ACR-SPR-STR Practice Parameter for the Performance of Cardiac Positron Emission Tomography - Computed Tomography (PET/CT) Imaging.

This clinical practice parameter has been developed collaboratively by the American College of Radiology (ACR), the Society for Pediatric Radiology (SPR), and the Society of Thoracic Radiology (STR). This document is intended to act as a guide for physicians performing and interpreting positron emission tomography-computed tomography (PET/CT) of cardiac diseases in adults and children. The primary value of cardiac PET/CT imaging include evaluation of perfusion, function, viability, inflammation, anatomy, and risk stratification for cardiac-related events such as myocardial infarction and death. Optimum utility of cardiac PET/CT is achieved when images are interpreted in conjunction with clinical information and laboratory data. Measurement of myocardial blood flow, coronary flow reserve and detection of balanced ischemia are significant advantages of cardiac PET perfusion studies. Increasingly cardiac PET/CT is used in diagnosis and treatment response assessment for cardiac sarcoidosis.

Prevalence of non-cardiovascular findings on CT angiography in children with congenital heart disease.

BACKGROUND: CT angiography is gaining broader acceptance in the evaluation of children with known or suspected congenital heart disease. These studies include non-cardiovascular structures such as the mediastinum, lung parenchyma and upper abdominal organs. It is important to inspect all these structures for potential abnormalities that might be clinically important and, in some cases, may impact care plans. OBJECTIVE: To determine the prevalence of non-cardiovascular findings in CT angiography of children with congenital heart disease. MATERIALS AND METHODS: During 28 months, 300 consecutive children (170 males; mean age: 7.1 years, age range: 6 h-26 years), referred from a tertiary pediatric cardiology center, underwent clinically indicated CT angiography to evaluate known or suspected congenital heart disease. Slightly more than half (n = 169) of the patients were postoperative or post-intervention. Examinations were retrospectively reviewed, and non-cardiovascular findings were recorded and tabulated by organ system, congenital heart disease and operative procedure in conjunction with outcomes from medical charts. RESULTS: Non-cardiovascular findings were identified in 83% (n = 250 / 300) of the studies for a total of 857 findings. In 221 patients (n = 73.7% of 300) a total of 813 non-cardiovascular findings were clinically significant, while in 9.7% (n = 29 / 300) of patients, 5.1% (n = 44 / 857) of the findings were nonsignificant. In 38.3% (n = 115 / 300) of patients with significant non-cardiovascular pathology, the findings were unexpected and directly impacted patient care plans. Commonly involved organs with non-cardiovascular findings were the lungs with 280 non-cardiovascular findings in 176 / 300 (58.7%) of patients, the airway with 139 non-cardiovascular findings in 103 / 300 (34.3%) of patients and the liver with 108 non-cardiovascular findings in 72 / 300 (24.0%) of patients. Syndromic associations were noted in 22% (n = 66 / 300) of the patients. CONCLUSION: Non-cardiovascular findings are common in children with congenital heart disease who undergo CT angiography. Based upon our study population, if a child with congenital heart disease has a CT angiography, five out of six will have non-cardiovascular findings, while nearly three out of four (73.7%; 221 / 300) will have significant non-cardiovascular findings. Close attention to the non-cardiovascular structures in children with congenital heart disease presenting for a CT angiography is recommended as in nearly 40% of these children, findings were unexpected and directly altered patient care.

Vascular lesions--congenital, acquired, and iatrogenic: imaging in the neonate.

The imaging of vasculitis, vasculopathies, and other vascular disorders in neonates presents unique challenges compared with the vascular imaging of older children or adults. These challenges include small-caliber vessels, the need for sedation or anesthesia, a high rate of vasospasm, higher respiratory rates, and a greater susceptibility to long-term effects of ionizing radiation. Duplex ultrasound (US) is typically the first-line imaging modality; in most cases, US provides key diagnostic information necessary for guiding initial management. Magnetic resonance or computed tomography angiography may be performed following US to further define vascular anatomy and relationships, to achieve a definitive diagnosis, and to guide endovascular or surgical planning when necessary. This review article presents and illustrates an update on the imaging strategies for congenital, acquired, and iatrogenic vasculopathies and vascular disorders in neonates.

