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Objective: Parry-Romberg syndrome (PRS) and en coup de sabre (ECDS) are subtypes of craniofacial localized scleroderma. Systematic analyses of central nervous system imaging findings and their clinical associations in children are lacking. Here, we aim to characterize neuroimaging findings and associated neurological symptoms in these conditions. Methods: Neuroimaging and neurological symptoms of children evaluated at our institution with a diagnosis of PRS or ECDS were retrospectively reviewed. Laterality, location, stability, and number of lesion(s) were evaluated, as was the presence of susceptibility lesion(s) and contrast enhancement. History of seizures or headaches was noted. Results: From 2003 to 2019, 80 patients with PRS or ECDS were followed at our institution. Neuroimaging was completed in 73 and found to be abnormal in 25. In 12 (48%) of these 25 cases, headaches and/or seizures were present. In the vast majority of these cases (22/25, 88%), lesions were ipsilateral to skin findings. White matter was involved in 19 (76%) patients. MRI abnormalities preceded a rheumatological diagnosis in 7 (28%). Susceptibility lesions were noted in 11 (44%), and 8 (73%) of these patients endorsed a history of headaches. Most lesions were in the supratentorial compartment, did not enhance, and were stable at 1-year follow up imaging. Of those with progression, susceptibility findings were present at baseline. Conclusions: Neuroimaging findings in pediatric PRS and ECDS are often supratentorial, stable, unilateral, and ipsilateral to skin findings, and they can precede cutaneous findings.

We built 2 versions of an asynchronous pediatric orthopedic educational intervention for emergency medicine residents and sought to compare the two. We hypothesized that the version incorporating more instructional scaffolding in the form of a cognitive aid (CA) would optimize germane cognitive load for our target novice learners and result in higher test scores.Learners were block randomized to either a "CA" or "non-CA" arm, each containing a random set of 18 modules. The CA arm incorporated an orthopedic fracture classification chart embedded within the diagnostic questions to guide the learner in forming a diagnosis. The non-CA arm was designed with more active learning as the classification chart was provided only after each diagnostic answer submission. For both arms, the final 6 modules completed per learner were scored. Learners also completed a perceived cognitive load assessment tool measured on a 10-point Likert scale.Learners in the non-CA arm had a mean total score on the testing modules of 33% correct compared with a mean total score of 44% correct for learners in the CA arm (mean difference, 11; 95% confidence interval, 4%-19%, P = 0.005). There was a trend for the CA arm to have lower perceived overall cognitive load scores; however, this did not reach statistical significance.Emergency medicine residents performed better after completing the CA version of our educational intervention. Applying cognitive load theory to an educational intervention may increase its success among target learners.

Background: Children with ventricular shunts undergo frequent neuroimaging in the emergency department (ED) to evaluate for possible shunt malfunctions. Historically, the primary imaging modality has been computed tomography (CT), which exposes patients to ionizing radiation and an increase in the lifetime risk of malignancy. “Rapid” magnetic resonance imaging (rMRI) is an accurate and feasible alternative to CT for shunt evaluations. Therefore, we sought to reduce use of CT and increase use of rMRI as the primary neuroimaging study for the evaluation of suspected shunt malfunction. Specifically, we aimed to reduce the proportion of head CTs among …

Background Rapid magnetic resonance imaging (MRI) protocols may be effective in the emergency department (ED) to evaluate nontraumatic neurologic complaints. We evaluate neuroimaging (rapid MRI [rMRI]), head computerized tomography [HCT], and full MRI) use following widespread implementation of rMRI protocols in a pediatric emergency department (ED). Methods We conducted a retrospective study in a tertiary care pediatric ED of encounters with neuroimaging during two 9-month periods: one prior to (control period) and one after generalized availability of 4 rMRI protocols (rMRI period). The primary outcome was differences in neuroimaging rates between the two periods. Secondary outcomes included ED process measures, unsuccessful imaging, and undetected pathology, with full MRI within 14 days as the reference standard. Results There were 1052 encounters with neuroimaging during the control and 1308 during the rMRI periods. Differences in neuroimaging between periods were 27.7% for rMRI (95% CI, 24.4, 31.0), − 21.5% for HCT (95% CI, − 25.5, − 17.5), and − 6.2% for full MRI (95% CI, − 9.3, − 3.1%.) Time to imaging (182 [IQR 138–255] versus 86 [IQR 52–137] minutes) as well as ED length of stay (396 [IQR 304–484] versus 257 [IQR 196–334] minutes) was longer for rMRI versus HCT (p p p n = 2) and patient motion (n = 20). None of the rMRI studies with full MRI follow-up imaging had undetected pathology; the false negative rate for the HCT exams was as high as 25%. Conclusions After routine ED use of 4 rMRI protocols, there was a more than 20% decrease in HCT use without missed diagnoses. Time to neuroimaging and length of stay were longer for rMRI than HCT, with higher rates of unsuccessful imaging. Despite these limitations, rMRI may be an alternative to HCT for nontraumatic complaints in the ED.

