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1.
Japanese Journal of Complementary and Alternative Medicine ; : 75-83, 2011.
Artigo em Inglês | WPRIM | ID: wpr-376526

RESUMO

<b>Objective:</b> The soybean has long been an important protein source for approximately 5000 years in Oriental countries. Therefore, soy protein has been widely investigated for its variety of function. However, the side effects had been reported for its close structure of the female hormone, estrogen. In this report, we prepare a new soy peptide derivative and focus on the potency, with special attention to the linkage of peripheral leukocytes in number, emotional hormone and brain blood flow.<br> <b>Method:</b> Dried powder of soybean-protein or peptide were administered orally at dosage 8g (dry weight) suspension, the blood sample was collected before and after one week at the same hour and served for assessment in order to avoid circadian rhythm.<br> <b>Results:</b> The cell numbers were up-regulated in the group that had a smaller number of leukocytes before the test, but in the larger number group before the test, they were down-regulated in the soybean-protein and peptide. Therefore, when the number of all subjects were totaled and make mean, indicating no difference. As for the leukocyte subsets, lymphocyte numbers of CD<sub>11b</sub><sup>+</sup> cells, and CD<sub>56</sub><sup>+</sup> cells significantly increased after ingestion of a single gradient in the soybean-peptide group. On the contrary, only CD<sub>19</sub><sup>+</sup> cell counts were down regulated. In the soybean-peptide group, the adrenalin level in serum, which is regarded as one of the emotional hormones, was down regulated, and another emotional hormone, dopamine, was up regulated. There were no change of CD positive cells and emotional hormones in the soy protein and placebo group. In NIRS, a significant increase in amplitude of all the frequency bands was observed in the peptide group just after 5 min of administration by the sample, peptide.<br> <b>Conclusion:</b> These results indicate that the soybean peptides can regulate the leukocyte subsets and emotional hormones are also closely related with the change of the brain blood flow in healthy young volunteers.<br>

2.
Journal of Kunming Medical University ; (12)2006.
Artigo em Chinês | WPRIM | ID: wpr-529739

RESUMO

Objective To study the protective effects of Tianma xingnao capsule on brain blood circulation in mice and rats.Methods The arteria carotis externa was ligated,and arteria carotis interna was kept.The left carotid artery was exposed and placed over an ultrasonic flow probe.The brain flow volume was recorded with an Ultrasonic Volume.The pursiness time of mice was observed to evaluate the effect of Tianma xingnao capsule on cerebral ischemia and anoxia.The permeability of normal blood-cerebral barrier was investigated in mice.Results Tianma xingnao capsule significantly increased brain blood flow and prolonged mouse pursiness time.Tianma xingnao capsule at a dose of 4 g/kg significantly elevated the content of Evans in mouse brain.Conclusions Tianma xingnao capsule can increase the brain blood flow in rats and improve brain blood circulation in mice.It is obviously advantageous to protect against cerebral ischemia and hypoxia.

3.
Korean Journal of Radiology ; : 64-74, 2005.
Artigo em Inglês | WPRIM | ID: wpr-92861

RESUMO

One of the main reasons for the soaring interest in acute ischemic stroke among radiologists is the advent of new magnetic resonance techniques such as diffusion-weighted imaging. This new modality has prompted us to seek a better understanding of the pathophysiologic mechanisms of cerebral ischemia/infarction. The ischemic penumbra is an important concept and tissue region because this is the target of various recanalization treatments during the acute phase of stroke. In this context, it is high time for a thorough review of the concept, especially from the imaging point of view.


