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AbstractNearly one in five children with CHD is born with white matter injury that can be recognised on postnatal MRI by the presence of T1 hyperintense lesions. This pattern of white matter injury is known to portend poor neurodevelopmental outcomes, but the exact aetiology and histologic characterisation of these lesions have never been described. A fetal sheep was cannulated at gestational age 110 days onto a pumpless extracorporeal oxygenator via the umbilical vessels and supported in a fluid environment for 14.5 days. The fetus was supported under hypoxic conditions (mean oxygen delivery 16 ml/kg/day) to simulate the in uteroconditions of CHD. At necropsy, the brain was fixed, imaged with MRI, and then stained to histologically identify areas of injury. Under hypoxemic in uteroconditions, the fetus developed a T1 hyperintense lesion in its right frontal lobe. Histologically, this lesion was characterised by microvascular proliferation and astrocytosis without gliosis. These findings may provide valuable insight into the aetiology of white matter injury in neonates with CHD.

The management of patients with symptomatic rectal masses can be challenging and is further complicated in cases of advanced age, comorbidities, prior surgeries, and acute hemorrhage. In this report, we describe a patient who presented with massive hemorrhage from a 7 cm low rectal tumor with subsequent cardiac arrest. After return of spontaneous circulation, emergent pelvic angiography identified extensive tumor enhancement and blush off the anterior division of the right internal iliac artery from multiple parasitized vessels. The right internal iliac artery was embolized with multiple microcoils to decrease the tumor blood supply and slow the rate of bleeding. The patient was then taken directly from the angiography suite to radiation oncology for planning CT, and within several hours, underwent his first session of radiation. In conjunction with angioembolization, short-course radiation therapy can be an effective treatment modality for advanced bleeding rectal tumors not amenable to surgical resection.

ABSTRACT This paper investigates the effect of filler particle size on the fatigue and low temperature toughening mechanisms in bitumen mastics, polymer modified bitumen and asphalt mixtures by using glass [...]

Neuroimaging findings in immune effector cell associated neurotoxicity syndrome (ICANS) have not been systematically described. To address this gap in knowledge, we created a retrospective database (CARNIVAL) of neuroimaging studies obtained in patients with hematologic malignancies who received CAR T cell therapy (CAR T) at 6 pediatric institutions within the CARNATION consortium.

Tuberculosis has reemerged as a serious national problem. From 1985 through 1993, the number of new cases of tuberculosis increased 14%. An estimated 10 to 15 million persons in the [...]

Although vast, the medical literature is deficient in reports of gastroesophageal junction (GEJ) involvement of mantle cell lymphoma (MCL). We present the unique case of a 76-year-old male who presented with worsening dysphagia, weight loss, and heartburn and who was found to have blastic variant of MCL in the GEJ. He had undergone extensive workup in the past for an ulcerative, gastric/GEJ lesion, found on four separate esophagogastroduodenoscopies (EGDs) and two esophageal ultrasounds, whose biopsies were repeatedly negative for malignancy. On admission, physical examination and labs were unremarkable, but computed tomography showed an irregular mass involving the GEJ. EGD on admission showed a large friable, ulcerated lesion with heaped-up margins involving the GEJ whose biopsies showed histological and immunohistochemical (IHC) findings consistent with blastic MCL. A bone marrow biopsy showed minimal involvement (<5%) of CD5+/CD23+ B cells and was negative for both cyclin D1 and t(11;14). The biopsy of the lesion was diffusely infiltrated by atypical lymphocytes with prominent nucleoli and IHC stains positive for CD20, cyclin D1, BCL-2, and BCL-6 as well as a Ki-67 proliferative index >90%, all consistent with blastic MCL, a rare and aggressive subtype of MCL. He was started on guideline-based chemoimmunotherapy as he was not a candidate for stem cell transplantation. Repeat imaging 1 year later showed improvement of the mass, with negative endoscopic biopsies for lymphoma. This case provides additional distinct features to the various clinical presentations associated with this rare proliferative disorder, thereby enhancing the medical literature on MCL.