Objectives Management of spontaneous pneumomediastinum in the pediatric population is highly variable. There are limited data on the use of diagnostic tests and the need for admission. Our objectives were to characterize the management of pediatric spontaneous pneumomediastinum, determine the diagnostic yield of advanced imaging, and describe the patients' outcomes. Methods This is a retrospective cohort study of all patients presenting to a single tertiary pediatric emergency department between January 2008 and February 2015 diagnosed with pneumomediastinum. Patients were identified using 2 complementary strategies: International Classification of Diseases, Ninth Revision billing codes and a keyword search of the hospital radiology database. Results We identified 183 patients with spontaneous pneumomediastinum. The mean age was 12.8 ± 4.8 years. Diagnosis was established by chest radiograph (CXR) in 165 (90%) patients, chest computed tomography in 15 (8%), neck imaging in 2 (1%), and abdominal imaging in 1. After diagnosis, many patients underwent additional studies: repeat CXR (99, 54%), chest computed tomography (53, 29%), esophagram (45, 25%), and laryngoscopy (15, 8%). Seventy-eight percent of patients (n = 142) were admitted with a median length of stay of 27 hours (18.4-45.6 hours). Six patients returned to the emergency department within 96 hours for persistent chest pain; 2 were admitted, and 1 was found to have worsening pneumomediastinum on CXR. We performed a secondary analysis on 3 key subgroups: primary spontaneous pneumomediastinum (64, 35%), secondary gastrointestinal-associated pneumomediastinum (31, 17%), and secondary respiratory-associated pneumomediastinum (88, 48%). No patients in the study received an invasive intervention for pneumomediastinum. In all patients, further studies did not yield additional diagnostic information. Conclusions Our data suggest that patients with spontaneous pneumomediastinum who are clinically well appearing can be managed conservatively with clinical observation, avoiding exposure to radiation and invasive procedures.

Supplemental Digital Content is available in the text., Introduction: Children with ventricular shunts undergo frequent neuroimaging, and therefore, radiation exposures, to evaluate shunt malfunctions. The objective of this study was to safely reduce radiation exposure in this population by reducing computed tomography (CT) and increasing “rapid” magnetic resonance imaging (rMRI-shunt) among patients warranting neuroimaging for possible shunt malfunction. Methods: This was a single-center quality improvement study in a tertiary care pediatric emergency department (ED). We implemented a multidisciplinary guideline for ED shunt evaluation, which promoted the use of rMRI-shunt over CT. We included patients younger than 18 years undergoing an ED shunt evaluation during 11 months of the preintervention and 25 months of the intervention study periods. The primary outcome was the CT rate, and we evaluated the relevant process and balancing measures. Results: There were 266 encounters preintervention and 488 during the intervention periods with similar neuroimaging rates (80.7% versus 81.5%, P = 0.8.) CT decreased from 90.1% to 34.8% (difference −55.3%, 95% confidence interval [CI]: −71.1, −25.8), and rMRI-shunt increased from 9.9% to 65.2% (difference 55.3%, 95% CI: 25.8, 71.1) during the preintervention and intervention periods, respectively. There were increases in the mean time to neuroimaging (53.1 min; [95% CI: 41.6, 64.6]) and ED length of stay (LOS) (52.3 min; [95% CI: 36.8, 67.6]), without changes in total neuroimaging, 72-hour revisits, or follow-up neuroimaging. Conclusions: Multidisciplinary implementation of a standardized guideline reduced CT and increased rMRI-shunt use in a pediatric ED setting. Clinicians should balance the reduction in radiation exposure with ED rMRI-shunt for patients with ventricular shunts against the increased time of obtaining imaging and LOS.

The potential benefits of peptide-based immunotherapy for pediatric brain tumors are under investigation. Treatment-related heterogeneity has resulted in radiographic challenges, including pseudoprogression. Conventional MR imaging has limitations in assessment of different forms of treatment-related heterogeneity, particularly regarding distinguishing true tumor progression from efficacious treatment responses. Advanced neuroimaging techniques, including diffusion magnetic resonance (MR), perfusion MR, and MR spectroscopy, may add value in the assessment of treatment-related heterogeneity. Observations suggest that recent delineation of specific response criteria for immunotherapy of adult brain tumors is likely relevant to the pediatric population and further validation in multicenter pediatric brain tumor peptide-based vaccine studies is warranted.

Head computed tomography (CT) is the current standard of care for evaluating infants at high risk of abusive head trauma. To both assess the feasibility of using a previously developed magnetic resonance imaging (MRI) brain injury screen (MRBRscreen) in the acute care setting in place of head CT to identify intracranial hemorrhage in high-risk infants and to compare the accuracy of a rapid imaging pulse sequence (single-shot T2 fast spin echo [ssT2FSE]) to a conventional pulse sequence (conventional T2 fast spin echo [conT2FSE]). This was a quality improvement initiative to evaluate infants