Assuntos
Humanos , Encéfalo/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X
4.
Korean Journal of Radiology ; : 143-148, 2004.
Artigo em Inglês | WPRIM | ID: wpr-68899

RESUMO

OBJECTIVE: The aim of this study was to examine the feasibility of perfusion imaging of the brain using the Z-score and subtraction dynamic images obtained from susceptibility contrast MR images. MATERIALS AND METHODS: Five patients, each with a normal MRI, Moya-moya, a middle cerebral artery occlusion, post-trauma syndrome, and a metastatic brain tumor, were selected for a presentation. A susceptibility-contrast echo-planar image after a routine MRI was taken as the source image with a rapid manual injection of 0.1 mmol/kg of Gd-DTPA. The inflow and washout patterns were observed from the time-signal intensity curve of the serial scans using the standard program of an MRI machine. The repeated Z-score images of the peak and late phases were made using the threshold Z-score values between 1.4 and 2.0 in four to five studies of the pre-contrast, peak, and late phases. Dynamic subtraction images were produced by subtracting sequential post-contrast images from a pre-contrast image and coloring these images using a pseudocolor mapping method. RESULTS: In the diseases with perfusion abnormalities, the Z-score images revealed information about the degree of perfusion during the peak and late phases. However, the quality varied with the Z-score threshold and the studies selected in a group. The dynamic subtraction images were of sufficient quality with no background noise and more clearly illustrated the temporal changes in perfusion and delayed perfusion. CONCLUSION: The Z-scores and dynamic subtraction images illustrated the degree of perfusion and sequential changes in the pattern of perfusion, respectively. These images can be used as a new complimentary method for observing the perfusion patterns in brain diseases.


Assuntos
Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Encéfalo/irrigação sanguínea , Meios de Contraste , Estudos de Viabilidade , Gadolínio DTPA , Angiografia por Ressonância Magnética , Técnica de Subtração
5.
Journal of the Korean Society of Magnetic Resonance in Medicine ; : 124-131, 2003.
Artigo em Coreano | WPRIM | ID: wpr-160673

RESUMO

PURPOSE: To reveal clinical usefulness of functional MRI (fMRI) using sensorymotor and language stimuli for demonstrating anatomic relationship between sensorimotor or language cortices and lesions in the planning of brain tumor surgery. MATERIALS AND METHODS: This study included 12 right-handed patients with brain tumors in or around sensorimotor or language cortices. Eleven patients were evaluated with primary motor and sensory stimuli. Of these patients, six patients were also evaluated with language stimuli. One patient was evaluated with language stimuli only. For fMR imaging, a 1.5T scanner was used and the EPI BOLD technique was employed. For postprocessing image, the SPM99 program and a program made by our department was utilized. We evaluated whether sensorimotor and language stimuli activate sensorimotor and language cortices. And also, clinical efficacy of revealing anatomic relationship between cerebral cortices and lesions for planning neurosurgical operation were evaluated. Finally, we compared post-operative neurologic function with pre-operative neurologic function in same patients. RESULTS: The fMRI examination was successful in identifying the functional cortices and depicting anatomic relationship between functional cortices and lesions in all patients. In nine patients of 11 patients with identified sensorimotor cortices, postoperative grade of manual motor test was not changed, compared with preoperative grade. Whereas postoperative improved than preoperative grade in one patient of remaining two patients, postoperative aggravated than preoperative grade in the other. This result was due to atherosclerotic lacunar infarction, regardless of tumor resection. Postoperative deficit of language function was not found in seven patients with identified language cortices. CONCLUSION: fMRI could be a helpful method for determining the best approach to neurosurgical treatment in patients with brain tumors in or around sensorimotor or language cortices.