Knowledge of the diagnostic imaging clues, clinical and imaging findings, and main differential diagnoses of primary mitochondrial disorders of the pediatric central nervous system is useful in reaching a diagnosis or narrowing the differential diagnosis.

Add “improving” before “detection”? PET/MR is beneficial particularly in pediatric patients who undergo recurrent imaging, such as those with cancer or chronic inflammatory disease. PET/MR has advantages compared with PET/computed tomography, including decreased radiation exposure and superior characterization of soft tissue. Ongoing challenges include reducing examination duration and costs and detection of pulmonary lesions. Accepted clinical applications of PET/MR in pediatric patients are evaluation of epileptic foci and diagnosis, staging, and follow-up of solid tumors. PET/MR also may have a role in diagnosis and management of infectious and inflammatory conditions relevant to the pediatric population, including osteomyelitis and Crohn disease.

The simplest approach to convey the results of scientific analysis, which can include complex comparisons, is typically through the use of visual items, including figures and plots. These statistical plots play a critical role in scientific studies, making data more accessible, engaging, and informative. A growing number of visual representations have been utilized recently to graphically display the results of oncologic imaging, including radiomic and radiogenomic studies. Here, we review the applications, distinct properties, benefits, and drawbacks of various statistical plots. Furthermore, we provide neuroradiologists with a comprehensive understanding of how to use these plots to effectively communicate analytical results based on imaging data.

This article has been retracted at the request of the Editor-in-Chief. The authors have taken the majority of content in this paper from Benjamin Smith's thesis [LOW-TEMPERATURE AND DYNAMIC FATIGUE [...]

Elevated levels of choline are generally emphasized as marker of increased cellularity and cell membrane turnover in gliomas. In this study, we investigated the incidence rate of lack of choline/creatine and choline/water elevation in a population of grade I–III gliomas. A cohort of 41 patients with histopathologically confirmed gliomas underwent multi-voxel proton magnetic resonance spectroscopy on a 3 T magnetic resonance system prior to treatment. Peak areas for choline and myoinositol were measured from all voxels that exhibited hyperintensity on fluid-attenuated inversion recovery images and were normalized to creatine and unsuppressed water from each voxel. The average metabolite/creatine and metabolite/water ratios from these voxels were then computed. Similarly, average metabolite ratios were computed from normal brain parenchyma. Gliomas were considered for lack of choline elevation when choline/creatine and choline/water ratios from neoplastic regions were less than those from normal brain parenchyma regions. Six of 41 (14.6%) grade I–III gliomas showed lack of elevation for choline/creatine and choline/water ratios compared to normal brain parenchyma. Four of these six gliomas also demonstrated elevated levels of myoinositol/creatine ratio. All other gliomas (n= 35) had elevated choline levels from neoplastic regions relative to normal parenchyma. The sensitivity of choline/creatine or choline/water in determining a grade I–III glioma was 85.4%. These findings suggest that a lack of choline/creatine or choline/water elevation may be seen in some gliomas and low choline levels should not prevent us from considering the possibility of a grade I–III glioma.

PET/MR imaging is an integrated imaging system that combines the high soft tissue resolution of MR imaging with the quantitative data obtained from PET into a single system. It is a relatively new imaging technique but with potential clinical use in pediatric oncologic and nononcologic processes in additional to its role in research. It is particularly relevant in pediatric patients due to reduced radiation burden compared with PET/CT and the ability to obtain exquisite functional and anatomic imaging in a single imaging session, thereby reducing the number of anesthesia/sedations. This review article focuses on the current as well as future applications of PET/MR imaging in pediatric imaging, including both oncologic and nononcologic indications.

Brain growth charts derived from pediatric clinical brain MRI scans with limited imaging pathology were highly correlated with charts derived from scans in research control participants.

