Zero-echo time MRI: an alternative method for the diagnosis of urinary stones in children.

OBJECTIVES: To evaluate the potential of zero-echo time-magnetic resonance imaging (ZTE-MRI) in the assessment of urolithiasis and compare ZTE-MRI with computed tomography (CT) in pediatric patients. MATERIALS AND METHODS: This was a single-center, prospective cross-sectional study conducted between April 2023 and December 2023. 23 patients (12 girls, 11 boys; mean age: 12.3, range 1-18) with urinary tract stones detected on non-enhanced abdominal CT were enrolled. The images were evaluated independently by two radiologists for the presence, and number of stones in the kidneys, ureters, and bladder. In the second session, two radiologists evaluated whether urinary tract stones could be detected by MRI compared to CT, and the maximum diameter of the stones was measured. The CT and MRI results were compared with the Wilcoxon test. The agreement between the results of the observers was examined using Spearman's rho correlation coefficient and the intraclass correlation coefficient. RESULTS: A total of 58 urinary tract stones were detected by CT and 39 of these were detected by MRI. Most of the stones that MRI could not detect were < 5 mm and the detection sensitivity of MRI increased in correlation with stone size (p < 0.001). There was poor intermodality agreement for stones < 5 mm, substantial agreement for stones 5-10 mm, and almost perfect agreement for stones > 10 mm. Interobserver agreement for stone detection on MRI was almost perfect for stones > 10 mm and 5-10 mm and was substantial for stones < 5 mm. CONCLUSION: ZTE-MRI is a promising modality for detecting urinary stones without radiation exposure in children. CLINICAL RELEVANCE STATEMENT: Zero-echo time-magnetic resonance imaging is a potential method for identifying urinary stones in children and other populations who are particularly sensitive to radiation. KEY POINTS: Urinary system stone disease in children is increasing and imaging is needed for managing urolithiasis. Zero-echo time-magnetic resonance imaging (ZTE-MRI) had an accuracy of 81.8% and 93.7% for stones larger than 5 mm and 10 mm, respectively. ZTE-MRI is a potential non-irradiating method for the diagnosis and management of urolithiasis.

Imaging findings of primary lung tumors in children.

PURPOSE: Pediatric lung tumors are primarily discussed in the surgical literature. However, limited research has been reported on their imaging findings, and only a few tumor types have been documented. Therefore, the aim of this article is to describe the imaging features of primary lung tumors in children. METHODS: The archives of the pediatric radiology unit were reviewed for primary lung tumors documented between 2007 and 2023. In total, 24 patients (9 girls and 15 boys; aged 5 months to 16 years) were included in the study. Their demographic characteristics, clinical presentation, and histopathologic results were obtained. All imaging studies were reviewed by two radiologists for various findings (e.g., lymphadenopathy, atelectasis, pleural effusion, calcification, multiplicity, pneumothorax, axial and lobar location, laterality, tumor margin, mediastinal shift, contrast enhancement pattern, signal intensity on T1- and T2-weighted images, and diffusion pattern), and a final decision was made by consensus. The mean tumor size was compared between the benign and malignant groups using a t-test. RESULTS: There were 15 (62.5%) benign tumors, as follows: inflammatory myofibroblastic tumor (IMT; n = 10, 41%), hemangioma (n = 2, 8%), pneumocytoma (n = 2, 8%), and mature cystic teratoma (n = 1, 4%). Moreover, there were 9 (37.5%) malignant tumors, as follows: pleuropulmonary blastoma (PPB; n = 6, 25%), adenocarcinoma (n = 2, 8%), and lymphoepithelioma-like carcinoma (LELC) (n = 1, 4%). The most frequently reported symptoms were cough, fever, dyspnea, chest pain, and recurrent infection; six patients reported no clinical symptoms. Fifteen tumors (62%) were located in the right lung. The mean tumor diameter at the time of diagnosis was 6.4 ± 3 cm (benign group: 6.7 ± 3.4 cm; malignant group: 6 ± 2.3 cm, P > 0.050). Calcification was present in 80% of the patients with IMT. At the time of diagnosis, two (8.3%) patients were found to have metastasis: one was diagnosed with adenocarcinoma and the other with LELC. Tumors were located peripherally in 18 (75%) patients. CONCLUSION: The symptoms associated with lung masses are non-specific. There is no correlation between tumor size and malignancy. The most common tumors observed in this study were IMT and PPB, respectively. IMT is highly associated with calcification. CLINICAL SIGNIFICANCE: Primary lung tumors are rarely seen in children, and they have different histopathological types. Calcification might be an important radiological clue for the diagnosis of IMT, which is the most common lung tumor in children.