Objective The aim of this study was to assess the management and outcomes of healthy pediatric patients diagnosed radiologically with transient and benign small bowel-small bowel intussusception (SB-SBI). Methods Retrospective cohort study of healthy patients 0 to 18 years of age who presented to a children's hospital emergency department from January 1, 2005, to June 30, 2015, and had transient and benign SB-SBI characterized by spontaneous resolution (ie, transient), diameter of less than 2.5 cm, no lead point, normal bowel wall thickness, nondilated proximal small bowel, and no colonic involvement (ie, benign radiographic features). Charts were reviewed for demographics, clinical presentation, radiologic studies obtained, outcomes, and further management. Medical and radiologic records were also reviewed for 1 year after presentation for any subsequent pathologic diagnoses. Results Sixty-eight patients were included in our study, with a total of 87 episodes of transient and benign SB-SBI on initial or follow-up examination. Overall, 39 patients (57%) were admitted to the hospital, and 38 patients (56%) had a surgical consultation. Twenty-four patients (35%) had further radiologic studies obtained, including computed tomography scans, esophagogastroduodenoscopy, Meckel's scan, barium swallow studies, and magnetic resonance imaging. All studies were negative for concerning pathology including apparent lead points. None of the patients required surgical intervention or had any complications. Conclusions Transient and benign SB-SBIs with reassuring radiologic and clinical features diagnosed in healthy pediatric patients are likely incidentally found and are unlikely to be associated with a pathologic lead point.

Posterior reversible encephalopathy syndrome (PRES) is a clinical-radiological entity affecting both adults and children characterized by neurotoxicity often in setting of hypertension coupled with distinct brain magnetic resonance imaging features. Decreased serum albumin level has been suggested to correlate with the presence of vasogenic brain edema in adult PRES. Serum albumin has thus been hypothesized to protect against neurotoxicity in PRES by reducing vasogenic brain edema through its role in maintaining plasma osmotic pressure and endothelial integrity. The purpose of our study was to investigate if such correlation between decreased serum albumin level and PRES-related vasogenic edema could be found in children. We conducted a retrospective study of 25 pediatric patients diagnosed with PRES. Underlying clinical conditions, presenting symptoms, blood pressures, and serum albumin levels at onset of symptoms were collected. Brain MR imaging studies were reviewed. We used a quantitative method to evaluate the degree of vasogenic edema by measuring apparent diffusion coefficient (ADC) values of the T2-FLAIR hyperintense brain lesions. No significant correlation was found between serum albumin level and degree of PRES-related vasogenic edema. A significant correlation was found between elevated blood pressure and degree of vasogenic edema in the temporal lobes (p = 0.02 and 0.04, respectively) but not in the other cerebral lobes or cerebellum. Our initial results suggest blood pressure, not serum albumin level, as a main biomarker for brain edema in children with PRES. Thus, our study does not suggest a protective role of serum albumin against PRES-related neurotoxicity in children.

The potential benefits of peptide-based immunotherapy for pediatric brain tumors is currently under investigation with pilot studies at our institution. We have noted the presence of treatment-related heterogeneity, which has resulted in radiographic challenges including that of pseudoprogression. Conventional MRI has limitations in the assessment of these different forms of treatment-related heterogeneity, particularly in regards to distinguishing true tumor progression from efficacious treatment responses. Our initial results suggest that advanced neuroimaging techniques, including diffusion MR, perfusion MR and MR spectroscopy may add value in the assessment of treatment-related heterogeneity. Our initial observations suggests that recent delineation of specific response criteria for immunotherapy of adult brain tumors (iRANO) is likely to be relevant to the pediatric population and further validation in multi-center pediatric brain tumor peptide-based vaccine studies are warranted.

Primary CNS tumors consist of a diverse group of neoplasms originating from various cell types in the CNS. Brain tumors are the most common solid malignancy in children under the age of 15 years and the second leading cause of cancer death after leukemia. The most common brain neoplasms in children differ consistently from those in older age groups. Pediatric brain tumors demonstrate distinct patterns of occurrence and biologic behavior according to sex, age, and race. This chapter highlights the imaging features of the most common tumors that affect the child's CNS (brain and spinal cord).

Objectives To quantify the number of shunt-related imaging studies that patients with ventricular shunts undergo and to calculate the proportion of computed tomography (CT) scans associated with a surgical intervention. Study design Retrospective longitudinal cohort analysis of patients up to age 22 years with a shunt placed January 2002 through December 2003 at a pediatric hospital. Primary outcome was the number of head CT scans, shunt series radiograph, skull radiographs, nuclear medicine, and brain magnetic resonance imaging studies for 10 years following shunt placement. Secondary outcome was surgical interventions performed within 7 days of a head CT. Descriptive statistics were used for analysis. Results Patients (n = 130) followed over 10 years comprised the study cohort. The most common reasons for shunt placement were congenital hydrocephalus (30%), obstructive hydrocephalus (19%), and atraumatic hemorrhage (18%), and 97% of shunts were ventriculoperitoneal. Patients underwent a median of 8.5 head CTs, 3.0 shunt series radiographs, 1.0 skull radiographs, 0 nuclear medicine studies, and 1.0 brain magnetic resonance imaging scans over the 10 years following shunt placement. The frequency of head CT scans was greatest in the first year after shunt placement (median 2.0 CTs). Of 1411 head CTs in the cohort, 237 resulted in surgical intervention within 7 days (17%, 95% CI 15%-19%). Conclusions Children with ventricular shunts have been exposed to large numbers of imaging studies that deliver radiation and most do not result in a surgical procedure. This suggests a need to improve the process of evaluating for ventricular shunt malfunction and minimize radiation exposure.

