US for Evaluation of Acute Abdominal Conditions in Neonates.

US is the imaging modality of choice for evaluation of a variety of abdominal conditions, and in recent years it has also become useful and promising as a bedside technique for assessment of acute abdominal conditions in neonates. Bedside US can help, complement, and sometimes replace radiographic or contrast-enhanced studies in critically ill and labile neonates who are difficult to transport to the fluoroscopy suite. Some of the features of bedside US can be applied as point-of-care US (POCUS) of the sick neonate. Some of the abdominal conditions in neonates that can be assessed and monitored with bedside US are necrotizing enterocolitis and its complications, malrotation with a midgut volvulus, segmental volvulus, meconium peritonitis, and complicated inguinal hernia. High-resolution US with the use of 15-MHz and higher-frequency probes allows characterization of the bowel anatomy and features of intestinal abnormalities in neonates in fine detail. Color Doppler US and microvascular imaging improve accuracy in the detection and characterization of bowel vascularity, which is important in the treatment and follow-up of patients with intestinal conditions. © RSNA, 2023 Quiz questions for this article are available through the Online Learning Center. The slide presentation from the RSNA Annual Meeting is available for this article.

Bone age for chronological age determination - statement of the European Society of Paediatric Radiology musculoskeletal task force group.

Radiologists are sometimes requested to determine a person's age based on skeletal radiographs. Critical reviews demonstrate that this cannot be done with sufficient accuracy with existing methods.

Less common manifestations in TSC.

Tuberous sclerosis complex (TSC) is due to pathogenic variants in TSC1 or TSC2 genes resulting in hyperactivation of the mTOR pathway. Many organ systems can be affected, such as brain, skin, eye, heart, bone, kidney, or lung. Typical lesions of TSC usually are those included as major criteria, including angiofibromas, hypomelanotic macules, tubers, subependymal nodules, angiomyolipomas, cardiac rhabdomyomas, and lymphangioleiomyomatosis. However, there are many other manifestations less frequent and/or less well known, many of them not included as clinical diagnostic criteria that are part of the clinical spectrum of TSC. The focus of this review will be on these less common and less well-known manifestations of TSC. Among the rare manifestations, we will discuss some clinical findings including arteriopathy, arachnoid cysts, lymphatic involvement, chordomas, gynecological, endocrine, and gastrointestinal findings. Among the manifestations that are very frequent but much less well known, we find the sclerotic bone lesions. Although they are very frequent in TSC they have been largely overlooked and not considered diagnostic criteria, mainly because they are asymptomatic. However, it is important to know their typical characteristics to avoid misdiagnosing them as metastasis.

Sclerotic bone lesions in tuberous sclerosis complex: A genotype-phenotype study.

Tuberous sclerosis complex (TSC) is due to pathogenic variants in TSC1 or TSC2 genes resulting in hyperactivation of the mTOR pathway. Many organ systems can be affected, such as brain, skin, eye, heart, bone, kidney, or lung. Sclerotic bone lesions have been reported as frequent findings in TSC although they are not considered diagnostic criteria. The objective of this study is to characterize sclerotic bone lesions detected by chest CT in a large cohort of adult TSC patients and to correlate with genotype. Chest CT scans of 92 adult patients with a definite clinical diagnosis of TSC were reviewed. Sclerotic bone lesions were found in 82 cases (89%) and affected mainly the posterior vertebral elements. Patients without bone lesions had negative mutational studies of TSC1/TSC2 in 86%. Awareness of these lesions in TSC is important to avoid misdiagnosis with osteoblastic metastases.

Infant lower extremity long bone growth rates: comparison of contemporary with early 20th century data using mixed effect models.

