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Sample records for cerebral small vessel

  1. What is cerebral small vessel disease?

    International Nuclear Information System (INIS)

    An accumulating amount of evidence suggests that the white matter hyperintensities on T2 weighted brain magnetic resonance imaging predict an increased risk of dementia and gait disturbance. This state has been proposed as cerebral small vessel disease, including leukoaraiosis, Binswanger's disease, lacunar stroke and cerebral microbleeds. However, the concept of cerebral small vessel disease is still obscure. To understand the cerebral small vessel disease, the precise structure and function of cerebral small vessels must be clarified. Cerebral small vessels include several different arteries which have different anatomical structures and functions. Important functions of the cerebral small vessels are blood-brain barrier and perivasucular drainage of interstitial fluid from the brain parenchyma. Cerebral capillaries and glial endfeet, take an important role for these functions. However, the previous pathological investigations on cerebral small vessels have focused on larger arteries than capillaries. Therefore little is known about the pathology of capillaries in small vessel disease. The recent discoveries of genes which cause the cerebral small vessel disease indicate that the cerebral small vessel diseases are caused by a distinct molecular mechanism. One of the pathological findings in hereditary cerebral small vessel disease is the loss of smooth muscle cells, which is an also well-recognized finding in sporadic cerebral small vessel disease. Since pericytes have similar character with the smooth muscle cells, the pericytes should be investigated in these disorders. In addition, the loss of smooth muscle cells may result in dysfunction of drainage of interstitial fluid from capillaries. The precise correlation between the loss of smooth muscle cells and white matter disease is still unknown. However, the function that is specific to cerebral small vessel may be associated with the pathogenesis of cerebral small vessel disease. (author)

  2. Brief cognitive assessment for patients with cerebral small vessel disease

    OpenAIRE

    O'Sullivan, M.; Morris, R; Markus, H

    2005-01-01

    Background: Cerebral small vessel disease is a common cause of cognitive impairment and vascular dementia. The cognitive deficit differs from that in Alzheimer's disease, with greater executive/attentional dysfunction and relatively intact episodic memory.

  3. Small white matter lesion detection in cerebral small vessel disease

    Science.gov (United States)

    Ghafoorian, Mohsen; Karssemeijer, Nico; van Uden, Inge; de Leeuw, Frank E.; Heskes, Tom; Marchiori, Elena; Platel, Bram

    2015-03-01

    Cerebral small vessel disease (SVD) is a common finding on magnetic resonance images of elderly people. White matter lesions (WML) are important markers for not only the small vessel disease, but also neuro-degenerative diseases including multiple sclerosis, Alzheimer's disease and vascular dementia. Volumetric measurements such as the "total lesion load", have been studied and related to these diseases. With respect to SVD we conjecture that small lesions are important, as they have been observed to grow over time and they form the majority of lesions in number. To study these small lesions they need to be annotated, which is a complex and time-consuming task. Existing (semi) automatic methods have been aimed at volumetric measurements and large lesions, and are not suitable for the detection of small lesions. In this research we established a supervised voxel classification CAD system, optimized and trained to exclusively detect small WMLs. To achieve this, several preprocessing steps were taken, which included a robust standardization of subject intensities to reduce inter-subject intensity variability as much as possible. A number of features that were found to be well identifying small lesions were calculated including multimodal intensities, tissue probabilities, several features for accurate location description, a number of second order derivative features as well as multi-scale annular filter for blobness detection. Only small lesions were used to learn the target concept via Adaboost using random forests as its basic classifiers. Finally the results were evaluated using Free-response receiver operating characteristic.

  4. Enlarged perivascular spaces and cerebral small vessel disease

    OpenAIRE

    Potter, Gillian M; Doubal, Fergus N; Jackson, Caroline A; Chappell, Francesca M; Sudlow, Cathie L; Dennis, Martin S; Wardlaw, Joanna M.

    2013-01-01

    Background and aims Enlarged perivascular spaces (also known as Virchow–Robin spaces) on T2-weighted brain magnetic resonance imaging are common, but their etiology, and specificity to small vessel as opposed to general cerebrovascular disease or ageing, is unclear. We tested the association between enlarged perivascular spaces and ischemic stroke subtype, other markers of small vessel disease, and common vascular risk factors. Methods We prospectively recruited patients with acute stroke, di...

  5. Treatment for cerebral small vessel disease: effect of relaxin on the function and structure of cerebral parenchymal arterioles during hypertension

    OpenAIRE

    Chan, Siu-Lung; Sweet, Julie G.; Cipolla, Marilyn J.

    2013-01-01

    We investigated the effect of hypertension on the function and structure of cerebral parenchymal arterioles (PAs), a major target of cerebral small vessel disease (SVD), and determined whether relaxin is a treatment for SVD during hypertension. PAs were isolated from 18-wk-old female normotensive Wistar-Kyoto (WKY) rats, spontaneous hypertensive rats (SHRs), and SHRs treated with human relaxin 2 for 14 d (4 μg/h; n=8/group) and studied using a pressurized arteriograph system. Hypertension red...

  6. Detection of white matter lesions in cerebral small vessel disease

    Science.gov (United States)

    Riad, Medhat M.; Platel, Bram; de Leeuw, Frank-Erik; Karssemeijer, Nico

    2013-02-01

    White matter lesions (WML) are diffuse white matter abnormalities commonly found in older subjects and are important indicators of stroke, multiple sclerosis, dementia and other disorders. We present an automated WML detection method and evaluate it on a dataset of small vessel disease (SVD) patients. In early SVD, small WMLs are expected to be of importance for the prediction of disease progression. Commonly used WML segmentation methods tend to ignore small WMLs and are mostly validated on the basis of total lesion load or a Dice coefficient for all detected WMLs. Therefore, in this paper, we present a method that is designed to detect individual lesions, large or small, and we validate the detection performance of our system with FROC (free-response ROC) analysis. For the automated detection, we use supervised classification making use of multimodal voxel based features from different magnetic resonance imaging (MRI) sequences, including intensities, tissue probabilities, voxel locations and distances, neighborhood textures and others. After preprocessing, including co-registration, brain extraction, bias correction, intensity normalization, and nonlinear registration, ventricle segmentation is performed and features are calculated for each brain voxel. A gentle-boost classifier is trained using these features from 50 manually annotated subjects to give each voxel a probability of being a lesion voxel. We perform ROC analysis to illustrate the benefits of using additional features to the commonly used voxel intensities; significantly increasing the area under the curve (Az) from 0.81 to 0.96 (p<0.05). We perform the FROC analysis by testing our classifier on 50 previously unseen subjects and compare the results with manual annotations performed by two experts. Using the first annotator results as our reference, the second annotator performs at a sensitivity of 0.90 with an average of 41 false positives per subject while our automated method reached the same

  7. Endothelial dysfunction is associated with the severity of cerebral small vessel disease.

    Science.gov (United States)

    Nezu, Tomohisa; Hosomi, Naohisa; Aoki, Shiro; Kubo, Satoshi; Araki, Mutsuko; Mukai, Tomoya; Takahashi, Tetsuya; Maruyama, Hirofumi; Higashi, Yukihito; Matsumoto, Masayasu

    2015-04-01

    The pathogenesis of cerebral small vessel disease, a disease that involves white matter lesions (WMLs) and cerebral microbleeds (CMBs), is thought to be associated with endothelial dysfunction. Flow-mediated dilation (FMD) has been used to measure endothelium-dependent vasodilation. The aim of this study was to investigate the association between endothelial function (as measured by FMD) and cerebral small vessel disease. Patients with a history of cerebrovascular disease and comorbidities were enrolled in this study (n=102; 69 males, 70.1±9.2 years). The patients were divided into two groups according to the severity of WMLs, which were assessed by Fazekas classification; grades 0 to 1 as mild WMLs group and grades 2 to 3 as severe WMLs group. A gradient-echo MRI was performed in 96 patients (94.1%) to evaluate whether CMBs were present. The patients in the severe WMLs group (n=40) were older (P=0.001), more frequently exhibited hypertension (P=0.045) and diabetes mellitus (P=0.026) and possessed lower FMD values (PFMD cutoff values for predicting the presence of severe WMLs and CMBs were 3.9% and 3.7%, respectively. On multivariate logistic analysis, FMD FMD dysfunction as evaluated by FMD may be predictive of the severity of cerebral small vessel disease. PMID:25672660

  8. Cerebrovascular dysfunction and microcirculation rarefaction precede white matter lesions in a mouse genetic model of cerebral ischemic small vessel disease

    OpenAIRE

    Joutel, A.; Monet-Lepretre, M.; Gosele, C.; Baron-Menguy, C.; Hammes, A.; Schmidt, S.; Lemaire-Carrette, B.; Domenga, V.; Schedl, A; Lacombe, P.; Huebner, N.

    2010-01-01

    Cerebral ischemic small vessel disease (SVD) is the leading cause of vascular dementia and a major contributor to stroke in humans. Dominant mutations in NOTCH3 cause cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a genetic archetype of cerebral ischemic SVD. Progress toward understanding the pathogenesis of this disease and developing effective therapies has been hampered by the lack of a good animal model. Here, we report the developmen...

  9. Dementia due to cerebral small vessel damage: Current ideas on its pathogenesis and therapy

    Directory of Open Access Journals (Sweden)

    I. V. Damulin

    2014-12-01

    Full Text Available Ever-increasing attention now focusses on dementia caused by small vessel damage when considering cerebrovascular disease leading to cognitive impairments (CIs. Stroke is one of the most important risk factors (RFs of vascular CI, including vascular dementia. Experienced stroke increases thrice the risk of dementia. Diffuse changes in the cerebral white matter (leukoaraiosis due to fluctuating blood pressure (BP and cerebral small vessel damage in most cases play an important role in the genesis of vascular CIs. Executive dysfunctions frequently concurrent with delayed psychomotor speed are the leading clinical manifestations of subcortical vascular dementia. Severe memory impairments are nottypical for subcortical dementia, its early stages in particular. The basis for the pathogenesis of CIs is the dissociation phenomenon that disrupts connections between the frontal lobes and subcortical structures and other cerebral cortical areas. Inadequate hypertension correction at a middle age is responsible for more than one fourth of cases of dementia developing in the elderly. The detection and further elimination of vascular RFs can reduce the risk of developing dementia in elderly and senile patients. Correction of elevated BP in the middle-aged is regarded as an effective method to prevent dementia in the future, but no premium is placed upon antihypertensive therapy in the elderly to lower elevated BP that is an inherent characteristic of this category of patients. Medications affecting RFs and those improving cerebral metabolism and bloodflow, including nicergoline are widely used to treat PD.

  10. NADPH Oxidase Activity in Cerebral Arterioles Is a Key Mediator of Cerebral Small Vessel Disease—Implications for Prevention

    Directory of Open Access Journals (Sweden)

    Mark F. McCarty

    2015-04-01

    Full Text Available Cerebral small vessel disease (SVD, a common feature of brain aging, is characterized by lacunar infarcts, microbleeds, leukoaraiosis, and a leaky blood-brain barrier. Functionally, it is associated with cognitive decline, dementia, depression, gait abnormalities, and increased risk for stroke. Cerebral arterioles in this syndrome tend to hypertrophy and lose their capacity for adaptive vasodilation. Rodent studies strongly suggest that activation of Nox2-dependent NADPH oxidase activity is a crucial driver of these structural and functional derangements of cerebral arterioles, in part owing to impairment of endothelial nitric oxide synthase (eNOS activity. This oxidative stress may also contribute to the breakdown of the blood-brain barrier seen in SVD. Hypertension, aging, metabolic syndrome, smoking, hyperglycemia, and elevated homocysteine may promote activation of NADPH oxidase in cerebral arterioles. Inhibition of NADPH oxidase with phycocyanobilin from spirulina, as well as high-dose statin therapy, may have potential for prevention and control of SVD, and high-potassium diets merit study in this regard. Measures which support effective eNOS activity in other ways—exercise training, supplemental citrulline, certain dietary flavonoids (as in cocoa and green tea, and capsaicin, may also improve the function of cerebral arterioles. Asian epidemiology suggests that increased protein intakes may decrease risk for SVD; conceivably, arginine and/or cysteine—which boosts tissue glutathione synthesis, and can be administered as N-acetylcysteine—mediate this benefit. Ameliorating the risk factors for SVD—including hypertension, metabolic syndrome, hyperglycemia, smoking, and elevated homocysteine—also may help to prevent and control this syndrome, although few clinical trials have addressed this issue to date.

  11. Alterations of the cerebral cortex in sporadic small vessel disease: A systematic review of in vivo MRI data.

    Science.gov (United States)

    Peres, Roxane; De Guio, François; Chabriat, Hugues; Jouvent, Eric

    2016-04-01

    Cerebral small vessel diseases of the brain are a major determinant of cognitive impairment in the elderly. In small vessel diseases, the most easily identifiable lesions, both at post-mortem evaluation and magnetic resonance imaging, lie in subcortical areas. However, recent results obtained post-mortem, particularly in severe cases, have highlighted the burden of cortex lesions such as microinfarcts and diffuse neuronal loss. The recent development of image post-processing methods allows now assessing in vivo multiple aspects of the cerebral cortex. This systematic review aimed to analyze in vivo magnetic resonance imaging studies evaluating cortex alterations at different stages of small vessel diseases. Studies assessing the relationships between small vessel disease magnetic resonance imaging markers obtained at the subcortical level and cortex estimates were reviewed both in community-dwelling elderly and in patients with symptomatic small vessel diseases. Thereafter, studies analyzing cortex estimates in small vessel disease patients compared with healthy subjects were evaluated. The results support that important cortex alterations develop along the course of small vessel diseases independently of concomitant neurodegenerative processes. Easy detection and quantification of cortex changes in small vessel diseases as well as understanding their underlying mechanisms are challenging tasks for better understanding cognitive decline in small vessel diseases. PMID:26787108

  12. Treatment for cerebral small vessel disease: effect of relaxin on the function and structure of cerebral parenchymal arterioles during hypertension.

    Science.gov (United States)

    Chan, Siu-Lung; Sweet, Julie G; Cipolla, Marilyn J

    2013-10-01

    We investigated the effect of hypertension on the function and structure of cerebral parenchymal arterioles (PAs), a major target of cerebral small vessel disease (SVD), and determined whether relaxin is a treatment for SVD during hypertension. PAs were isolated from 18-wk-old female normotensive Wistar-Kyoto (WKY) rats, spontaneous hypertensive rats (SHRs), and SHRs treated with human relaxin 2 for 14 d (4 μg/h; n=8/group) and studied using a pressurized arteriograph system. Hypertension reduced PA inner diameter (58±3 vs. 49±3 μm at 60 mmHg in WKY rats, Prelaxin (56±4 μm, PRelaxin also increased PA distensibility in SHRs (34±2 vs. 10±2% in SHRs, PRelaxin was detected in cerebrospinal fluid (110±30 pg/ml) after systemic administration, suggesting that it crosses the blood-brain barrier (BBB). Relaxin receptors (RXFP1/2) were not detected in cerebral vasculature, but relaxin increased vascular endothelial growth factor (VEGF) and matrix metalloproteinase 2 (MMP-2) expression in brain cortex. Inhibition of VEGF receptor tyrosine kinase (axitinib, 4 mg/kg/d, 14 d) had no effect on increased distensibility with relaxin, but caused outward hypertrophic remodeling of PAs from SHRs. These results suggest that relaxin crosses the BBB and activates MMP-2 in brain cortex, which may interact with PAs to increase distensibility. VEGF appears to be involved in remodeling of PAs, but not relaxin-induced increased distensibility. PMID:23783073

  13. Association between Serum Alkaline Phosphatase Level and Cerebral Small Vessel Disease.

    Directory of Open Access Journals (Sweden)

    Han-Bin Lee

    Full Text Available Serum alkaline phosphatase (ALP is a marker of vascular calcification. A high serum ALP level is associated with an increase in cardiovascular events, and predicts poor functional outcome in patients with stroke. We investigated whether serum ALP was associated with cerebral small vessel disease (cSVD and large cerebral artery stenosis (LCAS.We evaluated vascular risk factors, brain magnetic resonance images (MRIs, and MR angiograms from 1,011 neurologically healthy participants. The presence of silent lacunar infarction (SLI and moderate-to-severe cerebral white matter hyperintensities (MS-cWMH were evaluated as indices of cSVD on brain MRIs. Findings of extracranial arterial stenosis (ECAS or intracranial arterial stenosis (ICAS were considered to be indices of LCAS on MR angiograms.Subjects with SLI (odds ratio [OR]: 2.09; 95% confidence interval [CI]: 1.27-3.42; p = 0.004 and MS-cWMH (OR: 1.48; 95% CI; 1.03-2.13, p = 0.036 were significantly more likely to have ALP levels in the third tertile (ALP ≥ 195 IU/L than the first tertile (ALP ≤ 155 IU/L, after adjusting for cardiovascular risk factors. The mean serum ALP level was significantly higher in patients with SLI or MS-cWMH compared to patients without those findings. After adjustment for confounding factors, the multivariate model found that the statistical significance of serum ALP remained when the presence of SLI (OR: 1.05 per 10 IU/L increase in ALP; 95% CI: 1.02-1.08; p = 0.003 or MS-cWMH (OR: 1.03 per 10 IU/L increase in ALP; 95% CI: 1.00-1.06; p = 0.025 were added to the model. There were no differences in the proportions of patients with LCAS, ICAS, and ECAS across the serum ALP tertiles.Our study of neurologically healthy participants found a positive association between serum ALP level and indicators of cSVD, but no association between serum ALP level and the indicators of LCAS.

  14. Novel COL4A1 mutations cause cerebral small vessel disease by haploinsufficiency

    Science.gov (United States)

    Lemmens, Robin; Maugeri, Alessandra; Niessen, Hans W. M.; Goris, An; Tousseyn, Thomas; Demaerel, Philippe; Corveleyn, Anniek; Robberecht, Wim; van der Knaap, Marjo S.; Thijs, Vincent N.; Zwijnenburg, Petra J.G.

    2013-01-01

    Mutations in COL4A1 have been identified in families with hereditary small vessel disease of the brain presumably due to a dominant-negative mechanism. Here, we report on two novel mutations in COL4A1 in two families with porencephaly, intracerebral hemorrhage and severe white matter disease caused by haploinsufficiency. Two families with various clinical presentations of cerebral microangiopathy and autosomal dominant inheritance were examined. Clinical, neuroradiological and genetic investigations were performed. Electron microscopy of the skin was also performed. In one of the families, sequence analysis revealed a one base deletion, c.2085del, leading to a frameshift and a premature stopcodon, p.(Gly696fs). In the other family, a splice site mutation was identified, c.2194-1G>A, which most likely leads to skipping of an exon with a frameshift and premature termination as a result. In fibroblasts of affected individuals from both the families, nonsense-mediated decay (NMD) of the mutant COL4A1 messenger RNAs (mRNAs) and a clear reduction of COL4A1 protein expression were demonstrated, indicating haploinsufficiency of COL4A1. Moreover, thickening of the capillary basement membrane in the skin was documented, similar to reports in patients with COL4A1 missense mutations. These findings suggest haploinsufficiency, a different mechanism from the commonly assumed dominant-negative effect, for COL4A1 mutations as a cause of (antenatal) intracerebral hemorrhage and white matter disease. PMID:23065703

  15. Cerebral small vessel disease affects white matter microstructure in mild cognitive impairment.

    Science.gov (United States)

    Papma, Janne M; de Groot, Marius; de Koning, Inge; Mattace-Raso, Francesco U; van der Lugt, Aad; Vernooij, Meike W; Niessen, Wiro J; van Swieten, John C; Koudstaal, Peter J; Prins, Niels D; Smits, Marion

    2014-06-01

    Microstructural white matter deterioration is a frequent finding in mild cognitive impairment (MCI), potentially underlying default mode network (DMN) dysfunctioning. Thus far, microstructural damage in MCI has been attributed to Alzheimer's disease pathophysiology. A cerebrovascular role, in particular the role of cerebral small vessel disease (CSVD), received less interest. Here, we used diffusion tensor imaging (DTI) to examine the role of CSVD in microstructural deterioration within the normal appearing white matter (NAWM) in MCI. MCI patients were subdivided into those with (n = 20) and without (n = 31) macrostructural CSVD evidence on MRI. Using TBSS we performed microstructural integrity comparisons within the whole brain NAWM. Secondly, we segmented white matter tracts interconnecting DMN brain regions by means of automated tractography segmentation. We used NAWM DTI measures from these tracts as dependent variables in a stepwise-linear regression analysis, with structural and demographical predictors. Our results indicated microstructural deterioration within the anterior corpus callosum, internal and external capsule and periventricular white matter in MCI patients with CSVD, while in MCI patients without CSVD, deterioration was restricted to the right perforant path, a tract along the hippocampus. Within the full cohort of MCI patients, microstructure within the NAWM of the DMN fiber tracts was affected by the presence of CSVD. Within the cingulum along the hippocampal cortex we found a relationship between microstructural integrity and ipsilateral hippocampal volume and the extent of white matter hyperintensity. In conclusion, we found evidence of CSVD-related microstructural damage in fiber tracts subserving the DMN in MCI. PMID:24115179

  16. New angiographic measurement tool for analysis of small cerebral vessels: application to a subarachnoid haemorrhage model in the rat

    International Nuclear Information System (INIS)

    Exact quantification of vasospasm by angiography is known to be difficult especially in small vessels. The purpose of the study was to develop a new method for computerized analysis of small arteries and to demonstrate feasibility on cerebral angiographies of rats acquired on a clinical angiography unit. A new software tool analysing grey values and subtracting background noise was validated on a vessel model. It was tested in practice in animals with subarachnoid haemorrhage (SAH). A total of 28 rats were divided into four groups: SAH untreated, SAH treated with local calcium antagonist, SAH treated with placebo, and sham-operated. The diameters of segments of the internal carotid, caudal cerebral, middle cerebral, rostral cerebral and the stapedial arteries were measured and compared to direct measurements of the diameters on magnified images. There was a direct correlation between the cross-sectional area of vessels measured in a phantom and the measurements acquired using the new image analysis method. The spread of repeated measurements with the new software was small compared to the spread of direct measurements of vessel diameters on magnified images. Application of the measurement tool to experimental SAH in rats showed a statistically significant reduction of vasospasm in the SAH groups treated with nimodipine-releasing pellets in comparison to all the other groups combined. The presented computerized method for analysis of small intracranial vessels is a new method allowing precise relative measurements. Nimodipine-releasing subarachnoidal pellets reduce vasospasm, but further testing with larger numbers is necessary. The tool can be applied to human angiography without modification and offers the promise of substantial progress in the diagnosis of vasospasm after SAH. (orig.)

  17. Association of Chronic Kidney Disease and Cerebral Small Vessel Disease with Cognitive Impairment in Elderly Patients with Type 2 Diabetes

    OpenAIRE

    Umemura, Toshitaka; Kawamura, Takahiko; Umegaki, Hiroyuki; Kawano, Naoko; Mashita, Shinichi; Sakakibara, Toshimasa; Hotta, Nigishi; Sobue, Gen

    2013-01-01

    Background/Aims In recent years, the relationship between chronic kidney disease (CKD) and cognitive impairment has been attracting attention. Cerebral small vessel disease (SVD) is also associated with an increased risk of cognitive impairment. However, it is still unknown whether CKD markers are associated with cognitive impairment independently of SVD in elderly diabetic patients. Methods Seventy-nine type 2 diabetic patients (mean age, 76.0 years) were enrolled in the present study. CKD w...

  18. Role of thalamic diffusion for disease differentiation between multiple sclerosis and ischemic cerebral small vessel disease

    Energy Technology Data Exchange (ETDEWEB)

    Oeztoprak, Bilge; Oeztoprak, Ibrahim; Salk, Ismail [Cumhuriyet University School of Medicine, Department of Radiology, Sivas (Turkey); Topalkara, Kamil [Bayindir Hospital, Department of Neurology, Ankara (Turkey); Erkoc, Mustafa F. [Bozok University School of Medicine, Department of Radiology, Yozgat (Turkey)

    2015-04-01

    Cerebral small vessel disease (CSVD) and multiple sclerosis (MS) both harbor multiple, T2-hyperintense white matter lesions on conventional magnetic resonance imaging (MRI).We aimed to determine the microstructural changes via diffusion-weighted imaging (DWI) in normal appearing thalami. We hypothesized that the apparent diffusion coefficient (ADC) values would be different in CSVD and MS, since the extent of arterial involvement is different in these two diseases. DWI was performed for 50 patients with CSVD and 35 patients with MS along with gender- and age-matched controls whose conventional MRI revealed normal findings. DWI was done with 1.5 Tesla MR devices using echo planar imaging (EPI) for b = 0, 1000 s/mm{sup 2}. ADC values were obtained from the thalami which appeared normal on T2-weighted and FLAIR images. Standard oval regions of interest (ROIs) of 0.5 cm{sup 2} which were oriented parallel to the long axis of the thalamus were used for this purpose. The mean ADC value of the thalamus was (0.99 ± 0.16) x 10{sup -3} mm{sup 2}/s in patients with CSVD, whereas the mean ADC value was (0.78 ± 0.06) x 10{sup -3} mm{sup 2}/s in the control group. The mean ADC value was significantly higher in patients with CSVD compared to the controls (p < 0.001). The mean ADC values of the thalamus were (0.78 ± 0.08) x 10{sup -3} mm{sup 2}/s in MS patients, and (0.75 ± 0.08) x 10{sup -3} mm{sup 2}/s in the control group, which are not significantly different (p > 0.05). Our study revealed a difference in the diffusion of the thalami between CSVD and MS. DWI may aid in the radiological disease differentiation. (orig.)

  19. Role of thalamic diffusion for disease differentiation between multiple sclerosis and ischemic cerebral small vessel disease

    International Nuclear Information System (INIS)

    Cerebral small vessel disease (CSVD) and multiple sclerosis (MS) both harbor multiple, T2-hyperintense white matter lesions on conventional magnetic resonance imaging (MRI).We aimed to determine the microstructural changes via diffusion-weighted imaging (DWI) in normal appearing thalami. We hypothesized that the apparent diffusion coefficient (ADC) values would be different in CSVD and MS, since the extent of arterial involvement is different in these two diseases. DWI was performed for 50 patients with CSVD and 35 patients with MS along with gender- and age-matched controls whose conventional MRI revealed normal findings. DWI was done with 1.5 Tesla MR devices using echo planar imaging (EPI) for b = 0, 1000 s/mm2. ADC values were obtained from the thalami which appeared normal on T2-weighted and FLAIR images. Standard oval regions of interest (ROIs) of 0.5 cm2 which were oriented parallel to the long axis of the thalamus were used for this purpose. The mean ADC value of the thalamus was (0.99 ± 0.16) x 10-3 mm2/s in patients with CSVD, whereas the mean ADC value was (0.78 ± 0.06) x 10-3 mm2/s in the control group. The mean ADC value was significantly higher in patients with CSVD compared to the controls (p < 0.001). The mean ADC values of the thalamus were (0.78 ± 0.08) x 10-3 mm2/s in MS patients, and (0.75 ± 0.08) x 10-3 mm2/s in the control group, which are not significantly different (p > 0.05). Our study revealed a difference in the diffusion of the thalami between CSVD and MS. DWI may aid in the radiological disease differentiation. (orig.)

  20. Pattern and Rate of Cognitive Decline in Cerebral Small Vessel Disease: A Prospective Study.

    Directory of Open Access Journals (Sweden)

    Andrew J Lawrence

    Full Text Available Cognitive impairment, predominantly affecting processing speed and executive function, is an important consequence of cerebral small vessel disease (SVD. To date, few longitudinal studies of cognition in SVD have been conducted. We determined the pattern and rate of cognitive decline in SVD and used the results to determine sample size calculations for clinical trials of interventions reducing cognitive decline.121 patients with MRI confirmed lacunar stroke and leukoaraiosis were enrolled into the prospective St George's Cognition And Neuroimaging in Stroke (SCANS study. Patients attended one baseline and three annual cognitive assessments providing 36 month follow-up data. Neuropsychological assessment comprised a battery of tests assessing working memory, long-term (episodic memory, processing speed and executive function. We calculated annualized change in cognition for the 98 patients who completed at least two time-points.Task performance was heterogeneous, but significant cognitive decline was found for the executive function index (p<0.007. Working memory and processing speed decreased numerically, but not significantly. The executive function composite score would require the smallest samples sizes for a treatment trial with an aim of halting decline, but this would still require over 2,000 patients per arm to detect a 30% difference with power of 0.8 over a three year follow-up.The pattern of cognitive decline seen in SVD over three years is consistent with the pattern of impairments at baseline. Rates of decline were slow and sample sizes would need to be large for clinical trials aimed at halting decline beyond initial diagnosis using cognitive scores as an outcome measure. This emphasizes the importance of more sensitive surrogate markers in this disease.

  1. Clinical and magnetic resonance observations in cerebral small-vessel disease

    NARCIS (Netherlands)

    V.I.H. Kwa

    1999-01-01

    The study reported in this thesis tried to address the following questions: 1. Is it possible to detect genetic factors and vascular risk factors that are specifically associated with the development of small- or large-vessel disease? 2. Are the different clinical and MRI manifestations, that are at

  2. Associations between arterial stiffness, depressive symptoms and cerebral small vessel disease: cross-sectional findings from the AGES-Reykjavik Study

    Science.gov (United States)

    van Sloten, Thomas T.; Mitchell, Gary F.; Sigurdsson, Sigurdur; van Buchem, Mark A.; Jonsson, Palmi V.; Garcia, Melissa E.; Harris, Tamara B.; Henry, Ronald M.A.; Levey, Andrew S.; Stehouwer, Coen D.A.; Gudnason, Vilmundur; Launer, Lenore J.

    2016-01-01

    Background Arterial stiffness may contribute to depression via cerebral microvascular damage, but evidence for this is scarce. We therefore investigated whether arterial stiffness is associated with depressive symptoms and whether cerebral small vessel disease contributes to this association. Methods This cross-sectional study included a subset of participants from the AGES-Reykjavik study second examination round, which was conducted from 2007 to 2011. Arterial stiffness (carotid–femoral pulse wave velocity [CFPWV]), depressive symptoms (15-item geriatric depression scale [GDS-15]) and cerebral small vessel disease (MRI) were determined. Manifestations of cerebral small vessel disease included higher white matter hyperintensity volume, subcortical infarcts, cerebral microbleeds, Virchow–Robin spaces and lower total brain parenchyma volume. Results We included 2058 participants (mean age 79.6 yr; 59.0% women) in our analyses. Higher CFPWV was associated with a higher GDS-15 score, after adjustment for potential confounders (β 0.096, 95% confidence interval [CI] 0.005–0.187). Additional adjustment for white matter hyperintensity volume or subcortical infarcts attenuated the association between CFPWV and the GDS-15 score, which became nonsignificant (p > 0.05). Formal mediation tests showed that the attenuating effects of white matter hyperintensity volume and subcortical infarcts were statistically significant. Virchow–Robin spaces, cerebral microbleeds and cerebral atrophy did not explain the association between CFPWV and depressive symptoms. Limitations Our study was limited by its cross-sectional design, which precludes any conclusions about causal mediation. Depressive symptoms were assessed by a self-report questionnaire. Conclusion Greater arterial stiffness is associated with more depressive symptoms; this association is partly accounted for by white matter hyperintensity volume and subcortical infarcts. This study supports the hypothesis that

  3. Vitamin D status and vascular dementia due to cerebral small vessel disease in the elderly Asian Indian population.

    Science.gov (United States)

    Prabhakar, Puttachandra; Chandra, Sadanandavalli Retnaswami; Supriya, Manjunath; Issac, Thomas Gregor; Prasad, Chandrajit; Christopher, Rita

    2015-12-15

    Vitamin D plays vital roles in human health and recent studies have shown its beneficial effect on brain functioning. The present study was designed to evaluate the association of vitamin D with vascular dementia (VaD) due to cerebral small vessel disease (SVD) in Asian Indian population. 140 VaD patients aged ≥ 60 years with neuroimaging evidence of SVD, and 132 age and gender-matched controls, were investigated. Vitamin D status was estimated by measuring serum 25-hydroxy vitamin D. Logistic regression model revealed that deficient levels of vitamin D (vitamin D deficiency and insufficiency (12-20 ng/ml), the odds were increased to 31.6-fold and 14.4-fold, respectively. However, in hypertensives with vitamin D sufficiency (>20 ng/ml), the odds of VaD were increased by 3.8-fold only. Pearson correlation showed that serum vitamin D was inversely associated with systolic and diastolic blood pressure (r=-0.401 and -0.411, pvitamin D-deficient subjects. Since the combined presence of hypertension and vitamin D deficiency increases the probability of developing VaD, screening for vitamin D status in addition to regular monitoring of blood pressure, could reduce the risk of VaD associated with cerebral SVD in the elderly Asian Indian subjects. PMID:26671097

  4. Causes and consequences of cerebral small vessel disease. The RUN DMC study: a prospective cohort study. Study rationale and protocol

    Directory of Open Access Journals (Sweden)

    van der Vlugt Maureen J

    2011-02-01

    Full Text Available Abstract Background Cerebral small vessel disease (SVD is a frequent finding on CT and MRI scans of elderly people and is related to vascular risk factors and cognitive and motor impairment, ultimately leading to dementia or parkinsonism in some. In general, the relations are weak, and not all subjects with SVD become demented or get parkinsonism. This might be explained by the diversity of underlying pathology of both white matter lesions (WML and the normal appearing white matter (NAWM. Both cannot be properly appreciated with conventional MRI. Diffusion tensor imaging (DTI provides alternative information on microstructural white matter integrity. The association between SVD, its microstructural integrity, and incident dementia and parkinsonism has never been investigated. Methods/Design The RUN DMC study is a prospective cohort study on the risk factors and cognitive and motor consequences of brain changes among 503 non-demented elderly, aged between 50-85 years, with cerebral SVD. First follow up is being prepared for July 2011. Participants alive will be included and invited to the research centre to undergo a structured questionnaire on demographics and vascular risk factors, and a cognitive, and motor, assessment, followed by a MRI protocol including conventional MRI, DTI and resting state fMRI. Discussion The follow up of the RUN DMC study has the potential to further unravel the causes and possibly better predict the consequences of changes in white matter integrity in elderly with SVD by using relatively new imaging techniques. When proven, these changes might function as a surrogate endpoint for cognitive and motor function in future therapeutic trials. Our data could furthermore provide a better understanding of the pathophysiology of cognitive and motor disturbances in elderly with SVD. The execution and completion of the follow up of our study might ultimately unravel the role of SVD on the microstructural integrity of the white

  5. Application of Diffusion Tensor Imaging Parameters to Detect Change in Longitudinal Studies in Cerebral Small Vessel Disease.

    Science.gov (United States)

    Zeestraten, Eva Anna; Benjamin, Philip; Lambert, Christian; Lawrence, Andrew John; Williams, Owen Alan; Morris, Robin Guy; Barrick, Thomas Richard; Markus, Hugh Stephen

    2016-01-01

    Cerebral small vessel disease (SVD) is the major cause of vascular cognitive impairment, resulting in significant disability and reduced quality of life. Cognitive tests have been shown to be insensitive to change in longitudinal studies and, therefore, sensitive surrogate markers are needed to monitor disease progression and assess treatment effects in clinical trials. Diffusion tensor imaging (DTI) is thought to offer great potential in this regard. Sensitivity of the various parameters that can be derived from DTI is however unknown. We aimed to evaluate the differential sensitivity of DTI markers to detect SVD progression, and to estimate sample sizes required to assess therapeutic interventions aimed at halting decline based on DTI data. We investigated 99 patients with symptomatic SVD, defined as clinical lacunar syndrome with MRI confirmation of a corresponding infarct as well as confluent white matter hyperintensities over a 3 year follow-up period. We evaluated change in DTI histogram parameters using linear mixed effect models and calculated sample size estimates. Over a three-year follow-up period we observed a decline in fractional anisotropy and increase in diffusivity in white matter tissue and most parameters changed significantly. Mean diffusivity peak height was the most sensitive marker for SVD progression as it had the smallest sample size estimate. This suggests disease progression can be monitored sensitively using DTI histogram analysis and confirms DTI's potential as surrogate marker for SVD. PMID:26808982

  6. Association of Chronic Kidney Disease and Cerebral Small Vessel Disease with Cognitive Impairment in Elderly Patients with Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Toshitaka Umemura

    2013-07-01

    Full Text Available Background/Aims: In recent years, the relationship between chronic kidney disease (CKD and cognitive impairment has been attracting attention. Cerebral small vessel disease (SVD is also associated with an increased risk of cognitive impairment. However, it is still unknown whether CKD markers are associated with cognitive impairment independently of SVD in elderly diabetic patients. Methods: Seventy-nine type 2 diabetic patients (mean age, 76.0 years were enrolled in the present study. CKD was defined as the presence of albuminuria and/or a low estimated glomerular filtration rate (eGFR 2. SVD was evaluated by the presence and severity of silent brain infarcts (SBIs and white matter lesions (WMLs on brain magnetic resonance imaging. Neuropsychological tests were assessed using four validated cognitive instruments. Results: In multiple linear regression analyses, albuminuria was associated with worse modified Stroop Color Word scores (β = 0.284, p = 0.017 and low eGFR was associated with reduced Digit Symbol Substitution scores (β = -0.224, p = 0.026 after adjustment for age, sex, education years, diabetes duration, hypertension, multiple SBIs, and advanced WMLs. In contrast, there were no significant associations between CKD markers and Mini-Mental State Examination or Word Recall scores. Conclusion: Our findings suggest that albuminuria and low eGFR are associated with frontal lobe dysfunction independently of SVD in elderly type 2 diabetic patients.

  7. Association of Aortic Compliance and Brachial Endothelial Function with Cerebral Small Vessel Disease in Type 2 Diabetes Mellitus Patients: Assessment with High-Resolution MRI

    Science.gov (United States)

    Shan, Yan; Zeng, Mengsu; Lin, Huandong; Yan, Hongmei

    2016-01-01

    Objective. To assess the possible association of aortic compliance and brachial endothelial function with cerebral small vessel disease in type 2 diabetes mellitus (DM2) patients by using 3.0 T high-resolution magnetic resonance imaging. Methods. Sixty-two clinically confirmed DM2 patients (25 women and 37 men; mean age: 56.8 ± 7.5 years) were prospectively enrolled for noninvasive MR examinations of the aorta, brachial artery, and brain. Aortic arch pulse wave velocity (PWV), flow-mediated dilation (FMD) of brachial artery, lacunar brain infarcts, and periventricular and deep white matter hyperintensities (WMHs) were assessed. Pearson and Spearman correlation analysis were performed to analyze the association between PWV and FMD with clinical data and biochemical test results. Univariable logistic regression analyses were used to analyze the association between PWV and FMD with cerebral small vessel disease. Multiple logistic regression analyses were used to find out the independent predictive factors of cerebral small vessel disease. Results. Mean PWV was 6.73 ± 2.00 m/s and FMD was 16.67 ± 9.11%. After adjustment for compounding factors, PWV was found significantly associated with lacunar brain infarcts (OR = 2.00; 95% CI: 1.14–3.2; P < 0.05) and FMD was significantly associated with periventricular WMHs (OR = 0.82; 95% CI: 0.71–0.95; P < 0.05). Conclusions. Quantitative evaluation of aortic compliance and endothelial function by using high-resolution MRI may be potentially useful to stratify DM2 patients with risk of cerebral small vessel disease. PMID:27525261

  8. Association of Aortic Compliance and Brachial Endothelial Function with Cerebral Small Vessel Disease in Type 2 Diabetes Mellitus Patients: Assessment with High-Resolution MRI.

    Science.gov (United States)

    Shan, Yan; Lin, Jiang; Xu, Pengju; Zeng, Mengsu; Lin, Huandong; Yan, Hongmei

    2016-01-01

    Objective. To assess the possible association of aortic compliance and brachial endothelial function with cerebral small vessel disease in type 2 diabetes mellitus (DM2) patients by using 3.0 T high-resolution magnetic resonance imaging. Methods. Sixty-two clinically confirmed DM2 patients (25 women and 37 men; mean age: 56.8 ± 7.5 years) were prospectively enrolled for noninvasive MR examinations of the aorta, brachial artery, and brain. Aortic arch pulse wave velocity (PWV), flow-mediated dilation (FMD) of brachial artery, lacunar brain infarcts, and periventricular and deep white matter hyperintensities (WMHs) were assessed. Pearson and Spearman correlation analysis were performed to analyze the association between PWV and FMD with clinical data and biochemical test results. Univariable logistic regression analyses were used to analyze the association between PWV and FMD with cerebral small vessel disease. Multiple logistic regression analyses were used to find out the independent predictive factors of cerebral small vessel disease. Results. Mean PWV was 6.73 ± 2.00 m/s and FMD was 16.67 ± 9.11%. After adjustment for compounding factors, PWV was found significantly associated with lacunar brain infarcts (OR = 2.00; 95% CI: 1.14-3.2; P < 0.05) and FMD was significantly associated with periventricular WMHs (OR = 0.82; 95% CI: 0.71-0.95; P < 0.05). Conclusions. Quantitative evaluation of aortic compliance and endothelial function by using high-resolution MRI may be potentially useful to stratify DM2 patients with risk of cerebral small vessel disease. PMID:27525261

  9. Aortic stiffness is associated with cardiac function and cerebral small vessel disease in patients with type 1 diabetes mellitus: assessment by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Elderen, Saskia G.C. van; Brandts, A.; Westenberg, J.J.M.; Grond, J. van der; Buchem, M.A. van; Kroft, L.J.M.; Roos, A. de [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Tamsma, J.T.; Romijn, J.A.; Smit, J.W.A. [Leiden University Medical Center, Department of Endocrinology, Leiden (Netherlands)

    2010-05-15

    To evaluate, with the use of magnetic resonance imaging (MRI), whether aortic pulse wave velocity (PWV) is associated with cardiac left ventricular (LV) function and mass as well as with cerebral small vessel disease in patients with type 1 diabetes mellitus (DM). We included 86 consecutive type 1 DM patients (49 male, mean age 46.9 {+-} 11.7 years) in a prospective, cross-sectional study. Exclusion criteria included aortic/heart disease and general MRI contra-indications. MRI of the aorta, heart and brain was performed for assessment of aortic PWV, as a marker of aortic stiffness, systolic LV function and mass, as well as for the presence of cerebral white matter hyperintensities (WMHs), microbleeds and lacunar infarcts. Multivariate linear or logistic regression was performed to analyse the association between aortic PWV and outcome parameters, with covariates defined as age, gender, mean arterial pressure, heart rate, BMI, smoking, DM duration and hypertension. Mean aortic PWV was 7.1 {+-} 2.5 m/s. Aortic PWV was independently associated with LV ejection fraction (ss= -0.406, P = 0.006), LV stroke volume (ss=-0.407, P = 0.001), LV cardiac output (ss= -0.458, P = 0.001), and with cerebral WMHs (P < 0.05). There were no independent associations between aortic stiffness and LV mass, cerebral microbleeds or lacunar infarcts. Aortic stiffness is independently associated with systolic LV function and cerebral WMHs in patients with type 1 DM. (orig.)

  10. Aortic stiffness is associated with cardiac function and cerebral small vessel disease in patients with type 1 diabetes mellitus: assessment by magnetic resonance imaging

    International Nuclear Information System (INIS)

    To evaluate, with the use of magnetic resonance imaging (MRI), whether aortic pulse wave velocity (PWV) is associated with cardiac left ventricular (LV) function and mass as well as with cerebral small vessel disease in patients with type 1 diabetes mellitus (DM). We included 86 consecutive type 1 DM patients (49 male, mean age 46.9 ± 11.7 years) in a prospective, cross-sectional study. Exclusion criteria included aortic/heart disease and general MRI contra-indications. MRI of the aorta, heart and brain was performed for assessment of aortic PWV, as a marker of aortic stiffness, systolic LV function and mass, as well as for the presence of cerebral white matter hyperintensities (WMHs), microbleeds and lacunar infarcts. Multivariate linear or logistic regression was performed to analyse the association between aortic PWV and outcome parameters, with covariates defined as age, gender, mean arterial pressure, heart rate, BMI, smoking, DM duration and hypertension. Mean aortic PWV was 7.1 ± 2.5 m/s. Aortic PWV was independently associated with LV ejection fraction (ss= -0.406, P = 0.006), LV stroke volume (ss=-0.407, P = 0.001), LV cardiac output (ss= -0.458, P = 0.001), and with cerebral WMHs (P < 0.05). There were no independent associations between aortic stiffness and LV mass, cerebral microbleeds or lacunar infarcts. Aortic stiffness is independently associated with systolic LV function and cerebral WMHs in patients with type 1 DM. (orig.)

  11. Cerebral large vessel vasculitis in systemic lupus erythematosus.

    Science.gov (United States)

    Böckle, B C; Jara, D; Aichhorn, K; Junker, D; Berger, T; Ratzinger, G; Sepp, N T

    2014-11-01

    Neuropsychiatric systemic lupus erythematosus (NPSLE) is defined by involvement of the central nervous system in systemic lupus erythematosus (SLE), with a wide range of both neurological and psychiatric manifestations. Although its aetiopathogenesis is not fully elucidated, NPSLE seems to be a consequence of cerebral vascular pathology including thromboembolism, small-vessel vasculopathy and, in rare cases, true vasculitis. Cerebral vasculitis is rare, and cerebral large-vessel vasculitis in SLE is even more unusual. We report the case of a female patient with the diagnosis of SLE. She presented with stroke-like symptoms, headache and vertigo, and palpable purpura on her legs. Further investigations revealed that she suffered from both vasculitis of the cerebral large vessels and coexisting cutaneous small-vessel vasculitis. PMID:24969082

  12. Cerebral Small Vessel Disease and Risk of Death, Ischemic Stroke, and Cardiac Complications in Patients With Atherosclerotic Disease The Second Manifestations of ARTerial disease-Magnetic Resonance (SMART-MR) Study

    NARCIS (Netherlands)

    M.M.A. Conijn; R.P. Kloppenborg; A. Algra; W.P.T.M. Mali; L.J. Kappelle; K.L. Vincken; Y. van der Graaf; M.I. Geerlings

    2011-01-01

    Background and Purpose-Cerebral small vessel disease may be related to vascular and nonvascular pathology. We assessed whether lacunar infarcts and white matter lesions on MRI increased the risk of vascular and nonvascular death and future vascular events in patients with atherosclerotic disease. Me

  13. Accumulation of MRI markers of cerebral small vessel disease is associated with decreased cognitive function. A study in first-ever lacunar stroke and hypertensive patients.

    Directory of Open Access Journals (Sweden)

    Marjolein Huijts

    2013-11-01

    Full Text Available Background – White matter lesions (WMLs, asymptomatic lacunar infarcts, brain microbleeds (BMBs and enlarged perivascular spaces (EPVS have been identified as silent lesions due to cerebral small vessel disease (cSVD. All these markers have been individually linked to cognitive functioning, but are also strongly correlated with each other. The combined effect of these markers on cognitive function has never been studied and would possibly provide more useful information on the effect on cognitive function. Methods – Brain MRI and extensive neuropsychological assessment were performed in 189 patients at risk for cSVD (112 hypertensive patients and 77 first-ever lacunar stroke patients. We rated the presence of any asymptomatic lacunar infarct, extensive WMLs, any deep BMB, and moderate to extensive EPVS in the basal ganglia. The presence of each marker was summed to an ordinal score between 0 and 4. Associations with domains of cognitive function (memory, executive function, information processing speed and overall cognition were analyzed with correlation analyses. Results – Correlation analyses revealed significant associations between accumulating cSVD burden and decreased performance on all cognitive domains (all p≤.001. Results remained significant for information processing speed (r=-.181, p=.013 and overall cognition (r=-.178, p=.017, after correction for age and sex. Testing of trend using linear regression analyses revealed the same results. Discussion – We tested a new approach to capture total brain damage resulting from cSVD and found that accumulation of MRI burden of cSVD is associated with decreased performance on tests of information processing speed and overall cognition, implying that accumulating brain damage is accompanied by worse cognitive functioning.

  14. Digital subtraction angiography of the cerebral vessels by intraarterial injection

    International Nuclear Information System (INIS)

    Three hundred and fifty-seven digital subtraction angiography (DSA) were performed in 184 neurosurgical patients by intraarterial injection. Examinations consisted of 192 carotid angiography, 110 vertebral angiography, 23 aortography, 11 spinal angiography and 21 other angiography. In all examinations, visualization of the vessels was excellent and the complications were never experienced. High contrast sensitivity of DSA resulted in better visualization of tumor stains, phlebogram, and arteries in cerebral arteriovenous malformations with large shunt blood flow than conventional angiography. Selective catheterization into each cerebral arteries was not necessarily demanded for good opacification of the vessels because of high sensitivity. High contrast sensitivity also permitted low concentration of contrast material, small dose of contrast material, and slow injection rate. Low concentration of contrast material reduced pain and heat during injection especially in the external carotid and vertebral angiography. Using slow injection, recoiling of catheter into the aorta was reduced, so that injection from the innominate and subclavian arteries for visualization of origin of the cerebral arteries were always successful. Full study of cerebral arteries by Seldinger's method, if necessary, was easily achieved using DSA even in patient with high age or with severe atherosclerosis. Bolus injection of small dose of contrast material as well as serial imaging was helpful in evaluating hemodynamics in the lesion. Real time display of DSA reduced the time required for angiography and was very convenient for artificial embolization. Besides these advantages, DSA became comparable to conventional angiography in spacial resolution by use of intraarterial injection and could be a preoperative genuine examination as well as a screening method. (author)

  15. Evolving Concept of Small Vessel Disease through Advanced Brain Imaging.

    OpenAIRE

    Norrving, Bo

    2015-01-01

    Imaging plays a crucial role in studying and understanding cerebral small vessel disease. Several important findings have emerged from recent applications of advanced brain imaging methods. In patients with acute lacunar syndromes, diffusionweighted MRI studies have shown that the diagnostic precision of using clinical features alone or combined with CT scan findings to diagnose small vessel disease as the underlying cause is poor. Followup imaging studies on patients with acute infarcts rela...

  16. Management of Small Vessel Vasculitides.

    Science.gov (United States)

    Lopalco, Giuseppe; Rigante, Donato; Venerito, Vincenzo; Emmi, Giacomo; Anelli, Maria Grazia; Lapadula, Giovanni; Iannone, Florenzo; Cantarini, Luca

    2016-06-01

    Inflammation mediated by cells of the immune system and necrosis are the most striking features observed at the histologic level in patients with vasculitides, clinical entities classified according to pathologic findings involving different organs, to etiology, or to size of vessels involved. Small vessel vasculitides (SVV) are a peculiar group of systemic disorders electively involving small intraparenchymal arteries, arterioles, capillaries, or venules and leading to different levels of vascular obstruction, tissue ischemia and risk of infarction; they can be divided into anti-neutrophil cytoplasmic antibody-associated vasculitides and immune complex vasculitides. Despite the significant advances in understanding the whole disease process and pathophysiology of SVV, strong efforts are still needed to draft, share and spread guidelines in the therapeutic management of these protean disorders. After an accurate evaluation of different open or double-blind trials and cohort studies in this review, we analyze the actual medical tools suggested for treating granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis, Henoch-Schönlein purpura, cryoglobulinemic vasculitis, anti-glomerular basement membrane disease and hypocomplementemic urticarial vasculitis. PMID:27118389

  17. Relaxation oscillation model of hemodynamic parameters in the cerebral vessels

    Science.gov (United States)

    Cherevko, A. A.; Mikhaylova, A. V.; Chupakhin, A. P.; Ufimtseva, I. V.; Krivoshapkin, A. L.; Orlov, K. Yu

    2016-06-01

    Simulation of a blood flow under normality as well as under pathology is extremely complex problem of great current interest both from the point of view of fundamental hydrodynamics, and for medical applications. This paper proposes a model of Van der Pol - Duffing nonlinear oscillator equation describing relaxation oscillations of a blood flow in the cerebral vessels. The model is based on the patient-specific clinical experimental data flow obtained during the neurosurgical operations in Meshalkin Novosibirsk Research Institute of Circulation Pathology. The stability of the model is demonstrated through the variations of initial data and coefficients. It is universal and describes pressure and velocity fluctuations in different cerebral vessels (arteries, veins, sinuses), as well as in a laboratory model of carotid bifurcation. Derived equation describes the rheology of the ”blood stream - elastic vessel wall gelatinous brain environment” composite system and represents the state equation of this complex environment.

  18. Risk factors for small-vessel disease revealed by magnetic resonance imaging of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Kohriyama, Tatsuo; Yamaguchi, Shinya; Yamamura, Yasuhiro; Nakamura, Shigenobu [Hiroshima Univ. (Japan). School of Medicine; Tanaka, Eiji

    1996-02-01

    In total, 133 patients with asymptomatic or symptomatic cerebral infarction were randomly selected for the study (64 males, 69 females). Among them 91 patients had a history of symptomatic cerebral infarction, 46 patients of hypertension, and 28 patients of diabetes mellitus. The MRI scans were reviewed for areas with increased signal intensity on T2-weighted images. The grade of periventricular lesions, and the number of small infarctions in the subcortical white matter, basal ganglia and brain stem increased significantly with advancing age. It was thus reconfirmed that age is an important risk for demonstrating small-vessel disease on brain MRI. In addition, the degree of small-vessel disease on brain MRI was more extensive in patients with symptomatic cerebral infarction than with asymptomatic cerebral infarction. The detailed results suggest that small-vessel disease on brain MRI in patients with asymptomatic cerebral infarction might represent preclinical lesions for symptomatic cerebral infarction. The numbers of small infarctions in both the subcortical white matter and basal ganglia associated with advancing age, and histories of cerebrovascular accident and hypertension, suggest that common underlying mechanisms may exist in small-vessel disease in both the medullary arteries, which arise from cortical arteries, and perforating arteries. In the subcortical white matter, the number of patchy lesions was more strongly correlated with histories of hypertension and diabetes mellitus than was the number of spotty lesions, suggesting that the risk factors differed depending on the size of the lesions. The present study revealed that the degree of small-vessel disease on brain MRI was not correlated with the serum concentration of total cholesterol, triglyceride or HDL-cholesterol. The data thus indicate that the risk factors for small-vessel disease are distinct from those for large-vessel disease. (J.P.N.)

  19. Risk factors for small-vessel disease revealed by magnetic resonance imaging of the brain

    International Nuclear Information System (INIS)

    In total, 133 patients with asymptomatic or symptomatic cerebral infarction were randomly selected for the study (64 males, 69 females). Among them 91 patients had a history of symptomatic cerebral infarction, 46 patients of hypertension, and 28 patients of diabetes mellitus. The MRI scans were reviewed for areas with increased signal intensity on T2-weighted images. The grade of periventricular lesions, and the number of small infarctions in the subcortical white matter, basal ganglia and brain stem increased significantly with advancing age. It was thus reconfirmed that age is an important risk for demonstrating small-vessel disease on brain MRI. In addition, the degree of small-vessel disease on brain MRI was more extensive in patients with symptomatic cerebral infarction than with asymptomatic cerebral infarction. The detailed results suggest that small-vessel disease on brain MRI in patients with asymptomatic cerebral infarction might represent preclinical lesions for symptomatic cerebral infarction. The numbers of small infarctions in both the subcortical white matter and basal ganglia associated with advancing age, and histories of cerebrovascular accident and hypertension, suggest that common underlying mechanisms may exist in small-vessel disease in both the medullary arteries, which arise from cortical arteries, and perforating arteries. In the subcortical white matter, the number of patchy lesions was more strongly correlated with histories of hypertension and diabetes mellitus than was the number of spotty lesions, suggesting that the risk factors differed depending on the size of the lesions. The present study revealed that the degree of small-vessel disease on brain MRI was not correlated with the serum concentration of total cholesterol, triglyceride or HDL-cholesterol. The data thus indicate that the risk factors for small-vessel disease are distinct from those for large-vessel disease. (J.P.N.)

  20. Radiotherapy for Small Cerebral Arteriovenous Malformation

    OpenAIRE

    Yamashita, Tetsuo; Kurokawa, Yasushi; Kashiwagi, Shiro; Abiko, Seisho; Shiroyama, Yujiro; Kamiryo, Toshifumi; Nakano, Shigeki; Eguchi, Yuuki; Tsurutani, Toru; Ito, Haruhide

    1991-01-01

    The result of two types of radiation therapy for small cerebral arteriovenous malformations (AVM) were analyzed, and the indications and limitations of radiation therapy for small AVMs discussed. Four patients with small AVMs received radiation therapy. There were three males and one female, ranging in age from 7 to 44 years with an average of 29 years. One cerebral AVM was located in the right thalamus, two were in the left central sulcus and one was in the left parietal lobe. Three AVMs wer...

  1. 老年人慢性肾功能不全与脑小血管病变%Relationship between chronic kidney disease and cerebral small vessel disease in elderly patients

    Institute of Scientific and Technical Information of China (English)

    李华; 赵文新; 任苏虹; 孙芳; 段立晖; 严斌; 周国庆

    2009-01-01

    Objective To explore the relationship between chronic kidney disease (CKD) and cerebral small vessel disease (SVD) in elderly patients. Methods One hundred and fifty-two elderly male CKD patients for experimental group and 158 elderly male for control group were recruited. Demographic data and vascular risk factors were recorded. White matter lesion (WML) was semi-quantitatively assessed by cerebral magnetic resonance imaging (MRI), and lacunar infarction (LI) was also calculated. Results (1) The prevalenees of hypertentsion and diabetes mellitus were higher in elderly CKD patients than those in control group (30. 9% vs. 19.0%, 23.7%vs. 14.6%;both P~0. 05). (2) The percentages of grade 2 and grade 3 WMLs were higher in elderly CKD patients than those in control group (34.9% vs. 24.1%, 25.7% vs. 16.5%;both P<0.05). Prevalence of LI was higher in elderly CKD patients than that in control group (45.4% vs.25.3% ,X2= 13. 70, P<0. 05). The similar Results were also obtained except for control subjects with hypertension and diabetes mellitus. (3) The logistic regression analysis showed that age, hypertension and low glomerular filtration rate (GFR) were closely associated with SVD in elderly CKD patients. Conclusions Hypertention and diabetes mellitus are risk factors for CKD in elderly patients. SVD is associated with CKD, and age, hypertension and low GFR may be risk factors for SVD in elderly CKD patients.%目的 探讨老年人慢性肾功能不全(CKD)与脑小血管病变(SVD)的关系.方法 老年CKD组152例和老年对照受试者158例,均为男性,记录人口学资料和血管危险因素,根据头颅MRI结果 半定量评估脑白质病变(WML)和计算腔隙性梗死数(LI). 结果 (1)与对照组比较,老年CKD组高血压(30.9%对19.0%)、糖尿病(23.7%对14.6%)患病率明显升高(X2值分别为5.91和4.19,P<0.05);(2)与对照组比较,老年CKD组WML2级(34.9%对24.1%)和3级(25.7%对16.5%)比率明显升高(X2=4.37和3.96,P<0.05);LI

  2. Small vessel hematocrit in ischemic myocardium

    International Nuclear Information System (INIS)

    As blood enters the microvasculature of normally perfused myocardium, there is a progressive decrease in small vessel hematocrit (SV Hct) due to RBC streaming in smaller branching vessels and the Fahraeus-Lindqvist effect. We hypothesized that if the coronary collateral circulation was composed of very small vessels branching from large parent vessels, plasma streaming would result in a further decrease of SV Hct in ischemic myocardium. Six open chest anesthetized dogs were studied. Plasma was labelled with 59FeCl siderophilin and RBC's with 99mTc to estimate SV Hct from myocardial biopsies. The LAD was occluded and cannulated for measurement of retrograde flow (arising presumably from proximal collaterals). The ischemic region was identified using the microsphere shadow technique. Collateral flow after LAD occlusion was 30 +- 12 ml/min 100g (x +- SE). Systemic Hct was 40 +- 1%. The Hct of blood from retrograde flow was 39 +- 1% (p = NS). Activity of 59FeCl and 99mTc in known quantities of blood were compared to myocardial biopsies to estimate SV Hct. Ischemic SV Hct was 23 +- 2% and non-ischemic SV Hct was 21 +- 1% (p = NS). We conclude that the size and branching pattern of coronary collaterals is such that plasma streaming in collaterals does not result in an additional decrease in SV Hct in ischemic myocardium

  3. Mandrels For Microtextured Small-Vessel Implants

    Science.gov (United States)

    Deininger, William D.; Gabriel, Stephen B.

    1989-01-01

    Research shows artificial blood-vessel and heart-valve implants made more compatible with their biological environments by use of regularly microtextured surfaces. In new manufacturing process, ion beam etches patterned array of small pillars on mandrel used to mold tubular plastic implant. Pillars create tiny regularly spaced holes in inner surface of tube. Holes expected to provide sites for attachment of healthy lining. Polytetrafluoroethylene (PTFE) used as mandrel material because it can be etched by ion beam.

  4. Mechanism and treatment principle for cerebral vessel spasm caused by concussion

    Institute of Scientific and Technical Information of China (English)

    肖兴义; 郭新红; 王德文; 薛关生

    2002-01-01

    Objective: To discuss the mechanism of cerebral vessel spasm caused by concussion and the effect of Nimodipine on concussion. Methods: A total of 224 patients who were treated from March 1995 to October 1999 were divided into two groups randomly, ie, Nimodipine group (113 cases) and control group (111 cases). Middle cerebral artery (MCA), basilar artery (BA) and the average peak forward velocity of cerebral blood flow were observed by color three-dimensional transcranial Doppler (3D-TCD) within 24 hours after admission and at the end of 3-6 days of treatment. Cerebral blood flow changes, characteristics and treatment effect were analyzed and determined by clinical main symptom disappearance rate. Results: In concussion, cerebral blood flow was divided into 3 phases: cerebral blood flow low infusion dilation phase, cerebral blood vessel spasm phase and cerebral blood flow recovery phase. In the Nimodipine group, clinical main symptom disappearance rate was higher than that in the control group in the cerebral spasm and recovery phases with a significant difference (P<0.01).  Conclusions: Cerebral vessel spasm, hypoxia and ischemia lesion are the main pathological changes. Whether cerebral dysfunction is reversible or not is mainly determined by spasm time of cerebral blood vessel. Nimodipine has a good effect on releasing spasm and diminishing the cerebral blood flow velocity. It not only improves curative effect on concussion, but also reduces and prevents concussion sequelae. Hence, concussion patients who have cerebral spasm confirmed by 3D-TCD should be given Nimodipine routinely and early.

  5. Autonomous radiation monitoring of small vessels

    International Nuclear Information System (INIS)

    Small private vessels are one avenue by which nuclear materials may be smuggled across international borders. While one can contemplate using the land-based approach of radiation portal monitors on the navigable waterways that lead to many ports, these systems are ill-suited to the problem. In contrast to roadways, where lanes segregate vehicles, and motion is well controlled by inspection booths; channels, inlets, and rivers present chaotic traffic patterns populated by vessels of all sizes. A unique solution to this problem is based on a portal-less portal monitor designed to handle free-flowing traffic on roadways with up to five-traffic lanes. The instrument uses a combination of visible-light and gamma-ray imaging to acquire and link radiation images to individual vehicles. This paper presents the results of a recent test of the system in a maritime setting.

  6. The development of cerebral amyloid angiopathy in cerebral vessels. A review with illustrations based upon own investigated post mortem cases.

    Science.gov (United States)

    Mendel, T A; Wierzba-Bobrowicz, T; Lewandowska, E; Stępień, T; Szpak, G M

    2013-12-01

    The process of β-amyloid accumulation in cerebral vessels is presented. Cerebral amyloid angiopathy (CAA) was confirmed during an autopsy. It was diagnosed according to the Boston criteria. Cerebral amyloid angiopathy can involve all kinds of cerebral vessels (cortical and leptomeningeal arterioles, capillaries and veins). The development of CAA is a progressive process. β-amyloid appears first in the tunica media, surrounding smooth muscle cells, and in the adventitia. β-amyloid is progressively accumulated, causing a gradual loss of smooth muscle cells in the vessel wall and finally replacing them. Then, the detachment and delamination of the outer part of the tunica media results in the "double barrel" appearance, fibrinoid necrosis, and microaneurysm formation. Microbleeding with perivascular deposition of erythrocytes and blood breakdown products can also occur. β-amyloid can also be deposited in the surrounding of the affected vessels of the brain parenchyma, known as "dysphoric CAA". Ultrastructurally, when deposits of amyloid fibers were localized in or outside the arteriolar wall, the degenerating vascular smooth muscle cells were observed. In the Institute of Psychiatry and Neurology the study was carried out in a group of 48 patients who died due to intracerebral hemorrhage caused by sporadic CAA. PMID:24375040

  7. MDCTA diagnosis of cerebral vessel disease among patients with arterial hypertension

    International Nuclear Information System (INIS)

    to study changes involving cerebral vessels in patients with hypertension and various levels of total cardiovascular risk. One hundred and thirty-four patients underwent CT-angiography of intracranial vessels. Ninety-eight of them were diagnosed with hypertension. Taking into consideration high blood pressure, presence of risk factors and target organ damage subjects were divided into 4 groups: with low, medium, high and very high total cardiovascular risk. Control group included 36 patients. They were not diagnosed with hypertension at the time of examination. One hundred and five patients were examined using a 4-slice CT scanner (Toshiba Asteion 4, Toshiba Medical System, Japan), and 29 patients were examined using a 128-slice scanner (Siemens Definition AS+, Siemens Healthcare, Germany) with an injection system. We used iodine-containing contrast agents such as iodixanol and iopromide for angiography. Anatomical and topographic changes of cerebral vessels were most frequently found in hypertensive patients with high and very high total cardiovascular risk. Narrowing of vertebral vessels was the most common change (27 patients (27.55%), 21 patients (21.43%) had narrowing of the right artery, and 6 (6.12%) subjects – of the left one). Tortuous course of internal carotid arteries at the neck level was visualized in 11 patients (11.22%). Narrowing of A1 segment of anterior cerebral artery was noted in 9 patients (9.18%), of the right one – in 8 patients (8.16%), of the left one – in 1 patient (1.02%). Aneurysmal dilation of intracranial vessels was visualized in 6 patients (6.12%). Saccular aneurysm of left internal carotid artery was diagnosed in 2 patients (2.04%), one patient (1.02%) had right internal carotid artery aneurysm and one patient (1.02%) had an aneurysm of the basilar artery. the most common changes of cerebral vessels diagnosed in MDCTA among patients with hypertension included various degrees of narrowing of vertebral vessels, anterior

  8. PET Quantification of Cerebral Oxygen Metabolism in Small Animals

    OpenAIRE

    Takashi Temma; Kazuhiro Koshino; Tetsuaki Moriguchi; Jun-ichiro Enmi; Hidehiro Iida

    2014-01-01

    Understanding cerebral oxygen metabolism is of great importance in both clinical diagnosis and animal experiments because oxygen is a fundamental source of brain energy and supports brain functional activities. Since small animals such as rats are widely used to study various diseases including cerebral ischemia, cerebrovascular diseases, and neurodegenerative diseases, the development of a noninvasive in vivo measurement method of cerebral oxygen metabolic parameters such as oxygen extractio...

  9. Carotid artery wall stiffness is increased in patients with small vessel disease: A case-control study

    OpenAIRE

    Salihović-Hajdarević Denisa; Pavlović Aleksandra M.; Smajlović Dževdet; Podgorac Ana; Jovanović Zagorka; Švabić-Međedović Tamara; Čovičković-Šternić Nadežda

    2016-01-01

    Introduction. Cerebral ischemic small-vessel disease (SVD), causing lacunar infarcts and white matter hyperintensities on brain magnetic resonance imaging (MRI), is a progressive disease associated with an increased risk of stroke, dementia and death. Increased arterial stiffness has been associated with ischemic stroke and cerebral SVD independently of common vascular risk factors. Objective. The aim of the study was to analyze arterial stiffness in our pa...