Assuntos
Humanos , Neoplasias Encefálicas , Encéfalo , Córtex Cerebral , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral Lacunar
6.
Journal of the Korean Society of Magnetic Resonance in Medicine ; : 55-63, 2002.
Artigo em Coreano | WPRIM | ID: wpr-169381

RESUMO

PURPOSE: We investigated the predictive values of relative CBV measured with perfusion MR imaging, and relative CBF measured with SPECT for tissue outcome in acute ischemic stroke. MATERIALS AND METHODS: Thirteen patients, who had acute unilateral middle cerebral artery occlusion, underwent perfusion MR imaging, and 99mTc-HMPAO SPECT within 6 hours after the onset of symptoms. Lesion-to-contralateral ratios of perfusion parameters were measured, and best cut-off values of both parameter ratios with their accuracy to discriminate between regions with and without evolving infarction were calculated. RESULTS: Mean relative CBV ratios in regions with evolving infarction and without evolving infarction were 0.58+/-0.27 and 0.99+/-0.17 (p 0.05 between two parameters). CONCLUSION: Measurement of relative CBV and relative CBF may be useful in predicting tissue outcome in acute ischemic stroke.


Assuntos
Humanos , Infarto , Infarto da Artéria Cerebral Média , Imageamento por Ressonância Magnética , Perfusão , Sensibilidade e Especificidade , Acidente Vascular Cerebral , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada de Emissão de Fóton Único
7.
Journal of the Korean Radiological Society ; : 417-423, 2002.
Artigo em Coreano | WPRIM | ID: wpr-112142

RESUMO

PURPOSE: To determine the usefulness of the functional MRI (fMRI) using motor and sensory stimuli in patients with brain tumors or focal cerebral lesions. MATERIALS AND METHODS: This study involved five patients with brain tumors (n=2) or cerebral lesions [cysticercosis (n=1), arteriovenous malformation (n=1), focal infarction (n=1)] and seven normal controls. For MR examinations a 1.5T scanner was used, and during motor or sensory stimulation, the EPI BOLD technique was employed. For image postprocessing an SPM program was utilized. RESULTS: In volunteers, contralateral sensori-motor cortices were activated by both motor and sensory stimuli, while supplementary motor cortices were activated by motor stimuli and other sensory cortices by sensory stimuli. Preoperative evaluation of the relationship between lesions and important sensory and motor areas was possible, and subsequent surgery was thus successful, involving no severe complications. Activation of ipsilateral or other areas occurred in patients with destruction of a major sensory and/or motor area, suggesting compensatory reorganization. CONCLUSION: fMRI could be a useful supportive method for determining the best approach to surgery treatment in patients with brain tumors or focal cerebral lesions.


Assuntos
Humanos , Malformações Arteriovenosas , Neoplasias Encefálicas , Encéfalo , Infarto , Imageamento por Ressonância Magnética , Voluntários
8.
Journal of the Korean Radiological Society ; : 425-430, 2002.
Artigo em Coreano | WPRIM | ID: wpr-112141

RESUMO

PURPOSE: To compare functional MR imaging of the motor cortex during active and passive movement. MATERIALS AND METHODS: Seven healthy, right-handed volunteers (M:F=6:1; age:25-30 years) were included in this study. A 1.5-T whole body scanner and the multislice EPI BOLD method were used. The motor paradigm was flexion-extension of a thumb against rest. In the active motion task, the thumb was flexed voluntarily once a second, while in the passive task, it was tied with a thread and pulled to flex and extend passively at the same interval and with the same intensity as in the active task. For image postprocessing, an SPM 96 program was used. The sites, numbers, and signal intensity of the activated pixels were determined, and the threshold for significance was set at p<0.001 to p<0.01. RESULTS: In the active motion task, strong activation at the contralateral side of the primary sensorimotor cortex and supplementary motor cortex occurred in all 14 examples in all seven volunteers. Additionally, the ipsilateral primary sensorimotor cortex and supplementary motor area were activated in 12/14 and 11/14 such tasks, respectively. During passive motion tasks, on the other hand, weak activation occurred at the contralateral side of the primary sensorimotor cortex in all cases, but in the contralateral supplementary motor cortex in only three. In the ipsilateral primary sensorimotor cortex and supplementary motor area, there was no activation. CONCLUSION: Compared with the active motion task, activation occurring in the contralateral primary sensorimotor cortex and supplementary cortex was weaker and less frequent during the passive task, and during this latter, the ipsilateral motor cortex remained inactive. These results may be useful for the clinical application of functional MR imaging in unconscious patients or in animal studies.