OBJECTIVES: Modern reference standards for long bone growth are lacking for infants (≤1 year). This study develops a quantitative framework to characterize lower extremity bone shaft growth during infancy based on radiographic images, and compares it to data from the 1930s. METHODS: Femoral, tibial, and fibular shaft length measurements (diaphysis plus metaphysis) were collected retrospectively from 70 infants on initial and follow-up skeletal surveys performed for suspected abuse (7/2005-2/2013). These serial skeletal survey data (SSSD) were compared to the Denver Child Research Council data (DCRCD), a 1930's longitudinal dataset from 80 infants. Mixed effects regression models were developed to estimate growth trajectories from these data. Growth trajectories and short-term (≤2 months) growth rates were compared. RESULTS: Statistically distinct models described the contemporary (SSSD) and historic (DCRCD) datasets; however, there was substantial overlap (77-90%) between their confidence bands for the three measured bones. Based on developed models, the average long bone shafts of the DCRCD are shorter at birth than SSSD (femur: 77.0 vs. 82.3 mm; tibia: 64.4 vs. 68.2 mm; fibula: 61.0 vs. 64.4 mm), but the DCRCD long bone growth rates are faster than SSSD (femur: 0.21 vs. 0.17 mm/day; tibia: 0.16 vs. 0.14 mm/day; fibula: 0.15 vs. 0.14 mm/day). Short-term growth rates of these bones decreased with age. The effect of sexual dimorphism on long bone growth during infancy was non-significant. CONCLUSION: This study provides reference standards for long bone growth rates during the dynamic period of infancy that may aid clinical assessment, and also inform research studies of disorders associated with altered skeletal growth.

Accuracy of whole-body MRI in the assessment of splenic involvement in lymphoma.

BACKGROUND: Accurate evaluation of the spleen is an important component of staging lymphoma, because this may have prognostic and therapeutic implications. PURPOSE: To determine the diagnostic value of whole-body magnetic resonance imaging (MRI), including diffusion-weighted imaging (whole-body MRI-DWI) in the detection of splenic involvement in lymphoma. MATERIAL AND METHODS: This IRB approved, prospective multicenter study included a total of 107 patients with newly diagnosed, histologically proven lymphoma who underwent 1.5 T whole-body MRI-DWI and FDG-PET/CT. Whole-body MRI-DWI and FDG-PET/CT were independently evaluated by a radiologist and a nuclear medicine physician, in a blinded manner. Splenic involvement at MRI was defined as splenic index > 725 cm(3) or discrete nodules. At FDG-PET/CT splenic involvement was defined as splenic uptake greater than liver uptake or hypodense nodules at contrast-enhanced CT. FDG-PET/CT augmented with follow-up imaging after treatment was used as reference standard. RESULTS: Splenic involvement was detected with FDG-PET/CT in 21 patients, all demonstrating response to treatment. The sensitivity, specificity, positive predictive value, and negative predictive value of whole-body MRI-DWI for the detection of splenic involvement were 85.7 %, 96.5 %, 85.7%, and 96.5%, respectively. Three out of six discrepancies were related to suboptimal criterion of splenic size used with whole-body MRI-DWI versus the size-independent FDG uptake. CONCLUSION: Whole-body MRI-DWI is reasonably accurate in the detection of splenic lymphomatous involvement.

Sclerotic bone lesions at abdominal magnetic resonance imaging in children with tuberous sclerosis complex.

BACKGROUND: Sclerotic bone lesions are often seen on chest CT in adults with tuberous sclerosis complex. OBJECTIVE: To characterize bone lesions at abdominal MRI in children with tuberous sclerosis complex. MATERIALS AND METHODS: This retrospective review included 70 children with tuberous sclerosis complex who had undergone abdominal MRI for renal imaging. An additional longitudinal study was performed in 50 children who had had two or more MRI scans. Abdominal CT (eight children) and radiographs (three children) were reviewed and compared with MRI. RESULTS: A total of 173 sclerotic bone lesions were detected in 51/70 children (73%; 95% confidence interval: 0.61-0.82) chiefly affecting vertebral pedicles. New lesions appeared in 20 children and growth of previous sclerotic bone lesions was documented in 14 children. Sclerotic bone lesions were more frequent in girls and in children with more extensive renal involvement. CONCLUSION: Sclerotic bone lesions are commonly detected by abdominal MRI in children with tuberous sclerosis complex. They usually affect posterior vertebral elements and their number and size increase with age. As current recommendations for tuberous sclerosis complex surveillance include renal MR performed in childhood, recognition of these lesions is useful.