PURPOSE The purpose of this study was to identify imaging markers and clinical risk factors that significantly predict the evolution of computed tomography (CT) imaging features of carotid artery atherosclerotic disease over a 1-year period. METHODS Our prospective study involved 120 consecutive patients undergoing emergent CT evaluation for symptoms of acute stroke. These patients were asked to consent to a follow-up CT exam in 1 year. To evaluate for atherosclerotic plaque, both at baseline and on follow-up, we employed a comprehensive computed tomography angiography (CTA) protocol that captured the carotid, vertebral, aortic, and coronary arteries. To further evaluate carotid artery plaque components, we used an automated classifier computer algorithm that distinguishes among the histological components of the carotid artery wall (lipids, calcium, fibrous tissue) based on appropriate thresholds of CT density. Baseline values of carotid imaging features and clinical variables were assessed for their ability to significantly predict changes in these imaging features over 1 year. RESULTS Of these 120 consecutive patients, 17 received both a baseline and a follow-up CTA exam. Wall volume increased more when the largest lipid cluster was located close to the lumen (coefficient −7.61, −13.83 to −1.40, P = .016). The volume of lipid increased with age (coefficient .36, .21 to .50, P = .000), in smokers (coefficient 8.89, 6.82 to 10.95, P = .000) and when fewer lipid clusters were present at baseline (coefficient −0.11, −0.17 to −.04, P = .001). The volume of calcium increased with greater volume of lipid at baseline (coefficient .35, .02 to .68, P = .035) and in patients on statins (coefficient 4.79, 1.73 to 7.86, P = .002). CONCLUSIONS There are a number of imaging markers and risk factors that significantly predict the evolution of CT imaging features of carotid artery atherosclerotic disease over a 1-year period.

For typically developing infants, the last trimester of fetal development extending into the first post-natal months is a period of rapid brain development. Infants who are born premature face significant risk of brain injury (e.g., intraventricular or germinal matrix hemorrhage and periventricular leukomalacia) from complications in the perinatal period and also potential long-term neurodevelopmental disabilities because these early injuries can interrupt normal brain maturation. Neuroimaging has played an important role in the diagnosis and management of the preterm infant. Both cranial US and conventional MRI techniques are useful in diagnostic and prognostic evaluation of preterm brain development and injury. Cranial US is highly sensitive for intraventricular hemorrhage (IVH) and provides prognostic information regarding cerebral palsy. Data are limited regarding the utility of MRI as a routine screening instrument for brain injury for all preterm infants. However, MRI might provide diagnostic or prognostic information regarding PVL and other types of preterm brain injury in the setting of specific clinical indications and risk factors. Further development of advanced MR techniques like volumetric MR imaging, diffusion tensor imaging, metabolic imaging (MR spectroscopy) and functional connectivity are necessary to provide additional insight into the molecular, cellular and systems processes that underlie brain development and outcome in the preterm infant. The adult concept of the "connectome" is also relevant in understanding brain networks that underlie the preterm brain. Knowledge of the preterm connectome will provide a framework for understanding preterm brain function and dysfunction, and potentially even a roadmap for brain plasticity. By combining conventional imaging techniques with more advanced techniques, neuroimaging findings will likely be used not only as diagnostic and prognostic tools, but also as biomarkers for long-term neurodevelopmental outcomes, instruments to assess the efficacy of neuroprotective agents and maneuvers in the NICU, and as screening instruments to appropriately select infants for longitudinal developmental interventions.

Background and Purpose— The purpose of this study was to determine whether significant atherosclerotic disease in the carotid arteries predicts significant atherosclerotic disease in the coronary arteries, vertebral arteries, or aorta in patients with symptoms of acute ischemic stroke. Methods— Atherosclerotic disease was imaged using CT angiography in a prospective study of 120 consecutive patients undergoing emergent CT evaluation for symptoms of stroke. Using a comprehensive CT angiography protocol that captured the carotid arteries, coronary arteries, vertebral arteries, and aorta, we evaluated these arteries for the presence and severity of atherosclerotic disease. Significant atherosclerotic disease was defined as >50% stenosis in the carotid, coronary, and vertebral arteries, or ≥4 mm thickness and encroaching in the aorta. Presence of any and significant atherosclerotic disease was compared in the different types of arteries assessed. Results— Of these 120 patients, 79 had CT angiography examinations of adequate image quality and were evaluated in this study. Of these 79 patients, 33 had significant atherosclerotic disease. In 26 of these 33 patients (79%), significant disease was isolated to 1 type of artery, most often to the coronary arteries (N=14; 54%). Nonsignificant atherosclerotic disease was more systemic and involved multiple arteries. Conclusions— Significant atherosclerotic disease in the carotid arteries does not predict significant atherosclerotic disease in the coronary arteries, vertebral arteries, or aorta in patients with symptoms of acute ischemic stroke. Significant atherosclerotic disease is most often isolated to 1 type of artery in these patients, whereas nonsignificant atherosclerotic disease tends to be more systemic.