  10. Functional photoacoustic micro-imaging of cerebral hemodynamic changes in single blood vessels after photo-induced brain stroke

    Science.gov (United States)

    Liao, Lun-De; Chen, You-Yin; Lin, Chin-Teng; Li, Meng-Lin

    2013-03-01

    Studying the functional hemodynamic roles of individual cerebral cortical arterioles in maintaining both the structure and function of cortical regions during and after brain stroke in small animals is an important issue. Recently, functional photoacoustic microscopy (fPAM) has been proved as a reliable imaging technique to probe the total hemoglobin concentration (HbT), cerebral blood volume (CBV) and hemoglobin oxygen saturation (SO2) in single cerebral blood vessels of rats. Here, we report the application of fPAM associated with electrophysiology recordings to investigating functional hemodynamic changes in single cortical arterioles of rats with electrical forepaw stimulation after photo-induced ischemic stroke. Because of the weak optical focusing nature of our fPAM system, photo-induced ischemic stroke targeting single cortical arterioles can be easily conducted with simple adaptation. Functional HbT, CBV and SO2 changes associated with the induced stroke in selected arterioles from the anterior cerebral artery system were imaged with 36 x 65-μm spatial resolution. Experimental results showed that after photo-occlusion of a single arteriole, the functional changes of nearby arterioles in cerebral cortex only can be observed immediately after the stroke. After a few minutes of stroke onset, there are no significant functional changes under the forepaw stimulation, suggesting that alternate blood flow routes are not actively recruited. The fPAM with electrophysiology recordings complements existing imaging techniques and has the potential to offer a favorable tool for explicitly studying cerebral hemodynamics in small animal models of photo-indcued ischemic stroke.

  11. Simultaneous imaging of intrinsic optical signals and cerebral vessel responses during cortical spreading depression in rats

    Science.gov (United States)

    Li, Pengcheng; Chen, Shangbin; Luo, Weihua; Luo, Qingming

    2003-12-01

    Cortical spreading depression (CSD) is an important disease model for migraine and cerebral ischemia. We investigated the spatio-temporal characteristics of the intrinsic optical signals (IOS) at 570 nm and the cerebral blood vessel responses during CSD simultaneously by optical reflectance imaging in vivo. The CSD were induced by pinprick in 10 α-chloralose/urethane anesthetized Sprague-Dawley rats. A four-phasic IOS response was observed at pial arteries and parenchymal sites in all experimental animals and an initial slight pial arteries dilation (21.5%+/-13.6%) and constriction (-4.2%+/-3.5%) precedes the dramatic dilation (69.2%+/-26.1%) of pial arterioles was recorded. Our experimental results show a high correlation (r = 0.89+/-0.025) between the IOS response and the diameter changes of the cerebral blood vessels during CSD in rats.

  12. Morphological changes of cerebral vessels and expression patterns of MMP-2 and MMP-9 on cerebrovascular wall of alcoholic rats.

    Science.gov (United States)

    Qi, Qian; Liu, Xia; Zhang, Guozhong; He, Wenjing; Ma, Rufei; Cong, Bin; Li, Yingmin

    2014-01-01

    Alcohol abuse increases the incidence of cerebral accidents, which correlates with cerebrovascular structural changes. The present study was designed to observe the cerebrovascular remodeling of drinking rats with light microscopy and transmission electron microscopy (TEM). Short-term alcohol administration induced apparent amplification of perivascular spaces around small vessels in brain tissue, while long-term administration caused pathological changes of basilar arteries (BAs), including endothelial exfoliation, inner elastic lamina (IEL) fragmentation and thickening of tunica media and adventitia. In addition, the relationship between cerebrovascular remodeling and MMP-2 and MMP-9 synthesized by endothelial cells and vascular smooth muscle cells was explored by immunohistochemistry. The two protein expression in cerebral vessels changed dynamically, peaking at 1-2 weeks after treatment, and decreasing as treatment continued. These results suggest that MMP-2 and MMP-9 may play a significant role in blood-brain barrier disruption after alcohol abuse. But the chronic changes of cerebral arteries resulted from drinking are not coincident with time course of MMP-2 and MMP-9 expression in situ. PMID:24966898

  13. The Significance of Small Cerebral Bleeds in Neurodegenerative Dementia Syndromes

    OpenAIRE

    De Reuck, Jacques L.

    2012-01-01

    Small cerebral bleeds are frequently observed in brains of patients with Alzheimer disease (AD) and cerebral amyloid angiopathy (CAA). However, they are also observed in patients with other neurodegenerative dementias and in persons without cognitive impairment. The aim of this survey is to compare the bleeding load in brains with different dementia syndromes and in age-matched controls. Hundred sixty-five brains were examined. The prevalence and the severity of the different cerebrovascular ...

  14. A CASE OF POLYCYTHEMIA SHOWING HYPERDENSE CEREBRAL VESSELS ON NON-CONTRAST COMPUTED TOMOGRAPHY SCAN

    Directory of Open Access Journals (Sweden)

    Bijit Kr

    2015-12-01

    Full Text Available Polycythemia is a disease state in which the proportion of blood volume that is occupied by red blood cells increases. It can result in increased density of intracranial blood vessels on non-contrast computed tomography scan. This imaging findings can closely mimic appearance of a contrast enhanced CT scan and those of cerebral venous thrombosis. We are presenting a case of 11-year-old child with Fallot’s tetralogy who showed abnormally hyperdense intracranial vessels on NCCT of brain.

  15. Coagulation and fibrinolytic parameters as predictors for small-vessel disease revealed by magnetic resonance imaging of the brain

    International Nuclear Information System (INIS)

    We correlated coagulation and fibrinolytic parameters with small-vessel disease revealed by magnetic resonance imaging (MRI) of the brain. One hundred and eleven patients with asymptomatic or symptomatic cerebral infarction were randomly selected for the study; 57 males and 54 females with an average age of 66.6±9.6, age range 40 to 85, years old. Among them, 76 patients had a history of symptomatic cerebral infarction; 38 patients hypertension; and 24 patients diabetes mellitus. Patients with large cortical infarction, cerebral hemorrhage, demyelinating disease or mass lesions were excluded from the present study. The MRI scans were reviewed for areas with increased signal intensity on T2-weighted images. The small infarction was defined as a lesion less than 10 mm in diameter. The activity of von Willebrand factor (vWF) correlated significantly with the grade of caps at the anterior and posterior horns of the lateral ventricle, and the number of small infarctions in the subcortical white matter and basal ganglia, suggesting vWF could be a predictor for these small-vessel disease. The grade of caps at posterior horn of the lateral ventricle and the number of small infarctions in the subcortical white matter were associated significantly with the concentration of plasma fibrinogen and reversely with the activity of antithrombin III, an inhibitory factor in coagulation system. These results indicate that hypercoagulable state may causatively relate with small-vessel disease in the territory of medullary artery branching from cortical artery. On the contrary, these coagulation parameters did not correlate significantly with small ischemic lesions in the territory of perforating artery. No correlation was observed between the level of marker proteins for platelet activation and the degree of small-vessel disease, indicating the activation of platelet could not associate with the etiology of small-vessel disease. (author)

  16. Longitudinal patterns of leukoaraiosis and brain atrophy in symptomatic small vessel disease.

    Science.gov (United States)

    Lambert, Christian; Benjamin, Philip; Zeestraten, Eva; Lawrence, Andrew J; Barrick, Thomas R; Markus, Hugh S

    2016-04-01

    Cerebral small vessel disease is a common condition associated with lacunar stroke, cognitive impairment and significant functional morbidity. White matter hyperintensities and brain atrophy, seen on magnetic resonance imaging, are correlated with increasing disease severity. However, how the two are related remains an open question. To better define the relationship between white matter hyperintensity growth and brain atrophy, we applied a semi-automated magnetic resonance imaging segmentation analysis pipeline to a 3-year longitudinal cohort of 99 subjects with symptomatic small vessel disease, who were followed-up for ≥1 years. Using a novel two-stage warping pipeline with tissue repair step, voxel-by-voxel rate of change maps were calculated for each tissue class (grey matter, white matter, white matter hyperintensities and lacunes) for each individual. These maps capture both the distribution of disease and spatial information showing local rates of growth and atrophy. These were analysed to answer three primary questions: first, is there a relationship between whole brain atrophy and magnetic resonance imaging markers of small vessel disease (white matter hyperintensities or lacune volume)? Second, is there regional variation within the cerebral white matter in the rate of white matter hyperintensity progression? Finally, are there regionally specific relationships between the rates of white matter hyperintensity progression and cortical grey matter atrophy? We demonstrate that the rates of white matter hyperintensity expansion and grey matter atrophy are strongly correlated (Pearson's R = -0.69,P< 1 × 10(-7)), and significant grey matter loss and whole brain atrophy occurs annually (P< 0.05). Additionally, the rate of white matter hyperintensity growth was heterogeneous, occurring more rapidly within long association fasciculi. Using voxel-based quantification (family-wise error correctedP< 0.05), we show the rate of white matter hyperintensity

  17. Small Vessel Contribution to Underwater Noise

    Energy Technology Data Exchange (ETDEWEB)

    Matzner, Shari; Maxwell, Adam R.; Myers, Joshua R.; Caviggia, Kurt A.; Elster, Jennifer L.; Foley, Michael G.; Jones, Mark E.; Ogden, George L.; Sorensen, Eric L.; Zurk, Lisa M.; Tagestad, Jerry D.; Stephan, Alex J.; Peterson, Mary E.; Bradley, Donald J.

    2010-12-10

    Understanding the types of noise generated by a small boat is important for ensuring that marine ecosystems are protected from detrimental anthropogenic noise. Here we present the results of a field test conducted to examine the effects of engine RPM, number of engines and number of propeller blades on the broadband and narrowband noise produced by a small boat. The test boat was a 23-foot aluminum-hulled boat with dual 100 hp engines. The broadband noise and narrowband peak levels were observed using two hydrophones in different locations. The broadband noise levels were affected by both the number of engines and the RPM; the narrowband peaks showed a greater increase in amplitude with an increase in RPM than the broadband noise levels.

  18. Perturbations of the cerebrovascular matrisome: A convergent mechanism in small vessel disease of the brain?

    Science.gov (United States)

    Joutel, Anne; Haddad, Iman; Ratelade, Julien; Nelson, Mark T

    2016-01-01

    The term matrisome refers to the ensemble of proteins constituting the extracellular matrix (ECM) (core matrisome) as well as the proteins associated with the ECM. Every organ has an ECM with a unique composition that not only provides the support and anchorage for cells, but also controls fundamental cellular processes as diverse as differentiation, survival, proliferation, and polarity. The current knowledge of the matrisome of small brain vessels is reviewed with a focus on the basement membrane (BM), a specialized form of ECM located at the interface between endothelial cells, contractile cells (smooth muscle cells and pericytes), and astrocyte endfeet—a very strategic location in the communication pathway between the cerebral microcirculation and astrocytes. We discuss some of the most recent genetic data and relevant findings from experimental models of nonamyloid cerebral small vessel disease (SVD). We propose the concept that perturbations of the cerebrovascular matrisome is a convergent pathologic pathway in monogenic forms of SVD, and is likely relevant to the sporadic disease. PMID:25853907

  19. Modeling the Role of the Glymphatic Pathway and Cerebral Blood Vessel Properties in Alzheimer's Disease Pathogenesis.

    Directory of Open Access Journals (Sweden)

    Christina Rose Kyrtsos

    Full Text Available Alzheimer's disease (AD is the most common cause of dementia in the elderly, affecting over 10% population over the age of 65 years. Clinically, AD is described by the symptom set of short term memory loss and cognitive decline, changes in mentation and behavior, and eventually long-term memory deficit as the disease progresses. On imaging studies, significant atrophy with subsequent increase in ventricular volume have been observed. Pathology on post-mortem brain specimens demonstrates the classic findings of increased beta amyloid (Aβ deposition and the presence of neurofibrillary tangles (NFTs within affected neurons. Neuroinflammation, dysregulation of blood-brain barrier transport and clearance, deposition of Aβ in cerebral blood vessels, vascular risk factors such as atherosclerosis and diabetes, and the presence of the apolipoprotein E4 allele have all been identified as playing possible roles in AD pathogenesis. Recent research has demonstrated the importance of the glymphatic system in the clearance of Aβ from the brain via the perivascular space surrounding cerebral blood vessels. Given the variety of hypotheses that have been proposed for AD pathogenesis, an interconnected, multilayer model offers a unique opportunity to combine these ideas into a single unifying model. Results of this model demonstrate the importance of vessel stiffness and heart rate in maintaining adequate clearance of Aβ from the brain.

  20. Ultrastructural analysis of small blood vessels in skin biopsies in CADASIL

    Directory of Open Access Journals (Sweden)

    Lačković Vesna

    2008-01-01

    Full Text Available Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL is an inherited small- and medium-artery disease of the brain caused by mutation of the Notch3 gene. Very often, this disease is misdiagnosed. We examined skin biopsies in two members of the first discovered Serbian family affected by CADASIL. Electron microscopy showed that skin blood vessels of both patients contain numerous deposits of granular osmiophilic material (GOM around vascular smooth muscle cells (VSMCs. We observed degeneration of VSMCs, reorganization of their cytoskeleton and dense bodies, disruption of myoendothelial contacts, and apoptosis. Our results suggest that the presence of GOM in small skin arteries represents a specific marker in diagnosis of CADASIL.

  1. Cerebral small-resistance artery structure and cerebral blood flow in normotensive subjects and hypertensive patients

    Energy Technology Data Exchange (ETDEWEB)

    De Ciuceis, Carolina; Porteri, Enzo; Rizzoni, Damiano; Boari, Gianluca E.M.; Rosei, Enrico Agabiti [University of Brescia, Clinica Medica, Department of Clinical and Experimental Sciences, Brescia (Italy); Cornali, Claudio; Mardighian, Dikran; Fontanella, Marco M. [University of Brescia, Section of Neurosurgery, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, Brescia (Italy); Pinardi, Chiara [Spedali Civili, Medical Physics Unit, Brescia (Italy); University of Brescia, Section of Neuroradiology, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, Brescia (Italy); Rodella, Luigi F.; Rezzani, Rita [University of Brescia, Section of Anatomy, Department of Clinical and Experimental Sciences, Brescia (Italy); Gasparotti, Roberto [University of Brescia, Section of Neurosurgery, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, Brescia (Italy); University of Brescia, Section of Neuroradiology, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, Brescia (Italy)

    2014-12-15

    The aim of this study was to prospectively investigate whether the structure of cerebral small-resistance arteries is related to cerebral perfusion parameters as measured with dynamic susceptibility-weighted contrast magnetic resonance imaging (DSC-MRI) in a selected cohort of hypertensive and normotensive patients. Ten hypertensive and 10 normotensive patients were included in the study. All patients underwent neurosurgical intervention for an intracranial tumor and were investigated with DSC-MRI at 1.5 T. Cerebral small-resistance arteries were dissected from a small portion of morphologically normal cerebral tissue and mounted on an isometric myograph for the measurement of the media-to-lumen (M/L) ratio. A quantitative assessment of cerebral blood flow (CBF) and volume (CBV) was performed with a region-of-interest approach. Correlation coefficients were calculated for normally distributed variables. The institutional review board approved the study, and informed consent was obtained from all patients. Compared with normotensive subjects, hypertensive patients had significantly lower regional CBF (mL/100 g/min) in the cortical grey matter (55.63 ± 1.90 vs 58.37 ± 2.19, p < 0.05), basal ganglia (53.34 ± 4.39 vs 58.22. ± 4.33, p < 0.05), thalami (50.65 ± 3.23 vs 57.56 ± 4.45, p < 0.01), subcortical white matter (19.32 ± 2.54 vs 22.24 ± 1.9, p < 0.05), greater M/L ratio (0.099 ± 0.013 vs 0.085 ± 0.012, p < 0.05), and lower microvessel density (1.66 ± 0.67 vs 2.52 ± 1.28, p < 0.05). A statistically significant negative correlation was observed between M/L ratio of cerebral arteries and CBF in the cortical grey matter (r = -0.516, p < 0.05), basal ganglia (r = -0.521, p < 0.05), thalami (r = -0.527 p < 0.05), and subcortical white matter (r = -0.612, p < 0.01). Our results indicate that microvascular structure might play a role in controlling CBF, with possible clinical consequences. (orig.)

  2. Comprehensive gene expression profiling reveals synergistic functional networks in cerebral vessels after hypertension or hypercholesterolemia.

    Directory of Open Access Journals (Sweden)

    Wei-Yi Ong

    Full Text Available Atherosclerotic stenosis of cerebral arteries or intracranial large artery disease (ICLAD is a major cause of stroke especially in Asians, Hispanics and Africans, but relatively little is known about gene expression changes in vessels at risk. This study compares comprehensive gene expression profiles in the middle cerebral artery (MCA of New Zealand White rabbits exposed to two stroke risk factors i.e. hypertension and/or hypercholesterolemia, by the 2-Kidney-1-Clip method, or dietary supplementation with cholesterol. Microarray and Ingenuity Pathway Analyses of the MCA of the hypertensive rabbits showed up-regulated genes in networks containing the node molecules: UBC (ubiquitin, P38 MAPK, ERK, NFkB, SERPINB2, MMP1 and APP (amyloid precursor protein; and down-regulated genes related to MAPK, ERK 1/2, Akt, 26 s proteasome, histone H3 and UBC. The MCA of hypercholesterolemic rabbits showed differentially expressed genes that are surprisingly, linked to almost the same node molecules as the hypertensive rabbits, despite a relatively low percentage of 'common genes' (21 and 7% between the two conditions. Up-regulated common genes were related to: UBC, SERPINB2, TNF, HNF4A (hepatocyte nuclear factor 4A and APP, and down-regulated genes, related to UBC. Increased HNF4A message and protein were verified in the aorta. Together, these findings reveal similar nodal molecules and gene pathways in cerebral vessels affected by hypertension or hypercholesterolemia, which could be a basis for synergistic action of risk factors in the pathogenesis of ICLAD.

  3. The Influence of Dome Size, Parent Vessel Angle, and Coil Packing Density on Coil Embolization Treatment in Cerebral Aneurysms

    Science.gov (United States)

    Frakes, David H.; Indahlastari, Aprinda; Ryan, Justin; Babiker, M. Haithem; Nair, Priya; Parthas, Varsha

    2013-11-01

    Intracranial aneurysms (ICAs) are dilated cerebral blood vessels. Treating ICAs effectively prior rupture is crucial since their association with 45% mortality rate. Embolic coiling is the most effective ICA treatment. Series of embolic coils are deployed into the aneurysm with the intent of reaching a sufficient packing density (PD) to help seal off the ICA from circulation. While coiling is effective, treatment failures have been associated with basilar tip aneurysms (BTAs), perhaps because of their geometry. The aim of this study was to examine the effect of dome size, parent vessel (PV) angle, and PD on intraaneurysmal (IA) velocity, crossneck (CN) flow and low wall shear stress (WSS) area using simulations and experiments in idealized BTA models. IA velocity and CN flow decreased after coiling, while low WSS area increased. With increasing PD, IA velocity and CN flow were further reduced, but low WSS area had a minimal change. Coil PD had the greatest impact on post-treatment flow while dome size had a greater impact than PV angle. Overall, the role of aneurysmal geometries may vary depending on treatment goal and timing e.g., high coil PD may reduce IA velocity more effectively during early aneurysmal growth when the dome size is small. Funded by the American Heart Association.

  4. Correlation of chronic kidney disease with diffusion tensor imaging in patients with cerebral small vessel disease%慢性肾脏病与脑小血管病患者磁共振弥散张量成像的相关性研究

    Institute of Scientific and Technical Information of China (English)

    朱阿娣; 张颖冬; 周俊山; 徐青青; 殷信道

    2015-01-01

    ObjectiveTo investigate the correlation of chronic kidney disease (CKD) with diffusion tensor imaging (DTI) in the patients with cerebral small vessel disease (SVD).Methods A total of 54 patients with confirmed SVD according to expert consensus admitted in the Nanjing Hospital from October 2012 to May 2014 were enrolled in this study. They were divided into 2 groups based on the glomerular filtration rate (GFR): CKD group [GFR<60(ml/min·1.73)m2,n=17] and non-CKD group (n=37). All of them received conventional magnetic resonance imaging (MRI) and DTI. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were measured in the regions of interest. The correlation of FA and ADC with GFR was analyzed.Results Compared to the non-CKD group, the CKD group had significantly lower FA values in the bilateral centrum semiovale, thalamus and right frontal lobes (P<0.05), and obviously higher ADC values of the bilateral centrum semiovale and the right frontal lobes (P<0.05). Pearson correlation analysis showed that the FA values of bilateral centrum semiovale and left thalamus were positively correlated with GFR (r=0.591,P=0.000;r=0.544,P=0.000;r=0.282,P=0.039), and the ADC values of bilateral centrum semiovale were negatively correlated with GFR (r=-0.490,P=0.000;r=-0.405,P=0.002).Conclusion DTI can more sensitively detect the cerebral microstructural changes in SVD patients, and is closely associated with GFR. So it can be used to evaluate CKD complicated with SVD.%目的:探讨慢性肾脏病(CKD)与脑小血管病(SVD)患者磁共振弥散张量成像(DTI)的关系。方法选取2012年10月至2014年5月南京医科大学附属南京医院神经内科诊治的54例SVD患者,根据肾小球滤过率(GFR)将患者分为CKD组(17例)和非CKD组(37例)。行常规磁共振成像(MRI)和DTI检查,观察感兴趣区部分各向异性(FA)及表观扩散系数(ADC)的变化,分析FA、ADC值

  5. 脑梗死患者脑血管血液动力学变化与功能障碍相关性研究%Correlation of hemodynamic change of cerebral vessels and functional disturbance in cerebral infarction patient

    Institute of Scientific and Technical Information of China (English)

    王伯良; 王俊卿

    2001-01-01

    Objective To observe and investigate the correlation of hemodynamic change of cerebral vessels and functional disturbance in cerebral infarction patient.Methods To investigate hemodynamic characters of cerebral vessels in every type and every group patients via comparing cerebral infarction group(observe group)with control group,comparing stage of recovery with early stage, sever, moderate, mild degree in observe group.Results Apparent hemodynamic change was observed in above 94.10% cerebral infarction patients. The more apparent the hemodynamic change,the severer the functional disturbance.Conclusion The hemodynamic change of cerebral vessels is the predictive index of state of illness and prognosis of cerebral infarction patient.Clinical doctor should pay enough attention to modify it in treatment.

  6. In vivo imaging of stepwise vessel occlusion in cerebral photothrombosis of mice by 19F MRI.

    Directory of Open Access Journals (Sweden)

    Gesa Weise

    Full Text Available BACKGROUND: (19F magnetic resonance imaging (MRI was recently introduced as a promising technique for in vivo cell tracking. In the present study we compared (19F MRI with iron-enhanced MRI in mice with photothrombosis (PT at 7 Tesla. PT represents a model of focal cerebral ischemia exhibiting acute vessel occlusion and delayed neuroinflammation. METHODS/PRINCIPAL FINDINGS: Perfluorocarbons (PFC or superparamagnetic iron oxide particles (SPIO were injected intravenously at different time points after photothrombotic infarction. While administration of PFC directly after PT induction led to a strong (19F signal throughout the entire lesion, two hours delayed application resulted in a rim-like (19F signal at the outer edge of the lesion. These findings closely resembled the distribution of signal loss on T2-weighted MRI seen after SPIO injection reflecting intravascular accumulation of iron particles trapped in vessel thrombi as confirmed histologically. By sequential administration of two chemically shifted PFC compounds 0 and 2 hours after illumination the different spatial distribution of the (19F markers (infarct core/rim could be visualized in the same animal. When PFC were applied at day 6 the fluorine marker was only detected after long acquisition times ex vivo. SPIO-enhanced MRI showed slight signal loss in vivo which was much more prominent ex vivo indicative for neuroinflammation at this late lesion stage. CONCLUSION: Our study shows that vessel occlusion can be followed in vivo by (19F and SPIO-enhanced high-field MRI while in vivo imaging of neuroinflammation remains challenging. The timing of contrast agent application was the major determinant of the underlying processes depicted by both imaging techniques. Importantly, sequential application of different PFC compounds allowed depiction of ongoing vessel occlusion from the core to the margin of the ischemic lesions in a single MRI measurement.

  7. Transportable, small high-pressure preservation vessel for cells

    Energy Technology Data Exchange (ETDEWEB)

    Kamimura, N; Sotome, S; Shimizu, A [Department of Environmental Engineering for Symbiosis, Soka University, 1-236 Tangi-cho, Hachioji, Tokyo 192-8577 (Japan); Nakajima, K [Department of Bioinformatics, Soka University, 1-326 Tangi-cho, Hachioji, Tokyo 192-8577 (Japan); Yoshimura, Y, E-mail: mf_kamimura@yahoo.co.j [Department of Applied Chemistry, National Defence Academy, 1-10-20 Hashirimizu, Yokosuka, Kanagawa 239-8686 (Japan)

    2010-03-01

    We have previously reported that the survival rate of astrocytes increases under high-pressure conditions at 4{sup 0}C. However, pressure vessels generally have numerous problems for use in cell preservation and transportation: (1) they cannot be readily separated from the pressurizing pump in the pressurized state; (2) they are typically heavy and expensive due the use of materials such as stainless steel; and (3) it is difficult to regulate pressurization rate with hand pumps. Therefore, we developed a transportable high-pressure system suitable for cell preservation under high-pressure conditions. This high-pressure vessel has the following characteristics: (1) it can be easily separated from the pressurizing pump due to the use of a cock-type stop valve; (2) it is small and compact, is made of PEEK and weighs less than 200 g; and (3) pressurization rate is regulated by an electric pump instead of a hand pump. Using this transportable high-pressure vessel for cell preservation, we found that astrocytes can survive for 4 days at 1.6 MPa and 4{sup 0}C.

  8. Computer-assisted spatial reconstruction of cerebral blood vessels and intracranial aneurysms

    Directory of Open Access Journals (Sweden)

    Nikolić Igor M.

    2006-01-01

    Full Text Available Introduction. Today, many medical procedures are based on image analysis with the aim of providing accurate diagnosis and optimal treatment. The goal of this report was to present clinical implications of computer-assisted geometric design of carotid aneurysms. Material and methods. In this study, the three-dimensional reconstruction was based on the approximation power of the parametric spline function, which achieves interpolation and surface fitting of the arterial information obtained by conventional angiography. Two views of conventional angiograms (anterioposterior and lateral views were used with a personal computer and commercial software. Results. This method of three-dimensional generated images was applied in 45 cases of cerebral aneurysms in carotid bifurcation. 3D reconstructions were made in approximately 20 minutes. They contributed to assessing vascular structures, and it was possible to rotate the three-dimensional image in different angles. Conclusion. Three-dimensional reconstruction of cerebral vessels is very useful for discussing surgical strategies preoperatively. Furthermore, it could also be used in endovascular procedures. .

  9. Quantitative CT analysis of small pulmonary vessels in lymphangioleiomyomatosis

    International Nuclear Information System (INIS)

    Backgrounds: Lymphangioleiomyomatosis (LAM) is a destructive lung disease that share clinical, physiologic, and radiologic features with chronic obstructive pulmonary disease (COPD). This study aims to identify those features that are unique to LAM by using quantitative CT analysis. Methods: We measured total cross-sectional areas of small pulmonary vessels (CSA) less than 5 mm2 and 5–10 mm2 and calculated percentages of those lung areas (%CSA), respectively, in 50 LAM and 42 COPD patients. The extent of cystic destruction (LAA%) and mean parenchymal CT value were also calculated and correlated with pulmonary function. Results: The diffusing capacity for carbon monoxide/alveolar volume (DLCO/VA %predicted) was similar for both groups (LAM, 44.4 ± 19.8% vs. COPD, 45.7 ± 16.0%, p = 0.763), but less tissue damage occurred in LAM than COPD (LAA% 21.7 ± 16.3% vs. 29.3 ± 17.0; p CO/VA %predicted, %CSA and mean parenchymal CT value were still greater for LAM than COPD (p < 0.05). Conclusions: Quantitative CT analysis revealing a correlation between cystic destruction and CSA in COPD but not LAM indicates that this approach successfully reflects different mechanisms governing the two pathologic courses. Such determinations of small pulmonary vessel density may serve to differentiate LAM from COPD even in patients with severe lung destruction.

  10. 'Variant' angina: Evidence for small vessel coronary artery spasm

    International Nuclear Information System (INIS)

    A unique case of 'variant' angina pectoris has been observed in a patient with normal coronary arteries and typical chest pain appearing spontaneously at rest, and repeatedly provoked by ergonovine maleate (0.1 mg iv) associated with large transmural perfusion defects on 201TI-imaging (after ergonovine) and a marked increase in T wave voltage despite no demonstrable spasm of a major coronary artery after the same doses of ergonovine. While saline solution could not provoke chest pain and treatment with a beta-blocking agent increased the frequency of ischemic attacks, a calcium antangonist therapy reduced and eventually eliminated the attacks. Thus, this case provides evidence for yet another aspect of a 'variant' form of angina pectoris: small vessel coronary artery spasm. (orig.)

  11. Quantitative CT analysis of small pulmonary vessels in lymphangioleiomyomatosis

    Energy Technology Data Exchange (ETDEWEB)

    Ando, Katsutoshi, E-mail: kando@juntendo.ac.jp [Department of Internal Medicine, Division of Respiratory Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421 (Japan); The Study Group of Pneumothorax and Cystic Lung Diseases, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan); Tobino, Kazunori [Department of Respiratory Medicine, Iizuka Hospital, 3-83 Yoshio-Machi, Iizuka-City, Fukuoka 820-8505 (Japan); The Study Group of Pneumothorax and Cystic Lung Diseases, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan); Kurihara, Masatoshi; Kataoka, Hideyuki [Pneumothorax Center, Nissan Tamagawa Hospital, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan); The Study Group of Pneumothorax and Cystic Lung Diseases, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan); Doi, Tokuhide [Fukuoka Clinic, 7-18-11 Umeda, Adachi-Ku, Tokyo 123-0851 (Japan); Hoshika, Yoshito [Department of Internal Medicine, Division of Respiratory Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421 (Japan); The Study Group of Pneumothorax and Cystic Lung Diseases, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan); Takahashi, Kazuhisa [Department of Internal Medicine, Division of Respiratory Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421 (Japan); Seyama, Kuniaki [Department of Internal Medicine, Division of Respiratory Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421 (Japan); The Study Group of Pneumothorax and Cystic Lung Diseases, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan)

    2012-12-15

    Backgrounds: Lymphangioleiomyomatosis (LAM) is a destructive lung disease that share clinical, physiologic, and radiologic features with chronic obstructive pulmonary disease (COPD). This study aims to identify those features that are unique to LAM by using quantitative CT analysis. Methods: We measured total cross-sectional areas of small pulmonary vessels (CSA) less than 5 mm{sup 2} and 5–10 mm{sup 2} and calculated percentages of those lung areas (%CSA), respectively, in 50 LAM and 42 COPD patients. The extent of cystic destruction (LAA%) and mean parenchymal CT value were also calculated and correlated with pulmonary function. Results: The diffusing capacity for carbon monoxide/alveolar volume (DL{sub CO}/VA %predicted) was similar for both groups (LAM, 44.4 ± 19.8% vs. COPD, 45.7 ± 16.0%, p = 0.763), but less tissue damage occurred in LAM than COPD (LAA% 21.7 ± 16.3% vs. 29.3 ± 17.0; p < 0.05). Pulmonary function correlated negatively with LAA% (p < 0.001) in both groups, yet the correlation with %CSA was significant only in COPD (p < 0.001). When the same analysis was conducted in two groups with equal levels of LAA% and DL{sub CO}/VA %predicted, %CSA and mean parenchymal CT value were still greater for LAM than COPD (p < 0.05). Conclusions: Quantitative CT analysis revealing a correlation between cystic destruction and CSA in COPD but not LAM indicates that this approach successfully reflects different mechanisms governing the two pathologic courses. Such determinations of small pulmonary vessel density may serve to differentiate LAM from COPD even in patients with severe lung destruction.

  12. Stroke severity and incidence of acute large vessel occlusions in patients with hyper-acute cerebral ischemia

    DEFF Research Database (Denmark)

    Hansen, Christine Kraup; Christensen, Anders Fogh; Ovesen, C;

    2015-01-01

    vessel occlusions and describe the relations to the National Institutes of Health Stroke Scale (NIHSS), lesion site and time from symptom onset in unselected consecutive patients with hyper-acute cerebral ischemia. METHODS: A prospective single hospital registry was based on consecutive unselected...... occlusions and the effect of time after symptom onset was assessed. RESULTS: Six hundred thirty-seven patients, with admission NIHSS: 1-42, were included; 183 patients presented with acute vessel occlusions (28.7%) in 15 different combinations of occlusions. The best NIHSS-cut-off for detecting any occlusion...

  13. Characteristics of global cerebral ischemia models constructed by modified four-vessel occlusion in rats

    Institute of Scientific and Technical Information of China (English)

    Jinbao Li; Lai Jiang; Hua Xu; Yuanchang Xiong; Xiaoming Deng

    2006-01-01

    BACKGROUND: Pulsinelli et al developed a kind of rat models with four-vessel occlusion-induced global cerebral ischemia. Because the histo-pathological changes and severe cerebral ischemia reproducibility of this model are good and the stability of this model in circulation respiration is superior to that of other models, so four-vessel occlusion method has become a classic modeling method for global cerebral ischemia model. This model has been improved in some laboratories to meet different requirements in different studies. OBJECTIVE: To establish a highly reproducible rat model of reversible forebrain ischemia by modifying four-vessel occlusion model introduced by Pulsinelli et al, and to investigate its neurophysiological and pathological changes and the characteristics of modified operation. DESIGN: Completely randomized grouping, controlled trial. SETTING: Department of Anesthesiology,Changhai Hospital, Second Military Medical University of Chinese PLA. MATERIALS: A total of 65 male healthy SD rats, weighing 250-300 g, were provided by the Experimental Animal Center of Second Military Medical University of Chinese PLA. VSM hemodynamic monitor and temperature monitor (Thermal ert TH-5, U.S.A) were used.METHODS: The trial was conducted in the Department of Anesthesiology, Changhai Hospital, Second Military Medical University of Chinese PLA from January 2005 to March 2006. ① Experimental grouping: Sixty-five rats were randomly divided into the following 7 groups: sham-operation group (n =9): given the same operation, without occlusion of vessels; 5 minutes ischemia group (n =9): ischemia 5 minutes and reperfusion 72 hours; 10 minutes ischemia group (n =8): ischemia 10 minutes and reperfusion 72 hours; 15 minutes ischemia group (n =9): ischemia 15 minutes and reperfusion 72 hours; 20 minutes ischemia group (n =8): ischemia 20 minutes and reperfusion 72 hours; 30 minutes ischemia group (n =7); ischemia 30 minutes and reperfusion 72 hours; ischemia control group

  14. The changes of oxygen extraction fraction and cerebral blood flow of brain parenchyma in patients with unilateral cerebral vessel stenosis: initial experience of the quantitative measurements

    International Nuclear Information System (INIS)

    Objective: Using gradient-echo sampling of spin-echo (GESSE) sequence to study the change of oxygen extraction fraction (OEF) in patients with unilateral cerebral vessel stenosis and the relationship between OEF and cerebral blood flow (CBF). Methods: Eight normal volunteers and 16 patients with unilateral cerebral vessel stenosis were enrolled in this study. Written informed consents were obtained from all subjects. Routine MRI, GESSE and arterial spin labeling (ASL) sequences were performed for all patients. Raw data from GESSE and VE-ASL sequences were transferred to PC to conduct postprocessing. To obtain quantitative OEF and CBF of the brain parenchyma, 6 ROIs were placed respectively in the anterior, middle and posterior part of both hemispheres. The relative CBF (rCBF) was defined as the ratio of CBF of ischemic hemisphere to that of contralateral hemisphere. T test was used for statistics. Results: The mean value and normal range of OEF in the volunteers were 0.318±0.023 and 0.272-0.364, respectively. In the 16 patients with unilateral cerebral vessel stenosis, 8 patients had ROIs with greater OEF iri unilateral hemisphere than those in contralateral hemisphere. These cases presented multiple intracranial main arterial stenoses in digital subtraction angiography (DSA) or MR angiography (MRA) examination. The other 8 patients had normal OEF in all ROIs. And they only had single arterial stenosis in DSA or MRA. Set rCBF = 0.50 as a dividing point, the mean OEF value was 0.397±0.010 in the patients with rCBF < 0.50. In the patients with rCBF ≥ 0.5, the mean OEF value was 0.325± 0.028. The difference between the two groups was statistically significant (t=-8.840, P=0.000). Conclusion: Patients with chronic cerebral ischemia may present with various hemodynamic impairment. The more CBF decreases, the more OEF increases. Those with increased OEF tended to have more than one lesion in the major intracranial arteries. (authors)

  15. 蒙特利尔认知量表在脑小血管病患者认知功能障碍筛查中的作用%Value of the Montreal cognitive assessment for the detection of vascular cognitive impairment in cerebral small vessel disease

    Institute of Scientific and Technical Information of China (English)

    孔凡斌; 杨芳; 陈卫; 赵仁亮

    2011-01-01

    目的 探讨蒙特利尔认知量表(MoCA)在脑小血管病(SVD)患者认知功能障碍评估中的意义.方法 将103 例SVD 患者分为认知功能正常组和认知功能障碍组,应用MoCA 量表及简易精神状态量表(MMSE)对所有患者进行认知功能评估.结果 (1)两组患者在年龄、性别、教育程度方面无统计学差异(P >0.05).(2)认知功能障碍组MoCA 总分为18.20 ±3.42,MMSE 总分为25.53 ±2.91,两结果之间具有相关性,Spearman 相关系数r =0.531(P <0.05).(3)两组之间相比较,除注意子项外,MoCA 量表其余子项目及总分均有统计学差异,而MMSE 量表只有总分、记忆子项及回忆子项有统计学差异.(4)应用最大约登指数确定MoCA 量表识别SVD 所致认知障碍的最佳截断值为22/23 分,此时MoCA 量表的敏感度和特异度分别为91.9%和95.1%.结论 MoCA 量表在SVD 患者认知功能障的筛查中具有较高的敏感性和特异性,其最佳截断值为22/23 分.%Objective Cognitive impairment that is caused by or associated with vascular factors has been termed " vascular cognitive impairment " , which comprises vascular dementia ( VD ) and vascular cognitive impairment no-dementia ( VCIND). VCIND is a term that broadly encompasses cognitive deficits associated with vascular disease which fall short of a dementia diagnosis . In this study we aimed to evaluate the validity of Montreal cognitive assessment in cognitive impairment caused by cerebral small vessel disease ( SVD). Methods According to the diagnostic criteria, 103 patients with SVD were divided into two groups , cognitive impairment group ( n = 62 ) and the control ( n = 41). All the patients were assessed with MoCA and MMSE. Results ( 1 ) No significant differences were found between the two groups on age , gender and education level (P >0. 05). (2)The total scores of MoCA and MMSE were 18. 20 ±3. 42,25. 53 ±2.91, respectively in the cognitive impairment group. There was high correlation

  16. Diet Induced Obesity Causes Cerebral Vessel Remodeling and Increases the Damage Caused by Ischemic Stroke

    OpenAIRE

    Deutsch, Christian; Portik-Dobos, Vera; Smith, Anita D; Ergul, Adviye; Dorrance, Anne M.

    2009-01-01

    Hypertension, elevated fasting blood glucose and plasma insulin develop in rats fed a high fat (HF) diet. Our goal was to assess the effects of obesity, beginning in childhood, on the adult cardiovascular system. We hypothesized that rats fed a HF diet would have larger ischemic cerebral infarcts and middle cerebral artery (MCA) remodeling. Three-week-old male Sprague Dawley rats were fed a HF (Obese) or control diet for 10 weeks. Cerebral ischemia was induced by MCA occlusion (MCAO). MCA str...

  17. Pulmonary Hypertension and Computed Tomography Measurement of Small Pulmonary Vessels in Severe Emphysema

    OpenAIRE

    Matsuoka, Shin; George R. Washko; Yamashiro, Tsuneo; Estepar, Raul San Jose; Diaz, Alejandro; Silverman, Edwin K.; Hoffman, Eric; Fessler, Henry E.; Criner, Gerard J.; Marchetti, Nathaniel; Scharf, Steven M; Martinez, Fernando J; Reilly, John J.; Hatabu, Hiroto

    2009-01-01

    Rationale: Vascular alteration of small pulmonary vessels is one of the characteristic features of pulmonary hypertension in chronic obstructive pulmonary disease. The in vivo relationship between pulmonary hypertension and morphological alteration of the small pulmonary vessels has not been assessed in patients with severe emphysema.

  18. Thiazine Red(+) platelet inclusions in Cerebral Blood Vessels are first signs in an Alzheimer's Disease mouse model.

    Science.gov (United States)

    Kniewallner, Kathrin M; Wenzel, Daniela; Humpel, Christian

    2016-01-01

    Strong evidence shows an association between cerebral vascular diseases and Alzheimer´s disease (AD). In order to study the interaction of beta-amyloid (Aβ) plaques with brain vessels, we crossbred an AD mouse model (overexpressing amyloid precursor protein with the Swedish-Dutch-Iowa mutations, APP_SweDI) with mice expressing green fluorescent protein (GFP) under the flt-1/VEGFR1 promoter in vessels (GFP_FLT1). Our data show, that only very few Aβ plaques were seen in 4-months old mice, focused in the mammillary body and in the lateral septal nucleus. The number of plaques markedly increased with age being most prominent in 12-months old mice. Thiazine Red was used to verify the plaques. Several Thiazine Red(+) inclusions were found in GFP(+) vessels, but only in non-perfused 4-months old mice. These inclusions were verified by Resorufin stainings possibly representing cerebral amyloid angiopathy. The inclusions were also seen in non-crossbred APP_SweDI but not in wildtype and GFP_FLT1 mice. In order to characterize these inclusions Flow Cytometry (FACS) analysis demonstrated that platelets were specifically stained by Thiazine Red(+), more pronounced when aggregated. In conclusion, our data show that Thiazine Red(+) inclusions representing aggregated platelets are a first pathological sign in AD before plaque development and may become important therapeutic targets in early AD. PMID:27345467

  19. Mathematical modeling of patient-specific ventricular assist device implantation to reduce particulate embolization rate to cerebral vessels.

    Science.gov (United States)

    Ricardo Argueta-Morales, I; Tran, Reginald; Ceballos, Andres; Clark, William; Osorio, Ruben; Divo, Eduardo A; Kassab, Alain J; DeCampli, William M

    2014-07-01

    Stroke is the most devastating complication after ventricular assist device (VAD) implantation, with an incidence of 14%-47% despite improvements in device design and anticoagulation. This complication continues to limit the widespread implementation of VAD therapy. Patient-specific computational fluid dynamics (CFD) analysis may elucidate ways to reduce this risk. A patient-specific three-dimensional model of the aortic arch was generated from computed tomography. A 12 mm VAD outflow-graft (VAD-OG) "anastomosed" to the aorta was rendered. CFD was applied to study blood flow patterns. Particle tracks, originating from the VAD, were computed with a Lagrangian phase model and percentage of particles entering the cerebral vessels was calculated. Twelve implantation configurations of the VAD-OG and three particle sizes (2, 4, and 5 mm) were considered. Percentage of particles entering the cerebral vessels ranged from 6% for the descending aorta VAD-OG anastomosis, to 14% for the ascending aorta at 90 deg VAD-OG anastomosis. Values were significantly different among all configurations (X(2) = 3925, p < 0.0001). Shallower and more cephalad anastomoses prevented formation of zones of recirculation in the ascending aorta. In this computational model and within the range of anatomic parameters considered, the percentage of particles entering the cerebral vessels from a VAD-OG is reduced by nearly 60% by optimizing outflow-graft configuration. Ascending aorta recirculation zones, which may be thrombogenic, can also be eliminated. CFD methods coupled with patient-specific anatomy may aid in identifying the optimal location and angle for VAD-OG anastomosis to minimize stroke risk. PMID:24441718

  20. Spatial distribution and evolution of cerebral microbleeds: impact on the clinical therapy

    International Nuclear Information System (INIS)

    Cerebral microbleeds reflect the pathological changes of cerebral small vessel diseases. It has characterized spatial distribution and evolution. The occurrence of microbleeds impacts on clinical treatment. Susceptibility weighted imaging can improve the detection of cerebral microbleeds which could help for the diagnosis and differential diagnosis. We reviewed the pathology, characteristics of spatial and evolution of cerebral microbleeds and its impact on clinical therapy. (authors)

  1. Triamcinolone Acetonide Selectively Inhibits Angiogenesis in Small Blood Vessels and Decreases Vessel Diameter within the Vascular Tree

    Science.gov (United States)

    McKay, Terri L.; Gredeon, Dan J.; Vickerman, Mary B.; Hylton, alan G.; Ribita, Daniela; Olar, Harry H.; Kaiser, Peter K.; Parsons-Wingerter, Patricia

    2007-01-01

    The steroid triamcinolone acetonide (TA) is a potent anti-angiogenesis drug used to treat retinal vascular diseases that include diabetic retinopathy, vascular occlusions and choroidal neovascularization. To quantify the effects of TA on branching morphology within the angiogenic microvascular tree of the chorioallantoic membrane (CAM) of quail embryos. Increasing concentrations of TA (0-16 ng/ml) were applied topically on embryonic day 7 (E7) to the chorioallantoic membrane (CAM) of quail embryos cultured in Petri dishes, and incubated for an additional 24 or 48 hours until fixation. Binary (black/white) microscopic images of arterial end points were quantified by VESGEN software (for Generational Analysis of Vessel Branching) to obtain major vascular parameters that include vessel diameter (Dv), fractal dimension (Df), tortuosity (Tv) and densities of vessel area, length, number and branch point (Av, Lv, Nv and Brv). For assessment of specific changes in vascular morphology induced by TA, the VESGEN software automatically segmented the vascular tree into branching generations (G1...G10) according to changes in vessel diameter and branching. Vessel density decreased significantly up to 34% as the function of increasing concentration of TA according to Av, Lv, Brv, Nv and Df. TA selectively inhibited the growth of new, small vessels, because Lv decreased from 13.14plus or minus 0.61 cm/cm2 for controls to 8.012 plus or minus 0.82 cm/cm2 at 16 ng TA/ml in smaller branching generations (G7-G10), and for Nv from 473.83 plus or minus 29.85 cm(-)2 to 302.32 plus or minus 33.09 cm-()2. In contrast, vessel diameter (Dv) decreased throughout the vascular tree (G1-G10).

  2. Age-dependent expression of VEGFR2 in deep brain arteries in small vessel disease, CADASIL, and healthy brains.

    Science.gov (United States)

    Ahmed-Jushuf, Fiyyaz; Jiwa, Nadim S; Arwani, Anum S; Foot, Peter; Bridges, Leslie R; Kalaria, Raj N; Esiri, Margaret M; Hainsworth, Atticus H

    2016-06-01

    Vascular myocytes are central to brain aging. Small vessel disease (SVD; arteriolosclerosis) is a widespread cause of lacunar stroke and vascular dementia and is characterized by fibrosis and depletion of vascular myocytes in small penetrating arteries. Vascular endothelial growth factor (VEGF) is associated with brain aging, and Immunolabeling for vascular endothelial growth factor receptor 2 (VEGFR2) is a potent determinant of cell fate. Here, we tested whether VEGFR2 in vascular myocytes is associated with older age and SVD in human brain. Immunolabeling for VEGFR2 in deep gray matter was assessed in older people with or without moderate-severe SVD or in younger people without brain pathology or with a monogenic form of SVD (Cerebral Autosomal-Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy). All cases were without Alzheimer's disease pathology. Myocyte VEGFR2 was associated with increasing age (p = 0.0026) but not with SVD pathology or with sclerotic index or blood vessel density. We conclude that VEGFR2 is consistently expressed in small artery myocytes of older people and may mediate effects of VEGF on brain vascular aging. PMID:27143427

  3. Real-time intraoperative full-range complex FD-OCT guided cerebral blood vessel identification and brain tumor resection in neurosurgery

    Science.gov (United States)

    Zhang, Kang; Huang, Yong; Pradilla, Gustavo; Tyler, Betty; Kang, Jin U.

    2011-03-01

    This work utilized an ultra-high-speed full-range complex-conjugate-free optical coherence tomography (FD-OCT) system to perform real-time intraoperative imaging to guide two common neurosurgical procedures: the cerebral blood vessel identification and the brain tumor resection. The cerebral blood vessel identification experiment is conducted ex vivo on human cadaver specimen. Specific cerebral arteries and veins in different positions of the specimen are visualized and the spatial relations between adjacent vessels are indentified through real-time 3D visualization. The brain tumor resection experiment is conducted in vivo on 9L gliomas established in rat brains. The normal brain-tumor margin can be clearly identified in depth of the tissue from sagittal, coronal and axial slices of the intraoperatively acquired 3D data set. The real-time full-range FD-OCT guided in vivo rat flank tumor resection is also conducted.

  4. Small Vessel Ischemic Disease of the Brain and Brain Metastases in Lung Cancer Patients

    OpenAIRE

    Mazzone, Peter J.; Marchi, Nicola; Fazio, Vince; Taylor, J. Michael; Masaryk, Thomas; Bury, Luke; Mekhail, Tarek; Janigro, Damir

    2009-01-01

    Background Brain metastases occur commonly in patients with lung cancer. Small vessel ischemic disease is frequently found when imaging the brain to detect metastases. We aimed to determine if the presence of small vessel ischemic disease (SVID) of the brain is protective against the development of brain metastases in lung cancer patients. Methodology/Principal Findings A retrospective cohort of 523 patients with biopsy confirmed lung cancer who had received magnetic resonance imaging of the ...

  5. Computed tomography depiction of small pediatric vessels with model-based iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Koc, Gonca; Courtier, Jesse L.; Phelps, Andrew; Marcovici, Peter A.; MacKenzie, John D. [UCSF Benioff Children' s Hospital, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States)

    2014-07-15

    Computed tomography (CT) is extremely important in characterizing blood vessel anatomy and vascular lesions in children. Recent advances in CT reconstruction technology hold promise for improved image quality and also reductions in radiation dose. This report evaluates potential improvements in image quality for the depiction of small pediatric vessels with model-based iterative reconstruction (Veo trademark), a technique developed to improve image quality and reduce noise. To evaluate Veo trademark as an improved method when compared to adaptive statistical iterative reconstruction (ASIR trademark) for the depiction of small vessels on pediatric CT. Seventeen patients (mean age: 3.4 years, range: 2 days to 10.0 years; 6 girls, 11 boys) underwent contrast-enhanced CT examinations of the chest and abdomen in this HIPAA compliant and institutional review board approved study. Raw data were reconstructed into separate image datasets using Veo trademark and ASIR trademark algorithms (GE Medical Systems, Milwaukee, WI). Four blinded radiologists subjectively evaluated image quality. The pulmonary, hepatic, splenic and renal arteries were evaluated for the length and number of branches depicted. Datasets were compared with parametric and non-parametric statistical tests. Readers stated a preference for Veo trademark over ASIR trademark images when subjectively evaluating image quality criteria for vessel definition, image noise and resolution of small anatomical structures. The mean image noise in the aorta and fat was significantly less for Veo trademark vs. ASIR trademark reconstructed images. Quantitative measurements of mean vessel lengths and number of branches vessels delineated were significantly different for Veo trademark and ASIR trademark images. Veo trademark consistently showed more of the vessel anatomy: longer vessel length and more branching vessels. When compared to the more established adaptive statistical iterative reconstruction algorithm, model

  6. Small vessel vasculitis History, classification, etiology, histopathology, clinic, diagnosis and treatment

    International Nuclear Information System (INIS)

    Small-vessel vasculitis is a convenient descriptor for a wide range of diseases characterized by vascular inflammation of the venules, capillaries, and/or arterioles with pleomorphic clinical manifestations. The classical clinical phenotype is leucocytoclastic vasculitis with palpable purpura, but manifestations vary widely depending upon the organs involved. Histopathologic examination in leucocytoclastic vasculitis reveals angiocentric segmental inflammation, fibrinoid necrosis, and a neutrophilic infiltrate around the blood vessel walls with erythrocyte extravasation. The etiology of small-vessel vasculitis is unknown in many cases, but in others, drugs, post viral syndromes, malignancy, primary vasculitis such as microscopic polyarteritis, and connective tissue disorders are associated, The diagnosis of small- vessel vasculitis relies on a thorough history and physical examination, as well as relevant antibody testing including antinuclear antibody and anti neutrophil cytoplasmic antibody, hepatitis B and C serologies, assessment of complement, immunoglobulins, blood count, serum creatinine liver function tests, urinalysis, radiographic imaging and biopsy. The treatment is based primarily on corticosteroid and immunosuppressive agents

  7. Noninvasive elasticity imaging in small vessels: validation on tissue-mimicking phantoms

    Science.gov (United States)

    Maurice, Roch L.; Daronat, Michel; Pivert, Nicolas; Foster, F. S.; Cloutier, Guy

    2004-04-01

    Non-invasive ultrasound elastography (NIVE) was recently introduced to characterize mechanical properties of superficial arteries. In this paper, the feasibility of NIVE for the purpose of studying small vessels in humans and small animals is investigated. The experiments were performed in vitro on vessel-mimicking phantoms of 1.5-mm lumen diameter and 1.5-mm wall thickness. Polyvinyl alcohol cryogel (PVA-C) was used to create double layer vessel walls. The stiffness of the interior portion of the vessels was made softer. The vessels were insonified at 32 MHz with an ultrasound biomicroscope. Radial stress was applied within the lumen of the phantom by applying incremental static pressure steps with a column of a flowing mixture of water-glycerol. The Lagrangian speckle tissue model estimator was used to assess the 2D-strain tensor, and the composite Von Mises elastograms were then computed. The two-layer vessel walls were clearly identifiable. Strain values close to 3% were measured for the interior portion, whereas strains around 1% were noted for the stiffer outside layer. In conclusion, the feasibility of NIVE for small vessel elasticity imaging was demonstrated in vitro.

  8. Collagen-based scaffolds for tissue engineering of small-diameter blood vessels

    OpenAIRE

    Buttafoco, Laura

    2005-01-01

    Atherosclerotic vascular disease, including peripheral and coronary artery disease, is the main cause of morbidity and mortality in the Western society. Although synthetic blood vessel prostheses are successfully being used for large-diameter vascular reconstructions, until now no functional small-diameter (< 6 mm) artificial vascular graft is available. Autologous veins and arteries are currently being used as vessel substitutes, but limitations in arteries supply and compliance mismatch are...

  9. Assessing the Efficiency of Small-Scale and Bottom Trawler Vessels in Greece

    Directory of Open Access Journals (Sweden)

    Dario Pinello

    2016-07-01

    Full Text Available This study explores the technical and scale efficiency of two types of Greek fishing vessels, small-scale vessels and bottom trawlers, using a bias-corrected input-oriented Data Envelopment Analysis model. Moreover, the associations between efficiency scores and vessel’s and skipper’s characteristics are also explored. The results indicate that small-scale vessels achieve a very low average technical efficiency score (0.42 but a much higher scale efficiency score (0.81. Conversely, bottom trawlers achieve lower scale but higher technical efficiency scores (0.68 and 0.73, respectively. One important finding of this study is that the technical efficiency of small-scale vessels, in contrast to trawlers, is positively associated with the experience of the skipper. In a looser context, it can be said that small-scale fisheries mainly rely on skill, whereas bottom trawlers rely more on technology. This study concludes that there is space for improvement in efficiency, mainly for small-scale vessels, which could allow the achievement of the same level of output by using reduced inputs.

  10. Astrocytic adaptation during cerebral angiogenesis follows the new vessel formation induced through chronic hypoxia in adult mouse cortex

    Science.gov (United States)

    Masamoto, Kazuto; Kanno, Iwao

    2014-03-01

    We examined longitudinal changes of the neuro-glia-vascular unit during cerebral angiogenesis induced through chronic hypoxia in the adult mouse cortex. Tie2-GFP mice in which the vascular endothelial cells expressed green fluorescent proteins (GFP) were exposed to chronic hypoxia, while the spatiotemporal developments of the cortical capillary sprouts and the neighboring astrocytic remodeling were characterized with repeated two-photon microscopy. The capillary sprouts appeared at early phases of the hypoxia adaptation (1-2 weeks), while the morphological changes of the astrocytic soma and processes were not detected in this phase. In the later phases of the hypoxia adaptation (> 2 weeks), the capillary sprouts created a new connection with existing capillaries, and its neighboring astrocytes extended their processes to the newly-formed vessels. The findings show that morphological adaptation of the astrocytes follow the capillary development during the hypoxia adaptation, which indicate that the newly-formed vessels provoke cellular interactions with the neighboring astrocytes to strengthen the functional blood-brain barrier.

  11. Effect of edaravone on favorable outcome in patients with acute cerebral large vessel occlusion: subanalysis of RESCUE-Japan Registry.

    Science.gov (United States)

    Miyaji, Yuki; Yoshimura, Shinichi; Sakai, Nobuyuki; Yamagami, Hiroshi; Egashira, Yusuke; Shirakawa, Manabu; Uchida, Kazutaka; Kageyama, Hirohito; Tomogane, Yusuke

    2015-01-01

    The data of the nationwide prospective registry of acute cerebral large vessel occlusion (LVO; RESCUE-Japan Registry) were analyzed to know the effect of edaravone, a free radical scavenger, on clinical outcome at 90 days after onset. In this registry, patients with acute cerebral LVO admitted within 24 h after onset were prospectively registered. The effect of various factors including endovascular treatment (EVT), intravenous recombinant tissue plasminogen activator (IV rt-PA), and other medication including edaravone on favorable outcome (modified Rankin scale 0-1) was analyzed. Of the 1,454 registered patients, 1,442 patients (99.2%) had the information of edaravone were analyzed. In total, edaravone group had more patients with favorable outcome compared to non-edaravone group (22.9% vs. 13.8%, p = 0.0006). Edaravone increased favorable outcome in patients treated with IV rt-PA (29.4% vs. 11.1%, p = 0.0107), but not with EVT (21.2% vs. 13.9%, p = 0.309). Logistic regression analysis revealed that higher National Institutes of Health Stroke Scale (NIHSS) score on admission [odds ratio (OR) 0.875, 95% confidence interval (CI) 0.858-0.894] and advanced age (OR 0.963, 95%CI 0.952-0.975) were significantly related to unfavorable outcome. In contrast, IV rt-PA (OR 2.489, 95%CI 1.867-3.319), EVT (OR 1.375, 95%CI 1.013-1.865), and edaravone (OR 1.483, 95%CI 1.027-2.143) were significantly associated with favorable outcome. This analysis indicated that IV rt-PA, EVT, and edaravone were effective to obtain favorable outcome in patients with acute LVO. Combination IV rt-PA with edaravone was more effective. PMID:25739433

  12. Prediction of Impaired Performance in Trail Making Test in MCI Patients With Small Vessel Disease Using DTI Data.

    Science.gov (United States)

    Ciulli, Stefano; Citi, Luca; Salvadori, Emilia; Valenti, Raffaella; Poggesi, Anna; Inzitari, Domenico; Mascalchi, Mario; Toschi, Nicola; Pantoni, Leonardo; Diciotti, Stefano

    2016-07-01

    Mild cognitive impairment (MCI) is a common condition in patients with diffuse hyperintensities of cerebral white matter (WM) in T2-weighted magnetic resonance images and cerebral small vessel disease (SVD). In MCI due to SVD, the most prominent feature of cognitive impairment lies in degradation of executive functions, i.e., of processes that supervise the organization and execution of complex behavior. The trail making test is a widely employed test sensitive to cognitive processing speed and executive functioning. MCI due to SVD has been hypothesized to be the effect of WM damage, and diffusion tensor imaging (DTI) is a well-established technique for in vivo characterization of WM. We propose a machine learning scheme tailored to 1) predicting the impairment in executive functions in patients with MCI and SVD, and 2) examining the brain substrates of this impairment. We employed data from 40 MCI patients with SVD and created feature vectors by averaging mean diffusivity (MD) and fractional anisotropy maps within 50 WM regions of interest. We trained support vector machines (SVMs) with polynomial as well as radial basis function kernels using different DTI-derived features while simultaneously optimizing parameters in leave-one-out nested cross validation. The best performance was obtained using MD features only and linear kernel SVMs, which were able to distinguish an impaired performance with high sensitivity (72.7%-89.5%), specificity (71.4%-83.3%), and accuracy (77.5%-80.0%). While brain substrates of executive functions are still debated, feature ranking confirm that MD in several WM regions, not limited to the frontal lobes, are truly predictive of executive functions. PMID:26960231

  13. 脑血管病与继发性癫痫的相关性分析%The relative analysis of cerebral vessel disease and secondary epilepsy

    Institute of Scientific and Technical Information of China (English)

    于子燕; 徐伟丽; 黄小丽

    2001-01-01

    @@Background: CVD is one of reasons of secondary epilepsy, and epilepsy episode is some CVD patients' first symptom, whose state of disease is severe from beginning. Some latent epilepsy can worse the diseases of nerve system existed before and influence its prognosis. Objective:To explore the relationship between cerebral vessel disease and secondary epilepsy. Unit: Nervous Internal Medicine Deparetment of Weihai Municipal Hospital of Shandong .

  14. Regional heterogeneity in the reactivity of equine small pulmonary blood vessels.

    Science.gov (United States)

    Stack, Alice; Derksen, Frederik J; Williams, Kurt J; Robinson, N Edward; Jackson, William F

    2016-03-15

    Regional differences in large equine pulmonary artery reactivity exist. It is not known if this heterogeneity extends into small vessels. The hypothesis that there is regional heterogeneity in small pulmonary artery and vein reactivity to sympathomimetics (phenylephrine and isoproterenol) and a parasympathomimetic (methacholine) was tested using wire myography on small vessels from caudodorsal (CD) and cranioventral (CV) lung of 12 horses [9 mares, 3 geldings, 8.67 ± 0.81 (age ± SE) yr, of various breeds that had never raced]. To study relaxation, vessels were precontracted with U46619 (10(-6) M). Methacholine mechanism of action was investigated using l-nitroarginine methylester (l-NAME, 100 μM) and indomethacin (10 μM). Phenylephrine did not contract any vessels. Isoproterenol relaxed CD arteries more than CV arteries (maximum relaxation 28.18% and 48.67%; Log IC50 ± SE -7.975 ± 0.1327 and -8.033 ± 0.1635 for CD and CV, respectively, P < 0.0001), but not veins. Methacholine caused contraction of CD arteries (maximum contraction 245.4%, Log EC50 ± SE -6.475 ± 0.3341), and relaxation of CV arteries (maximum relaxation 40.14%, Log IC50 ± SE -6.791 ± 0.1954) and all veins (maximum relaxation 50.62%, Log IC50 ± SE -6.932 ± 0.1986) in a nonregion-dependent manner. l-NAME (n = 8, P < 0.0001) and indomethacin (n = 7, P < 0.0001) inhibited methacholine-induced relaxation of CV arteries, whereas indomethacin augmented CD artery contraction (n = 8, P < 0.0001). Our data demonstrate significant regional heterogeneity in small blood vessel reactivity when comparing the CD to the CV region of the equine lung. PMID:26769957

  15. Small intestinal strictures as a complication of mesenteric vessel thrombosis: two case reports

    Directory of Open Access Journals (Sweden)

    Patel Sandeep

    2009-09-01

    Full Text Available Abstract Introduction Small intestinal strictures secondary to mesenteric vessel thrombosis are a rare entity and thus often result in delayed diagnosis. We present two cases of ischaemic small bowel strictures secondary to mesenteric vessel thrombosis, and describe how they were subsequently managed. Case presentation We present two cases of abdominal pain, one acute and one chronic, in which the eventual diagnosis was of bowel strictures secondary to arterial and venous vessel thrombosis. In both patients, a Caucasian male aged 67 and a Caucasian female aged 78, the diagnosis was delayed because of the infrequency of their presentation. Both patients eventually underwent a resection of the affected portion of bowel with primary anastamosis and made uneventful recoveries. Conclusion There are multiple medical and surgical management options for small bowel strictures and these depend on the aetiology of the stricture. Ischaemic small bowel strictures represent a difficult diagnosis and the potential resulting delay may be partially responsible for increased morbidity. Barium small bowel follow-through should be used in making the diagnosis.

  16. Powering Small Satellites with Advanced NiH2 Dependent Pressure Vessel (DPV) Batteries

    OpenAIRE

    Caldwell, Dwight; Fox, Chris; Miller, Lee

    1996-01-01

    The Dependent Pressure Vessel (DPV) nickel-hydrogen (NiH2) design is being developed by Eagle-Picher Industries, Inc. (EPI), as a spacecraft battery for both large and small, military and commercial satellites. The DPV cell design offers high specific energy, energy density and reduced cost, while retaining the established IPV technology flight heritage and database. This advanced design also offers a more efficient mechanical, electrical and thermal cell and battery configuration and a reduc...

  17. In Vivo μPIV Measurements of Blood Flow in Small Vessels of a Rat Model.

    Science.gov (United States)

    Wei, Timothy; Conner, Nadine; Russell, John; Legac, Paul

    2007-11-01

    Ongoing research at the University of Wisconsin Medical School is addressing the effects of perfusion of glottal tissue on voice production. Building on the approach developed by Gharib's group at CalTech for embryonic zebra fish, we have modified μPIV to measure flow in capillaries and small blood vessels in a live rat model. In lieu of seeding particles, the DPIV correlation algorithm tracks the motion of red blood cells moving through these vessels. The methodology will be presented along with a video sequence showing measurements made from muscle tissue laid nominally flat on a microscope stage. Challenges of measurements in three-dimensional geometries, i.e. the throat, will be discussed.

  18. Mathematical Model of Blood Flow in Small Blood Vessel in the Presence of Magnetic Field

    Directory of Open Access Journals (Sweden)

    Rekha Bali

    2011-02-01

    Full Text Available A mathematical model for blood flow in the small blood vessel in the presence of magnetic field is presented in this paper. We have modeled the two phase model for the blood flow consists of a central core of suspended erythrocytes and cell-free layer surrounding the core. The system of differential equations has been solved analytically. We have obtained the result for velocity, flow rate and effective viscosity in presence of peripheral layer and magnetic field .All the result has been obtained and discussed through graphs.

  19. Characterising the grey matter correlates of leukoaraiosis in cerebral small vessel disease

    Directory of Open Access Journals (Sweden)

    Christian Lambert

    2015-01-01

    We demonstrate that SVD severity is associated with regional cortical thinning. Furthermore a quantitative measure of SVD severity (WMH volume can be predicted from grey matter measures, supporting an association between white and grey matter damage. The pattern of cortical thinning and volumetric decline is distinctive for SVD severity compared to ageing. These results, taken together, suggest that there is a phenotypic pattern of atrophy associated with SVD severity.

  20. An in situ optical imaging system for measuring lipid uptake, vessel contraction, and lymph flow in small animal lymphatic vessels

    Science.gov (United States)

    Kassis, Timothy; Weiler, Michael J.; Dixon, J. Brandon

    2012-03-01

    All dietary lipids are transported to venous circulation through the lymphatic system, yet the underlying mechanisms that regulate this process remain unclear. Understanding how the lymphatics functionally respond to changes in lipid load is important in the diagnosis and treatment of lipid and lymphatic related diseases such as obesity, hypercholesterolemia, and lymphedema. Therefore, we sought to develop an in situ imaging system to quantify and correlate lymphatic function as it relates to lipid transport. A custom-built optical set-up provides us with the capability of dual-channel imaging of both high-speed bright-field video and fluorescence simultaneously. This is achieved by dividing the light path into two optical bands. Utilizing high-speed and back-illuminated CCD cameras and post-acquisition image processing algorithms, we have the potential quantify correlations between vessel contraction, lymph flow and lipid concentration of mesenteric lymphatic vessels in situ. Local flow velocity is measured through lymphocyte tracking, vessel contraction through measurements of the vessel walls and lipid uptake through fluorescence intensity tracking of a fluorescent long chain fatty acid analogue, Bodipy FL C16. This system will prove to be an invaluable tool for both scientists studying lymphatic function in health and disease, and those investigating strategies for targeting the lymphatic system with orally delivered drugs.