Primary central nervous system lymphoma (PCNSL) is a rare aggressive high-grade type of extranodal lymphoma. PCNSL can have a variable imaging appearance and can mimic other brain disorders such as encephalitis, demyelination, and stroke. In addition to PCNSL, the CNS can be secondarily involved by systemic lymphoma. Computed tomography and conventional MRI are the initial imaging modalities to evaluate these lesions. Recently, however, advanced MRI techniques are more often used in an effort to narrow the differential diagnosis and potentially inform diagnostic and therapeutic decisions.

The familiar phrase “time is brain” may be more correctly rephrased “time and penumbra are brain” because several clinical trials have demonstrated that IV alteplase and endovascular thrombectomy treatment windows can be extended when patients have favorable diffusion-perfusion mismatch profiles.1-3Collateral circulation protects the brain by minimizing and preventing expansion of the ischemic core.4Favorable collaterals have been associated with better recanalization rates, radiographic outcomes, and patient outcomes.4Several collateral grading systems and assessments are available and rely on imaging techniques that can directly visualize collaterals such as catheter angiography, magnetic resonance angiography, and CT angiography or perfusion techniques that may indirectly provide information about the robustness of collateral circulation.4Collateral grading systems have not been validated in cohorts of children with stroke.

The present article deals with the nonlinear vibration and instability analysis of a bonded double-smart composite microplate system (DSCMPS) conveying microflow based on nonlocal piezoelasticity theory. Two microplates are connected together by visco-Pasternak medium and both of them made of poly-vinylidene fluoride reinforced by double walled boron nitride nanotubes (DWBNNTs). Modified Navier–Stokes relation is used to evaluate fluid–microplate interaction considering the effects of bulk viscosity and slip boundary condition. Energy method and Hamilton's principle are employed to derive motion equations with regard to von Kármán geometric nonlinearity. Also, charge equation is used to consider electromechanical coupling. Due to existence of nonlinear terms, the governing equations are solved with the help of the differential quadrature method (DQM). A detailed parametric study is conducted to elucidate the effects of the flow velocity, fluid viscosity, Knudsen number, type of elastic medium, temperature change, small scale, aspect ratio, volume fraction, and orientation angle of the DWBNNTs on the vibration and instability behaviors of the coupled DSCMPS. This study might be helpful for the design of nano-electro-mechanical systems/ micro-electro-mechanical systems.

Background:Currently two magnetic resonance imaging (MRI) methods have been used to assess periventricular leukomalacia (PVL) severity in infants with congenital heart disease: manual volumetric lesion segmentation and an observational categorical scale. Volumetric classification is labor intensive and the categorical scale is quick but unreliable. We propose the quartered point system (QPS) as a novel, intuitive, time-efficient metric with high interrater agreement.Methods:QPS is an observational scale that asks the rater to score MRIs on the basis of lesion size, number, and distribution. Pre- and postoperative brain MRIs were obtained on term congenital heart disease infants. Three independent observers scored PVL severity using all three methods: volumetric segmentation, categorical scale, and QPS.Results:One-hundred and thirty-five MRIs were obtained from 72 infants; PVL was seen in 48 MRIs. Volumetric measurements among the three raters were highly concordant (?c = 0.94–0.96). Categorical scale severity scores were in poor agreement between observers (? = 0.17) and fair agreement with volumetrically determined severity (? = 0.26). QPS scores were in very good agreement between observers (? = 0.82) and with volumetric severity (? = 0.81).Conclusion:QPS minimizes training and sophisticated radiologic analysis and increases interrater reliability. QPS offers greater sensitivity to stratify PVL severity and has the potential to more accurately correlate with neurodevelopmental outcomes.