Cumulative exposure to medical radiation for children requiring surgery for congenital heart disease.

OBJECTIVE: To describe cumulative radiation exposure in a large single-center cohort of children with congenital heart disease (CHD) and identify risk factors for greater exposure. STUDY DESIGN: A detailed medical radiation exposure history was collected retrospectively for patients aged <18 years who underwent surgery for CHD between January 1, 2001, and July 22, 2009. Cumulative per patient exposure was quantified as the effective dose in millisieverts (mSv) and annualized (mSv/year). RESULTS: A total of 4132 patients were subjected to 134,715 radiation examinations at a median follow-up of 4.3 years (range, 0-8.6 years). Exposure clustered around the time of surgery. The median exposure was 14 radiologic tests (the majority of which were plain film radiographs) at an effective dose of 0.96 mSv (the majority of which was from cardiac catheterization), although this distribution had a very wide range. Almost three-quarters (73.7%) were exposed to <3 mSv/year, and 5.3% were exposed to >20 mSv/year. Neonates, children with genetic syndromes, and children requiring surgery for cardiomyopathy, pulmonary valve, single ventricle, or tricuspid valve diseases were more likely to have higher exposure levels, and those requiring surgery for aortic arch anomalies or atrioventricular septal defects were more likely to have lower levels. CONCLUSION: Children with CHD requiring surgery are exposed to numerous medical forms of ionizing radiation. Although the majority of patients receive <3 mSv/year, there are identifiable risk factors for higher exposure levels. This may have important health implications as these patients age.

Associations between routine coronary computed tomographic angiography and reduced unnecessary hospital admissions, length of stay, recidivism rates, and invasive coronary angiography in the emergency department triage of chest pain.

OBJECTIVES: This study was designed to assess the effects on resource utilization of routine coronary computed tomographic angiography (CCTA) in triaging chest pain patients in the emergency department (ED). BACKGROUND: The routine use of CCTA for ED evaluation of chest pain is feasible and safe. METHODS: We conducted a retrospective multivariate analysis of data from two risk-matched cohorts of 894 ED patients presenting with chest pain to assess the impact of CCTA versus standard evaluation on admissions rate, length of stay, major adverse cardiovascular event rates, recidivism rates, and downstream resource utilization. RESULTS: The overall admission rate was lower with CCTA (14% vs. 40%; p < 0.001). Standard evaluation was associated with a 5.5-fold greater risk for admission (odds ratio [OR]: 5.53; p < 0.001). Expected ED length of stay with standard evaluation was about 1.6 times longer (OR: 1.55; p < 0.001). There were no differences in the rates of death and acute myocardial infarction within 30 days of the index visit between the two groups. The likelihood of returning to the ED within 30 days for recurrent chest pain was 5 times greater with standard evaluation (OR: 5.06; p = 0.022). Standard evaluation was associated with a 7-fold greater likelihood of invasive coronary angiography without revascularization (OR: 7.17; p < 0.001), while neither group was significantly more likely to receive revascularization (OR: 2.06; p = 0.193). The median radiation dose with CCTA was 5.88 mSv (n = 1039; confidence interval: 5.2 to 6.4). CONCLUSIONS: The routine use of CCTA in ED evaluation of chest pain reduces healthcare resource utilization.

The role of CT angiography in the evaluation of pediatric renovascular hypertension.

Historically, the evaluation of renovascular hypertension has been accomplished by US, renal scintigraphy and digital subtraction angiography. Based on its high accuracy reported in adults renal CT angiography (CTA) with pediatric-appropriate low radiation dose techniques has become an important tool in the workup of renovascular hypertension in children. Renal CTA has several advantages over more conventional imaging modalities, including rapid and non-invasive acquisition, high resolution and easy reproducibility. Additionally, in our experience high-quality renal CTA can be performed using low-dose radiation exposures and can be acquired without sedation in most instances. This article illustrates by examples the usefulness of renal CTA for diagnosis of childhood renovascular hypertension and provides an overview of renal CTA findings in the most common childhood renovascular diseases.

