were included in the final sample. Their mean age was 7.6 ± 3.6 years. The cortical watershed was successfully mapped. Three watershed regions were defined: the anterior, peri-Sylvian, and posterior watershed zones. The anterior and peri-Sylvian watershed zones are connected through the involvement of the middle frontal gyrus. The peri-Sylvian and the posterior watershed zones are connected through the involvement of the inferior parietal lobule, the posterior aspect of the superior temporal gyrus, and the angular gyrus with the occipital lobe. The temporal lobe and orbital part of the frontal lobe are largely spared in all patients. CONCLUSION: A voxel-based lesion map of children with watershed hypoxic ischemic injury at term was created and three inter-arterial watershed zones defined: anterior, peri-Sylvian, and posterior watersheds.

Value of chest CT over skeletal surveys in detection of rib fractures in pediatric patients.

Recent literature has raised concerns about the sensitivity and accuracy of radiographs at diagnosing rib fractures. Studies have shown that chest computed tomography (CT) has far greater sensitivity at detecting rib fractures than radiographs. The purpose of this study was to evaluate the sensitivity of skeletal survey (SS) radiographs at diagnosis of rib fractures compared to CT in the pediatric population. This retrospective review included 57 patients who had undergone both a SS and a CT chest or CT chest/abdomen/pelvis within 30 days of each other for the indication of either non-accidental (NAT) or accidental trauma between 2009 and 2017. Images and reports were analyzed by a pediatric radiology fellow for presence/absence of fracture, evidence of healing and location of rib fracture, including rib level, location within the rib (anterior, lateral, and posterior), and side (right versus left). 225 rib fractures were identified in 25 patients on CT. 38 of those fractures were missed on the preceding SS, yielding a miss rate of 17%. Acute fractures were more likely to be missed than chronic or healing fractures (p ≤ 0.01). Location within the rib did not impact rib detection on radiographs. Left-sided rib fractures were not more common in NAT patients, compared to accidental trauma. SS miss approximately 17% of all rib fractures and CT is more sensitive modality in the detection of rib fractures, particularly acute rib fractures, regardless of location. Low-dose Chest CT could be a helpful modality in the work-up of NAT trauma.

Pilot study for comparative assessment of dual-energy computed tomography and single-photon emission computed tomography V/Q scanning for lung perfusion evaluation in infants.

OBJECTIVE: To evaluate clinical applications of dual-energy computed tomography (DECT) in pediatric-specific lung diseases and compare ventilation and perfusion findings with those from single-photon emission computed tomography (SPECT-CT) V/Q. METHODS: All patients at our institution who underwent exams using both techniques within a 3-month period were included in this study. Two readers independently described findings for DECT, and two other readers independently analyzed the SPECT-CT V/Q scan data. All findings were compared between readers and disagreements were reassessed and resolved by consensus. Inter-modality agreements are described throughout this study. RESULTS: Eight patients were included for evaluation. The median age for DECT scanning was 3.5 months (IQR = 2). Five of these patients were scanned for both DECT and SPECT-CT V/Q studies the same day, and three had a time gap of 7, 65, and 94 days between studies. The most common indications were chronic lung disease (5/8; 63%) and pulmonary hypertension (6/8; 75%). DECT and SPECT-CT V/Q identified perfusion abnormalities in concordant lobes in most patients (7/8; 88%). In one case, atelectasis limited DECT perfusion assessment. Three patients ultimately underwent lobectomy with corresponding perfusion abnormalities identified by all reviewers on both DECT and SPECT-CT V/Q in all resected lobes. CONCLUSION: DECT is a feasible technique that could be considered as an alternative for SPECT-CT V/Q for lung perfusion evaluation in infants.

The Use of Point-of-Care Ultrasound (POCUS) in the Diagnosis of Deep Vein Thrombosis.

Acute lower extremity proximal deep venous thrombosis (DVT) requires accurate diagnosis and treatment in order to prevent embolization and other complications. Point-of-care ultrasound (POCUS), a clinician performed, and clinician interpreted bedside ultrasound examination has been increasingly used for DVT evaluation mainly in the urgent and critical care setting, but also in the ambulatory clinics and the medical wards. Studies have demonstrated that POCUS has excellent diagnostic accuracy for acute proximal DVT when performed by well-trained users. However, there is significant heterogeneity among studies on the necessary extent of training and universally acceptable standardized education protocols are needed. In this review, we summarize the evidence that supports the use of POCUS to diagnose acute proximal DVT and focus on methodology and current technology, sensitivity and specificity, pre-test probability and the role of D-dimer, time and resources, education, limitations, and future directions.