The spheno-occipital synchondrosis (SOS) is a critical component of midfacial and cranial base growth. Premature closure has been associated with midface hypoplasia in animal models and syndromic craniosynostosis subpopulations with Apert and Muenke syndromes. To link premature SOS closure and midface hypoplasia in patients with Pfeiffer syndrome, a retrospective case-control study was performed in patients treated at a large craniofacial center between 1982 and 2012 diagnosed with Pfeiffer syndrome. At least 1 computed tomography (CT) scan was required to assess SOS patency. Age-sex-matched control CT scans were also assessed for SOS patency. Three independent reviewers with high interrater reliability ( = 0.88) graded SOS patency as open, partially closed, or completely closed. Wilcoxon rank sum test compared the Pfeiffer patients with control subjects.

We present a case of focal cerebral arteriopathy and ischemic stroke in a pediatric patient with coronavirus disease 2019 who presented with seizure, right hemiparesis, and dysarthria with positive findings for severe acute respiratory syndrome coronavirus 2 from nasopharyngeal swab and cerebral spinal fluid.

The spheno-occipital synchondrosis is a driver of cranial base and facial growth. Its premature fusion has been associated with midface hypoplasia in animal models. The authors reviewed computed tomographic scans of patients with Apert and Muenke syndrome, craniosynostosis syndromes with midface hypoplasia, to assess premature fusion of the spheno-occipital synchondrosis when compared with normal controls.

The objective of this study was to describe the occurrence of hemorrhagic transformation (HT) among children with arterial ischemic stroke within 30 days after symptom onset and to describe clinical factors associated with HT.

Fluorodeoxyglucose (FDG)-PET has expanding applications in the field of interventional radiology. FDG-PET provides both qualitative and quantitative assessments of malignancy, infection, and inflammation. These assessments can assist interventional radiologists in selecting the most appropriate treatment options for their oncology patients. FDG-PET is also useful for evaluating the response to interventional treatments and in predicting the prognosis of oncology patients. Finally, FDG-PET can assist the interventional radiologist in diagnosing and monitoring response to treatment of infection and inflammation. Nevertheless, there is a need for additional prospective studies to further establish the role of FDG-PET in these applications.

Introduction:Single ventricle patients develop aortopulmonary collaterals (APC) whose flow (APCF) has been shown, in a cross-sectional study, to be inversely proportional to cerebral blood flow (CBF). Serial longitudinal CBF and APCF data in Fontan patients taking into account brain injury (BI) has never been reported. Decreased CBF may adversely impact neurodevelopmental outcome.Methods:A prospective longitudinal cohort of 27 Fontan patients (age 10+1.9 years, 74% male) underwent cardiac and brain MRIs 3-9 months after Fontan and 6.0+1.86 years afterwards to measure CBF, APCF and to assess BI (grouped into focal brain injury (FBI), generalized insult (GI) and hemorrhage). CBF was measured using jugular venous flow and APCF was measured by the difference between aortic flow and caval return. A multivariate linear regression model was used to assess the relationship between change in APCF and change in CBF controlling for time since Fontan, sex, and changes in BI.Results:Demographics, flow and BI data are shown in table 1. A strong inverse relationship was found between CBF and APCF when CBF was indexed to aortic flow and APCF was indexed to BSA (R^2 = 0.72, P<0.01). Overall, CBF decreased by 9+11% and APCF decreased by 0.73+0.67 l/min/m^2 (12% when indexed to aortic flow). CBF and APCF were significantly and inversely related when adjusting for time since Fontan, sex, and change in the visibility of BI on MRI. Each one unit increase in APCF was associated with an 8% decrease in CBF. Change in CBF was smaller for those with longer times since Fontan and was larger for males. Change in CBF was larger for those whose FBI or GI became less visible, but smaller for those whose hemorrhages became less visible. See table 2.Conclusion:CBF and APCF are inversely related across serial imaging, adjusting for time from Fontan, sex and BI. This may adversely impact neurodevelopment. As APCs can be embolized, this may be a modifiable risk factor. A large scale trial is warranted.