BACKGROUND AND PURPOSE: PCT has emerged as an alternative to MR imaging for the assessment of patients with suspected acute stroke. However, 1 disadvantage of PCT is its limited anatomic coverage, which may impact the characterization of hemispheric ischemic strokes. The purpose of this study was to determine the optimal brain CT coverage required to accurately estimate the size of the infarct core relative to the MCA territory and the infarct-penumbra mismatch, by using a criterion standard of these parameters measured on PCT with 80-mm z-axis coverage. MATERIALS AND METHODS: Fifty-one patients with acute ischemic hemispheric stroke underwent PCT scanning (2 boluses, total coverage of 80 mm, 16 × 5 mm sections) within the first 24 hours of symptom onset and a follow-up NCCT of the brain between 3 days and 3 months after the initial stroke CT study. The volumes of PCT infarct and penumbra for each possible extent of z-axis coverage derived from the individual PCT sections were recorded (beginning with 5 mm of z-axis coverage above the orbits and then increasing the coverage in 5-mm increments in the z-axis up to 80 mm above the orbits). The infarct-penumbra mismatch and the size of the infarction relative to the MCA territory were calculated for each extent of z-axis coverage. Using the 80-mm z-axis coverage as the criterion standard, we calculated the accuracy of the values of the relative PCT infarct size and mismatch that were obtained by using more limited z-axis coverage. The impact of different levels of PCT z-axis coverage on the eligibility for reperfusion treatment was assessed. RESULTS: On the admission PCT, by using 80-mm of z-axis coverage, the mean perfusion infarct core volume was 45.9 ± 44.0 cm(3) (range, 0–170 cm(3)) and the mean penumbra volume was 64.5 ± 64.4 cm(3) (range, 0–226 cm(3)). The mean perfusion infarct core/MCA territory ratio was 19.6% ± 16.2% (range, 0.1%–56%). The penumbra / (infarct + penumbra) ratio was 68.6% ± 23.6% (range, 16.4%–100%). The final infarct volume on follow-up NCCT was 115.4 ± 157.3 cm(3) (range, 1.79–647.4 cm(3)). The minimal z-axis PCT coverage required to obtain values similar to those obtained with 80-mm z-axis coverage was 75 mm for a mismatch of 0.5, fifty millimeters for a mismatch of 0.2, and 55 mm for a size of PCT infarct relative to the MCA territory. CONCLUSIONS: Seventy-five millimeters is the minimal PCT coverage required to use PCT as a tool to select patients with acute stroke for reperfusion therapy by using a mismatch of 0.5. A z-axis coverage of 50 mm was sufficient for a mismatch of 0.2; and 55 mm, for the size of PCT infarct relative to MCA territory (one-third or more).

To evaluate spinal arterial anatomy and identify risk factors for lower extremity weakness (LEW) following endovascular thoracoabdominal aortic aneurysm (TAAA) repair.A retrospective review was conducted of 37 patients (27 men; mean age 74.8+/-7.1 years, range 58-86) undergoing endovascular TAAA repair with branched stent-grafts at a single academic institution from July 2005 to December 2007. Data were collected on preoperative comorbidities, duration of operation, blood loss, type of anesthesia, extent of aortic coverage, blood pressure, cerebrospinal fluid (CSF) pressure and drainage, and postoperative development of LEW. Pre- and postoperative contrast-enhanced computed tomographic angiograms (CTA) in a 26-patient subset were analyzed to evaluate the number of patent intercostal and lumbar arteries before and after repair.All patients were neurologically intact at the end of the operation. Seven (19%) patients developed LEW postoperatively: 6 perioperatively and 1 after discharge. LEW was associated with postoperative hypotension, internal iliac artery (IIA) occlusion, and fewer patent segmental arteries on preoperative CTA. Lowest mean systolic blood pressure was90 mmHg in all 6 (100%) patients who developed LEW in hospital compared to 12 (44%) of the 27 patients who did not develop LEW (p = 0.02). Complete resolution of LEW (n = 4) followed prompt measures to raise blood pressure and lower CSF pressure. Persistent LEW (n = 3) was associated with sustained hypotension from sepsis, postoperative bleeding, and hemodialysis, respectively. Two (29%) of 7 patients with LEW either lost prograde flow to an IIA during repair or had bilaterally occluded IIAs preoperatively compared to 2 (7%) of 30 patients without LEW (p = 0.16). Comparison of pre- and postoperative CTAs showed no reduction in the mean number of patent segmental arteries in patients with or without LEW.Endovascular TAAA repair inevitably occludes direct inflow to lumbar and intercostal arteries. The distal segments of these arteries to the spine, however, are seen to remain patent through collaterals. Measures to preserve collateral pathways and increase perfusion pressure may help prevent or treat LEW.

Primary CNS tumors consist of a diverse group of neoplasms originating from various cell types in the CNS. Brain tumors are the most common solid malignancy in children under the age of 15 years and the second leading cause of cancer death after leukemia. The most common brain neoplasms in children differ consistently from those in older age groups. Pediatric brain tumors demonstrate distinct patterns of occurrence and biologic behavior according to sex, age, and race. This chapter highlights the imaging features of the most common tumors that affect the child's CNS (brain and spinal cord).