Assuntos
Animais , Humanos , Mãos , Imageamento por Ressonância Magnética , Córtex Motor , Polegar , Voluntários
9.
Journal of the Korean Radiological Society ; : 343-350, 2002.
Artigo em Coreano | WPRIM | ID: wpr-38842

RESUMO

PURPOSE: To evaluate the clinical outcome and other relevant factors in cases where local intra-aterial thrombolysis (LIT) is used for the threatment of hyperacute ischemic stroke. MATERIALS AND METHODS: Forty-eight hyperacute ischemic stroke patients were treated by LIT, using urokinase, within six hours of ictus, and for evaluation of their neurological status, the National Institutes of Health Stroke Scale (NIHSS) score was used. Angiographic recanalization was classified according to Mori recanalization grades. Three months after LIT, the outcome was assessed by clinical examination using the modified Rankin scale (good outcome: RS=0-3; poor outcome: RS=4-6). In all patients, the findings of pre- and post- LIT CT, and angiography, as well as neurological status and hemorrhagic complications, were also analysed. RESULTS: Thirty-three patients had occlusions of the middle cerebral artery (MCA), and 15, of the internal carotid artery (ICA). The NIHSS score averaged 16.9 at the onset of therapy and 13.5 at 24 hours later. Successful recanalization (Mori grade 3,4) was achieved in 28 (58.3%) of 48 patients, but in 20 (41.7%) the attempt failed. Twenty-two (45.8%) of the 48 patients had a good outcome, but in (54.2%) the outcome was poor. Thirteen (40.6%) of 32 patients with MCA occlusions and 13 (81.2%) of 16 with ICA occlusions had a poor outcome. Eight patients (16.7%) died. Overall, hemorrhages occured in 20 (41.7%) of 48 patients, with symptomatic hemorrhage in ten. Five (50%) of these ten died. CONCLUSION: LIT using urokinase for hyperacute ischemic stroke is feasible; patients with MCA occlusions had better outcomes than those with ICA occlusions. Hemorrhagic complications of LIT were frequent, and in cases of symptomatic hemorrhage a fatal outcome may be expected.


Assuntos
Humanos , Angiografia , Artéria Carótida Interna , Evolução Fatal , Hemorragia , Artéria Cerebral Média , Acidente Vascular Cerebral , Ativador de Plasminogênio Tipo Uroquinase
10.
Journal of the Korean Radiological Society ; : 431-436, 2002.
Artigo em Coreano | WPRIM | ID: wpr-36874

RESUMO

PURPOSE: To correlate the findings of perfusion-weighted imaging (PWI) with clinical outcomes in patients with acute lacunar infarction. MATERIALS AND METHODS: Eleven patients (7 males and 4 females) with acute lacunar infarction who were examined within 50 (mean, 29) hours of the onset of symptoms underwent conventional MRI, diffusion-weighted imaging (DWI) and PWI. Gadolinium (0.2 mmol/kg) was injected at a rate of 2 ml/sec, and PWI was performed using a gradient-echo EPI pulse sequence and the following parameters: TR/TE, 2000/60; flip angle, 90 degree; matrix size, 128X128. Relative cerebral blood volume (rCBV) maps were derived from gadolinium bolus perfusion-weighted images where rCBV ratios between infarcted areas were detected by DWI, and contralateral control areas were obtained. In each case, the resulting rCBV ratio at a lesion site was compared with the clinical outcome determined on the basis of the difference between National Institute Health Stroke Scale (NIHSS) scores at admission and discharge. RESULTS: With the aid of the time-intensity curve obtained at PWI, the rCBV maps revealed a hypoperfused area in 10 of 11 patients, and there was positive correlation (r=0.81) with clinical outcome. CONCLUSION: Although PWI has a lower detection rate than DWI, it may be a useful modality for helping determine prognosis in cases of acute lacunar infarction.