Impact of clinical history on chest radiograph interpretation.

BACKGROUND: The inclusion of clinical information may have unrecognized influence in the interpretation of diagnostic testing. OBJECTIVE: The objective of the study was to determine the impact of clinical history on chest radiograph interpretation in the diagnosis of pneumonia. DESIGN: Prospective case-based study. METHODS: Radiologists interpreted 110 radiographs of children evaluated for suspicion of pneumonia. Clinical information was withheld during the first interpretation. After 6 months the radiographs were reviewed with clinical information. Radiologists reported on pneumonia indicators described by the World Health Organization (ie, any infiltrate, alveolar infiltrate, interstitial infiltrate, air bronchograms, hilar adenopathy, pleural effusion). SETTING: Children's Hospital of Philadelphia and Boston Children's Hospital. PARTICIPANTS: Six board-certified radiologists. OUTCOME MEASURES: Inter- and inter-rater reliability were assessed using the kappa statistic. RESULTS: The addition of clinical history did not have a substantial impact on the inter-rater reliability in the identification of any infiltrate, alveolar infiltrate, interstitial infiltrate, pleural effusion, or hilar adenopathy. Inter-rater reliability in the identification of air bronchograms improved from fair (k = 0.32) to moderate (k = 0.53). Intra-rater reliability for the identification of alveolar infiltrate remained substantial to almost perfect for all 6 raters with and without clinical information. One rater had a decrease in inter-rater reliability from almost perfect (k = 1.0) to fair (k = 0.21) in the identification of interstitial infiltrate with the addition of clinical history. CONCLUSIONS: Alveolar infiltrate and pleural effusion are findings with high intra- and inter-rater reliability in the diagnosis of bacterial pneumonia. The addition of clinical information did not have a substantial impact on the reliability of these findings.

Advances in uroradiologic imaging in children.

Diagnostic imaging of pediatric urologic disorders is continuously changing as technologic advances are made. Although the backbone of pediatric urologic imaging has been ultrasound, voiding cystourethrography, and radionuclide scintigraphy, newer and advanced modalities are becoming increasingly important. This article discusses the techniques and clinical applications of three such imaging modalities as they pertain to pediatric urologic disorders: (1) MR urography; (2) advanced ultrasound (harmonic imaging, three-dimensional, and voiding urosonography); and (3) CT angiography.

Squamosal suture synostosis: a cause of atypical skull asymmetry.

BACKGROUND: The squamosal suture is markedly different from the major calvarial sutures of the human skull. The unique properties of the suture are a result of the complex developmental biology of the temporal bone and biomechanical force exerted by surrounding structures. The dysmorphic effects of premature fusion of the suture, and possible treatment strategies in cases of synostosis, have received only brief description in the literature. METHODS: A retrospective case series was performed. The study included patients evaluated by one of the senior authors (S.P.B., R.R.R., and D.J.S.) between 1993 and 2009. All pertinent patient data including inpatient and outpatient charts, photographic records, and radiographic scans were reviewed. Any management performed under the direction of a craniofacial surgeon was documented--including orthotic helmet therapy and operative management. RESULTS: The study included 14 patients. Synostosis of the squamosal suture was noted to occur either in an isolated fashion or in the setting of other craniofacial malformations. Patients with isolated squamosal synostosis often suffered from a deformity that was mild in severity and tended to improve with time. However, when occurring in the setting of other forms of craniosynostosis, the deformity was often progressive, and transcranial surgery was frequently required. CONCLUSIONS: Synostosis of the squamosal suture can result in, or contribute to, significant craniofacial dysmorphism. The optimal form of therapy for this disorder is evolving.

Variability in the interpretation of chest radiographs for the diagnosis of pneumonia in children.