Vertebral ossification is not complete in the first half of infancy and sound beam transmits through the cartilage. This combination makes imaging the spinal canal with sonography possible. Sonography is usually the first imaging exam to be performed in infants because of its simplicity, low cost, and lack of deleterious effects. Another advantage of sonography over most imaging modalities is its capacity to visualize the motion of the filum terminale, which is restricted in tethered cord. In this chapter, we discuss the technique, the indications and the imaging findings of the most common disorders involving the infant’s spine, assessed by ultrasound exam.

Dear Sir, We welcome the comments made by Dr. Donmez regarding etiologic factors in the development of posterior reversible encephalopathy syndrome (PRES), in particular the potential contribution of Epstein barr virus (EBV) infection. A large number of disorders have been described in association with PRES in the pediatric population including solid organ and bone marrow transplantation, renal dysfunction, autoimmunity, sepsis, and chemotherapy with hypertension being observed in up to 88 % of children at symptoms onset [1]. As Dr. Donmez points out, additional underlying factors may incite or potentiate the development of PRES such as viral infection or medication effects. Such factors, in addition to hypertension, vary from case to case but are known to be present in most PRES cases in adults and children [1, 2]. Whether hypertension directly contributes to the development of PRES or is instead a downstream effect of an underlying systemic toxicity that affects both the cerebral vasculature (manifesting characteristic MRI and MRA findings) and the renal vasculature (resulting in hypertension) is unclear. In our case, the patient did have a brief period of hypertension which may or may not have contributed to the development of PRES [3]. Taking a step back, it seems plausible that this patient’s hypertension could be attributed to GuillainBarre syndrome (GBS) through altered autonomic regulation of the sympathetic nervous system [4, 5]. Such amechanism is supported by the extensive involvement of upper cervical nerve roots observed in this case and their contribution to the cervical ganglia [3]. Further, this patient had no prior history of hypertension nor has he experienced hypertension following the resolution of the GBS/ PRES episode. The presence of viral markers of EBV may explain the development of GBS; however, we posit that any specific correlation between Epstein Barr viremia and the development of PRES in our case is less robust than our proposed correlation between GBS and PRES. Although PRES is well known to occur in the setting of infection including viral illness [6], sepsis represents the most common scenario in which the development of PRES has been attributed to an infectious etiology [2]. Thus, it is our opinion that among the potential contributing factors in the cascade leading to PRES in this individual, GBS remains at the forefront. In this regard, we have recently observed a statistically significant correlation between systolic blood pressure at symptoms onset and normalized ADC values in 25 children with PRES further supporting the association between vasogenic edema and hypertension [1]. Attempts to isolate a single etiologic factor in PRES development have failed given that PRES is likely a multi-factorial entity. A better understanding of PRES pathophysiology may be likely gained by viewing PRES as a downstream result of a cascade of events which may alter the blood brain barrier homeostasis [7]. * Giulio Zuccoli giulio.zuccoli@gmail.com

The most frequently encountered intracranial pathologies in the neonatal period include hemorrhage (e.g., germinal matrix/intraventricular hemorrhages, intraparenchymal hemorrhages or extraaxial hemorrhages), hypoxic–ischemic injuries (i.e., hypoxic–ischemic encephalopathy, stroke), and encephalopathy of prematurity, which includes both focal and diffuse injury to the developing white matter. Less frequently encountered are congenital malformations involving the cerebrum (e.g., diffuse migrational abnormalities, intrahemispheric cysts) or the posterior fossa (e.g., congenital aqueductal stenosis, chiari malformations), infections, trauma, tumors/masses, and early-onset metabolic disorders.

Isolated fibrous gastric antral band in a neonate causing partial gastric obstruction and mimicking prepyloric antral web is not reported in the English literature, and we would like to report the first case. A premature neonate with feeding difficulties and bilious aspirate underwent upper gastrointestinal contrast examination. The upper gastrointestinal series showed a thin, radiolucent, circumferential band in the antrum with delayed gastric emptying. Radiographic diagnosis of prepyloric antral web with partial gastric obstruction was made. Intraoperatively, a circumferential fibrous cord was found in the muscle layer (tunica muscularis) of the antrum, which was completely divided. Clinically and radiographically, the 2 conditions could not be differentiated but require 2 separate surgical techniques for their management.