Trends and patterns in the use of computed tomography in children and young adults in Catalonia - results from the EPI-CT study.

BACKGROUND: Although there are undeniable diagnostic benefits of CT scanning, its increasing use in paediatric radiology has become a topic of concern regarding patient radioprotection. OBJECTIVE: To assess the rate of CT scanning in Catalonia, Spain, among patients younger than 21 years old at the scan time. MATERIALS AND METHODS: This is a sub-study of a larger international cohort study (EPI-CT, the International pediatric CT scan study). Data were retrieved from the radiological information systems (RIS) of eight hospitals in Catalonia since the implementation of digital registration (between 1991 and 2010) until 2013. RESULTS: The absolute number of CT scans annually increased 4.5% between 1991 and 2013, which was less accentuated when RIS was implemented in most hospitals. Because the population attending the hospitals also increased, however, the rate of scanned patients changed little (8.3 to 9.4 per 1,000 population). The proportions of patients with more than one CT and more than three CTs showed a 1.51- and 2.7-fold increase, respectively, over the 23 years. CONCLUSION: Gradual increases in numbers of examinations and scanned patients were observed in Catalonia, potentially explained by new CT scanning indications and increases in the availability of scanners, the number of scans per patient and the size of the attended population.

Femoral head bone viability after free vascularized fibular grafting for osteonecrosis: SPECT/CT study.

PURPOSE: To evaluate femoral head bone viability following free vascularized fibular grafting (FVFG) for osteonecrosis using SPECT/CT imaging. METHODS: Ten hips (9 patients) with osteonecrosis of the femoral head (ONFH) undergoing FVFG were prospectively enrolled. Four cases showed ARCO stage II, while six showed ARCO stage III. The mean age at surgery was 15.7 years (range, 13-22 years). Hip Harris Score (HHS) was measured pre- and post-operative. Bone scintigraphy with SPECT/CT was performed at 2 weeks and 6 months following surgery. RESULTS: Mean follow-up was 4.0 years (range, 2-5.9 years). Mean HHS increased from 37.2 to 92.3. SPECT/CT findings revealed a progressive increase of femoral head uptake in all cases, suggesting subchondral graft bone viability. No progressive deformation of the femoral head was evidenced in radiographic evaluation at final follow-up. CONCLUSIONS: This study demonstrates FVFG's capacity for revitalizing femoral head subchondral bone grafting in patients with ONFH, surgically treated following Urbaniak's technique. © 2015 Wiley Periodicals, Inc. Microsurgery 36:573-577, 2016.

Thyroid nodules on chest CT of patients with tuberous sclerosis complex.

A few cases of thyroid disease have been reported in tuberous sclerosis complex (TSC); however, studies on prevalence and characterization of lesions have not been done. Patients with TSC are routinely screened using chest CT for assessment of lung disease. Incidental thyroid findings on chest CT have been reported in large studies of the general population. The purpose of this study is to evaluate the frequency and type of thyroid anomalies in a cohort of TSC patients. We performed a retrospective review of 93 patients with a definite diagnosis of TSC, who had a chest CT. Images of the thyroid gland and final radiological report were reviewed. Reports of additional thyroid studies performed in some patients were also reviewed. Thyroid abnormalities were present in 19 of 93 (20.4%) patients. They consisted mainly of hypodense lesions categorized as nodules. Multiple nodules were found in 10 patients (52.6%). There was one papillary carcinoma. Thyroid gland lesions may be part of the clinical spectrum of TSC. They are usually asymptomatic. As some cases of thyroid carcinoma have been described in TSC, ultrasound exams are recommended, given that CT is not the gold standard technique for thyroid evaluation.