The role of malnutrition on outcomes of multisystem inflammatory syndrome in children (MIS-C) due to COVID-19.

BACKGROUND: Malnutrition increases the complications and mortality in critically-ill children. We performed a retrospective analysis to define the impact of malnutrition on the outcomes of multisystem inflammatory syndrome in children (MIS-C) due to COVID-19. METHODS: Patients with MIS-C were evaluated for demographic features, anthropometric parameters, clinical findings and outcomes. Patients with z scores of body mass index (> 5 years) and weight-for-age (< 5 years) < -2 were considered malnourished. Sarcopenia was defined by total psoas muscle area (tPMA), calculated on abdominal computed tomography (CT) at the level of L3 and L4 vertebrae. The z scores <- 2 for tPMA were considered sarcopenia. The results of patients with and without malnutrition were compared. RESULTS: Twenty-seven patients were included. Forty-four percent (n=12) of patients had malnutrition. Malnutrition was classified as mild to moderate (1/3), severe (1/3) and overweight (1/3). Eighty-two % of cases had acute malnutrition. Among MIS-C symptom criteria, rash was significantly higher in children with malnutrition (p<0.05). Laboratory investigations showed higher ferritin levels in patients with malnutrition (p<0.05). The median tPMA and sarcopenia were significantly higher in patients with malnutrition when compared to patients without malnutrition (42% vs 7%, p<0.05). The oral feeding time, complication rates, and length of hospital stay were similar in both groups (p>0.05). CONCLUSION: Children with MIS-C already had mild to severe malnutrition at admission. Rash and higher ferritin levels were more common in patients with malnutrition. In addition to anthropometric parameters, sarcopenia calculated using tPMA can be used to predict malnutrition in critically-ill children.

Update on imaging recommendations in paediatric uroradiology: the European Society of Paediatric Radiology workgroup session on voiding cystourethrography.

Voiding cystourethrography (VCUG) is a fluoroscopic technique that allows the assessment of the urinary tract, including the urethra, bladder, and-if vesicoureteral reflux (VUR) is present-the ureters and the pelvicalyceal systems. The technique also allows for the assessment of bladder filling and emptying, providing information on anatomical and functional aspects. VCUG is, together with contrast-enhanced voiding urosonography (VUS), still the gold standard test to diagnose VUR and it is one of the most performed fluoroscopic examinations in pediatric radiology departments. VCUG is also considered a follow-up examination after urinary tract surgery, and one of the most sensitive techniques for studying anatomy of the lower genitourinary tract in suspected anatomical malformations. The international reflux study in 1985 published the first reflux-protocol and graded VUR into five classes; over the following years, other papers have been published on this topic. In 2008, the European Society of Paediatric Radiology (ESPR) Uroradiology Task Force published the first proposed VCUG Guidelines with internal scientific society agreement. The purpose of our work is to create a detailed overview of VCUG indications, procedural recommendations, and to provide a structured final report, with the aim of updating the 2008 VCUG paper proposed by the European Society of Paediatric Radiology (ESPR). We have also compared VCUG with contrast-enhanced VUS as an emergent alternative. As a result of this work, the ESPR Urogenital Task Force strongly recommends the use of contrast-enhanced VUS as a non-radiating imaging technique whenever indicated and possible.