  1. Characterisation of creep cavitation damage in a stainless steel pressure vessel using small angle neutron scattering

    CERN Document Server

    Bouchard, P J; Treimer, W

    2002-01-01

    Grain-boundary cavitation is the dominant failure mode associated with initiation of reheat cracking, which has been widely observed in austenitic stainless steel pressure vessels operating at temperatures within the creep range (>450 C). Small angle neutron scattering (SANS) experiments at the LLB PAXE instrument (Saclay) and the V12 double-crystal diffractometer of the HMI-BENSC facility (Berlin) are used to characterise cavitation damage (in the size range R=10-2000 nm) in a variety of creep specimens extracted from ex-service plant. Factors that affect the evolution of cavities and the cavity-size distribution are discussed. The results demonstrate that SANS techniques have the potential to quantify the development of creep damage in type-316H stainless steel, and thereby link microstructural damage with ductility-exhaustion models of reheat cracking. (orig.)

  2. Small vessel ischemic disease of the brain and brain metastases in lung cancer patients.

    Directory of Open Access Journals (Sweden)

    Peter J Mazzone

    Full Text Available BACKGROUND: Brain metastases occur commonly in patients with lung cancer. Small vessel ischemic disease is frequently found when imaging the brain to detect metastases. We aimed to determine if the presence of small vessel ischemic disease (SVID of the brain is protective against the development of brain metastases in lung cancer patients. METHODOLOGY/PRINCIPAL FINDINGS: A retrospective cohort of 523 patients with biopsy confirmed lung cancer who had received magnetic resonance imaging of the brain as part of their standard initial staging evaluation was reviewed. Information collected included demographics, comorbidities, details of the lung cancer, and the presence of SVID of the brain. A portion of the cohort had the degree of SVID graded. The primary outcome measure was the portion of study subjects with and without SVID of the brain who had evidence of brain metastases at the time of initial staging of their lung cancer.109 patients (20.8% had evidence of brain metastases at presentation and 345 (66.0% had evidence of SVID. 13.9% of those with SVID and 34.3% of those without SVID presented with brain metastases (p<0.0001. In a model including age, diabetes mellitus, hypertension, hyperlipidemia, and tobacco use, SVID of the brain was found to be the only protective factor against the development of brain metastases, with an OR of 0.31 (0.20, 0.48; p<0.001. The grade of SVID was higher in those without brain metastases. CONCLUSIONS/SIGNIFICANCE: These findings suggest that vascular changes in the brain are protective against the development of brain metastases in lung cancer patients.

  3. Gamma Knife Radiosurgery for Treatment of Cerebral Metastases From Non–Small-Cell Lung Cancer

    International Nuclear Information System (INIS)

    Purpose: To evaluate clinical and physico-dosimetric variables affecting clinical outcome of patients treated with Gamma Knife radiosurgery (GKRS) for brain metastases from non–small cell lung cancer (NSCLC). Methods and Materials: Between 2001 and 2006, 373 patients (298 men and 75 women, median age 65 years) with brain metastases from NSCLC underwent GKRS. All of them had KPS ≥ 60%, eight or fewer brain metastases, confirmed histopathological diagnosis and recent work-up (3. Median marginal dose was 22.5 Gy at 50% isodose.; median 10 Gy and 12 Gy isodose volumes were 30.8 cm3 and 15.8 cm3, respectively. Follow-up with MRI was performed every 3 months. Overall survival data were collected from internal database, telephone interviews, and identifying registries. Results: Mean follow-up after GKRS was 51 months (range, 6 to 96 months); mean overall survival was 14.2 months. Of 373 patients, 29 were alive at time of writing, 104 had died of cerebral progression, and 176 had died of systemic progression. In 64 cases it was not possible to ascertain the cause. Univariate and multivariate analysis were adjusted for the following: RPA class, surgery, WBRT, age, gender, number of lesions, median tumor volume, median peripheral dose, and 10 Gy and 12 Gy volumes. Identified RPA class and overall tumor volume >5 cc were the only two covariates independently predictive of overall survival in patients who died of cerebral progression. Conclusions: Global volume of brain disease should be the main parameter to consider for performing GKRS, which is a first-line therapy for patient in good general condition and controlled systemic disease.

  4. Structural characterization of the human cerebral myelin sheath by small angle x-ray scattering

    Science.gov (United States)

    DeFelici, M.; Felici, R.; Ferrero, C.; Tartari, A.; Gambaccini, M.; Finet, S.

    2008-10-01

    Myelin is a multi-lamellar membrane surrounding neuronal axons and increasing their conduction velocity. When investigated by small-angle x-ray scattering (SAXS), the lamellar quasi-periodical arrangement of the myelin sheath gives rise to distinct peaks, which allow the determination of its molecular organization and the dimensions of its substructures. In this study we report on the myelin sheath structural determination carried out on a set of human brain tissue samples coming from surgical biopsies of two patients: a man around 60 and a woman nearly 90 years old. The samples were extracted either from white or grey cerebral matter and did not undergo any manipulation or chemical-physical treatment, which could possibly have altered their structure, except dipping them into a formalin solution for their conservation. Analysis of the scattered intensity from white matter of intact human cerebral tissue allowed the evaluation not only of the myelin sheath periodicity but also of its electronic charge density profile. In particular, the thicknesses of the cytoplasm and extracellular regions were established, as well as those of the hydrophilic polar heads and hydrophobic tails of the lipid bilayer. SAXS patterns were measured at several locations on each sample in order to establish the statistical variations of the structural parameters within a single sample and among different samples. This work demonstrates that a detailed structural analysis of the myelin sheath can also be carried out in randomly oriented samples of intact human white matter, which is of importance for studying the aetiology and evolution of the central nervous system pathologies inducing myelin degeneration.

  5. Irradiation Induced Defect Characterization in Reactor Pressure Vessel Steel by Small Angle Neutron Scattering

    Science.gov (United States)

    Han, Yougn-Soo; Shin, Eun-Joo; Lee, Chang-Hee; Park, Duck-Gun

    The degradation of the mechanical properties of the RPV (Reactor Pressure Vessel) steel during an irradiation in a nuclear power plant is closely related to the irradiation induced defects. The size of these defects is known to be a few nanometer, and the small angle neutron scattering technique is regarded as the best non destructive technique to characterize the nano sized inhomogeneities in bulk samples. The investigated the RPV steel has been used in YeongKwang nuclear power plant at Korea and the Cu content of the RPV steel is 0.06 wt%. The RPV steel was irradiated in the HANARO reactor at KAERI. The small angle neutron scattering experiments were performed by the SANS instrument in the HANARO reactor. The nano sized irradiation induced defects were quantitatively analyzed by SANS and the type of the irradiation induced defects was discussed in detail. The relation between irradiation induced defects and the yield strength was investigated. The characteristics of irradiation induced defects in low Cu containing RPV steel were discussed.

  6. BOLD fMRI in the white matter as a marker of aging and small vessel disease.

    Directory of Open Access Journals (Sweden)

    Ilia Makedonov

    Full Text Available PURPOSE: Determine whether white matter signal fluctuation on T2* weighted BOLD contrast images are associated with aging and cerebral small vessel disease (SVD. METHODOLOGY: Resting state BOLD data were collected with a 250 ms repetition time (TR to achieve unaliased, ungated cardiac sampled BOLD (cs-BOLD images on 11 young adult controls, 10 healthy older adult controls and 7 adults with extensive white matter hyperintensities (WMH from SVD. Tissue classes (WM and GM were segmented on T1 images. WMH were identified on FLAIR images in the SVD group. Raw physiological noise (σphysio and cardiac pulsatility (i.e. fluctuations at the cardiac frequency were calculated voxel wise and group differences were tested by ANOVA. It was also possible to calculate σphysio in 2s TR cardiac aliased whole-brain BOLD (wb-BOLD data (N = 84 obtained from the International Consortium for Brain Mapping. RESULTS: CS-BOLD metrics showed an aging and SVD effects (p<0.0005. Covariates such as thermal noise, WM volume and partial volume did not influence the significant aging effect seen on the cardiac pulsatility metric (p<0.017 but did influence the σphysio (p = 0.184. As a verification of the cs-BOLD findings, the wb-BOLD also showed a linear aging effect of σphysio in WM. In the SVD adults, cardiac pulsatility and σphysio were lower in WMH regions compared to normal appearing white matter (NAWM regions (p<0.0013 and p<0.002, respectively. Cardiac pulsatility was better able to distinguish WMH regions from NAWM than σphysio as measured by effect size (Cohen's d 2.2 and 0.88, respectively. CONCLUSION: NAWM was found to have graded increases in cardiac pulsations due to age and SVD, independently. Within SVD participants, WMH lesions had reduced physiological noise compared to NAWM. Cardiac pulsatility in resting BOLD data may provide a complementary dynamic measure of WM integrity to add to static FLAIR anatomical images.

  7. Association of apolipoprotein E gene polymorphism with small-vessel lesions and stroke type in moyamoya disease: a preliminary study.

    Science.gov (United States)

    Jang, Dong-Kyu; Huh, Pil Woo; Lee, Kwan-Sung

    2016-06-01

    OBJECT The present study was conducted to investigate whether microbleeds or microinfarcts are associated with apolipoprotein E (APOE) gene polymorphisms in patients with moyamoya disease (MMD), and if so, whetherAPOE gene polymorphisms are also associated with stroke type in patients with MMD. METHODS This cross-sectional, multicenter study included 86 consecutive patients with MMD who underwent T2*-weighted gradient echo or susceptibility-weighted MR imaging and 83 healthy control volunteers. Baseline clinical and radiological characteristics were recorded at diagnosis, and inter- and intragroup differences in the APOE genotypes were assessed. Multivariate binary logistic regression models were used to determine the association factors for small-vessel lesions (SVLs) and hemorrhagic presentation in patients with MMD. RESULTS There was no difference in APOE gene polymorphism and the incidence of SVLs between patients with MMD and healthy controls (p > 0.05). In the MMD group, 7 (8.1%) patients had microbleeds and 32 (37.2%) patients had microinfarcts. Microbleeds were more frequently identified in patients with hemorrhagic-type than in nonhemorrhagictype MMD (p = 0.003). APOE genotypes differed according to the presence of microbleeds (p = 0.024). APOE ε2 or ε4 carriers also experienced microbleeds more frequently than APOE ε3/ε3 carriers (p = 0.013). In the multivariate regression analysis in patients with MMD, microbleeds were significantly related to APOE ε2 or ε4 carrier status (OR 7.86; 95% CI1.20-51.62; p = 0.032) and cerebral aneurysm (OR 17.31; 95% CI 2.09-143.57; p = 0.008). Microinfarcts were independently associated with hypertension (OR 3.01; 95% CI 1.05-7.86; p = 0.007). Hemorrhagic presentation was markedly associated with microbleeds (OR 10.63; 95% CI 1.11-102.0; p = 0.041). CONCLUSIONS These preliminary results did not show a difference in APOE gene polymorphisms between patients with MMD and healthy persons. However, they imply that APOE

  8. VISIR-I: small vessels, least-time nautical routes using wave forecasts

    Directory of Open Access Journals (Sweden)

    G. Mannarini

    2015-09-01

    Full Text Available A new numerical model for the on-demand computation of optimal ship routes based on sea-state forecasts has been developed. The model, named VISIR (discoVerIng Safe and effIcient Routes is designed to support decision-makers when planning a marine voyage. The first version of the system, VISIR-I, considers medium and small motor vessels with lengths of up to a few tens of meters and a displacement hull. The model is made up of three components: the route optimization algorithm, the mechanical model of the ship, and the environmental fields. The optimization algorithm is based on a graph-search method with time-dependent edge weights. The algorithm is also able to compute a voluntary ship speed reduction. The ship model accounts for calm water and added wave resistance by making use of just the principal particulars of the vessel as input parameters. The system also checks the optimal route for parametric roll, pure loss of stability, and surfriding/broaching-to hazard conditions. Significant wave height, wave spectrum peak period, and wave direction forecast fields are employed as an input. Examples of VISIR-I routes in the Mediterranean Sea are provided. The optimal route may be longer in terms of miles sailed and yet it is faster and safer than the geodetic route between the same departure and arrival locations. Route diversions result from the safety constraints and the fact that the algorithm takes into account the full temporal evolution and spatial variability of the environmental fields.

  9. A miniature research vessel: A small-scale ocean-exploration demonstration of geophysical methods

    Science.gov (United States)

    Howell, S. M.; Boston, B.; Sleeper, J. D.; Cameron, M. E.; Togia, H.; Anderson, A.; Sigurdardottir, T. D.; Tree, J. P.

    2015-12-01

    Graduate student members of the University of Hawaii Geophysical Society have designed a small-scale model research vessel (R/V) that uses sonar to create 3D maps of a model seafloor in real-time. A pilot project was presented to the public at the School of Ocean and Earth Science and Technology's (SOEST) Biennial Open House weekend in 2013 and, with financial support from the Society of Exploration Geophysicists and National Science Foundation, was developed into a full exhibit for the same event in 2015. Nearly 8,000 people attended the two-day event, including children and teachers from Hawaii's schools, home school students, community groups, families, and science enthusiasts. Our exhibit demonstrates real-time sonar mapping of a cardboard volcano using a toy size research vessel on a programmable 2-dimensional model ship track suspended above a model seafloor. Ship waypoints were wirelessly sent from a Windows Surface tablet to a large-touchscreen PC that controlled the exhibit. Sound wave travel times were recorded using an ultrasonic emitter/receiver attached to an Arduino microcontroller platform and streamed through a USB connection to the control PC running MatLab, where a 3D model was updated as the ship collected data. Our exhibit demonstrates the practical use of complicated concepts, like wave physics, survey design, and data processing in a way that the youngest elementary students are able to understand. It provides an accessible avenue to learn about sonar mapping, and could easily be adapted to talk about bat and marine mammal echolocation by replacing the model ship and volcano. The exhibit received an overwhelmingly positive response from attendees and incited discussions that covered a broad range of earth science topics.

  10. VISIR-I: small vessels - least-time nautical routes using wave forecasts

    Science.gov (United States)

    Mannarini, Gianandrea; Pinardi, Nadia; Coppini, Giovanni; Oddo, Paolo; Iafrati, Alessandro

    2016-05-01

    A new numerical model for the on-demand computation of optimal ship routes based on sea-state forecasts has been developed. The model, named VISIR (discoVerIng Safe and effIcient Routes) is designed to support decision-makers when planning a marine voyage. The first version of the system, VISIR-I, considers medium and small motor vessels with lengths of up to a few tens of metres and a displacement hull. The model is comprised of three components: a route optimization algorithm, a mechanical model of the ship, and a processor of the environmental fields. The optimization algorithm is based on a graph-search method with time-dependent edge weights. The algorithm is also able to compute a voluntary ship speed reduction. The ship model accounts for calm water and added wave resistance by making use of just the principal particulars of the vessel as input parameters. It also checks the optimal route for parametric roll, pure loss of stability, and surfriding/broaching-to hazard conditions. The processor of the environmental fields employs significant wave height, wave spectrum peak period, and wave direction forecast fields as input. The topological issues of coastal navigation (islands, peninsulas, narrow passages) are addressed. Examples of VISIR-I routes in the Mediterranean Sea are provided. The optimal route may be longer in terms of miles sailed and yet it is faster and safer than the geodetic route between the same departure and arrival locations. Time savings up to 2.7 % and route lengthening up to 3.2 % are found for the case studies analysed. However, there is no upper bound for the magnitude of the changes of such route metrics, which especially in case of extreme sea states can be much greater. Route diversions result from the safety constraints and the fact that the algorithm takes into account the full temporal evolution and spatial variability of the environmental fields.

  11. Four-vessel occlusion model using aged male Wistar rats: a reliable model to resolve the discrepancy related to age in cerebral ischemia research.

    Science.gov (United States)

    Ancer-Rodríguez, Jesús; Villarreal-Silva, Eliud Enrique; Salazar-Ybarra, Rodolfo Amador; Quiroga-García, Oscar; Rodríguez-Rocha, Humberto; García-García, Aracely; Morales-Avalos, Rodolfo; Morales-Gómez, Jesús Alberto; Quiroga-Garza, Alejandro; Saucedo-Cárdenas, Odila; Xu, Zao Cheng; Elizondo-Omaña, Rodrigo Enrique; Martínez-Ponce-de-León, Angel Raymundo; Guzmán-López, Santos

    2016-06-01

    Animal models of cerebral ischemia have typically been established and performed using young animals, even though cerebral ischemia (CI) affects primarily elderly patients. This situation represents a discrepancy that complicates the translation of novel therapeutic strategies for CI. Models of transient global CI using aged animals have demonstrated an apparent neuroprotective effect on CA1 hippocampal neurons; however, this effect is not completely understood. Our study used a model in which young (3-6 months) and aged (18-21 months) male Wistar rats were subjected to 15 min of transient global CI using the four-vessel occlusion (4 VO) model. We determined that the 4 VO model can be performed on aged rats with a slight increase in mortality rate. In aged rats, the morphological damage was completely established by the 4th day after reperfusion, displaying no difference from their younger counterparts. These results demonstrated the lack of a neuroprotective effect of aging on CA1 hippocampal neurons in aged male Wistar rats. This study determined and characterized the morphological damage to the CA1 area after 15 min of 4 VO in aged male Wistar rats, validating the use of this model in CI and aging research. PMID:25966656

  12. Thermal-hydraulic analysis for reactor vessel upper-head small break LOCA using SPACE code

    International Nuclear Information System (INIS)

    A small break loss of coolant accident (SBLOCA) in upper-head of a reactor vessel at OPR1000 was analyzed using SPACE code, which is an advanced thermal-hydraulic system analysis code developed by the Korea nuclear industry. To assess the capability of SPACE code, upper-head SBLOCA with full plant safeguards was simulated, and compared with results of MARS-KS code. Reasonably good agreement with major thermal-hydraulic parameters was obtained by analyzing the transient behavior. Based on the observed thermal-hydraulic features, simulations with the failure of partial plant safeguards were conducted to analyze the safety and performance of OPR1000. Effects of failure to scram and high-pressure safety injection (HPSI) were investigated, and safety assessment was evaluated according to operator actions. Comparative study without any emergency core cooling systems (ECCS) was also conducted to judge the severity of the break location. From the results, this indicated that SPACE code has capabilities to simulate upper-head SBLOCA, and OPR1000 was evaluated to have sufficient safety margin with the application of proper emergency operating procedures.

  13. Containment vs confinement trade study, small HTGR plant PCRV [prestressed concrete reactor vessel] concept

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1985-03-01

    This trade study has been conducted to evaluate the differences between four different HTGR nuclear power plants. All of the plants use a prestressed concrete reactor vessel (PCRV) to house the core and steam generation equipment. The reactor uses LEU U/Th fuel in prismatic carbon blocks. All plant concepts meet the utility/user requirements established for small HTGR plants. All plants will be evaluated with regard to their ability to produce safe, economical power to satisfy Goals 1, 2, and 3 of the HTGR program and by meeting the MUST criteria established in the concept evaluation plan. Capital costs for each plant were evaluated on a differential cost basis. These costs were developed according to the ``NUS`` code of accounts as defined in the Cost Estimating and Control Procedure, HP-20901. Accounts that were identical in scope for all four plants were not used for the comparison. Table 1-1 is a list of capital cost accounts that were evaluated for each plant.

  14. Small angle neutron scattering study of radiation damage in reactor vessel materials

    International Nuclear Information System (INIS)

    Complete text of publication follows. Nuclear radiation provides important changes in the microstructure of metallic components of nuclear power plant and research reactors, influencing their mechanical properties. The investigation of this problem has primary interest for the safety and life-time of such nuclear installations. For the characterisation of this kind of nanostructures small angle neutron scattering technique is a very useful tool. Experiments were carried out on samples of irradiated reactor vessel material and welded components of VVER-440 type reactors on the SANS instrument at the Budapest Research Reactor. In these measurements irradiated as well as non-irradiated samples were compared and magnetic field was applied for viewing the magnetic structure effects of the materials. A clear modification of the structure due to irradiation was obtained. The data sets were processed with the ITP92 code, the inverse Fourier transform programme of O. Glatter [1]. Our microstructural observations fit well to the hardness test results. [2]. (author) [1] O. Glatter (1997) J. Appl. Cryst. 10, 415-421.; [2] M. Grosse, J. Boehmert, H.W. Viehrig (1994) Journal of Nuclear Materials 211, 177-180

  15. Thermal-hydraulic analysis for reactor vessel upper-head small break LOCA using SPACE code

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Minhee; Kim, Seyun [Korea Hydro and Nuclear Power Co., Central Research Inst., Daejeon (Korea, Republic of)

    2015-08-15

    A small break loss of coolant accident (SBLOCA) in upper-head of a reactor vessel at OPR1000 was analyzed using SPACE code, which is an advanced thermal-hydraulic system analysis code developed by the Korea nuclear industry. To assess the capability of SPACE code, upper-head SBLOCA with full plant safeguards was simulated, and compared with results of MARS-KS code. Reasonably good agreement with major thermal-hydraulic parameters was obtained by analyzing the transient behavior. Based on the observed thermal-hydraulic features, simulations with the failure of partial plant safeguards were conducted to analyze the safety and performance of OPR1000. Effects of failure to scram and high-pressure safety injection (HPSI) were investigated, and safety assessment was evaluated according to operator actions. Comparative study without any emergency core cooling systems (ECCS) was also conducted to judge the severity of the break location. From the results, this indicated that SPACE code has capabilities to simulate upper-head SBLOCA, and OPR1000 was evaluated to have sufficient safety margin with the application of proper emergency operating procedures.

  16. The association of cerebral palsy and death with small-for-gestational-age birthweight in preterm neonates by individualized and population-based percentiles.

    LENUS (Irish Health Repository)

    Grobman, William A

    2013-10-01

    The objective of the study was to determine whether an individualized growth standard (IS) improves the identification of preterm small-for-gestational-age (SGA) neonates at risk of developing moderate\\/severe cerebral palsy (CP) or death.

  17. Small vessel disease and cognitive impairment: The relevance of central network connections.

    Science.gov (United States)

    Reijmer, Yael D; Fotiadis, Panagiotis; Piantoni, Giovanni; Boulouis, Gregoire; Kelly, Kathleen E; Gurol, Mahmut E; Leemans, Alexander; O'Sullivan, Michael J; Greenberg, Steven M; Viswanathan, Anand

    2016-07-01

    Central brain network connections greatly contribute to overall network efficiency. Here we examined whether small vessel disease (SVD) related white matter alterations in central brain network connections have a greater impact on executive functioning than alterations in non-central brain network connections. Brain networks were reconstructed from diffusion-weighted MRI scans in 72 individuals (75 ± 8 years) with cognitive impairment and SVD on MRI. The centrality of white matter connections in the network was defined using graph theory. The association between the fractional anisotropy (FA) of central versus non-central connections, executive functioning, and markers of SVD was evaluated with linear regression and mediation analysis. Lower FA in central network connections was more strongly associated with impairment in executive functioning than FA in non-central network connections (r = 0.41 vs. r = 0.27; P 50%-10% connections). Higher SVD burden was associated with lower FA in central as well as non-central network connections. However, only central network FA mediated the relationship between white matter hyperintensity volume and executive functioning [change in regression coefficient after mediation (95% CI): -0.15 (-0.35 to -0.02)]. The mediation effect was not observed for FA alterations in non-central network connections [-0.03 (-0.19 to 0.04)]. These findings suggest that the centrality of network connections, and thus their contribution to global network efficiency, appears to be relevant for understanding the relationship between SVD and cognitive impairment. Hum Brain Mapp 37:2446-2454, 2016. © 2016 Wiley Periodicals, Inc. PMID:27004840

  18. A multi-scale tensor voting approach for small retinal vessel segmentation in high resolution fundus images.

    Science.gov (United States)

    Christodoulidis, Argyrios; Hurtut, Thomas; Tahar, Houssem Ben; Cheriet, Farida

    2016-09-01

    Segmenting the retinal vessels from fundus images is a prerequisite for many CAD systems for the automatic detection of diabetic retinopathy lesions. So far, research efforts have concentrated mainly on the accurate localization of the large to medium diameter vessels. However, failure to detect the smallest vessels at the segmentation step can lead to false positive lesion detection counts in a subsequent lesion analysis stage. In this study, a new hybrid method for the segmentation of the smallest vessels is proposed. Line detection and perceptual organization techniques are combined in a multi-scale scheme. Small vessels are reconstructed from the perceptual-based approach via tracking and pixel painting. The segmentation was validated in a high resolution fundus image database including healthy and diabetic subjects using pixel-based as well as perceptual-based measures. The proposed method achieves 85.06% sensitivity rate, while the original multi-scale line detection method achieves 81.06% sensitivity rate for the corresponding images (pbased measure, the proposed method improves the detection of the vasculature by 7.8% against the original multi-scale line detection method (p<0.05). PMID:27341026

  19. Mass optimization of a small pressure vessel using metal/FRP (fiber reinforced polymers) hybrid structures

    International Nuclear Information System (INIS)

    In hybrid pressure vessels, composite (Fiber) is wound over a metallic liner (Steel/Aluminum) in hoop direction. In this concept of hybrid pressure vessel structure, metallic liner takes all the axial loads and fiber reinforced polymers (FRP/sub s/) takes load in circumferential (Hoop) direction. Hybrid structures combine the relatively high shear stiffness and ductility of metal alloy with high specific stiffness, strength and fatigue properties of FRP/sub s/. The relatively simple methods for producing hybrid structures circumvent the need for the complex and expensive equipment that is used for advanced composites processing. This paper presents an efficient way of designing a hybrid pressure vessel where prime concern is weight reduction over an equivalent aluminum structure and investigates various methodologies regarding combinations of metals and FRP/sub s/ for optimization of a given pressure vessel. For this purpose we adopted two different methods of simulation one is computer simulation using ANSYS and other is experimental verification by hydrostatic testing of manufactured pressure vessel. Two different pressure vessels one with aluminum liner and other with steel liner were fabricated. Kevlar 49/epoxy was wrapped around the liners in hoop direction. Both the pressure vessels were put into hydrostatic test. Strains were measured during the test and then converted into corresponding stresses. Results of hydrostatic test were quite in favor of the ANSYS results. In this way we have successfully designed, manufactured and tested the Hybrid pressure vessel saving almost 40% weight in case of aluminum liner and 43.6% in case of steel liner. (author)

  20. MR vascular fingerprinting: A new approach to compute cerebral blood volume, mean vessel radius, and oxygenation maps in the human brain.

    Science.gov (United States)

    Christen, T; Pannetier, N A; Ni, W W; Qiu, D; Moseley, M E; Schuff, N; Zaharchuk, G

    2014-04-01

    In the present study, we describe a fingerprinting approach to analyze the time evolution of the MR signal and retrieve quantitative information about the microvascular network. We used a Gradient Echo Sampling of the Free Induction Decay and Spin Echo (GESFIDE) sequence and defined a fingerprint as the ratio of signals acquired pre- and post-injection of an iron-based contrast agent. We then simulated the same experiment with an advanced numerical tool that takes a virtual voxel containing blood vessels as input, then computes microscopic magnetic fields and water diffusion effects, and eventually derives the expected MR signal evolution. The parameter inputs of the simulations (cerebral blood volume [CBV], mean vessel radius [R], and blood oxygen saturation [SO2]) were varied to obtain a dictionary of all possible signal evolutions. The best fit between the observed fingerprint and the dictionary was then determined by using least square minimization. This approach was evaluated in 5 normal subjects and the results were compared to those obtained by using more conventional MR methods, steady-state contrast imaging for CBV and R and a global measure of oxygenation obtained from the superior sagittal sinus for SO2. The fingerprinting method enabled the creation of high-resolution parametric maps of the microvascular network showing expected contrast and fine details. Numerical values in gray matter (CBV=3.1±0.7%, R=12.6±2.4μm, SO2=59.5±4.7%) are consistent with literature reports and correlated with conventional MR approaches. SO2 values in white matter (53.0±4.0%) were slightly lower than expected. Numerous improvements can easily be made and the method should be useful to study brain pathologies. PMID:24321559

  1. About a mechanism of the influence of shear stress for viscosity of the blood in vessels of small diameter

    OpenAIRE

    Катюхин, Лев Николаевич

    2014-01-01

    It is proposed a physiological and experimentally confirmed explanation of Fåhraeus-Lindqvist-effect in capillaries using the profile analyses of osmotic deformability of red blood cells. It was shown the dose-dependent change of the erythrocytes deformability in the stage of isotropic spheres after forming artificial water pores (nystatin) and occlusion (PbCl2) of available pores. The Sigma-effect reducing of hematocrit and viscosity in a shear flow of blood through the vessels of a small di...

  2. Gore-Tex small-vessel angioplasty: A suitable substitute for the use of autogenous saphenous vein grafts

    OpenAIRE

    Garcia-Rinaldi, Raul; Rea, John E.; Gallagher, Michael W.; Laevsky, Marlene J.; Ogburn, Michael; Porter, Robert H.

    1980-01-01

    Autogenous saphenous vein has been the material of choice for small-vessel angioplasty and for circulatory access graft reconstruction. In an effort to conserve autogenous saphenous vein, we used expanded polytetrafluoroethylene (PTFE) grafts in 45 patients over a 12-month period. We used Gore-Tex* to reconstruct 17 circulatory access grafts, 16 carotid arteries, two brachial arteries, seven femoral arteries, and three popliteal anterior or posterior tibial arteries. The indications for recon...

  3. Quantitative assessment of cross-sectional area of small pulmonary vessels in patients with COPD using inspiratory and expiratory MDCT

    Energy Technology Data Exchange (ETDEWEB)

    Matsuura, Yukiko, E-mail: matsuyuki_future@yahoo.co.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Kawata, Naoko, E-mail: chumito_03@yahoo.co.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Yanagawa, Noriyuki, E-mail: yanagawa@ho.chiba-u.ac.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Sugiura, Toshihiko, E-mail: sugiura@js3.so-net.ne.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Sakurai, Yoriko, E-mail: yoliri@nifty.com [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Sato, Misuzu, E-mail: mis_misuzu@yahoo.co.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Iesato, Ken, E-mail: iesato_k@yahoo.co.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Terada, Jiro, E-mail: jirotera@chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Sakao, Seiichiro, E-mail: sakao@faculty.chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Tada, Yuji, E-mail: ytada@faculty.chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Tanabe, Nobuhiro, E-mail: ntanabe@faculty.chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Suzuki, Yoichi, E-mail: ysuzuki@faculty.chiba-u.jp [Department of public Health, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan); Tatsumi, Koichiro, E-mail: tatsumi@faculty.chiba-u.jp [Department of Respirology, Graduate School of Medicine, Chiba University, Chiba 260-8670 Japan (Japan)

    2013-10-01

    Objectives: Structural and functional changes in pulmonary vessels are prevalent at the initial stages of chronic obstructive pulmonary disease (COPD). These vascular alterations can be assessed using cross-sectional area (CSA) of small pulmonary vessels. However, neither in non-COPD smokers nor in COPD patients it has been defined whether the structural changes of pulmonary vessels detected by paired inspiratory and expiratory CT scans are associated with emphysematous changes. We quantified the CSA and low attenuation area (LAA) and evaluated the changes in these parameters in the inspiratory and expiratory phases. Materials and methods: Fifty consecutive non-COPD smokers and COPD patients were subjected to multi detector-row CT and the percentage of vessels with a CSA less than 5 mm{sup 2} as well as the percentage LAA for total lung area (%CSA < 5, %LAA, respectively) were calculated. Results: The %CSA < 5 correlated negatively with %LAA. The %CSA < 5 was lower in COPD patients with emphysema as compared with non-COPD smokers and COPD patients with or without mild emphysema. In addition, the %CSA < 5 was lower in the no/mild emphysema subgroup as compared with non-COPD smokers. The respiratory phase change of %CSA < 5 in COPD patients was greater than that in non-COPD smokers. Conclusion: The percentage of small pulmonary vessels decreased as emphysematous changes increase, and this decrease was observed even in patients with no/mild emphysema. Furthermore, respiratory phase changes in CSA were higher in COPD patients than in non-COPD smokers.

  4. Quantitative assessment of cross-sectional area of small pulmonary vessels in patients with COPD using inspiratory and expiratory MDCT

    International Nuclear Information System (INIS)

    Objectives: Structural and functional changes in pulmonary vessels are prevalent at the initial stages of chronic obstructive pulmonary disease (COPD). These vascular alterations can be assessed using cross-sectional area (CSA) of small pulmonary vessels. However, neither in non-COPD smokers nor in COPD patients it has been defined whether the structural changes of pulmonary vessels detected by paired inspiratory and expiratory CT scans are associated with emphysematous changes. We quantified the CSA and low attenuation area (LAA) and evaluated the changes in these parameters in the inspiratory and expiratory phases. Materials and methods: Fifty consecutive non-COPD smokers and COPD patients were subjected to multi detector-row CT and the percentage of vessels with a CSA less than 5 mm2 as well as the percentage LAA for total lung area (%CSA < 5, %LAA, respectively) were calculated. Results: The %CSA < 5 correlated negatively with %LAA. The %CSA < 5 was lower in COPD patients with emphysema as compared with non-COPD smokers and COPD patients with or without mild emphysema. In addition, the %CSA < 5 was lower in the no/mild emphysema subgroup as compared with non-COPD smokers. The respiratory phase change of %CSA < 5 in COPD patients was greater than that in non-COPD smokers. Conclusion: The percentage of small pulmonary vessels decreased as emphysematous changes increase, and this decrease was observed even in patients with no/mild emphysema. Furthermore, respiratory phase changes in CSA were higher in COPD patients than in non-COPD smokers

  5. Cerebrovascular ischemic changes associated with fetal posterior cerebral artery- descriptive retrospective study with magnetic resonance imaging and angiography of brain

    Directory of Open Access Journals (Sweden)

    Venkatraman Indiran

    2016-04-01

    Full Text Available Objectives: Circle of Willis, the main collateral pathway for cerebral circulation, is complete in only a portion of the population. There are many variations in the Circle of Willis. Fetal posterior cerebral artery, which is defined as posterior cerebral artery arising from internal carotid artery, is a common variant of the Circle of Willis. Though association between the fetal posterior cerebral artery and ischemia have been studied, no specific study has been conducted in the Indian population. We aim to identify the incidence of small and large vessel strokes in patients with fetal posterior cerebral artery using Magnetic Resonance Imaging (MRI and Magnetic Resonance Angiography (MRA of brain in the Indian population. Materials and methods: We retrospectively reviewed MR angiographies of the brain performed in our institution, in order to assess the posterior cerebral circulation and its association with small ischemic changes and large vessel strokes. Results: 92 of the 140 patients (65% with fetal posterior cerebral artery (PCA had small vessel ischemic changes. 72 patients (51.4% had large vessel infarcts in any of the vascular territories. 35% of the patients included in this study showed infarcts in the middle cerebral artery (MCA territory and 15 % showed infarcts in the PCA territory. Conclusion: Higher incidence of MCA infarcts in our study probably suggests that PCA cannot aid in collateral formation cases of reduced flow across the internal carotid artery and that fetal PCA could be an important risk factor in cerebrovascular ischemic diseases.

  6. Displasia fibro-muscular de vasos cerebrais: relato de sete casos Fibromuscular dysplasia of cerebral vessels: report of seven cases

    Directory of Open Access Journals (Sweden)

    Ápio Cláudio M. Antunes

    1974-06-01

    Full Text Available Os autores apresentam sete casos de displasia fibro-muscular (DFM, sendo seis deles na artéria carótida e um na artéria vertebral, estudados pelas correspondentes angiografias. São relatadas as histórias clínicas que, em cinco pacientes, são de acidente vascular cerebral isquêmico e, em dois, de hemorragia sub-aracnóide por rotura de aneurisma. Dois pacientes foram à cirurgia: um deles sofreu ligadura de carótida primitiva e outro sofreu endarterectomia para retirada de placa de ateroma da artéria carótida contralateral a aquela com DFM. Finalmente é feita breve discussão sobre a referida patologia, quadro clínico, dignóstico e tratamento, sendo ressaltada a importância do estudo angiográfico carotídeo e vertebral quando encontrada DFM em outro território vascular.Seven cases of fibromuscular dysplasia, six of them of the carotid artery and one of the vertebral artery studied by angiography are reported. The clinical histories have been of ischemic cerebro-vascular accident in five patients and of subarachnoidal hemorrhage dependent on ruptured aneurism in the others. Two patients underwent surgery: a primitive carotid ligation in one and, in the other, an endarterectomy for ressection of an atheroma plaque of the contralateral carotid artery. The symptomatology, diagnosis and treatment are discussed, emphasizing the importance of the vertebral and carotid angiographic study in the cases in which there is a diagnosis of fibromuscular dysplasia in any other vascular territory.

  7. Sporadic Cerebral Amyloid Angiopathy: Pathophysiology, Neuroimaging Features, and Clinical Implications.

    Science.gov (United States)

    Boulouis, Gregoire; Charidimou, Andreas; Greenberg, Steven M

    2016-06-01

    Sporadic cerebral amyloid angiopathy is a small vessel disorder defined pathologically by progressive amyloid deposition in the walls of cortical and leptomeningeal vessels resulting from disruption of a complex balance between production, circulation, and clearance of amyloid-β peptide (Aβ) in the brain. Cerebral amyloid angiopathy is a major cause of lobar symptomatic intracerebral hemorrhage, transient focal neurologic episodes, and a key contributor to vascular cognitive impairment. The mechanisms and consequences of amyloid-β deposition at the pathological level and its neuroimaging manifestations, clinical consequences, and implications for patient care are addressed in this review. PMID:27214698

  8. Activated conduction by small incision and moderate stimulation for treatment of cerebral palsy in 182 cases

    Institute of Scientific and Technical Information of China (English)

    Wenying Wang; Jianhua Shi; Mingjiang Yu; Dazhi Zhang

    2006-01-01

    BACKGROUND: Internationally, methods to treat cerebral palsy (CP) are basically the same, including correction of deformity with orthopaedic operation, selective posterior rhizotomy(SPR), rehabilitation therapy and so on. Domestic methods to treat CP are basically close to the international methods. Traditional Chinese medical therapies, such as, acupuncture and moxibustion, acupoint injection, massage and so on, also have good curative effects.OBJECTIVE: To observe the effect of activated conduction by small incision and moderate stimulation (ACSIMS) on limb function and living ability in patients with spastic CP at different degrees. DESIGN: Retrospective case analysis.SETTING: Department of Medical Education, Shanxi Medical College for Continuing Education. PARTICIPANTS: A total of 182 patients with CP, including 97 males and 85 females, aged 3 to 23 years, who received treatment in Beijing Haidian District Diaoyutai Hospital during October 1996 to September 2005, were involved in this trial. The involved patients met the diagnostic criteria proposed in 2004 National Special Seminar of Cerebral Palsy. According to typing criteria of CP purposed in 1990 Brioni International Conference, the involved patients were typed: 117 with spastic CP, 14 with involuntary movement CP, 19 with defective coordination CP, 5 with hypotonia CP and 27 with mixed type CP. The guardians of underage patients and adult patients themselves were all informed of the therapeutic regimens. METHODS: ①According to CP typing assessment quantitative criteria of Li, the involved patients were assigned from limb position, daily living and movement 3 aspects: mild 23, moderate 75, severe 62 and extremely severe 22. ② Operation methods: The lower limb of moderate spastic CP patient was taken as an example. A median incision or paramedian incision was made between L2 and S1, and it was also the first incision in lower limb. The secorid incision was made at the center of buttock or at the

  9. Preliminary results of an investigation of the structure of pressure vessel steels by small angle neutron scattering

    International Nuclear Information System (INIS)

    Small angle neutron scattering has been used to investigate several irradiation-hardened pressure vessel steels. The neutron scattering produced by scattering centres of approx. 2 nm diameter was enhanced but that from microscopically resolvable objects >= 10 nm diameter was unchanged after fast neutron irradiation to 1017 to 1019 n/cm2 at 180 to 290 deg C. Enhanced scattering was proportional to the copper impurity content in Magnox pressure vessel steels; in PWR steels the enhancement was related primarily to copper content but was also affected by nickel and other elements. These observations support ideas attributing irradiation-strengthening to precipitation of copper particles or to increasing numbers of copper-vacancy complexes. However positive identification of the scattering centres using magnetic methods has not been successful so far. (author)

  10. Morphological changes in small pulmonary vessels are associated with severe acute exacerbation in chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Yoshimura K

    2016-06-01

    Full Text Available Katsuhiro Yoshimura,1,2 Yuzo Suzuki,1,2 Tomohiro Uto,2 Jun Sato,2 Shiro Imokawa,2 Takafumi Suda1 1Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan; 2Department of Respiratory Medicine, Iwata City Hospital, Iwata, Japan Background: Pulmonary vascular remodeling is essential for understanding the pathogenesis of chronic obstructive pulmonary disease (COPD. The total cross-sectional area (CSA of small pulmonary vessels has been reported to correlate with the pulmonary artery pressure, and this technique has enabled the assessment of pulmonary vascular involvements. We investigated the contribution of morphological alterations in the pulmonary vessels to severe acute exacerbation of COPD (AE-COPD.Methods: This study enrolled 81 patients with COPD and 28 non-COPD subjects as control and assessed the percentage of CSA (%CSA less than 5 mm2 (%CSA<5 and %CSA in the range of 5–10 mm2 (%CSA5–10 on high-resolution computed tomography images.Results: Compared with the non-COPD subjects, the COPD patients had lower %CSA<5. %CSA<5 was positively correlated with airflow limitation and negatively correlated with the extent of emphysema. COPD patients with lower %CSA<5 showed significantly increased incidences of severe AE-COPD (Gray’s test; P=0.011. Furthermore, lower %CSA<5 was significantly associated with severe AE-COPD (hazard ratio, 2.668; 95% confidence interval, 1.225–5.636; P=0.010.Conclusion: %CSA<5 was associated with an increased risk of severe AE-COPD. The distal pruning of the small pulmonary vessels is a part of the risk associated with AE-COPD, and %CSA<5 might be a surrogate marker for predicting AE-COPD. Keywords: chronic obstructive pulmonary disease (COPD, acute exacerbation, pulmonary vessels, cross-sectional area (CSA, computed tomography

  11. Peristaltic Pumping of Blood Through Small Vessels of Varying Cross-Section

    Science.gov (United States)

    Misra, J. C.; Maiti, S.

    2012-11-01

    The paper is devoted to a study of the peristaltic motion of blood in the micro-circulatory system. The vessel is considered to be of varying cross-section. The progressive peristaltic waves are taken to be of sinusoidal nature. Blood is considered to be a Herschel-Bulkley fluid. Of particular concern here is to investigate the effects of amplitude ratio, mean pressure gradient, yield stress and the power law index on the velocity distribution, streamline pattern and wall shear stress. On the basis of the derived analytical expression, extensive numerical calculations have been made. The study reveals that velocity of blood and wall shear stress are appreciably affected due to the non-uniform geometry of blood vessels. They are also highly sensitive to the magnitude of the amplitude ratio and the value of the fluid index.

  12. Clinical Observation on Effect of Clearing the Governor Vessel and Refreshing the Mind Needling on Head SPECT and CT Scanning of Kids with Cerebral Palsy

    Institute of Scientific and Technical Information of China (English)

    刘振寰; 祁岩超; 潘佩光; 马美美; 钱旭光; 符文杰; 张宏雁

    2007-01-01

    目的:探讨针灸在脑瘫康复中的脑功能代偿作用.方法:100例脑瘫患儿随机分为治疗组(50例)和对照组(50例),治疗组采用通督补肾组穴:督脉穴13针配伍涌泉、阳陵泉、足三里、三阴交.和醒神头针(神庭透百会,百会透脑户和四神聪).配合康复训练.对照组单纯用康复训练.观察两组临床疗效以及头颅CT、SPECT病变恢复情况.结果:治疗组总有效率为84%,显著高于对照组总有效率的52%.治疗后发育商(DQ)治疗显著组高于对照组(P<0.01).头颅CT脑发育不良,脑萎缩的好转率和头颅SPECT脑神经元代谢功能恢复正常率,治疗组高于对照组(P<0.01)结论:针灸能促进脑功能的代偿作用.%To investigate the brain functional compensation of acupuncture in cerebral palsy rehabilitation. Method: All 100 cerebral palsy kids were randomized into a treatment group (50 cases) and a control group (50 cases). For cases in the treatment group,points of connecting the Governor Vessels and tonifying the kidney were selected: 13 points of the Governor Vessel, Yongquan (Kid 1), Yanglingquan (GB 34), Zusanli (ST 36) and Sanyinjiao (SP 6), and points of refreshing the mind were also selected: puncturing Shenting (GV 24) toward Baihui (GV 20) and puncturing Baihui (GV 20) toward Naohu (GV 17) and Sishencong (Ex-HN 1). In addition, rehabilitation training was also combined. For cases in the control group,rehabilitation training alone was adopted. Then the clinical effect and improvement through head CT scanning and SPECT were observed. Result: The total effective rate of the treatment group was 84%, significantly higher than 52% of the control group. After treatment, the DQ in the treatment group was significantly higher than the control group (P<0.01). Also, the improvement rate of brain maldevelopment and brain atrophy showed by CT scan and restoration rate of brain neuron metabolic function in the treatment group were higher than the control group

  13. Development of in-vessel type control rod drive mechanism for a innovative small reactor (Contract research)

    Energy Technology Data Exchange (ETDEWEB)

    Yoritsune, Tsutomu; Ishida, Toshihisa [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    Although the control rod drive mechanism of an existing large scale light water reactor is generally installed outside the reactor vessel, an in-vessel type control rod drive mechanism (INV-CRDM) is installed inside the reactor vessel. The INV-CRDM contributes to compactness and simplicity of the reactor system, and it can eliminate the possibility of a rod ejection accident. Therefore, INV-CRDM is an important technology adopted in an innovative small reactor. Japan Atomic Energy Research Institute (JAERI) has developed this type of CRDM driven by an electric motor, which can work under high temperature and high pressure water for the advanced marine reactor. On the basis of this research result, a driving motor coil and a bearing were developed to be used under the high temperature steam, severe condition for an innovative small reactor. About the driving motor, we manufactured the driving motor available for high temperature steam and carried out performance test under room temperature atmosphere to confirm the electric characteristic and coolability of the driving coil. With these test results and the past test results under high temperature water, we analyzed and evaluated the electric performance and coolability of the driving coil under high temperature steam. Concerning bearing, we manufactured the test pieces using some candidate material for material characteristic test and carried out the rolling wear test under high temperature steam to select the material. Consequently, we confirmed that performance of the driving coil for the advanced type driving motor, is enough to be used under high temperature steam. And, we evaluated the performance of the bearing and selected the material of the bearing, which can be used under high temperature steam. From these results, we have obtained the prospect that the INV-CRDM can be used for an innovative small reactor under steam atmosphere could be developed. (author)

  14. Acute hypertensive encephalopathy with widespread small-vessel disease at MRI in a diabetic patient: pathogenetic hypotheses

    Energy Technology Data Exchange (ETDEWEB)

    Cotton, F. [Centre Hospitalier Lyon Sud, Department of Radiology, Pierre Benite (France); Universite Claude-Bernard Lyon-I, CREATIS, UMR CNRS (France); Universite Claude-Bernard Lyon-I, Laboratoire d' Anatomie, Laennec (France); Kamoun, S.; Rety-Jacob, F.; Tran-Minh, V.A. [Centre Hospitalier Lyon Sud, Department of Radiology, Pierre Benite (France); Nighoghossian, N. [Hopital Neurologique et Neurochirurgical, Department of Neurology, Bron (France); Universite Claude-Bernard Lyon-I, CREATIS, UMR CNRS (France); Hermier, M. [Hopital Neurologique et Neurochirurgical, Department of Neuroradiology and MRI, Bron (France); Universite Claude-Bernard Lyon-I, CREATIS, UMR CNRS (France)

    2005-08-01

    We report unusual magnetic resonance imaging (MRI) findings in a diabetic patient with neglected hypertension and hyperglycemia, presenting with seizures and coma. Outcome was fatal despite intensive care. The MRI findings included bilateral insular and temporo-occipital grey and white matter involvement, and numerous, scattered, lacunar-like lesions involving the peripheral and deep white matter, basal ganglia grey matter, and brainstem. Lesions had a low apparent diffusion coefficient, and some enhanced following contrast injection. Hypertensive encephalopathy with widespread and severe acute small-vessel disease was considered. Pathophysiology is discussed. (orig.)

  15. Nuclear reactor plant accommodated in a steel pressure vessel in a small gas-cooled HT reactor

    International Nuclear Information System (INIS)

    The small HT reactor is accommodated in a steel pressure vessel together with the heat system consisting of a steam raising unit, tubular furnace and He/He heat exchanger. The operating devices are separated from the safety-related devices for removing post-shutdown heat. The post-shutdown heat removal system is situated in the primary circuit for this purpose, and is constantly in hot-standby operation. The safety of the plant is increased by shut-off devices between the steam-raising unit and the post-shutdown heat removal system. (DG)

  16. Acute hypertensive encephalopathy with widespread small-vessel disease at MRI in a diabetic patient: pathogenetic hypotheses

    International Nuclear Information System (INIS)

    We report unusual magnetic resonance imaging (MRI) findings in a diabetic patient with neglected hypertension and hyperglycemia, presenting with seizures and coma. Outcome was fatal despite intensive care. The MRI findings included bilateral insular and temporo-occipital grey and white matter involvement, and numerous, scattered, lacunar-like lesions involving the peripheral and deep white matter, basal ganglia grey matter, and brainstem. Lesions had a low apparent diffusion coefficient, and some enhanced following contrast injection. Hypertensive encephalopathy with widespread and severe acute small-vessel disease was considered. Pathophysiology is discussed. (orig.)

  17. Bleeding risk during latent period after gamma knife surgery for small cerebral arteriovenous malformation. Comparison with natural history

    International Nuclear Information System (INIS)

    We studied the bleeding risk during latency period after gamma knife surgery (GKS) for small (3 cm or less) cerebral arteriovenous malformations (AVMs). We analyzed 720 cases with a natural history and 100 cases with GKS. The incidence of bleeding was calculated from the data of the former cases according to the history of bleeding and their age and was compared with the actual number obtained from the latter. The estimated incidence of bleeding was 1.6 for unruptured AVMs and 5.5 for ruptured AVMs, whereas the actual incidence of bleeding was 2 for unruptured and 0 for ruptured. The difference was statistically significant in the ruptured but was not significant in the unruptured. These results lead us to conclude that the bleeding risk during latency period after GKS for small AVMs is almost the same in the unruptured, but is decreased in the ruptured. (author)

  18. Application of small specimens to fracture mechanics characterization of irradiated pressure vessel steels

    International Nuclear Information System (INIS)

    In this study, precracked Charpy V-notch (PCVN) specimens were used to characterize the fracture toughness of unirradiated and irradiated reactor pressure vessel steels in the transition region by means of three-point static bending. Fracture toughness at cleavage instability was calculated in terms of elastic-plastic KJc values. A statistical size correction based upon weakest-link theory was performed. The concept of a master curve was applied to analyze fracture toughness properties. Initially, size-corrected PCVN data from A 533 grade B steel, designated HSST Plate O2, were used to position the master curve and a 5% tolerance bound for KJc data. By converting PCVN data to IT compact specimen equivalent KJc data, the same master curve and 5% tolerance bound curve were plotted against the Electric Power Research Institute valid linear-elastic KJc database and the ASME lower bound KIc curve. Comparison shows that the master curve positioned by testing several PCVN specimens describes very well the massive fracture toughness database of large specimens. These results give strong support to the validity of KJc with respect to KIc in general and to the applicability of PCVN specimens to measure fracture toughness of reactor vessel steels in particular. Finally, irradiated PCVN specimens of other materials were tested, and the results are compared to compact specimen data. The current results show that PCVNs demonstrate very good capacity for fracture toughness characterization of reactor pressure vessel steels. It provides an opportunity for direct measurement of fracture toughness of irradiated materials by means of precracking and testing Charpy specimens from surveillance capsules. However, size limits based on constraint theory restrict the operational test temperature range for KJc data from PCVN specimens. 13 refs., 8 figs., 1 tab

  19. [The concept of cerebral lacunae from 1838 to the present].

    Science.gov (United States)

    Poirier, J; Derouesné, C

    1985-01-01

    The term lacunae was first used by Dechambre (1838) referring to small cavities developed during the process of resorption within cerebral softenings. Some years later, lacunae was applied by Durand-Fardel (1843) to small cavities located in the basal ganglia and hypothetically attributed to old, healed cerebral softenings. Durand-Fardel (1842, 1854) described "l'état criblé" as many round small holes ("criblures") always containing a patient blood vessel and located in the hemispheric white matter. He believed that "état criblé" was caused by mechanical compression of cerebral tissue related to the dilatation of the blood cerebral vessels during repetitive cerebral congestion. Chronic dementia or delirium were considered as the clinical counterpart of "état criblé". In the second half of the XIXth century, the few reports about lacunae were confusing due to the imprecise use of the terms "lacunae" and "état criblé". Furthermore, some authors described lacunae as sequelae of haemorrhage, others as old softenings or both. In the beginning of the XXth century, the masterly work of P. Marie (1901) established a clear distinction between the "foyers lacunaires de désintégration" and "état criblé" de Durand-Fardel or single perivascular dilatation of one of the lenticulo-striate arteries at its entrance into the lenticular nucleus or post-mortem charges (cerebral porosity, "état de fromage de gruyère"). He described lacunae as small cerebral softenings caused by occlusion of the blood vessels by a "local arteriosclerotic process". However, he also stated that some lacunae containing a patent blood vessel were due to a perivascular space dilatation destroying the adjacent brain parenchyma by a process of "destructive vaginalitis". Marie observed that lacunae were frequently clinically asymptomatic, but "that the hemiplegia of the old people was more often due to cerebral lacunae than to cerebral haemorrhage or softening". During the first half of the XXth

  20. Effects of JPEG data compression on magnetic resonance imaging evaluation of small vessels ischemic lesions of the brain

    International Nuclear Information System (INIS)

    Objective: to establish the maximum achievable JPEG compression ratio without affecting quantitative and qualitative magnetic resonance imaging analysis of ischemic lesion in small vessels of the brain. Material and method: fifteen DICOM images were converted to JPEG with a compression ratio of 1:10 to 1:60 and were assessed together with the original images by three neuro radiologists. The number, morphology and signal intensity of the lesions were analyzed. Results: lesions were properly identified up to a 1:30 ratio. More lesions were identified with a 1:10 ratio then in the original images. Morphology and edges were properly evaluated up toa 1:40 ratio. Compression did not affect signal. Conclusion: small lesions were identified ( < 2 mm ) and in all compression ratios the JPEG algorithm generated image noise that misled observers to identify more lesions in JPEG images then in DICOM images, thus generating false-positive results.(author)

  1. The value of performing head CT in screening for cerebral metastases in patients with potentially resectable non-small cell lung cancer: experience from a UK cardiothoracic centre

    International Nuclear Information System (INIS)

    AIM: To evaluate the whether screening for cerebral metastases in neurologically intact patients with potentially resectable non-small cell lung cancer patients is both worthwhile and cost-effective. METHODS: We prospectively performed computed tomography (CT) of the head in 105 consecutive patients with potentially resectable lung cancer over an 18-month period. None of these patients had neurological symptoms or signs. RESULTS: Five patients (4.8%) with cerebral metastases were identified using CT. At our institution the financial saving of avoiding five thoracotomies was 45,000 Pounds, whilst the cost of performing 105 head CTs was 16,000 Pounds. This represented a substantial saving for the healthcare provider and preserved the quality of life in five patients. CONCLUSIONS: We conclude that screening for cerebral metastases in neurologically intact patients with potentially resectable non small cell lung cancer patients is both worthwhile and cost effective

  2. Cerebral amyloid angiopathy severity is linked to dilation of juxtacortical perivascular spaces.

    Science.gov (United States)

    van Veluw, Susanne J; Biessels, Geert Jan; Bouvy, Willem H; Spliet, Wim Gm; Zwanenburg, Jaco Jm; Luijten, Peter R; Macklin, Eric A; Rozemuller, Annemieke Jm; Gurol, M Edip; Greenberg, Steven M; Viswanathan, Anand; Martinez-Ramirez, Sergi

    2016-03-01

    Perivascular spaces are an emerging marker of small vessel disease. Perivascular spaces in the centrum semiovale have been associated with cerebral amyloid angiopathy. However, a direct topographical relationship between dilated perivascular spaces and cerebral amyloid angiopathy severity has not been established. We examined this association using post-mortem magnetic resonance imaging in five cases with evidence of cerebral amyloid angiopathy pathology. Juxtacortical perivascular spaces dilation was evaluated on T2 images and related to cerebral amyloid angiopathy severity in overlying cortical areas on 34 tissue sections stained for Amyloid β. Degree of perivascular spaces dilation was significantly associated with cerebral amyloid angiopathy severity (odds ratio = 3.3, 95% confidence interval 1.3-7.9, p = 0.011). Thus, dilated juxtacortical perivascular spaces are a promising neuroimaging marker of cerebral amyloid angiopathy severity. PMID:26661250

  3. Effects of a protein glycocalyx in the hemodynamics of small blood vessels

    Science.gov (United States)

    Dimakopoulos, Yiannis; Delidakis, George; Tsamopoulos, John

    2015-11-01

    Glycocalyx is a protein layer of approximate thickness 0.5 μm that lines vessel walls. We study the effects this layer has on the blood flow inside arterioles and venules, where the relative size of the glycocalyx is significant. To properly describe phenomena that naturally occur in blood flow, such as the inhomogeneous distribution of red blood cells and their aggregation, we use an improved viscoelastic constitutive model. The glycocalyx layer is modeled as fixed porous media. Cells cannot penetrate inside it, since its hydraulic permeability is very low, and the flow inside this layer is described by the equations for a viscous fluid with an extra Brinkman term to account for the effects the porous medium has on the flow. The closed set of equations is solved using the Finite Element method, assuming steady-state with dependence only in the r-direction. Our results are favorably compared with the in vivo velocity profiles in venules of mice produced by Damiano et al. (2004) and the formation of cell-free layer near glycocalyx. Flow inside the glycocalyx layer is found to be severely attenuated due to the low hydraulic permeability, which can have interesting implications in the transport of various substances form the blood to the tissues or in the use of shear stresses as signals for the endothelial surface cells. Finally, we simulate the transient blood flow under pulsatile conditions.

  4. Automatic anatomical labeling of the complete cerebral vasculature in mouse models.

    Science.gov (United States)

    Ghanavati, Sahar; Lerch, Jason P; Sled, John G

    2014-07-15

    Study of cerebral vascular structure broadens our understanding of underlying variations, such as pathologies that can lead to cerebrovascular disorders. The development of high resolution 3D imaging modalities has provided us with the raw material to study the blood vessels in small animals such as mice. However, the high complexity and 3D nature of the cerebral vasculature make comparison and analysis of the vessels difficult, time-consuming and laborious. Here we present a framework for automated segmentation and recognition of the cerebral vessels in high resolution 3D images that addresses this need. The vasculature is segmented by following vessel center lines starting from automatically generated seeds and the vascular structure is represented as a graph. Each vessel segment is represented as an edge in the graph and has local features such as length, diameter, and direction, and relational features representing the connectivity of the vessel segments. Using these features, each edge in the graph is automatically labeled with its anatomical name using a stochastic relaxation algorithm. We have validated our method on micro-CT images of C57Bl/6J mice. A leave-one-out test performed on the labeled data set demonstrated the recognition rate for all vessels including major named vessels and their minor branches to be >75%. This automatic segmentation and recognition methods facilitate the comparison of blood vessels in large populations of subjects and allow us to study cerebrovascular variations. PMID:24680868

  5. Cerebral Arteriosclerosis

    Science.gov (United States)

    ... the brain can cause a hemorrhagic stroke. Both types of stroke can be fatal. Cerebral arteriosclerosis is also related to a condition known as vascular dementia, in which small, symptom-free strokes cause cumulative damage and death to neurons (nerve cells) in the brain. Personality changes in ...

  6. Analysis of microstructural changes in irradiated pressure vessel steels using small angle neutron scattering

    International Nuclear Information System (INIS)

    Small Angle Neutron Scattering (SANS) has been used to investigate the influence of Cu, Ni and P on radiation hardening and embrittlement in neutron irradiated ferritic steels. Micro-structural features 23 n m-2 (E>1MeV) and temperatures 1800C-2900C. The analysis suggests two hardening components, one independent of Cu content and one dependent on Cu content >approx. 0.1 wt %. The results are discussed in terms of the precipitation of copper or copper-rich particles containing Fe, Ni or vacancies. (UK)

  7. Small scale module of the rat granular retrosplenial cortex: an example of minicolumn-like structure of the cerebral cortex

    Directory of Open Access Journals (Sweden)

    Noritaka eIchinohe

    2012-01-01

    Full Text Available Structures associated with the small scale module called minicolumn can be observed frequently in the cerebral cortex. However, the description of functional characteristics remains obscure. A significant confounding factor is the marked variability both in the definition of a minicolumn and in the diagnostic markers for identifying a minicolumn (see for review, Jones, 2000, DeFelipe et al., 2003; Rockland and Ichinohe, 2004. Within a minicolumn, cell columns are easily visualized by conventional Nissl staining. Dendritic bundles were first discovered with Golgi methods, but are more easily seen with MAP2-immunohistochemisty. Myelinated axon bundles can be seen by Tau-immunohistochemistry or myelin staining. Axon bundles of double bouquet cell can be seen by calbindin-immunohistochemistry. The spatial interrelationship among these morphological elements is more complex than expected and is neither clear nor unanimously agreed upon. In this review, I would like to focus first on the minicolumnar structure found in layers 1 and 2 of the rat granular retrosplenial cortex (GRS. This modular structure was first discovered as a combination of prominent apical dendritic bundles from layer 2 pyramidal neurons and spatially-matched thalamocortical patchy inputs (Wyss et al., 2000. Further examination showed more intricate components of this modular structure, which will be reviewed in this paper. Second, the postnatal development of this structure and potential molecular players for its formation will be reviewed. Thirdly, I will discuss how this modular organization is transformed in mutant rodents with a disorganized layer structure in the cerebral cortex (i.e., reeler mouse and Shaking Rat Kawasaki. Lastly, the potential significance of this type of module will be discussed.

  8. Evaluation of fracture toughness and tensile properties of reactor pressure vessel steel by small punch test and automated ball indentation technique

    International Nuclear Information System (INIS)

    Miniature sample testing techniques like Small Punch Test (SPT) and Automated Ball Indentation (ABI) test are being developed to evaluate mechanical property and fracture toughness of reactor materials. Small size specimens provide the advantage of testing highly radioactive samples with a low manrem exposure. SPTand ABI tests were carried out on the prepared samples from Advance Reactor Pressure Vessel Steel (ARPV) materials to evaluate the UTS, YS, fracture toughness values. The paper presents the comparative results of studies carried out, on A533B steel and Advanced Reactor Pressure Vessel (ARPV) steel. (author)

  9. Proton density differences in signal characteristics of multiple sclerosis plaques versus white matter lesions of small vessel disease and vasculitis on high-field strength MR images

    International Nuclear Information System (INIS)

    This paper determines if variations in signal intensity characteristics on multi-spin-echo images obtained with a high-field-strength magnet can be useful in differentiating demyelinating plaques of multiple sclerosis from other pathologic white matter processes due to small vessel disease and vasculities. Using the first of two multi-spin-echo images obtained with a General Electric 1.5-T magnet, the investigators compared signal intensity characteristics in 30 patients with a firm clinical diagnosis of multiple sclerosis versus a control group of 30 patients with a known clinical history of small-vessel disease and vasculitis are isodense to gray matter on proton-density images

  10. Small angle neutron scattering study of radiation damage in reactor vessel materials

    Energy Technology Data Exchange (ETDEWEB)

    Retfalvi, E.; Toeroek, G.; Rosta, L. [Research Institute for Solid State Physics and Optics, Budapest (Hungary); Retfalvi, E. [Institute of Nuclear Techniques, Budapest (Hungary)

    2001-07-01

    The walls of a reactor tank in an operating nuclear power plant are exposed to high intensity gamma and neutron radiation. The effect of gamma radiation on mechanical properties is much less than that of neutrons, and this gamma radiation can even be favorable, for example the effect of gamma heating, might assists in the recombination of defects. The neutron radiation gives the main contribution due to impairment mainly by fast neutrons. The interaction of neutrons with materials has two mechanisms, one is the transmutation and the second mechanism is the scattering of neutrons on the atoms of the crystal lattice. In the process of transmutation new elements are created, mainly with formation of noble gases. This is a damaging procedure, because in this way bubbles are formed at the boundaries of crystallites. In the second process analyzing the path of a neutron in the crystal lattice we can distinguish two sections: in the first period the neutron with high energy knocks out atoms from the lattice. These atoms start a scattering cascade and at the end they may stop in interstitial positions. So in this period the surrounding of the path of the neutron contains a lot of vacancies and interstitial atoms. In the second period the neutron is quite slow so the neutron loses its energy in a shorter distance: here the metal can locally melt or a phase transition can take place. These are the precipitates which we can observe with the small angle neutron scattering technique, as well as the gaseous bubbles, if the volume fraction of these objects match the measurable scale. (author)

  11. Thrombotic thrombocytopenic purpura: MRI demonstration of persistent small cerebral infarcts after clinical recovery

    International Nuclear Information System (INIS)

    Abnormalities in the brain of patients with thrombotic thrombocytopenic purpura (TTP) are infrequent on MRI, often reversible and mainly limited to symptomatic stages of the disease. We report a case in which high-resolution MRI demonstrated multiple persistent small cortical infarcts after clinical remission. High-resolution MRI investigations may detect clinically latent but permanent brain damage, and complement clinical judgement in guiding therapeutic decisions. (orig.)

  12. Thermal-hydraulic Analysis and Code Assessment for Reactor Vessel Upper-head Small Break LOCA using SPACE code

    International Nuclear Information System (INIS)

    In 2002, the discovery of thinning of the vessel head wall at the Davis Besse nuclear power plant reactor indicated the possibility of an SBLOCA in the upper-head as a result of circumferential cracking of a Control Red Drive Mechanism (CRDM) penetration nozzle. Several experimental tests have been performed at the large scale test facility to simulate the behavior of a PWR during an upper-head SBLOCA. Organization for Economic Co-operation and Development Nuclear Energy Agency Rig of Safety Assessment (OECD/NEA ROSA) Test 6.1 was performed with a break size equivalent to 1.9% cold leg break. Additionally, analysis of an upper-head SBLOCA with high pressure safety injection failed in a Westinghouse PWR was examined taking into account different accident management actions and conditions in order to check the suitability. In this study, the thermal-hydraulic analysis was performed for postulated upper-head breaks in OPR 1000 (Optimized Power Reactor 1000 MWe) using SPACE (Safety and Performance Analysis Code for Nuclear Power Plants) code, which has been developed in recent years by the Korea Hydro and Nuclear Power Company (KHNP). The calculation results were compared with MARS-KS code to assess the capability of the SPACE code to simulate the transient thermal-hydraulic behavior. Inspections of existing nuclear power plants have pointed out the possibility of small break loss of coolant accidents (SBLOCAs) were initiated by a small break located in the upper-head of the reactor pressure vessel. The thermal-hydraulic analysis was performed for postulated upper-head breaks in OPR 1000 plant using SPACE (Safety and Performance Analysis Code for Nuclear Power Plants) code, which has been developed in recent years by the Korea Hydro and Nuclear Power Company (KHNP). The calculation results were compared with MARS-KS code to assess the capability of the SPACE code to simulate the transient thermal-hydraulic behavior. The prediction showed good agreement with the MARS

  13. Thermal-hydraulic Analysis and Code Assessment for Reactor Vessel Upper-head Small Break LOCA using SPACE code

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Minhee; Kim, Seyun [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    In 2002, the discovery of thinning of the vessel head wall at the Davis Besse nuclear power plant reactor indicated the possibility of an SBLOCA in the upper-head as a result of circumferential cracking of a Control Red Drive Mechanism (CRDM) penetration nozzle. Several experimental tests have been performed at the large scale test facility to simulate the behavior of a PWR during an upper-head SBLOCA. Organization for Economic Co-operation and Development Nuclear Energy Agency Rig of Safety Assessment (OECD/NEA ROSA) Test 6.1 was performed with a break size equivalent to 1.9% cold leg break. Additionally, analysis of an upper-head SBLOCA with high pressure safety injection failed in a Westinghouse PWR was examined taking into account different accident management actions and conditions in order to check the suitability. In this study, the thermal-hydraulic analysis was performed for postulated upper-head breaks in OPR 1000 (Optimized Power Reactor 1000 MWe) using SPACE (Safety and Performance Analysis Code for Nuclear Power Plants) code, which has been developed in recent years by the Korea Hydro and Nuclear Power Company (KHNP). The calculation results were compared with MARS-KS code to assess the capability of the SPACE code to simulate the transient thermal-hydraulic behavior. Inspections of existing nuclear power plants have pointed out the possibility of small break loss of coolant accidents (SBLOCAs) were initiated by a small break located in the upper-head of the reactor pressure vessel. The thermal-hydraulic analysis was performed for postulated upper-head breaks in OPR 1000 plant using SPACE (Safety and Performance Analysis Code for Nuclear Power Plants) code, which has been developed in recent years by the Korea Hydro and Nuclear Power Company (KHNP). The calculation results were compared with MARS-KS code to assess the capability of the SPACE code to simulate the transient thermal-hydraulic behavior. The prediction showed good agreement with the MARS

  14. Characterization of histamine receptors in isolated human cerebral arteries.

    OpenAIRE

    Ottosson, A; Jansen, I.; Edvinsson, L.