The purpose of this study was to identify imaging markers and clinical risk factors that significantly predict the evolution of computed tomography (CT) imaging features of carotid artery atherosclerotic disease over a 1-year period.Our prospective study involved 120 consecutive patients undergoing emergent CT evaluation for symptoms of acute stroke. These patients were asked to consent to a follow-up CT exam in 1 year. To evaluate for atherosclerotic plaque, both at baseline and on follow-up, we employed a comprehensive computed tomography angiography (CTA) protocol that captured the carotid, vertebral, aortic, and coronary arteries. To further evaluate carotid artery plaque components, we used an automated classifier computer algorithm that distinguishes among the histological components of the carotid artery wall (lipids, calcium, fibrous tissue) based on appropriate thresholds of CT density. Baseline values of carotid imaging features and clinical variables were assessed for their ability to significantly predict changes in these imaging features over 1 year.Of these 120 consecutive patients, 17 received both a baseline and a follow-up CTA exam. Wall volume increased more when the largest lipid cluster was located close to the lumen (coefficient -7.61, -13.83 to -1.40, P = .016). The volume of lipid increased with age (coefficient .36, .21 to .50, P = .000), in smokers (coefficient 8.89, 6.82 to 10.95, P = .000) and when fewer lipid clusters were present at baseline (coefficient -0.11, -0.17 to -.04, P = .001). The volume of calcium increased with greater volume of lipid at baseline (coefficient .35, .02 to .68, P = .035) and in patients on statins (coefficient 4.79, 1.73 to 7.86, P = .002).There are a number of imaging markers and risk factors that significantly predict the evolution of CT imaging features of carotid artery atherosclerotic disease over a 1-year period.

This was a prospective, cross-sectional study to evaluate the risk factors and symptoms associated with specific carotid wall and atherosclerotic plaque features as seen on computed tomography-angiography (CTA) studies.A total of 120 consecutive consenting patients admitted to the emergency department with suspected cerebrovascular ischemia, and receiving standard-of-care CTA of the brain and neck on a 64-slice CT scanner, were prospectively enrolled in the study. The carotid wall features observed on CT were quantitatively analyzed with customized software using different radiodensities for contrast-phase acquisition of the carotids. Clinical datasets, including a complete medical history and examination, were obtained by research physicians or specially trained associates blinded to any findings on CT. Univariate and multivariate analyses were performed to assess the degree of association between clinical indicators and quantitative CT features of carotid atherosclerotic plaques.Men tended to have increased carotid lumen (coefficient: 608.7; 95% CI: 356.9-860.6; P0.001) and wall volumes (209.2; 54.5-364.0; P=0.008), and hypertension was associated with increased wall volume (260.6; 88.7-432.6; P=0.003). Advanced age was associated with increases in maximum wall thickness (0.02; 0.003-0.05; P=0.029), fibrous cap thickness (0.005; 0.001-0.008; P=0.016) and number of calcium voxels (2.7; 1.25-4.2; P0.001), and the presence of a carotid bruit was associated with carotid stenosis length (21.0; 5.38-37.8; P=0.009). Exercise was inversely related to the number of calcium (-37.1; -71.5 - -2.7; P=0.035) and lipid (-7.9; -15.1 - -0.7; P=0.032) voxels. ACE inhibitor use was associated with fibrous cap thickness (0.1; 0.04-0.23; P=0.005).Significant associations were found between clinical descriptors and carotid atherosclerotic plaque features as revealed by CT. Future studies are needed to validate our findings, and to continue investigations into whether CT features of carotid plaques can be used as biomarkers to quantify the impact of strategies aiming to correct vascular risk factors.

OBJETIVO: Propõe-se avaliar o papel do tensor de difusão na avaliação dos diferentes padrões de acometimento da substância branca em pacientes com tumores cerebrais e a utilidade desta técnica no diagnóstico diferencial dessas neoplasias. MATERIAIS E MÉTODOS: Quarenta e quatro pacientes com tumores cerebrais, incluindo gliomas de baixo grau, astrocitomas anaplásicos, glioblastomas multiformes e metástases, foram estudados com imagens de ressonância magnética convencional e tensor de difusão. Os tratos de substância branca próximos aos tumores foram caracterizados como deslocados, interrompidos, infiltrados e edematosos. RESULTADOS: Houve significativa sobreposição entre os padrões de acometimento da substância branca pelo tensor de difusão, uma vez que o padrão deslocado foi observado em todos os tipos de tumor. Os padrões interrompido e infiltrado foram encontrados em glioblastomas multiformes e astrocitomas anaplásicos e o padrão edematoso foi observado em metástases. CONCLUSÃO: Os padrões de envolvimento dos tratos de substância branca cerebral avaliados pelo tensor de difusão auxiliam no mapeamento dos tratos adjacentes aos tumores e fornecem informações importantes sobre a extensão do tumor, no entanto, eles não possibilitam fazer a distinção entre gliomas de baixo e alto graus e metástases OBJECTIVE: The present study was aimed at evaluating the role of diffusion tensor imaging for the assessment of different patterns of white matter involvement in patients with brain tumors and the utility of this technique for differential diagnosis of such neoplasms. MATERIALS AND METHODS: Forty-four patients with brain tumors, including low-grade gliomas, anaplastic astrocytomas, glioblastomas multiforme and metastases, were studied with conventional and diffusion tensor magnetic resonance imaging. White matter tracts around the tumors were characterized as displaced, disrupted, infiltrated and edematous. RESULTS: A significant overlap was observed between patterns of white matter involvement on diffusion tensor images as the displaced pattern was seen in all the types of tumor. Disrupted and infiltrated patterns were found in glioblastomas multiforme and anaplastic astrocytomas. The edematous pattern was found in the cases of metastases. CONCLUSION: Diffusion tensor imaging patterns of white matter involvement assists in the mapping of tracts adjacent to tumors, providing significant data about tumors extent; however, they cannot distinguish low-grade and high-grade gliomas from metastases