Radiomics in differential diagnosis of Wilms tumor and neuroblastoma with adrenal location in children.

OBJECTIVES: Machine learning methods can be applied successfully to various medical imaging tasks. Our aim with this study was to build a robust classifier using radiomics and clinical data for preoperative diagnosis of Wilms tumor (WT) or neuroblastoma (NB) in pediatric abdominal CT. MATERIAL AND METHODS: This is a single-center retrospective study approved by the Institutional Ethical Board. CT scans of consecutive patients diagnosed with WT or NB admitted to our hospital from January 2005 to December 2021 were evaluated. Three distinct datasets based on clinical centers and CT machines were curated. Robust, non-redundant, high variance, and relevant radiomics features were selected using data science methods. Clinically relevant variables were integrated into the final model. Dice score for similarity of tumor ROI, Cohen's kappa for interobserver agreement among observers, and AUC for model selection were used. RESULTS: A total of 147 patients, including 90 WT (mean age 34.78 SD: 22.06 months; 43 male) and 57 NB (mean age 23.77 SD:22.56 months; 31 male), were analyzed. After binarization at 24 months cut-off, there was no statistically significant difference between the two groups for age (p = .07) and gender (p = .54). CT clinic radiomics combined model achieved an F1 score of 0.94, 0.93 accuracy, and an AUC 0.96. CONCLUSION: In conclusion, the CT-based clinic-radiologic-radiomics combined model could noninvasively predict WT or NB preoperatively. Notably, that model correctly predicted two patients, which none of the radiologists could correctly predict. This model may serve as a noninvasive preoperative predictor of NB/WT differentiation in CT, which should be further validated in large prospective models. CLINICAL RELEVANCE STATEMENT: CT-based clinic-radiologic-radiomics combined model could noninvasively predict Wilms tumor or neuroblastoma preoperatively. KEY POINTS: • CT radiomics features can predict Wilms tumor or neuroblastoma from abdominal CT preoperatively. • Integrating clinic variables may further improve the performance of the model. • The performance of the combined model is equal to or greater than human readers, depending on the lesion size.

Pancake kidney and jejunal atresia: An uncommon dual anomaly detected prenatally-A case report.

Pancake kidney is a renal fusion anomaly with only a few reported prenatal diagnoses. Other structural anomalies beyond the urogenital system may also be associated. This study describes a dual anomaly case detected prenatally, comprising of pancake kidney and jejunal atresia. A postnatal abdominal ultrasound confirmed both kidneys were fused in the midline at the aortic bifurcation level, along with a type 3b jejunal atresia. Based on the available limited evidence about pancake kidney, renal functions appear to remain largely preserved and unaffected as in our case according to 6 months of follow-up. However, further investigation is needed to explore any potential association with chromosomal and structural abnormalities in selected cases.

Focal fatty sparing areas of the pediatric steatotic liver: pseudolesions on hepatobiliary phase magnetic resonance images.

PURPOSE: Focal fatty sparing in liver can be detected as hyperintense pseudolesions on hepatobiliary phase magnetic resonance imaging (MRI). Distinguishing these pseudolesions from liver lesions may make diagnosis challenging. The aim of this study was to evaluate the imaging features of fatty sparing areas on liver MRI in pediatric patients who have been administered gadoxetate disodium. METHODS: A total of 63 patients between January 2018 and June 2023 underwent gadoxetate disodium-enhanced liver MRI, and 9 (14%) patients with a focal fatty sparing were included in the study. The fat spared areas were evaluated qualitatively and quantitatively including signal intensity measurements and fat fraction calculations. RESULTS: The liver MRI examinations of 9 patients (5 boys, 4 girls; aged 8-18 years, median age: 14.4) using gadoxetate disodium were evaluated. Based on in-phase and opposed-phase sequences, 13 areas of focal fatty sparing were identified. The mean fat fraction of the liver and fat spared areas were 26.2% (range, 15-47) and 9% (range, 2-17), respectively. All fat spared areas were hyperintense in the hepatobiliary phase images. The mean relative enhancement ratios of the liver and fat spared areas were 0.78 (range, 0.35-1.6) and 1.11 (range, 0.45-1.9), respectively. CONCLUSION: Focal fatty sparing in liver in children was observed as hyperintense on hepatobiliary phase MRI, and it should not be identified as a focal liver lesion.