Stroke is relatively rare in children but has become increasingly recognized clinically. Hemiplegic migraine (HM) is a rare subtype of migraine, with attacks typically beginning in childhood or adolescence. Attacks are characterized by migraine headaches and motor weakness, which develop over several minutes. HM may therefore mimic acute stroke; however, symptoms last less than an hour and resolve spontaneously, often without sequela.1–4Distinction between these entities is important due to their different urgency and management. Neuroimaging is indispensible in working up patients presenting to the Emergency Department with stroke-like symptoms and can be used to distinguish between infarction and HM.

Efficient processing of unlimited and continuously expanding sequences of data items is one of the key factors in the implementations of Data Stream Management Systems (DSMS). Analysis of stream processing at the dataflow level reveals execution plans which are not visible at a logical level. This work introduces a new model of data stream processing and discusses a number of optimization techniques applicable to this model and its implementation. The optimization techniques include applications of containers with intermediate results, analysis of data processing rates, and efficient synchronization of elementary operations on data streams. The paper also describes the translation of logical level expressions on data streams into the sets of dataflow level expressions, syntax based optimization of dataflow expression, and scheduling of concurrent computations of the dataflow expressions.

Thiamine-responsive megaloblastic anemia (TRMA) is a rare autosomal recessive syndrome characterized by megaloblastic anemia, deafness, and diabetes mellitus. A genome scan previously established linkage of this disorder to 1q23 and haplotype analysis defined a 16-cM critical region. Molecular genetic analyses of four unrelated multiplex Iranian families inheriting TRMA confirmed linkage to the same region and identified recombinant chromosomes which permitted refinement of the critical region to a narrow 1.4-cM interval. The haplotypes of the families differed, consistent with at least two independent mutational events. This refinement of the TRMA locus to less than 10% of that previously published should markedly facilitate the identification and evaluation of positional candidate and novel genes which may cause this disorder.

Two series of isoxazoles substituted by long alkyl or alkenyl chains in the α position with respect to the oxygen atom or in the α position with respect to the two heteroatoms have been synthesized. Starting from 3,5-dimethylisoxazole, the regioselective metalation/alkylation on the α-O methyl group was a very convenient route to a large variety of "α-O substituted isoxazoles". When applied to α-O methylated isoxazoles bearing an α-N alkenyl chain the same method provides an original unequivocal approach to 3,5-dialkenyl isoxazoles. An alternative route to these compounds, despite the formation of di-isoxazoline as by-product and an additional step corresponding to the oxidation of the intermediate isoxazoline, is the 1,3-dipolar cycloaddition, by using terminal dienes as dipolarophiles with alkenyl dipoles. Nevertheless, the cycloaddition between monoalkylated alcynes and alkylated dipoles remains the most straightforward synthesis of 3,5-dialkyl isoxazoles. Keywords: isoxazoles, alkenyl side chains, metalation–alkylation, regioselectivity.

Levels of testosterone-oestradiol binding globulin (TeBG) were measured by a precipitation technique in terms of dihydrotestosterone-5α (DHT) binding capacity in children, adult males and females, pregnant and hirsute women and women with various trophoblastic disorders. It was found that TeBG levels in children of either sex (1.92 ± 0.16 μg DHT bound/100 ml serum) approached the normal female range (2.31 ± 0.11) and were distinctly higher than those of the adult male (1.04 ± 0.09). In both pregnancy and trophoblastic disease (hydatidiform mole and choriocarcinoma but not metastatic choriocarcinoma) TeBG levels were elevated (17.5 ± 0.70 and 14.9 ± 1.49, respectively). In hirsutism TeBG was depressed (1.17 ± 0.09) and comparable with the levels in normal male subjects. A number of other parameters, HCG, oestradiol-17β, testosterone and progesterone were measured and found to be similar to those previously reported in the literature. It appears that TeBG titre might provide an additional index in following the prognosis of trophoblastic disorders, besides HCG measurement.