Rib and vertebral bone fibrous dysplasia in a child with tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder characterized by benign hamartomas in multiple organ systems, primarily the skin, brain, heart, kidneys, lungs, and eyes. The skeletal system is commonly affected in patients with TSC, but these bone lesions are generally asymptomatic and have not been well characterized. We present clinically significant bone growth in two ribs and vertebrae in an 8-year-old male patient with TSC and discuss the effects of mammalian target of rapamycin (mTOR) inhibitors as a possible treatment for these osseous abnormalities. This report suggests that skeletal lesions may hold more clinical significance than previously assumed and that further research should be directed toward understanding bone involvement in TSC.

The yield of high-detail radiographic skeletal surveys in suspected infant abuse.

BACKGROUND: Skeletal surveys are routinely performed in cases of suspected child abuse, but there are limited data regarding the yield of high-detail skeletal surveys in infants. OBJECTIVE: To determine the diagnostic yield of high-detail radiographic skeletal surveys in suspected infant abuse. MATERIAL AND METHODS: We reviewed the high-detail American College of Radiology standardized skeletal surveys performed for suspected abuse in 567 infants (median: 4.4 months, SD 3.47; range: 4 days-12 months) at a large urban children's hospital between 2005 and 2013. Skeletal survey images, radiology reports and medical records were reviewed. A skeletal survey was considered positive when it showed at least one unsuspected fracture. RESULTS: In 313 of 567 infants (55%), 1,029 definite fractures were found. Twenty-one percent (119/567) of the patients had a positive skeletal survey with a total of 789 (77%) unsuspected fractures. Long-bone fractures were the most common injuries, present in 145 children (26%). The skull was the site of fracture in 138 infants (24%); rib cage in 77 (14%), clavicle in 24 (4.2%) and uncommon fractures (including spine, scapula, hands and feet and pelvis) were noted in 26 infants (4.6%). Of the 425 infants with neuroimaging, 154 (36%) had intracranial injury. No significant correlation between positive skeletal survey and associated intracranial injury was found. Scapular fractures and complex skull fractures showed a statistically significant correlation with intracranial injury (P = 0.029, P = 0.007, respectively). CONCLUSION: Previously unsuspected fractures are noted on skeletal surveys in 20% of cases of suspected infant abuse. These data may be helpful in the design and optimization of global skeletal imaging in this vulnerable population.

Whole-body MRI for initial staging of paediatric lymphoma: prospective comparison to an FDG-PET/CT-based reference standard.

OBJECTIVE: To compare whole-body MRI, including diffusion-weighted imaging (whole-body MRI-DWI), with FDG-PET/CT for staging newly diagnosed paediatric lymphoma. METHODS: A total of 36 children with newly diagnosed lymphoma prospectively underwent both whole-body MRI-DWI and FDG-PET/CT. Whole-body MRI-DWI was successfully performed in 33 patients (mean age 13.9 years). Whole-body MRI-DWI was independently evaluated by two blinded observers. After consensus reading, an unblinded expert panel evaluated the discrepant findings between whole-body MRI-DWI and FDG-PET/CT and used bone marrow biopsy, other imaging data and clinical information to derive an FDG-PET/CT-based reference standard. RESULTS: Interobserver agreement of whole-body MRI-DWI was good [all nodal sites together (κ = 0.79); all extranodal sites together (κ = 0.69)]. There was very good agreement between the consensus whole-body MRI-DWI- and FDG-PET/CT-based reference standard for nodal (κ = 0.91) and extranodal (κ = 0.94) staging. The sensitivity and specificity of consensus whole-body MRI-DWI were 93 % and 98 % for nodal staging and 89 % and 100 % for extranodal staging, respectively. Following removal of MRI reader errors, the disease stage according to whole-body MRI-DWI agreed with the reference standard in 28 of 33 patients. CONCLUSIONS: Our results indicate that whole-body MRI-DWI is feasible for staging paediatric lymphoma and could potentially serve as a good radiation-free alternative to FDG-PET/CT. KEYPOINTS: • Accurate staging is important for treatment planning and assessing prognosis • Whole-body MRI-DWI could be a good radiation-free alternative to FDG-PET/CT • Interobserver agreement of whole-body MRI-DWI is good • Agreement between whole-body MRI and the FDG-PET/CT reference standard is good • Most discrepancies were caused by suboptimal accuracy of size measurements on MRI.