Liver magnetic resonance elastography and fat fraction in pediatric patients with cystic fibrosis versus healthy children.

BACKGROUND: Liver involvement is an important cause of morbidity and mortality in patients with cystic fibrosis (CF). While liver biopsy is the gold standard for demonstrating involvement, its invasiveness prompts a search for noninvasive alternatives. OBJECTIVE: To evaluate liver involvement in pediatric patients with CF (versus healthy controls) using magnetic resonance (MR) elastography/spectroscopy and to correlate the imaging findings with clinical/laboratory characteristics. MATERIALS AND METHODS: This was a single-center, prospective cross-sectional study conducted between April 2020 and March 2022 in patients with CF versus healthy controls. Patients with CF were divided into two subgroups: those with CF-related liver disease and those without. MR images were acquired on a 1.5-tesla machine. Kilopascal (kPa) values were derived from processing MR elastography images. MR spectroscopy was used to measure liver fat fraction, as an indication of hepatosteatosis. Groups were compared using either the Student's t test or the Mann‒Whitney U test. The chi-square test or Fisher's exact test were used to compare qualitative variables. RESULTS: Fifty-one patients with CF (12 ± 3.3 years, 32 boys) and 24 healthy volunteers (11.1 ± 2.4 years, 15 boys) were included in the study. Median liver stiffness (P=0.003) and fat fraction (P=0.03) were higher in the CF patients than in the controls. Median liver stiffness values were higher in CF patients with CF-related liver disease than in those without CF-related liver disease (P=0.002). Liver stiffness values of CF patients with high alanine aminotransferase (ALT), high gamma-glutamyl transferase, and thrombocytopenia were found to be higher than those without (P=0.004, P<0.001, P<0.001, respectively). Only the high ALT group showed a high fat fraction (P=0.002). CONCLUSIONS: Patients with CF had higher liver stiffness than the control group, and patients with CF-related liver disease had higher liver stiffness than both the CF patients without CF-related liver disease and the control group. Patients with CF had a higher fat fraction than the control group. Noninvasive assessment of liver involvement using MR elastography/spectroscopy can support the diagnosis of CF-related liver disease and the follow-up of patients with CF.

Imaging Features of Pediatric Sarcoidosis.

Sarcoidosis is a granulomatous inflammatory disease of uncertain cause. It occurs most commonly in young and middle-aged adults and less frequently in children; therefore, few data on pediatric sarcoidosis exist in the literature. The diagnosis and management of sarcoidosis remain challenging because of diverse and often nonspecific clinical and imaging findings. In addition, the clinical picture varies widely by age. Prepubertal and adolescent patients often present with adult-like pulmonary disease; however, early-onset sarcoidosis is typically characterized by the triad of arthritis, uveitis, and skin rash. Sarcoidosis is mostly a diagnosis of exclusion made by demonstrating noncaseating granulomas at histopathologic examination in patients with compatible clinical and radiologic findings. Although sarcoidosis often affects the lungs and thoracic lymph nodes, it can involve almost any organ in the body. The most common radiologic manifestation is pulmonary involvement, characterized by mediastinal and bilateral symmetric hilar lymphadenopathies with perilymphatic micronodules. Abdominal involvement is also common in children and often manifests as hepatomegaly, splenomegaly, and abdominal lymph node enlargement. Although neurosarcoidosis and cardiac sarcoidosis are rare, imaging is essential to the diagnosis of central nervous system and cardiac involvement because of the risky biopsy procedure and its low diagnostic yield due to focal involvement. Being familiar with the spectrum of imaging findings of sarcoidosis may aid in appropriate diagnosis and management. ©RSNA, 2023 Test Your Knowledge questions are available in the supplemental material.