    1988-01-01

    1. The subtypes of histamine-receptors which mediate dilatation of small human cerebral arteries have been characterized in vitro using 'selective' agonists and antagonists. 2. Dilator responses were studied after preconstriction with prostaglandin F2 alpha, since contraction was not seen with histamine concentrations up to 10(-4) M. Histamine caused a concentration-related relaxation of cerebral vessels with an IC50 value of 5.2 +/- 1.6 x 10(-8) M. 3. Mepyramine caused a parallel shift to th...

  15. "Student Lab"-on-a-Chip: Integrating Low-Cost Microfluidics into Undergraduate Teaching Labs to Study Multiphase Flow Phenomena in Small Vessels

    Science.gov (United States)

    Young, Edmond W. K.; Simmons, Craig A.

    2009-01-01

    We describe a simple, low-cost laboratory session to demonstrate the Fahraeus-Lindqvist effect, a microphase flow phenomenon that occurs in small blood vessels and alters the effective rheological properties of blood. The experiments are performed by flowing cells through microchannels fabricated by soft lithography and characterization of cell…

  16. Potassium channelopathy-like defect underlies early-stage cerebrovascular dysfunction in a genetic model of small vessel disease

    DEFF Research Database (Denmark)

    Dabertrand, Fabrice; Krøigaard, Christel; Bonev, Adrian D; Cognat, Emmanuel; Dalsgaard, Thomas; Domenga-Denier, Valérie; Hill-Eubanks, David C; Brayden, Joseph E; Joutel, Anne; Nelson, Mark T

    2015-01-01

    ) mice, a genetic model of CADASIL, revealed functional defects in cerebral (pial) arteries on the surface of the brain at an early stage of disease progression. Here, using parenchymal arterioles (PAs) from within the brain, we determined the molecular mechanism underlying the early functional deficits...

  17. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization

    OpenAIRE

    Birgit Huber; Sascha Engelhardt; Wolfdietrich Meyer; Hartmut Krüger; Annika Wenz; Veronika Schönhaar; Tovar, Günter E. M.; Kluger, Petra J.; Kirsten Borchers

    2016-01-01

    Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA) for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of appr...

  18. Intra-arterial thrombolysis using rt-PA in patients with acute stroke due to vessel occlusion of anterior and/or posterior cerebral circulation

    International Nuclear Information System (INIS)

    The aim of our study was to evaluate the safety and efficacy of intra-arterial (IA) thrombolysis using recombinant tissue plasminogen activator (rt-PA) in patients with acute stroke due to occlusion in the anterior or posterior circulation. We retrospectively analyzed the clinical and radiological data of 88 consecutive patients with acute ischemic stroke who underwent emergency cerebral angiography for the purpose of subsequent IA thrombolysis. The neurological deficit on admission and discharge was graded using the National Institutes of Health Stroke Scale (NIHSS) score. Baseline computer tomography (CT) scans were examined for any signs indicative of cerebral ischemia. The angiographic findings were classified according to the Thrombolysis in Myocardial Infarction (TIMI) score for myocardial infarction. Follow-up CT scans were examined for hemorrhagic complication. Of the 88 patients who underwent IA thrombolysis, 63 presented with complete or partial arterial occlusion in the suspected perfusion area. In these 63 patients, the median NIHSS score dropped from 15 points on admission to 10 points at discharge. The recanalization rate was 52.6% for partial and complete reperfusion. In-hospital mortality was 20.6% (9.1% for carotid, 44.4% for basilar territory occlusion). Intracerebral bleeding (ICB) occurred in 38.6% of the patients with occlusion in the anterior circulation, resulting in these patients presenting a worse clinical outcome than those without ICB. Only minor extracranial bleedings occurred in 20.6% of patients. Patients with ICB had a significantly higher frequency of ischemic signs on the baseline CT scan. Occlusion of a cerebral artery is present in about 75% of the patients eligible for thrombolytic therapy. Intra-arterial thrombolysis using rt-PA in patients with acute ischemic stroke can achieve re-vascularization, although ICB remains the major risk factor affecting its efficacy. (orig.)

  19. Intra-arterial thrombolysis using rt-PA in patients with acute stroke due to vessel occlusion of anterior and/or posterior cerebral circulation

    Energy Technology Data Exchange (ETDEWEB)

    Tountopoulou, Argyro; Ahl, Bjoern; Weissenborn, Karin [Hannover Medical School, Department of Neurology and Clinical Neurophysiology, Hannover (Germany); Becker, Hartmut; Goetz, Friedrich [Hannover Medical School, Department of Neuroradiology, Hannover (Germany)

    2008-01-15

    The aim of our study was to evaluate the safety and efficacy of intra-arterial (IA) thrombolysis using recombinant tissue plasminogen activator (rt-PA) in patients with acute stroke due to occlusion in the anterior or posterior circulation. We retrospectively analyzed the clinical and radiological data of 88 consecutive patients with acute ischemic stroke who underwent emergency cerebral angiography for the purpose of subsequent IA thrombolysis. The neurological deficit on admission and discharge was graded using the National Institutes of Health Stroke Scale (NIHSS) score. Baseline computer tomography (CT) scans were examined for any signs indicative of cerebral ischemia. The angiographic findings were classified according to the Thrombolysis in Myocardial Infarction (TIMI) score for myocardial infarction. Follow-up CT scans were examined for hemorrhagic complication. Of the 88 patients who underwent IA thrombolysis, 63 presented with complete or partial arterial occlusion in the suspected perfusion area. In these 63 patients, the median NIHSS score dropped from 15 points on admission to 10 points at discharge. The recanalization rate was 52.6% for partial and complete reperfusion. In-hospital mortality was 20.6% (9.1% for carotid, 44.4% for basilar territory occlusion). Intracerebral bleeding (ICB) occurred in 38.6% of the patients with occlusion in the anterior circulation, resulting in these patients presenting a worse clinical outcome than those without ICB. Only minor extracranial bleedings occurred in 20.6% of patients. Patients with ICB had a significantly higher frequency of ischemic signs on the baseline CT scan. Occlusion of a cerebral artery is present in about 75% of the patients eligible for thrombolytic therapy. Intra-arterial thrombolysis using rt-PA in patients with acute ischemic stroke can achieve re-vascularization, although ICB remains the major risk factor affecting its efficacy. (orig.)

  20. EFFECTS OF RAPAMYCIN ON CEREBRAL OXYGEN SUPPLY AND CONSUMPTION DURING REPERFUSION AFTER CEREBRAL ISCHEMIA

    Science.gov (United States)

    CHI, O. Z.; BARSOUM, S.; VEGA-COTTO, N. M.; JACINTO, E.; LIU, X.; MELLENDER, S. J.; WEISS, H. R.

    2016-01-01

    Abstract—Activation of the mammalian target of rapamycin (mTOR) leads to cell growth and survival. We tested the hypothesis that inhibition of mTOR would increase infarct size and decrease microregional O2 supply/consumption balance after cerebral ischemia–reperfusion. This was tested in isoflurane-anesthetized rats with middle cerebral artery blockade for 1 h and reperfusion for 2 h with and without rapamycin (20 mg/kg once daily for two days prior to ischemia). Regional cerebral blood flow was determined using a C14-iodoantipyrine autoradiographic technique. Regional small-vessel arterial and venous oxygen saturations were determined microspectrophotometrically. The control ischemic-reperfused cortex had a similar blood flow and O2 consumption to the contralateral cortex. However, microregional O2 supply/consumption balance was significantly reduced in the ischemic-reperfused cortex. Rapamycin significantly increased cerebral O2 consumption and further reduced O2 supply/consumption balance in the reperfused area. This was associated with an increased cortical infarct size (13.5 ± 0.8% control vs. 21.5 ± 0.9% rapamycin). We also found that ischemia–reperfusion increased AKT and S6K1 phosphorylation, while rapamycin decreased this phosphorylation in both the control and ischemic-reperfused cortex. This suggests that mTOR is important for not only cell survival, but also for the control of oxygen balance after cerebral ischemia–reperfusion. PMID:26742793

  1. Three-Dimensional Time-of-Flight Magnetic Resonance Angiography of Intracranial Vessels in a Canine Model of Ischemic Stroke with Permanent Occlusion of the Middle Cerebral Artery

    OpenAIRE

    KANG, Byeong-Teck; Jang, Dong-Pyo; Gu, Su-Hyun; Kim, Young-Bo; Lim, Chae-Young; Lee, Jong-Hwan; Woo, Eung-Je; Cho, Zang-Hee; Park, Hee-Myung

    2009-01-01

    The purpose of this study was to evaluate the potential efficacy of 3-dimensional time-of-flight magnetic resonance angiography (TOF-MRA) to validate a canine ischemic stroke model. Ischemic stroke was induced through permanent middle cerebral artery occlusion (MCAO) in 5 healthy Beagle dogs. T2-turbo spin echo images and TOF-MRA were obtained with a 1.5-T magnetic resonance system before and 3 and 10 d after MCAO. In 3 dogs, angiograms of the brain obtained at 3 d after MCAO showed complete ...

  2. Cerebral angiography in patients with complicated migraine

    International Nuclear Information System (INIS)

    38 patients (mean age: 29 years) were investigated by means of complete 4-vessel angiography: all of them were suffering from complicated migraine without detectable vascular malformation. Stenoses of the great craniocervical vessels were found in 11 patients (28.9%), but there was not a single case of vascular occlusion. A correlation between the localization of the stenosis, the localization of the headache and the presumed region of the transient cerebral function disturbance was found only in a few patients. Concerning the morphological changes of the small intracranial arterial branches, there was hardly an difference between clinically affected and non-affected territories of the middle cerebral artery. The angiograms of the 38 cases of complicated migraine were compared with the angiograms of 40 patients suffering from strokes in the young and those of 49 patients with transient ischaemic attacks. There were remarkably fewer stenoses or occlusions in the great craniocervical arteries of patients suffering from complicated migraine (28.9%) than in the vessels of cases of stroke in the young (52.5%). However, the incidence was comparable with the results in patients with transient ischaemic attacks (34.7%). The degree of morphological changes in the small intracranial arterial branches is likely to depend primarily on the patient's age and less on the diagnosis. The results suggest that in almost 30% of patients with complicated migraine - even at juvenile age-stenoses of the great craniocervical vessels might be found. However, considering the fact that most of the stenoses are without haemodynamic significance and their localization is not in agreement with the clinical data, the pathogenetic value of these vessel wall changes is highly questionable. (Author)

  3. Natriuretic peptides and cerebral hemodynamics

    DEFF Research Database (Denmark)

    Guo, Song; Barringer, Filippa; Zois, Nora Elisabeth;

    2014-01-01

    decompensated disease. In contrast, their biological effects on the cerebral hemodynamics are poorly understood. In this mini-review, we summarize the hemodynamic effects of the natriuretic peptides with a focus on the cerebral hemodynamics. In addition, we will discuss its potential implications in diseases...... where alteration of the cerebral hemodynamics plays a role such as migraine and acute brain injury including stroke. We conclude that a possible role of the peptides is feasible as evaluated from animal and in vitro studies, but more research is needed in humans to determine the precise response on...... cerebral vessels....

  4. Cerebral Hypoxia

    Science.gov (United States)

    ... Enhancing Diversity Find People About NINDS NINDS Cerebral Hypoxia Information Page Synonym(s): Hypoxia, Anoxia Table of Contents ( ... Trials Organizations Publicaciones en Español What is Cerebral Hypoxia? Cerebral hypoxia refers to a condition in which ...

  5. Cerebrovascular hemodynamics in patients with cerebral arteriosclerosis

    Institute of Scientific and Technical Information of China (English)

    Jianbo Yang; Changcong Cui; Chengbin Wu

    2011-01-01

    The present study observed hemodynamic changes in 26 patients with cerebral arteriosclerosis using a cerebral circulation dynamics detector and transcranial Doppler.In patients with cerebral arteriosclerosis the blood supply and flow rate in the bilateral carotid arteries and the blood flow rate in the anterior cerebral and middle cerebral arteries were similar to normal controls, but the cerebral vascular resistance, critical pressure and pulsatility index were increased, and cerebral arterial elasticity and cerebral blood flow autoregulation were decreased.Compared with the lesioned hemisphere of patients with cerebral infarction, the total blood supply and blood flow rate of patients with cerebral arteriosclerosis were higher.Compared with normal subjects, patients with cerebral arteriosclerosis exhibited cognitive disturbances, mainly in short-term memory, attention, abstract capability, and spatial and executive dysfunction.Results showed that cerebral arteriosclerosis does not directly affect the blood supply of a cerebral hemisphere, but affects cognitive function.The increased cerebral vascular resistance and reduced autoregulation of cerebral blood vessels may be important hemodynamic mechanisms of arteriosclerosis-induced cerebral infarction.

  6. Vessel Operating Units (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data for vessels that are greater than five net tons and have a current US Coast Guard documentation number. Beginning in1979, the NMFS...

  7. Molecular identification of Emericella echinulata as a cause of Cerebral Aspergillosis in a patient following small bowel and liver transplantation

    Science.gov (United States)

    Molecular methods are now more commonly used for identification of the aspergilli and their teleomorphs and have led to reports of species not previously recognized as causing human disease. We report the first case of cerebral aspergillosis in a compromised patient caused by Emericella echinulata,...

  8. Cerebral MRI findings in very-low-birth-weight and small-for-gestational-age children at 15 years of age

    International Nuclear Information System (INIS)

    A high prevalence of abnormal cerebral MRI findings has been reported in low-birth-weight children. To compare MRI findings in very-low-birth-weight (VLBW) and term small-for-gestational-age (SGA) children with controls in early adolescence. Cerebral MRI was used to examine 55 VLBW, 54 SGA and 66 controls at 15 years of age. The MR images were qualitatively assessed, and size of ventricles, white-matter and grey-matter abnormalities were reported. The VLBW teenagers had a higher prevalence of various MRI abnormalities than SGA children and controls. Dilation of the ventricular system, especially of the occipital horns, was found in 82% of the VLBW group, in 19% of the SGA group and in 21% of controls. White-matter reduction was found in 53% of the VLBW, in 6% of the SGA and in 2% of controls. Corpus callosum thinning was found in 47% of the VLBW, in 2% of the SGA and in 6% of controls. Periventricular gliosis was found in 29% of the VLBW, in 4% of the SGA and in 8% of controls. Cerebral MRI pathology in white matter is a common finding in VLBW teenagers. The findings may indicate minor perinatal PVL with resulting loss of white-matter tissue and ventricular dilation. (orig.)

  9. Vessel encoded arterial spin labeling with cerebral perfusion: preliminary study%血管编码动脉自旋标记MR脑灌注成像初步研究

    Institute of Scientific and Technical Information of China (English)

    吴冰; 蒋学祥; 方竞; 王晶; 郭佳; 章蓓茹; 肖江喜; 谢晟; Eric C.Wong; 张珏; 王霄英

    2008-01-01

    目的 初步应用血管编码动脉自旋标记MR脑灌注成像技术选择件标记双侧颈内动脉及后循环的血流分布区.方法 使用伪连续动脉自旋标记成像方法 对7名健康志愿者和6例脑血管病患者的左、右颈内动脉及椎基底动脉编码进行头部横断而成像和图像后处理,得到来源于上述不同血管的脑血流量(CBF)的灌注分布图,计算7名志愿者的双侧大脑厌、白质及半脑的CBF.比较脑血管病患者的血流分布结果 与DSA图像的一致性及低灌注区域与液体衰减反转恢复(FLAIR)T2WI的高信号区域大小.结果 定量测量正常志愿者的半CBF为(32.6±4.3)ml·min-1·100 g-1,脑白质血流最(10.8±0.9)ml·min-1·100 g-1,脑灰质血流量(55.6±2.9)ml·min-1·100 g-1.脑血管病患者的脑血流分布异常、侧支循环血流分布与DSA对应良好;所有患者低灌注区域比FLAIR T2WI显示的高信号区域范围更大.结论 血管编码动脉自旋标记MR脑灌注成像可以无创地定性并定量不同血管来源的脑血供.%Objective To evaluate a noninvasive vessel encoded imaging for selective mapping of the flow territories of the left and right internal carotid arteries and vertebral-basilar arteries. Methods Seven volunteers [(33.5±4.1) years ; 3 men, 4 women] and 6 patients [(55.2 ± 3.2) years; 2 men,4women] were given written informed consent approved by the institutional review board before participating in the study. A pseudo-continuous tagging pulse train is modified to encode all vessels of interest. The selectivity of this method was demonstrated. Regional perfusion imaging was developed on the same arterial spin labeling sequence. Perfusion-weighted images of the selectively labeled cerebral arteries were obtained by subtraction of the labeled from control images. The CBF values of hemisphere, white matter, and gray matter of volunteers were calculated. The vessel territories on patients were compared with DSA. The low

  10. CBF and CMRo2 during craniotomy for small supratentorial cerebral tumours in enflurane anaesthesia. A dose-response study

    International Nuclear Information System (INIS)

    In 14 patients with supratentorial cerebral tumours with midline shift ≤ 10 mm, cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRo2) were measured twice on the contralateral side of the craniotomy, using a modification of the Kety and Schmidt method. For induction of anaesthesia, thiopental, fentanyl and pancuronium were used. The anaesthesia was maintained with enflurane 1% in nitrous oxide 67%. Moderate hypocapnia to a level averaging 4.3 kPa was achieved. The patients were divided into two groups. In group 1 (n=7), 1% enflurane was used throughout the anaesthesia, and CBF and CMRo2 measured about 70 min after induction averaged 30.1 ml 100 g-1 min-1 and 1.98 ml O2 100 g-1 min-1, respectively. During the second CBF study 1 h later, CBF and CMRo2 were unchanged (P>0.05). In group 2 (n=7), the inspiratory enflurane concentration was increased from 1 to 2% after the first CBF measurement. In this group a significant decrease in CMRo2 was observed, while CBF was unchanged. In six patients EEG was recorded simultaneously with the CBF measurements. In patients subjected to increasing enflurane concentration (Group 2), a suppression in the EEG activity was observed without spike waves. It is concluded that enflurane induces a dose-related decrease in CMRo2 and suppression in the EEG activity, whereas CBF was unchanged (author)

  11. An investigation of cerebral magnetic resonance angiography (MRA), part 9. Diagnostic ability of intracranial occlusive vessels with MRA using 1.5 T MRI

    International Nuclear Information System (INIS)

    Using three-dimensional time-of-flight (3D TOF) MRA with a 1.5 T MRI system, we assessed the capability of MRA to detect intracranial occlusive lesions. Ten observers evaluated MRA images of 78 patients (including 33 cases with 57 intracranial occlusive lesions) using maximum intensity projection (MIP) images alone, MIP+selective MIP images, and MIP+selective MIP+original images. By receiver operating characteristic (ROC) analysis of the ability to detect the 33 patients with occlusive lesions, the sensitivity of MIP images was 89±7% (mean ±S. D.) while the specificity was 80%. The sensitivity was significantly higher than that for detecting aneurysms (74±8%). Adding selective MIP and original images to MIP images did not improve the sensitivity in detecting occlusive lesions. Sensitivity for detection of severe stenosis and occlusion was over 75%, which was considered to be satisfactory to identity the lesions, while that for mild stenosis was 44%. Although the sensitivity did not show any difference between internal coroted (IC) and middle cerebral artery stenosis (MCA), false positive IC lesions were more frequent. These results indicate that the sensitivity of MRA in detecting occlusive lesions is generally satisfactory, while care should be taken in diagnosing mild stenotic lesions and lesions in the IC. (author)

  12. Tuberculoma cerebral Cerebral tuberculoma

    OpenAIRE

    ELIZABETH CLARA BARROSO; TÂNIA REGINA BRÍGIDO DE OLIVEIRA; ANA MARIA DANTAS DO AMARAL; VALÉRIA GÓES FERREIRA PINHEIRO; ANA LÚCIA DE OLIVEIRA SOUSA

    2002-01-01

    Relata-se o caso de paciente com crises convulsivas de início recente. A tomografia computadorizada cerebral evidenciou imagem sugestiva de lesão expansiva metastática frontoparietal direita. A investigação de tumor primário ou outra doença foi negativa e o exame histopatológico do tecido cerebral diagnosticou tuberculoma. As convulsões foram controladas com a associação de hidantoína 300mg/dia ao esquema específico, utilizado por 18 meses. A tuberculose do sistema nervoso central representa ...

  13. Neuroimaging of cerebral vasculitis; Bildgebung zerebraler Vaskulitiden

    Energy Technology Data Exchange (ETDEWEB)

    Wengenroth, M. [Universitaetsklinikum Schleswig-Holstein, Campus Luebeck, Institut fuer Neuroradiologie, Luebeck (Germany); Klinikum der Ludwig-Maximilians-Universitaet, Institut fuer klinische Radiologie, Muenchen (Germany); Saam, T. [Klinikum der Ludwig-Maximilians-Universitaet, Institut fuer klinische Radiologie, Muenchen (Germany); Haehnel, S. [Universitaetsklinikum Heidelberg, Abteilung Neuroradiologie, Heidelberg (Germany)

    2016-01-15

    Cerebral vasculitis can have a variety of origins. Furthermore, there are no vasculitis-specific symptoms or imaging signs and vasculitis of the CNS can mimic many other neurological diseases, which require different treatment approaches. Thus, the clinical and radiological diagnosis of cerebral vasculitis is challenging. Magnetic resonance imaging (MRI) and MR angiography (MRA) should be the radiological imaging methods of choice to assess the degree of parenchymal damage and to detect vessel wall changes. If the results are unclear digital subtraction angiography (DSA) should be pursued in order to also detect changes in medium sized vessels. Vasculitis of small vessels cannot be detected by vascular imaging and requires brain or leptomeningeal biopsy. In this review we present the current diagnostic approach and a variety of imaging findings in cerebral vasculitis and discuss the main radiological differential diagnoses. (orig.) [German] Die zerebrale Vaskulitis kann viele Ursachen haben. Daher ist die klinische und radiologische Diagnose schwierig, auch weil es etliche vaskulitistypische Symptome und MR-Befunde bei anderen Erkrankungen gibt. Die ZNS-Vaskulitis kann zahlreiche andere neurologische Erkrankungen imitieren, die unterschiedlicher Therapie beduerfen. MRT und MR-Angiographie (MRA) sind die Verfahren der Wahl, mit denen die radiologische Diagnostik begonnen werden sollte, um den Parenchymschaden und den Gefaessbefall zu beurteilen. Bei unklaren Befunden kann eine digitale Subtraktionsangiographie (DSA) ergaenzt werden, um auch mittelgrosse Gefaesse beurteilen zu koennen. Der Befall kleiner Gefaesse kann nur bioptisch nachgewiesen werden. In der folgenden Uebersicht stellen wir das diagnostische Herangehen bei zerebraler Vaskulitis vor, praesentieren zahlreiche Befunde und diskutieren die wichtigsten radiologischen Differenzialdiagnosen. (orig.)

  14. Vessel enhancing diffusion: a scale space representation of vessel structures.

    Science.gov (United States)

    Manniesing, Rashindra; Viergever, Max A; Niessen, Wiro J

    2006-12-01

    A method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffusion. The method performs better than most of the existing techniques in visualizing vessels with varying radii and in enhancing vessel appearance. A diameter study on phantom data shows that VED least affects the accuracy of diameter measurements. It is shown that using VED as a preprocessing step improves level set based segmentation of the cerebral vasculature, in particular segmentation of the smaller vessels of the vasculature. PMID:16876462

  15. Marine bird specimen and other data from various small vessels as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 24 June 1976 to 11 August 1980 (NODC Accession 8200073)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine bird specimen and other data were collected from various small vessels from 24 June 1976 to 11 August 1980. Data were collected by the University of Alaska -...

  16. Marine animal sighting and census data from various small vessels as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 26 July 1982 to 24 August 1982 (NODC Accession 8300139)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine animal sighting and census data were collected from various small vessels from 26 July 1982 to 24 August 1982. Data were collected by the University of...

  17. Effects of Electroacupuncturing Ren Vessel on Protein and mRNA Expression of bFGF After Focal Cerebral Ischemia-Reperfusion in Rats%电针任脉经穴对脑缺血再灌注大鼠脑内bFGF蛋白及bFGFmRNA表达的影响

    Institute of Scientific and Technical Information of China (English)

    杨卓欣; 马晓明; 于海波; 吴志强; 皮敏; 王玲; 郑晓斌

    2009-01-01

    Objective:To observe the effects of electroacupuncturing ren vessel on protein and mRNA expression of bF-GF after focal cerebral ischemia-reperfusion in rats. Methods : Cerebral ischemia - reperfusion injury model was induced by the method of nylon monofilament embolism. 72 rats were randomly divided into sham operation group(Sham) ,ischemia -reperfusion model group (MCAO) and ischemia-reperfusion injury with electroacupuncturing ten vessel treatment group (R). Protein and mRNA expression of bFGF in subventricular zone(SVZ) and Dentate Gyms(DG) were observed by im-munohistochemistry and in situ hybridization. Results:Compared with Sham group, more positive cells of hFGF protein and bFGFmRNA could be observed in MCAO group. And there are statistic difference at 7 days and 14 days after cerebral is-chemia-reperfusion(P 0. 05). There was statistic difference between MCAO and R group at 14 days and 28 days after cerebral isehemia-reperfusion(P 0.05),造模后14天及28天差异均有统计学意义(P<0.05).结论:电针任脉经穴能够上调脑缺血再灌注大鼠脑内bF-GF蛋白及bFGFinRNA表达,这可能是电针任脉促进脑缺血损伤后神经修复的保护机制之一.

  18. RELAP5 Analyses of ROSA/LSTF Experiments on AM Measures during PWR Vessel Bottom Small-Break LOCAs with Gas Inflow

    OpenAIRE

    Takeshi Takeda

    2014-01-01

    RELAP5 code posttest analyses were performed on ROSA/LSTF experiments that simulated PWR 0.2% vessel bottom small-break loss-of-coolant accidents with different accident management (AM) measures under assumptions of noncondensable gas inflow and total failure of high-pressure injection system. Depressurization of and auxiliary feedwater (AFW) injection into the secondary-side of both steam generators (SGs) as the AM measures were taken 10 min after a safety injection signal. The primary depre...

  19. 3D-Gd-DTPA MR angiography of cerebral blood vessels: A comparison with conventional 3D-MR subtraction angiography

    International Nuclear Information System (INIS)

    Subtraction angiography based on 3D fast imaging techniques using rephasing and dephasing gradient pulses is widely used, resulting in angiograms which closely correlate with DSA. Similar angiograms can be obtained with 3D-gradient echo techniques before and after the administration of Gadolinium (Gd)-DTPA (0.1-0.2 mmol/kg) followed by image subtraction. As Gd-DTPA does not penetrate the blood-brain barrier, brain imaging is not altering by the contrast agent. Both techniques were compared in patients wihout vascular disease, venous sinus thrombosis, AV malformation and aneurysm. With both techniques the cerebro-vascular system was imaged favoring the venous system because of the more constant flow velocity and the lack of ECG synchronization. Gd-DTPA offers the advantage of the higher signal-to-noise ratio and is hampered by background superposition due to Gd-DTPA enhancement in non brain tissue. With both techniques vessels down to 1 mm can be imaged. (orig.)

  20. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization

    Directory of Open Access Journals (Sweden)

    Birgit Huber

    2016-04-01

    Full Text Available Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of approximately 100 µm or 200 µm. We established a rinsing protocol to remove remaining cytotoxic substances from the photo-cured PA and applied thio-modified heparin and RGDC-peptides to functionalize the PA surface for enhanced endothelial cell adhesion. A rotating seeding procedure was introduced to ensure homogenous endothelial monolayer formation at the inner luminal tube wall. We showed that endothelial cells stayed viable and adherent and aligned along the medium flow under fluid-flow conditions comparable to native capillaries. The combined technology approach comprising of freeform additive manufacturing (AM, biomimetic design, cytocompatible materials which are applicable to AM, and biofunctionalization of AM constructs has been introduced as BioRap® technology by the authors.

  1. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization.

    Science.gov (United States)

    Huber, Birgit; Engelhardt, Sascha; Meyer, Wolfdietrich; Krüger, Hartmut; Wenz, Annika; Schönhaar, Veronika; Tovar, Günter E M; Kluger, Petra J; Borchers, Kirsten

    2016-01-01

    Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA) for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of approximately 100 µm or 200 µm. We established a rinsing protocol to remove remaining cytotoxic substances from the photo-cured PA and applied thio-modified heparin and RGDC-peptides to functionalize the PA surface for enhanced endothelial cell adhesion. A rotating seeding procedure was introduced to ensure homogenous endothelial monolayer formation at the inner luminal tube wall. We showed that endothelial cells stayed viable and adherent and aligned along the medium flow under fluid-flow conditions comparable to native capillaries. The combined technology approach comprising of freeform additive manufacturing (AM), biomimetic design, cytocompatible materials which are applicable to AM, and biofunctionalization of AM constructs has been introduced as BioRap(®) technology by the authors. PMID:27104576

  2. The Susceptibility Vessel Sign of the Middle Cerebral Artery on the T2-Weighted Gradient Echo Imaging: Semi-quantification to Predict the Response to Multimodal Intra-Arterial Thrombolysis

    Energy Technology Data Exchange (ETDEWEB)

    Youn, Sung Won [Catholic University of Daegu Medical Center, Daegu (Korea, Republic of); Jung, Cheol Kyu; Choi, Byung Se; Kim, Jae Hyoung; Kwon, O Ki; Han, Moon Ku; Bae, Hee Joon [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Kwon, Bae Ju [Kwandong University Myongji Hospital, Goyang (Korea, Republic of); Han, Moon Hee [Seoul National University Hospital, Seoul (Korea, Republic of)

    2011-01-15

    We wanted to determine whether or not the 'susceptibility asymmetry index' (SAI) of acute stroke on the T2-weighted image is related with successful recanalization using multimodal intra-arterial thrombolysis (IAT). The 81 patients who underwent multimodal IAT for middle cerebral artery (MCA) territory acute stroke were included in this retrospective study. The multimodal IAT included intra-arterial urokinase infusion, clot disruption by a microwire, microcatheter and balloon manipulation, and balloon angioplasty and/or stenting for the flow-limiting stenosis. The diameter of the susceptibility vessel sign was measured on the T2-weighted gradient echo imaging (GRE), and the diameter of the contralateral normal MCA at the corresponding level was measured on magnetic resonance angiography (MRA): the ratio between these two diameters was defined as the susceptibility asymmetry index. The relation between the TICI (Thrombolysis In Cerebral Infarction) score of 2-3 after multimodal IAT and the SAI was assessed. The receiver operating characteristic (ROC) curve analysis was performed on the SAI to predict a TICI score of 2-3 after multimodal IAT. The mean SAI of 81 patients was 1.66 {+-} 0.66. Seventy nine percent of the patients had a TICI of 2-3 after multimodal IAT. According to the ROC curve analysis, an SAI less than 1.3 was optimal for predicting the presence of stenotic lesion after recanalization (area under the curve: 0.821, sensitivity: 88.2%, specificity: 69.8%, p=0.0001), and the SAI {<=}1.61 (area under the curve: 0.652, sensitivity: 60.9%, specificity: 70.6%, p=0.0226) could predict a TICI score of 2-3. The TICI score of 2-3 after multimodal IAT was achieved in 88.6% of the cases with a SAI {<=} 1.61 and in 67.6% of the cases with a SAI >1.61 (p=0.028). The lower SAI on T2-GRE could predict stenotic lesion and successful recanalization after performing IAT

  3. Cerebral Palsy

    Science.gov (United States)

    Cerebral palsy is a group of disorders that affect a person's ability to move and to maintain balance ... do not get worse over time. People with cerebral palsy may have difficulty walking. They may also have ...

  4. Preferentially affected sites of cerebral arteriosclerosis in vascular dementia of Binswanger type. A study of MRI and MR angiography

    International Nuclear Information System (INIS)

    MRI and MR angiography (MRA) were analyzed to evaluate the preferential sites of cerebral arteriosclerosis in 129 normal controls and 27 patients with vascular dementia of Binswanger type (BVD; mean age 75.0 years). Small vessel disease, indicated as advanced high intensity areas on T2-weighted MRI, increased with advancing age, while large vessel sclerosis detected with MRA did not increase after the age of 80 years. Large vessel sclerosis was not always accompanied with advanced high intensity areas. Large vessel sclerosis was found in 12 (44.4%) of 27 patients with BVD, and was as common as that of the controls of the eighth decade. Large vessel sclerosis was frequently seen in the cases suffering from BVD below 70 years of age or with hypertension. In conclusion, patients with BVD develop cerebral arteriosclerosis more preferentially in the small vessels rather than the large vessels especially in aged cases, of which incidence is similar to that of the normal controls over 80 years of age. (author)

  5. Cerebral Atrophy

    Science.gov (United States)

    ... Alzheimer’s disease, Pick’s disease, and fronto-temporal dementia cerebral palsy , in which lesions (damaged areas) may impair motor ... lead to cerebral atrophy. NIH Patient Recruitment for Cerebral Atrophy Clinical Trials ... by: Office of Communications and Public Liaison National Institute of Neurological Disorders ...

  6. Adrenergic-induced enhancement of brain barrier system permeability to small nonelectrolytes: choroid plexus versus cerebral capillaries

    International Nuclear Information System (INIS)

    Acute hypertension induced by adrenergic agents opens up the blood-CSF barrier (choroid plexus) to nonelectrolyte and protein tracers. Sprague-Dawley adult rats anesthetized with ketamine were given an intravenous bolus of either epinephrine (10 micrograms/kg), phenylephrine (100 micrograms/kg), isoproterenol (10 micrograms/kg), or D,L-amphetamine (2 mg/kg). Tracers were injected simultaneously with test agents, and the animals killed 10 min later. Epinephrine raised MABP by 57 mm Hg, to a peak pressure of 160 mm Hg; and it increased the volume of distribution (Vd) of urea, mannitol, and 125I-bovine serum albumin in CSF by 1.5-, 2.7-, and 30-fold, respectively. There was enhanced uptake by lateral and fourth ventricle choroid plexuses, cerebral cortex, cerebellum, medulla, and thalamus. Phenylephrine also elevated MABP to 160 mm Hg, but it increased permeation of tracers into CSF (and several brain regions) to a lesser extent than epinephrine, attributable to protective vasoconstriction associated with alpha-agonist activity. Ratio analysis of Vd data provides evidence that augmented permeation of nonelectrolyte tracers in acute hypertension occurs predominantly by diffusion rather than vesicular transport. It is postulated that elevated MABP distends the central cores of choroid plexus villi and cerebral capillaries, with resultant stretching and opening of tight junctions in both barrier systems; with less hindrance to diffusion, urea and mannitol are cleared at rates closer to free diffusion. Neither isoproterenol (decreased MABP by 40 mm Hg) nor amphetamine (did not alter MABP) significantly opened the choroid plexus or blood-brain barrier to tracers

  7. Glycopyrrolate abolishes the exercise-induced increase in cerebral perfusion in humans

    DEFF Research Database (Denmark)

    Seifert, Thomas; Fisher, James P; Young, Colin N;

    2010-01-01

    Brain blood vessels contain muscarinic receptors that are important for cerebral blood flow (CBF) regulation, but whether a cholinergic receptor mechanism is involved in the exercise-induced increase in cerebral perfusion or affects cerebral metabolism remains unknown. We evaluated CBF and cerebr...... abolished by glycopyrrolate (P <0.05). Thus, during both cycling and static handgrip, a cholinergic receptor mechanism is important for the exercise-induced increase in cerebral perfusion without affecting the cerebral metabolic rate for oxygen....

  8. Loop Modeling Forward and Feedback Analysis in Cerebral Arteriovenous Malformation

    OpenAIRE

    Y. Kiran Kumar; Shashi.B.Mehta; Manjunath Ramachandra

    2013-01-01

    Cerebral Arteriovenous Malformation (CAVM) hemodynamic in disease condition results changes in the flow and pressure level in blood vessels. Cerebral Arteriovenous Malformation (CAVM) is an abnormal shunting of vessels between arteries and veins. It is one of the common Brain disorder. In general, the blood flows of cerebral region are from arteries to veins through capillary bed. This paper is focus on the creation of a new electrical model for spiral loop structures that will simulate the p...

  9. Contribution to the determination of microstructural parameters from small angle scattering experiments at reactor pressure vessel steels

    International Nuclear Information System (INIS)

    Usually, the microstructure cannot be absolutely surely reconstructed from the small angle scattering pattern produced by it. The small angle neutron scattering curves measured at four C-poor ternary iron alloys were used to demonstrate the effect of the analysis method and the applied assumption on the microstructure analysis. Apart from the mean size of the scatterer, the size distribution as well as the shape of the scatterer affect the results. As a consequence, even well-proved methods as the indirect transformation method developed by Glatter can fail. The application of additional evaluation procedures or the use of information obtained by non-small angle scattering methods increases the chance to derive plausible structure models. In the paper a fit two-parameter method, the ratio between nuclear and magnetic scattering cross section and results from atom probe field ion microscopy are used for that. In this way it is shown that one of the four alloys exhibits another type of irradiation defects. Furthermore, modelling of the mechanical behaviours can also be helpful. (orig.)

  10. Effects of estrogen on cerebrovascular function: age-dependent shifts from beneficial to detrimental in small cerebral arteries of the rat.

    Science.gov (United States)

    Deer, Rachel R; Stallone, John N

    2016-05-15

    In the present study, interactions of age and estrogen in the modulation of cerebrovascular function were examined in small arteries vasoconstriction was attenuated in ovariectomized + estrogen-replaced, multigravid adult rats (5-6 mo; MAE) but potentiated in older ovariectomized + estrogen-replaced, reproductively senescent rats (12-14 mo; RSE). SC560 and NS398 reduced reactivity similarly in ovariectomized multigravid adult rats (5-6 mo; MAO) and ovariectomized reproductively senescent rat (12-14 mo; RSO). In MAE, reactivity to VP was reduced to a greater extent by SC560 than by NS398; however, in RSE, this effect was reversed. VP-stimulated PGI2 was increased by estrogen, yet reduced by age. VP-stimulated TXA2 was increased by estrogen and age in RSE but did not differ in MAO and RSO. Taken together, these data reveal that the vascular effects of estrogen are distinctly age-dependent in F rats. In younger MA, beneficial and protective effects of estrogen are evident (decreased vasoconstriction, increased dilator prostanoid function). Conversely, in older RS, detrimental effects of estrogen begin to be manifested (enhanced vasoconstriction and CP function). These findings may lead to age-specific estrogen replacement therapies that maximize beneficial and minimize detrimental effects of this hormone on small cerebral arteries that regulate blood flow. PMID:26993224

  11. Tuberculoma cerebral Cerebral tuberculoma

    Directory of Open Access Journals (Sweden)

    ELIZABETH CLARA BARROSO

    2002-01-01

    Full Text Available Relata-se o caso de paciente com crises convulsivas de início recente. A tomografia computadorizada cerebral evidenciou imagem sugestiva de lesão expansiva metastática frontoparietal direita. A investigação de tumor primário ou outra doença foi negativa e o exame histopatológico do tecido cerebral diagnosticou tuberculoma. As convulsões foram controladas com a associação de hidantoína 300mg/dia ao esquema específico, utilizado por 18 meses. A tuberculose do sistema nervoso central representa 5-15% das formas extrapulmonares e é reconhecida como de alta letalidade. Apresentação tumoral como a relatada é rara, particularmente em imunocompetentes. Quando tratada, pode ter bom prognóstico e deve entrar sempre no diagnóstico diferencial de massas cerebrais.It is reported a case of a previously healthy man with seizures of sudden onset. A contrast head computerized tomogram (CT showed a right frontoparietal expanding lesion suggesting to be metastatic. No prior disease was found on investigation. The histologic exam of the brain revealed tuberculoma. The seizures were controlled with Hidantoin 300 mg/day and antituberculosis chemotherapy for 18 months. Central nervous system tuberculosis (5-15% of the extrapulmonary forms is highly lethal. The case reported herein is specially rare in immunocompetent patients. It may have good prognosis and should be considered in the differential diagnosis of brain tumours.

  12. 血糖水平对急性脑血管病患者神经功能恢复的影响%The influence of blood sugar level on the recovery of patients' nerve function of acute cerebral vessel disease

    Institute of Scientific and Technical Information of China (English)

    郝淑梅; 石寄平; 谢艳萍

    2001-01-01

    @@ Background:Diabetes mellitus is one of risk factors leading to acute cerebral vessel disease(ACVD),and people have paid more attention to the fact that increase of blood sugar level after ACVD can aggravate nerve system impairment. Objective:To study the influence of blood sugar level increase on the recovery of nerve function of ACVD. Design:To make retrospective analysis on the relationship between prognosis and ACVD blood sugar level increase,the 157 patients lived in our hospital between March 1995 and March 2001.

  13. The cerebral hemodynamics of normotensive hypovolemia during lower-body negative pressure

    Science.gov (United States)

    Giller, C. A.; Levine, B. D.; Meyer, Y.; Buckey, J. C.; Lane, L. D.; Borchers, D. J.

    1992-01-01

    Although severe hypovolemia can lead to hypotension and neurological decline, many patients with neurosurgical disorders experience a significant hypovolemia while autonomic compensatory mechanisms maintain a normal blood pressure. To assess the effects of normotensive hypovolemia upon cerebral hemodynamics, transcranial Doppler ultrasound monitoring of 13 healthy volunteers was performed during graded lower-body negative pressure of up to -50 mm Hg, an accepted laboratory model for reproducing the physiological effects of hypovolemia. Middle cerebral artery flow velocity declined by 16% +/- 4% (mean +/- standard error of the mean) and the ratio between transcranial Doppler ultrasound pulsatility and systemic pulsatility rose 22% +/- 8%, suggesting cerebral small-vessel vasoconstriction in response to the sympathetic activation unmasked by lower-body negative pressure. This vasoconstriction may interfere with the autoregulatory response to a sudden fall in blood pressure, and may explain the common observation of neurological deficit during hypovolemia even with a normal blood pressure.

  14. Endovascular glue embolization of dissecting aneurysm of type-3 accessory middle cerebral artery: A contralateral approach.

    Science.gov (United States)

    Parthasarathy, Rajsrinivas; Goel, Gaurav; Gupta, Vipul; Narang, Karanjit Singh; Anand, Saurabh; Jha, Ajaya Nand

    2015-12-01

    Pediatric intracranial aneurysms are rare with a reported prevalence of 0.5-4.6%. Likewise, anomalous arterial patterns are uncommon in the cerebral circulation. Recognition of these variations and knowledge of vascular territory forms the key to managing pathological conditions associated with these anomalous vessels. Ruptured dissecting aneurysm of type-3 accessory middle cerebral artery (aMCA) has not been reported in the pediatric age group. In addition to type-3 aMCA, the child in this case report had an ipsilateral type-1 aMCA with cortical supply. We describe the patterns of accessory MCA and their vascular territory, state the perplexity involved in deciding the best management strategy, and describe the technical approach we undertook to catheterize this small caliber recurrent artery (type-3 aMCA) originating at an acute angle from the anterior cerebral artery. PMID:26508091

  15. Mechanistic insights into a TIMP3-sensitive pathway constitutively engaged in the regulation of cerebral hemodynamics

    Science.gov (United States)

    Capone, Carmen; Dabertrand, Fabrice; Baron-Menguy, Celine; Chalaris, Athena; Ghezali, Lamia; Domenga-Denier, Valérie; Schmidt, Stefanie; Huneau, Clément; Rose-John, Stefan; Nelson, Mark T; Joutel, Anne

    2016-01-01

    Cerebral small vessel disease (SVD) is a leading cause of stroke and dementia. CADASIL, an inherited SVD, alters cerebral artery function, compromising blood flow to the working brain. TIMP3 (tissue inhibitor of metalloproteinase 3) accumulation in the vascular extracellular matrix in CADASIL is a key contributor to cerebrovascular dysfunction. However, the linkage between elevated TIMP3 and compromised cerebral blood flow (CBF) remains unknown. Here, we show that TIMP3 acts through inhibition of the metalloprotease ADAM17 and HB-EGF to regulate cerebral arterial tone and blood flow responses. In a clinically relevant CADASIL mouse model, we show that exogenous ADAM17 or HB-EGF restores cerebral arterial tone and blood flow responses, and identify upregulated voltage-dependent potassium channel (KV) number in cerebral arterial myocytes as a heretofore-unrecognized downstream effector of TIMP3-induced deficits. These results support the concept that the balance of TIMP3 and ADAM17 activity modulates CBF through regulation of myocyte KV channel number. DOI: http://dx.doi.org/10.7554/eLife.17536.001 PMID:27476853

  16. Cerebral Palsy

    Science.gov (United States)

    ... 1 • 2 • 3 For Teens For Kids For Parents MORE ON THIS TOPIC Cerebral Palsy: Keith's Story Physical Therapy I Have Cerebral Palsy. Can I Babysit? Body Image and Self-Esteem Contact Us Print Resources Send to a friend ...

  17. Cerebral versus systemic hemodynamics during graded orthostatic stress in humans

    Science.gov (United States)

    Levine, B. D.; Giller, C. A.; Lane, L. D.; Buckey, J. C.; Blomqvist, C. G.

    1994-01-01

    estimated from changes in the blood flow velocity in the middle cerebral artery (VMCA) using transcranial Doppler. Pulsatility (systolic minus diastolic/mean velocity) normalized for systemic arterial pressure pulsatility was used as an index of distal cerebral vascular resistance. End-tidal PACO2 was closely monitored during LBNP. From rest to maximal LBNP before the onset of symptoms or systemic hypotension, Qc and FBF decreased by 29.9% and 34.4%, respectively. VMCA decreased less, by 15.5% consistent with a smaller decrease in CBF. Similarly, SVR and FVR increased by 62.8% and 69.8%, respectively, whereas pulsatility increased by 17.2%, suggestive of a mild degree of small-vessel cerebral vasoconstriction. Seven of 13 subjects had presyncope during LBNP, all associated with a sudden drop in BP (29 +/- 9%). By comparison, hyperventilation alone caused greater changes in VMCA (42 +/- 2%) and pulsatility but never caused presyncope. In a separate group of 3 subjects, superimposition of hyperventilation during highlevel LBNP caused a further decrease in VMCA (31 +/- 7%) but no change in BP or level of consciousness. CONCLUSIONS: We conclude that cerebral vasoconstriction occurs in healthy humans during graded reductions in central blood volume caused by LBNP. However, the magnitude of this response is small compared with changes in SVR or FVR during LBNP or other stimuli known to induce cerebral vasoconstriction (hypocapnia). We speculate that this degree of cerebral vasoconstriction is not by itself sufficient to cause syncope during orthostatic stress. However, it may exacerbate the decrease in CBF associated with hypotension if hemodynamic instability develops.

  18. A study on the pathogenesis of human cerebral malaria and cerebral babesiosis

    Directory of Open Access Journals (Sweden)

    Masamichi Aikawa

    1992-01-01

    Full Text Available Cerebral complications are important, but poorly understood pathological features of infections caused by some species of Plasmodium and Babesia. Patients dying from P. falciparum were classified as cerebral or non-cerebral cases according to the cerebral malaria coma scale. Light microscopy revealed that cerebral microvessels of cerebral malaria patients were field with a mixture of parazited and unparazited erythrocytes, with 94% of the vessels showing parasitized red blood cell (PRBC sequestration. Some degree of PRBC sequestration was also found in non-cerebral malaria patients, but the percentage of microvessls with sequestered PRBC was only 13% Electron microscopy demonstrated knobs on the membrane of PRBC that formed focal junctions with the capillary endothelium. A number of host cell molecules such as CD36, thrombospondim (TSP and intracellular adhesion molecule I (ICAM-1 may function as endothelial cell surfacereports for P. falciparum-infected erythrocytes. Affinity labeling of CD36 and TSP to the PRBC surface showed these molecules specifically bind to the knobs. Babesia bovis infected erythrocytes procedure projections of the erythrocyte membrane that are similar to knobs. When brain tissue from B. bovis-infected cattle was examined, cerebral capillaries were packed with PRBC. Infected erythrocytes formed focal attachments with cerebral endothelial cells at the site of these knob-like projections. These findings indicate that cerebral pathology caused by B. bovis is similar to human cerebral malaria. A search for cytoadherence proteins in the endothelial cells may lead to a better understanding of the pathogenisis of cerebral babesiosis.

  19. Cerebral aterial spasm. I. Adrenergic mechanism in experimental cerebral vasospasm.

    Directory of Open Access Journals (Sweden)

    Morooka,Hiroshi

    1978-04-01

    Full Text Available This study demonstrates that an adrenergic mechanism plays an important role in producing the delayed cerebral vasospasm which follows subarachnoid hemorrhage. Results were as follows: 1. Experimental subarachnoid hemorrhage (SAH was produced by injection of fresh arterial blood into the cisterna magna in cats. The cerebral vasospasm was shown angiographically to be biphasic in nature: immediate constriction lasting 1 h and marked prolonged spasm occurring between the 3rd and 5th day after SAH. The amount of noradrenaline (NA and dopamine-beta-hydroxylase (DBH activity decreased over a period of 24 h both within the wall of the basilar artery and in the locus ceruleus and then gradually increased, reaching a maximum on the 3rd day after SAH. 2. Topical application of spasmogenic substances (NA and blood produced a marked constriction of the hypersensitive basilar artery on the 3rd day after SAH. 3. 6-Hydroxydopamine (6-OHDA injection into the cisterna magna produced prolonged vasocilatation. The dilated vessel responded with mild transient constriction after the topical application of NA or fresh blood. DBH activity and NA concentration in the vessels, locus ceruleus and medial hypothalamus decreased markedly on the 3rd day after the cisternal injection of 6-OHDA. 4. Various spasmogenic substances (i.e. serotonin, NA, prostaglandins and methemoglobin were measured in a mixture of equal volume of CSF and blood in cats. ONly the serotonin in the mixed fluid produced vasoconstriction. Spasmogenic substances decreased markedly in the mixed fluid incubated for 3 days at 37 degrees C, and none of these substances apart from methemoglobin was present in a concentration sufficient to produce constriction of vessels. 5. These results suggest that early spasm is induced by serotonin around the arteries of the cranial base, and delayed spasm might be caused by hyperreaction of cerebral vessels to spasmogenic substances such as methemoglobin, during the

  20. Detection of small human cerebral cortical lesions with MRI under different levels of Gaussian smoothing: applications in epilepsy

    Science.gov (United States)

    Cantor-Rivera, Diego; Goubran, Maged; Kraguljac, Alan; Bartha, Robert; Peters, Terry

    2010-03-01

    The main objective of this study was to assess the effect of smoothing filter selection in Voxel-Based Morphometry studies on structural T1-weighted magnetic resonance images. Gaussian filters of 4 mm, 8 mm or 10 mm Full Width at High Maximum are commonly used, based on the assumption that the filter size should be at least twice the voxel size to obtain robust statistical results. The hypothesis of the presented work was that the selection of the smoothing filter influenced the detectability of small lesions in the brain. Mesial Temporal Sclerosis associated to Epilepsy was used as the case to demonstrate this effect. Twenty T1-weighted MRIs from the BrainWeb database were selected. A small phantom lesion was placed in the amygdala, hippocampus, or parahippocampal gyrus of ten of the images. Subsequently the images were registered to the ICBM/MNI space. After grey matter segmentation, a T-test was carried out to compare each image containing a phantom lesion with the rest of the images in the set. For each lesion the T-test was repeated with different Gaussian filter sizes. Voxel-Based Morphometry detected some of the phantom lesions. Of the three parameters considered: location,size, and intensity; it was shown that location is the dominant factor for the detection of the lesions.

  1. Cerebral palsy.

    Science.gov (United States)

    Graham, H Kerr; Rosenbaum, Peter; Paneth, Nigel; Dan, Bernard; Lin, Jean-Pierre; Damiano, Diane L; Becher, Jules G; Gaebler-Spira, Deborah; Colver, Allan; Reddihough, Dinah S; Crompton, Kylie E; Lieber, Richard L

    2016-01-01

    Cerebral palsy is the most common cause of childhood-onset, lifelong physical disability in most countries, affecting about 1 in 500 neonates with an estimated prevalence of 17 million people worldwide. Cerebral palsy is not a disease entity in the traditional sense but a clinical description of children who share features of a non-progressive brain injury or lesion acquired during the antenatal, perinatal or early postnatal period. The clinical manifestations of cerebral palsy vary greatly in the type of movement disorder, the degree of functional ability and limitation and the affected parts of the body. There is currently no cure, but progress is being made in both the prevention and the amelioration of the brain injury. For example, administration of magnesium sulfate during premature labour and cooling of high-risk infants can reduce the rate and severity of cerebral palsy. Although the disorder affects individuals throughout their lifetime, most cerebral palsy research efforts and management strategies currently focus on the needs of children. Clinical management of children with cerebral palsy is directed towards maximizing function and participation in activities and minimizing the effects of the factors that can make the condition worse, such as epilepsy, feeding challenges, hip dislocation and scoliosis. These management strategies include enhancing neurological function during early development; managing medical co-morbidities, weakness and hypertonia; using rehabilitation technologies to enhance motor function; and preventing secondary musculoskeletal problems. Meeting the needs of people with cerebral palsy in resource-poor settings is particularly challenging. PMID:27188686

  2. RELAP5 Analyses of ROSA/LSTF Experiments on AM Measures during PWR Vessel Bottom Small-Break LOCAs with Gas Inflow

    Directory of Open Access Journals (Sweden)

    Takeshi Takeda

    2014-01-01

    Full Text Available RELAP5 code posttest analyses were performed on ROSA/LSTF experiments that simulated PWR 0.2% vessel bottom small-break loss-of-coolant accidents with different accident management (AM measures under assumptions of noncondensable gas inflow and total failure of high-pressure injection system. Depressurization of and auxiliary feedwater (AFW injection into the secondary-side of both steam generators (SGs as the AM measures were taken 10 min after a safety injection signal. The primary depressurization rate of 55 K/h caused rather slow primary depressurization being obstructed by the gas accumulation in the SG U-tubes after the completion of accumulator coolant injection. Core temperature excursion thus took place by core boil-off before the actuation of low-pressure injection (LPI system. The fast primary depressurization by fully opening the relief valves in both SGs with continuous AFW injection led to long-term core cooling by the LPI actuation even under the gas accumulation in the SG U-tubes. The code indicated remaining problems in the predictions of break flow rate during two-phase flow discharge period and primary pressure after the gas inflow. Influences of the primary depressurization rate with continuous AFW injection onto the long-term core cooling were clarified by the sensitivity analyses.

  3. An experimental study on effective depressurization actions for PWR vessel bottom small break LOCA with HPI failure and gas inflow (ROSA-V test SB-PV-04)

    International Nuclear Information System (INIS)

    A small break loss-of-coolant accident (SBLOCA) experiment was conducted at the Large Scale Test Facility (LSTF) of ROSA-V program to study effects of accident management (AM) measures on core cooling, which are important in case of total failure of high pressure injection (HPI) system during an SBLOCA at a pressurized water reactor (PWR). The LSTF is a full-height and 1/48 volume-scaled facility simulating a 4-loop Westing-house-type PWR (3423 MWt). The experiment, SB-PV-04, simulated a PWR vessel bottom SBLOCA with a rupture of ten instrument-tubes which is equivalent to 0.2% cold leg break. It is clarified that AM actions with steam generator (SG) rapid depressurization by fully opening relief valves and auxiliary feedwater supply are effective to avoid core uncovery by actuating the low pressure injection (LPI) system though the primary depressurization is degraded by non-condensable gas inflow to the primary loops from the accumulator injection system. The effective core cooling was established by the rapid depressurization which contributed to preserve larger primary coolant mass than in the previous experiment (SB-PV-03) which was conducted with smaller primary cooling rate of -55 K/h as AM actions. (author)

  4. Experimental study on secondary depressurization action for PWR vessel bottom small break LOCA with HPI failure and gas inflow (ROSA-V/LSTF test SB-PV-03)

    International Nuclear Information System (INIS)

    A small break loss-of-coolant accident (SBLOCA) experiment was conducted at the Large Scale Test Facility (LSTF) of ROSA-V program to study effects of accident management (AM) measures on core cooling, which is important in case of high pressure injection (HPI) system failure during an SBLOCA at a pressurized water reactor (PWR). The LSTF is a full-height and 1/48 volume-scaled facility simulating 4-loop Westinghouse-type PWR (3423 MWt). The experiment, SB-PV-03, simulated a PWR vessel bottom SBLOCA with a rupture of ten instrument-tubes which is equivalent to 0.2% cold leg break. Total HPI failure, non-condensable gas inflow from accumulator injection system (AIS) and operator AM actions on steam generator (SG) secondary depressurization at a rate of -55 K/h and auxiliary feedwater (AFW) supply for 30 minutes were assumed as experiment conditions. It is clarified that the AM actions are effective on primary system depressurization until the end of AIS injection at 1.6 MPa, but thereafter become less effective due to inflow of the non-condensable gas, resulting in delay of low pressure injection (LPI) actuation and whole core heatup under continuous water discharge through the bottom break. The report describes these thermohydraulic phenomena related with transient primary coolant mass and AM actions in addition to estimation of non-condensable gas behavior which affected primary-to-secondary heat transfer. (author)

  5. Influence of paravertebrals miorelaxation on cerebral hemodynamics of sportsmen

    Directory of Open Access Journals (Sweden)

    Syshko D.V.

    2014-01-01

    Full Text Available Purpose: Paravertebrals miorelaxation was the complex of exercises in a water environment directed on the decline of tone of paravertebral muscles. Material: Before and after it was used of paravertebrals miorelaxation registered the indexes of reoentsefalografics at the sportsmen engaged in the Greek-Roman fight (n=22 by football (n=24 and heavy athletics (n=25. Results : The changes, that have been determined at the wrestlers, was in the form of increasing tone of large (increase TRF, TGRР, decreased ADR and medium (decreased Т1, Т2 arteries of the brain, decreased tone of the small arteries. Paravertebral myorelaxation of weightlifters caused them changes in the form of increasing tone of the great vessels (increase Т3, decreased tone of large and medium-sized arteries of the brain (increase АDR, Т2, increasing the tone of the small arteries (increase АI, DI. Reliable changes in cerebral hemodynamics have not been established at football players. Conclusions: The obtained data indicate that there are different mechanisms of adaptation in the brain blood vessels under conditions of the paravertebral miorelaxation. These differences are predetermined by two main factors: the functional state of the cardiovascular system in general and the functional states of the system of regulation of cerebral hemodynamics.

  6. Cerebral hypoxia

    Science.gov (United States)

    ... the veins ( deep vein thrombosis ) Lung infections (pneumonia) Malnutrition When to Contact a Medical Professional Cerebral hypoxia ... References Bernat JL. Coma, vegetative state, and brain death. In: Goldman L, Schafer AI, eds. Goldman's Cecil ...

  7. Cerebral Palsy (For Parents)

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy Cerebral Palsy KidsHealth > For Parents > Cerebral Palsy Print A A ... kids who are living with the condition. About Cerebral Palsy Cerebral palsy is one of the most common ...

  8. Características generales de 29 pacientes con vasculitis de pequeños vasos General characteristics of 29 patients with small vessel vasculitis

    Directory of Open Access Journals (Sweden)

    Nicolás Di Benedetto

    2010-04-01

    Full Text Available El objetivo de esta serie fue describir las características generales y manifestaciones clínicas de pacientes con vasculitis de pequeños vasos que concurrieron al servicio de autoinmunidad de un hospital de la comunidad y compararlas con la literatura. Se revisaron de manera retrospectiva las historias clínicas archivadas bajo el rótulo de vasculitis en un período de 16 años. Se seleccionaron aquellos pacientes que cumplieran criterios diagnósticos de vasculitis de pequeños vasos. Se extrajeron los datos de interés y se constató la supervivencia mediante contacto telefónico. Posteriormente se realizó una búsqueda bibliográfica y se compararon los resultados. Se incluyeron 13 pacientes con granulomatosis de Wegener, 6 con síndrome de Churg Strauss y 10 con poliangeítis microscópica. El 55% (16 fueron menores de 55 años al diagnóstico y hubo predominio del sexo femenino (2.6:1. La demora diagnóstica fue mayor a un año en el 46% de los casos. Los sistemas más frecuentemente afectados fueron respiratorio y otorrinolaringológico. El 79% presentó anticuerpos anti-citoplasma de neutrófilos (ANCA positivos. La mortalidad fue del 24% (7/29. Al comparar las características de los pacientes incluidos en esta serie con lo descripto en la literatura, se hallaron diferencias en cuanto a la forma de presentación, sistemas comprometidos y porcentaje de pacientes ANCA positivos; además se observó que el resultado negativo de este marcador parece asociarse con mayor demora diagnóstica y en consecuencia peor pronóstico, lo que remarca su importancia como herramienta adicional no invasiva al momento del diagnóstico.The objective of this series was to describe the general characteristics and clinical manifestations of patients with small vessel vasculitis who were assisted in the autoimmunity department of a community public hospital and to compare the results with the literature. Clinical records under the label of vasculitis in a

  9. Cilostazol reduces blood brain barrier dysfunction, white matter lesion formation and motor deficits following chronic cerebral hypoperfusion.

    Science.gov (United States)

    Edrissi, Hamidreza; Schock, Sarah C; Cadonic, Robert; Hakim, Antoine M; Thompson, Charlie S

    2016-09-01

    Cerebral small vessel disease (CSVD) is a pathological process leading to lacunar infarcts, leukoaraiosis and cerebral microbleeds. Dysfunction of the blood brain barrier (BBB) has been proposed as a mechanism in the progression cerebral small vessel disease. A rodent model commonly used to study some aspects of CSVD is bilateral common carotid artery occlusion (BCCAO) in the rat. In the present study it was determined that gait impairment, as determined by a tapered beam test, and BBB permeability increased following BCCAO. Cilostazol, a type III phosphodiesterase inhibitor, has been shown to have anti-apoptotic effects and prevent white matter vacuolation and rarefaction induced by BCCAO in rats. In this study the protective effect of cilostazol administration on the increase BBB permeability following BCCAO was determined as well as the effect on plasma levels of circulating microparticles (MPs), cerebral white matter rarefaction, glial activation and gait disturbance. The effect of cilostazol on in vitro endothelial barriers was also evaluated. Cilostazol treatment improved BBB permeability and reduced gait disturbance, visual impairment and microglial activation in optic tract following BCCAO in vivo. It also reduced the degree of cell death and the reduction in trans-endothelial electrical resistance (TEER) in artificial endothelial barriers in vitro induced by MP treatment of in vitro barriers. PMID:27350079

  10. An automated vessel segmentation of retinal images using multiscale vesselness

    International Nuclear Information System (INIS)

    The ocular fundus image can provide information on pathological changes caused by local ocular diseases and early signs of certain systemic diseases, such as diabetes and hypertension. Automated analysis and interpretation of fundus images has become a necessary and important diagnostic procedure in ophthalmology. The extraction of blood vessels from retinal images is an important and challenging task in medical analysis and diagnosis. In this paper, we introduce an implementation of the anisotropic diffusion which allows reducing the noise and better preserving small structures like vessels in 2D images. A vessel detection filter, based on a multi-scale vesselness function, is then applied to enhance vascular structures.

  11. Chronic kidney disease, 24-h blood pressure and small vessel diseases are independently associated with cognitive impairment in lacunar infarct patients

    International Nuclear Information System (INIS)

    Although the relationships between chronic kidney disease (CKD) and cognitive impairment (CI) have been highlighted, the etiology of CI in CKD remains uncertain. Subjects comprised 224 consecutive patients with symptomatic lacunar infarction who underwent magnetic resonance imaging and ambulatory blood pressure monitoring (ABPM). Diurnal blood pressure (BP) patterns were categorized into three groups: dippers, non-dippers and risers. Lacunar infarcts (LIs), including both symptomatic and silent and diffuse white matter lesions (WMLs), were graded into three grades according to their degree. The results of kidney function were evaluated using estimated glomerular filtration rate (eGFR), categorized into three groups: stage 1, >60; stage 2, 30-60; and stage 3, -1 per 1.73 m2. There were 44 patients with CI. Confluent WMLs, including WML 2 and WML 3, were found in 36 patients (81.8%), and multiple lacunae including LI 2 and LI 3 were found in 30 patients (68.1%) with CI. Age >75 years (odds ratio (OR), 5.5; P-1 per 1.73 m2 (OR, 2.9; P-1 per 1.73 m2 (OR, 23.8; P75 years (OR, 4.1; P-1 per 1.73 m2 (OR, 3.7; P-1 per 1.73 m2 (OR, 8.7; P<0.05) were independently associated with WML grade 3. Extensive small vessel diseases, CKD and non-dipping status were independently associated with CI. CKD appears to mainly contribute to vascular CI, whereas possibilities of overlapping with other mechanisms such as degenerative CI cannot be excluded. Strict night time BP control and renoprotective treatment may be warranted to prevent CI. (author)

  12. A clinical case of a patient with probable cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL from Chuvashia

    Directory of Open Access Journals (Sweden)

    Tatiana Vladimirovna Mokina

    2015-10-01

    Full Text Available Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL syndrome is a congenital small-vessel disease running with recurrent lacunar infarcts and leading to gradually progressive subcortical, pseudobulbar, and cerebellar syndromes and dementia. Neuroimaging reveal multiple lacunar infarcts in the basal ganglia, thalamus, pons Varolii, and cerebral hemispheric white matter, as well as cerebral atrophy. The specific feature of the disease is white matter lesion adjacent to the temporal horns of the lateral ventricles and to the external capsules. The paper describes a patient with CADASIL syndrome. The latter runs a progressive course and includes the following neurological disorders: cognitive, pyramidal, extrapyramidal, and axial ones. This clinical case was differentially diagnosed with multiple sclerosis, including with consideration for neuroimaging findings. The CADASIL syndrome is a rare potentially menacing neurological condition that is observed in young patients and requires a detailed examination using current diagnostic techniques.

  13. Regulation of the cerebral circulation: bedside assessment and clinical implications

    OpenAIRE

    Donnelly, Joseph; Budohoski, Karol P; Smielewski, Peter; Czosnyka, Marek

    2016-01-01

    Regulation of the cerebral circulation relies on the complex interplay between cardiovascular, respiratory, and neural physiology. In health, these physiologic systems act to maintain an adequate cerebral blood flow (CBF) through modulation of hydrodynamic parameters; the resistance of cerebral vessels, and the arterial, intracranial, and venous pressures. In critical illness, however, one or more of these parameters can be compromised, raising the possibility of disturbed CBF regulation and ...