BACKGROUND AND PURPOSE: Ischemic stroke is commonly embolic, either from carotid atherosclerosis or from cardiac origin. These potential sources of emboli need to be investigated to accurately prescribe secondary stroke prevention. Moreover, the mortality in ischemic stroke patients due to ischemic heart disease is greater than that of age-matched controls, thus making evaluation for coronary artery disease important in this patient population. The purpose of this study was to evaluate the image quality of a comprehensive CTA protocol in patients with acute stroke that expands the standard CTA coverage to include all 4 chambers of the heart and the coronary arteries. MATERIALS AND METHODS: One hundred twenty patients consecutively admitted to the emergency department with suspected cerebrovascular ischemia undergoing standard-of-care CTA were prospectively enrolled in our study. We used an original tailored acquisition protocol using a 64-section CT scanner, consisting of a dual-phase intravenous injection of iodinated contrast and saline flush, in conjunction with a dual-phase CT acquisition, ascending from the top of the aortic arch to the vertex of the head, then descending from the top of the aortic arch to the diaphragm. No beta blockers were administered. The image quality, attenuation, and CNRs of the carotid, aortic, vertebral, and coronary arteries were assessed. RESULTS: Carotid, aorta, and vertebral artery image quality was 100% diagnostic (rated good or excellent) in all patients. Coronary artery image quality was diagnostic in 58% of RCA segments, 73% of LAD segments, and 63% of LCX segments. When we considered proximal segments only, the diagnostic quality rose to 71% in the RCA, 83% in the LAD, and 74% in the LCX. CONCLUSIONS: Our stroke protocol achieved excellent opacification of the left heart chambers, the cervical arteries, and each coronary artery, in addition to adequate carotid and coronary artery image quality.

This study aimed to assess the potential of 64-slice MDCT in characterizing revascularized infarcted myocardium at the cellular and microvascular levels. Pigs (n=7) underwent 2 h left anterior descending coronary artery occlusion/reperfusion. In acute (2-4 h) and subacute (1 week) infarction, first-pass perfusion (FPP) (1 ml/kg of 300 mg/ml Omnipaque) was performed using a cine (rotation time 60 s/bpm) non-ECG gated sequence (mAS/kV=100/120). Delayed contrast enhanced images (DE) (mAS/kV=650/120) were acquired every 2 min for 10 min to determine the kinetics of Omnipaque and to define infarcted myocardium and microvascular impairment (representing microvascular obstruction and/or no- or low-reflow phenomenon). Maximum upslope, maximum attenuation and time to the peak were measured from FPP plots. 2,3,5-Triphenyltetrazolium-chloride (TTC) was used to define true infarction in the excised hearts. Hyperenhanced myocardium on DE was measured and compared with TTC. The contrast media caused minor beam hardening and X-ray scatter on FPP. The above-mentioned perfusion parameters significantly differed between remote and acute infarction. Infarcted myocardium showed two patterns of enhancement on DE, hyperenhanced rim representing the perfused infarction and hypoenhanced core representing a microvascular impaired region, with significantly different attenuation. The extent of infarction on DE-MDCT decreased over the course of 1 week and did not differ from TTC. Post-processed FPP semi-quantitative images showed a decline in myocardial blood volume and flow in acute revascularized infarction. In conclusion, modern MDCT has the potential to identify residual ischemia on FPP and microvascular impairment and infarction on DE images. (Less)

Objective: The purpose of this study was to assess how imaging findings on admission perfusion CT (PCT) and follow-up noncontrast CT (NCT), and their changes over time, correlate with clinical scores of stroke severity measured on admission, at discharge and at 6-month follow-up. Methods: Fifty-two patients with suspected hemispheric acute ischemic stroke underwent a PCT within the first 24 h of symptom onset and a follow-up NCT of the brain between 24 h and 3 months after the initial stroke CT study. NIH Stroke Scale (NIHSS) scores were recorded for each patient at admission, discharge and 6 months; modified Rankin scores were determined at discharge and 6 months. Baseline PCT and follow-up NCT were analyzed quantitatively (volume of ischemic/infarcted tissue) and semiquantitatively (anatomical grading score derived from the Alberta Stroke Program Early CT Score). The correlation between imaging volumes/scores and clinical scores was assessed. Analysis was performed for all patients considered together and separately for those with right and left hemispheric strokes. Results: Significant correlations were found between clinical scores and both quantitative and semiquantitative imaging. The volume of the acute PCT mean transit time lesion showed best correlation with admission NIHSS scores (R2 = 0.61, p < 0.001). This association was significantly better for left hemispheric strokes (R2 = 0.80, p < 0.001) than for right hemispheric strokes (R2 = 0.39, p = 0.131). Correlation between imaging and NIHSS scores was better than correlation between imaging and modified Rankin scores (p = 0.047). The correlation with discharge clinical scores was better than that with 6-month clinical scores (p = 0.012). Conclusions: Baseline PCT and follow-up NCT volumes predict stroke severity at baseline, discharge and, to a lesser extent, 6 months. The correlation is stronger for left-sided infarctions. This finding supports the use of PCT as a surrogate stroke outcome measure.