Effect of prostaglandin-E1 treatment on pyloric wall thickness in newborns with ductal-dependent critical congenital heart diseases.

BACKGROUND: Prostaglandin E1 (PGE1) is used in the medical treatment of ductal-dependent critical congenital heart disease (CCHD) in neonates. Apnea/bradycardia, hypotension, hypokalemia, and fever are the most important side effects of PGE1. Moreover, gastric outlet obstruction has been reported in a few case reports. A prospective study was conducted to investigate the effect of PGE1 treatment on pyloric wall thickness in newborns with congenital heart diseases. METHODS: A total of 22 newborns with ductal-dependent CCHD having PGE1 infusion longer than a week were included in this study. Ultrasonographic measurements were performed before and one week after the PGE1 infusion to evaluate the pyloric thickness and length. The protocol was registered with ClinicalTrials.govidentifier NCT04496050. RESULTS: A total of 22 neonates with mean gestational age 38 ± 1.8 weeks and birth weight 3105 ± 611 gr were enrolled in the study. The median time of the second ultrasound was seven days. The median cumulative dose of PGE1 given during this period was 108 mcg/kg/min. There was a statistically significant increase in post-treatment pyloric thickness and length compared to pre-treatment measurements (p < 0.001, p < 0.001). None of the patients with increased thickness and pyloric muscle length presented any symptoms. CONCLUSION: PGE1 treatment significantly increased the pyloric thickness and length after at least one-week treatment. PGE1 with its action mechanism is likely to cause gastric outlet obstruction, although not exactly pyloric stenosis on the condition used for a long time.

Evaluation of Clinical Findings in Children with Chylothorax: A Descriptive Study.

OBJECTIVE: Chylothorax refers to the presence of chyle in the pleural space. There are multiple etiologies of chylothorax. Our aim in this study was to evaluate the clinical manifestations, causes, and treatment of chylothorax in childhood and also to show the differences between the 2 age groups admitted to a tertiary care children's hospital. The second aim was to evaluate the clinical and radiologic features of patients diagnosed as having Gorham-Stout disease via chylothorax. MATERIALS AND METHODS: The archives were reviewed for chylothorax documented in the last 31 years. Twenty-two patients (11 girls and 11 boys) were included. Patients were divided into 2 groups: the younger group aged under 24 months and the older group aged over 24 months. RESULTS: A total of 22 patients had chylothorax, and 10 were aged younger than 24 months. In the younger group, etiologies were in order congenital heart surgery, congenital chylothorax, and Gorham-Stout disease. In the older group, etiologies were Gorham-Stout disease, congenital heart surgery, heart failure, heart transplantation, thrombus, intestinal lymphangiectasia, and idiopathic. The most common treatment in the younger group was the medium-chain triglyceride diet (70%), and in the older group, it was sirolimus (50%). CONCLUSION: There is a wide variety of underlying etiologies in childhood, so a multidisciplinary approach is important to identify the underlying diagnosis. The common etiologies were postoperative and Gorham-Stout disease in our study. All patients with Gorham-Stout disease had a good prognosis. Gorham-Stout disease should be considered in patients of any age with a diagnosis of chylothorax who have bone lesions.

A new tool supporting the diagnosis of childhood-onset Behçet's disease: venous wall thickness.