Imaging of skeletal injuries associated with abusive head trauma.

Skeletal injuries are commonly encountered in infants and young children with abusive head trauma. Although certain patterns of intracranial injury suggest abuse, none are diagnostic. Therefore demonstration of associated unsuspected skeletal injuries has important implications, particularly when highly specific fractures are present. Skull fractures are commonly associated with intracranial injury, but no fracture pattern is indicative of physical abuse. Other skeletal injuries including classic metaphyseal lesions and rib, spine and scapular fractures are strong predictors of abusive head trauma in infants with intracranial injury. It is mandatory to perform rigorous skeletal surveys in infants and young children with clinical and neuroimaging findings concerning for abusive head trauma.

Ischial apophyseal fracture in an abused infant.

We report a previously healthy 4-month-old who presented to the hospital with leg pain and swelling and no history of trauma. Radiographs demonstrated a comminuted left femur fracture. Given the concern for child abuse, skeletal survey was performed and revealed four vertebral compression deformities. Although abuse was suspected, the possibility of a lytic lesion associated with the femur fracture and multiple spinal abnormalities raised the possibility of an underlying process such as Langerhans cell histiocytosis. Subsequently 18F-NaF positron emission tomographic (PET) scintigraphy revealed increased tracer activity in the ischium, and MRI confirmed an ischial apophyseal fracture. Pelvic fractures, particularly ischial fractures, are extremely rare in the setting of child abuse. This case report describes the multimodality imaging findings of an ischial fracture in an abused infant.

An electronic tool for systematic reporting of fractures on skeletal surveys in suspected child abuse: prototype development and physician feedback.

OBJECTIVE: To describe a skeletal survey data entry and compilation tool and assess physician attitudes toward this reporting approach. BACKGROUND: Narrative skeletal survey reports are highly variable and prone to inconsistencies with potential adverse impact on patients. MATERIALS AND METHODS: The prototype skeletal survey data entry and compilation tool was developed and introduced into clinical practice at a large urban children's hospital. Pediatric radiologists and child protection team (CPT) pediatricians completed a survey of reporting preferences. Skeletal survey reports between March 1, 2013, and March 1, 2014, were reviewed to assess use of the tool. RESULTS: The survey response rate was 70% (14/20) for radiologists and 100% (4/4) for CPT pediatricians. Among responding radiologists, 54.5% (6/11) indicated that a skeletal survey data entry and compilation tool was helpful for skeletal surveys with >3 fractures; 80% (8/10) of responding radiologists indicated that tabulated data from prior skeletal survey was helpful when interpreting a follow-up skeletal survey with >3 fractures; 90.9% (10/11) of radiologists thought the tool improved report organization; 72.7% (8/11) thought it improved accuracy. Most radiologists (11/12, 91.7%) and 100% (4/4) of CPT clinicians preferred reports with both free text and a tabulated fracture list for testifying in court when >3 fractures were present. The tool was used in the reporting of 14/23 (61%) skeletal surveys with >3 fractures during a 1-year period. A case example using the application is presented. CONCLUSION: Most radiologists and CPT physicians at our center prefer skeletal survey reports with tabulated data and narrative description; 91.7% (11/12) of radiologists and all CPT clinicians prefer this approach for testifying in court when >3 fractures are present.

Evaluation of bone viability.