Prognostic value of the nutmeg lung pattern/lymphangiectasia on fetal magnetic resonance imaging.

BACKGROUND: A nutmeg lung pattern on magnetic resonance imaging (MRI) is an imaging finding associated with pulmonary lymphangiectasia. However, the prognostic value of the nutmeg lung pattern is unknown. OBJECTIVE: To evaluate the clinical associations of nutmeg lung indicating lymphangiectasia on fetal lung MRI and its relationship with early mortality in fetuses with primary and secondary lymphangiectasia. MATERIALS AND METHODS: We retrospectively identified all pregnant patients with a fetal MRI performed for indication of evaluating for pulmonary lymphangiectasia from 2006 to 2019. Two readers evaluated the fetal MRIs and interobserver agreement was calculated. Multivariable logistic regression models were performed to estimate the association of the echocardiographic findings and the presence of nutmeg lung. Kaplan-Meier and Cox regression analyses were performed to evaluate association with mortality in the first 30 days of life. Survival analysis was defined as mortality or orthotopic heart transplant at 30 days of age. P<0.05 was considered significant. RESULTS: Our sample included 53 fetuses. Forty-seven (89%) had congenital heart disease (CHD) and 6 (11%) were diagnosed postnatally with primary lymphangiectasia. Interobserver agreement was 0.83. Pulmonary vein congestion on echocardiography was the strongest predictor of nutmeg lung (odds ratio [OR]=12.0, P=0.002). Ten fetuses reached the outcome of heart transplantation (n=1) or death (n=9) within the first 30 days of life. In fetuses with CHD, survival of those with nutmeg lung was significantly lower than in those without (P<0.001). Nutmeg lung was an independent risk factor for 30-day mortality (hazard ratio [HR]: 6.1, P=0.01). CONCLUSION: Nutmeg lung pattern on fetal MRI is an independent risk factor associated with 30-day mortality in fetuses with CHD.

Humeral lesser tuberosity avulsion fractures - magnetic resonance imaging characteristics in the pediatric population.

BACKGROUND: Avulsion fractures of the humeral lesser tuberosity are rare injuries in skeletally immature patients and can pose a diagnostic challenge that often leads to delayed identification. OBJECTIVE: To describe the demographics, mechanism of injury and magnetic resonance imaging (MRI) findings of lesser tuberosity avulsion fractures in children. MATERIALS AND METHODS: A retrospective search of children with lesser tuberosity avulsion fractures on MRI was done. Available radiographs were evaluated. Demographics, mechanism of injury, MRI characteristics and treatment were recorded. RESULTS: Thirteen children, all male, were included (median age: 13.8 years, range: 12.5-16.8 years). The most common mechanism was blunt, overhead or hyperextension traumatic injury related to sports. All patients were skeletally immature and 10/13 demonstrated isolated avulsion fractures at the footprint. Only one patient had associated osteochondral injury to the humeral head and labral tear. Two children demonstrated medial dislocation/subluxation of the biceps tendon. The median size of the avulsed fragment was 15 mm (range: 5-29 mm), median anteroposterior displacement was 3 mm (range: 0-6 mm) and medial displacement was 1 mm (range: 0-20 mm). There was no correlation between age and the size of the avulsed fragment (P=0.29). Common injury patterns were complete avulsion of the subscapularis footprint (6/13) and partial avulsion of inferior footprint (6/13). Two-thirds of the radiographs were initially reported as normal, but retrospectively showed two missed fractures. One of the initial radiographs raised concern for bone tumor. The best view for identifying an avulsion fragment was the axillary view. Seven patients of the 13 patients underwent internal fixation. CONCLUSION: Avulsion fractures of the lesser tuberosity are rare, challenging to diagnose and often radiographically occult. MRI can identify the injury at the subscapularis tendon footprint with variable size and displacement. The long head of the biceps tendon is usually normal in location. Although this entity is rare, radiologists should be aware of it to allow for correct and prompt diagnosis and prevent unnecessary biopsy or contrast administration.

Normal age-related quantitative CT values in the pediatric lung: from the first breath to adulthood.