BACKGROUND: Although chest radiography is commonly used to establish the diagnosis of pneumonia in children, the reliability of radiographic findings among radiologists is not well described. OBJECTIVE: We sought to evaluate the inter-rater and intra-rater reliability of radiographic features commonly described by radiologists in childhood pneumonia. METHODS: Prospective case-based study. One hundred and ten radiographs of children evaluated in a pediatric emergency department for suspicion of pneumonia were interpreted by six radiologists at two academic children's hospitals. Radiologists were blinded to the clinical history. Reliability of standardized radiographic features was evaluated using the kappa statistic. RESULTS: The radiographic finding of an alveolar infiltrate demonstrated substantial reliability among radiologists (κ = 0.69). The presence of 'any infiltrate' and pleural effusion demonstrated moderate reliability (κ = 0.47 and k=0.45, respectively). Other radiographic features were less reliable: air bronchograms (κ = 0.32), hilar adenopathy (κ = 0.21), and interstitial infiltrate (κ = 0.14). Similarly, the finding of alveolar infiltrate demonstrated substantial intra-rater reliability upon review of ten duplicate radiographs, whereas interstitial infiltrate was less reliable. CONCLUSION: The radiographic finding of an alveolar infiltrate is very reliable among pediatric radiologists, whereas the finding of an interstitial infiltrate is less reliable.

Congenital thoracic vascular anomalies: evaluation with state-of-the-art MR imaging and MDCT.

Congenital thoracic vascular anomalies include embryologic developmental disorders of the thoracic aorta, aortic arch branch arteries, pulmonary arteries, thoracic systemic veins, and pulmonary veins. Diagnostic evaluation of these anomalies in pediatric patients has evolved with innovations in diagnostic imaging technology. State-of-the-art magnetic resonance (MR) imaging, MR angiography multidetector-row computed tomographic (MDCT) angiography, and advanced postprocessing visualization techniques offer accurate and reliable high-resolution two-dimensional and three-dimensional noninvasive anatomic displays for interpretation and clinical management of congenital thoracic vascular anomalies. This article reviews vascular MR imaging, MR angiography, MDCT angiography, and advanced visualization techniques and applications for the assessment of congenital thoracic vascular anomalies, emphasizing clinical embryology and the characteristic imaging findings.

Upper extremity computed tomographic angiography: state of the art technique and applications in 2010.

From technical and interpretative perspectives, upper extremity computed tomographic angiography (CTA) is one of the more challenging vascular CTA applications. Synchronizing the relatively large scan coverage with a single bolus of contrast medium requires precise selection of acquisition and contrast delivery parameters. To avoid multiple acquisitions and minimize radiation exposure and contrast medium volume, it is important to have fundamental knowledge on how to select these parameters. Equally important is knowing how to adeptly apply advanced workstation visualization techniques and tool functions for the upper extremity vascular tree. In this review, upper extremity arterial and venous anatomy is discussed, followed by a detailed overview on state-of-the-art upper extremity CTA technical considerations and strategies. The review concludes with discussion and illustration of upper extremity CTA clinical applications.

Pediatric computed tomographic angiography: imaging the cardiovascular system gently.

Whether congenital or acquired, timely recognition and management of disease is imperative, as hemodynamic alterations in blood flow, tissue perfusion, and cellular oxygenation can have profound effects on organ function, growth and development, and quality of life for the pediatric patient. Ensuring safe computed tomographic angiography (CTA) practice and "gentle" pediatric imaging requires the cardiovascular imager to have sound understanding of CTA advantages, limitations, and appropriate indications as well as strong working knowledge of acquisition principles and image post processing. From this vantage point, CTA can be used as a useful adjunct along with the other modalities. This article presents a summary of dose reduction CTA methodologies along with techniques the authors have employed in clinical practice to achieve low-dose and ultralow-dose exposure in pediatric CTA. CTA technical principles are discussed with an emphasis on the low-dose methodologies and safe contrast medium delivery strategies. Recommended parameters for currently available multidetector-row computed tomography scanners are summarized alongside recommended radiation and contrast medium parameters. In the second part of the article an overview of pediatric CTA clinical applications is presented, illustrating low-dose and ultra-low dose techniques, with an emphasis on the specific protocols.