OBJECTIVES: The lower extremity venous wall thickness (VWT) of Behçet's disease (BD) patients was reported to be significantly increased in adults, suggesting its use for the support of BD diagnosis. This prospective study aimed to investigate the lower extremity VWT in childhood-onset definite and incomplete BD patients and compare it to healthy age-matched controls. METHODS: Paediatric patients classified with BD according to the 2015 international paediatric BD criteria in our centre were included in the study. Intima-media thickness of the lower extremity veins to evaluate VWT was measured by ultrasonography, including common femoral vein (CFV), femoral vein (FV), vena saphena magna, vena saphena parva and popliteal vein (PV). RESULTS: In this cross-sectional study, VWT was measured in 35 patients (63% male) and 27 healthy controls (55% male). Thirteen (37%) of 35 patients met the criteria for the diagnosis of BD. The remaining 22 (63%) had incomplete BD and met two criteria. The median VWT values of both definite and incomplete BD patients were significantly higher than the control group in all veins on both sides. Regarding the best cut-off values of VWT for all lower extremity veins, the sensitivity rates were between 63% and 86%, while specificity rates were between 71% and 100%. CONCLUSION: Increased VWT was present not only in BD patients with vascular involvement but also in those without. We suggest that VWT may be a new criterion in supporting the diagnosis of childhood BD both in definite and incomplete BD patients.

Are the thickness and ADC values reliable to evaluate pancreas in children? A retrospective MRI study.

PURPOSE: To define the pancreatic thickness on the transverse plane and apparent diffusion coefficient (ADC) values at multiple anatomical locations in the normal pancreas of children and to evaluate inter-rater and intra-rater reliability. METHODS: Two reviewers measured the thickness and ADC values of the pancreas at four locations obtained from two different 1,5 Tesla MRI scanners [MAGNETOM Symphony (Siemens Medical Systems, Erlangen, Germany) and Signa HDxt(GE Healthcare, Milwaukee, WI, USA)]. Measurements were made based on 190 retrospective MRI examinations. Patients were distributed among ten age groups for thickness measurements and three age groups for ADC measurements between 0 and 18 years. RESULTS: The thickness measurements from each segment of the pancreas were significantly correlated with patient age, height and weight (p < 0.01). Inter-rater agreement was excellent for pancreatic head (intraclass correlation coefficient (ICC): 0.837) and good for pancreatic neck, body and tail (ICC: 0.646, 0.632 and 0.678, respectively). We also defined the mean ADC values for three age groups. There was significant difference in the mean ADC value of the head and body by both the vendor and age group (p < 0.05). The mean ADC values and mean ranks of the Signa HDxt were significantly higher and the frequencies were lower than those of the MAGNETOM Symphony at all locations (p < 0.001). CONCLUSION: The thickness of the pancreatic head is more reliable than that at other locations. Pancreatic body and tail measurements are not as reliable as head or neck measurements due to discrepancies between published studies and low interobserver agreement. ADC values of the normal pancreas can be significantly different among vendors; therefore, ADC comparison on follow-up should be performed using same MRI machine.

Favourable outcomes of conservatively managed acute abdomen associated with multisystem inflammatory syndrome in children during the COVID-19 pandemic.

BACKGROUNDS: Abdominal pain is one of the most common symptoms of multisystem inflammatory syndrome in children (MIS-C). Abdominal pain can vary from mild to severe and may present as acute abdomen. Severe abdominal pain in patients with MIS-C should be differentiated from surgical causes of acute abdomen to prevent unnecessary surgery. METHODS: The diagnosis of MIS-C was based on WHO and CDC recommended criteria. Records of children treated for MIS-C between September 2020 and January 2021 were reviewed retrospectively. RESULTS: In a short time, we encountered seven patients who were diagnosed with MIS-C and showed acute abdomen findings. There were four male and three female patients. The median age was 9 years. Fever, abdominal pain and distension were present in all. The median duration of symptoms was 4 days. Five patients had general abdominal tenderness mimicking acute abdomen. Three patients had right lower quadrant tenderness mimicking acute appendicitis. After the initiation of immunomodulatory therapy and antibiotics, the physical examination findings were improved step by step in all. The median time to initiate oral feeding was 2 days. The median length of hospitalization time was 8 days. CONCLUSION: Serial abdominal examinations performed by the same surgeon enabled us to follow these patients conservatively and thus avoid unnecessary surgical intervention.