OBJECTIVE: To characterize the normal progression of quantitative CT parameters in normal children from birth to adulthood. MATERIALS AND METHODS: Patients aged 0-18 years with non-contrast-enhanced chest CT and evidence of normal lung parenchyma were included. Patients with respiratory symptoms, incomplete anthropometric measurements, or sub-optimal imaging technique were excluded. Segmentation was performed using an open-source software with an automated threshold segmentation. The following parameters were obtained: mean lung density, kurtosis, skewness, lung volume, and mass. Linear and exponential regression models were calculated with age and height as independent variables. A p-value of <0.05 was considered significant. RESULTS: 220 patients (111 females, 109 males) were included. Mean age was 9.6 ± 5.9 years and mean height was 133.9 ± 35.1 cm. Simple linear regression showed a significant relationship between mean lung density with age (R 2 = 0.70) and height (R 2 = 0.73). Kurtosis displayed a significant exponential correlation with age (R 2 = 0.70) and height (R 2 = 0.71). Skewness showed a significant exponential correlation with age (R 2 = 0.71) and height (R 2 = 0.73). Lung mass showed a correlation with age (R 2 = 0.93) and height (R 2 = 0.92). Exponential regression showed a significant relationship between lung volume with age (R 2 = 0.88) and height (R 2 = 0.93). CONCLUSION: Quantitative CT parameters of the lung parenchyma demonstrate changes from birth to adulthood. As children grow, the mean lung density decreases, and the lung parenchyma becomes more homogenous.

CTA utilization for evaluation of suspected pulmonary embolism in a tertiary pediatric emergency department.

OBJECTIVE: To evaluate changes in the utilization of computed tomography angiography (CTA) for evaluating suspected pulmonary embolism (PE) and the positive rate of ancillary for those studies negative for PE in the last 13 years. MATERIALS AND METHODS: A retrospective review of patient ≤ 20 years of age who underwent a chest CT angiography to rule out PE was performed in a 13-year-period. CT angiographies were grouped into three categories: Positive for PE, negative for PE and positive for ancillary findings, and negative for any pathology. From the exams with ancillary findings, we examined how many of these had a chest radiograph perform within 24 h prior to the CTA and how many of them had an impression stating the same conclusion as the CTA. RESULTS: 307 chest CT angiographies for suspected PE were included. 50 (16%) were reported as positive for PE and 91 (30%) were negative for PE but positive for ancillary findings. The most frequent ancillary findings were pneumonia (n = 26) and pleural effusion (n = 11). Out of 91, 73 patients had a previous chest radiograph and 28 of them reported a similar diagnosis than the CTA. The number of CT angiographies indicated for PE increased by 3.2 studies per year. The rate of CT angiographies positive for ancillary findings (slope = 1.5) and positive for PE (slope = 0.3) remained similar throughout the same period. CONCLUSIONS: CTA orders for PE have been increasing without any increased detection of PE or ancillary findings in children.

Imaging of children with COVID-19: experience from a tertiary children's hospital in the United States.

BACKGROUND: Imaging of novel coronavirus disease 2019 (COVID-19) has been described in adults, but children have milder forms of disease. Pediatric imaging descriptions are of asymptomatic children, raising the question of whether imaging is needed in this patient group. OBJECTIVE: To describe the utilization and imaging findings in children with COVID-19 along with the comorbidities, treatment and short-term outcomes. MATERIALS AND METHODS: We retrospectively reviewed pediatric patients who had a confirmed positive test for COVID-19 during a 2-month period. We noted symptoms and presence of imaging at presentation. Comorbidities were recorded for children with imaging. Children were categorized as having multisystem inflammatory syndrome in children (MIS-C) if they met criteria for the disorder. For children who were admitted to the hospital, we documented length of hospital stay, need for intensive care unit care/ventilator support, and treatment regimen. We evaluated all imaging for acute/chronic abnormalities including chest radiographs for interstitial or alveolar opacities, distribution/symmetry of disease, zonal predominance, and pleural abnormalities. We performed descriptive statistics and compared children with MIS-C with the cohort using a Fisher exact test. RESULTS: During the study period, 5,969 children were tested for COVID-19, with 313 (5%) testing positive. Of these, 92/313 (29%) were asymptomatic and 55/313 (18%) had imaging and were admitted to the hospital for treatment. Forty-one of 55 patients (75%) with imaging had comorbidities. Chest radiographs were the most common examination (51/55 patients, or 93%) with most demonstrating no abnormality (34/51, or 67%). Children with MIS-C were more likely to have interstitial opacities and pleural effusions. US, CT or MRI was performed in 23/55 (42%) children, 9 of whom had MIS-C. Only one chest CT was performed. CONCLUSION: In our study, most pediatric patients with COVID-19 did not require hospital admission or imaging. Most children with imaging had comorbidities but children with MIS-C were more likely to have no comorbidities. Children with imaging mostly had normal chest radiography. Advanced imaging (US, CT, MRI) was less common for the care of these children, particularly CT examination of the chest and for children without MIS-C.