Pediatric urologic advanced imaging: techniques and applications.

Diagnostic imaging of pediatric urologic disorders is continuously changing as technological advances are made. Although the backbone of pediatric urologic imaging has been ultrasound (US), voiding cystourethrography (VCUG), and radionuclide scintigraphy, newer and advanced modalities are increasingly becoming important. The aim of this review is to discuss the techniques and clinical applications of 3 such imaging modalities as they pertain to pediatric urologic disorders: MR urography, advanced US (harmonic imaging, 3D, voiding urosonography), and CT angiography.

Vascular involvement in tuberous sclerosis.

Vascular involvement in tuberous sclerosis (TS) is rare. Central and peripheral aneurysms and large and medium size arterial stenotic-occlusive disease have been reported in patients with TS. We present here three pediatric patients with TS and severe vascular abnormalities, followed by a review of the literature. The three cases include a 14-month-old girl with polycystic kidneys and cerebral tubers who had a large asymptomatic abdominal aortic aneurysm, a 2-year-old boy with multiple features of TS who had hypertension and was found to have mid-aortic syndrome with bilateral renal artery stenosis, and an 18-year-old girl with abdominal pain and TS features who had greater than 70% celiac artery stenosis. In all cases, noninvasive vascular imaging modalities were utilized for either initial diagnosis, surveillance, or both. These cases highlight the collaborative roles of the pediatric nephrologist and cardiovascular imager in the diagnosis and management of the vascular complications in TS patients. Appropriate care can only be made through a high index of suspicion.

Current imaging of prenatally diagnosed congenital lung lesions.

Congenital lung lesions refer to a spectrum of pulmonary developmental anomalies including, but not limited to, bronchial atresia, congenital pulmonary airway malformation (formerly known as congenital cystic adenomatoid malformation) and bronchopulmonary sequestration. These anomalies comprise about 90% of the anomalies seen in clinical practice. The advent of prenatal sonography and, more recently, fetal magnetic resonance imaging has changed our understanding and practice in the evaluation of congenital lung lesions. Postnatal imaging using low-dose computed tomography angiography (CTA) is extremely useful as it may provide information essential for differential diagnosis by allowing multiplanar reconstructions of the airway, lung parenchyma, and vasculature. The use of iodine in CTA permits the application of low-dose radiation protocols in these young patients. The purpose of this article is to emphasize the technical factors that may optimize low-dose CTA evaluation of these lesions. We also provide a description of prenatal imaging findings and helpful diagnostic clues that may be useful for the characterization of the most commonly encountered prenatally diagnosed pulmonary developmental anomalies.

Pediatric advanced imaging and informatics: state of the art.

Pediatric imaging has been at the forefront of radiology innovation since the days of Roentgen. In the past 2 decades, evolving computer technology and sophisticated software algorithms have rapidly advanced how pediatric radiologic examinations are acquired and displayed, interpreted and communicated, and stored and retrieved. Cost-effective use of this state of the art technology requires fundamental knowledge of the modalities, workstations, and informatics that guide advanced pediatric imaging in the current digital era. Equally important is an understanding of the advanced clinical applications and evidence supporting this use. In the first part of this review article, after a brief introduction and historical overview, technical principles are discussed. This is followed by a review of advanced clinical applications for fetal, cardiovascular, central nervous system, neck, thoracic, gastrointestinal, genitourinary, musculoskeletal, and virtual-autopsy imaging.

A case report of rapid progressive coarctation and severe middle aortic syndrome in an infant with Williams syndrome.

Williams syndrome is a genetic disorder caused by multiple contiguous gene deletions in chromosome 7. Presentation in early life is most often a result of luminal stenosis of right- and left-sided arterial vasculature. We report the case of a newborn infant who had a rapidly progressing diffuse form of arteriopathy that required two surgeries and one percutaneous balloon dilation within the first 2 months of her life.