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Cranial computed tomography in purulent meningitis of childhood 总被引:3,自引:0,他引:3
Tuncer O Caksen H Arslan S Atas B Uner A Oner AF Odabas D 《The International journal of neuroscience》2004,114(2):167-174
The cranial computed tomography (CT) findings of 48 children with purulent meningitis were examined, prospectively, to determine the importance of cranial CT findings on the prognosis of childhood meningitis, in a developing country. The age of children ranged from 2 months to 13 years. Of 48 patients, 29 (60.5%) survived without sequelae, 13 (27%) survived with sequelae, and six (12.5%) died. Cranial CT was normal in 21 (43%) patients of 48 children with meningitis at admission. Abnormal CT findings were detected in 10, 11, and 6 children in the groups of survived without sequelae, survived with sequelae, and deaths, respectively, at admission (p <.05) We found that CT scan results were correlated with neurological signs (p <.05). At least one or more cranial CTs were was re-taken in children in whom the first CT revealed abnormal findings; we did not find a statistically significant difference for the follow-up CT findings between the groups (p >.05). Hydrocephalus and subdural effusion were the commonest abnormal CT findings. In conclusion, our findings showed that cranial CT may safely be used to detect intracranial complications of meningitis in childhood and the ratio of sequelae and death were more common in children with abnormal cranial CT than those of normal cranial CT findings. Additionally, there was a positive correlation between CT scan results and neurological signs. 相似文献
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Asli Kurne Kader K. Oguz Aysegul Oz Aksu Coşkun Yarar Özgur Duman Semra Hız Kurul Ayşe Serdaroglu Banu Anlar 《Brain & development》2010
Background: Several diagnostic imaging criteria are being described and examined in pediatric multiple sclerosis (MS). Compared to adults, children are more likely to experience acute or relapsing demyelinating episodes of various etiologies which show similar clinical and magnetic resonance imaging (MRI) findings. Aim: To investigate the fulfillment of MRI diagnostic criteria at initial episode in pediatric MS. Methods: We reviewed our series of children and adolescents with the final diagnosis of clinically definite MS and applied the McDonald dissemination in space (DIS) and KIDMUS criteria to their initial MRI scans. Results: Thirty patients (17 girls, 13 boys), most with brainstem dysfunction and polysymptomatic presentation, were included in the study. Twenty-five (83.3%) patients fulfilled both McDonald and KIDMUS criteria. Patients who did not meet any McDonald DIS criteria did not meet KIDMUS criteria either. Only one patient met the McDonald criteria but not the KIDMUS criteria because of the absence of lesions perpendicular to corpus callosum. Conclusions: Our results show 5/30 (16.6%) of MS patients may not present the diagnostic MRI features initially. The variable sensitivity observed for the current MRI criteria in different series can be due to referral biases, differences between populations and length of follow-up, and the definition of MS patients by two attacks only. 相似文献
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Andrew W. Silagy Cihan Duzgol Julian Marcon Renzo G. DiNatale Roy Mano Kyle A. Blum Ed Reznik Martin H. Voss Robert J. Motzer Jonathan A. Coleman Paul Russo Oguz Akin A. Ari Hakimi 《Canadian Urological Association journal》2020,14(12):E625
IntroductionNew radiological tools can accurately provide preoperative three-dimensional spatial assessment of metastatic renal cell carcinoma (RCC). We aimed to determine whether the distribution, volume, shape, and fraction of RCC resected in a cytoreductive nephrectomy associates with survival.MethodsWe retrospectively reviewed 560 patients undergoing cytoreductive nephrectomy, performing a comprehensive volumetric analysis in eligible patients of all detectable primary and metastatic RCC prior to surgery. We used Cox regression analysis to determine the association between the volume, shape, fraction resected, and distribution of RCC and overall survival (OS).ResultsThere were 62 patients eligible for volumetric analysis, with similar baseline characteristics to the entire cohort, and median survivor followup was 34 months. Larger primary tumors were less spherical, but not associated with different metastatic patterns. Increased primary tumor volume and tumor size, but not the fraction of tumor resected, were associated with inferior survival. The rank of tumors based on unidimensional size did not completely correspond to the rank by primary tumor volume, however, both measurements yielded similar concordance for predicted OS. Larger tumor volume was not associated with a longer postoperative time off treatment.ConclusionsPrimary tumor volume was significant for predicting OS, while the fraction of disease resected did not appear to impact patient outcomes. Although rich in detail, our study is potentially limited by selection bias. Future temporal studies may help elucidate whether the primary tumor shape is associated with tumor growth kinetics. 相似文献
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Efe Ilicak Suheyla Cetin Elif Bulut Kader Karli Oguz Emine Ulku Saritas Gozde Unal Tolga Çukur 《NMR in biomedicine》2016,29(5):532-544
Image quality in non‐contrast‐enhanced (NCE) angiograms is often limited by scan time constraints. An effective solution is to undersample angiographic acquisitions and to recover vessel images with penalized reconstructions. However, conventional methods leverage penalty terms with uniform spatial weighting, which typically yield insufficient suppression of aliasing interference and suboptimal blood/background contrast. Here we propose a two‐stage strategy where a tractographic segmentation is employed to auto‐extract vasculature maps from undersampled data. These maps are then used to incur spatially adaptive sparsity penalties on vascular and background regions. In vivo steady‐state free precession angiograms were acquired in the hand, lower leg and foot. Compared with regular non‐adaptive compressed sensing (CS) reconstructions (CSlow), the proposed strategy improves blood/background contrast by 71.3 ± 28.9% in the hand (mean ± s.d. across acceleration factors 1–8), 30.6 ± 11.3% in the lower leg and 28.1 ± 7.0% in the foot (signed‐rank test, P < 0.05 at each acceleration). The proposed targeted reconstruction can relax trade‐offs between image contrast, resolution and scan efficiency without compromising vessel depiction. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Kevser Tural Ozkan Ozden Zeynep Bilgi Emre Kubat Celal Sahin Ermutlu Oguz Merhan Irfan Tasoglu 《The journal of spinal cord medicine》2021,44(5):704