  14. 脑安胶囊治疗高血压脑血管功能异常临床分析%Clinical analysis of cerebral blood vessel dysfunction in patients with hypertension

    Institute of Scientific and Technical Information of China (English)

    朱红潮

    2015-01-01

    目的:观察脑安胶囊治疗高血压脑血管功能异常临床效果.方法:选择我院于2013年7月至2014年7月期间收治的60例高血压脑血管功能异常患者,随机分成两组,每组各30例,对照组的高血压脑血管功能异常患者给予一般干预方法治疗,观察组的高血压脑血管功能异常患者服用脑安胶囊治疗.结果:观察组高血压脑血管功能异常患者治疗后的脑血管功能评分显著优于对照组(P<0.05).结论:脑安胶囊治疗高血压脑血管功能异常效果明显,值得临床推广.%Objective To observe the clinical effect of the treatment of hypertensive cerebral vascular dysfunction by. Give general intervention treatmentMethods in our hospital from July 2013 to 2014 July admitted during the period of 60 cases of hypertensive cerebral vascular function in patients with abnormal were randomly divided into two groups, 30 cases in each group. The control group of hypertensive cerebral vascular function in patients with abnormal, the observation group of hypertensive cerebral blood tube dysfunction in patients taking Naoan capsule in the treatment of.Results after the observation group of hypertensive cerebrovascular function treatment for patients with abnormal cerebrovascular function score was significantly better than the control group (P< 0.05).Conclusion the therapeutic effect of brain an Capsule on hypertensive cerebral vascular dysfunction is obvious, which is worthy of clinical application.

  15. Tuberculoma cerebral

    OpenAIRE

    BARROSO ELIZABETH CLARA; OLIVEIRA TÂNIA REGINA BRÍGIDO DE; AMARAL ANA MARIA DANTAS DO; PINHEIRO VALÉRIA GÓES FERREIRA; SOUSA ANA LÚCIA DE OLIVEIRA

    2002-01-01

    Relata-se o caso de paciente com crises convulsivas de início recente. A tomografia computadorizada cerebral evidenciou imagem sugestiva de lesão expansiva metastática frontoparietal direita. A investigação de tumor primário ou outra doença foi negativa e o exame histopatológico do tecido cerebral diagnosticou tuberculoma. As convulsões foram controladas com a associação de hidantoína 300mg/dia ao esquema específico, utilizado por 18 meses. A tuberculose do sistema nervoso central representa ...

  16. Vessel collisions with small cetaceans worldwide and with large whales in the Southern Hemisphere: building a standardized database. Scientific Committee document SC/58/BC6, International Whaling Commission, May-June 2006, St.Kitts

    OpenAIRE

    Van Waerebeek, K.; Baker, A.N.; Félix, F; Gedamke, J.; Iñiguez, M.; Sanino, G.P.; Secchi, E.; Sutaria, D.; van Helden, A.; Y Wang

    2006-01-01

    We compiled and reviewed 248 cases of reported vessel collisions with small cetaceans worldwide and with large cetaceans in the Southern Hemisphere. Difficulties were encountered with the comparison of highly variable data in terms of quality (evidence), sources, detail and degree of authentication. It is recommended that wide agreement be reached on a minimum dataset template. We propose 25 standardized parameters, including an essential ‘probability tag’ (confirmed, probable, possible and i...

  17. Stone vessels

    Czech Academy of Sciences Publication Activity Database

    Maříková Vlčková, Petra

    Prague : Charles University in Prague, 2010 - (Bárta, M.; Coppens, F.; Vymazalová, H.), s. 108-149 ISBN 978-80-7308-325-0 Institutional research plan: CEZ:AV0Z80020508 Keywords : stone vessels * Abusir South * Early Dynastic period * Old Kingdom * non-royal funerary architecture Subject RIV: AC - Archeology, Anthropology, Ethnology

  18. Comparative analysis of ECGs in navy personnel onboard large and small vessels during prolonged deployment at sea%海军护航不同舰艇官兵的心电图对比分析

    Institute of Scientific and Technical Information of China (English)

    杨翅; 蒋建华; 柳兵; 陈文; 彭焕亭

    2015-01-01

    目的:观察海军大、小不同类型舰艇亚丁湾护航返回官兵心电图特点。方法对赴亚丁湾海域护航返回的某补给舰(简称大舰组)140名官兵、某护卫舰(简称小舰组)79名官兵,分别在2艘舰艇返回靠泊的当天,行常规体表12导联心电图检测,比较心电图异常及心率、各波间期的变化情况。结果小舰组官兵室性早搏发生率高于大舰组官兵,差异有统计学意义(P<0.05);心率、左心室高电压、ST-T改变、早期复极、间歇性Ⅰ度或Ⅱ度Ⅰ型房室传导阻滞及各波形的间期差异均无统计学意义(P>0.05)。结论小舰官兵心律失常发生率高于大舰官兵,可能与小舰官兵自主神经功能失衡程度高,造成交感神经兴奋性增高有关。%Objective To observe the change features of ECG in navy personnel onboard large and small vessels after they re -turn from prolonged deployment to the Gulf of Aden .Methods One hundred and forty navy personnel onboard the auxiliary ship ( sim-ply designated as the large vessel ) and 79 people onboard the escort ( simply called the small vessel ) respectively received routine body surface 12-lead ECG detection , on the day they returned to the homeport , following prolonged deployment at sea .Abnormality in ECG and changes in heart rate and wave intervals were compared between the 2 ship crews.Results The incidence of premature ventricular contraction for the afloat personnel onboard the small vessel was higher than that for those onboard the large vessel (P0.05).Conclusion The incidence of arrhythmia for the afloat personnel onboard small vessel was evidently higher than that for the afloat personnel onboard the large ves -sel, which might be related with autonomic nervous system dysfunction and increased sympathetic nerve excitability .

  19. Effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats

    Institute of Scientific and Technical Information of China (English)

    Zuoli Xia; Baoling Sun; Mingfeng Yang; Dongmei Hu; Tong Zhao; Jingzhong Niu

    2006-01-01

    BACKGROUND: It has been shown that although brain does not contain lining endothelial lymphatic vessel,it has lymphatic drain.Anterior lymphatic vessel in brain tissue plays a key role in introducing brain interstitial fluid to lymphatic system;however,the significance of lymphatic drain and the affect on cerebral edema remains unclear.OBJECTIVE: To investigate the effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats.DESIGN: Randomized controlled animal study.SETTING: Institute of Cerebral Microcirulation of Taishan Medical College and Department of Neurology of Affiliated Hospital.MATERIALS:A total of 63 healthy adult male Wistar rats weighing 300-350 g were selected in this study.Forty-seven rats were used for the morphological observation induced by lymphatic drain and randomly divided into three groups:general observation group(n=12),light microscopic observation group(n=21)and electronic microscopic observation group(n=14).The rats in each group were divided into cerebral lymphatic block subgroup and sham-operation control subgroup.Sixteen rats were divided into cerebral the effect of cerebral lymphatic block on cortical evoked potential,in which the animals were randomly divided into sham-operation group(n=6)and cerebral lymphatic block group(n=10).METHODS:The experiment was carried out in the Institute of Cerebral Microcirculation of Taishan Medical College from January to August 2003.Rats in cerebral lymphatic block group were anesthetized and separated bilateral superficial and deep cervical lymph nodes under sterile condition. Superior and inferior boarders of lymph nodes were ligated the inputting and outputting channels, respectively, and then lymph node was removed so as to establish cerebral lymphatic drain disorder models. Rats in sham-operation control group were not ligated the lymphatic vessel and removed lymph nodes.and other operations were as the same as those in cerebral lymphatic block group

  20. 46 CFR 177.330 - Sailing vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Sailing vessels. 177.330 Section 177.330 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) CONSTRUCTION AND ARRANGEMENT Hull Structure § 177.330 Sailing vessels. The design, materials, and...

  1. Recurrent cerebral thrombosis

    International Nuclear Information System (INIS)

    Neuroradiological techniques were used to elucidate pathophysiology of recurrent cerebral thrombosis. Twenty-two patients with cerebral thrombosis who suffered a second attack under stable conditions more than 22 days after the initial stroke were studied. Hypertension, diabetes mellitus, and hypercholesterolemia were also seen in 20, 8, and 12 patients, respectively. The patients were divided into three groups according to their symptoms: (I) symptoms differed between the first and second strokes (n=12); (II) initial symptoms were suddenly deteriorated (n=6); and (III) symptoms occurring in groups I and II were seen (n=4). In group I, contralateral hemiparesis or suprabulbar palsy was often associated with the initial hemiparesis. The time of recurrent stroke varied from 4 months to 9 years. CT and MRI showed not only lacunae in both hemispheres, but also deep white-matter ischemia of the centrum semi-ovale. In group II, hemiparesis or visual field defect was deteriorated early after the initial stroke. In addition, neuroimaging revealed that infarction in the posterior cerebral artery was progressed on the contralateral side, or that white matter lesion in the middle artery was enlarged in spite of small lesion in the left cerebral hemisphere. All patients in group III had deterioration of right hemiparesis associated with aphasia. CT, MRI, SPECT, and angiography indicated deep white-matter ischemia caused by main trunk lesions in the left hemisphere. Group III seemed to be equivalent to group II, except for laterality of the lesion. Neuroradiological assessment of the initial stroke may help to predict the mode of recurrence, although pathophysiology of cerebral thrombosis is complicated and varies from patient to patient. (N.K.)

  2. Renovascular hypertension causes cerebral vascular remodeling

    Institute of Scientific and Technical Information of China (English)

    Yamei Tang; Xiangpen Li; Yi Li; Qingyu Shen; Xiaoming Rong; Ruxun Huang; Ying Peng

    2011-01-01

    Renovascular hypertensive rats (RHRs) were developed using the 2-kidney, 2-clip method. All RHRs at 10 weeks displayed high permeability of the cerebral surface blood vessels. Vascular casts of the RHRs showed that the vascular network was sparse. The arterioles of the RHRs at 10 weeks had smaller lumen diameters, but thicker vessel walls with hyalinosis formation compared with control animals. The endothelial cell membrane appeared damaged, and microthrombus formed. After ischemia, the infarction size was larger in RHRs than in control animals. These results suggest that cerebral arterioles in RHRs underwent structural remodeling. High blood pressure may aggravate the severity of brain injury in cerebral ischemia and affect the recovery of ischemia.

  3. Reactor pressure vessel steels

    International Nuclear Information System (INIS)

    Research and development activities related to reactor pressure vessel steels during 1997 are reported. The objectives of activities of the Belgian Nuclear Research Centre SCK/CEN in this domain are: (1) to develop enhanced surveillance concepts by applying micromechanics and fracture-toughness tests to small specimens, and by performing damage modelling and microstructure characterization; (2) to demonstrate a methodology on a broad database; (3) to achieve regulatory acceptance and industrial use

  4. Etiologic evaluation of periventricular hyperintensity in MR images of first-ever cerebral thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, Toshihiko; Enomoto, Mutsurou; Ogawa, Kimikazu; Yanagawa, Kiyotaka; Takasaki, Masaru [Tokyo Medical Coll. (Japan)

    1995-02-01

    To clarify the etiology of periventricular hyperintensity (PVH) seen on magnetic resonance (MR) images (especially on T2-weighted images), PVH was investigated in relation to causative lesions, angiographic findings, and risk factors for cerebrovascular accidents. The subjects were 103 patients with first-ever cerebral thrombosis (thrombosis group). Age-matched 37 patients with hypertension or diabetes mellitus (risk group) and 78 other patients with neither stroke nor any risk factor served as controls. MR imaging and angiography were undertaken within 3 months after the onset of stroke. Causative lesions were confined to the cerebral cortex (CR type, n=25), centrum semiovale (CS type, n=10), internal capsule/corona radiata (IC/CR type, n=46), and brainstem/cerebellum (BS type, n=22). PVH was classified into none, rims/caps, patchy, and diffuse. Patchy and diffuse types were significantly more common in the thrombosis group and the risk group of hypertensive patients than the other control patients. Diffuse type PVH coexisted with stenosed major cerebral artery and CS type infarction. In contrast, patchy PVH was closely correlated with IC/CR infarction caused by lesions of the perforating artery. These findings suggest that hemodynamic changes caused by large vessel diseases may result in diffuse PVH, while patchy PVH was confluent with multiple lesions induced by small vessel diseases. (N.K.).

  5. Etiologic evaluation of periventricular hyperintensity in MR images of first-ever cerebral thrombosis

    International Nuclear Information System (INIS)

    To clarify the etiology of periventricular hyperintensity (PVH) seen on magnetic resonance (MR) images (especially on T2-weighted images), PVH was investigated in relation to causative lesions, angiographic findings, and risk factors for cerebrovascular accidents. The subjects were 103 patients with first-ever cerebral thrombosis (thrombosis group). Age-matched 37 patients with hypertension or diabetes mellitus (risk group) and 78 other patients with neither stroke nor any risk factor served as controls. MR imaging and angiography were undertaken within 3 months after the onset of stroke. Causative lesions were confined to the cerebral cortex (CR type, n=25), centrum semiovale (CS type, n=10), internal capsule/corona radiata (IC/CR type, n=46), and brainstem/cerebellum (BS type, n=22). PVH was classified into none, rims/caps, patchy, and diffuse. Patchy and diffuse types were significantly more common in the thrombosis group and the risk group of hypertensive patients than the other control patients. Diffuse type PVH coexisted with stenosed major cerebral artery and CS type infarction. In contrast, patchy PVH was closely correlated with IC/CR infarction caused by lesions of the perforating artery. These findings suggest that hemodynamic changes caused by large vessel diseases may result in diffuse PVH, while patchy PVH was confluent with multiple lesions induced by small vessel diseases. (N.K.)

  6. Primary angiitis of the central nervous system with diffuse cerebral mass effect and giant cells.

    LENUS (Irish Health Repository)

    Kinsella, J A

    2012-02-01

    Primary angiitis of the central nervous system (PACNS), also called primary CNS vasculitis, is an idiopathic inflammatory condition affecting only intracranial and spinal cord vessels, particularly medium-sized and smaller arteries and arterioles. Angiography and histopathology typically do not reveal evidence of systemic vasculitis.(1,2) Histopathology usually reveals granulomatous inflammation affecting arterioles and small arteries of the parenchyma and\\/or leptomeninges, similar to that seen in Takayasu\\'s or giant cell arteritis.(1-3) We report a patient with biopsy-proven PACNS with giant cells and cerebral mass effect on MRI. Magnetic resonance angiography and cerebral angiography appeared normal and there was no evidence of extracranial vasculitis.

  7. Employees with Cerebral Palsy

    Science.gov (United States)

    ... Resources Home | Accommodation and Compliance Series: Employees with Cerebral Palsy (CP) By Eddie Whidden, MA Preface Introduction Information ... SOAR) at http://AskJAN.org/soar. Information about Cerebral Palsy (CP) What is CP? Cerebral palsy is a ...

  8. Current meter components and other data from XCP casts from VARIOUS SMALL VESSELS and other platforms from the North Atlantic Ocean as part of the OCEAN DUMPING and other projects from 01 December 1990 to 01 June 1991 (NODC Accession 9300076)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter components and other data were collected from XCP casts from VARIOUS SMALL VESSELS and other platforms in the North Atlantic Ocean. Data were...

  9. CBF and CMRo/sub 2/ during craniotomy for small supratentorial cerebral tumours in enflurane anaesthesia. A dose-response study

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, J.B.; Cold, G.E.; Eriksen, H.O.; Eskesen, V.; Blatt-Lyon, B.

    1986-01-01

    In 14 patients with supratentorial cerebral tumors with midline shift less than or equal to 10 mm, cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRo/sub 2/) were measured twice on the contralateral side of the craniotomy, using a modification of the Kety and Schmidt method. For induction of anaesthesia, thiopental, fentanyl and pancuronium were used. The anaesthesia was maintained with enflurane 1% in nitrous oxide 67%. Moderate hypocapnia to a level averaging 4.3 kPa was achieved. The patients were divided into two groups. In group 1 (n=7), 1% enflurane was used throughout the anaesthesia, and CBF and CMRo/sub 2/ measured about 70 min after induction averaged 30.1 ml 100 g/sup -1/ min/sub -1/ and 1.98 ml O/sub 2/ 100 g/sup -1/ min/sup -1/, respectively. During the second CBF study 1 h later, CBF and CMRo/sub 2/ were unchanged (P>0.05). In group 2 (n=7), the inspiratory enflurane concentration was increased from 1 to 2% after the first CBF measurement. In this group a significant decrease in CMRo/sub 2/ was observed, while CBF was unchanged. In six patients EEG was recorded simultaneously with the CBF measurements. In patients subjected to increasing enflurane concentration (Group 2), a suppression in the EEG activity was observed without spike waves. It is concluded that enflurane induces a dose-related decrease in CMRo/sub 2/ and suppression in the EEG activity, whereas CBF was unchanged.

  10. Cerebral palsy

    International Nuclear Information System (INIS)

    This paper reviews cranial MR findings in patients with cerebral palsy (CP) to clarify and categorize this disorder. The MR images of 40 patients with clinical CP were retrospectively reviewed. All patients suffered either varying spastic plegias, hypotonicity, or choreoathetosis. Concomitantly, the patients suffered from static encephalopathy, developmental delay, and/or microcephaly. Twenty-four patients were born at or near term, 10 were premature, and incomplete birth histories were available in six. The MR images revealed mild to severe degrees of white matter damage in 24 patients (12 term, nine premature, three unknown)

  11. Effects of Electroacupuncture plus Intra-carotid Drug Injection on Rheoencephalogram in Patients with Cerebral Infarction

    Institute of Scientific and Technical Information of China (English)

    李江明; 胡永均; 童利民; 王大军; 张道敬

    2004-01-01

    Purpose: To investigate the mechanism of electroacupuncture (EA) plus intra-carotid drug injection for treating cerebral infarction. Methods: Rheoencephalogram was recorded with a RG-2B type of bridge rheoencephalograph and findings were compared before and after the treatment. Results: After the treatment, the prolonged rising time was shortened, and the decreased amplitude obviously elevated. Conclusion: The therapy can dilate cerebral blood vessels, increase the cerebral blood flow, and improve the elasticity of cerebral blood vessels, leading to sufficient blood and oxygen supply in the ischemic brain tissues and to restoration of their functions.

  12. Cerebral malaria.

    Science.gov (United States)

    Postels, Douglas G; Birbeck, Gretchen L

    2013-01-01

    Malaria, the most significant parasitic disease of man, kills approximately one million people per year. Half of these deaths occur in those with cerebral malaria (CM). The World Health Organization (WHO) defines CM as an otherwise unexplained coma in a patient with malarial parasitemia. Worldwide, CM occurs primarily in African children and Asian adults, with the vast majority (greater than 90%) of cases occurring in children 5 years old or younger in sub-Saharan Africa. The pathophysiology of the disease is complex and involves infected erythrocyte sequestration, cerebral inflammation, and breakdown of the blood-brain barrier. A recently characterized malarial retinopathy is visual evidence of Plasmodium falciparum's pathophysiological processes occurring in the affected patient. Treatment consists of supportive care and antimalarial administration. Thus far, adjuvant therapies have not been shown to improve mortality rates or neurological outcomes in children with CM. For those who survive CM, residual neurological abnormalities are common. Epilepsy, cognitive impairment, behavioral disorders, and gross neurological deficits which include motor, sensory, and language impairments are frequent sequelae. Primary prevention strategies, including bed nets, vaccine development, and chemoprophylaxis, are in varied states of development and implementation. Continuing efforts to find successful primary prevention options and strategies to decrease neurological sequelae are needed. PMID:23829902

  13. Functional stability of cerebral circulatory system

    Science.gov (United States)

    Moskalenko, Y. Y.

    1980-01-01

    The functional stability of the cerebral circulation system seems to be based on the active mechanisms and on those stemming from specific of the biophysical structure of the system under study. This latter parameter has some relevant criteria for its quantitative estimation. The data obtained suggest that the essential part of the mechanism for active responses of cerebral vessels which maintains the functional stability of this portion of the vascular system, consists of a neurogenic component involving central nervous structures localized, for instance, in the medulla oblongata.

  14. Follow-up CT of hemorrhagic cerebral infarction

    International Nuclear Information System (INIS)

    The computed tomography (CT) findings in cases of hemorrhagic cerebral infarction were divided into the following two different patterns: (1) The precontrast scan showed small high-density spots, mainly at the cortico-subcortical junctions. These appeared to represent a small amount of hemorrhage. The contrast enhancements were remarkable around these high-density areas as observed by the plain CT. (2) The precontrast scan showed only low-density areas, but the contrast scan showed an enhancement at the border zone of the gray and white junction, similar to those observed in Type 1 CT. Three (20%) of the 15 patients presented Type 1, and 12 patients (80%), Type 2. In the cases of Type 1, a positive CE was seen within a few days after the insult. This CE demonstrated the disturbance of the blood-brain barrier (B B B) during the stage of vasogenic edema. In the cases of Type 2, the positive CE was further divided into two subtypes: the early stage (2 to 3 weeks) and the late stage (4 weeks) after the stroke. The positive CE at the early stage, might be explainable to a significant extent by an extravasation of the contrast medium resulting from permeability changes in the vessels located in the boundary zones of the gray and white matter. On the contrary, the CE enhancement observed in the late stage might result chiefly from newly formed vessels with a defective BBB in and around the infarcted area. (author)

  15. Effects of JPEG data compression on magnetic resonance imaging evaluation of small vessels ischemic lesions of the brain; Efeitos da compressao de dados JPEG na avaliacao de lesoes vasculares cerebrais isquemicas de pequenos vasos em ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Kuriki, Paulo Eduardo de Aguiar; Abdala, Nitamar; Nogueira, Roberto Gomes; Carrete Junior, Henrique; Szejnfeld, Jacob [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Diagnostico por Imagem]. E-mail: paulokuriki@gmail.com

    2006-01-15

    Objective: to establish the maximum achievable JPEG compression ratio without affecting quantitative and qualitative magnetic resonance imaging analysis of ischemic lesion in small vessels of the brain. Material and method: fifteen DICOM images were converted to JPEG with a compression ratio of 1:10 to 1:60 and were assessed together with the original images by three neuro radiologists. The number, morphology and signal intensity of the lesions were analyzed. Results: lesions were properly identified up to a 1:30 ratio. More lesions were identified with a 1:10 ratio then in the original images. Morphology and edges were properly evaluated up toa 1:40 ratio. Compression did not affect signal. Conclusion: small lesions were identified ( < 2 mm ) and in all compression ratios the JPEG algorithm generated image noise that misled observers to identify more lesions in JPEG images then in DICOM images, thus generating false-positive results.(author)

  16. Amylin: Localization, Effects on Cerebral Arteries and on Local Cerebral Blood Flow in the Cat

    Directory of Open Access Journals (Sweden)

    Lars Edvinsson

    2001-01-01

    Full Text Available Amylin and adrenomedullin are two peptides structurally related to calcitonin gene-related peptide (CGRP. We studied the occurrence of amylin in trigeminal ganglia and cerebral blood vessels of the cat with immunocytochemistry and evaluated the role of amylin and adrenomedullin in the cerebral circulation by in vitro and in vivo pharmacology. Immunocytochemistry revealed that numerous nerve cell bodies in the trigeminal ganglion contained CGRP immunoreactivity (-ir; some of these also expressed amylin-ir but none adrenomedullin-ir. There were numerous nerve fibres surrounding cerebral blood vessels that contained CGRP-ir. Occasional fibres contained amylin-ir while we observed no adrenomedullin-ir in the vessel walls. With RT-PCR and Real-Time�PCR we revealed the presence of mRNA for calcitonin receptor-like receptor (CLRL and receptor-activity-modifying proteins (RAMPs in cat cerebral arteries. In vitro studies revealed that amylin, adrenomedullin, and CGRP relaxed ring segments of the cat middle cerebral artery. CGRP and amylin caused concentration-dependent relaxations at low concentrations of PGF2a-precontracted segment (with or without endothelium whereas only at high concentration did adrenomedullin cause relaxation. CGRP8-37 blocked the CGRP and amylin induced relaxations in a parallel fashion. In vivo studies of amylin, adrenomedullin, and CGRP showed a brisk reproducible increase in local cerebral blood flow as examined using laser Doppler flowmetry applied to the cerebral cortex of the a-chloralose�anesthetized cat. The responses to amylin and CGRP were blocked by CGRP8-37. The studies suggest that there is a functional sub-set of amylin-containing trigeminal neurons which probably act via CGRP receptors.

  17. Cerebral cysticercosis

    International Nuclear Information System (INIS)

    Two cases of histologically proven cerebral cysticercosis are presented. In both cases subcutaneous tissue nodules, a rare feature, were present. Several disease patterns are apparent - meningeal, parenchymatous and ventricular, spinal cord lesions and mixed patterns. Epilepsy is by far the major presenting symptom of cysticercosis, which in turn plays a significant role in the causation of adult-onset epilepsy in Blacks. Despite its drawbacks, the haemag-glutination inhibition test remains the most satisfactory serological method at present available for the diagnosis of cysticercosis; it is positive in up to 85% of cases of proven cysticercosis. With the advent of computed tomography many cases of unsuspected cysticercosis (symptomatic or asymptomatic) are being discovered

  18. Epidemiological study of 183 patients with spontaneous rupture of cerebral aneurysm

    International Nuclear Information System (INIS)

    Cerebral vessels aneurysms represent a significant part of the cerebral vessels pathology. There is no extensive study on that in Bulgaria. We present a study of 183 patients with spontaneous rupture of cerebral aneurysm, diagnosed and treated in UMHATEM ‘Pirogov’, Sofia. We used clinical methods - data from subject history, analysis of the accompanying documentation, subject medical chart; imaging-diagnostics methods - CT, DSA and MRI; and statistical methods. A total of 183 patients with ruptured intracranial aneurysms were studied. 65% were females and 35% were men.The ration female/male is 1.86, The mean age of all patients is 53.1 ±10.1 years. The highest incidence of ruptured aneurysms is seen in the age group 50 to 59 years. Aneurysms of a. cerebri media and a. communicants anterior are the most frequent (63.4% in total); while the lest are those of a basilaris (4.9%). 88.5% of the aneurysms in the studied group are small, 9.8% are large and 1.6% are giant. Intracranial hematomas are seen in 13.1% of the patients with ruptured aneurysms. Most frequently hematomas are connected with a. cerebri media and a.communicants anterior (87.5% in total). Patients with multiple aneurysms are 11.5% in total, 85.7% of them with an aneurysm of a.cerebri media. The incidence of ruptured cerebral aneurysms is higher amongst female. Frequency in the fifth decade of life is the highest. Most often seen are the aneurysms of a. cerebri media and a. communicants anterior, and the least - those of a. basilaris. Intracranial hematomas most frequently are associated with ruptures of a. cerebri media and a. communicants anterior, in patients with multiple aneurysms the highest is the frequency of aneurysms of a. cerebri media. (authors)

  19. Angiographic Findings In Patients With Cerebral Aneurysm

    Directory of Open Access Journals (Sweden)

    Miri S M

    2004-09-01

    Full Text Available Background: This investigation was conducted in order to study angiographic findings in patients with cerebral aneurysm. Materials and Methods: The study conducted on 136 cases of ruptured cerebral aneurysms between 1995-2000 confirmed by means of 4-vessel cerebral angiography to get an insight to racial, geographic and environmental factors predisposing to the occurrence of subarachnoid hemorrhage and aneurysm formation. Results: The data analysis revealed the following results: 58% of the population comprised of male and 42% female with a mean age of 46 years. 89% of the aneurysms were found in the anterior circulation and 11% occurred in the posterior cerebral circulation. The most common site in both the sexes was the anterior communicating artery. 9.6% of the patients displayed two separate aneurysms. 5.2% of the aneurysms were found to be giant aneurysms and 3% of the patients had fusiform aneurysms. Conclusion: The low average age, a predilection in male population and the prevalence of aneurysms at carotid and middle cerebral artery bifurcation and the distal branches of anterior cerebral artery and a higher incidence of anterior communicating artery in women were the findings observed in this study.

  20. Pathogenesis of cerebral malaria

    International Nuclear Information System (INIS)

    Full text: Cerebral Malaria (CM) is the most severe complication of malaria and a major cause of death. The mechanisms underlying human CM pathogenesis might be due to mechanical cause, as demonstrated by cytoadherence of parasitised erythrocytes pRB, or to excessive cytokine production by the host in response to Plasmodium falciparum, or a combination of the two together with neuronal injury by malaria toxins. Antibody response, genetic traits and other factors have been proposed to explain why only some episodes have life-threatening complications. The microvascular endothelial cell is a major target of inflammatory cytokines overproduced in infectious diseases. Fatal CM is associated with widespread induction of endothelial activation markers, with significant higher levels of ICAM, VCAM and E-selectin expression on vessels in the brain. 199 patients were admitted at the hospital and were classified with malaria-based neurological disfunctions, such as acute psychosis, ataxia, hallucinations, fever and convulsions, prostration or coma. On a flow chart, 65 of those patients with the most acute syndromes mentioned above, were found to have negative BSN (blood slide), compared to 124 where the BSN showed to be positive. Identically to the 10 other patients from the severe form group, also presented positive BSN. The condition of some of these two subgroup patients (15), will later evolve into a more severe form with acute neurological disfunctions attributed to the cerebral malaria. The interesting aspect in regards to the 65 patients considered as having CM, upon severe manifestations of the disease, show no or little peripheral parasitemia. This fact confirms our experimental conclusion that, in the process of pRB adhesion to the microvessels of the brain, they are sequestered by monocytes and platelets, leading to vessel rupture. This fact could be an explanation of the lower % of circulating pRB and low peripheral parasitemia. There is a relationship between

  1. Vessel Activity Record

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Activity Record is a bi-weekly spreadsheet that shows the status of fishing vessels. It records whether fishing vessels are fishing without an observer...

  2. Vessel Operator System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operator cards are required for any operator of a charter/party boat and or a commercial vessel (including carrier and processor vessels) issued a vessel permit...

  3. JPDR vessel steel examination

    International Nuclear Information System (INIS)

    There is a need to validate the results of irradiation effects research by the examination of material taken directly from the wall of a pressure vessel which has been irradiated during normal service. This task has been included with the HSSI Program to provide just such an evaluation of material from the wall of the pressure vessel from the JPDR. The JPDR was a small BWR that began operation in 1963. It operated until 1976, accumulating ∼17,000 h of operation, of which a little over 14,000 h were with the original 45-MWTh core, and the remaining fraction, late in life, with an upgraded 90-MWTh core. The pressure vessel of the JPDR, fabricated from A 302, grade B, modified steel with an internal weld overlay cladding of 304 stainless steel, is approximately 2 m ID and 73 mm thick. It was fabricated from two shell halves joined by longitudinal seam welds located 180 degrees from each other. The rolling direction of the shell plates is parallel to the axis of the vessel. It operated at 273 degrees C and reached a maximum fluence of about 2.3 x 1018 n/cm2 (> 1 MeV). The impurity contents in the base metal are 0.10 to 0.11% Cu and 0.010 to 0.017% P with a nickel content of 0.63 to 0.65%. Impurity contents of the weld metal are 0.11 to 0.14% Cu and 0.025 to 0.039% P with a nickel content of 0.59%

  4. INFLUENCE OF DIFFERENT NEEDLE-RETAINING DURATION ON CEREBRAL HEMODYNAMICS OF CEREBRAL PARALYSIS CHILDREN

    Institute of Scientific and Technical Information of China (English)

    袁青; 王琴玉; 冯健强; 张壮涛; 陈雪云; 靳瑞

    2004-01-01

    Objective: To investigate the effects of different needle-retaining duration on cerebral hemodynamics in cerebral paralysis (CP) children.Methods: A total of 20 cases of CP children were subjected into this study.Changes of systolic peak value (Vs), blood flow velocity at the end-diastolic phase (Ved), mean velocity (Vm), pulsation index (PI) and resistance index (RI) of the cerebral hemodynamics before and after performing JIN's Three-Needling Therapy with the needles retained for 30 min (group A) and 5 min (group B) were observed by using transcranial Doppler ultrasonography (TCD).Results: After acupuncture, the blood flow in the middle cerebral artery (MCA), anterior cerebral artery (ACA) and posterior cerebral artery (PCA) was accelerated, and the resistance of blood vessels decreased.The effect of needle-retaining-30 min was better than that of needle-retaining-5 min.Conclusion: In treating cerebral paralysis by using JIN's Three-Needling Therapy, sufficient stimulation provided by needle remaining is an important factor for achieving satisfactory therapeutic effects.

  5. Advanced Imaging Modalities in the Detection of Cerebral Vasospasm

    OpenAIRE

    Mills, Jena N.; Vivek Mehta; Jonathan Russin; Amar, Arun P.; Anandh Rajamohan; William J. Mack

    2013-01-01

    The pathophysiology of cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH) is complex and is not entirely understood. Mechanistic insights have been gained through advances in the capabilities of diagnostic imaging. Core techniques have focused on the assessment of vessel caliber, tissue metabolism, and/or regional perfusion parameters. Advances in imaging have provided clinicians with a multifaceted approach to assist in the detection of cerebral vasospasm and the diagnosis...

  6. Pleuropulmonary blastoma with a large embolic cerebral infarct

    Energy Technology Data Exchange (ETDEWEB)

    Tan Kendrick, Anne P.A.; Krishnamurthy, Ganesh [Department of Diagnostic Imaging, Kandang Kerbau Women' s and Children' s Hospital (Singapore); Joseph, V.T. [Department of Paediatric Surgery, Kandang Kerbau Women' s and Children' s Hospital (Singapore)

    2003-07-01

    We report on a 3-year-old girl who developed a large embolic cerebral infarct 1 day after an uneventful thoracotomy to remove a large pleuropulmonary blastoma. The tumour had encased the heart and great vessels and ruptured into the left hemithorax. Pleuropulmonary blastoma is a rare, but unique, primary thoracic neoplasm in young children and, to our knowledge, the development of a secondary large embolic cerebral infarct is also uncommon and has not been reported in this tumour. (orig.)

  7. Cerebral angiographic findings in thromboangiitis obliterans

    Energy Technology Data Exchange (ETDEWEB)

    No, Young J.; Lee, Eun M.; Kim, Jong S. [University of Ulsan, Department of Neurology, Asan Medical Center, Song Pa, PO Pox 145, Seoul (Korea); Lee, Deok H. [University of Ulsan, Department of Neuroradiology, Asan Medical Center, Song Pa, PO Pox 145, Seoul (Korea)

    2005-12-01

    Transient ischemic attacks (TIAs) or ischemic stroke may complicate thromboangiitis obliterans (TAO). However, there has been debate regarding the mechanism of ischemic stroke in TAO. We report the case of a patient with TAO who developed repeated TIAs. An angiogram showed multiple alternative areas of arterial occlusions in the distal segments of both middle cerebral arteries. Extensive collateral vessels around the occluded segment were also observed, which resembled the ''tree root'' or ''corkscrew'' vessels described in the peripheral arteries in TAO. Our patient illustrates that cerebral manifestations of TAO may occur with vascular changes that are identical with those encountered in the limb arteries in TAO. (orig.)

  8. In depth pharmacological characterization of endothelin B receptors in the rat middle cerebral artery

    DEFF Research Database (Denmark)

    Szok, D; Hansen-Schwartz, J; Edvinsson, L

    2001-01-01

    middle cerebral artery were cannulated with micropipettes, pressurized and luminally perfused. Vessel diameters were evaluated using a microscope equipped with an imaging system. Both intra- and extraluminal applications of endothelin-1 produced constriction. Intraluminal administration of a selective...

  9. Comparison of Two Therapeutic Strategies in Patients With Non-squamous Non-small Cell Lung Cancer (NSCLC) With Asymptomatic Brain Metastases

    Science.gov (United States)

    2015-11-29

    Non-small Cell Lung Cancer Metastatic; Non Epidermoid; Non-small Cell Lung Cancer; Adenocarcinoma of Lung Metastatic to Brain; Cerebral Metastases; Cerebral Radiotherapy; Brain Radiotherapy; Bevacizumab

  10. Simplified techniques of cerebral angiography using a mobile X-ray unit and computed radiography

    International Nuclear Information System (INIS)

    Simplified techniques of cerebral angiography using a mobile X-ray unit and computed radiography (CR) are discussed. Computed radiography is a digital radiography system in which an imaging plate is used as an X-ray detector and a final image is displayed on the film. In the angiograms performed with CR, the spatial frequency components can be enhanced for the easy analysis of fine blood vessels. Computed radiography has an automatic sensitivity and a latitude-setting mechanism, thus serving as an 'automatic camera.' This mechanism is useful for radiography with a mobile X-ray unit in hospital wards, intensive care units, or operating rooms where the appropriate setting of exposure conditions is difficult. We applied this mechanism to direct percutaneous carotid angiography and intravenous digital subtraction angiography with a mobile X-ray unit. Direct percutaneous carotid angiography using CR and a mobile X-ray unit were taken after the manual injection of a small amount of a contrast material through a fine needle. We performed direct percutaneous carotid angiography with this method 68 times on 25 cases from August 1986 to December 1987. Of the 68 angiograms, 61 were evaluated as good, compared with conventional angiography. Though the remaining seven were evaluated as poor, they were still diagnostically effective. This method is found useful for carotid angiography in emergency rooms, intensive care units, or operating rooms. Cerebral venography using CR and a mobile X-ray unit was done after the manual injection of a contrast material through the bilateral cubital veins. The cerebral venous system could be visualized from 16 to 24 seconds after the beginning of the injection of the contrast material. We performed cerebral venography with this method 14 times on six cases. These venograms were better than conventional angiograms in all cases. This method may be useful in managing patients suffering from cerebral venous thrombosis. (J.P.N.)

  11. APOL1 renal-risk variants associate with reduced cerebral white matter lesion volume and increased gray matter volume.

    Science.gov (United States)

    Freedman, Barry I; Gadegbeku, Crystal A; Bryan, R Nick; Palmer, Nicholette D; Hicks, Pamela J; Ma, Lijun; Rocco, Michael V; Smith, S Carrie; Xu, Jianzhao; Whitlow, Christopher T; Wagner, Benjamin C; Langefeld, Carl D; Hawfield, Amret T; Bates, Jeffrey T; Lerner, Alan J; Raj, Dominic S; Sadaghiani, Mohammad S; Toto, Robert D; Wright, Jackson T; Bowden, Donald W; Williamson, Jeff D; Sink, Kaycee M; Maldjian, Joseph A; Pajewski, Nicholas M; Divers, Jasmin

    2016-08-01

    To assess apolipoprotein L1 gene (APOL1) renal-risk-variant effects on the brain, magnetic resonance imaging (MRI)-based cerebral volumes and cognitive function were assessed in 517 African American-Diabetes Heart Study (AA-DHS) Memory IN Diabetes (MIND) and 2568 hypertensive African American Systolic Blood Pressure Intervention Trial (SPRINT) participants without diabetes. Within these cohorts, 483 and 197 had cerebral MRI, respectively. AA-DHS participants were characterized as follows: 60.9% female, mean age of 58.6 years, diabetes duration 13.1 years, estimated glomerular filtration rate of 88.2 ml/min/1.73 m(2), and a median spot urine albumin to creatinine ratio of 10.0 mg/g. In additive genetic models adjusting for age, sex, ancestry, scanner, intracranial volume, body mass index, hemoglobin A1c, statins, nephropathy, smoking, hypertension, and cardiovascular disease, APOL1 renal-risk-variants were positively associated with gray matter volume (β = 3.4 × 10(-3)) and negatively associated with white matter lesion volume (β = -0.303) (an indicator of cerebral small vessel disease) and cerebrospinal fluid volume (β= -30707) (all significant), but not with white matter volume or cognitive function. Significant associations corresponding to adjusted effect sizes (β/SE) were observed with gray matter volume (0.16) and white matter lesion volume (-0.208), but not with cerebrospinal fluid volume (-0.251). Meta-analysis results with SPRINT Memory and Cognition in Decreased Hypertension (MIND) participants who had cerebral MRI were confirmatory. Thus, APOL1 renal-risk-variants are associated with larger gray matter volume and lower white matter lesion volume suggesting lower intracranial small vessel disease. PMID:27342958

  12. 46 CFR 119.330 - Pressure vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Pressure vessels. 119.330 Section 119.330 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE THAN 150 PASSENGERS OR WITH OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS MACHINERY INSTALLATION...

  13. Cocaine Constrictor Mechanisms of the Cerebral Vasculature.

    Science.gov (United States)

    Rapoport, Robert M; Yoon, SeongHun; Zuccarello, Mario

    2016-05-01

    Cocaine constriction of the cerebral vasculature is thought to contribute to the ischemia associated with cocaine use. However, the mechanisms whereby cocaine elicits relevant vasoconstriction remain elusive. Indeed, proposed intra- and intercellular mechanisms based on over 3 decades of ex vivo vascular studies are, for the most part, of questionable relevancy due to the generally low contractile efficacy of cocaine combined with the use of nonresistance-type vessels. Furthermore, the significance attached to mechanisms derived from in vivo animal studies may be limited by the inability to demonstrate cocaine-induced decreased cerebral blood flow, as observed in (awake) humans. Despite these apparent limitations, we surmise that the vasoconstriction relevant to cocaine-induced ischemia is elicited by inhibition of dilator and activation of constrictor pathways because of cocaine action on the neurovascular unit (neuron, astrocyte, and vessel) and on vessels outside the unit. Furthermore, previous cocaine exposure, that is, conditions present in human subjects, downregulates and sensitizes these dilator and constrictor pathways, respectively, thereby enhancing constriction to acute cocaine. Identification of specific intra- and intercellular mechanisms requires investigations in the isolated microvasculature and the neurovascular unit from species chronically exposed to cocaine and in which cocaine decreases cerebral blood flow. PMID:26771152

  14. United Cerebral Palsy

    Science.gov (United States)

    ... Voices of UCP blog for the latest updates. United Cerebral Palsy UCP educates, advocates and provides support ... Our Partners Merz Logo Sprint Relay Copyright © 2015 United Cerebral Palsy 1825 K Street NW Suite 600 ...

  15. Prevalence of cerebral and pulmonary thrombosis in patients with cyanotic congenital heart disease

    DEFF Research Database (Denmark)

    Jensen, A S; Idorn, L; Thomsen, C;

    2015-01-01

    BACKGROUND: Patients with cyanotic congenital heart disease (CCHD) have a high prevalence of thrombosis, the most frequently described locations being the cerebral and pulmonary vessels. The reported prevalence of both cerebral infarction and pulmonary thrombosis has been highly variable. The aim...

  16. Cerebral palsy and epilepsy

    OpenAIRE

    Knežević-Pogančev Marija

    2010-01-01

    Introduction. Cerebral palsy is the most common cause of physical disability in early childhood. Epilepsy is known to have a high association with cerebral palsy. All types of epileptic seizures can be seen in patients with cerebral palsy. Complex partial and secondary generalized ones are the most frequent seizure types. In persons with cerebral palsy and mental retardation, the diagnosis of epilepsy presents unique difficulties. Generally they are not able to describe the epileptic ev...

  17. Role of precoating in artificial vessel endothelialization

    Institute of Scientific and Technical Information of China (English)

    肖乐; 时德

    2004-01-01

    @@ As the progress of vascular surgery, artificial vessels have become the substitute for large and middle diameter vessels but have not for small diameter ones owing to thrombogenesis and occlusion within a short period of time after being applied.Artificial vessel endothelialization is one of the ideal methods to resolve such issue and has been improved continuously since Herring1 in 1978 put forward this term in the first time and utilized vascular endothelial cells (ECs) harvested from living animals to perform the test of artificial vessel endothelialization.

  18. Pathological review of late cerebral radionecrosis

    International Nuclear Information System (INIS)

    Late cerebral radionecrosis may be considered to be a specific chronic inflammatory response, although it is unknown whether the initial damage by brain irradiation is to an endothelial cell or a glial cell. I discuss the pathological specificity of late cerebral radionecrosis by studying the published literature and a case that I experienced. In late cerebral radionecrosis, there are typical coagulation necrosis areas containing fibrinoid necrosis with occlusion of the lumina and poorly active inflammatory areas with many inflammatory ghost cells, focal perivascular lymphocytes, hyalinized vessels, and telangiectatic vascularization near and in the necrotic tissue, and more active inflammatory areas formed as a partial rim of the reactive zone by perivascular lymphocytes, much vascularization, and glial fibrillary acidic protein (GFAP)-positive astrocytes at the corticomedullary border adjacent to necrotic tissue in the white matter. It is difficult to believe that coagulation necrosis occurs without first disordering the vascular endothelial cells because fibrinoid necrosis is a main feature and a diffusely multiple lesion in late cerebral radionecrosis. Because various histological findings do develop, progress, and extend sporadically at different areas and times in the irradiated field of the brain for a long time after radiation, uncontrolled chronic inflammation containing various cytokine secretions may also play a key role in progression of this radionecrosis. Evaluation of the mechanism of the development/aggravation of late cerebral radionecrosis requires a further study for abnormal cytokine secretions and aberrant inflammatory reactions. (author)

  19. Self-expanding stent-assisted middle cerebral artery recanalization: technical note

    Energy Technology Data Exchange (ETDEWEB)

    Sauvageau, Eric [State University of New York, Department of Neurosurgery, School of Medicine and Biomedical Sciences, Buffalo, NY (United States); State University of New York, Toshiba Stroke Research Center, School of Medicine and Biomedical Sciences, Buffalo, NY (United States); Levy, Elad I. [State University of New York, Department of Neurosurgery, School of Medicine and Biomedical Sciences, Buffalo, NY (United States); State University of New York, Department of Radiology, School of Medicine and Biomedical Sciences, Buffalo, NY (United States); State University of New York, Toshiba Stroke Research Center, School of Medicine and Biomedical Sciences, Buffalo, NY (United States)

    2006-06-15

    Investigation into pharmacological and mechanical means of improving recanalization rates by intraarterial therapy has led to technological development. Angiographic recanalization has been associated with improvement in clinical outcome. A clot retriever has recently joined an imperfect armamentarium for intraarterial stroke therapy. In this report, we describe successful recanalization of an acute thrombotic occlusion of the inferior division of the middle cerebral artery (MCA) achieved with a self-expanding stent. An 82-year-old woman with a history of coronary atherosclerosis and previous cerebellar hemorrhage presented with a National Institutes of Health Stroke Scale (NIHSS) score of 11. Perfusion computed tomography imaging showed a left MCA territory deficit. Diffusion-weighted magnetic resonance (MR) imaging revealed a small punctiform insular hyperintensity. Angiography documented occlusion of the inferior division of the left MCA (Thrombolysis in Myocardial Infarction or Thrombolysis in Cerebral Infarction, TIMI/TICI, grade 0). Intraarterial delivery of eptifibatide to the occlusion site failed to recanalize the vessel. Deployment of a self-expanding stent in the occluded segment resulted in complete revascularization of the distal vascular bed. Angiography performed on the next day confirmed patency of the stented vessel segment (TIMI/TICI 3). The patient was discharged 3 days after the procedure (NIHSS 3). MR angiography obtained 3 months after the procedure documented left MCA patency. This technique may have a role worthy of further investigation in acute stroke therapy. (orig.)

  20. Chronic cocaine disrupts neurovascular networks and cerebral function: optical imaging studies in rodents

    Science.gov (United States)

    Zhang, Qiujia; You, Jiang; Volkow, Nora D.; Choi, Jeonghun; Yin, Wei; Wang, Wei; Pan, Yingtian; Du, Congwu

    2016-02-01

    Cocaine abuse can lead to cerebral strokes and hemorrhages secondary to cocaine's cerebrovascular effects, which are poorly understood. We assessed cocaine's effects on cerebrovascular anatomy and function in the somatosensory cortex of the rat's brain. Optical coherence tomography was used for in vivo imaging of three-dimensional cerebral blood flow (CBF) networks and to quantify CBF velocities (CBFv), and multiwavelength laser-speckle-imaging was used to simultaneously measure changes in CBFv, oxygenated (Δ[HbO2]) and deoxygenated hemoglobin (Δ[HbR]) concentrations prior to and after an acute cocaine challenge in chronically cocaine exposed rats. Immunofluorescence techniques on brain slices were used to quantify microvasculature density and levels of vascular endothelial growth factor (VEGF). After chronic cocaine (2 and 4 weeks), CBFv in small vessels decreased, whereas vasculature density and VEGF levels increased. Acute cocaine further reduced CBFv and decreased Δ[HbO2] and this decline was larger and longer lasting in 4 weeks than 2 weeks cocaine-exposed rats, which indicates that risk for ischemia is heightened during intoxication and that it increases with chronic exposures. These results provide evidence of cocaine-induced angiogenesis in cortex. The CBF reduction after chronic cocaine exposure, despite the increases in vessel density, indicate that angiogenesis was insufficient to compensate for cocaine-induced disruption of cerebrovascular function.

  1. Clinical and pathological study on 10 cases of cerebral lobe hemorrhage related with cerebral amyloid angiopathy

    Directory of Open Access Journals (Sweden)

    Xiao-qi LI

    2015-07-01

    Full Text Available Objective To summarize the clinical data and pathological features of 10 cases of cerebral lobar hemorrhage related with cerebral amyloid angiopathy (CAA diagnosed pathologically, thereby to improve the knowledge and diagnosis of the disease. Methods The clinical data of 10 cases of cerebral lobar hemorrhage related with CAA, collected in the General Hospital of Shenyang Command from 1983 up to now, were retrospectively analyzed, and the clinical and neuropathological features of these cases were summarized. Results Of the 10 patients, 2 suffered from single lobar hemorrhage and 8 multiple lobar hemorrhage, all of them were confirmed pathologically to have ruptured into the subarachnoid space. Pathological examination revealed microaneurysm in 2 cases, "double barrel" change in 4 cases, multiple arteriolar clusters in 5 cases, obliterative onion-liked intima change in 4 cases, and fibrinoid necrosis of vessel wall in 7 cases. In addition, neurofibrillary tangles were found in 8 cases, and senile plaque was observed in 5 cases. Conclusions Cerebral lobar hemorrhage related with CAA is mainly located in the parietal, temporal and occipital lobes, readily breaking into the subarachnoid space, and it is often multiple and recurrent. The CAA associated microvasculopathy was found frequently in the autopsy sample of CAA related cerebral lobar hemorrhage, and it may contribute to the pathogenesis of cerebral hemorrhage. DOI: 10.11855/j.issn.0577-7402.2015.07.04

  2. Arterial tree asymmetry reduces cerebral pulsatility.

    Science.gov (United States)

    Vrselja, Zvonimir; Brkic, Hrvoje; Curic, Goran

    2015-11-01

    With each heartbeat, pressure wave (PW) propagates from aorta toward periphery. In cerebral circulation, at the level of circle of Willis (CW), four arteries and four PWs converge. Since the interference is an elemental property of the wave, PWs interfere at the level of CW. We hypothesize that the asymmetry of brain-supplying arteries (that join to form CW) creates phase difference between the four PWs that interfere at the level of CW and reduce downstream cerebral pulsatility. To best of our knowledge, the data about the sequence of PWs' arrival into the cerebral circulation is lacking. Evident imperfect bilateral symmetry of the vessels results with different path length of brain-supplying arteries, hence, PWs should arrive into the head at different times. The probabilistic calculation shows that asynchronous arrival is more probable than synchronous. The importance of PWs for the cerebral circulation is highlighted by the observation that barotrauma protection mechanisms are more influenced by the crest of PW (pulse pressure) than by the mean arterial pressure. In addition, an increased arterial pulsatility is associated with several brain pathologies. We created simple computational models of four converging arteries and found that asynchronous arrival of the PWs results with lower maximum pressure, slower rate of pressure amplification and lower downstream pulsatility. In analogy, the asynchronous arrival of the pressure waves into the cerebral circulation should decrease blood flow pulsatility and lower transmission of kinetic energy on arterial wall. We conclude that asynchronous arrival of PWs into the cerebral circulation influences cerebral hemodynamics and represents a physiological necessity. PMID:26277658

  3. Vessel wall enhancement in the diagnosis and management of primary angiitis of the central nervous system in children.

    Science.gov (United States)

    Ohno, Koyo; Saito, Yoshiaki; Kurata, Hirofumi; Saiki, Yusuke; Ohtahara, Hiroko; Yoshioka, Hiroki; Yamashita, Eijiro; Fujii, Shinya; Maegaki, Yoshihiro

    2016-08-01

    We describe two cases of primary angiitis of the central nervous system in children (cPACNS) diagnosed by vessel wall contrast enhancement on magnetic resonance imaging (MRI). Both patients developed acute cerebral infarction after fever and malaise. In patient 1, a 7-month-old boy, MRI revealed extensive cerebral infarction in the right middle cerebral artery (MCA) area and stenosis at the M1 portion of the right MCA. Oral glucocorticoid therapy was initiated. Vessel wall enhancement was ameliorated 3months after onset, and stenosis was mostly restored. Patient 2, a 5-year-old boy, suffered from cerebral infarction in the left MCA area, and stenosis was identified in the left internal carotid artery, left MCA, and left posterior cerebral artery. Although vessel wall enhancement was reduced after glucocorticoid therapy, vessel wall enhancement of left MCA re-emerged, accompanied by increased erythrocyte sedimentation rate (ESR) and, decreased cerebral blood flow (CBF) in the affected hemisphere. Intravenous methylprednisolone therapy followed by oral glucocorticoid and mycophenolate mofetil resulted in resolution of these findings. Vessel wall enhancement is a promising finding in the diagnosis of cPACNS. Disease flares occur rarely in medium-to-large vessel cPACNS during dose tapering. Vessel wall enhancement, ESR, and CBF may be useful for the assessment of the activity of angiitis. PMID:26852378

  4. Free Flow of Qi in Conception Vessel and Governor Vessel Leading to Longevity

    Institute of Scientific and Technical Information of China (English)

    GUI Liang; CUI Yi-jun

    2003-01-01

    @@ Circle of Qi in human body, is namely Conception Vessel and Governor Vessel. It is divided into Large and Small Circle of qi. Small Circle of qi means that qi flows along the Circle of qi. Large Circle of qi means that vitality flows along the Circle of qi.Health-preserving expert holds that, if someone can achieve the skill of Small Circle of qi, he can return to juvenscence in essence, consolidating the body and achieve longevity.

  5. Brain blood vessel segmentation using line-shaped profiles

    International Nuclear Information System (INIS)

    Segmentation of cerebral blood vessels is of great importance in diagnostic and clinical applications, especially for embolization of cerebral aneurysms and arteriovenous malformations (AVMs). In order to perform embolization of the AVM, the structural and geometric information of blood vessels from 3D images is of utmost importance. For this reason, the in-depth segmentation of cerebral blood vessels is usually done as a fusion of different segmentation techniques, often requiring extensive user interaction. In this paper we introduce the idea of line-shaped profiling with an application to brain blood vessel and AVM segmentation, efficient both in terms of resolving details and in terms of computation time. Our method takes into account both local proximate and wider neighbourhood of the processed pixel, which makes it efficient for segmenting large blood vessel tree structures, as well as fine structures of the AVMs. Another advantage of our method is that it requires selection of only one parameter to perform segmentation, yielding very little user interaction. (paper)

  6. 46 CFR 178.430 - Drainage of well deck vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of well deck vessels. 178.430 Section 178.430 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS... probable conditions of list and trim. (d) The deck of well deck vessel that operates on exposed...

  7. Vessel Arrival Info - Legacy

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Arrival Info is a spreadsheet that gets filled out during the initial stage of the debriefing process by the debriefer. It contains vessel name, trip...

  8. Probabilistic retinal vessel segmentation

    Science.gov (United States)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  9. Guam Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Guam. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  10. Florida Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Florida. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  11. Hippocampal neurogenesis in the new model of global cerebral ischemia

    Science.gov (United States)

    Kisel, A. A.; Chernysheva, G. A.; Smol'yakova, V. I.; Savchenko, R. R.; Plotnikov, M. B.; Khodanovich, M. Yu.

    2015-11-01

    The study aimed to evaluate the changes of hippocampal neurogenesis in a new model of global transient cerebral ischemia which was performed by the occlusion of the three main vessels (tr. brachiocephalicus, a. subclavia sinistra, and a. carotis communis sinistra) branching from the aortic arch and supplying the brain. Global transitory cerebral ischemia was modeled on male rats (weight = 250-300 g) under chloral hydrate with artificial lung ventilation. Animals after the same surgical operation without vessel occlusion served as sham-operated controls. The number of DCX-positive (doublecortin, the marker of immature neurons) cells in dentate gyrus (DG) and CA1-CA3 fields of hippocampus was counted at the 31st day after ischemia modeling. It was revealed that global cerebral ischemia decreased neurogenesis in dentate gyrus in comparison with the sham-operated group (P<0.05) while neurogenesis in CA1-CA3 fields was increased as compared to the control (P<0.05).

  12. Study on cerebral microcirculation by Optical Doppler Tomography

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Optical Doppler Tomography (ODT) provides a novel method to measure the blood flow velocity in vessels with the diameter at micrometer scale. Rats with cranial window are used as a model, and the changes in the blood flow velocity of cerebral arterioles in sensory cortex are measured in real time with an established ODT system, under electrical stimulation and drug administration. The results show significant differences in the blood flow velocity between experimental groups and control groups, demonstrating the feasibility of ODT in the cerebral microcircula- tion study. Compared with the conventional Doppler ultrasound, ODT provides much higher spatial resolution, and thus holds a promising future in the application of the cerebral microcirculation study, especially in the observation of the blood flow velocity in micrometer scale vessels.

  13. [Stent-Assisted Coil Embolization of a Dissecting Aneurysm of the Posterior Cerebral Artery: A Case Report].

    Science.gov (United States)

    Haruma, Jun; Sugiu, Kenji; Yukiue, Tadato; Sasaki, Tatsuya; Hattori, Yasuhiko; Kobayashi, Kazuki; Yoshida, Hideyuki; Muneda, Koji; Date, Isao

    2015-12-01

    Dissecting aneurysms of the posterior cerebral artery (PCA) are rare, especially those at the P1 segment. Here, we describe the case of a 57-year-old woman with a subarachnoid hemorrhage (SAH). Computed tomography angiography (CTA) and digital subtraction angiography (DSA) revealed a small (3 mm) dissecting aneurysm with the typical pearl-and-string sign at the right P1 segment. Fourteen days after onset, the patient developed aphasia. DSA revealed vasospasm of the right middle cerebral artery, and we performed endovascular treatment by the intra-arterial injection of 1-(5-isoquinolinesulfonyl) homopiperazine. After this treatment, the patient's symptoms recovered immediately. Vertebral angiography revealed enlargement of the dissecting aneurysm (up to 7 mm diameter). We started a loading dose of 300 mg aspirin and 400 mg clopidogrel after observing growth of the aneurysm. Fifteen days after onset, we performed a stent-assisted coil embolization, and obtained nearly complete obliteration of the aneurysm with preserved patency of the parent artery. Six-month follow-up DSA demonstrated complete occlusion of the aneurysm with good patency of the stented PCA; the patient was at modified Rankin Scale 1. In the treatment of ruptured dissecting aneurysms, parent vessel occlusion (PVO) with aneurysm is common. However, PVO may cause both cerebral infarction of the distal area and perforator occlusion of the occluded vessel. Stent-assisted coil embolization can preserve parent vessel flow and obliterate the aneurysm. Stents offer a therapeutic alternative for PCA dissecting aneurysms, especially when PVO cannot be tolerated. PMID:26646176

  14. Large containment vessel for nuclear power station

    International Nuclear Information System (INIS)

    Reactor containment vessels are installed for preventing scattering radioactive substances at the time of breaking of nuclear equipments, and they have grown large with the increase of reactor power output. As for the types of containment vessels, self-supporting type, concrete liner type, and hybrid type are named, and there are cylindrical, conical, spherical, and electric bulb forms. Reactor pressure vessels and important equipments and pipings are contained in containment vessels, and the measures for safety and in-service inspection are the factors enlarging the containment vessels. The present tendency is to enlarge containment vessels so as to obtain large free space for taking sufficient safety measures and carrying out in-service inspection. The steels for contruction self-supporting containment vessels must be tough enough at low temperature, have good weldability, not require stress relief annealing in field welding, and have stable quality. In case of using SPV-50, the plate thickness required is smaller than 38 mm, the limit that annealing is not required, even when the internal pressure and earthquake load are taken into account. Spherical containment vessels used for small output so far became to be used also for large power output because the plate thickness required is relatively small, sufficient working space can be obtained, and the manufacture is easy. (Kako, I.)

  15. Cerebral angiography in leptomeningitis and cerebritis

    International Nuclear Information System (INIS)

    This is a report of the cerebral angiographic findings in cases of meningitis and cerebritis. Fifty-nine patients, 38 of whom were under 1 year of age, underwent cerebral angiography by means of femoral catheterization. All the patients had signs of increased intracranial pressure, seizures, focal cerebral signs, positive transillumination of the head, and or abnormal brain scan findings. A few patients who did not respond to systemic antibiotics as was expected were also evaluated by means of cerebral angiography. The following characteristic angiographic findings were observed in 18 cases of active meningitis: (1) A hasy appearance around the arteries (halo formation) between the late arterial and capillary phases. (2) Narrowing of the arteries in the basal cistern. This sometimes extended to the peripheral arteries. (3) Irregular caliber following the narrowing of arteries (in few cases). (4) Circulation time so slow that veins could be seen in the late arterial phase. (5) Halo formation around the anterior chroidal artery and the clear appearance of the choroid plexus in the venous phase (when the infectious process reached the choroid plexus). Cerebritis could be identified on the angiograms by two signs: (1) local swelling of the brain (mainly the temporal lobe) and (2) staining around the veins without any abnormal signs in the arterial phase (laminar staining). In conclusion, angiography is a meaningful test by which to determine the phase of meningitis and cerebritis. These two conditions should be treated based on valid information obtained by means of CSF examinations and neuroradiological tests, especially CT scan and cerebral angiography. (author)

  16. ALICE HMPID Radiator Vessel

    CERN Multimedia

    2003-01-01

    View of the radiator vessels of the ALICE/HMPID mounted on the support frame. Each HMPID module is equipped with 3 indipendent radiator vessels made out of neoceram and fused silica (quartz) windows glued together. The spacers inside the vessel are needed to stand the hydrostatic pressure. http://alice-hmpid.web.cern.ch/alice-hmpid

  17. Intracranial vessel wall imaging at 7.0 tesla MRI

    OpenAIRE

    van der Kolk, A.G.

    2014-01-01

    Intracranial atherosclerosis is one of the main causes of ischemic stroke. Current conventional imaging techniques assessing intracranial arterial disease in vivo only visualize the vessel wall lumen instead of the pathological vessel wall itself. Therefore, not much is known about the imaging characteristics of intracranial vessel wall pathology in vivo, and distinguishing different vessel wall pathologies remains difficult. In this thesis, several 7.0 tesla MRI sequences – first with small ...

  18. Surgical strategy for cerebral arteriovenous malformation with acute hemorrhage

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Presently, there have been craniocerebral operation, interventional embolization,stereotactic radiotherapy and other methods in treating cerebral arteriovenous malformation (AVM).However, the standard of different therapeutic regimens of cerebral AVM at the acute stage of hemorrhage has not been completely identified.OBJECTIVE: To observe the clinical characteristics and therapeutic effects of AVM at the acute stage of hemorrhage in patients, and to analyze corresponding therapeutic strategies.DESIGN: Non-randomized clinical observation.SETTING: Department of Neurosurgery, Foshan First People's Hospital, Sun Yat-sen University.PARTICIPANTS: Forty-six patients with cerebral AVM complicated by hemorrhage admitted to Department of Neurosurgery, Foshan First People's Hospital between January 1999 and December 2006,were involved in this study. All the patients were confirmed as cerebral AVM complicated by hemorrhage by brain angiography or/and postoperational pathology. The involved patients, 32 males and 14 females,averaged 25 years old, ranging from 6 to 62 years. Informed consents of therapeutic items were obtained from the relatives of all the patients.METHODS: ①On admission, skull CT and brain angiography were conducted in the involved subjects. ②The therapeutic method was confirmed according to the consciousness, hematoma region, hematoma volume,imageological results following comprehensive analysis: DSA examination was permitted to identify the size and position of abnormal vessel mass, and the distribution of feeding artery and draining vein. Craniocerebral operation was carried out as early as possible in patients with severe or progressive conscious disturbance, in which most of hematoma with obvious occupied effect or cerebral hernia was located in lobe of brain. The primary thing was to clean intracerebral hematoma for in time decompression. According to different situations, corresponding therapeutic measures were used for resecting abnormal

  19. The Clinical analyse of 206 patients of cerebral infarction (Abstract)

    Institute of Scientific and Technical Information of China (English)

    Mai Mai; Ti Yi Ming; Ghen Bo

    2000-01-01

    This thesis make a summary and analyse to 206 patients of cerebral infarction. The morbidity of the age from 51 to 70 is thehighist in 206 patients. It is 75.3 % a mong the patient that hypertension is original. The frequently-occurring cerebral in farction patient are 36.8 % and it is the highist. Because our hospital have purchased CT machinery, we can early diagnose cerebral infarction and do dissolving thrombus in early time, controlling blood pressure, clearing away free radical, dehydrating, di lating cerebral blood vessel, recovering treat early and so on. It reduced the appear ing of conplication and the death rate and viability by oneselfare improved obvious lv.

  20. Reactor vessel lower head integrity

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, A.M.

    1997-02-01

    On March 28, 1979, the Three Mile Island Unit 2 (TMI-2) nuclear power plant underwent a prolonged small break loss-of-coolant accident that resulted in severe damage to the reactor core. Post-accident examinations of the TMI-2 reactor core and lower plenum found that approximately 19,000 kg (19 metric tons) of molten material had relocated onto the lower head of the reactor vessel. Results of the OECD TMI-2 Vessel Investigation Project concluded that a localized hot spot of approximately 1 meter diameter had existed on the lower head. The maximum temperature on the inner surface of the reactor pressure vessel (RPV) in this region reached 1100{degrees}C and remained at that temperature for approximately 30 minutes before cooling occurred. Even under the combined loads of high temperature and high primary system pressure, the TMI-2 RPV did not fail. (i.e. The pressure varied from about 8.5 to 15 MPa during the four-hour period following the relocation of melt to the lower plenum.) Analyses of RPV failure under these conditions, using state-of-the-art computer codes, predicted that the RPV should have failed via local or global creep rupture. However, the vessel did not fail; and it has been hypothesized that rapid cooling of the debris and the vessel wall by water that was present in the lower plenum played an important role in maintaining RPV integrity during the accident. Although the exact mechanism(s) of how such cooling occurs is not known, it has been speculated that cooling in a small gap between the RPV wall and the crust, and/or in cracks within the debris itself, could result in sufficient cooling to maintain RPV integrity. Experimental data are needed to provide the basis to better understand these phenomena and improve models of RPV failure in severe accident codes.

  1. China's coastal small vessels manning problem and countermeasure research%我国沿海小型运输船舶配员问题与对策研究

    Institute of Scientific and Technical Information of China (English)

    郭全保

    2015-01-01

    The ship equipped with enough qualified crew is the necessary condition to ensure the safety of ship sailing, but at present our country some small transport ships still exist the problem of shortage of manning. To this, must strengthen the penalties lack of manning of ships, strengthening the vessel visa and field investigation dynamics, the introduction of "the good faith management" mechanism, strengthen the management of shipping companies.%船舶配备足够合格的船员是保证船舶安全航行的必要条件,但是目前我国部分小型运输船舶仍然存在着配员不足的问题.对此,必须加强配员不足船舶的处罚力度,加强船舶签证管理和现场查处力度,引入"诚信管理"机制,加强航运公司管理.