Small Cell Carcinoma of Ovary, Hypercalcemic Type: A Rare Case Report.

BACKGROUND: Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT), is a rare neoplasm that occurs mostly in women younger than 40 years of age. The unknown histogenesis makes the diagnosis of SCCOHT difficult. SCCOHT was recently shown to be associated with SMARCA4 gene mutation. Serum calcium levels can be used as a marker of treatment response and relapse in SCCOHT. CASE REPORT: Here we report on a 16-year-old girl who presented with pelvic mass and hypercalcemia. SCCOHT was diagnosed histopathologically. However, loss of neither BRG1 nor INI1 expression was detected. SUMMARY AND CONCLUSION: The diagnosis of SCCOHT should be among the differential diagnoses in adolescents presenting with pelvic mass and hypercalcemia. We would like to share our experience with this rare case, discuss recent management, and emphasize the importance of a multidisciplinary approach. Although it is known that almost all cases have a loss of BRG1 expression and a small group exhibit loss of INI1, our patient indicates that there could be exceptional cases with hitherto undescribed genetic abnormalities.

Giant cell tumor arising from the anterior arc of the rib: an extremely rare site in an adolescent girl.

BACKGROUND: Giant cell tumor is a rare and locally aggressive neoplasm of the long bones in children. Rib is the least frequently affected site, seen in less than 1% of all cases and most of them occur at the posterior arc. CASE: A 12-year-old girl presented with swelling and slight pain on the left inferior-anterior chest wall for two years. Physical examination revealed a giant, hard and fixed mass on the left chest wall. Hematological and biochemical test results were in normal limits but slight elevation of alkaline phosphatase level. Computed tomography of the chest showed a large expansive mass and lytic lesion with internal calcification arising from the anterior part of the 7th rib. En-bloc resection was performed including the 6th-8th ribs and a small part of the diaphragm. The pathological evaluation revealed giant cell tumor of bone. CONCLUSIONS: Herein, we aim to emphasize that giant cell tumor should be considered in the differential diagnosis of chest wall tumors in childhood whereby en-bloc resection and close follow up would be paramount.

A child presenting with bullous emphysema.

BACKGROUND: Placental transmogrification of the lung (PTL) is a clinical spectrum varying from asymptomatic to severe pulmonary impairment; such as recurrent pneumothorax, bronchopneumonia, respiratory distress syndrome and chronic obstructive airway disease. PTL usually presents as a bullous lesion, and rarely can appear in nodule or cyst formation on chest imaging. PTL with giant bullous emphysema has a male preference, is more commonly unilateral and mostly affects one lobe, but can rarely involve more than one lobe. CASE: Here we report a 13-year-old boy presenting with bullous emphysema and coexisting with a borderline testicular tumor. He had no complaints of cough, sputum, or shortness of breath. He had a past medical history of pneumonia five years ago. In order to elucidate the underlying lung pathology, a wedge lung biopsy was performed and the patient was diagnosed with PTL. Scrotum ultrasonography was performed because of hydrocele in both testes, and bilateral epididymal cysts with papillary solid projections were reported. Pathological examination of the epididymal tumor revealed a `Mullerian type borderline epithelial neoplasm` which is an analogue of the ovarian serous borderline tumor. CONCLUSIONS: In conclusion, we reported the youngest PTL case in the literature, a rare disease with unknown pathophysiology, presenting as bullous emphysema and coincidental Mullerian type borderline epithelial neoplasm. It is important to diagnose placental transmogrification of the lung in a child with bullous emphysema because compared to other cystic lung diseases it is a benign disease and if no additional malignity exists, lobectomy or pneumonectomy is the cure for the disease.