Bone scintigraphy is an excellent tool to assess bone viability. The functional information provided is crucial in several clinical settings, like the detection of avascular necrosis, septic embolism, frostbite lesions and osteonecrosis, and to evaluate the results of surgical treatment in cases of avascular necrosis. Mechanisms to obtain molecular images, as well as different kind of techniques, are detailed. Comparative and multimodality imaging to focus on any clinical problem and a review of the clinical indications reflect the multidisciplinary approach with close collaboration between orthopaedists, radiologists and nuclear medicine physicians. Finally, an effort has been made to list the most important points of imaging of bone viability in children.

Prevalence and relevance of pediatric spinal fractures in suspected child abuse.

BACKGROUND: Spinal fractures are uncommon manifestations of child abuse and elimination of the lateral views of the spine from the initial skeletal survey protocol has been recommended. OBJECTIVE: To establish the prevalence of spinal fractures detected on skeletal surveys performed for suspected child abuse and their association with intracranial injury (ICI). MATERIALS AND METHODS: The ACR standardized skeletal surveys and neuroimaging studies of 751 children (ages 0-4 years) were reviewed. A positive skeletal survey was defined as having one or more clinically unsuspected fractures. RESULTS: Fourteen children had a total of 22 definite spinal fractures. This constituted 1.9% (14/751) of the total cohort, and 9.7% (14/145) of children with a positive skeletal survey. Advanced imaging confirmed the fractures in 13 of the 14 children and demonstrated 12 additional spinal fractures. In five cases, spinal fractures were the only positive skeletal findings. In 71% (10/14) of the children, the spinal fractures were accompanied by ICI. Children with spinal fractures were at significantly greater risk for ICI than those without spinal injury (P < 0.05). CONCLUSION: Spinal fractures are not rare in children with positive skeletal surveys performed for suspected abuse and they may be the only indication of skeletal trauma. There is an association between spinal fractures and ICI.

Vascularized periosteal graft from the first metatarsal bone: a new technique to prevent collapse of osteonecrosis of the talus in children. A case report.

Several microsurgical techniques have been described for the treatment of osteonecrosis of the talus (ONT). Recently reported in children, vascularized periosteal grafts showed promising revascularizing properties. We report a novel technique using a pedicled periosteal graft from the first metatarsal bone to treat steroid-induced early Ficat-Arlet stage III ONT in an 11-year-old boy. The patient presented initial favorable clinical and radiological results which were maintained at 34 months during the last follow-up. Through this original technique, and basing on the powerful osteogenic and vasculogenic propreties of periosteal flaps, we could effectively induce bone revascularization and prevent further collapse of the talar dome.

Exploring the Potential of Three-Dimensional Imaging, Printing, and Modeling in Pediatric Surgical Oncology: A New Era of Precision Surgery.

Pediatric surgical oncology is a technically challenging field that relies on CT and MRI as the primary imaging tools for surgical planning. However, recent advances in 3D reconstructions, including Cinematic Rendering, Volume Rendering, 3D modeling, Virtual Reality, Augmented Reality, and 3D printing, are increasingly being used to plan complex cases bringing new insights into pediatric tumors to guide therapeutic decisions and prognosis in different pediatric surgical oncology areas and locations including thoracic, brain, urology, and abdominal surgery. Despite this, challenges to their adoption remain, especially in soft tissue-based specialties such as pediatric surgical oncology. This work explores the main innovative imaging reconstruction techniques, 3D modeling technologies (CAD, VR, AR), and 3D printing applications through the analysis of three real cases of the most common and surgically challenging pediatric tumors: abdominal neuroblastoma, thoracic inlet neuroblastoma, and a bilateral Wilms tumor candidate for nephron-sparing surgery. The results demonstrate that these new imaging and modeling techniques offer a promising alternative for planning complex pediatric oncological cases. A comprehensive analysis of the advantages and limitations of each technique has been carried out to assist in choosing the optimal approach.