  2. Serial neuroradiological studies in focal cerebritis

    Energy Technology Data Exchange (ETDEWEB)

    Hatta, S. (Dept. of Neurology, Juntendo Univ. School of Medicine, Tokyo (Japan)); Mochizuki, H. (Dept. of Neurology, Juntendo Univ. School of Medicine, Tokyo (Japan)); Kuru, Y. (Dept. of Radiology, Juntendo Univ. School of Medicine, Tokyo (Japan)); Miwa, H. (Dept. of Neurology, Juntendo Univ. School of Medicine, Tokyo (Japan)); Kondo, T. (Dept. of Neurology, Juntendo Univ. School of Medicine, Tokyo (Japan)); Mori, H. (Dept. of Neurology, Juntendo Univ. School of Medicine, Tokyo (Japan)); Mizuno, Y. (Dept. of Neurology, Juntendo Univ. School of Medicine, Tokyo (Japan))

    1994-05-01

    We report serial neuroradiological studies in a patient with focal cerebritis in the head of the left caudate nucleus. On the day after the onset of symptoms, CT showed an ill-defined low density lesion. The lack of contrast enhancement appeared to be the most important finding for differentiating focal cerebritis from an encapsulated brain abscess or a tumour. MRI two days later revealed the centre of the lesion to be of slightly low intensity on T1-weighted inversion recovery (IR) images and very low intensity on T2-weighted spin echo images, which appeared to correspond to the early cerebritis stage of experimentally induced cerebritis and brain abscess. Ten days after the onset of symptoms, CT revealed a thin ring of enhancement in the head of the caudate nucleus, and a similar small ring was seen in the hypothalamus 16 days after the onset, corresponding to the late cerebritis stage. MRI nine days later revealed ill-defined high signal lesions within the involved area on the T1-weighted IR images. To our knowledge, this is the first published MRI documentation of the early cerebritis stage developing into an encapsulated brain abscess. The mechanisms underlying of these radiographic changes are discussed. (orig.)

  3. Serial neuroradiological studies in focal cerebritis

    International Nuclear Information System (INIS)

    We report serial neuroradiological studies in a patient with focal cerebritis in the head of the left caudate nucleus. On the day after the onset of symptoms, CT showed an ill-defined low density lesion. The lack of contrast enhancement appeared to be the most important finding for differentiating focal cerebritis from an encapsulated brain abscess or a tumour. MRI two days later revealed the centre of the lesion to be of slightly low intensity on T1-weighted inversion recovery (IR) images and very low intensity on T2-weighted spin echo images, which appeared to correspond to the early cerebritis stage of experimentally induced cerebritis and brain abscess. Ten days after the onset of symptoms, CT revealed a thin ring of enhancement in the head of the caudate nucleus, and a similar small ring was seen in the hypothalamus 16 days after the onset, corresponding to the late cerebritis stage. MRI nine days later revealed ill-defined high signal lesions within the involved area on the T1-weighted IR images. To our knowledge, this is the first published MRI documentation of the early cerebritis stage developing into an encapsulated brain abscess. The mechanisms underlying of these radiographic changes are discussed. (orig.)

  4. Onyx® in endovascular treatment of cerebral arteriovenous malformations – a review

    International Nuclear Information System (INIS)

    Arteriovenous malformation (AVM) is an abnormal connection between arteries and veins, bypassing the capillary system. In most cases, the disorder may be asymptomatic. The objective of endovascular AVM treatment is set individually for each case upon consultations with a neurosurgeon and a neurologist. The endpoint of the treatment should consist in prevention of AVM bleeding in a management procedure characterized by a significantly lower risk of complications as compared to the natural history of AVM. Endovascular interventions within AVM may include curative exclusion of AVM from circulation, embolization adjuvant to resection or radiation therapy, targeted closure of a previously identified bleeding site as well as palliative embolization. Onyx was first described in the 1990s. It is a non-adhesive and radiolucent compound. Onyx-based closure of the lumen of the targeted vessel is obtained by means of precipitation. The process is enhanced peripherally to the main flux of the injected mixture. This facilitates angiographic monitoring of embolization at any stage. The degree of lumen closure is associated with the location of the vessel. Supratentorial and cortical locations are most advantageous. Dense and plexiform structure of AVM nidus as well as a low number of supplying vessels and a single superficial drainage vein are usually advantageous for Onyx administration. Unfavorable factors include nidus drainage into multiple compartments as well as multiarterial supply of the AVM, particularly from meningeal arteries, en-passant arteries or perforating feeders. Onyx appears to be a safe and efficient material for embolization of cerebral AVMs, also in cases of intracranial bleeding associated with AVM. Curative embolization of small cerebral AVMs is an efficient and safe alternative to neurosurgical and radiosurgical methods. Careful angiographic assessment of individual arteriovenous malformations should be performed before each Onyx administration

  5. Neurovascular lessons from a pair of identical twins with cerebral aneurysms

    OpenAIRE

    Sharma, P.; Brown, M.

    2001-01-01

    A pair of hypertensive identical twins are reported, one of whom was non-compliant with her antihypertension medication, and after a subarachnoid haemorrhage was found to have multiple cerebral aneurysms. The other asymptomatic compliant twin was noted to have only a single small cerebral aneurysm. As both identical twins are likely to share the same cerebral vascular architecture it is suggested that good control of blood pressure contributed to the cerebral vascular integrity of the asympto...

  6. Measurement of cerebral circulation time in man

    International Nuclear Information System (INIS)

    A simple, inexpensive method for measuring the cerebral circulation time (CCT) was developed. The CCT was considered to be equal to the time that an intravenously injected bolus of sodium pertechnetate Tc 99m took to go from the subclavian artery to the posterior venous confluence. The dilution curves were externally recorded at these two vessels. Particular attenion was given to the curve treatment. The computer programmes were specially conceived in order to detect and, if possible, correct the experimental curve defects. Several reliability criteria were also defined in order to test the validity of each measurement. From a physiological point of view, the CCT is equal to the ratio of the global cerebral blood volume to the global cerebral blood flow. Thus, it can be widely applied in clinical research. For example, in a study of the relationship between CCT and age, sex and light cerebrovascular impairment, the technique was sensitive enough to discriminate between healthy subjects and patients suffering from-transient ischemic attack, or regressive stroke, and to show the action of a drug on the cerebral circulation in such patients. (orig.)

  7. Behcet's disease with cerebral vasculitis

    International Nuclear Information System (INIS)

    The case presented illustrates the diagnostic dilemma off neurological involvement in Behcet's disease and other inflammatory diseases. 'Psychiatric' symptoms were present for 2 years without abnormalities on SPECT or MRI and without CSF pleocytosis. Even at the time of fitting, no CSF abnormalities were observed. The preceding psychiatric presentations may have been due to cerebral vasculitis that was exacerbated by withdrawal of steroids. Magnetic resonance imaging is currently the most sensitive imaging modality. Lesions are usually in the brainstem, cerebellum, basal ganglia region or periventricular white matter, and the pons and the mesencephalon are commonly affected. In our patient there was no diencephalic or brainstem involvement. The inflammatory process can appear as a very large lesion, with gadolinium enhancement and significant mass effect, as in our patient. Brain magnetic resonance imaging. Postgadolinium-diethylenetriamine pentaacetic acid, axial image shows two large lesions in the right frontal lobe, with the larger, posterior lesion demonstrating vivid ring enhancement. A central nodule is isodense, with the cerebral white matter within the larger lesion. Surrounding low T1 signal involves the hemispheric white matter without cortical extension and is consistent with vasogenic oedema. Minor mass effect is demonstrated with bowing of the anterior falx cerebri to the left. Biopsy shows prominent fibrinoid necrosis in small calibre postcapillary venules and cerebral white matter. There are surrounding acute and chronic inflammatory cells and nuclear debris, consistent with vasculitis

  8. MRI - a noninvasive tool for evaluating therapeutic embolisation of cerebral arteriovenous malformations

    International Nuclear Information System (INIS)

    Of 86 patients with whose cerebral arteriovenous malformations (AVMs) were embolised in the period 1985-1990 29 were examined by high-field spin-echo (SE) magnetic resonance imaging (MRI) after endovascular therapy with histoacryl-lipiodol. Embolisation-related changes in the nidus of the AVM and in the surrounding brain parenchyma were assessed. Results were compared with pretreatment MR and CT, and with follow-up angiograms in all patients. In accordance with angiographic findings, complete obliteration of pathological vessels was noted in 7 patients (24.1%) and partial occlusion in 22 (75.9%); small ischaemic infarcts were observed in 8 patients (27.6%) and extravascular deposits of blood breakdown products were seen in 3 (10.3%). MRI is a valuable noninvasive technique for assessing morphology and haemodynamics of cerebral AVMs before and after treatment. However, following embolotherapy, variable effects on signal intensity in vascular lumina caused by flowing blood, thrombosis and the embolisation agent have to be carefully analysed. To assess the exact site of histoacryl-lipiodol in embolised nidus territories or small areas of possible intracerebral hemorrhage, the time interval between endovascular therapy and MR examinations may have to be modified. (orig.)

  9. PERIVASCULAR ADIPOSE TISSUE AND VESSEL CONTRACTILITY IN HEALTH AND OBESITY

    OpenAIRE

    Aghamohammadzadeh, Reza

    2014-01-01

    White adipocytes surround almost all blood vessels in the human body. It was thought previously that these cells merely provide mechanical support for the adjacent small vessels and are little more than fat storage units. Recent studies have identified these cells as metabolic and vasoactive engines that produce and secrete molecules that can affect the function of their adjacent small vessels. The adipocytes and a number of other cell types (including inflammatory cells) surrounding the vess...

  10. Rupture safety for nuclear reactor pressure vessels

    International Nuclear Information System (INIS)

    This safety device for pressure vessels with cooling water inlet and outlet supports is to catch flying parts in the case of a rupture and to convert their energy into forming work without rupturing itself. A steel cladding is used for this purpose which surrounds the lower part of the pressure vessel as protective container like a pot, right up to the coolant supports. In order to keep the possible acceleration paths of the rupture pieces as small as possible, the gap between the two vessels is limited to a small tolerance to compensate for the differences in thermal expansion. In order to take up the compensating pressure after rupture of the reactor pressure vessel, the cylindrical part of the protective vessel requires double wall thickness like the concave floor. The cylindrical part is thus cladded by a cylindrical protective ring of the same wall thickness or by a multilayer sheet cladding which can be easily fabricated, transported and assembled. The cylindrical and concave part of the inner protective vessel have uniform wall thickness. This hence ensures that the elastic form changing is uniformly distributed over the height of the protective vessel. (HP)

  11. Cerebral Palsy (CP) Quiz

    Science.gov (United States)

    ... Submit Button Past Emails CDC Features Pop Quiz: Cerebral Palsy Language: English Español (Spanish) Recommend on Facebook Tweet ... Sandy is the parent of a child with cerebral palsy and the Board President of Gio’s Garden , a ...

  12. Reversible cerebral vasoconstriction syndrome

    Directory of Open Access Journals (Sweden)

    Saini Monica

    2009-01-01

    Full Text Available Reversible cerebral vasoconstriction syndromes (RCVS are a group of disorders that have in common an acute presentation with headache, reversible vasoconstriction of cerebral arteries, with or without neurological signs and symptoms. In contrast to primary central nervous system vasculitis, they have a relatively benign course. We describe here a patient who was diagnosed with RCVS.

  13. Clinical studies on cerebral infarction

    International Nuclear Information System (INIS)

    Hemorrhagic infarction (HI) is termed as the infarction in which a large part of the necrotic tissue is stippled with small hemorrhage. The pathogenetic mechanism of this disease still remains controversial. Cerebral infarction has long been divided into two subtypes-thrombosis and embolism-according to the pathogenetic mechanisms. Clinical studies were carried out in 31 cases of HI with cerebral thrombosis. CT findings of these cases were classified into five groups according to both size of low density area which indicates regions of infarction and distribution of arterial supply. The low density area of Type I-Type III were observed in the area of the middle cerebral artery. That of Type IV was observed in the area of the internal capsule and basal ganglia. That of Type V was observed in the area of the posterior cerebral artery. CT reveals two patterns of HI -pattern A and pattern B-. The CT finding of pattern A is appearance of high density area in the low density area. The CT finding of pattern B is appearance of iso density area in the low density area. rCBF was measured by 133Xe inhalation technique in 21 patients with CT type I, II and III. Thereafter, with regard to the various findings in CT, the clinical findings and CBF findings, a comparative study was carried out on these ten groups. From the results of present studies, it is concluded that sequential changes of CBF in cases with pattern A are different from those with pattern B, and that CBF measurement does not permit an estimation of a patient's chance for functionary recovery after a stroke in acute and subacute stage but permits estimation of functional outcome in chronic stage. (J.P.N.)

  14. Glycopyrrolate abolishes the exercise-induced increase in cerebral perfusion in humans

    DEFF Research Database (Denmark)

    Seifert, Thomas; Fisher, James P; Young, Colin N; Hartwich, Doreen; Ogoh, Shigehiko; Raven, Peter B; Fadel, Paul J; Secher, Niels H

    2010-01-01

    Brain blood vessels contain muscarinic receptors that are important for cerebral blood flow (CBF) regulation, but whether a cholinergic receptor mechanism is involved in the exercise-induced increase in cerebral perfusion or affects cerebral metabolism remains unknown. We evaluated CBF and cerebral......) (P <0.01) and cardiac output by approximately 40% (P <0.05), but did not affect mean arterial pressure. The central cardiovascular responses to exercise with glycopyrrolate were similar to the control responses, except that cardiac output did not increase during static handgrip with glycopyrrolate...... abolished by glycopyrrolate (P <0.05). Thus, during both cycling and static handgrip, a cholinergic receptor mechanism is important for the exercise-induced increase in cerebral perfusion without affecting the cerebral metabolic rate for oxygen....

  15. Pressure vessel design manual

    CERN Document Server

    Moss, Dennis R

    2013-01-01

    Pressure vessels are closed containers designed to hold gases or liquids at a pressure substantially different from the ambient pressure. They have a variety of applications in industry, including in oil refineries, nuclear reactors, vehicle airbrake reservoirs, and more. The pressure differential with such vessels is dangerous, and due to the risk of accident and fatality around their use, the design, manufacture, operation and inspection of pressure vessels is regulated by engineering authorities and guided by legal codes and standards. Pressure Vessel Design Manual is a solutions-focused guide to the many problems and technical challenges involved in the design of pressure vessels to match stringent standards and codes. It brings together otherwise scattered information and explanations into one easy-to-use resource to minimize research and take readers from problem to solution in the most direct manner possible. * Covers almost all problems that a working pressure vessel designer can expect to face, with ...

  16. Tumor Blood Vessel Dynamics

    Science.gov (United States)

    Munn, Lance

    2009-11-01

    ``Normalization'' of tumor blood vessels has shown promise to improve the efficacy of chemotherapeutics. In theory, anti-angiogenic drugs targeting endothelial VEGF signaling can improve vessel network structure and function, enhancing the transport of subsequent cytotoxic drugs to cancer cells. In practice, the effects are unpredictable, with varying levels of success. The predominant effects of anti-VEGF therapies are decreased vessel leakiness (hydraulic conductivity), decreased vessel diameters and pruning of the immature vessel network. It is thought that each of these can influence perfusion of the vessel network, inducing flow in regions that were previously sluggish or stagnant. Unfortunately, when anti-VEGF therapies affect vessel structure and function, the changes are dynamic and overlapping in time, and it has been difficult to identify a consistent and predictable normalization ``window'' during which perfusion and subsequent drug delivery is optimal. This is largely due to the non-linearity in the system, and the inability to distinguish the effects of decreased vessel leakiness from those due to network structural changes in clinical trials or animal studies. We have developed a mathematical model to calculate blood flow in complex tumor networks imaged by two-photon microscopy. The model incorporates the necessary and sufficient components for addressing the problem of normalization of tumor vasculature: i) lattice-Boltzmann calculations of the full flow field within the vasculature and within the tissue, ii) diffusion and convection of soluble species such as oxygen or drugs within vessels and the tissue domain, iii) distinct and spatially-resolved vessel hydraulic conductivities and permeabilities for each species, iv) erythrocyte particles advecting in the flow and delivering oxygen with real oxygen release kinetics, v) shear stress-mediated vascular remodeling. This model, guided by multi-parameter intravital imaging of tumor vessel structure

  17. Maury Journals - German Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — German vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  18. Cerebral angiography, blood flow and vascular reactivity in progressive hypertension

    Science.gov (United States)

    Li, Yunxia; Shen, Qiang; Huang, Shiliang; Li, Wei; Muir, Eric R.; Long, Justin; Duong, Timothy Q.

    2015-01-01

    Chronic hypertension alters cerebral vascular morphology, cerebral blood flow (CBF), cerebrovascular reactivity, increasing susceptibility to neurological disorders. This study evaluated: i) the lumen diameters of major cerebral and downstream arteries using magnetic resonance angiography, and ii) basal CBF, and iii) cerebrovascular reactivity to hypercapnia of multiple brain regions using arterial-spin-labeling technique in spontaneously hypertensive rats (SHR) at different stages. Comparisons were made with age-matched normotensive Wistar Kyoto (WKY) rats. In 10-week SHR, lumen diameter started to reduce, basal CBF, and hypercapnic CBF response were higher from elevated arterial blood pressure, but there was no evidence of stenosis, compared to age-matched WKY. In 20-week SHR, lumen diameter remained reduced, CBF returned toward normal from vasoconstriction, hypercapnic CBF response reversed and became smaller, but without apparent stenosis. In 40-week SHR, lumen diameter remained reduced and basal CBF further decreased, resulting in larger differences compared to WKY. There was significant stenosis in main supplying cerebral vessels. Hypercapnic CBF response further decreased, with some animals showing negative hypercapnic CBF responses in some brain regions, indicative of compromised cerebrovascular reserve. The territory with negative hypercapnia CBF responses corresponded with the severity of stenosis in arteries that supplied those territories. We also found enlargement of downstream vessels and formation of collateral vessels as compensatory responses to vasoconstriction upstream vessels. The middle cerebral and azygos arteries were amongst the most susceptible to hypertension-induced changes. Multimodal MRI provides clinically relevant data that might be useful to characterize disease pathogenesis, stage disease progression, and monitor treatment effects in hypertension. PMID:25731987

  19. 脑血管周围组织通道的功能%Functions of cerebral perivascular tissue channel

    Institute of Scientific and Technical Information of China (English)

    王俊华; 田牛; 郑世荣; 刘育英; 刘凤英; 李玉珍; 刘秀华; 赵秀梅; 韩岳; 蔡莉蓉

    2005-01-01

    tissue fluid and cerebral spinal fluid, between cerebral tissue fluid and lymphatic system, as well as among cerebral substances of every region are the neglected unknown field and the cerebral tissue channel probed in the article, which will provide significant importance in guiding prognosis and rehabilitation interventions of the disorders of central neural system(CNS).OBJECTIVE: To probe into the functions of cerebral perivascular tissue channel so as to provide the theoretical evidences for studying the mechanism on pathology and physiology of cerebral tissues.DESIGN: Completely randomized and controlled experimental study.SETTING: Department of Cardiology, General Hospital of Air Force of Chinese PLA, and Department of Pathophysiology, General Hospital of Chinese PLA.MATERIALS: The experiment was performed in the Department of Pathophysiology, General Hospital of Chinese PLA. Twenty male SD rats, body mass varied from 250 g to 300 g were purchased from Animal Center of Chinese PLA General Hospital.INTERVENTIONS: Fluorescein isothiocyanate labeled albumin(FA) with relative large molecular mass and fluorescein isothiocyanate labeled dextran(FD) with relative small molecular mass were injected in localization in the brains of rats respectively. A certain time later, both the distribution of fluorescein substance in the brain and its relation with tissue structure were observed with both tracer agents and vascular developing method simultaneously.MAIN OUTCOME MEASURES: To observe the distribution of injected tracer agents in the brain and its relation with vessels under fluorescein microscope, to compare and analyze the differences in the distribution of tracer agents of different relative molecular masses among the experimental groups.RESULTS: Fluorescein concentrated cell (Mato cell ) presented extensively around micro-vessels after injection of both FA and FD. The speed of diffusion of FD in the brain was faster than that of FA. After FA injection, fluorescein

  20. 76 FR 67255 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel KIWI CAT; Invitation for...

    Science.gov (United States)

    2011-10-31

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel KIWI CAT... the vessel KIWI CAT is: INTENDED COMMERCIAL USE OF VESSEL: ``Small vessel 12 person chartering...

  1. CEREBRAL ARTERIOVENOUS MALFORMATIONS IN CHILDREN. ENDOVASCULAR TREATMENT

    OpenAIRE

    Scheglov, D.; Zagorodniy, V.

    2013-01-01

    The objective — to learn the features of the cerebral arteriovenous malformations (АVМ) endovascular treatment in children. Materials and methods. Totally 39 children with cerebral AVMs were treated at the center from 2005 to 2012. The average age of the patients (12.6 ± 1.2) years. It was found that the most of AVMs were occurred in temporoparietal subcortical area — 46.2 % cases. Results. Small size of AVMs were detected in 15.4 % of patients, the middle — in 33.3 %, the large — in 38.5 %, ...

  2. Reversible cerebral vasconstriction syndrome: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Sub; Park, Ji Kang; Kim, Seung Hyoung; Jeong, Sun Young [Jeju National University Hospital, Jeju National University School of Medicine, Jeju (Korea, Republic of)

    2013-11-15

    We report a 46-year-old woman patient with reversible cerebral vasoconstriction syndrome (RCVS). She presented with severe headache, multiple cerebral infarction, and multifocal severe stenosis in the intracranial arteries on magnetic resonance angiography (MRA). One month after the episode, a small bowel gastrointestinal stromal tumor (GIST) was incidentally detected during the evaluation of severe anemia and GIST was removed. Follow-up MRA was performed 3 months and 1 year after an initial attack of headache, and multifocal severe intracranial arterial stenotic lesions were completely resolved, she did not experience any episode of RCVS during the 2 years.

  3. Regulation of the cerebral circulation: bedside assessment and clinical implications.

    Science.gov (United States)

    Donnelly, Joseph; Budohoski, Karol P; Smielewski, Peter; Czosnyka, Marek

    2016-01-01

    Regulation of the cerebral circulation relies on the complex interplay between cardiovascular, respiratory, and neural physiology. In health, these physiologic systems act to maintain an adequate cerebral blood flow (CBF) through modulation of hydrodynamic parameters; the resistance of cerebral vessels, and the arterial, intracranial, and venous pressures. In critical illness, however, one or more of these parameters can be compromised, raising the possibility of disturbed CBF regulation and its pathophysiologic sequelae. Rigorous assessment of the cerebral circulation requires not only measuring CBF and its hydrodynamic determinants but also assessing the stability of CBF in response to changes in arterial pressure (cerebral autoregulation), the reactivity of CBF to a vasodilator (carbon dioxide reactivity, for example), and the dynamic regulation of arterial pressure (baroreceptor sensitivity). Ideally, cerebral circulation monitors in critical care should be continuous, physically robust, allow for both regional and global CBF assessment, and be conducive to application at the bedside. Regulation of the cerebral circulation is impaired not only in primary neurologic conditions that affect the vasculature such as subarachnoid haemorrhage and stroke, but also in conditions that affect the regulation of intracranial pressure (such as traumatic brain injury and hydrocephalus) or arterial blood pressure (sepsis or cardiac dysfunction). Importantly, this impairment is often associated with poor patient outcome. At present, assessment of the cerebral circulation is primarily used as a research tool to elucidate pathophysiology or prognosis. However, when combined with other physiologic signals and online analytical techniques, cerebral circulation monitoring has the appealing potential to not only prognosticate patients, but also direct critical care management. PMID:27145751

  4. Loop Modeling Forward and Feedback Analysis in Cerebral Arteriovenous Malformation

    Directory of Open Access Journals (Sweden)

    Y. Kiran Kumar

    2013-01-01

    Full Text Available Cerebral Arteriovenous Malformation (CAVM hemodynamic in disease condition results changes in the flow and pressure level in blood vessels. Cerebral Arteriovenous Malformation (CAVM is an abnormal shunting of vessels between arteries and veins. It is one of the common Brain disorder. In general, the blood flows of cerebral region are from arteries to veins through capillary bed. This paper is focus on the creation of a new electrical model for spiral loop structures that will simulate the pressure at various locations of the CAVM Complex blood vessels. The proposed model helps Doctors to take diagnostic and treatment planning for treatment by non-invasive measurement.. This can cause rupture or decreased blood supply to the tissue through capillary causing infarct. Measuring flow and pressure without intervention along the vessel is big challenge due to loop structures of feedback and forward flows in Arteriovenous Malformation patients. In this paper, we proposed a lumped model for the spiral loop in CAVM Structures that will help doctors to find the pressure and velocity measurements non-invasively.

  5. BY FRUSTUM CONFINING VESSEL

    Directory of Open Access Journals (Sweden)

    Javad Khazaei

    2016-09-01

    Full Text Available Helical piles are environmentally friendly and economical deep foundations that, due to environmental considerations, are excellent additions to a variety of deep foundation alternatives available to the practitioner. Helical piles performance depends on soil properties, the pile geometry and soil-pile interaction. Helical piles can be a proper alternative in sensitive environmental sites if their bearing capacity is sufficient to support applied loads. The failure capacity of helical piles in this study was measured via an experimental research program that was carried out by Frustum Confining Vessel (FCV. FCV is a frustum chamber by approximately linear increase in vertical and lateral stresses along depth from top to bottom. Due to special geometry and applied bottom pressure, this apparatus is a proper choice to test small model piles which can simulate field stress conditions. Small scale helical piles are made with either single helix or more helixes and installed in fine grained sand with three various densities. Axial loading tests including compression and tension tests were performed to achieve pile ultimate capacity. The results indicate the helical piles behavior depends essentially on pile geometric characteristics, i.e. helix configuration and soil properties. According to the achievements, axial uplift capacity of helical model piles is about equal to usual steel model piles that have the helixes diameter. Helical pile compression bearing capacity is too sufficient to act as a medium pile, thus it can be substituted other piles in special geoenvironmental conditions. The bearing capacity also depends on spacing ratio, S/D, and helixes diameter.

  6. VIP/PACAP receptors in cerebral arteries of rat

    DEFF Research Database (Denmark)

    Erdling, André; Sheykhzade, Majid; Maddahi, Aida;

    2013-01-01

    BACKGROUND: Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating peptide (PACAP)-containing nerves surround cerebral blood vessels. The peptides have potent vasodilator properties via smooth muscle cell receptors and activation of adenylate cyclase. The purpose of this......-465 inhibited the VIP induced relaxation. Western blot showed the presence of the receptor proteins in cerebral vasculature and immunohistochemistry showed that all three receptors are present and located in the cytoplasm of smooth muscle cells. CONCLUSION: In both systems, the two blockers antagonized the...... relaxant VIP effect; the potency order of agonists and the immunohistochemistry suggest the presence of the dilatory VPAC(1) and VPAC(2) receptors on the smooth muscle cells....

  7. Cerebral haematocrit measurement

    International Nuclear Information System (INIS)

    Regional cerebral haematocrit was measured in a group of sixteen subjects by the single-photon emission computerized tomography method. This group included three normal subjects as controls and thirteen patients affected with ischaemic cerebral disease presenting clinically with transient ischaemic attacks-six patients - or recent cerebral stroke - seven patients. Two intravenous radioactive tracers - technetium-99m labelled autologous red blood cells and Tc-99m human serum albumin were used. Cerebral tomographic imaging was performed using a rotating scintillation camera. The values of cerebral haematocrit obtained, taken as a ratio to venous haematocrit, range between 0.65-0.88 in the subjects studied. As a general finding in normal subjects and in patients with transient ischaemic attacks, no significant difference between right and left hemispheric haematocrit value was noted. However, in the group of patients affected with stroke, a significant difference in the right versus left hemispheric Hct was observed in 3 patients, the higher Hct value corresponding to the affected side. The clinical implication is on the emphasis of cerebral Hct measurement when the measurement of cerebral blood flow or volume is sought. Also the variation in regional Hct value observed in patients with stroke, above mentioned, points to a regulation mechanism of the blood composition for optimal oxygen delivery to the brain that is impaired in these patients. 14 refs. (Author)

  8. Unilateral cerebral polymicrogyria with ipsilateral cerebral hemiatrophy

    International Nuclear Information System (INIS)

    We evaluated six children in whom MR imaging showed unilateral cerebral polymicrogyria associated with ipsilateral cerebral atrophy and ipsilateral brain stem atrophy. The aim of this study was to clarify whether this disorder based on neuroimaging constitutes a new homogeneous clinical entity. The subjects were six children whose ages at the time of MR imaging ranged from 8 months to 11 years. Their clinical and MR features were analyzed. All of the children were born between 38 and 42 weeks gestation, without any significant perinatal events. Spastic hemiplegia and epilepsy were observed in all of the patients, and mental retardation was observed in four. The MR findings included unilateral cerebral polymicrogyria associated with ipsilateral cerebral hemiatrophy and ipsilateral brain stem atrophy in all patients. The ipsilateral sylvian fissure was hypoplastic in four patients. These patients showed relatively homogeneous clinical and neuroimaging features. Although the additional clinical features varied according to the site and the extent affected by the polymicrogyria, this disorder could constitute a new relatively homogeneous clinical entity. (orig.)

  9. Unilateral cerebral polymicrogyria with ipsilateral cerebral hemiatrophy

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, Katsumi [Department of Radiology, Kyoto City Hospital, 1-2 Higashi-Takada-cho, Mibu, Nakagyo-ku, 604-8845 Kyoto (Japan); Kanda, Toyoko; Yamori, Yuriko [Department of Pediatric Neurology, St. Joseph Hospital for Handicapped Children, 603-8323 Kyoto (Japan)

    2002-10-01

    We evaluated six children in whom MR imaging showed unilateral cerebral polymicrogyria associated with ipsilateral cerebral atrophy and ipsilateral brain stem atrophy. The aim of this study was to clarify whether this disorder based on neuroimaging constitutes a new homogeneous clinical entity. The subjects were six children whose ages at the time of MR imaging ranged from 8 months to 11 years. Their clinical and MR features were analyzed. All of the children were born between 38 and 42 weeks gestation, without any significant perinatal events. Spastic hemiplegia and epilepsy were observed in all of the patients, and mental retardation was observed in four. The MR findings included unilateral cerebral polymicrogyria associated with ipsilateral cerebral hemiatrophy and ipsilateral brain stem atrophy in all patients. The ipsilateral sylvian fissure was hypoplastic in four patients. These patients showed relatively homogeneous clinical and neuroimaging features. Although the additional clinical features varied according to the site and the extent affected by the polymicrogyria, this disorder could constitute a new relatively homogeneous clinical entity. (orig.)

  10. Cerebral Lesions in Patients Undergoing Coronary Artery Bypass Grafting in Relation to Asymptomatic Carotid and Vertebral Artery Stenosis

    DEFF Research Database (Denmark)

    Wiberg, Sebastian; Schoos, Mikkel; Sillesen, Henrik; Thomsen, Carsten; Hassager, Christian; Steinbrüchel, Daniel; Schroeder, Torben; Clemmensen, Peter; Kelbæk, Henning

    2015-01-01

    OBJECTIVES: Carotid artery stenosis (CAS) and vertebral artery stenosis (VAS) are associated with cerebral infarction after coronary artery bypass graft surgery (CABG). It remains unclear whether this association is causal. We investigated the associations between neurologically asymptomatic CAS......-operative subclinical cerebral lesions. The associations between CAS/VAS post-operative cerebral lesions were investigated. RESULTS: Forty-six patients were included in the study. 13% had significant CAS and 11% had significant VAS. Thirty-five percent had new cerebral infarction postoperatively. We found a significant...... association between the presence of cerebral vessel stenosis and acute cerebral infarction (67% vs. 27%, p = 0.047). However none of the patients with stenosis had isolated cerebral lesions in the ipsilateral vascular territory. CONCLUSION: Asymptomatic CAS and VAS is common in CABG patients and is associated...

  11. Cerebral CT and MRI findings in cervicocephalic artery dissection

    Energy Technology Data Exchange (ETDEWEB)

    Pelkonen, O.; Tikkakoski, T.; Pyhtinen, J.; Sotaniemi, K. [Oulu Univ. Hospital (Finland). Dept. of Diagnostic Radiology

    2004-05-01

    PURPOSE: To explore the frequency and patterns of brain infarction and other brain manifestations in cervicocephalic artery dissection (CCAD) and to evaluate the correlation between vessel wall findings and infarctions. MATERIAL AND METHODS: The medical records and films of 136 consecutive CCAD patients diagnosed in Oulu Univ. Hospital during the 20-year period since 1982 were reviewed. Five patients with no brain imaging were excluded. RESULTS: One-hundred-and-twenty-seven patients underwent cerebral CT and four patients MRI. Brain infarction was detected in 73 patients (56%), 43 of whom had cerebral infarction associated with anterior circulation dissection and 30 cerebellar infarction associated with posterior circulation dissection. Occlusion of the dissected vessel was accompanied by infarction in 76%, irregular stenosis in 40%, and other findings in 12%. Of the anterior circulation infarctions, territorial and subcortical infarctions and territorial infarctions with fragmentation, which are considered embolic, accounted for 95%, while only 5% were in the watershed area and considered hemodynamic. Intracranial posterior circulation dissection rarely caused infarction (in 1/11 of the dissected vessels), whereas intracranial anterior circulation dissection resulted in infarction more commonly (9/12). Altogether 23% of patients with intracranial CCAD had subarachnoid hemorrhage. Hemorrhagic transformation was present in five patients. CONCLUSIONS: More than half of CCAD patients have cerebral or cerebellar infarction at CT or conventional MR imaging. Occlusion of the dissected vessel is accompanied by infarction more often than other vessel wall abnormalities. Most cerebral infarctions caused by arterial dissections are of embolic origin. Intracranial dissections cause subarachnoid hemorrhage in more than 20% of patients.

  12. PRESSURE-RESISTANT VESSEL

    NARCIS (Netherlands)

    Beukers, A.; De Jong, T.

    1997-01-01

    Abstract of WO 9717570 (A1) The invention is directed to a wheel-shaped pressure-resistant vessel for gaseous, liquid or liquefied material having a substantially rigid shape, said vessel comprising a substantially continuous shell of a fiber-reinforced resin having a central opening, an inner l

  13. Examining blood vessels

    International Nuclear Information System (INIS)

    This patent specification relates to an invention concerned with improvements in or relating to the examination of blood vessels of interest. Particles of dimensions not greater than 8 microns capable of providing detectable signals, are introduced into the blood for examination of a blood vessel. The particles may be sources of radiation, e.g. Ga68. (author)

  14. Reactor vessel sealing plug

    International Nuclear Information System (INIS)

    This invention relates to an apparatus and method for sealing the cold leg nozzles of a nuclear reactor pressure vessel from a remote location during maintenance and inspection of associated steam generators and pumps while the pressure vessel and refueling canal are filled with water. The apparatus includes a sealing plug for mechanically sealing the cold leg nozzle from the inside of a reactor pressure vessel. The sealing plugs include a primary and a secondary O-ring. An installation tool is suspended within the reactor vessel and carries the sealing plug. The tool telescopes to insert the sealing plug within the cold leg nozzle, and to subsequently remove the plug. Hydraulic means are used to activate the sealing plug, and support means serve to suspend the installation tool within the reactor vessel during installation and removal of the sealing plug

  15. State of cerebral hemodynamics in patients with cognitive dysfunction associated with atrial fibrillation

    Directory of Open Access Journals (Sweden)

    S.N. Stadnik

    2014-05-01

    Full Text Available The aim of the study was to cerebral hemodynamics in patients with cognitive dysfunction associated with atrial fibrillation (AF. Patients and methods. Fifty-six patients aged 40–75 years (the mean age was 62.7±6.3 years with nonvalvular AF caused by ischemic heart disease were examined. In 30 (53.6% patients AF was permanent; in 26 (46.4% patients, it was either persistent or paroxysmal. The exclusion criteria were as follows: past transient ischemic attacks, stroke or myocardial infarction, and severe somatic diseases. All patients with AF were evaluated for cognitive functions (using the short scale for assessing the mental status, auditory memory and associative memory (using the Schulte test, and emotional background (using the Hospital Anxiety and Depression Scale. Ultrasonography of the extracranial and intracranial vessels and registration of the average linear blood flow velocity (LBFV was performed. Results. Cognitive impairments (CI were diagnosed in 38 patients who entered the main group; patients with AF without CI comprised the control group. 82.6% of patients of the main group were diagnosed with constrictive lesion of the carotid (CA and vertebral (VA arteries of various severity; the isolated lesion of the CA was observed in 23.7% of patients, the isolated lesion of the VA in 18.4%; multiple lesions of the CA and VA in 69.4%; and the hemodynamically significant lesion, in 30.3%. In patients of the control group, constrictive lesions of the extracranial arteries were observed in 65.5% of cases. Condition of the major arteries of the head (MAH significantly affects the LBFV parameters of the intracranial arteries. In patients with multiple lesions of the CA and VA, the LBFV in the intracranial vessels was much lower than that in patients with isolated lesions of the CA and VA.The relation between the rate and severity of constrictive lesions of the MAH and the presence of AF accompanied with CI was noted in patients. Cerebral

  16. MRI of acute cerebral infarction

    International Nuclear Information System (INIS)

    Sequential changes of magnetic resonance imaging (MRI) in sixteen patients with acute cerebral infarction are studied in comparison with the findings of computed tomography (CT). The sixteen patients were examined within 36 hours from the onset of syptoms on resistive type MRI (0.15T) using T1 weighted image (IR2000/500) and T2 weighted image (SE2000/80), and on CT. In general, large infarcted lesions of the cortexsubcortex seemed to be visualized earlier than small lesions of the basal ganglia and brainstem. In 8 patients, the infarcted lesions were detected on MRI earlier than on CT. For example, early detecting time within 12 hours were 2, 6, 7, and 10 hours after onset. In two patients of this group, lesions were detected on T2 weighted image earlier than on T1-weighted image. In two cases, small lesions of the brainstem were detected only on MRI. The size of abnormal findings gradually developed and reached a maximum on days 5 to 7 sequentially. The difference between infarction and perifocal edema was not clear even on MRI. The changes gradually subsided and assumed a stable size after about 2 months. Contrast enhancement effect was observed in four patients. In two of these cases, the signal intensity of T2-weighted imaging was decreased just at the region which was enhanced with contrast medium. MRI is useful for early diagnosis of ischemic cerebral infarction, and may eludidate some aspects of the pathophysiology of ischemic stroke. (author)

  17. A patient with Moyamoya-like vessels after radiation therapy for a tumor in the basal ganglia

    Energy Technology Data Exchange (ETDEWEB)

    Ishiyama, Koichi; Tomura, Noriaki; Kato, Koki; Takahashi, Satoshi; Watarai, Jiro; Sasajima, Toshio; Mizoi, Kazuo [Akita Univ. (Japan). School of Medicine

    2001-10-01

    A patient with Moyamoya-like vessels after radiation therapy for treatment of a tumor in the basal ganglia is reported. He was diagnosed as Down syndrome at birth. He had a tumor in the left basal ganglionic region at 12 years of the age. The tumor increased in size at age 14. He underwent cerebral angiography, which did not show a stenosis nor occlusion of the internal carotid artery, anterior cerebral artery, nor the middle cerebral artery. He received radiation therapy with a total dose of 56 Gy. He presented a dressing apraxia at age 19. MRI showed cerebral infarction in the left temporo-occipital region. Right internal carotid angiography revealed a severe stenosis of the internal carotid artery and anterior cerebral artery as well as a severe stenosis of the middle cerebral artery on the right side. Moyamoya-like vessels were seen in the basal ganglionic region. Left internal carotid angiography also showed a stenosis of the internal carotid artery and anterior cerebral artery as well as a severe stenosis of the middle cerebral artery on the left side. Moyamoya-like vessels were seen in the basal ganglionic region. Leptomeningeal anastomose and transdural anastomose were bilaterally seen. These arterial occlusion and stenotic phenomenon corresponded to a previous radiation field. These Moyamoya-like vessels with arterial stenosis and occlusion were thought to be due to radiation-induced vasculopathy, because a previous cerebral angiography showed a normal caliber of cerebral arteries. This patient showed that patients with radiation therapy in their early childhood should be carefully observed considering the possibility of the phenomenon. (author)

  18. A patient with Moyamoya-like vessels after radiation therapy for a tumor in the basal ganglia

    International Nuclear Information System (INIS)

    A patient with Moyamoya-like vessels after radiation therapy for treatment of a tumor in the basal ganglia is reported. He was diagnosed as Down syndrome at birth. He had a tumor in the left basal ganglionic region at 12 years of the age. The tumor increased in size at age 14. He underwent cerebral angiography, which did not show a stenosis nor occlusion of the internal carotid artery, anterior cerebral artery, nor the middle cerebral artery. He received radiation therapy with a total dose of 56 Gy. He presented a dressing apraxia at age 19. MRI showed cerebral infarction in the left temporo-occipital region. Right internal carotid angiography revealed a severe stenosis of the internal carotid artery and anterior cerebral artery as well as a severe stenosis of the middle cerebral artery on the right side. Moyamoya-like vessels were seen in the basal ganglionic region. Left internal carotid angiography also showed a stenosis of the internal carotid artery and anterior cerebral artery as well as a severe stenosis of the middle cerebral artery on the left side. Moyamoya-like vessels were seen in the basal ganglionic region. Leptomeningeal anastomose and transdural anastomose were bilaterally seen. These arterial occlusion and stenotic phenomenon corresponded to a previous radiation field. These Moyamoya-like vessels with arterial stenosis and occlusion were thought to be due to radiation-induced vasculopathy, because a previous cerebral angiography showed a normal caliber of cerebral arteries. This patient showed that patients with radiation therapy in their early childhood should be carefully observed considering the possibility of the phenomenon. (author)

  19. Studies on intracranial collateral circulation with multi-slice CT angiography in patients with symptomatic cerebral artery stenosis

    Directory of Open Access Journals (Sweden)

    Shu-qing ZHOU

    2011-06-01

    Full Text Available Objective To explore the features of intracranial collateral circulation in patients with symptomatic cerebral artery stenosis.Method Ninety-four patients with ischemic cerebrovascular disease admitted from Apr.2004 to Jun.2009 were involved in present study.All the patients were examined with cerebral multi-slice CT angiography,and the features of cerebral artery stenosis and intracranial collateral circulation were evaluated using maximum intensity projection(MIP and volume rendering(VR images of CT angiography.Result Of the 94 patients involved,48 were diagnosed as cerebral artery stenosis,including 29 cases of cerebral infarction,18 of transient ischemic attack(TIA and 1 of moyamoya disease(MMD.Among the 14 cases of severe cerebral artery stenosis or occlusion,cerebral infarction was found in 6 cases with lesser intracranial collateral vessels(including massive cerebral infarction in 4 cases and watershed infarction in 2 cases,and focal infarction of central semi-ovale in 1 case and TIA in 7 cases were found with abundant intracranial collateral vessels.Multiple lacunar infarction was found in 22 cases of mild or moderate cerebral artery stenosis,but there was no significant correlation between the stenosed arteries and infarction sites.Abundant intracranial collateral vessels were found in one patient with Moyamoya disease but no infarction was observed.Conclusions Intracranial collateral circulation plays an important role of compensation in patients with severe cerebral artery stenosis or occlusion.Cerebral angiography with multi-slice CT is of great significance in evaluation of cerebral artery stenosis and intracranial collateral circulation.

  20. Neonatal Cerebral Sinovenous Thrombosis

    OpenAIRE

    J Gordon Millichap

    2006-01-01

    The presentation, treatment, and outcome of neonatal cerebral sinovenous thrombosis (SVT) were studied in 42 children, using neurology clinic records (1986-2005) at Indiana University School of Medicine.

  1. Cerebral Aneurysms Fact Sheet

    Science.gov (United States)

    ... cerebral aneurysm from forming. People with a diagnosed brain aneurysm should carefully control high blood pressure, stop smoking, and avoid cocaine use or other stimulant drugs. They should also ...

  2. Cerebral amyloid angiopathy

    Science.gov (United States)

    ... Fenichel GM, Jankovic J, Mazziotta JC, eds. Bradley's Neurology in Clinical Practice . 6th ed. Philadelphia, PA: Elsevier ... al. Course of cerebral amyloid angiopathy-related inflammation. Neurology. 2007;68:1411-1416. PMID: 17452586 www.ncbi. ...

  3. Acute ischemic cerebral attack

    OpenAIRE

    Franco-Garcia Samir; Barreiro-Pinto Belis

    2010-01-01

    The decrease of the cerebral blood flow below the threshold of autoregulation led to changes of cerebral ischemia and necrosis that traduce in signs and symtoms of focal neurologic dysfunction called acute cerebrovascular symdrome (ACS) or stroke. Two big groups according to its etiology are included in this category the hemorragic that constitue a 20% and the ischemic a 80% of cases. Great interest has wom the ischemic ACS because of its high social burden, being the third cause of no violen...

  4. Cerebral aneurysms and inflammation

    Directory of Open Access Journals (Sweden)

    Toshihiro Yokoi

    2015-06-01

    Full Text Available Multiple inflammatory factors, playing a crucial role in cerebral aneurysm formation, have been identified. tumor necrosis factor-alpha (TNF-α has been revealed to have a close connection with several risk factors that affect aneurysm formation. Remarkable expression in aneurysm walls of mRNA for TNF-α has been observed in humans. Possible therapeutic interventions to reduce the formation of cerebral aneurysms may include the inhibition of mediators of inflammation.

  5. Rehabilitation in cerebral palsy.

    OpenAIRE

    Molnar, G. E.

    1991-01-01

    Cerebral palsy is the most frequent physical disability of childhood onset. Over the past four decades, prevalence has remained remarkably constant at 2 to 3 per 1,000 live births in industrialized countries. In this article I concentrate on the rehabilitation and outcome of patients with cerebral palsy. The epidemiologic, pathogenetic, and diagnostic aspects are highlighted briefly as they pertain to the planning and implementation of the rehabilitation process.

  6. Cerebral Palsy Litigation

    OpenAIRE

    Sartwelle, Thomas P.; Johnston, James C.

    2015-01-01

    The cardinal driver of cerebral palsy litigation is electronic fetal monitoring, which has continued unabated for 40 years. Electronic fetal monitoring, however, is based on 19th-century childbirth myths, a virtually nonexistent scientific foundation, and has a false positive rate exceeding 99%. It has not affected the incidence of cerebral palsy. Electronic fetal monitoring has, however, increased the cesarian section rate, with the expected increase in mortality and morbidity risks to mothe...

  7. Low frequency oscillations in cephalic vessels assessed by near infrared spectroscopy

    DEFF Research Database (Denmark)

    Phillip, Dorte; Schytz, Henrik W; Selb, Juliette;

    2012-01-01

    BACKGROUND AND METHODS: Low frequency oscillations (LFO) of cerebral vessels are believed to reflect cerebral autoregulation. We investigated day-to-day and hemispheric variations in 0.1 Hz LFO with near infrared spectroscopy (NIRS) and transcranial Doppler (TCD) to determine phase shift and gain...... of oxygenated haemoglobin (oxyHb) and the velocity of the middle cerebral artery (Vmca) to the arterial blood pressure (ABP). The direct left-right phase shifts of oxyHb and Vmca were also assessed. We examined 44 healthy volunteers by simultaneous recordings of ABP, oxyHb and Vmca during spontaneous...

  8. Study on operation conditions and an operation system of a nuclear powered submersible research vessel, 'report of working group on application of a very small nuclear reactor to an ocean research'

    International Nuclear Information System (INIS)

    JAERI has studied on design of a nuclear powered submersible research vessel, which will navigate under sea mainly in the Arctic Ocean, as a part of the design activity of advanced marine reactors. This report describes operation conditions and an operating system of the vessel, which were discussed by the specialists of hull design, sound positioning, ship motions and oceanography, etc. The design conditions on ship motions for submersible vessels were surveyed considering regulations in our country, and ship motions were evaluated in the cases of underwater and surface navigations taking account of observation activities in the Arctic Ocean. The effect of ship motions on the compact nuclear reactor SCR was assessed. A submarine transponder system and an on-ice communication buoy system were examined as a positioning and communication system, supposing the activity under ice. The interval between transponders or communication buoys was recommended as 130 km. Procedures to secure safety of nuclear powered submersible research vessel were discussed according to accidents on the hull or the nuclear reactor. These results were reflected to the concept of the nuclear powered submersible research vessel, and subjects to be settled in the next step were clarified. (author)

  9. Study on operation conditions and an operation system of a nuclear powered submersible research vessel, 'report of working group on application of a very small nuclear reactor to an ocean research'

    Energy Technology Data Exchange (ETDEWEB)

    Ura, Tamaki [Tokyo Univ., Tokyo (Japan); Takamasa, Tomoji [Tokyo Univ. of Mercantile Marine, Tokyo (Japan); Nishimura, Hajime [Japan Marine Science and Technology Center, Yokosuka, Kanagawa (JP)] [and others

    2001-07-01

    JAERI has studied on design of a nuclear powered submersible research vessel, which will navigate under sea mainly in the Arctic Ocean, as a part of the design activity of advanced marine reactors. This report describes operation conditions and an operating system of the vessel, which were discussed by the specialists of hull design, sound positioning, ship motions and oceanography, etc. The design conditions on ship motions for submersible vessels were surveyed considering regulations in our country, and ship motions were evaluated in the cases of underwater and surface navigations taking account of observation activities in the Arctic Ocean. The effect of ship motions on the compact nuclear reactor SCR was assessed. A submarine transponder system and an on-ice communication buoy system were examined as a positioning and communication system, supposing the activity under ice. The interval between transponders or communication buoys was recommended as 130 km. Procedures to secure safety of nuclear powered submersible research vessel were discussed according to accidents on the hull or the nuclear reactor. These results were reflected to the concept of the nuclear powered submersible research vessel, and subjects to be settled in the next step were clarified. (author)

  10. Acute embolic cerebral ischemia as an initial presentation of polycythemia vera: a case report

    OpenAIRE

    Zoraster, Richard M; Rison, Richard A

    2013-01-01

    Introduction Patients with polycythemia vera are at high risk for vaso-occlusive events including cerebral ischemia. Although unusual, acute ischemic stroke may be an initial presentation of polycythemia vera. It had been previously assumed that cerebral ischemic events were due to increased blood viscosity and platelet activation within the central nervous system arterial vessels. However, there are now a few isolated case reports of probable micro-embolic events originating from outside of ...

  11. The effect of hyperglycemia on lipid peroxidation in the global cerebral ischemia of the rat.

    OpenAIRE

    Roh, J. K.; Hong, S B; Yoon, B. W.; Kim, M.S.; Myung, H.

    1992-01-01

    To investigate the influence of hyperglycemia on ischemic brain damage, we measured brain ATP, lactate and malondialdehyde (MDA) levels in global cerebral ischemic models of Wistar rats. We induced global cerebral ischemia by the 4-vessel occlusion method. After 30 or 60 min of occlusion, and after 30 min of reperfusion, we measured brain ATP, lactate and MDA levels. During the ischemic period, brain ATP levels decreased to 30-70% of sham groups both in normoglycemic and hyperglycemic groups....

  12. Early exercise improves cerebral blood flow through increased angiogenesis in experimental stroke rat model

    OpenAIRE

    Zhang, Pengyue; Yu, Huixian; Zhou, Naiyun; Jie ZHANG; Wu, Yi; Zhang, Yuling; Bai, Yulong; Jia, Jie; Zhang, Qi; Tian, Shan; Wu, Junfa; Hu, Yongshan

    2013-01-01

    Background Early exercise after stroke promoted angiogenesis and increased microvessles density. However, whether these newly formatted vessels indeed give rise to functional vascular and improve the cerebral blood flow (CBF) in impaired brain region is still unclear. The present study aimed to determine the effect of early exercise on angiogenesis and CBF in ischemic region. Methods Adult male Sprague Dawley rats were subjected to 90 min middle cerebral artery occlusion(MCAO)and randomly div...

  13. [Stent-assisted mechanical removal of tromboembolism after embolization of middle cerebral artery aneurysm].

    Science.gov (United States)

    Poncyljusz, Wojciech; Falkowski, Aleksander; Rać, Monika; Sagan, Leszek; Kojder, Ireneusz

    2012-01-01

    Thrombotic occlusion of the middle cerebral artery's branch occurred just after embolization of a nonruptured cerebral aneurysm. Bail-out stent-assisted mechanical thrombectomy of the clot was performed. DSA revealed normal vessel patency at the end of the procedure. There were no adverse events related to this thrombectomy, and the patient recovered from the embolization with minor neurologic deficit. There was no neurologic deficit after 90 days follow-up. PMID:23276015

  14. [The pathogenetic prerequisites for the application of the general magnetic therapy in the children presenting with cerebral ischemia].

    Science.gov (United States)

    Denisova, O I; Davydkin, N F; Kulikov, A G

    2014-01-01

    This article presents the analysis of the current literature and the original data of the authors providing the rationale for the use of magnetic therapy for the treatment of the children presenting with cerebral ischemia taking into consideration pathogenesis of this disease. It is demonstrated that the application of the general magnetic field decreases the tone of the cerebral vessels and improves blood flow to the brain which increases resistance to cerebral hypoxia. The results of investigations into the microcirculatory changes and liquor dynamics in conjunction with the ventriculometric measurements give evidence of the effectiveness of the combined treatment of cerebral ischemia making use of general magnetic therapy. PMID:25536760

  15. Diffuse brain calcification after radiation therapy in infantile cerebral malignant glioma

    International Nuclear Information System (INIS)

    We reported a case of infantile cerebral malignant glioma, which showed extensive intracranial calcification following radiation therapy, and reviewed the literature. A 4-month-old female infant was admitted to our hospital because of vomiting, enlargement of the head and convulsive seizures. Computerized tomography (CT) scans demonstrated a heterogeneously contrast-enhanced mass in the right temporo-parieto-occipital region and marked obstructive hydrocephalus. Subsequent to ventriculo-peritoneal shunt, biopsy was performed. The surgical specimen revealed anaplastic glioma. She then underwent whole brain irradiation with 1800 rads before subtotal removal and 3000 rads postoperatively. Calcification was first identified in the right frontal region and left basal ganglia 2.5 months after radiation therapy. At the age of 14 months, CT scans demonstrated extensive intracranial calcification in the cerebral hemispheres, basal ganglias, thalami, pons and cerebellum. A biopsy specimen of the frontal lobe revealed calcospherites of various sizes within and beside the walls of small vessels, but no tumor cells were observed. Cranial radiation therapy is a standard modality for treatment of children with neoplasm in the central nervous system. Since, however this therapy possibly causes long-term complications on the developing brain, it is important to plan radiation therapy for the brain tumor carefully. (author)

  16. Cerebral aspergillosis: comparison of radiological and neuropathologic findings in patients with bone marrow transplantation

    International Nuclear Information System (INIS)

    Thirty-six lesions in six patients who died from cerebral Aspergillus infection after bone marrow transplantation (BMT) were studied with regard to signal intensity, contrast enhancement, size, and location. The diagnosis was confirmed in all cases by autopsy. Retrospective correlation of histopathological and radiological findings was possible for 14 lesions. Most of the lesions (22/36) had isointense to low signal intensity on T2-weighted images (T2WI). Histopathologically, hemorrhagic necrosis was determined in three of them. Areas of high signal intensity on T1-weighted images (T1WI) were related to gross hemorrhage. Two infarctions showed intravascular accumulation of fungal hyphae with secondary thrombosis of the vessel. The remaining 12 lesions had high signal intensity on T2WI and low on T1WI. Histopathologically, four were infectious and four were unspecific demyelinated lesions. In conclusion, cerebral aspergillosis typically presented with large lesions showing isointense to low signal intensity on T2WI that could have areas of high signal on T1WI. Contrast enhancement was only visible in 15 lesions, and the predominant locations were the subcortical white matter, the cerebellum, and the basal ganglia. Small lesions with high signal on T2WI and low signal on T1WI could not necessarily be related to Aspergillus infection. (orig.)

  17. In vivo microCT imaging of rodent cerebral vasculature

    International Nuclear Information System (INIS)

    Computed tomography (CT) remains a critical diagnostic tool for evaluating patients with cerebrovascular disease, and the advent of specialized systems for imaging rodents has extended these techniques to small animal models of these diseases. We therefore have evaluated in vivo methods of imaging rat models of hemorrhagic stroke using a high resolution compact computed tomography ('microCT') system (FLEX(tm) X-O(tm), Gamma Medica-Ideas, Northridge, CA). For all in vivo studies, the head of the anesthetized rat was secured in a custom immobilization device for microCT imaging with 512 projections over 2 min at 60 kVp and 0.530 mA (Itube x t/rotation = 63.6 mAs). First, imaging without iodinated contrast was performed (a) to differentiate the effect of contrast agent in contrast-enhanced CT and (b) to examine the effectiveness of the immobilization device between two time points of CT acquisitions. Then, contrast-enhanced CT was performed with continuous administration of iopromide (300 mgI ml-1 at 1.2 ml min-1) to visualize aneurysms and other vascular formations in the carotid and cerebral arteries that may precede subarachnoid hemorrhage. The accuracy of registration between the noncontrast and contrast-enhanced CT images with the immobilization device was compared against the images aligned with normalized mutual information using FMRIB's linear image registration tool (FLIRT). Translations and rotations were examined between the FLIRT-aligned noncontrast CT image and the nonaligned noncontrast CT image. These two data sets demonstrated translational and rotational differences of less than 0.5 voxel (∼85 μm) and 0.5 deg., respectively. Noncontrast CT demonstrated a very small volume (0.1 ml) of femoral arterial blood introduced surgically into the rodent brain. Continuous administration of iopromide during the CT acquisition produced consistent vascular contrast in the reconstructed CT images. As a result, carotid arteries and major cerebral blood vessels

  18. In vivo microCT imaging of rodent cerebral vasculature

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Youngho; Hasegawa, Bruce H [Center for Molecular and Functional Imaging, Department of Radiology, University of California, San Francisco, CA 94143 (United States); Hashimoto, Tomoki; Nuki, Yoshitsugu [Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA 94143 (United States)], E-mail: youngho.seo@radiology.ucsf.edu

    2008-04-07

    arteries and major cerebral blood vessels were visible with contrast-enhanced CT, but not with noncontrast CT. In conclusion, the CT-compatible immobilization device was useful for in vivo microCT imaging of intracranial blood and of vascular structures within and immediately adjacent to the rodent brain. The microCT imaging technique is also compatible with continuous administration of a conventional iodinated contrast agent (e.g. iopromide) and therefore does not require specialized small animal specific contrast agent that has comparatively long in vivo residence time. (note)

  19. Numerical analysis of hemodynamics in spastic middle cerebral arteries.

    Science.gov (United States)

    Wen, Jun; Wang, Qingfeng; Wang, Qingyuan; Khoshmanesh, Khashayar; Zheng, Tinghui

    2016-11-01

    Cerebral vasospasm (CVS) is the most common serious complication of subarachnoid hemorrhage. Among the many factors that are associated with the pathogenesis of CVS, hemodynamics plays an important role in the initiation and development of CVS. Numerical simulation was carried out to obtain the flow patterns and wall shear stress (WSS) distribution in spastic middle cerebral arteries. The blood was assumed to be incompressible, laminar, homogenous, Newtonian, and steady. Our simulations reveal that flow velocity and WSS level increase at the stenosis segment of the spastic vessels, but further downstream of stenosis, the WSS significantly decreases along the inner wall, and flow circulation and stagnation are observed. The hydrodynamic resistance increases with the increase of vessel spasm. Moreover, the change of flow field and hydrodynamic forces are not linearly proportional to the spasm level, and the rapid change of hemodynamic parameters is observed as the spasm is more than 50%. Accordingly, in the view of hemodynamic physiology, vessels with less than 30% stenosis are capable of self-restoration towards normal conditions. However, vessels with more than 50% stenosis may eventually lose their capacity to adapt to differing physiologic conditions due to the extreme non-physilogic hemodynamic environment, and the immediate expansion of the vessel lumen might be needed to minimize serious and non-reversible effects. PMID:26942314

  20. Effects of parent vessel geometry on intraaneurysmal flow patterns

    Science.gov (United States)

    Castro, Marcelo A.; Putman, Christopher M.; Cebral, Juan R.

    2006-03-01

    This study shows the influence of the upstream parent artery geometry on intra-aneurysmal hemodynamics of cerebral aneurysms. Patient-specific models of four cerebral aneurysms at four typical locations were constructed from 3D rotational angiography images. Two geometrical models were constructed for each patient, one with the native parent vessel geometry and another with the parent vessel truncated approximately 1cm upstream from the aneurysm. For one aneurysm, two images were used to construct a model as realistic and large as possible - down to the carotid bifurcation - which was cut at seven different locations. Corresponding finite element grids were generated and computational fluid dynamics simulations were carried out under pulsatile flow conditions. It was found that truncated models tended to underestimate the wall shear stress in the aneurysm and to shift the impaction zone to the neck when compared with the native geometry. In one aneurysm the parent vessel included a tortuous segment close to the neck that strongly influenced the flow pattern entering the aneurysm. Thus, including longer portions of the parent vessel beyond this segment did not have a substantial effect. Depending on the dominant geometrical features the length of the parent artery needed for an accurate representation of the intraaneurysmal hemodynamics may vary among individuals. In conclusion, failure to properly model the inflow stream determined by the upstream parent artery can significantly influence the results of intra-aneurysmal hemodynamic models. The upstream portion of the parent vessel of cerebral aneurysms should be included in order to accurately represent the intraaneurysmal hemodynamics.

  1. Cerebral circulation and metabolism in cerebral infarction of middle cerebral artery territory

    International Nuclear Information System (INIS)

    Regional cerebral blood flow (rCBF), oxygen metabolism (rCMRO2), oxygen extraction fraction (rOEF) and blood volume (rCBV) were measured with a high performance positron CT (HEADTOME-III) and the 15O labeled gas steady-state method. Seven normal volunteers and 13 patients with ischemic infarction located in the territory of unilateral middle cerebral artery (MCA) were subjected to the positron CT measurement. In the present study, over estimation of rOEF and rCMRO2 were corrected by rCBV using the principle described by Lammertsma and Jones. From these paremeters we also calculated an rCBV/rCBF which meant regional blood transient time of cerebral vessels (rTT). Early ischemic lesions showed two types of uncoupling between rCBF and rCMRO2. Patients studied within the 5th day of the onset showed high rOEF with low rCBF in the infarcted forcus (misery perfusion). About a week after onset rOEF was changed into low level with decreased rCMRO2 and recovered rCBF, and the change lasted to a month after onset recovered rCBF, and the change lasted to a month after onset (luxury perfusion). Then, about two months later, the lesions gradually went to matched change of rCBF and rCMRO2 (coupled perfusion). These changes of rCBF and rCMRO2 described above will reveal the natural course of ischemic brain tissue with acute onset. It was also proved that there was positive correlation between rTT and rOEF. A parameter of rTT will be important to presume rOEF from a single photon emission CT measurement, which has not been able to study oxygen metabolism but could measure rCBF and rCBV. The threshold levels of rCBF and rCMRO2 for morphological tissue damages assessed as a low density area on a X-ray CT were clinically estimated from the present study. The thresholds evaluated in patients within a day of onset, were 12 ml/100 ml/min, and 1.5 ml/ 100 ml/min for rCBF and rCMRO2, respectively. (J.P.N.)

  2. 2013 Tanker Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  3. Cheboygan Vessel Base

    Data.gov (United States)

    Federal Laboratory Consortium — Cheboygan Vessel Base (CVB), located in Cheboygan, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). CVB was established by congressional...

  4. 2013 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  5. 2011 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  6. 2013 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  7. 2013 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  8. 2011 Passenger Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  9. High Performance Marine Vessels

    CERN Document Server

    Yun, Liang

    2012-01-01

    High Performance Marine Vessels (HPMVs) range from the Fast Ferries to the latest high speed Navy Craft, including competition power boats and hydroplanes, hydrofoils, hovercraft, catamarans and other multi-hull craft. High Performance Marine Vessels covers the main concepts of HPMVs and discusses historical background, design features, services that have been successful and not so successful, and some sample data of the range of HPMVs to date. Included is a comparison of all HPMVs craft and the differences between them and descriptions of performance (hydrodynamics and aerodynamics). Readers will find a comprehensive overview of the design, development and building of HPMVs. In summary, this book: Focuses on technology at the aero-marine interface Covers the full range of high performance marine vessel concepts Explains the historical development of various HPMVs Discusses ferries, racing and pleasure craft, as well as utility and military missions High Performance Marine Vessels is an ideal book for student...

  10. Maury Journals - US Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  11. Coastal Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels that have been issued a Federal permit for the Gulf of Mexico reef fish,...

  12. 2011 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  13. Contractile 5-HT1B receptors in human cerebral arteries

    DEFF Research Database (Denmark)

    Nilsson, T; Longmore, J; Shaw, D;

    1999-01-01

    immunocytochemistry with antibodies selective for human 5-HT1B and human 5-HT1D receptors and also studied the contractile effects of a range of 5-HT receptor agonists and antagonists in HCA. 2 Immunocytochemistry of cerebral arteries showed dense 5-HT1B receptor immunoreactivity (but no 5-HT1D receptor......1 The cerebrovascular receptor(s) that mediates 5-hydroxytryptamine (5-HT)-induced vasoconstriction in human cerebral arteries (HCA)has proven difficult to characterize, yet these are essential in migraine. We have examined 5-HT receptor subtype distribution in cerebral blood vessels by...... immunoreactivity) within the smooth muscle wall of the HCA. The endothelial cell layer was well preserved and weak 5-HT1B receptor immunoreactivity was present. 3 Pharmacological experiments on HCA with intact endothelium showed that 5-carboxamidotryptamine was significantly more potent than alpha-methyl-5-HT, 2...

  14. Holographic demonstration of cerebral vascular and microvascular topography

    International Nuclear Information System (INIS)

    The topographic anatomy of the cerebral arterial distribution system is illustrated in three dimensions by holographic displays. Each display was prepared by injecting the internal and external carotid arteries of four excised human brains with polymer material that hardens within the arteries. The polymer material suspends particulates having high x-ray absorption so that 100-μm vessels can be distinguished. A laboratory digital radiography system was used to acquire high-fidelity digital radiographs from points of view separated by 10. The exhibit presents an educationally useful format for learning whole-brain cerebral topography and a scientifically new method (microradiographic holography) for studying cerebral microvasculature in selected regions. Anatomic knowledge from these studies will aid the planning of microsurgery and aneurysm surgery

  15. Personal peculiarities in patients with middle cerebral artery infarction

    Directory of Open Access Journals (Sweden)

    Antonova N.A.

    2013-12-01

    Full Text Available The purpose of the work is to reveal personal peculiarities in patients who have suffered middle cerebral artery infarction. Material and Methods. 39 patients with middle cerebral artery infarction have been under the study. All patients have received clinical instrumental inspection (neurologic survey, duplex ultrasound investigation of vessels of neck, head and brain, the research CT or MRT. Personal peculiarities have been studied by "The standard multiple-factor method of research of the personality" (PITCHES. Results. Psychological reactions for the disease have been determined. They include hypochondria, depression, psychasthenia and anxiety. Conclusion. Personal peculiarities in patients suffered from middle cerebral artery infarction may be characterized by the appearance of psychological response to the psychotraumatic situation. Therefore it is necessary to give psychotherapeutic aid.