Context: Both copper and betanin have been implicated as having significant bioactivity against ischemic damage in a variety of experimental and clinical settings. The aim of this study is to investigate whether betanin and copper have any protective effect on spinal cord in an ischemia–reperfusion (I/R) model in rats.Design: Spraque-Dawley rats were used in four groups: Sham group (n = 7), control group (laparotomy and cross-clamping of aorta, n = 7), betanin treatment group (dosage of 100 mg/kg of betanin administered intraperitoneally (i.p.) 60 min before laparotomy, n = 7), copper sulfate treatment group (administered copper sulfate i.p. at a dose of 0.1 mg/kg/day for 7 days before laparotomy, n = 7). Malondialdehyde (MDA), glutathione (GSH) levels, myeloperoxidase (MPO) and superoxide dismutase (SOD) activity were measured. Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay was also performed to evaluate apoptosis.Setting: Kafkas University, Faculty of Medicine, Kars, Turkey.Results: I/R injury was successfully demonstrated with the surgical model. Betanin and copper treatment significantly decreased MDA levels, MPO activity and the number of apoptotic cells in the spinal cord. Betanin and copper treatment significantly increased GSH levels. Copper treatment significantly increased SOD activity, whereas betanin was not as effective. Apoptotic cells were significantly decreased in both treatment groups.Conclusion: I/R injury of the spinal cord can be successfully demonstrated by aortic clamping in this surgical model. Betanin/Copper sulphate has ameliorative effects against operative I/R injury. Low toxicity of those agents makes them ideal targets for clinical research for this purpose. 相似文献
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G. Coban S. Parlak E. Gumeler H. Altunbuker B. Konukan J. Karakaya B. Anlar K.K. Oguz 《AJNR. American journal of neuroradiology》2021,42(9):1709
BACKGROUND AND PURPOSE:Synthetic MRI enables the generation of various contrast-weighted images and quantitative data in a reasonable scanning time. We aimed to use synthetic MRI to assess the detection and underlying tissue characteristics of focal areas of signal intensity and normal-appearing brain parenchyma and morphometric alterations in the brains of patients with neurofibromatosis type 1.MATERIALS AND METHODS:Conventional MR imaging and synthetic MRI were prospectively obtained from 19 patients with neurofibromatosis type 1 and 18 healthy controls. Two neuroradiologists independently evaluated focal areas of signal intensity on both conventional MR imaging and synthetic MRI. Additionally, automatically segmented volume calculations of the brain in both groups and quantitative analysis of myelin, including the focal areas of signal intensity and normal-appearing brain parenchyma, of patients with neurofibromatosis type 1 were performed using synthetic MRI.RESULTS:The comparison of conventional MR imaging and synthetic MRI showed good correlation in the supratentorial region of the brain (κ = 0.82–1). Automatically segmented brain parenchymal volume, intracranial volume, and GM volumes were significantly increased in the patients with neurofibromatosis type 1 (P < .05). The myelin-correlated compound, myelin fraction volume, WM fraction volume, transverse relaxation rate, and longitudinal relaxation rate values were significantly decreased in focal areas of signal intensity on myelin and WM maps (P < .001); however, GM, GM fraction volume, and proton density values were significantly increased on the GM map (P < .001).CONCLUSIONS:Synthetic MRI is a potential tool for the assessment of morphometric and tissue alterations as well as the detection of focal areas of signal intensity in patients with neurofibromatosis type 1 in a reasonable scan time.Neuroimaging plays an important role in the diagnosis and follow-up of neurofibromatosis type 1 (NF-1). The most common parenchymal abnormality of the brain in NF-1 is oval or round focal areas of abnormal signal intensity (FASI), mainly in the basal ganglia, cerebellum, and brain stem on T2WI. These lesions do not show enhancement with gadolinium or mass effects.1 Additionally, studies in Drosophila species and mice with NF1 gene mutations have shown progressive myelin (MY) defects and behavioral abnormalities in a neurofibromin 1 dose-dependent fashion.2-4 Although evidence is inconclusive, vacuolar changes in myelin, defined as fluid-containing spaces ranging from 5 to 100 mm, have been suggested to explain the FASI.5,6The synthetic MRI (SyMRI) sequence, called quantification of relaxation times and proton density by multiecho acquisition of a saturation-recovery (QRAPMASTER) using turbo spin-echo readout,7 enables automatic segmentation of brain tissue and measurement of myelin-based quantitative values with good accuracy and reproducibility in approximately 6 minutes with full head coverage.8 This sequence has had encouraging results for brain metastasis, multiple sclerosis, meningitis, idiopathic normal pressure hydrocephalus, and Sturge-Weber syndrome in several studies and has been approved by the FDA.8-12In this study, we aimed to detect and evaluate FASI and examine morphometric changes in the brain in patients with NF-1 using SyMRI. We also sought myelin abnormalities in FASI and normal-appearing brain parenchyma (NABP) in patients with NF-1. Because FASI tends to resolve by early adulthood, we intentionally performed this study with pediatric patients.13 Our hypothesis was that SyMRI could detect FASI and quantify morphologic and tissue changes in pediatric patients with NF-1. 相似文献