Developmental dysplasia of the hip: can contrast-enhanced MRI predict the development of avascular necrosis following surgery?

OBJECTIVE: To investigate the performance of contrast-enhanced MRI for predicting avascular necrosis (AVN) of the treated femoral head after surgical reduction for developmental dysplasia of the hip (DDH) using qualitative and quantitative methods. METHODS AND MATERIALS: This IRB-approved, HIPAA compliant retrospective study included 47 children who underwent same-day contrast-enhanced MRI following unilateral surgical hip reduction between April 2009 and June 2018. Blinded to the clinical outcome, 3 reviewers (2 pediatric radiologists and 1 pediatric orthopedist) independently categorized the enhancement pattern of the treated femoral head. Signal intensities, measured using regions of interest (ROI), were compared between treated and untreated hips and percent enhancements were compared between hips that developed and did not develop AVN. Post-reduction radiographs were evaluated using Salter's criteria for AVN and Kalmachi and MacEwen's classification for growth disturbance. Non-parametric tests and Fisher exact test were used to compare enhancement values between AVN and non-AVN hips. Bonferroni correction was used for multiple comparisons. RESULTS: Ten (21%) out of the 47 children (7 boys and 40 girls; mean age 9.0 ± 4.7 months) developed AVN. Age at surgical reduction was significantly higher (p = 0.03) for hips that developed AVN. No significant differences were found in gender (p = 0.61), laterality (p = 0.46), surgical approach (p = 0.08), history of pre-operative bracing (p = 0.72), abduction angle (p = 0.18-0.44), enhancement pattern (p = 0.66-0.76), or percent enhancement (p = 0.41-0.88) between AVN and non-AVN groups. CONCLUSION: Neither enhancement pattern nor percent enhancement predicted AVN, suggesting that post-reduction conventional MRI does not accurately distinguish between reversible and permanent vascular injury.

Imaging of fetal lymphangiectasias: prenatal and postnatal imaging findings.

Lymphangiectasias are lymphatic malformations characterized by the abnormal dilation and morphology of the lymphatic channels. The classification and treatment of these disorders can be challenging given the limited amount of literature available in children. Various imaging modalities are used to confirm suspected diagnosis, plan the most appropriate treatment, and estimate a prognosis. Prenatal evaluation is performed using both prenatal US imaging and fetal MRI. These modalities are paramount for appropriate parental counseling and planning of perinatal care. During the neonatal period, chest US imaging is a useful modality to evaluate pulmonary lymphangiectasia because other modalities such as conventional radiography and CT display nonspecific findings. Finally, the recent breakthroughs in lymphatic imaging with MRI have allowed us to better classify lymphatic disorders. Dynamic contrast-enhanced lymphangiography, conventional lymphangiography and percutaneous lymphatic procedures offer static and dynamic evaluation of the central conducting lymphatics in children, with excellent spatial resolution and the possibility to provide treatment. The purpose of this review is to discuss the normal and abnormal development of the fetal lymphatic system and how to best depict it by imaging during the prenatal and postnatal life.

Current and Future Applications of Thoracic Dual-Energy CT in Children: Pearls and Pitfalls of Technique and Interpretation.

Dual-energy computer tomography (DECT) technology has experienced rapid growth in recent years, now allowing for the collection of 2 CT data sets and opening the potential for functional data acquisition. Data from a single postcontrast phase are deconstructed and Iodine can be subtracted to create a virtual noncontrast image, or selectively represented as a contrast map that allows for the qualification and quantification of lung perfusion. Virtual monoenergetic images can also be used to reduce beam-hardening artifact from concentrated contrast or metal implants. In children, DECT is of particular interest because it has been shown to be dose neutral in most applications, dose-reducing in multiphase studies, and to increase the contrast to noise ratio in suboptimal studies. We review the basics of acquisition, postprocessing, and thoracic applications of DECT with a focus on pulmonary blood volumes as a surrogate for perfusion imaging. The discussed applications include pulmonary embolism, hypoplastic lung, pulmonary hypertension in bronchopulmonary dysplasia, and pediatric lung masses.