  16. Holographic and acoustic emission evaluation of pressure vessels

    International Nuclear Information System (INIS)

    Optical holographic interfereometry and acoustic emission monitoring were simultaneously used to evaluate two small, high pressure vessels during pressurization. The techniques provide pressure vessel designers with both quantitative information such as displacement/strain measurements and qualitative information such as flaw detection. The data from the holographic interferograms were analyzed for strain profiles. The acoustic emission signals were monitored for crack growth and vessel quality

  17. Nanomedicine in cerebral palsy

    Directory of Open Access Journals (Sweden)

    Balakrishnan B

    2013-11-01

    Full Text Available Bindu Balakrishnan,1 Elizabeth Nance,1 Michael V Johnston,2 Rangaramanujam Kannan,3 Sujatha Kannan1 1Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University; Baltimore, MD, USA; 2Department of Neurology and Pediatrics, Kennedy Krieger Institute, Baltimore, MD, USA; 3Department of Ophthalmology, Center for Nanomedicine, Johns Hopkins University, Baltimore, MD, USA Abstract: Cerebral palsy is a chronic childhood disorder that can have diverse etiologies. Injury to the developing brain that occurs either in utero or soon after birth can result in the motor, sensory, and cognitive deficits seen in cerebral palsy. Although the etiologies for cerebral palsy are variable, neuroinflammation plays a key role in the pathophysiology of the brain injury irrespective of the etiology. Currently, there is no effective cure for cerebral palsy. Nanomedicine offers a new frontier in the development of therapies for prevention and treatment of brain injury resulting in cerebral palsy. Nanomaterials such as dendrimers provide opportunities for the targeted delivery of multiple drugs that can mitigate several pathways involved in injury and can be delivered specifically to the cells that are responsible for neuroinflammation and injury. These materials also offer the opportunity to deliver agents that would promote repair and regeneration in the brain, resulting not only in attenuation of injury, but also enabling normal growth. In this review, the current advances in nanotechnology for treatment of brain injury are discussed with specific relevance to cerebral palsy. Future directions that would facilitate clinical translation in neonates and children are also addressed. Keywords: dendrimer, cerebral palsy, neuroinflammation, nanoparticle, neonatal brain injury, G4OH-PAMAM

  18. Corkscrew angiopathy of intracranial vessels in a young stroke patient: a case report

    OpenAIRE

    Alurkar Anand; Karanam Lakshmi Sudha P; Oak Sagar P

    2012-01-01

    Abstract Introduction We present a rare finding of a ‘corkscrew appearance’ of the distal cerebral vessels in a young Asian woman who presented with acute stroke. Case presentation A 32-year-old Asian woman presented with a 3-month history of recurrent right-sided transient ischemic attacks. Her clinical workup and brain imaging results were normal. A digital subtraction angiogram revealed an abnormal corkscrew appearance of all intracranial distal vessels. She was discharged on a single anti...

  19. LANL Robotic Vessel Scanning

    Energy Technology Data Exchange (ETDEWEB)

    Webber, Nels W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-25

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.The project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.

  20. An Active Contour Model Based on Adaptive Threshold for Extraction of Cerebral Vascular Structures

    Science.gov (United States)

    Wang, Jiaxin; Zhao, Shifeng; Liu, Zifeng; Duan, Fuqing; Pan, Yutong

    2016-01-01

    Cerebral vessel segmentation is essential and helpful for the clinical diagnosis and the related research. However, automatic segmentation of brain vessels remains challenging because of the variable vessel shape and high complex of vessel geometry. This study proposes a new active contour model (ACM) implemented by the level-set method for segmenting vessels from TOF-MRA data. The energy function of the new model, combining both region intensity and boundary information, is composed of two region terms, one boundary term and one penalty term. The global threshold representing the lower gray boundary of the target object by maximum intensity projection (MIP) is defined in the first-region term, and it is used to guide the segmentation of the thick vessels. In the second term, a dynamic intensity threshold is employed to extract the tiny vessels. The boundary term is used to drive the contours to evolve towards the boundaries with high gradients. The penalty term is used to avoid reinitialization of the level-set function. Experimental results on 10 clinical brain data sets demonstrate that our method is not only able to achieve better Dice Similarity Coefficient than the global threshold based method and localized hybrid level-set method but also able to extract whole cerebral vessel trees, including the thin vessels. PMID:27597878

  1. An Active Contour Model Based on Adaptive Threshold for Extraction of Cerebral Vascular Structures.

    Science.gov (United States)

    Wang, Jiaxin; Zhao, Shifeng; Liu, Zifeng; Tian, Yun; Duan, Fuqing; Pan, Yutong

    2016-01-01

    Cerebral vessel segmentation is essential and helpful for the clinical diagnosis and the related research. However, automatic segmentation of brain vessels remains challenging because of the variable vessel shape and high complex of vessel geometry. This study proposes a new active contour model (ACM) implemented by the level-set method for segmenting vessels from TOF-MRA data. The energy function of the new model, combining both region intensity and boundary information, is composed of two region terms, one boundary term and one penalty term. The global threshold representing the lower gray boundary of the target object by maximum intensity projection (MIP) is defined in the first-region term, and it is used to guide the segmentation of the thick vessels. In the second term, a dynamic intensity threshold is employed to extract the tiny vessels. The boundary term is used to drive the contours to evolve towards the boundaries with high gradients. The penalty term is used to avoid reinitialization of the level-set function. Experimental results on 10 clinical brain data sets demonstrate that our method is not only able to achieve better Dice Similarity Coefficient than the global threshold based method and localized hybrid level-set method but also able to extract whole cerebral vessel trees, including the thin vessels. PMID:27597878

  2. A clinical study of acute cerebral infarction with a midline shift on the CT scan

    International Nuclear Information System (INIS)

    Twenty-one cases of acute cerebral infarction with a midline shift on the CT scan were studied with respect to the development of the midline shift, the angiographic findings, the clinical pictures and the outcome of these patients. The CT findings of hemorrhagic infarction were also studied. No cases showed a midline shift on a CT scan taken within 6 hours after the onset. A midline shift was, however, noted as early as 9 hours after the onset, and it reached its peak between the 2nd and 7th day of the onset. It gradually disappeared by the end of the third week. Hemorrhagic infarction was diagnosed in 6 patients by either spinal tap or autopsy. The CT findings of these hemorrhagic infarction were divided into two types, solid hemorrhages with an unequivocal high density within the low-density area, and small, scattered hemorrhagic of almost the same density as normal brain tissue within the low-density area. In 19 of 21 patients, an round-edged occlusion and/or embolus were observed on the initial angiograms. The recanalization of the occluded vessels was proved in 10 of 14 patients by subsequent angiographic studies. Twenty of 21 patients showed a sudden development of neurological symptoms, and 15 patients had a history of various kinds of heart disease, such as atrial fibrillation, valvular heart disease and myocardial infarction. The patients had atrial fibrillation on EKG on admission. These angiographic findings and clinical pictures strongly suggest that the infarction with a midline shift on the CT scan may be caused by a cerebral embolism of cardiac origin. Eight patients died of cerebral herniation between the 2nd and 6th day of the onset. Taking these poor outcomes into consideration, surgical as well as medical decompression of the brain would seem to be most important when the CT scan shows a midline shift. (author)

  3. Clinical Neuroimaging of cerebral ischemia

    International Nuclear Information System (INIS)

    Notice points in clinical imaging of cerebral ischemia are reviewed. When cerebral blood flow is determined in acute stage of cerebral embolism (cerebral blood flow SPECT), it is important to find area of ischemic core and ischemic penumbra. When large cortex area is assigned to ischemic penumbra, thrombolytic therapy is positively adapted, but cautious correspondence is necessary when ischemic core is recognized. DWI is superior in the detection of area equivalent to ischemic core of early stage, but, in imaging of area equivalent to ischemic penumbra, perfusion image or distribution image of cerebral blood volume (CBV) by MRI need to be combined. Luxury perfusion detected by cerebral blood flow SPECT in the cases of acute cerebral embolism suggests vascular recanalization, but a comparison with CT/MRI and continuous assessment of cerebral circulation dynamics were necessary in order to predict brain tissue disease (metabolic abnormality). In hemodynamic cerebral ischemia, it is important to find stage 2 equivalent to misery perfusion by quantification of cerebral blood flow SPECT. Degree of diaschisis can indicate seriousness of brain dysfunction for lacuna infarct. Because cerebral circulation reserve ability (perfusion pressure) is normal in all areas of the low cerebral blood flow by diaschisis mechanism, their areas are easily distinguished from those of hemodynamic cerebral ischemia. (K.H.)

  4. THE EFFECT OF LIGUSTRAZINE ON NEUROGENESIS IN CORTEX AFTER FOCAL CEREBRAL ISCHEMIA IN RATS

    Institute of Scientific and Technical Information of China (English)

    邱芬; 刘勇; 张蓬勃; 康前雁; 田英芳; 陈新林; 赵建军; 祁存芳

    2006-01-01

    It has been demonstrated that there are neuralstemcells that can self-renewand differentiate intomultiple cell types[1-3]in central nervous system ofadult mammals.After cerebral ischemia,these cellscan proliferate,migrate,differentiate and partici-pate in the repair of ischemic cerebral injuries[4-6].Neural stemcells play a very i mportant role in alle-viating ischemic cerebral injuries and promotingfunctional recovery.Ligustrazine,an active ingre-dient of Ligustici,can help dilate blood vessels,i m-prove m...

  5. Successful repair of a syphilitic aortic arch aneurysm accompanied by serious cerebral infarction.

    Science.gov (United States)

    Sato, Katsutoshi; Chiba, Kiyoshi; Koizumi, Nobusato; Ogino, Hitoshi

    2014-01-01

    We present a 52-year-old male with a syphilitic aortic arch aneurysm accompanied by relevant extensive cerebral infarction. He was admitted to a local hospital for sudden loss of consciousness, where he was diagnosed with serious cerebral infarction. During his treatment, a multilocular aortic arch aneurysm involving the arch vessels was found incidentally. He was transferred to our hospital for surgical treatment. A preoperative routine laboratory test for syphilis was highly positive, which suggested that the aneurysm was likely caused by syphilis and the cerebral infarction was also induced by the involvement of syphilitic aortitis or arteritis. After 2 weeks of antibiotic therapy for syphilis, total arch replacement was performed successfully using meticulous brain protection with antegrade selective cerebral perfusion and deep hypothermia. He recovered without any further cerebral deficits. The pathological examination of the surgical specimen showed some characteristic changes of syphilitic aortitis. PMID:24492165

  6. Normal cerebral FDG uptake during childhood

    Energy Technology Data Exchange (ETDEWEB)

    London, Kevin [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Discipline of Paediatrics and Child Health, Sydney Medical School, Sydney, NSW (Australia); Howman-Giles, Robert [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Disciplines of Imaging and Paediatrics and Child Health, Sydney Medical School, Sydney, NSW (Australia)

    2014-04-15

    Current understanding of cerebral FDG uptake during childhood originates from a small number of studies in patients with neurological abnormalities. Our aim was to describe cerebral FDG uptake in a dataset of FDG PET scans in children more likely to represent a normal population. We reviewed cerebral FDG PET scans in children up to 16 years of age with suspected/proven extracranial malignancies and the following exclusions: central nervous system metastases, previous malignancies, previous chemotherapy or radiotherapy, development of cerebral metastases during therapy, neurological conditions, taking antiepileptic medication or medications likely to interfere with cerebral metabolism, and general anaesthesia within 24 h. White matter, basal ganglia, thalamus and the cerebellar cortex were analysed using regional SUV{sub max}, and the cerebral cortex, basal ganglia, thalamus and cerebellum were analysed using a regional relative uptake analysis in comparison to maximal cortical uptake. Scans from 30 patients (age range 11 months to 16 years, mean age 10 years 5 months) were included. All regions showed increasing SUV{sub max} with age. The parietal, occipital, lateral temporal and medial temporal lobes showed lower rates of increasing FDG uptake causing changing patterns of regional FDG uptake during childhood. The cortical regions showing the most intense uptake in early childhood were the parietal and occipital lobes. At approximately 7 years of age these regions had relatively less uptake than the frontal lobes and at approximately 10 years of age these regions had relatively less uptake than the thalamus. Relative FDG uptake in the brain has not reached an adult pattern by 1 year of age, but continues to change up to 16 years of age. The changing pattern is due to different regional rates of increasing cortical FDG uptake, which is less rapid in the parietal, occipital and temporal lobes than in the frontal lobes. (orig.)

  7. Normal cerebral FDG uptake during childhood

    International Nuclear Information System (INIS)

    Current understanding of cerebral FDG uptake during childhood originates from a small number of studies in patients with neurological abnormalities. Our aim was to describe cerebral FDG uptake in a dataset of FDG PET scans in children more likely to represent a normal population. We reviewed cerebral FDG PET scans in children up to 16 years of age with suspected/proven extracranial malignancies and the following exclusions: central nervous system metastases, previous malignancies, previous chemotherapy or radiotherapy, development of cerebral metastases during therapy, neurological conditions, taking antiepileptic medication or medications likely to interfere with cerebral metabolism, and general anaesthesia within 24 h. White matter, basal ganglia, thalamus and the cerebellar cortex were analysed using regional SUVmax, and the cerebral cortex, basal ganglia, thalamus and cerebellum were analysed using a regional relative uptake analysis in comparison to maximal cortical uptake. Scans from 30 patients (age range 11 months to 16 years, mean age 10 years 5 months) were included. All regions showed increasing SUVmax with age. The parietal, occipital, lateral temporal and medial temporal lobes showed lower rates of increasing FDG uptake causing changing patterns of regional FDG uptake during childhood. The cortical regions showing the most intense uptake in early childhood were the parietal and occipital lobes. At approximately 7 years of age these regions had relatively less uptake than the frontal lobes and at approximately 10 years of age these regions had relatively less uptake than the thalamus. Relative FDG uptake in the brain has not reached an adult pattern by 1 year of age, but continues to change up to 16 years of age. The changing pattern is due to different regional rates of increasing cortical FDG uptake, which is less rapid in the parietal, occipital and temporal lobes than in the frontal lobes. (orig.)

  8. Effect of Electroacupuncture on Expression of p53 Protein in Cerebral Cortex of Rats with Global Cerebral Ischemia/Reperfusion Injury

    Institute of Scientific and Technical Information of China (English)

    卜渊; 耿德勤; 葛巍; 徐兴顺; 曾因明

    2004-01-01

    Objective: To observe the effect of electroacupuncture (EA) on expression of p53 protein in cerebral cortex of senile rats with global cerebral ischemia/reperfusion (IR) injury and to explore its mechanism. Methods: The cerebral IR injury rat model was established referring to Pulsinelli 4-vessel occlusion method. Thirty-six SD rats were randomly and evenly divided into the control group, the IR group and the IR plus EA (IR-EA) group. The animals in the control group were subjected to electrocauterization of vertebral arteries in bilateral flank orifice alone with the general carotid arteries unoccluded.To rats in the IR-EA group, immediately and 24h, 48h, 72h after cerebral IR, EA treatment on bilateral acupoint "Zusanli"(ST36) was applied once a day, lasting for 60 minutes. After the final treatment, all the rats were sacrificed and their brains were taken to examine p53 protein expression by the immunohistochemical method. Results: Cells with positive p53 immunoreactivity in the cerebral cortex of rats in the IR group was significantly higher than that in the control group ( P<0.05), while that in the IR-EA group was significantly lower than that in the IR group (P<0.05). Conclusion: EA could remarkably reduce expression of p53 protein in the cerebral cortex of senile rats with global cerebral IR injury, which might be one of the means for EA to inhibit neuronal apoptosis after cerebral IR injury.

  9. Cerebral CT of ischaemic lesions

    Energy Technology Data Exchange (ETDEWEB)

    Aulich, A.

    1981-11-25

    The diagnosis of stroke must first be established by clinical examination. CT has proved useful for confirmation of the diagnosis and provides a global intracranial picture of morphological changes in cerebral vascular diseases. A hemorrhage can be recognized with certainty at the first CT examination as the cause of the stroke, but in the detection of a lesion due to ischemia an important role is played by the correct choice of the time of examination, and in some cases also of the check-up with contrast medium. The differential diagnosis between infarct in the acute stage and encephalitis or gliomas of low-grade malignity can be difficult. A decision can often only be made after a series of examinations. Postmalacial conditions are often difficult to differentiate from defects due to other causes, such as hemorrhage, head injury, postoperative states and after encephalitis. A knowledge of the anamnesis and the clinical findings is indispensable for CT evaluation. In assessing the prognosis before vascular surgery on the extracranial brain-supplying vessels the performance of a CT examination should be advised. A warning is given against the use of CT as a screening method.

  10. Association between changes in weight and cerebral arteries in rats.

    Science.gov (United States)

    Divani, Afshin A; Patel, Ankur; Fredrickson, Vance L; Siljander, Blake; Vazquez, Gabriela

    2010-06-01

    The objective of the study was to gain a better understanding of brain artery diameters and anatomical variations for precise modification of cerebral blood supply in ischemic stroke models. Sprague-Dawley rats (n = 35) were used for the experiment. Rats were perfused and resin replicas of cerebral arteries were created using a corrosion casting technique. Resin replicas were measured and analyzed for correlation of vessel lumen with animal sex and weight. A strong correlation between root of aorta diameter and weight was observed (p < 0.0001). We also observed a significant correlation between weight, internal carotid arteries, right external carotid artery, and pterygopalatine arteries. For the common carotid artery, a significant difference between the left and right branches was observed even though there was no association with weight. There was no significant association observed between animal sex and vessel size independent of weight. A better knowledge of vessel lumen in relation to animal sex and weight is essential for adequate blockage of an intracranial artery to induce cerebral ischemia in a rat model of stroke. This study provides a viable reference for choice of rat size in relation to the size of embolic agents such as filaments, microwires, or in vitro thrombus used in ischemic stroke experiments. PMID:24323492

  11. Multilayer Composite Pressure Vessels

    Science.gov (United States)

    DeLay, Tom

    2005-01-01

    A method has been devised to enable the fabrication of lightweight pressure vessels from multilayer composite materials. This method is related to, but not the same as, the method described in gMaking a Metal- Lined Composite-Overwrapped Pressure Vessel h (MFS-31814), NASA Tech Briefs, Vol. 29, No. 3 (March 2005), page 59. The method is flexible in that it poses no major impediment to changes in tank design and is applicable to a wide range of tank sizes. The figure depicts a finished tank fabricated by this method, showing layers added at various stages of the fabrication process. In the first step of the process, a mandrel that defines the size and shape of the interior of the tank is machined from a polyurethane foam or other suitable lightweight tooling material. The mandrel is outfitted with metallic end fittings on a shaft. Each end fitting includes an outer flange that has a small step to accommodate a thin layer of graphite/epoxy or other suitable composite material. The outer surface of the mandrel (but not the fittings) is covered with a suitable release material. The composite material is filament- wound so as to cover the entire surface of the mandrel from the step on one end fitting to the step on the other end fitting. The composite material is then cured in place. The entire workpiece is cut in half in a plane perpendicular to the axis of symmetry at its mid-length point, yielding two composite-material half shells, each containing half of the foam mandrel. The halves of the mandrel are removed from within the composite shells, then the shells are reassembled and bonded together with a belly band of cured composite material. The resulting composite shell becomes a mandrel for the subsequent steps of the fabrication process and remains inside the final tank. The outer surface of the composite shell is covered with a layer of material designed to be impermeable by the pressurized fluid to be contained in the tank. A second step on the outer flange of

  12. The role of SDF-1/CXCR4 in the vasculogenesis and remodeling of cerebral arteriovenous malformation

    Directory of Open Access Journals (Sweden)

    Wang L

    2015-09-01

    Full Text Available Lingyan Wang,1 Shaolei Guo,2 Nu Zhang,2 Yuqian Tao,3 Heng Zhang,1 Tiewei Qi,2 Feng Liang,2 Zhengsong Huang2 1Department of Neurosurgery ICU, 2Department of Neurosurgery, 3Department of Neurology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, People’s Republic of China Background: Cerebral arteriovenous malformation (AVM involves the vasculogenesis of cerebral blood vessels and can cause severe intracranial hemorrhage. Stromal cell-derived factor-1 (SDF-1 and its receptor, CXCR4, are believed to exert multiple physiological functions including angiogenesis. Thus, we investigated the role of SDF-1/CXCR4 in the vasculogenesis of cerebral AVM.Methods: Brain AVM lesions from surgical resections were analyzed for the expression of SDF-1, CXCR4, VEGF-A, and HIF-1 by using immunohistochemical staining. Flow cytometry was used to quantify the level of circulating endothelial progenitor cells (EPCs. Further, in an animal study, chronic cerebral hypoperfusion model rats were analyzed for the expression of SDF-1 and HIF-1. CXCR4 antagonist, AMD3100, was also used to detect its effects on cerebral vasculogenesis and SDF-1 expression.Results: Large amounts of CXCR4-positive CD45+ cells were found in brain AVM lesion blood vessel walls, which also have higher SDF-1 expression. Cerebral AVM patients also had higher level of EPCs and SDF-1. In chronic cerebral hypoperfusion rats, SDF-1, HIF-1, and CD45 expressions were elevated. The application of AMD3100 effectively suppressed angiogenesis and infiltration of CXCR4-positive CD45+ cells in hypoperfusion rats compared to controls.Conclusion: The SDF-1/CXCR4 axis plays an important role in the vasculogenesis and migration of inflammatory cells in cerebral AVM lesions, possibly via the recruitment of bone marrow EPCs. Keywords: cerebral arteriovenous malformation, SDF-1/CXCR4, chronic cerebral hypoperfusion, endothelial progenitor cells

  13. 46 CFR 177.115 - Applicability to existing vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Applicability to existing vessels. 177.115 Section 177.115 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) CONSTRUCTION AND ARRANGEMENT General Provisions § 177.115 Applicability to...

  14. 46 CFR 178.420 - Drainage of cockpit vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of cockpit vessels. 178.420 Section 178.420 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS... clearing of water in all probable conditions of list and trim; (2) Have a combined drainage area of...

  15. Cerebral palsy and multiple births.

    OpenAIRE

    Pharoah, P. O.; Cooke, T

    1996-01-01

    AIM: To compare the birthweight specific prevalence of cerebral palsy in singleton and multiple births. METHODS: Registered births of babies with cerebral palsy born to mothers resident in the counties of Merseyside and Cheshire during the period 1982 to 1989 were ascertained. RESULTS: The crude prevalence of cerebral palsy was 2.3 per 1000 infant survivors in singletons, 12.6 in twins, and 44.8 in triplets. The prevalence of cerebral palsy rose with decreasing birthweight. The birthweight sp...

  16. Experimental Focal Cerebral Ischemia

    DEFF Research Database (Denmark)

    Christensen, Thomas

    2007-01-01

    Focal cerebral ischemia due to occlusion of a major cerebral artery is the cause of ischemic stroke which is a major reason of mortality, morbidity and disability in the populations of the developed countries. In the seven studies summarized in the thesis focal ischemia in rats induced by occlusion...... of the middle cerebral artery (MCAO) was used as an experimental model of ischemic stroke. MCAO produces an acute lesion consisting of an ischemic core or focus with severely reduced blood flow surrounded by a borderzone or ischemic penumbra with less pronounced blood flow reduction. Cells in the...... radical scavenger α-PBN on the periinfarct depolarizations and infarct volume was investigated. In study number six, the activity of the mitochondrial electron transport complexes I, II and IV was evaluated histochemically during reperfusion after MCAO in order to assess the possible role of mitochondrial...

  17. Cerebral hemodynamics in migraine

    DEFF Research Database (Denmark)

    Hachinski, V C; Olesen, Jes; Norris, J W;

    1977-01-01

    Clinical and angiographic findings in migraine are briefly reviewed in relation to cerebral hemodynamic changes shown by regional cerebral blood flow (rCBF) studies. Three cases of migraine studied by the intracarotid xenon 133 method during attacks are reported. In classic migraine, with typical...... prodromal symptoms, a decrease in cerebral blood flow has been demonstrated during the aura. Occasionally, this flow decrease persists during the headache phase. In common migraine, where such prodromata are not seen, a flow decrease has not been demonstrated. During the headache phase of both types of...... migraine, rCBF has usually been found to be normal or in the high range of normal values. The high values may represent postischemic hyperemia, but are probably more frequently secondary to arousal caused by pain. Thus, during the headache phase rCBF may be subnormal, normal or high. These findings do not...

  18. Cerebral abscess in children

    International Nuclear Information System (INIS)

    A cerebral abscess (CA) is a focal, infectious process only or multiple, located in the cerebral parenchyma that produces tisular lysis and it behaves like a lesion of space occupative, being a suppurative illness, who origin is a distant infection, or for continuity that studies initially as an area of focal cerebritis and it is developed to a collection surrounded purulent. At the moment they are perfecting technical and protocols diagnoses and therapeutic and measures for allow to control the natural history of the illness, making from the confrontation to this pathology a necessarily interdisciplinary complicated art, stiller in the infantile population, due to their difficulty in the diagnosis and the relevance of the same one. The paper includes epidemiology, etiology, risk factors, localization, pathology, clinic, diagnoses, treatment and diagnostic images

  19. In vitro validation of endovascular Doppler-derived flow rates in models of the cerebral circulation.

    Science.gov (United States)

    McGah, P M; Nerva, J D; Morton, R P; Barbour, M C; Levitt, M R; Mourad, P D; Kim, L J; Aliseda, A

    2015-11-01

    This study presents validation of endovascular Doppler velocimetry-based volumetric flow rate measurements conducted in a pulsatile flow loop simulating conditions in both the internal carotid and basilar artery. In vitro models of cerebral vessels, each containing an aneurysm, were fabricated from patient anatomies extracted from 3D rotational angiography. Flow velocity measurements were collected with three different experimental techniques: an endovascular Doppler wire, Particle Image Velocimetry, and a time-resolved ultrasonic flow meter. Womersley's theory of pulsatile flow in a cylindrical vessel was used to compute time-resolved volumetric flow rates from the endovascular Doppler velocity. The volumetric flow rates computed from the Doppler measurements were compared to those from the Particle Image Velocimetry profile measurements, and the direct measurements from the ultrasonic flow meter. The study establishes confidence intervals for any systematic or random errors associated with the wire-derived flow rates as benchmarked to the other two modalities. There is an approximately 10% random error in the Doppler-derived peak and time-averaged flow rates. There is a measurable uniform bias, about 15% too low, in the time-averaged Doppler-derived flow rates. There is also a small proportional bias in the peak systolic Doppler-derived flow rates. Potential sources of error are also discussed. PMID:26450643

  20. Cerebral fat embolism

    International Nuclear Information System (INIS)

    A case of cerebral fat embolism is reported. A 18-year-old patient with multiple bone fractures was in semiconma immediately after an injury. Brain CT showed no brain swelling or intracranial hematoma. Hypoxemia and alcoholemia were noted on admission, which returned to normal without improvement of consciousness level. In addition, respiratory symptoms with positive radiographic changes, tachycardia, pyrexia, sudden drop in hemoglobin level, and sudden thrombocytopenia developed. These symptoms were compatible with Gurd's criteria of systemic fat embolism. Eight days after injury, multiple low density areas appeared on CT and disappeared within the subsequent two weeks, and subdural effusion with cerebral atrophy developed. These CT findings were not considered due to cerebral trauma. Diagnosis of cerebral fat embolism was made. The subdural effusion was drained. Neurologic and pulmonary recoveries took place slowly and one month following the injury the patient became alert and exhibited fully coordinated limb movement. The CT scans of the present case well corresponded with hitherto reported pathological findings. Petechiae in the white matter must have developed on the day of injury, which could not be detected by CT examination. It is suggested that some petechial regions fused to purpuras and then gradually resolved when they were detected as multiple low density areas on CT. CT in the purpuras phase would have shown these lesions as high density areas. These lesions must have healed with formation of tiny scars and blood pigment which were demonstrated as the disappearance of multiple low density areas by CT examination. Cerebral atrophy and subsequent subdural effusion developed as a result of demyelination. The patient took the typical clinical course of cerebral fat embolism and serial CT scans served for its assessment. (author)

  1. Cerebral palsy and congenital malformations

    DEFF Research Database (Denmark)

    Garne, Ester; Dolk, Helen; Krägeloh-Mann, Inge;

    2007-01-01

    were reported to have a congenital malformation. The majority (8.6% of all children) were diagnosed with a cerebral malformation. The most frequent types of cerebral malformations were microcephaly and hydrocephaly. Non-cerebral malformations were present in 97 CP children and in further 14 CP children...

  2. Stellarator helical vacuum vessel

    International Nuclear Information System (INIS)

    A design study of a stainless steel, heavy wall, helically shaped vacuum torus has been made for use in a proposed Stellarator configuration. The study concerns itself with the shape of the vacuum vessel and the division of the vessel into components that can be machined and welded together into a helical configuration. A complication in the design requires that a circular magnet coil be located at the minor toroidal axis and that this coil be embedded within the periphery of the vacuum vessel. The vacuum vessel has a minor toroidal axis diameter of 4 meters, a 68.6-cm shell diameter, and a 1.9-cm wall thickness. It twists about the minor toroidal axis twice in 3600C. (An n value of 2). It is proposed that the unit be made of cylindrical segments with the ends of the cylinders cut at appropriate lengths and angles to form the helix. A mathematical derivation of the dimensions necessary to produce the required shapes of the segments has been made. Also, drawings of the vacuum vessel components have been produced on LANL's CTR CAD/CAM system. The procedure developed can be used for any value of n as dictated by physics requirements

  3. Reactor vessel annealing system

    Science.gov (United States)

    Miller, Phillip E.; Katz, Leonoard R.; Nath, Raymond J.; Blaushild, Ronald M.; Tatch, Michael D.; Kordalski, Frank J.; Wykstra, Donald T.; Kavalkovich, William M.

    1991-01-01

    A system for annealing a vessel (14) in situ by heating the vessel (14) to a defined temperature, composed of: an electrically operated heater assembly (10) insertable into the vessel (14) for heating the vessel (14) to the defined temperature; temperature monitoring components positioned relative to the heater assembly (10) for monitoring the temperature of the vessel (14); a controllable electric power supply unit (32-60) for supplying electric power required by the heater assembly (10); a control unit (80-86) for controlling the power supplied by the power supply unit (32-60); a first vehicle (2) containing the power supply unit (32-60); a second vehicle (4) containing the control unit (80-86); power conductors (18,22) connectable between the power supply unit (32-60) and the heater unit (10) for delivering the power supplied by the power supply unit (32-60) to the heater assembly (10); signal conductors (20,24) connectable between the temperature monitoring components and the control unit (80-86) for delivering temperature indicating signals from the temperature monitoring components to the control unit (80-86); and control conductors (8) connectable between the control unit (80-86) and the power supply unit (32-60) for delivering to the power supply unit (32-60) control signals for controlling the level of power supplied by the power supply unit (32-60) to the heater assembly (10).

  4. Acrylic vessel cleaning tests

    International Nuclear Information System (INIS)

    The acrylic vessel as constructed is dirty. The dirt includes blue tape, Al tape, grease pencil, gemak, the glue or residue form these tapes, finger prints and dust of an unknown composition but probably mostly acrylic dust. This dirt has to be removed and once removed, the vessel has to be kept clean or at least to be easily cleanable at some future stage when access becomes much more difficult. The authors report on the results of a series of tests designed: (a) to prepare typical dirty samples of acrylic; (b) to remove dirt stuck to the acrylic surface; and (c) to measure the optical quality and Th concentration after cleaning. Specifications of the vessel call for very low levels of Th which could come from tape residues, the grease pencil, or other sources of dirt. This report does not address the concerns of how to keep the vessel clean after an initial cleaning and during the removal of the scaffolding. Alconox is recommended as the cleaner of choice. This acrylic vessel will be used in the Sudbury Neutrino Observatory

  5. Middle cerebral artery blood velocity and cerebral blood flow and O2 uptake during dynamic exercise

    DEFF Research Database (Denmark)

    Madsen, P L; Sperling, B K; Warming, T; Schmidt, J F; Secher, N H; Wildschiødtz, Gordon; Holm, S; Lassen, N A

    1993-01-01

    Results obtained by the 133Xe clearance method with external detectors and by transcranial Doppler sonography (TCD) suggest that dynamic exercise causes an increase of global average cerebral blood flow (CBF). These data are contradicted by earlier data obtained during less-well-defined conditions....... To investigate this controversy, we applied the Kety-Schmidt technique to measure the global average levels of CBF and cerebral metabolic rate of oxygen (CMRO2) during rest and dynamic exercise. Simultaneously with the determination of CBF and CMRO2, we used TCD to determine mean maximal flow...... velocity in the middle cerebral artery (MCA Vmean). For values of CBF and MCA Vmean a correction for an observed small drop in arterial PCO2 was carried out. Baseline values for global CBF and CMRO2 were 50.7 and 3.63 ml.100 g-1.min-1, respectively. The same values were found during dynamic exercise...

  6. Endovascular rescue from arterial rupture and thrombosis during middle cerebral artery stenting

    International Nuclear Information System (INIS)

    Intravascular stents are being used with increasing frequency in interventional neuroradiology. Iatrogenic arterial rupture is an uncommon but serious complication. We present a case of arterial rupture and subarachnoid haemorrhage during middle cerebral artery stenting, treated by emergency additional, overlapping stenting and balloon tamponade of the dissected vessel. Thrombotic occlusion of the artery was managed by intra-arterial abciximab. Normal vessel patency was re-established within 20 min and the patient recovered with no neurological deficit. (orig.)

  7. Fetal cerebral-umbilical Doppler ratio in prediction of fetal distress in patients with preeclampsia

    OpenAIRE

    Jurišić Aleksandar; Jurišić Žaklina; Pažin Vladimir; Vasiljević Mladenko; Janković-Ražnatović Svetlana; Dragojević-Dikić Svetlana

    2010-01-01

    Bacground/Aim. The use of color Doppler ultrasonography provides noninvasive observation, confirmation and quantification of pathophysiological processes in fetoplacental circulation in pregnant patients. By blood vessel mapping and the obtained waves spectral analysis it is possible to evaluate vascular resistency of the fetus blood vessels. The aim of the study was to evaluate cerebral-umbilical pulsatility index ratio in fetal circulation in prediction of fetal distress in patients with pr...

  8. Functional photoacoustic tomography for non-invasive imaging of cerebral blood oxygenation and blood volume in rat brain in vivo

    Science.gov (United States)

    Wang, Xueding; Xie, Xueyi; Ku, Geng; Stoica, George; Wang, Lihong V.

    2005-04-01

    Based on the multi-wavelength laser-based photoacoustic tomography, non-invasive in vivo imaging of functional parameters, including the hemoglobin oxygen saturation and the total concentration of hemoglobin, in small-animal brains was realized. The high sensitivity of this technique is based on the spectroscopic differences between oxy- and deoxy-hemoglobin while its spatial resolution is bandwidth-limited by the photoacoustic signals rather than by the optical diffusion as in optical imaging. The point-by-point distributions of blood oxygenation and blood volume in the cerebral cortical venous vessels, altered by systemic physiological modulations including hyperoxia, normoxia and hypoxia, were visualized successfully through the intact skin and skull. This technique, with its prominent intrinsic advantages, can potentially accelerate the progress in neuroscience and provide important new insights into cerebrovascular physiology and brain function that are of great significance to the neuroscience community.

  9. Study of cerebral blood flow in patients with cerebral infarction by 133Xe inhalation method

    International Nuclear Information System (INIS)

    Cerebral blood flow in both hemispheres was studied by the Xe-133 inhalation method in 49 patients with cerebral infarction in the unilateral hemisphere. They were classified into three groups by computed tomographic findings as follows: relatively large low density lesion including the cerebral cortex and subcortex (group I), relatively large low density lesion including the subcortical white matter and basal ganglia (group II), and small low density lesion including the subcortical white matter (group III). Mean cerebral blood flow (mCBF) in the affected hemisphere was markedly low in group I, moderately low in group II, and slightly low in group III. Several cases in groups I and II revealed remarkable changes of mCBF within one month after the onset. The mCBF in both hemispheres was lower in group I than in groups II and III within one week after the onset. Seven to 12 weeks later, mCBF was lower in the affected hemisphere than in the unaffected one in groups I and II: This was lower when compared with that in group III. There was almost no difference in mCBF between the affected and unaffected hemispheres in group III. Sequential changes of mCBF in both hemispheres were divided into 7 types in reevaluable 27 patients. Sequential changes of mCBF in both hemispheres of the patients with cerebral infarction were considered to be caused mainly by recanalization and hemorrhagic infarction. (J.P.N.)

  10. Malignant cerebral swelling following cranioplasty.

    Science.gov (United States)

    Honeybul, S; Damodaran, O; Lind, C R P; Lee, G

    2016-07-01

    Over the past few years there have been a number of case reports and small cohort studies that have described so called "malignant" cerebral swelling following an uneventful cranioplasty procedure. The pathophysiology remains to be established however it has been suggested that it may be related to a combination of failure of autoregulation and the use of closed vacuum suction drainage. The current study presents three further patients who had had a decompressive hemicraniectomy for ischaemic stroke. If decompressive craniectomy is utilised in the management of neurological emergencies, close attention and wider reporting of this type of complication is required not only to focus attention on possible management strategies, but also to determine which patients are at most risk of this devastating complication. PMID:27189792

  11. Cerebral atrophic and degenerative changes following various cerebral diseases, (1)

    International Nuclear Information System (INIS)

    Patients having cerebral atrophic and degenerative changes following hypoglycemia, cerebral contusion, or cerebral hypoxia including cerebrovascular disorders were reported. Description was made as to cerebral changes visualized on CT images and clinical courses of a patient who revived 10 minutes after heart stoppage during neurosurgery, a newborn with asphyxia, a patient with hypoglycemia, a patient who suffered from asphyxia by an accident 10 years before, a patient with carbon monoxide poisoning at an acute stage, a patient who had carbon monoxide poisoning 10 years before, a patient with diffuse cerebral ischemic changes, a patient with cerebral edema around metastatic tumor, a patient with respiration brain, a patient with neurological sequelae after cerebral contusion, a patient who had an operation to excise right parietal lobe artery malformation, and a patient who was shooted by a machine gun and had a lead in the brain for 34 years. (Tsunoda, M.)

  12. Low-frequency oscillations and vasoreactivity of cortical vessels in obstructive sleep apnea during wakefulness

    DEFF Research Database (Denmark)

    Schytz, Henrik Winther; Jensen, Benedicte Ersted; Jennum, Poul;

    2013-01-01

    Effective nasal continuous positive airway pressure (CPAP) therapy reduces the cardiovascular outcomes associated with obstructive sleep apnea (OSA), but the mechanism behind this effect is unclear. We investigated if OSA patients during wakefulness showed signs of increased sympathetic activity...... and decreased vasoreactivity in cerebral cortical vessels as measured with near-infrared spectroscopy (NIRS), and if this may be reversed by CPAP treatment....

  13. Reactor pressure vessel materials

    International Nuclear Information System (INIS)

    As a result of the popularity of the Agencies report 'Neutron Irradiation Embrittlement of Reactor Pressure Vessel Steels' of 1975, it was decided that another report on this broad subject would be of use. In this report, background and contemporary views on specially identified areas of the subject are considered as self-contained chapters, written by experts. Chapter 3 offers a detailed treatment of the selection criteria and properties of reactor pressure vessel materials. The main attention is directed towards steel and ingot making and the subsequent material processing

  14. Effect of glycerol on cerebral blood flow in the cases of cerebral infarction in the chronic phase

    International Nuclear Information System (INIS)

    This report concerns the evaluation of the effects of glycerol for the treatment of cerebral infarction in the chronic phase. For this purpose, cerebral blood flow (CBF) was determined after glycerol loading in 19 patients, including 24 affected hemispheres. The mean global increase in CBF after glycerol infusion was 11.1%. The cases were classified into two groups: main trunk disease (Group A; occlusion or stenosis), and non-main trunk disease (Group B). Group A had a 6.4% decrease in CBF in the affected hemisphere and a 6.5% increase in the contralateral hemisphere. By contrast, the CBF of Group B increased by 20.2% and 14.8% in the affected and contralateral hemisphere, respectively. In the cases of cerebral infarction associated with main trunk disease, the functional reserve capacity of cerebral vessels may decrease significantly. Moreover, the steal phenomenon of CBF may occur in these cases after glycerol loading. Hence, glycerol infusion for the treatment of cerebral infarction in the chronic phase should be used with care, preferably after CBF measurements. (author)

  15. An intelligent three dimensional reconstruction system for cerebral arteries from biplane cineangiograms

    International Nuclear Information System (INIS)

    In this study, an intelligent system is developed for the three dimensional reconstruction of cerebral arteries from biplane cineangiograms. The system is composed of two blocks, i.e., an inferencing-control-block and a processing-block. The inferencing-control block controls the flow of the image-processing by inferencing with the knowledge stored in the block and is a production system based on 'IF, THEN' rule. The processing-block is a collection of image processing procedures activated by a call from the inferencing-control-block. On the other hand, the flow of the image-processing is outlined as follows: After the extraction of vessel center lines from the angiograms, the blood flow directions and connectivity states of vessels are determined and the vessel graph is translated to a vessel connectivity tree. Then, by utilizing the knowledge about anatomic structure of cerebral arteries and characteristics of angiograms, important arteries are distinguished and vessel groups classified. Finally, by using a shape-oriented matching method, the vessels on the two projected planes are matched and the three dimensional structure of vessels constructed. An example is presented to demonstrate the effectiveness of the use of the knowledge which enables the system to improve the efficiency and precision of the processing, such as vessel analysis and matching. (author)

  16. Trigeminal origin or B-preprotachykinin products in feline pial blood vessels

    International Nuclear Information System (INIS)

    A specific and sensitive radioimmunoassay measured the presence of immunoreactive neurokinin A within feline and human pial arteries. Immunoreactivity exhibited a retention time identical to that of synthetic peptide when acid extracts from feline and human blood vessels were subjected to reverse-phase high-performance liquid chromatography. As shown previously for substance P, levels of immunoreactive neurokinin A decreased significantly in the vessels from the ipsilateral rostral circle of Willis l9-24 days following unilateral trigeminal ganglionectomy. Hence, trigeminal projections to cerebral blood vessels contain both products of B-preprotachykinin mRNA. (author)

  17. Evaluation of measurement parameters in clinical cerebral MR angiography

    International Nuclear Information System (INIS)

    A three-dimensional MR angiography technique was developed in patients and volunteers that can produce clinically useful studies of the cerebral vasculature with multiple views possible from a single data set acquisition. A low-flip angle, three-dimensional fast imaging with steady precessing sequence was found to provide the optimal vessel/soft-tissue contrast related to the tissues' relaxation parameters and inflow. The inflowing unsaturated spins and vessel orientation made an axial acquisition most effective. The flow-related phase dispersion could be largelly corrected with the appropriate orientation, strength, order, and combination of refocusing gradients with the shortest possible echo times. Reduced voxel size also affected the phase dispersion due to motion and field inhomogeneities. Postprocessing yielded projection images of vessels throughout the three-dimensional volume

  18. Sodium recovery vessel

    International Nuclear Information System (INIS)

    Purpose: To enable to efficiently separate and recover sodium or reaction product in the secondly coolant circuit of FBR type nuclear power plant. Constitution: an upper element is disposed above a cyclone in a sodium recovery vessel, to which a gas formed by sodium-water reaction is caused to flow. Sodium and gases formed by sodium-water reaction introduced from a gas inlet of pressure open system pipeways descend downwardly as swirling stream in a cylindrical vessel within the circumferential flow channel along the outer wall of the shround surrounding the cyclone and the inner wall of the cylindrical vessel. In this case, liquid sodium is separated from the gas, falls to the bottom of the cylindrical vessel as an accumulated liquid. The gas stream passes between each of the elements in the upper element to enable separation of sodium or reaction product, as well as separated sodium and reaction product are urged to the outer circumferential side since all of the upper element and the buffer plate are arranged with their outer circumferential being lowered. (Horiuchi, T.)

  19. Pressure vessel control

    International Nuclear Information System (INIS)

    The in-service inspection machine (MIS) is robot machine which aim is to inspect, under water, the PWR type vessels (with high radiation level): inspection of the welded joints, of the coatings, detection of the defects situated under the coating, etc... This type of machine utilizes several non destructive testing technologies: ultrasonics with focused transducers, gammagraphy, television, and eddy currents

  20. The Association of Type 2 Diabetes Mellitus with Cerebral Gray Matter Volume Is Independent of Retinal Vascular Architecture and Retinopathy

    Directory of Open Access Journals (Sweden)

    C. Moran

    2016-01-01

    Full Text Available It is uncertain whether small vessel disease underlies the relationship between Type 2 Diabetes Mellitus (T2DM and brain atrophy. We aimed to study whether retinal vascular architecture, as a proxy for cerebral small vessel disease, may modify or mediate the associations of T2DM with brain volumes. In this cross-sectional study using Magnetic Resonance Imaging (MRI scans and retinal photographs in 451 people with and without T2DM, we measured brain volumes, geometric measures of retinal vascular architecture, clinical retinopathy, and MRI cerebrovascular lesions. There were 270 people with (mean age 67.3 years and 181 without T2DM (mean age 72.9 years. T2DM was associated with lower gray matter volume (p=0.008. T2DM was associated with greater arteriolar diameter (p=0.03 and optimality ratio (p=0.04, but these associations were attenuated by adjustments for age and sex. Only optimality ratio was associated with lower gray matter volume (p=0.03. The inclusion of retinal measures in regression models did not attenuate the association of T2DM with gray matter volume. The association of T2DM with lower gray matter volume was independent of retinal vascular architecture and clinical retinopathy. Retinal vascular measures or retinopathy may not be sufficiently sensitive to confirm a microvascular basis for T2DM-related brain atrophy.

  1. Sustainable Oceanographic Vessels - Setting an Example

    Science.gov (United States)

    van Leer, J. C.

    2009-12-01

    In response to climate change, global warming and post “peak oil” fuel scarcity, the oceanographic community should consider reducing its carbon foot print. Why should scientists operate inefficient vessels while lecturing the general public on the need to reduce CO2 emissions? We have already seen curtailment of ship schedules and ship lay-ups, due in part to rising fuel costs, following $140/barrel crude oil. When the global recession ends, upward pressure on oil prices will again commence. Who can forecast how high fuel prices may ultimately rise during the typical 25-30 year lifetime of a research vessel? Are we to curtail future work at sea when oceanic climate research is becoming ever more important? A catamaran research vessel has been designed which can be electrically propelled from by a combination of high efficiency generators, photovoltaic panels and/or sails. Sail produced power is transformed with propellers and motor/generators into electric power which is stored in battery banks. This vessel could operate as the first true hybrid oceanographic research vessel. It could even continue operations without fuel in cases of a severe fuel shortage or fueling denial. Since the power produced by any water turbine increases with the cube of the velocity flowing over its propeller, the low fluid friction and high stability of a catamaran, with reasonably slender hulls, provide an important boost to efficient hybrid operation. The author has chartered a 42’ hybrid catamaran sailboat and found it efficient and extremely easy to operate and control. A 79’ motor sailing catamaran research vessel by Lock Crowther Designs will be presented as one example of a sustainable research vessel with excellent speed and sea-keeping. A center well makes operation as a small drilling/coring ship for coastal climate investigation possible. The center well also supports a host of remote sensing and robotic gear handling capabilities.

  2. Doppler sonography of extracranial and intracranial vessels in patients with thrombotic stroke

    Directory of Open Access Journals (Sweden)

    Farhad Iranmanesh

    2006-12-01

    Full Text Available INTRODUCTION: The results of intracranial and extracranial vessel color Doppler sonography, which is now an inseparable part of patient evaluation, vary in different studies. The objective of this study was to evaluate the pattern of vascular involvement in thrombotic stroke and its relationship with risk factors of stroke. METHODS: One-hundred patients (45 males and 55 females with thrombotic stroke underwent transcranial sonography and color Doppler sonography of extracranial vessels. The pattern of vascular involvement was analyzed. The risk factors of stroke were also evaluated. RESULTS: Forty-seven percent of the studied individuals had some variations in their color Doppler sonography of extracranial vessels, 27% had changes in the intracranial vessels and 26% showed changes in both. The most frequently involved vessels among the intracranial and extracranial vessels were the middle cerebral artery and the internal carotid artery, respectively. The pattern of vascular involvement was unrelated to hypertension, cigarette smoking, diabetes mellitus, dyslipidemia or history of ischemic heart disease. Extracranial involvement in patients with positive history of MI was more prevalent than in those without such history. CONCLUSIONS: Extracranial vessel involvement in thrombotic stroke was found to be more prevalent than intracranial vessel involvement in the city of Rafsanjan; however, intracranial vessel involvement was more prevalent than in western countries. KEY WORDS: Thrombotic stroke, color Doppler sonography, intracranial vessels, extracranial, cerebrovascular risk factors

  3. Parálisis cerebral Cerebral palsy

    OpenAIRE

    Jorge Malagon Valdez

    2007-01-01

    El término parálisis cerebral (PC) engloba a un gran número de síndromes neurológicos clínicos, de etiología diversa. Estos síndromes se caracterizan por tener una sintomatología común: los trastornos motores. Algunos autores prefieren manejar términos como "encefalopatía fija", "encefalopatías no evolutivas". Se mencionan la utilidad de programas de intervención temprana y métodos especiales de rehabilitación, así como el manejo de las deficiencias asociadas como la epilepsia, deficiencia me...

  4. Parálisis cerebral Cerebral palsy

    Directory of Open Access Journals (Sweden)

    Jorge Malagon Valdez

    2007-01-01

    Full Text Available El término parálisis cerebral (PC engloba a un gran número de síndromes neurológicos clínicos, de etiología diversa. Estos síndromes se caracterizan por tener una sintomatología común: los trastornos motores. Algunos autores prefieren manejar términos como "encefalopatía fija", "encefalopatías no evolutivas". Se mencionan la utilidad de programas de intervención temprana y métodos especiales de rehabilitación, así como el manejo de las deficiencias asociadas como la epilepsia, deficiencia mental, trastornos del lenguaje, audición, visión, déficit de la atención que mejoran el pronóstico de manera significativa. El pronóstico también depende de la gravedad del padecimiento y de las manifestaciones asociadas.The term cerebral palsy (CP, is used for a great number of clinical neurological syndromes. The syndromes are characterized by having a common cause, motor defects. It is important, because they can cause a brain damage by presenting motor defects and some associated deficiencies, such as mental deficiency, epilepsy, language and visual defects and pseudobulbar paralysis, with the nonevolving fact. Some authors prefer using terms such as "non-evolving encephalopathies". In the treatment the utility of prevention programs of early stimulation and special rehabilitation methods, and treatment of associated deficiencies such as epilepsy, mental deficiency, language, audition and visual problems, and the attention deficit improve the prognosis in an important way. The prognosis depends on the severity of the disease and the associated manifestations.

  5. 微小血管端端连续吻合与间断吻合的比较研究%Comparison of continuous and interrupted suture technique in end - to - end anastomosis of small sized vessels

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    目的 评价直径为0.7 ~ 2 mm的血管用连续端端吻合法的价值。方法 对45只成年兔及30只成年鼠,随机分成外径为0.8 mm(,下同)、1.5 mm、1.9 mm的动脉组和外径为2.1 mm、1.1 mm的静脉组,共5组。每组动物一侧用端端连续吻合,另一侧用间断吻合。术后1、2、4周,各组选5只实验动物,行勒血试验、血管造影和组织学检查。结果 与血管间断吻合相比,血管连续吻合的时间能降低47 % ~ 22 %( P 0.05)。结论 与间断吻合技术相比,连续端端吻合外径为0.7 mm ~ 2.2 mm的血管,能明显节省吻合时间。%Objective To evaluate the merits of the continuous suture technique (CST)in end - to - end anastomosis of vessels with external diameter (ED) less than 2.0 mm. Methods A total of 45 adult rabbits and 30 adult rats were used. The experiment was composed of five groups (n=15 for each),group Ⅰ: rabbit carotid artery (1.8~2.0 mm ED), group Ⅱ: rabbit femoral artery (1.4~1.6 mm ED), group Ⅲ: rat femoral artery (0.7~0.9 mm ED), group Ⅳ: rabbit femoral vein (2.0~2.2 mm ED), and group Ⅴ: rat femoral vein (1.0~1.2 mm ED). In each animal, one side of the vessel was repaired using the CST, and the contralateral vessel with the interrupted suture technique (IST), Milk test, angiography and histological study of the anastomosed vessels were carried out to 5 animals from each group at 1, 2, and 4 weeks postoperatively. Results There was no significant difference in patency rate, thrombus formation, and healing of vascular intima between the two suture techniques in vessels of any size. However, when compared to the IST, the CST could significantly (P<0.01) reduce anastomosis time by 22 % to 47 %.Conclusions The CST is a reliable and time - saving procedure in the end - to - end anastomosis of vessels with external diameter ranging from 0.7 mm to 2.2 mm.

  6. Triptan-induced contractile (5-HT1B receptor) responses in human cerebral and coronary arteries

    DEFF Research Database (Denmark)

    Edvinsson, Lars; Uddman, Erik; Wackenfors, Angelica; Davenport, Anthony; Longmore, Jenny; Malmsjö, Malin

    2005-01-01

    Triptans are agonists at 5-HT1B and 5-HT1D (where 5-HT is 5-hydroxytryptamine; serotonin) receptors and cause vasoconstriction of isolated blood vessels. The aim of the present study was to determine vasoconstrictor potency (EC50) of triptans in human coronary and cerebral arteries and to examine...

  7. Cerebral infarction showed hyperperfusion pattern on radionuclide cerebral angiography

    International Nuclear Information System (INIS)

    Four patients of middle cerebral infarctin showed hyperperfusion on radionuclide cerebral angiography and fan-shape accumulation at the area of middle cerebral artery on early and delayed brain scan. In these patients, bone scanning agents such as sup(99m)Tc-EHDP or sup(99m)Tc-MDP also prominently accumulated at the area of infarction. These findings were observed on the study when it was performed within seventeen days after attack, but reexamination tended to show normal or decreased perfusion on radionuclide cerebral angiography and improve abnormal accumulation on brain scans. The clinical diagnosis of these three patients were cerebral embolism with heart disease, but one patient was internal carotid artery occlusion. The prognosis of all patients were very good. The hyperperfusion on radionuclide cerebral angiography of these patients represents the luxury perfusion in the lesion and these infarction has been called hot stroke by Yarnell et al. (author)

  8. Progressive Deconstruction of a Distal Posterior Cerebral Artery Aneurysm Using Competitive Flow Diversion.

    Science.gov (United States)

    Johnson, Andrew K; Tan, Lee A; Lopes, Demetrius K; Moftakhar, Roham

    2016-03-01

    Progressive deconstruction is an endovascular technique for aneurysm treatment that utilizes flow diverting stents to promote progressive thrombosis by diverting blood flow away from the aneurysm's parent vessel. While the aneurysm thromboses, collateral blood vessels develop over time to avoid infarction that can often accompany acute parent vessel occlusion. We report a 37-year-old woman with a left distal posterior cerebral artery aneurysm that was successfully treated with this strategy. The concept and rationale of progressive deconstruction are discussed in detail. PMID:26958413

  9. Focal ischaemia caused by instability of cerebrovascular tone during attacks of hemiplegic migraine. A regional cerebral blood flow study

    DEFF Research Database (Denmark)

    Friberg, L; Olsen, T S; Roland, P E; Lassen, N A

    cerebral vessels (arterioles) alternating with a normal calibre for these vessels and/or short periods of vasodilatation. It isconsidered to be a primary pathological condition of the vessels. When vasoconstriction was present the blood flow decreased to values consistent with ischaemia, which was probably......During the course of hemiplegic migraine in 3 patients, changes in regional cerebral blood flow (rCBF) were recorded by the intracarotid 133Xe method and a 254 multidetector camera covering one hemisphere. The rCBF measurements were performed in conjunction with cerebral angiography. During...... patients developed transient motor and/or sensory deficits and subsequently severe headache. No signs of arterial occlusion were found. In the over and underperfused regions blood flow fluctuated rapidly because of instability of cerebrovascular tone, defined as transient constriction of the smallest...

  10. Puerto Rico Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Puerto Rico. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  11. American Samoa Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for American Samoa. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  12. Hawaii Abandoned Vessel Inventory, Lanai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Lanai. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  13. Hawaii Abandoned Vessel Inventory, Oahu

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Oahu, Hawaii. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  14. For-Hire Vessel Directory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Directory is maintained as the sample frame for the For-Hire Survey. I contains data on for-hire vessels on the Atlantic and Gulf coasts. Data include...

  15. CNMI Abandoned Vessel Inventory, Rota

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Rota. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  16. Hawaii Abandoned Vessel Inventory, Molokai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Molokai, Hawaii. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of...

  17. CNMI Abandoned Vessel Inventory, Saipan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Saipan. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  18. CNMI Abandoned Vessel Inventory, Tinian

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Tinian. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  19. Hawaii Abandoned Vessel Inventory, Kauai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Kauai. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  20. Hawaii Abandoned Vessel Inventory, Maui

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Maui. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  1. Vessels in Transit - Web Tool

    Data.gov (United States)

    Department of Transportation — A web tool that provides real-time information on vessels transiting the Saint Lawrence Seaway. Visitors may sort by order of turn, vessel name, or last location in...

  2. Altered low frequency oscillations of cortical vessels in patients with cerebrovascular occlusive disease – a NIRS study

    DEFF Research Database (Denmark)

    Phillip, Dorte; Iversen, Helle K; Schytz, Henrik W;

    2013-01-01

    Analysis of cerebral autoregulation by measuring spontaneous oscillations in the low frequency spectrum of cerebral cortical vessels might be a useful tool for assessing risk and investigating different treatment strategies in carotid artery disease and stroke. Near infrared spectroscopy (NIRS) is...... patients with both symptomatic carotid occlusive disease and cerebral hypoperfusion in comparison to healthy controls. Each hemisphere was examined with two NIRS channels using a 3 cm source detector distance. Arterial blood pressure (ABP) was measured via a finger plethysmograph. Using transfer function...

  3. Reactor vessel stud closure system

    International Nuclear Information System (INIS)

    A quick-acting stud tensioner apparatus for enabling the loosening or tightening of a stud nut on a reactor vessel stud. The apparatus is adapted to engage the vessel stud by closing a gripper around an upper end of the vessel stud when the apparatus is seated on the stud. Upon lifting the apparatus, the gripper releases the vessel stud so that the apparatus can be removed

  4. Prestressed cast iron pressure vessels as burst-proof pressure vessels for innovative nuclear applications

    International Nuclear Information System (INIS)

    The amendment to the German Atomic Energy Act from July 28, 1994 requires that events 'whose occurrence is practically excluded by the measures against damages', i.e. events of the category residual risk, must not necessitate far reaching protective measures outside the plant. For a conventional reactor pressure vessel, the residual risk consists in the very small probability of a catastrophic failure (formation of a large fracture opening, bursting of the vessel). With a prestressed cast iron vessel (PCIV), the formation of a large fracture opening or bursting of the vessel, respectively, is impossible due to its design properties. Against this background the possibility of the use of this type of pressure vessel for lightwater reactors has been studied in the frame of a 'Working Group for Innovative Nuclear Technology', founded by different research institutes and industrial companies. Furthermore, it has been studied whether the use of the PCIV support the realization of a corecatcher system. The results are presented in this report. Already many years earlier, Siempelkamp has performed industrial development and Forschungszentrum Juelich related experimental and theoretical safety research for the PCIV as an innovative, bust-proof pressure vessel concept. This development of the PCIV as well as its safety properties are also presented in a conclusive manner. (orig.)

  5. Pressure vessel design manual

    Energy Technology Data Exchange (ETDEWEB)

    Moss, D.R.

    1987-01-01

    The first section of the book covers types of loadings, failures, and stress theories, and how they apply to pressure vessels. The book delineates the procedures for designing typical components as well as those for designing large openings in cylindrical shells, ring girders, davits, platforms, bins and elevated tanks. The techniques for designing conical transitions, cone-cylinder intersections, intermediate heads, flat heads, and spherically dished covers are also described. The book covers the design of vessel supports subject to wind and seismic loads and one section is devoted to the five major ways of analyzing loads on shells and heads. Each procedure is detailed enough to size all welds, bolts, and plate thicknesses and to determine actual stresses.

  6. The mechanism of cerebral aneurysmal formation

    International Nuclear Information System (INIS)

    Cerebral aneurysm is a disease of poor prognosis and MR- and CT-angiographies are used for its diagnosis and in the preventive therapy of its rupture. Here discussed are formation and growth leading to rupture of the lesion for its advanced diagnosis and prevention of rupturing. Beginning from findings in animal experimentation in mice, rats and monkeys, discussed are pathology of the aneurysm, genes related with its formation, molecular biological approaches concerning apoptosis and NF-kB/TNF-α related inflammatory reactions, participation of sex hormone, clinical hemodynamic analyses based on 3D data from CT and MRI findings, and clinical studies. Authors consider that local hemodynamic stress loading is possibly related to cerebral aneurysm formation as it is yielded at the loading part of the vessel in human and in animal models. The aneurysm is possibly a result of remodeling disturbance by the load and subsequent excessive involution of the artery. In the process, probably included are the inflammation, apoptosis, degradation of extracellular matrix and functional impairment of endotherial cells. Future elucidation of molecular mechanisms underlying the aneurismal growth and rupture will bring about the improved treatment to prevent the disease by stabilizing the aneurismal wall. (T.T.)

  7. Bidirectional encroachment of collagen into the tunica media in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy

    OpenAIRE

    Dong, Hairong; BLAIVAS, MILA; Michael M Wang

    2012-01-01

    Arteries in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are susceptible to smooth muscle loss and fibrosis, but the molecular components underlying these dramatic vascular changes are not well characterized. The purpose of this study was to investigate the distribution of collagen isoforms in the cerebral vessels of North American CADASIL patients with classical NOTCH3 mutations. Expression of type I-VI collagen in brains obtained at au...

  8. Phenylpropanolamine and cerebral hemorrhage

    International Nuclear Information System (INIS)

    Computerized tomography, carotid angiograms, and arteriography were used to diagnose several cases of cerebral hemorrhage following the use of phenylpropanolamine. The angiographic picture in one of the three cases was similar to that previously described in association with amphetamine abuse and pseudoephedrine overdose, both substances being chemically and pharmacologically similar to phenylpropanolamine. The study suggests that the arterial change responsible for symptoms may be due to spasm rather than arteriopathy. 14 references, 5 figures

  9. Nanomedicine in cerebral palsy

    OpenAIRE

    Balakrishnan B; Nance E; Johnston MV; Kannan R; Kannan S

    2013-01-01

    Bindu Balakrishnan,1 Elizabeth Nance,1 Michael V Johnston,2 Rangaramanujam Kannan,3 Sujatha Kannan1 1Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University; Baltimore, MD, USA; 2Department of Neurology and Pediatrics, Kennedy Krieger Institute, Baltimore, MD, USA; 3Department of Ophthalmology, Center for Nanomedicine, Johns Hopkins University, Baltimore, MD, USA Abstract: Cerebral palsy is a chronic childhood disorder that can have diverse etiologies. Injury to the...

  10. Cerebral palsy and aging

    OpenAIRE

    Haak, Peterson; Lenski, Madeleine; HIDECKER, MARY JO COOLEY; Li, Min; Paneth, Nigel

    2009-01-01

    Cerebral palsy (CP), the most common major disabling motor disorder of childhood, is frequently thought of as a condition that affects only children. Deaths in children with CP, never common, have in recent years become very rare, unless the child is very severely and multiply disabled. Thus, virtually all children assigned the diagnosis of CP will survive into adulthood. Attention to the adult with CP has been sparse, and the evolution of the motor disorder as the individual moves through ad...

  11. Osteopenia in cerebral palsy.

    OpenAIRE

    Shaw, N J; White, C. P.; Fraser, W. D.; ROSENBLOOM, L.

    1994-01-01

    The bone mineral density of the lumbar spine was assessed in nine non-ambulant children with cerebral palsy combined with measurements of serum 25-hydroxyvitamin D, parathyroid hormone, and urinary calcium excretion. Three children with recurrent fractures received treatment with bisphosphonates for periods ranging from 12-18 months. All the children demonstrated a severe reduction in bone mineral density even when allowance was made for their body weight. There were no consistent abnormaliti...

  12. Radiopharmaceuticals for cerebral studies

    International Nuclear Information System (INIS)

    For obtain good brain scintillation images in nuclear medicine must be used several radiopharmaceuticals. Cerebral studies give a tumors visual image as well as brain anomalities detection and are helpful in the diagnostic diseases . Are described in this work: a cerebrum radiopharmaceuticals classification,labelled compounds proceeding and Tc 99m good properties in for your fast caption, post administration and blood purification for renal way

  13. Plasticidad cerebral y lenguaje

    OpenAIRE

    Moreno-Torres Sánchez, Ignacio; Berthier Torres, Marcelo Luís

    2012-01-01

    Hace pocos años se daba por sentado que la recuperación del lenguaje tras una lesión cerebral era imposible, al igual que adquirir la lengua materna más allá de los tres primeros años de vida. Sin embargo, las últimas indagaciones muestran que nuestra capacidad de aprender es mucho mayor.

  14. Dysphagia in cerebral palsy

    OpenAIRE

    Salghetti, Annamaria; Martinuzzi, Andrea

    2013-01-01

    Abstract. Feeding problemsare often present in children with neuromotor impairment: dysphagia is usuallyseen in the most severe form of cerebral palsy and it’s defined as thedifficulty with any of the four phases of swallowing. Clinical consequences aremalnutrition and recurrent chest infections that reduce expected duration andquality of life. In order to prevent these consequences it’s important todetect with clinical and instrumental examinations dysphagia symptoms and totreat them. Clinic...

  15. Radioactive material storage vessel

    International Nuclear Information System (INIS)

    In a radioactive material storage vessel having a single sealing boundary in the cylindrical portion and a double sealing boundary in the lid portion, and the outer circumference of the vessel being cooled by air, in which difference is made between the pressure in a radioactive material storage chamber and the pressure in an intermediate chamber present between a primary sealing lid and a secondary sealing lid. A valve is disposed to the primary sealing lid, which breaks the sealing between the radioactive material containing chamber and the intermediate chamber when the difference between the pressure of the containing chamber and that of the intermediate chamber is reduced to lower than a predetermined value, and a sensor for detecting pressure change in the intermediate chamber is disposed to the secondary sealing lid. In addition, a shrinkable member having at least a predetermined length and an extensible length is disposed to the primary sealing lid, and a displacement sensor capable of detecting the change of the length of the shrinkable member is disposed to the secondary sealing lid. Then, when the sealing boundary at the cylinder portion of the radioactive material containing chamber should be broken in the radioactive material storage vessel, it can be detected. (N.H.)

  16. Perfusion MRI in cerebral infarction

    International Nuclear Information System (INIS)

    Purpose: To investigate the hemodynamic changes in patients with acute cerebral stroke by perfusion MRI. Materials and methods: In 12 patients with acute stroke in the territory of the middle cerebral artery, perfusion MRI was performed. Peak time, mean transit time, regional cerebral blood volume and regional cerebral blood flow were calculated in the infarction, the peri-infarction area and the contralateral hemisphere. Results: In the infarction the mean blood flow was 29 ml/100 g/min, compared to about 40 ml/100 g/min in the peri-infarction area and the contralateral hemisphere. In two patients increased cortical blood flow was found in the infarction due to luxury perfusion. The cerebral blood volume was reduced in the infarction, but significantly increased, to 7.3 ml/100 g, in the peri-infarction tissue. Conclusion: Perfusion MRI allows one to differentiate various patterns of perfusion disorders in patients with acute cerebral stroke. (orig./AJ)

  17. Hyperventilation, cerebral perfusion, and syncope

    DEFF Research Database (Denmark)

    Immink, R V; Pott, F C; Secher, N H;

    2014-01-01

    dioxide (PaCO2) and oxygen (PaO2) partial pressures so that hypercapnia/hypoxia increases and hypocapnia/hyperoxia reduces global cerebral blood flow. Cerebral hypoperfusion and TLOC have been associated with hypocapnia related to HV. Notwithstanding pronounced cerebrovascular effects of PaCO2 the......This review summarizes evidence in humans for an association between hyperventilation (HV)-induced hypocapnia and a reduction in cerebral perfusion leading to syncope defined as transient loss of consciousness (TLOC). The cerebral vasculature is sensitive to changes in both the arterial carbon...... contribution of a low PaCO2 to the early postural reduction in middle cerebral artery blood velocity is transient. HV together with postural stress does not reduce cerebral perfusion to such an extent that TLOC develops. However when HV is combined with cardiovascular stressors like cold immersion or reduced...

  18. [Insomnia and cerebral hypoperfusion].