Extract: Neutrophil lobe averages and hypersegmentation, bone marrow examinations, serum folate and vitamin B12levels, and formiminoglutamic acid (FIGLU) excretion studies were performed in a group of 55 infants and children with iron deficiency anemia, some with and some without thrombocytopenia. Increase lobe averages (> 3.71) and hypersegmentation were found in 13 and 32 patients, respectively. Twenty-five patients demonstrated some megaloblastic changes in their marrow. None had decreased serum levels of vitamin B12; two were considered folic acid deficient, based on serum folate assays (< 3 ng/ml). Three had elevated urinary levels of FIGLU (> 6.6 µmol/h). In only five instances could a correlation be established between the morphologic and biochemical findings.The presence or absence of thrombocytopenia did not appear to be related to megaloblastic morphologic changes in the blood and bone marrow or to the number of bone marrow megakaryocytes.Speculation: It is postulated that some of the changes in peripheral blood and bone marrow found in iron deficiency states are due to a relative lack of folate or vitamin B12at the tissue level resulting from hyperplasia. The exact mechanism for the thrombocytopenia is not clear.

Rare histologic variants of esophageal cancer account for about 5% of cases. As its name suggests, polypoid spindle cell carcinoma of the esophagus (carcinosarcoma, pseudosarcoma) is comprised of both epithelial and spindle cell elements. The nomenclature reflects both the historical controversy over the lesion's cell of origin as well as its characteristic fungating intraluminal growth pattern. The authors report a case of polypoid spindle cell carcinoma of the esophagus that was preoperatively diagnosed as a visceral sarcoma.

The epidemiological pattern of Hodgkin disease (HD) was studied in 139 Iranian children with an age range of 2.5–15 years (mean age 8.3) over a 17-year period (1972–1989). The main features observed were: a high male to female ratio of 3.2∶1, a high frequency of HD in toddlers and young school children (73%), the prevalence of mixed cellularity subtype (74.5%) and rare occurrence of lymphocyte depletion subtype (2%) the high occurrence of constitutional symptoms (57%) and the high rate of stage III and IV patients (73.5%). Response to the treatment consisting mainly of chemotherapy and/or radiotherapy was favourable and overall and disease-free survival rates of 91.4% and 74.2% were achieved over a follow up period of 6 months −17 years. According to these findings the epidemiological pattern of Iranian children with HD is similar to that occurring in rural areas of developed countries.

No relevant conflicts of interest to declare.

Imaging reveals increased structural and functional plasticity in human visual pathways after retinal gene therapy.

Background:The incidence of rectal ca rose in the 2nd half of this century,among minority groups and veterans. Rectal ca remains a major problem in the US.It is estimated that more than 45,000 new cases are diagnosed annually in the US and about 15,000 of those will die. Survival for rectal ca treated with curative surgery has not changed over the last several decades and remains in the 45% to 65% range.We assessed the prevalence of rectal ca at VANJHCS over the past ten years. Methods:We reviewed the records of 600 patients at VANJHCS diagnosed with rectal mass from 1/88 to 1/98. The clinical indications for endoscopy were: rectal bleeding, heme + stool, wt loss, change in bowel habits, family history of colorectal ca, colorectal ca screening age >50 and/or severe microcytic anemia. The endoscopies and biopsies were done at East Orange and Lyons Veterans Hospitals. Each patient was given only one histological diagnosis. Results: Out of 600 patients diagnosed with rectal mass over the past ten years at VANJHCS, the incidence of rectal ca was 42% (250/600),tubulovillous adenoma 16%(97/600),tubular adenoma 20%(120/600), adenomatous polyps 14%(81/600), Villous adenoma 5%(32/600) and others 3%(20/600) which included Kaposi's Sarcoma, Leiomyoma, Carcinoids and Leukemia. Conclusions: Etiologic studies are needed to understand the large increases in the incidence of rectal ca and tubulovillous adenoma among the VANJHCS.