Clinical radiological and pathological staging of children with hypersensitivity pneumonitis.

OBJECTIVE: Hypersensitivity pneumonitis (HP) is rare in the pediatric population. To date, there are no studies defining a correlation between clinical, radiological, and pathological findings in children with HP. The objective of this study is to define the clinical, and radiological characteristics and prognosis of childhood HP and to examine the clinical, radiological, and pathological correlation between HP stages. METHODS: Patients with suspected HP and followed at two tertiary care hospitals between 2000 and 2020 were retrospectively evaluated. Computed tomography (CT) of the chest of patients was evaluated by a single radiologist. The interagreement between clinical and radiological severity of the patients was calculated with the κ test. RESULTS: Fourteen children with suspected HP were identified. The results of 10 patients with the definitive diagnosis were as follows: one patient (10%) had acute, five patients (50%) had subacute, and four patients (40%) had chronic HP. The most prominent findings in chest CT were hilar, or hilar and subcarinal lymphadenopathy (80%), centrilobular nodules (60%), patchy or diffuse ground-glass opacities (50%), and cysts (50%). The interagreement between clinical and radiological severity of the patients was 100% (approximate significance: 0.003). The diagnosis of four patients with suspected HP who were unresponsive to standardized medical treatments or developed multisystem involvement was diagnosed with other diseases. One patient (10%) with definitive chronic HP died due to respiratory failure during follow up. CONCLUSION: Similar to adult HP, the prognosis is worse in children with existing fibrotic equivalents in chest CT. Patients who are not responding to standard medical treatments or develop multisystem involvement should be evaluated for other lung diseases.

Beyond Wilms tumor: imaging findings and outcomes of rare renal tumors in children.

BACKGROUND: Compared to Wilms, non-Wilms renal tumors in children are less well understood due to their rare occurrence which limits precise definition of the typical imaging patterns. OBJECTIVE: This study aims to identify distinctive imaging findings, demographic characteristics and prognosis of pediatric non-Wilms renal tumors. MATERIALS AND METHODS: From January 2007 to December 2018, 207 patients with a diagnosis of primary kidney neoplasia were yielded from our radiology archive, 171 of whom were diagnosed with Wilms tumor, 4 with angiomyolipoma and one with nephrogenic rest. The remaining 31 patients with a diagnosis of primary kidney neoplasia were enrolled in this retrospective study. Imaging data, age, gender, prognosis and findings regarding follow-up were noted. RESULTS: Eight patients had renal cell carcinoma, seven had clear cell sarcoma, six had mesoblastic nephroma, four had rhabdoid tumor, three had desmoplastic small round cell tumor, two had cystic nephroma and one had metanephric stromal tumor. The age of diagnosis was > 8 years for renal cell carcinoma and desmoplastic small round cell tumor, < 5 years for rhabdoid tumor and < 7 months for mesoblastic nephroma. There was no gender preference for any tumor type. The prognosis for rhabdoid tumor was extremely poor in that all the patients followed up in our institute were deceased, whereas no recurrence was found in other tumors. Translocation type renal cell carcinoma had lower T2-weighted signal intensity, mesoblastic nephroma was a predominantly cystic mass, clear cell sarcoma was generally larger at presentation and extensive amorphous calcifications were seen in desmoplastic small round cell tumor. CONCLUSION: For the differential diagnosis of pediatric non-Wilms renal tumors, age is the most important factor, followed by propensity to metastasize/aggressive behavior of the mass. Knowledge of specific imaging findings of these tumors may help to narrow the differential diagnosis.

Many faces of torsion in pediatric female pelvis.

Pediatric patients of various ages, from infancy through adolescence, can have ovarian torsion. Torsion may not only be confined to the ovaries but may also involve the isolated cyst, tube, and even the uterus. In this pictorial review, we review the spectrum of torsion in pediatric (from infants to adolescents) female pelvis, emphasizing imaging methods.