    Science.gov (United States)

    Káposzta, Zoltán; Rácz, Klára

    2007-11-18

    Insomnia is defined as difficulty with the initiation, maintenance, duration, or quality of sleep that results in the impairment of daytime functioning, despite adequate opportunity and circumstances for sleep. In most countries approximately every third inhabitant has insomnia. Insomnia can be classified as primary and secondary. The pathogenesis of primary insomnia is unknown, but available evidence suggests a state of hyperarousal. Insomnia secondary to other causes is more common than primary insomnia. Cerebral hypoperfusion can be the cause of insomnia in some cases. In such patients the cerebral blood flow should be improved using parenteral vascular therapy. If insomnia persists despite treatment, then therapy for primary insomnia should be instituted using benzodiazepine-receptor agonists such as Zolpidem, Zopiclone, or Zaleplon. In those cases Midazolam cannot be used for the treatment of insomnia due to its marked negative effect on cerebral blood flow. In Hungary there is a need to organize multidisciplinary Insomnia Clinics because insomnia is more than a disease, it is a public health problem in this century. PMID:17988972

  19. Cerebral oxygenation and hyperthermia

    Directory of Open Access Journals (Sweden)

    AnthonyRichardBain

    2014-03-01

    Full Text Available Hyperthermia is associated with marked reductions in cerebral blood flow (CBF. Increased distribution of cardiac output to the periphery, increases in alveolar ventilation and resultant hypocapnia each contribute to the fall in CBF during passive hyperthermia; however, their relative contribution remains a point of contention, and probably depends on the experimental condition (e.g. posture and degree of hyperthermia. The hyperthermia-induced hyperventilatory response reduces arterial CO2 pressure (PaCO2 causing cerebral vasoconstriction and subsequent reductions in flow. During supine passive hyperthermia, the majority of recent data indicate that reductions in PaCO2 may be the primary, if not sole, culprit for reduced CBF. On the other hand, during more dynamic conditions (e.g. hemorrhage or orthostatic challenges, an inability to appropriately decrease peripheral vascular conductance presents a condition whereby adequate cerebral perfusion pressure may be compromised secondary to reductions in systemic blood pressure. Although studies have reported maintenance of pre-frontal cortex oxygenation (assessed by near-infrared spectroscopy during exercise and severe heat stress, the influence of cutaneous blood flow is known to contaminate this measure. This review discusses the governing mechanisms associated with changes in CBF and oxygenation during moderate to severe (i.e. 1.0°C to 2.0°C increase in body core temperature levels of hyperthermia. Future research directions are provided.

  20. Large intracranial vessel occlusion arising after radiotherapy for craniopharingioma. A case report and review of the literature

    International Nuclear Information System (INIS)

    We report a patient who developed occlusion of the intracranial major arteries induced by radiation therapy for craniopharyngioma. The patient, a 9-year-old boy, presented with deterioration of vision, nausea and vomiting. He underwent a right ventriculo-peritoneal shunt operation, and the tumor was partially removed. Postoperatively, he received focal radiation therapy with total of 60 Gy. Preoperative cerebral angiography, cerebral vessels had no sigh of occlusive lesion or stenosis. One year after irradiation, he started to have repeated cerebral ischemic attacks. But no regrowth of the tumor was detected on CT scans. Two years and 8 months after irradiation, he suddenly had right hemiparesis. Cerebral angiography revealed severe stenosis of the right anterior cerebral artery (precommunicating segment), middle cerebral artery (horizontal portion) and terminal portion of the right carotid artery. Left carotid angiography showed complete occlusion of the terminal portion of the internal carotid artery and collateral vessels from the middle meningeal artery to the middle cerebral artery through the shunt burr hole. He has been treated conservatively and is doing well except for slight right hemiparesis. Our experience shows that the risk of occlusive cerebrovasculopathy after radiation therapy should be taken into account, especially in children. (author)

  1. Cerebral malformations without antenatal diagnosis

    International Nuclear Information System (INIS)

    Cerebral malformations are usually described following the different steps in development. Disorders of neurulation (dysraphisms), or diverticulation (holoprosencephalies and posterior fossa cysts), and total commissural agenesis are usually diagnosed in utero. In contrast, disorders of histogenesis (proliferation-differentiation, migration, organization) are usually discovered in infants and children. The principal clinical symptoms that may be a clue to cerebral malformation include congenital hemiparesis, epilepsy and mental or psychomotor retardation. MRI is the imaging method of choice to assess cerebral malformations. (orig.)

  2. Cerebral malformations without antenatal diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Girard, Nadine J. [Diagnostic Neuroradiology, Hopital Timone, Marseille (France)

    2010-06-15

    Cerebral malformations are usually described following the different steps in development. Disorders of neurulation (dysraphisms), or diverticulation (holoprosencephalies and posterior fossa cysts), and total commissural agenesis are usually diagnosed in utero. In contrast, disorders of histogenesis (proliferation-differentiation, migration, organization) are usually discovered in infants and children. The principal clinical symptoms that may be a clue to cerebral malformation include congenital hemiparesis, epilepsy and mental or psychomotor retardation. MRI is the imaging method of choice to assess cerebral malformations. (orig.)

  3. Neuroimaging findings in children with retinopathy-confirmed cerebral malaria

    International Nuclear Information System (INIS)

    Purpose: To describe brain CT findings in retinopathy-confirmed, paediatric cerebral malaria. Materials and methods: In this outcomes study of paediatric cerebral malaria, a subset of children with protracted coma during initial presentation was scanned acutely. Survivors experiencing adverse neurological outcomes also underwent a head CT. All children had ophthalmological examination to confirm the presence of the retinopathy specific for cerebral malaria. Independent interpretation of CT images was provided by two neuroradiologists. Results: Acute brain CT findings in three children included diffuse oedema with obstructive hydrocephalus (2), acute cerebral infarctions in multiple large vessel distributions with secondary oedema and herniation (1), and oedema of thalamic grey matter (1). One child who was reportedly normal prior to admission had parenchymal atrophy suggestive of pre-existing CNS injury. Among 56 survivors (9-84 months old), 15 had adverse neurologic outcomes-11/15 had a follow-up head CT, 3/15 died and 1/15 refused CT. Follow-up head CTs obtained 7-18 months after the acute infection revealed focal and multifocal lobar atrophy correlating to regions affected by focal seizures during the acute infection (5/11). Other findings were communicating hydrocephalus (2/11), vermian atrophy (1/11) and normal studies (3/11). Conclusions: The identification of pre-existing imaging abnormalities in acute cerebral malaria suggests that population-based studies are required to establish the rate and nature of incidental imaging abnormalities in Malawi. Children with focal seizures during acute cerebral malaria developed focal cortical atrophy in these regions at follow-up. Longitudinal studies are needed to further elucidate mechanisms of CNS injury and death in this common fatal disease.

  4. Neuroimaging findings in children with retinopathy-confirmed cerebral malaria

    Energy Technology Data Exchange (ETDEWEB)

    Potchen, Michael J. [Michigan State University, Department of Radiology, 184 Radiology Building, East Lansing, MI 48824-1303 (United States)], E-mail: mjp@rad.msu.edu; Birbeck, Gretchen L. [Michigan State University, International Neurologic and Psychiatric Epidemiology Program, 324 West Fee Hall, East Lansing, MI 48824 (United States)], E-mail: Gretchen.Birbeck@ht.msu.edu; DeMarco, J. Kevin [Michigan State University, Department of Radiology, 184 Radiology Building, East Lansing, MI 48824-1303 (United States)], E-mail: jkd@rad.msu.edu; Kampondeni, Sam D. [University of Malawi, Department of Radiology, Queen Elizabeth Central Hospital, Blantyre (Malawi)], E-mail: kamponde@msu.edu; Beare, Nicholas [St. Paul' s Eye Unit, Royal Liverpool University Hospital, Prescot Street, Liverpool L7 8XP (United Kingdom)], E-mail: nbeare@btinternet.com; Molyneux, Malcolm E. [Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine (Malawi); School of Tropical Medicine, University of Liverpool, Liverpool (United Kingdom)], E-mail: mmolyneux999@google.com; Taylor, Terrie E. [Michigan State University, College of Osteopathic Medicine, B309-B West Fee Hall, East Lansing, MI 48824 (United States); University of Malawi, College of Medicine, Blantyre Malaria Project, Blantyre (Malawi)], E-mail: taylort@msu.edu

    2010-04-15

    Purpose: To describe brain CT findings in retinopathy-confirmed, paediatric cerebral malaria. Materials and methods: In this outcomes study of paediatric cerebral malaria, a subset of children with protracted coma during initial presentation was scanned acutely. Survivors experiencing adverse neurological outcomes also underwent a head CT. All children had ophthalmological examination to confirm the presence of the retinopathy specific for cerebral malaria. Independent interpretation of CT images was provided by two neuroradiologists. Results: Acute brain CT findings in three children included diffuse oedema with obstructive hydrocephalus (2), acute cerebral infarctions in multiple large vessel distributions with secondary oedema and herniation (1), and oedema of thalamic grey matter (1). One child who was reportedly normal prior to admission had parenchymal atrophy suggestive of pre-existing CNS injury. Among 56 survivors (9-84 months old), 15 had adverse neurologic outcomes-11/15 had a follow-up head CT, 3/15 died and 1/15 refused CT. Follow-up head CTs obtained 7-18 months after the acute infection revealed focal and multifocal lobar atrophy correlating to regions affected by focal seizures during the acute infection (5/11). Other findings were communicating hydrocephalus (2/11), vermian atrophy (1/11) and normal studies (3/11). Conclusions: The identification of pre-existing imaging abnormalities in acute cerebral malaria suggests that population-based studies are required to establish the rate and nature of incidental imaging abnormalities in Malawi. Children with focal seizures during acute cerebral malaria developed focal cortical atrophy in these regions at follow-up. Longitudinal studies are needed to further elucidate mechanisms of CNS injury and death in this common fatal disease.

  5. Inhibitory effect of acupuncture on neuronal apoptosis in rats after cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Bangyu Ju; Jing Zhang; Guohua Jiang

    2007-01-01

    BACKGROUND: Delayed neuronal death after total cerebral ischemia may accompany with apoptosis, but acupuncture may play a certain role in protecting nerve through inhibiting ischemic neuronal apoptosis.OBJECTIVE: To observe the effect of acupuncture on neuronal apoptosis in rats after cerebral ischemia and analyze its cerebral protective mechanism.DESIGN: Contrast observation among groups.SETTING: Heilongjiang University of Traditional Chinese Medicine.MATERIALS: A total of 30 male healthy Wistar rats of general grade and weighing (250±20) g were randomly divided into three groups, including sham operation group, cerebral ischemia group and acupuncture group with 10 rats in each group. Apoptosis in situ kit was provided by Baolingman Company,Germany.METHODS: The experiment was carried out in the Laboratory Center, Heilongjiang University of Traditional Chinese Medicine from May to November 2004. ① Rats in the cerebral ischemia group and the acupuncture group were used to establish total cerebral ischemic models with four vessels occlusion; in addition, models in the sham operation group were established with the same method as mentioned above.However, four vessels of rats in the sham operation were exposured and cerebral ischemia did not occur. Rats in the acupuncture group were given acupuncture treatment after operation. Needle of 40 mm in length was used to acupuncture bilateral Zusanli (St 36) and Quchi (LI 11) with the depth of 3 mm, and then bilateral acupoints were connected with KWD-808Ⅱ omnipotenc impulse electro-therapeutic apparatus (frequency: 1 Hz;thin waves; voltage: 2 V) once a day for totally 30 minutes. Meanwhile, needle of 25 mm in length was used to acupuncture Baihui (Du 20) with the depth of 3 mm, and then the needle was twirled once every 5 minutes for 30 minutes in total. The course was 7 days. ② Neuronal injuries in hippocampal CA1 area after cerebral ischemia were observed with Nissl body staining method at 7 days after treatment

  6. New possibilities for quantitative measurements of regional cerebral blood flow with gold-195m

    International Nuclear Information System (INIS)

    A previously reported theory for quantitative cerebral blood flow measurement for nondiffusible radiotracers has been applied to patients after stroke and to volunteers undergoing a mental stimulation exercise. The energy spectrum of gold-195m shows two strong photon peaks, one at an energy level of 68 keV and a second at an energy-level of 262 keV. The low energy peak is suitable for perfusion studies in lateral views of the hemispheres; no look-through effect is seen. The high energy level is good for studies in posterior-anterior positions. Parametric images for quantitative regional cerebral blood flow can be generated. The area of occluded vessels in the case of stroke can be detected. Quantitative activation patterns of cerebral blood flow during mental stimulation can be generated. The results prove that, not only with freely diffusible indicators like xenon but also with nondiffusible indicators, it is possible to measure quantitatively cerebral blood flow patterns

  7. The CT manifestations and clinical analysis of traumatic cerebral infarction in children

    International Nuclear Information System (INIS)

    Objective: To evaluate pathogenesis, CT manifestations, diagnosis and treatment, and prognosis of traumatic cerebral infarction in children. Methods: Axial head CT scanning was performed in 35 cases, meanwhile the treatment included vessel dilatation, anti-spasm, nerve nourishment and anti-coagulation. Results: The traumatic cerebral infarction in children was commonly located in the basal ganglia. CT scan revealed low dense lesions in all cases. 33 patients out of 35 convalesced gradually, when no anomaly was shown on CT. The rest 2 patients improved, whose lesions decreased in size on CT images. Conclusion: The major pathophysiology of traumatic cerebral infarction in children is occlusion of cerebral microcirculation and convulsion of vein after trauma. CT scan and follow-up are of great value in monitoring the damages. Early diagnosis and treatment result in good prognosis

  8. MR angiographic and parenchymal evaluation of cerebral infaraction in sickle cell anemia

    International Nuclear Information System (INIS)

    Cerebral infarction is an important complication of sickle cell anemia, believed to be related to large-vessel stenoses/occlusion and/or capillary/venous sickling resulting in thrombosis. Identification of these complications (especially large-vessel arterial disease) is important in selecting patients for transfusion therapy. The purpose of this study was to determine the suitability of combined three-dimensional Fourier transform time-of-flight MR angiographic and parenchymal T2-weighted spin-echo examinations for evaluation of central nervous system (CNS) complications of sickle cell anemia. Seven patients (age range, 5-14 years) were evaluated. Five had documented strokes while two had symptoms resembling those of transient ischemic attack. The preliminary data indicate that combined MR angiographic and parenchymal studies are capable of identifying those patients with sickle cell anemia complicated by large-vessel CNS occlusive disease and cerebral infarction and can be used as a noninvasive guide to therapy

  9. Mechanics and composition of middle cerebral arteries from simulated microgravity rats with and without 1-h/d -Gx gravitation.

    Directory of Open Access Journals (Sweden)

    Jiu-Hua Cheng

    Full Text Available BACKGROUND: To elucidate further from the biomechanical aspect whether microgravity-induced cerebral vascular mal-adaptation might be a contributing factor to postflight orthostatic intolerance and the underlying mechanism accounting for the potential effectiveness of intermittent artificial gravity (IAG in preventing this adverse effect. METHODOLOGY/PRINCIPAL FINDINGS: Middle cerebral arteries (MCAs were isolated from 28-day SUS (tail-suspended, head-down tilt rats to simulate microgravity effect, S+D (SUS plus 1-h/d -Gx gravitation by normal standing to simulate IAG, and CON (control rats. Vascular myogenic reactivity and circumferential stress-strain and axial force-pressure relationships and overall stiffness were examined using pressure arteriography and calculated. Acellular matrix components were quantified by electron microscopy. The results demonstrate that myogenic reactivity is susceptible to previous pressure-induced, serial constrictions. During the first-run of pressure increments, active MCAs from SUS rats can strongly stiffen their wall and maintain the vessels at very low strains, which can be prevented by the simulated IAG countermeasure. The strains are 0.03 and 0.14 respectively for SUS and S+D, while circumferential stress being kept at 0.5 (106 dyn/cm2. During the second-run pressure steps, both the myogenic reactivity and active stiffness of the three groups declined. The distensibility of passive MCAs from S+D is significantly higher than CON and SUS, which may help to attenuate the vasodilatation impairment at low levels of pressure. Collagen and elastin percentages were increased and decreased, respectively, in MCAs from SUS and S+D as compared with CON; however, elastin was higher in S+D than SUS rats. CONCLUSIONS: Susceptibility to previous myogenic constrictions seems to be a self-limiting protective mechanism in cerebral small resistance arteries to prevent undue cerebral vasoconstriction during orthostasis at 1-G

  10. Navigation system for Finnish oil recovery vessel

    International Nuclear Information System (INIS)

    Finland's National Board of Waters and the Environment (FNBWE) and the Finnish electronics company Jertec Oy have together developed a computer-based oil recovery system to improve the efficiency of oil recovery operations in the Baltic Sea. The Baltic Sea is extremely vulnerable to oil spills, largely because at high latitudes there are only a few hours of daylight during winter. Integration of the ship's navigational equipment with a highly accurate positioning system such as the differential GPS makes it possible to operate 24 hours a day. Also, oil recovery can be made much more efficient by using a new technique to collect oil from a wider area than at present. The oil recovery vessel Halli has a length of 60 meters and is capable of recovering oil either alone or with two assisting vessels. In the latter case, the assisting vessels draw oil booms to direct floating oil from a wide area into the Halli rather like a funnel. Previously, this operation was limited to straight runs and daylight hours. The Halli is also equipped to perform underwater investigations (such as seabed wrecks) with a small submersible. Without an underwater positioning and tracking system, underwater operations are inefficient. The main requirements for the new system were reliable positioning of all vessels (assisting vessels are not known in advance), reliable inter-vessel communication, and documentation and printouts of the planned and real routes. The new navigation system was installed in November 1991 and has since fulfilled all FNBWE's requirements. The main benefit is the capability to operate 24 hours a day, which greatly increases the efficiency of oil recovery

  11. Human cerebral malaria and Plasmodium falciparum genotypes in Malawi

    Directory of Open Access Journals (Sweden)

    Milner Danny A

    2012-02-01

    Full Text Available Abstract Background Cerebral malaria, a severe form of Plasmodium falciparum infection, is an important cause of mortality in sub-Saharan African children. A Taqman 24 Single Nucleotide Polymorphisms (SNP molecular barcode assay was developed for use in laboratory parasites which estimates genotype number and identifies the predominant genotype. Methods The 24 SNP assay was used to determine predominant genotypes in blood and tissues from autopsy and clinical patients with cerebral malaria. Results Single genotypes were shared between the peripheral blood, the brain, and other tissues of cerebral malaria patients, while malaria-infected patients who died of non-malarial causes had mixed genetic signatures in tissues examined. Children with retinopathy-positive cerebral malaria had significantly less complex infections than those without retinopathy (OR = 3.7, 95% CI [1.51-9.10].The complexity of infections significantly decreased over the malaria season in retinopathy-positive patients compared to retinopathy-negative patients. Conclusions Cerebral malaria patients harbour a single or small set of predominant parasites; patients with incidental parasitaemia sustain infections involving diverse genotypes. Limited diversity in the peripheral blood of cerebral malaria patients and correlation with tissues supports peripheral blood samples as appropriate for genome-wide association studies of parasite determinants of pathogenicity.

  12. Vasculite cutânea de pequenos vasos: etiologia, patogênese, classificação e critérios diagnósticos - Parte I Small vessel cutaneous vasculitis: etiology, pathogenesis, classification and diagnostic criteria - Part I

    Directory of Open Access Journals (Sweden)

    Hebert Roberto Clivati Brandt

    2007-10-01

    Full Text Available Vasculite é a inflamação da parede dos vasos. Pode variar em gravidade desde doença autolimitada de um único órgão até doença grave com risco de morte por falência de múltiplos órgãos. Existem várias causas, embora só se apresente por poucos padrões histológicos de inflamação vascular. Vasos de qualquer tipo e em qualquer órgão podem ser afetados, resultando em ampla variedade de sinais e sintomas. Diferentes vasculites com apresentações clínicas indistinguíveis têm evolução e tratamento muito diferentes. Essa condição representa desafio para o médico, incluindo classificação, diagnóstico, exames laboratoriais pertinentes, tratamento e seguimento adequado. Neste artigo são revistos a classificação, a etiologia, a patogênese e os critérios diagnósticos das vasculites cutâneas.Vasculitis is an inflammation of vessel walls. It may range in severity from a self-limited disorder in one single organ to a life-threatening disease due to multiple-organ failure. It has many causes, although they result in only a few histological patterns of vascular inflammation. Vessels of any type in any organ can be affected, a fact that results in a broad variety of signs and symptoms. Different vasculitides with indistinguishable clinical presentations have very different prognosis and treatments. This condition presents many challenges to physicians in terms of classification, diagnosis, appropriate laboratory workup, treatment, and the need for careful follow-up. This article reviews the classification, etiology, pathology and diagnostic criteria of cutaneous vasculitis.

  13. Assessment of variability in cerebral vasculature for neuro-anatomical surgery planning in rodent brain

    Science.gov (United States)

    Rangarajan, J. R.; Van Kuyck, K.; Himmelreich, U.; Nuttin, B.; Maes, F.; Suetens, P.

    2011-03-01

    Clinical and pre-clinical studies show that deep brain stimulation (DBS) of targeted brain regions by neurosurgical techniques ameliorate psychiatric disorder such as anorexia nervosa. Neurosurgical interventions in preclinical rodent brain are mostly accomplished manually with a 2D atlas. Considering both the large number of animals subjected to stereotactic surgical experiments and the associated imaging cost, feasibility of sophisticated pre-operative imaging based surgical path planning and/or robotic guidance is limited. Here, we spatially normalize vasculature information and assess the intra-strain variability in cerebral vasculature for a neurosurgery planning. By co-registering and subsequently building a probabilistic vasculature template in a standard space, we evaluate the risk of a user defined electrode trajectory damaging a blood vessel on its path. The use of such a method may not only be confined to DBS therapy in small animals, but also could be readily applicable to a wide range of stereotactic small animal surgeries like targeted injection of contrast agents and cell labeling applications.

  14. Adrenergic receptor subtypes in the cerebral circulation of newborn piglets

    International Nuclear Information System (INIS)

    The purpose of this study was to identify the α-adrenergic receptor subtype mediating cerebral vasoconstriction during sympathetic nerve stimulation in the newborn piglet. The effect of α1- and α2-antagonists prazosin and yohimbine on the cerebrovascular response to unilateral electrical stimulation (15 Hz, 15 V) of the superior cervical sympathetic trunk was studied in 25 newborn piglets. Regional cerebral blood flow was measured with tracer microspheres. Sympathetic stimulation decreased blood flow to the ipsilateral cerebrum hippocampus, choroid plexus, and masseter muscle. α1-Adrenergic receptor blockade with prazosin inhibited the sympathetic vasoconstriction in the cerebrum, hippocampus, and masseter muscle and abolished it in the choroid plexus. α/sub s/-Adrenergic receptor blockade with yohimbine had no effect. Following the higher dose of yohimbine, however, blood flow to all brain regions was increased by approximately two-fold, possibly due to enhanced cerebral metabolism. These data demonstrate that vascular α1-adrenergic receptors mediate vasoconstriction to neuroadrenergic stimulation in cerebral resistance vessels in the newborn piglet

  15. Intravenous DSA as a screening method for cerebral aneurysms

    International Nuclear Information System (INIS)

    Intravenous DSA (IVDSA) was evaluated as a screening method for cerebral aneurysms. It was performed 390 times in 372 cases. Clinically useful images were obtained in 94.1% in all examinations. Nineteen aneurysms were visualized in cerebral angiography among 21 cases with SAH or 3rd nerve palsy, whereas in IVDSA 15 aneurysms were noted. Aneurysms not visualized in IVDSA were all 4 mm or less in size. Therefore, aneurysms, more than 4 mm in size, which have higher risks for rupture, were detectable in IVDSA. Based on these findings, IVDSA is considered to be clinically useful in screening for aneurysms. In all 372 cases, 33 aneurysms were suspected in IVDSA findings, whereas in cerebral angiography 21 of them turned to be aneurysms. Such 12 false positive cases were distributed mainly at anterior communicating and middle cerebral arteries. Improvement of image resolution, avoidance of vessel overlapping and proper selection of screened cases should be investigated for further development of this screening method. (author)

  16. Guidelines for the pressure and efficient sizing of pressure vessels for compressed air energy storage

    International Nuclear Information System (INIS)

    Highlights: ► In small-scale CAES there are no robust guidelines in choosing an operational pressure for the vessels. ► Through the stress analysis of the vessel, an optimum pressure at minimum cost can be determined. ► One contribution is in determining the optimum pressure is small-scale CAES. ► Another contribution is in determining the shape size, and number of vessels in small-scale CAES designs. - Abstract: The paper reports guidelines for the efficient design and sizing of Small-Scale Compressed Air Energy Storage (SS-CAES) pressure vessels, including guidelines for pressures that should be used in the SS-CAES system to minimize the cost of the pressure vessel. Under a specified energy storage capacity and specified maximum and minimum operating pressures in CAES, the volume of the vessel(s) can be evaluated. The present study provides guidelines for choosing appropriate shape and size for the vessels that minimize material and manufacturing cost for cylindrical vessels. The two main contributions of the paper are that it provides a methodology to determine: (a) an optimum pressure; (b) the shape, size, and number of vessel to be used in a particular application. Results suggest that pressure vessels with a length to diameter ratio of roughly three are the most economical, and that a system should be designed for a pressure of roughly three times the minimum pressure of the expansion device.

  17. Occult cerebral vascular malformation: High-field (2.0 T) MR imaging and comparison with CT

    International Nuclear Information System (INIS)

    Extensive experience with CT has led to the recognition of criteria for the diagnosis of occult cerebral vascular malformation. MR demonstrated all lesions as hemorrhage foci. The most common and typical MR findings of OVCM was circumscribed thick hypointense rim on T2-weighted images (T2-Wls) representing hemosiderin deposit with various central intensities suggesting the presence of hematomas in different stages (11 lesions). Among these. the recurrent hemorrhage in small amount produced the characteristic 'a bunch of grape' appearance. But, small OCVM less than 1 cm in diameter was identified as a small homogeneous hypointense nodule on T2-Wls with sharp (6 lesions) or fade-out (1 lesions) border. There were 2 lesions showing atypical findings such as dense hemosiderin rin with central lacuma or bilobed subacute hematoma. As the associated MR findings which strongly suggest the diagnosis of OCVM signal void due to feeding or draining vessels was found in 4, lesions and the surrounding focal cortical atrophy or leukomalacia in 2 lesions. The predilection site of OCVM was subcortical (8 lesions) and periventricular (6 cases) location. CT depicted 16 of the 20 lesions, but missed 4 lesions of small OCVM. CT alone did not permit definitive diagnosis of OCVM is most cases. Fifteen lesions demonstrated on CT contained somewhat hyperdense area in central or peripheral locations. Peripheral hyperdense area corresponded to the dense hemosiderin deposit on MR and central one to the hematoma formed by recent hemorrhage. Low density area on CT usually corresponded to liquefied subacute hematoma on MR

  18. Three-dimensional representation of vessels using pixel classification

    International Nuclear Information System (INIS)

    MR imaging has the ability to visualize blood flow noninvasively and without the use of contrast agents. The authors present a method based on pixel classification to distinguish between vessels and stationary tissue. Three-dimensional imaging methods are used. The user labels a small set of images containing both vessels and stationary tissue. These labeled images are used to train a numerical classifier. Each voxel is characterized by a feature vector containing information about voxel intensity, and relationships to neighboring voxels. Unlabeled images are transformed into probability images by multiplying the corresponding feature vector of each voxel by the calculated classification matrix. The probability images are used to decide whether a voxel belongs to stationary tissue or to vessels. The decision-making process results in a binary image that is used as a mask to extract a pure vessel image. This technique offers many possibilities for vessel display

  19. Anatomic variations of anterior cerebral artery cortical branches.

    Science.gov (United States)

    Stefani, M A; Schneider, F L; Marrone, A C; Severino, A G; Jackowski, A P; Wallace, M C

    2000-01-01

    The anterior cerebral artery (ACA) is a major vessel responsible for the blood supply to the interhemispheric region. The ACA segment after the anterior communicating artery (AComA) origin is called the distal ACA and has central and cortical branches. The cortical branches are distributed in the different regions of the orbital and medial part of the brain. The objects of this study are the anatomical variations found in the distal ACA. In 76 hemispheres the ACA distal branches were injected with latex and dissected under microscope magnification. Vessel diameters and distances between vessel origins and anterior communicating artery were recorded and analyzed. Microsurgical dissection was carried out to demonstrate anatomic variations of these vessels. Average diameter of ACA at origin was 2.61 +/- 0.34 mm and average diameter of cortical branches diameter ranged from 0.79 +/- 0.27 mm to 1.84 +/- 0.3 mm. Distances between vessel origin and AComA ranged from 7.68 +/- 3.91 mm (orbitofrontal) to 112.6 +/- 11.63 mm (inferior internal parietal). This study found anatomical variations: a single (azygos) ACA was present in one case and three in three cases. Crossing branches of the distal ACA to the contralateral hemisphere were present in 26% of the cases. In some cases a single ACA may supply the posterior hemispheric region through crossing branches. This calls attention to potential bilateral brain infarcts due to a single unilateral ACA occlusion. PMID:10873213

  20. Advances in the understanding of delayed cerebral ischaemia after aneurysmal subarachnoid haemorrhage [version 1; referees: 4 approved

    Directory of Open Access Journals (Sweden)

    Liam Flynn

    2015-11-01

    Full Text Available Delayed cerebral ischaemia has been described as the single most important cause of morbidity and mortality in patients who survive the initial aneurysmal subarachnoid haemorrhage. Our understanding of the pathophysiology of delayed cerebral ischaemia is meagre at best and the calcium channel blocker nimodipine remains the only intervention to consistently improve functional outcome after aneurysmal subarachnoid haemorrhage. There is substantial evidence to support cerebral vessel narrowing as a causative factor in delayed cerebral ischaemia, but contemporary research demonstrating improvements in vessel narrowing has failed to show improved functional outcomes. This has encouraged researchers to investigate other potential causes of delayed cerebral ischaemia, such as early brain injury, microthrombosis, and cortical spreading depolarisation. Adherence to a common definition of delayed cerebral ischaemia is needed in order to allow easier assessment of studies using multiple different terms. Furthermore, improved recognition of delayed cerebral ischaemia would not only allow for faster treatment but also better assessment of interventions. Finally, understanding nimodipine’s mechanism of action may allow us to develop similar agents with improved efficacy.

  1. Cerebral infarction: an unusual manifestation of viper snake bite

    Directory of Open Access Journals (Sweden)

    Jyotirmoy Pal

    2014-06-01

    Full Text Available Snake envenomation causes significant mortality and morbidity. Viper bite usually present with local cellulites, renal failure and bleeding disorders. Thrombotic manifestation of snake bite is rarely reported and early administration of Anti-Snake Venom Serum (ASV also reduces the risk of thrombotic complications. Cerebral infarction in case of viper bite may be due to hypotension, hypercoagulability or direct action of venom on vessel wall. We report a rare case of viper bite, presented with renal failure and cerebral infarction in spite of early ASV institution. The thrombotic manifestation in this case was possibly due to disseminated intravascular coagulation. [Int J Res Med Sci 2014; 2(3.000: 1180-1183

  2. [Neonatal cerebral thrombosis and deficit of factor V leiden].

    Science.gov (United States)

    Moliner Calderón, E; López Bernal, E; Ginovart Galiana, G; Nadal Amat, J; Cubells Riero, J

    2000-01-01

    Background Cerebral venous thrombosis is an inusual disease in neonatal age. Increasing reports of this disorder had described since magnetic resonance angiography is used. Case report Newborn of apropriate seze for gestational age was delivered at 35 weeks of gestation. Refered a severe hipoxic-isquemic disease with multisistemic afectation. The second day of life presented disseminated intravascular coagulation with pulmonary bleeding. The third day, the infant developed seizures that required treatment with diazepam in continuous perfussion. MR angiography visualized superior sagital and transvers sinus thrombosis. Coagulation study detected factor V Leiden. Comments Frecuently venous cerebral thrombosis is presenting with lethargy and seizures. The most common vessels involved are sagital and transvers sinus. It is described in association with exogenous risk factors that increasing blood hyperviscosity and additional inhered coagulation dissorders such as defects on antihrombina III, protein C and S and activate protein C resistance. The last defect has a hight prevalence in subjects with trombosis events. PMID:11003860

  3. PWR pressure vessel integrity during overcooling accidents

    International Nuclear Information System (INIS)

    Pressurized water reactors are susceptible to certain types of hypothetical accidents that under some circumstances, including operation of the reactor beyond a critical time in its life, could result in failure of the pressure vessel as a result of propagation of crack-like defects in the vessel wall. The accidents of concern are those that result in thermal shock to the vessel while the vessel is subjected to internal pressure. Such accidents, referred to as pressurized thermal shock or overcooling accidents (OCA), include a steamline break, small-break LOCA, turbine trip followed by stuck-open bypass valves, the 1978 Rancho Seco and the TMI accidents and many other postulated and actual accidents. The source of cold water for the thermal shock is either emergency core coolant or the normal primary-system coolant. ORNL performed fracture-mechanics calculations for a steamline break in 1978 and for a turbine-trip case in 1980 and concluded on the basis of the results that many more such calculations would be required. To meet the expected demand in a realistic way a computer code, OCA-I, was developed that accepts primary-system temperature and pressure transients as input and then performs one-dimensional thermal and stress analyses for the wall and a corresponding fracture-mechanics analysis for a long axial flaw. The code is briefly described, and its use in both generic and specific plant analyses is discussed

  4. Stress criteria for nuclear vessel concrete

    International Nuclear Information System (INIS)

    Concrete nuclear vessels are submitted to prestressing forces which limit tensile stresses in concrete when the vessel is under pressure with thermal gradients. Hence, the most severe conditions for concrete appear when the vessel is prestressed and not submitted to internal pressure. The triaxial states of stress in the concrete may be computed postulating elastic or other behavior and compared with safe limits obtained from rupture tests and fatigue tests. The first part of the paper, recalls experimental rupture results and the acceptability procedures currently used. Criteria founded on the lemniscoid surfaces are proposed, parameters for which are obtained by various tests and safety considerations. In the second part, rupture tests are reported on small, thick, cylindrical vessels submitted to external hydraulic pressure simulating prestressing forces. Materials used are plain concrete, microconcrete, marble and graphite. The strengths obtained are much higher than those which could be elastically computed, triaxial rupture states being provided by previous experiments. Such results may be due to a plastic stress redistribution before fracture and to stabilizing effects of stress gradients around the more stressed areas. Fatigue tests by external hydraulic loading are reported

  5. Cerebral oxygenation after birth

    DEFF Research Database (Denmark)

    Hessel, Trine W; Hyttel-Sorensen, Simon; Greisen, Gorm

    2014-01-01

    AIM: To compare absolute values of regional cerebral tissue oxygenation (cStO2 ) during haemodynamic transition after birth and repeatability during steady state for two commercial near-infrared spectroscopy (NIRS) devices. METHODS: In a prospective observational study, the INVOS 5100C and FORE...... INVOS and FORE-SIGHT cStO2 estimates showed oxygenation-level-dependent difference during birth transition. The better repeatability of FORE-SIGHT could be due to the lower response to change in saturation....

  6. Techniques in cerebral protection

    International Nuclear Information System (INIS)

    Carotid angioplasty and stenting is a valid alternative option to conventional carotid endarterectomy in the treatment of carotid artery stenosis. During the stenting process, however, distal embolization can occur with neurological consequences. To avoid this, cerebral protection devices have been introduced. Three principal types of protection system have been developed: distal balloon occlusion, distal filters and proximal protection with or without reversal of flow. As protection devices became the focus of interest by manufactures and physicians, several trials are going on worldwide to analyze the characteristics of each of them and to evaluate their efficacy to reduce the rate of distal embolization

  7. Vessel enhancing diffusion: a scale space representation of vessel

    OpenAIRE

    Manniesing, Rashindra; Viergever, M.A; Niessen, Wiro

    2006-01-01

    textabstractA method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffus...

  8. Dynamic cerebral autoregulation during repeated squat-stand maneuvers.

    NARCIS (Netherlands)

    Claassen, J.A.H.R.; Levine, B.D.; Zhang, R.

    2009-01-01

    Transfer function analysis of spontaneous oscillations in blood pressure (BP) and cerebral blood flow (CBF) can quantify the dynamic relationship between BP and CBF. However, such oscillation amplitudes are often small and of questionable clinical significance, vary substantially, and cannot be cont

  9. Therapeutic interventions in cerebral palsy.

    Science.gov (United States)

    Patel, Dilip R

    2005-11-01

    Various therapeutic interventions have been used in the management of children with cerebral palsy. Traditional physiotherapy and occupational therapy are widely used interventions and have been shown to be of benefit in the treatment of cerebral palsy. Evidence in support of the effectiveness of the neurodevelopmental treatment is equivocal at best. There is evidence to support the use and effectiveness of neuromuscular electrical stimulation in children with cerebral palsy. The effectiveness of many other interventions used in the treatment of cerebral palsy has not been clearly established based on well-controlled trials. These include: sensory integration, body-weight support treadmill training, conductive education, constraint-induced therapy, hyperbaric oxygen therapy, and the Vojta method. This article provides an overview of salient aspects of popular interventions used in the management of children with cerebral palsy. PMID:16391455

  10. Cerebral hemodynamics in moyamoya disease

    International Nuclear Information System (INIS)

    Rebuild-up phenomenon, an electroencephalographic pathological finding in moyamoya disease, was evaluated in the context of dynamic changes in cerebral circulation after hyperventilation. Sequential functional angiography after hyperventilation, measurement of cerebral blood flow (CBF) by the outflow method, and Kr-81m single photon emission tomography were employed for clarification of the sequential dynamic changes in cerebral circulation after hyperventilation. In most cases there was a persistent decrease in CBF even after arterial carbon dioxide tension (PaCO2) had been normalized, which suggests that the response of the cerebral circulation to the changes in PaCO2 is delayed. Moreover, this feature was most prominent in the superficial layer of the cerebrum. For the most part, coincidence and synchronization were documented between rebuild-up and the delayed response of the cerebral circulation. These findings indicate that the delayed CBF response to hyperventilation contributes pathogenetically to rebuild-up in moyamoya disease. (author)

  11. Cerebral Hemorrhage and APOE genotype

    Institute of Scientific and Technical Information of China (English)

    Sun xiaojiang; Wu ping; Zhang jing; Lu shanqing; Li bing

    2000-01-01

    Background and Purpose: Current evidence Suggests that the apolipoprotein E (APOE)ε 4 allele predisposes to cerebral amyloid angiopathy (CAA) whereas ε 2 is associated with CAA-zelated hemorrhage. In this study we examined potential clinical risk factors inpatients with cerebral hemorrhage and assessed these with respect to APOE genotype. Methoeds: 146 patinas with cerebral hemorrhage and 70 normal controls were investigated. APOE genotypes were determined with use of polymerase Chain reaction techniques.Results: The frequency of allele gene ( 0.180 ) and the percentage of the APOE ε 4 genotype in the cerebral hemorrhage group were Significantly higher as compared with the e 4 prequency ( O.O72 ) in the control group respectively ( p=O.O389 ) .Conelusious: APOE ε 4 :allele is a risk gene for cerebral hemorrhage.

  12. Summary of Reported Whale-Vessel Collisions in Alaskan Waters

    Directory of Open Access Journals (Sweden)

    Janet L. Neilson

    2012-01-01

    Full Text Available Here we summarize 108 reported whale-vessel collisions in Alaska from 1978–2011, of which 25 are known to have resulted in the whale's death. We found 89 definite and 19 possible/probable strikes based on standard criteria we created for this study. Most strikes involved humpback whales (86% with six other species documented. Small vessel strikes were most common (<15 m, 60%, but medium (15–79 m, 27% and large (≥80 m, 13% vessels also struck whales. Among the 25 mortalities, vessel length was known in seven cases (190–294 m and vessel speed was known in three cases (12–19 kn. In 36 cases, human injury or property damage resulted from the collision, and at least 15 people were thrown into the water. In 15 cases humpback whales struck anchored or drifting vessels, suggesting the whales did not detect the vessels. Documenting collisions in Alaska will remain challenging due to remoteness and resource limitations. For a better understanding of the factors contributing to lethal collisions, we recommend (1 systematic documentation of collisions, including vessel size and speed; (2 greater efforts to necropsy stranded whales; (3 using experienced teams focused on determining cause of death; (4 using standard criteria for validating collision reports, such as those presented in this paper.

  13. In-vessel safety in the ITER-EDA design

    Energy Technology Data Exchange (ETDEWEB)

    Bartels, H.W. [ITER San Diego JWS, La Jolla, CA (United States); Chuyanov, V. [ITER San Diego JWS, La Jolla, CA (United States); Holland, D. [ITER San Diego JWS, La Jolla, CA (United States)]|[ITER Naka JWS, Ibaraki (Japan); Kashirski, A. [ITER San Diego JWS, La Jolla, CA (United States); Morozov, S. [ITER San Diego JWS, La Jolla, CA (United States); Piet, S. [ITER San Diego JWS, La Jolla, CA (United States); Poucet, A. [ITER San Diego JWS, La Jolla, CA (United States); Saji, G. [ITER San Diego JWS, La Jolla, CA (United States); Topilski, L. [ITER San Diego JWS, La Jolla, CA (United States)

    1995-12-31

    A survey of important in-vessel safety features of ITER is presented. The experimental nature of the in-vessel components and the uncertainties connected with plasma physics lead to the approach to minimize safety credit for these issues. Safety analysis include the assumption of complete failure of coolant systems inside the vessel and most conservative estimations of the source terms produced during plasma disruptions. First results obtained from scoping studies lead to the expectation that within conservative assumptions the small energy inventories connected with the plasma and decay heat could not threaten the public. (orig.).

  14. In-vessel safety in the ITER-EDA design

    International Nuclear Information System (INIS)

    A survey of important in-vessel safety features of ITER is presented. The experimental nature of the in-vessel components and the uncertainties connected with plasma physics lead to the approach to minimize safety credit for these issues. Safety analysis include the assumption of complete failure of coolant systems inside the vessel and most conservative estimations of the source terms produced during plasma disruptions. First results obtained from scoping studies lead to the expectation that within conservative assumptions the small energy inventories connected with the plasma and decay heat could not threaten the public. (orig.)

  15. Quality assurance of the reactor pressure vessel of nuclear power plants. Determination of the fracture toughness KIC above the ductile-brittle transition region on small test specimens by means of a conformal mapping

    International Nuclear Information System (INIS)

    The ''surveillance-programs'' for the determination of the mechanical properties of reactor pressure vessel (RPV) materials, as a function of the neutron dose, include impact and tensile tests for the boiling water reactor; while for pressurized water reactors additional wedge opening load specimens (WOL), for the measurement of the fracture toughness KIC at low temperatures, are utilized. While the Charpy impact toughness gives the total magnitude of energy, which indicates the change of the material state, e.g. the state of embrittlement, the fracture toughness, IIC, gives a base for mechanical calculations. This is of importance for components in which cracks or flaws are assumed. The mechanical analysis, and its relevance to safety assessments, depends on the knowledge of different parameters such as geometry of the structure and flaws, and load history of the structure. Fracture mechanical methods play an important role, if the leak-before-fracture problem is considered. Within the frame work of fracture mechanical methods, only the influence of assumed macroscopic cracks on the structural behaviour can be handled. Flaw formation processes in flaw-free structures, as well as the treatment of short flaws, can not currently be included. In the regime of low and intermediate temperatures (for ferritic and austenitic materials, normally below 400oC), the rules of linear elastic fracture mechanics (LEFM) and elasto-plastic fracture mechanics (EPFM) are applied, some of which are already part of the code cases. (author) 5 figs., 32 refs

  16. NADPH oxidase 4 attenuates cerebral artery changes during the progression of Marfan syndrome.

    Science.gov (United States)

    Onetti, Yara; Meirelles, Thayna; Dantas, Ana P; Schröder, Katrin; Vila, Elisabet; Egea, Gustavo; Jiménez-Altayó, Francesc

    2016-05-01

    Marfan syndrome (MFS) is a connective tissue disorder that is often associated with the fibrillin-1 (Fbn1) gene mutation and characterized by cardiovascular alterations, predominantly ascending aortic aneurysms. Although neurovascular complications are uncommon in MFS, the improvement in Marfan patients' life expectancy is revealing other secondary alterations, potentially including neurovascular disorders. However, little is known about small-vessel pathophysiology in MFS. MFS is associated with hyperactivated transforming growth factor (TGF)-β signaling, which among numerous other downstream effectors, induces the NADPH oxidase 4 (Nox4) isoform of NADPH oxidase, a strong enzymatic source of H2O2 We hypothesized that MFS induces middle cerebral artery (MCA) alterations and that Nox4 contributes to them. MCA properties from 3-, 6-, or 9-mo-old Marfan (Fbn1(C1039G/+)) mice were compared with those from age/sex-matched wild-type littermates. At 6 mo, Marfan compared with wild-type mice developed higher MCA wall/lumen (wild-type: 0.081 ± 0.004; Marfan: 0.093 ± 0.002; 60 mmHg; P Marfan mice with Nox4 deficiency (Nox4(-/-)). Strikingly, Nox4 deletion in Marfan mice aggravated MCA wall thickening (cross-sectional area; Marfan: 6,660 ± 363 μm(2); Marfan Nox4(-/-): 8,795 ± 824 μm(2); 60 mmHg; P < 0.05), accompanied by decreased TGF-β expression and increased collagen deposition and Nox1 expression. These findings provide the first evidence that Nox4 mitigates cerebral artery structural changes in a murine model of MFS. PMID:26945079

  17. [Medullary venous malformation with azygos anterior cerebral artery aneurysm: a case report].

    Science.gov (United States)

    Harada, K; Kobayashi, S; Sigemori, M; Watanabe, M; Kuramoto, S

    1987-03-01

    A case of medullary venous malformation with azygos anterior cerebral artery aneurysm is reported, which was associated with the leptomenigeal angiomatosis on the cortex of the right frontal lobe. A 62-year-old female was admitted to the Kurume University Hospital on June 21, 1985, because of a convulsive seizure. On admission, neurological and general examinations, except for slightly liver function disorder, was no abnormality. Plain CT scan showed the cortical atrophy and two small high-density areas in the right frontal lobe. Enhanced CT scan showed a high-density area in the genu of the corpus callosum. MRI (magnetic resonance imaging), on T2 weighted image, showed a high signal intensity area in the right paraventricular deep white matter and the right frontal region. A right internal carotid angiogram in the venous phase showed numerous enlarged medullary veins in the deep frontal region, converging into a single large draining vein that empties into the basal vein of Rosenthal. An azygos anterior cerebral artery was visualized on the right and left carotid angiograms. The aneurysm was situated at the distal end of the azygos artery. Twenty eight days after admission, a right frontal cranioplastic craniotomy was performed. During operation, the surface of the right frontal lobe was covered by fine, vascular networks, which was reddish brown. A right frontal lobectomy, including venous malformation and vascular networks, was performed. The aneurysm was clipped via an interhemispheric approach. Histologically, the malformation vessels had spread into the subarachnoid space.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3600991

  18. A simple technique for morphological measurement of cerebral arterial circle variations using public domain software (Osiris).

    Science.gov (United States)

    Ansari, Saeed; Dadmehr, Majid; Eftekhar, Behzad; McConnell, Douglas J; Ganji, Sarah; Azari, Hassan; Kamali-Ardakani, Shahab; Hoh, Brian L; Mocco, J

    2011-12-01

    This article describes a straightforward method to measure the dimensions and identify morphological variations in the cerebral arterial circle using the general-purpose software program Osiris. This user-friendly and portable program displays, manipulates, and analyzes medical digital images, and it has the capability to determine morphometric properties of selected blood vessels (or other anatomical structures) in humans and animals. To ascertain morphometric variations in the cerebral arterial circle, 132 brains of recently deceased fetuses, infants, and adults were dissected. The dissection procedure was first digitized, and then the dimensions were measured with Osiris software. Measurements of each vessel's length and external diameters were used to identify and classify morphological variations in the cerebral arterial circle. The most commonly observed anatomical variations were uni- and bilateral hypoplasia of the posterior communicating artery. This study demonstrates that public domain software can be used to measure and classify cerebral arterial circle vessels. This method could be extended to examine other anatomical regions or to study other animals. Additionally, knowledge of variations within the circle could be applied clinically to enhance diagnostic and treatment specificity. PMID:22254161

  19. Cerebral involvement in acquired immunodeficiency syndrome (AIDS)

    International Nuclear Information System (INIS)

    Involvement of the central nervous system in acquired immune deficiency syndrome (AIDS) is usually due to opportunistic infections; these frequently offer a difficult differential diagnostic problem. Imaging methods play an important part in the elucidation of symptoms. CT and MR findings were analysed in 13 patients with AIDS and neurological symptoms. Some infections of the central nervous system (encephalitis of unknown aetiology, cytomegalic encephalitis, meningitis) may show cerebral atrophy or even no morphological changes. Toxoplasmosis and PML are the most common opportunistic infections typical changes on CT and MR may lead to diagnosis. MR offers advantages compared with CT in its higher sensitivity for the demonstration even of small lesions. (orig.)

  20. The therapeutic effect of small dose of estrogen on cerebral infarction%小剂量雌激素对缺血性脑卒中的治疗作用

    Institute of Scientific and Technical Information of China (English)

    王明刚; 李春盛; 高春锦; 王硕; 段春苗

    2008-01-01

    目的 探讨雌激素对缺血性脑卒中的神经保护机制.方法 选择40例经临床与影像学检查证实为大脑中动脉梗死的男性患者作为研究对象.按随机原则分为激素治疗组和常规治疗对照组,两组综合治疗相同;激素组加用己烯雌酚2 mg,每日2次.于治疗前及治疗后3、7、14和21 d取血测定雌二醇(E2)、睾酮(Ts)、总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、白细胞介素-1β(IL-1β)、一氧化氮(NO),并对患者进行美国国立卫生院神经功能缺损评分(NIHSS)评定.结果 与治疗前比较,激素组治疗后3 d起HDL-C、E:均明显升高,TC、LDL-C均明显降低,且较常规组变化明显,差异均有统计学意义(P均<0.05);而TG、Ts变化不明显.常规组治疗后14 d起N0、IL-1β明显升高(P均<0.05);而激素组自治疗后3 d起NO、IL-1β均较常规组显著降低,NIHSS于治疗后14 d和21 d明显降低(P均<0.05).结论 小剂量雌激素对急性缺血性脑卒中具有保护作用,其作用机制可能是通过调节血脂、抗免疫性炎症、调节NO合成等发挥作用.小剂量、短时程使用雌激素对急性缺血性脑卒中患者可能是有益的.%Objective To investigate the mechanism of protective effect of estrogen on cerebral damage in ischemic stroke by measuring the estrogen2 (E2),blood lipid,interleukin-1β (IL-1β),nitric oxide (NO),and also assessment according to national institute of health stroke scale (NIHSS) score,in order to improve the treatment of cerebral infarction.Methods Forty male patients,in whom cerebral infarction due to thrombosis of middle cerebral artery was confirmed by CT or magnetic resonance imaging (MRI),were divided into two groups : E2 therapy (20 cases) and routine therapy (20 cases).Routine therapy was the same in both groups,except 2 mg of Ez was orally given (2 times a day) to the E2 therapy group.E2,testosterone (Ts),total cholesterol

  1. Reactor vessel stud thread protector

    International Nuclear Information System (INIS)

    This patent describes a stud thread protector for a nuclear reactor pressure vessel. The vessel has a removable closure head, the closure head being sealingly engaged with the pressure vessel by a plurality of stud bolts, an upper end thereof having a threaded section for threadingly engaging a nut and a vertical bore being disposed within the stud bolt. The stud thread protector encloses the exposed upper portion of the bolt and associated nut projecting above the closure head. The reactor vessel stud thread protector is comprised of: a tubular wall portion being opened at its lower end and substantially closed at its upper end; a drip pan associated with the outer surface of the protector, the drip pan being disposed radially inwardly with respect to the outer periphery of the vessel head, whereby the drip pan collects any fluid being emitted from the reactor vessel; and means for fastening the stud thread protector to an associated stud

  2. Study on vessels' seismic buckling

    International Nuclear Information System (INIS)

    Inspection on Kashiwazaki-Kariwa Nuclear Power Station after the Niigateken Chuetsu-oki Earthquake in 2007 observed obvious buckling in some fluid storage vessels, the filtrate tanks and de-ionized Water tanks. All vessels with buckling belong to Seismic class C. Contrary the other vessels such as Diesel tanks showed no damage. Those phenomena presumably are brought about by differences in the vessels' condition (Vessels geometries, Fluid weight, etc.) and the seismic load on each vessel. In this study, the elephant's foot buckling occurred on the filtrate tank was simulated by FEM analysis of the large displacement elastic-plastic model with the recorded time history of seismic acceleration. The same analysis on the diesel was conducted tank to see that no damage took place also in the analysis. (author)

  3. Viscoelastic evaluation of fetal umbilical vein for reconstruction of middle cerebral artery

    Institute of Scientific and Technical Information of China (English)

    Dongyuan Li; Donghui Xu; Peng Li; Jun Wei; Kun Yang; Conghai Zhao

    2013-01-01

    The transplantation of artificial blood vessels with<6 mm inner diameter as substitutes for human arterioles or veins has not achieved satisfactory results. Umbilical vein has been substituted for ar-tery in vascular transplantation, but it remains unclear whether the stress relaxation and creep tween these vessels are consistent. In this study, we used the fetal umbilical vein and middle cere-bral artery from adult male cadavers to make specimens 15 mm in length, 0.196-0.268 mm in nica media thickness, and 2.82-2.96 mm in outer diameter. The results demonstrated that the stress decrease at 7 200 seconds was similar between the middle cerebral artery and fetal umbilical vein specimens, regardless of initial stress of 18.7 kPa or 22.5 kPa. However, the strain increase at 7 200 seconds of fetal umbilical veins was larger than that of middle cerebral arteries. Moreover, the stress relaxation experiment showed that the stress decrease at 7 200 seconds of the fetal umbilical vein and middle cerebral artery specimens under 22.5 kPa initial stress was less than the decrease in these specimens under 18.7 kPa initial stress. These results indicate that the fetal umbilical vein has appropriate stress relaxation and creep properties for transplantation. These properties are advantageous for vascular reconstruction, indicating that the fetal umbilical vein can be transplanted to repair middle cerebral artery injury.

  4. Cerebral imaging in pediatrics

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, I. [London, Great Ormond Street Hospital for Children (United Kingdom)

    1998-06-01

    Radioisotope brain imaging has focused mainly on regional cerebral blood flow (rCBF). However the use of ligand which go to specific receptor sites is being introduced in pediatrics, mainly psychiatry. rCBF is potentially available in many institutions, especially with the availability of multi-headed gamma cameras. The use of this technique in pediatrics requires special attention to detail in the manner of data acquisition and handling the child. The interpretation of the rCBF study in a child requires knowledge of normal brain maturation. The major clinical use in pediatrics is epilepsy because of the advances in surgery and the frequency of complex partial seizures. Other indications in pediatric neurology include brain death, acute neurological loss including stroke, language disorders, cerebral palsy, hypertension due to renovascular disease, traumatic brain injury and migraine. There are pediatric physiological conditions in which rCBF has been undertaken, these include anorexia nervosa, autism, Gilles de la Tourette syndrome (GTS) and attention deficit disorder-hyperactivity (ADHD). Research using different ligands to specific receptor sites will also be reviewed in pediatrics.

  5. Cerebral imaging in pediatrics

    International Nuclear Information System (INIS)

    Radioisotope brain imaging has focused mainly on regional cerebral blood flow (rCBF). However the use of ligand which go to specific receptor sites is being introduced in pediatrics, mainly psychiatry. rCBF is potentially available in many institutions, especially with the availability of multi-headed gamma cameras. The use of this technique in pediatrics requires special attention to detail in the manner of data acquisition and handling the child. The interpretation of the rCBF study in a child requires knowledge of normal brain maturation. The major clinical use in pediatrics is epilepsy because of the advances in surgery and the frequency of complex partial seizures. Other indications in pediatric neurology include brain death, acute neurological loss including stroke, language disorders, cerebral palsy, hypertension due to renovascular disease, traumatic brain injury and migraine. There are pediatric physiological conditions in which rCBF has been undertaken, these include anorexia nervosa, autism, Gilles de la Tourette syndrome (GTS) and attention deficit disorder-hyperactivity (ADHD). Research using different ligands to specific receptor sites will also be reviewed in pediatrics

  6. Cerebral sinus venous thrombosis.

    Science.gov (United States)

    Alvis-Miranda, Hernando Raphael; Milena Castellar-Leones, Sandra; Alcala-Cerra, Gabriel; Rafael Moscote-Salazar, Luis

    2013-10-01

    Cerebral sinus venous thrombosis (CSVT) is a rare phenomenon that can be seen with some frequency in young patients. CSVT is a multifactorial condition with gender-related specific causes, with a wide clinical presentation, the leading causes differ between developed and developing countries, converting CSVT in a condition characterized by a highly variable clinical spectra, difficult diagnosis, variable etiologies and prognosis that requires fine medical skills and a high suspicious index. Patients who presents with CSVT should underwent to CT-scan venography (CVT) and to the proper inquiry of the generating cause. This disease can affect the cerebral venous drainage and related anatomical structure. The symptoms may appear in relation to increased intracranial pressure imitating a pseudotumorcerebri. Prognosis depends on the early detection. Correcting the cause, generally the complications can be prevented. Mortality trends have diminished, and with the new technologies, surely it will continue. This work aims to review current knowledge about CSVT including its pathogenesis, etiology, clinical manifestations, diagnosis, and treatment. PMID:24347950

  7. Cerebral sinus venous thrombosis

    Directory of Open Access Journals (Sweden)

    Hernando Raphael Alvis-Miranda

    2013-01-01

    Full Text Available Cerebral sinus venous thrombosis (CSVT is a rare phenomenon that can be seen with some frequency in young patients. CSVT is a multifactorial condition with gender-related specific causes, with a wide clinical presentation, the leading causes differ between developed and developing countries, converting CSVT in a condition characterized by a highly variable clinical spectra, difficult diagnosis, variable etiologies and prognosis that requires fine medical skills and a high suspicious index. Patients who presents with CSVT should underwent to CT-scan venography (CVT and to the proper inquiry of the generating cause. This disease can affect the cerebral venous drainage and related anatomical structure. The symptoms may appear in relation to increased intracranial pressure imitating a pseudotumorcerebri. Prognosis depends on the early detection. Correcting the cause, generally the complications can be prevented. Mortality trends have diminished, and with the new technologies, surely it will continue. This work aims to review current knowledge about CSVT including its pathogenesis, etiology, clinical manifestations, diagnosis, and treatment.

  8. Inflammatory demyelinating pseudotumor with hemorrhage masquerading high grade cerebral neoplasm

    Directory of Open Access Journals (Sweden)

    Amit Agrawal

    2015-03-01

    Full Text Available Demyelinating pseudotumors are rare, benign, solitary intracranial space occupying lesions which masquerade cerebral neoplasms. Contrast MRI shows open ring enhancement which is fairly specific for this entity. Advanced MRI techniques like MR spectroscopy and magnetizing transfer techniques can help differentiating these lesions. NAA/Cr ratio is significantly elevated in central regions of demyelinating pseudotumors than in gliomas and other lesions. Presence of abundant foamy macrophages, lymphoid inflammatory infiltrates around blood vessels, sheets of gemistocytic astrocytes with well-developed processes, well defined border of the lesion absence of neovascularity and necrosis should help us diagnose demyelinating pseudotumor fairly confidently on histopathology.

  9. The vessel fluence; Fluence cuve

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This book presents the proceedings of the technical meeting on the reactors vessels fluence. They are grouped in eight sessions: the industrial context and the stakes of the vessels control; the organization and the methodology for the fluence computation; the concerned physical properties; the reference computation methods; the fluence monitoring in an industrial context; vessels monitoring under irradiation; others methods in the world; the research and development programs. (A.L.B.)

  10. Blood vessel rupture by cavitation

    OpenAIRE

    Chen, Hong; Brayman, Andrew A.; Bailey, Michael R.; Matula, Thomas J.

    2010-01-01

    Cavitation is thought to be one mechanism for vessel rupture during shock wave lithotripsy treatment. However, just how cavitation induces vessel rupture remains unknown. In this work, a high-speed photomicrography system was set up to directly observe the dynamics of bubbles inside blood vessels in ex vivo rat mesenteries. Vascular rupture correlating to observed bubble dynamics were examined by imaging bubble extravasation and dye leakage. The high-speed images show that bubble expansion ca...

  11. Reactor pressure vessel cooling device

    International Nuclear Information System (INIS)

    A spray pipeline for the head of a pressure vessel is connected to a spray for the pressure vessel head of the reactor pressure vessel. The pipeline is equipped with a spray flow rate control valve for controlling the flow rate of spray jetted from the head spray to the inside of the reactor and a thermometer for spray water. A reactor pressure vessel cooling and controlling portion intakes temperature signals sent from a thermometer for the head of the pressure vessel, a thermometer for the flange of the pressure vessel and a thermometer for the body of the pressure vessel, and a thermometer for spray water. Then, it outputs restriction signal for the opening degree of the spray flow rate control valve to restrict the spray water flow rate within an appropriate range when the difference between the temperature of each portion of the pressure vessel and the temperature of spray water is increased to greater than an allowable temperature difference. With such procedures, spray operation for the head of the pressure vessel can be conducted not only upon emergency but also during reactor cooling operation. (I.N.)

  12. Americium behaviour in plastic vessels

    Energy Technology Data Exchange (ETDEWEB)

    Legarda, F.; Herranz, M. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R., E-mail: raquel.idoeta@ehu.e [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Abelairas, A. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain)

    2010-07-15

    The adsorption of {sup 241}Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of {sup 241}Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of {sup 241}Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  13. Americium behaviour in plastic vessels

    International Nuclear Information System (INIS)

    The adsorption of 241Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of 241Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of 241Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  14. Carotid angioplasty with cerebral protection

    International Nuclear Information System (INIS)

    Background. Carotid endarterectomy (CEA) is widely used in the management of high-grade carotid stenosis. It is a surgical procedure requiring general anaesthesia and is suitable only for lesions located at or close to the carotid bifurcation. It may develop complications, such as stroke, death, cranial nerve palsies, wound haematoma and cardiac complications. The risk of complications is increased in patients with recurrent carotid artery stenosis following CEA, in subjects undergoing radiotherapy to the neck, and in patients with cardiopulmonary disease. The drawbacks of CEA have led physicians to search for alternative treatment options. Carotid angioplasty and stenting (CAS) is less invasive than CEA. The method is particularly suitable for the treatment of recurrent stenosis after previous CEA and distal internal artery stenosis, which is inaccessible for CEA. CAS does not cause cranial nerve palsies. Moreover, it does not require general anaesthesia and causes lower morbidity and mortality in patients with severe cardiopulmonary disease. The complications of CAS include stroke due to distal immobilisation of a plaque or thrombus dislodged during the procedure, abrupt vessel occlusion due to thrombosis, dissection or vasospasm, and restenosis due to intimal hyperplasia. CAS is a relatively new procedure; therefore, it is essential to establish its efficacy and safety before it is introduced widely into clinical practice. Patients and methods. In Slovenia, we have also started with carotid angioplasty by the study: Slovenian Carotid Angioplasty Study (SCAS). We performed CAS in 17 patients (12 males and 5 females) aged from 69 to 82 years. All patients were symptomatic with stenosis greater than 70 %. 10 patients suffered transient ischemic attacks, 4 patients minor strokes and 3 patients amaurosis fugax. Results. Technical success (< 30 % residual stenosis) was achieved in all cases. In 14 patients, no residual stenosis was found, in 2 patients a 15 % residual

  15. Obstructive hydrocephalus resulting from cerebral venous thrombosis

    OpenAIRE

    2011-01-01

    Cerebral venous thrombosis is a rare form of stroke in childhood. Increased intracranial pressure is a well-defined complication of cerebral venous thrombosis but obstructive hydrocephalus as a presentation finding of cerebral venous thrombosis is rarely described. A child case of cerebral sinus thrombosis presenting with obstructive hydrocephalus and management of clinical condition is presented with discussion of reported cases and treatment recommendations.

  16. Corkscrew angiopathy of intracranial vessels in a young stroke patient: a case report

    Directory of Open Access Journals (Sweden)

    Alurkar Anand

    2012-10-01

    Full Text Available Abstract Introduction We present a rare finding of a ‘corkscrew appearance’ of the distal cerebral vessels in a young Asian woman who presented with acute stroke. Case presentation A 32-year-old Asian woman presented with a 3-month history of recurrent right-sided transient ischemic attacks. Her clinical workup and brain imaging results were normal. A digital subtraction angiogram revealed an abnormal corkscrew appearance of all intracranial distal vessels. She was discharged on a single antiplatelet drug. She had no further transient ischemic attacks on clinical follow-up. A digital subtraction angiogram performed 1 year later revealed no changes in the appearance of these vessels. Conclusion To the best of our knowledge no similar previous reports exist in the literature. The present report describes a unique case of an unusual corkscrew appearance of the distal intracranial vessels. However, the underlying etiology in the present case remains unknown.

  17. Perfusion Pressure Cerebral Infarct (PPCI) trial - the importance of mean arterial pressure during cardiopulmonary bypass to prevent cerebral complications after cardiac surgery

    DEFF Research Database (Denmark)

    Vedel, Anne G; Holmgaard, Frederik; Rasmussen, Lars Simon;

    2016-01-01

    coronary vessel and/or valve disease and who are undergoing cardiac surgery with the use of cardiopulmonary bypass. Patients are stratified by age and surgical procedure and are randomised 1:1 to either an increased mean arterial pressure (70-80 mmHg) or 'usual practice' (40-50 mmHg) during cardiopulmonary...... caused by emboli, but inadequate blood flow caused by other mechanisms may increase ischaemia in the penumbra or cause watershed infarcts. During cardiopulmonary bypass, blood pressure can be below the lower limit of cerebral autoregulation. Although much debated, the constant blood flow provided by the...... cardiopulmonary bypass system is still considered by many as appropriate to avoid cerebral ischaemia despite the low blood pressure. METHODS/DESIGN: The Perfusion Pressure Cerebral Infarct trial is a single-centre superiority trial with a blinded outcome assessment. The trial is randomising 210 patients with...

  18. Cerebral haemodynamic and metabolic changes in carotid artery occlusion: a PET study

    International Nuclear Information System (INIS)

    Using the positron emission tomography, with the O15 inhalation technique, the cerebral blood flow (CBF), the oxygen extraction fraction (OEF) and the cerebral metabolic rate of oxygen (CMRO2) were studied in 37 patients with internal carotid artery (ICA) occlusion. In the territory of the occluded ICA, two pattern of focal anomaly have been observed: a CBF decrease with a ''compensatory'' OEF increase or a matched CBF and CMRO2 decrease. On the other hand, as compared to age matched control values, CMRO2 is significantly decreased in the territory of the occluded carotid only in patients with extensive neck vessels obstructive disease

  19. Posttherapeutic cerebral radionecrosis: a complication of head and neck tumor therapy

    International Nuclear Information System (INIS)

    Patients with treated head and neck cancer may have focal neurologic symptoms and personality changes due to delayed cerebral radionecrosis. A history of past treatment should direct the physician to consider these lesions in the differential diagnosis. Craniotomy is the management recommended. Histopathologic changes include fibrotic response of the meninges with pleomorphic and vacuolated fibroblasts, capillary hyperplasia, reactive astrocytes, and fibrosis of the blood vessels. Amyloid is deposited in the arteriolar walls and extracellular space. Ischemic, autoimmune, or vascular mechanisms, and glial alterations have all been considered in the pathogensis of delayed cerebral radionecrosis. Some researchers have concluded that chemotherapeutic agents, such as methotrexate, may contribute to its production

  20. Posttherapeutic cerebral radionecrosis: a complication of head and neck tumor therapy

    Energy Technology Data Exchange (ETDEWEB)

    Araoz, C.; Weems, A.M.

    1981-12-01

    Patients with treated head and neck cancer may have focal neurologic symptoms and personality changes due to delayed cerebral radionecrosis. A history of past treatment should direct the physician to consider these lesions in the differential diagnosis. Craniotomy is the management recommended. Histopathologic changes include fibrotic response of the meninges with pleomorphic and vacuolated fibroblasts, capillary hyperplasia, reactive astrocytes, and fibrosis of the blood vessels. Amyloid is deposited in the arteriolar walls and extracellular space. Ischemic, autoimmune, or vascular mechanisms, and glial alterations have all been considered in the pathogensis of delayed cerebral radionecrosis. Some researchers have concluded that chemotherapeutic agents, such as methotrexate, may contribute to its production.