Assuntos
Humanos , Masculino , Volume Sanguíneo , Diagnóstico , Gadolínio , Imageamento por Ressonância Magnética , Perfusão , Prognóstico , Acidente Vascular Cerebral , Acidente Vascular Cerebral Lacunar
11.
Journal of Practical Radiology ; (12)2001.
Artigo em Chinês | WPRIM | ID: wpr-541628

RESUMO

Objective To evaluate the value of dynamic susceptibility-contrast (DSC) MR perfusion imaging in differentiating benign and malignant meningiomas on the basis of differences in their vascularity in both tumor parenchyma and peritumoral region. Methods 33 patients with pre-operation meningiomas(25 benign and 8 malignant) underwent conventional and DSC MR perfusion imaging. Maximum relative cerebral blood volume (rCBV) and corresponding relative mean transit time (rMTT) values of the same part in both tumor parenchyma and peritumoral region were calculated (compared with contralateral normal white matter). The peritumoral region was defined as the area immediately adjacent (0.05) in parenchyma part and both were statistically significant (t test, ?

12.
Korean Journal of Radiology ; : 1-7, 2001.
Artigo em Inglês | WPRIM | ID: wpr-171865

RESUMO

OBJECTIVE: To determine the usefulness of perfusion MR imaging in assessing the histologic grade of cerebral gliomas. MATERIALS AND METHODS: In order to determine relative cerebral blood volume (rCBV), 22 patients with pathologically proven gliomas (9 glioblastomas, 9 anaplastic gliomas and 4 low-grade gliomas) underwent dynamic contrast-enhanced T2*-weighted and conventional T1- and T2-weighted imaging. rCBV maps were obtained by fitting a gamma-variate function to the contrast material concentration versus time curve. rCBV ratios between tumor and normal white matter (maximum rCBV of tumor / rCBV of contralateral white matter) were calcu-lated and compared between glioblastomas, anaplastic gliomas and low-grade gliomas. RESULTS: Mean rCBV ratios were 4.90'+/-1.01 for glioblastomas, 3.97'+/-0.56 for anaplastic gliomas and 1.75'+/-1.51 for low-grade gliomas, and were thus sig-nificantly different; p < .05 between glioblastomas and anaplastic gliomas, p <.05 between anaplastic gliomas and low-grade gliomas, p < .01 between glioblas-tomas and low-grade gliomas. The rCBV ratio cutoff value which permitted dis-crimination between high-grade (glioblastomas and anaplastic gliomas) and low-grade gliomas was 2.60, and the sensitivity and specificity of this value were 100% and 75%, respectively. CONCLUSION: Perfusion MR imaging is a useful and reliable technique for esti-mating the histologic grade of gliomas.


Assuntos
Adulto , Feminino , Humanos , Masculino , Astrocitoma/patologia , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Circulação Cerebrovascular , Meios de Contraste , Gadolínio DTPA , Glioblastoma/patologia , Imageamento por Ressonância Magnética
13.
Journal of the Korean Radiological Society ; : 575-580, 2001.
Artigo em Coreano | WPRIM | ID: wpr-197725

RESUMO

PURPOSE: To compare of quantitative measurement of the total cerebral blood flow using two-dimensional phase-contrast MR imaging and Doppler ultrasound. MATERIALS AND METHODS: In 16 volunteers (mean age, 26 years; mean body weight, 66 kg) without abnormal medical histories, two-dimensional phase-contrast MR imaging was performed at the level of the C2-3 intervertebral disc for flow measurement of the internal carotid arteries and the vertebral arteries. Volume flow measurements using Doppler ultrasound were also performed at the internal carotid arteries 2 cm above the carotid bifurcation, and at the vertebral arteries at the level of the upper pole of the thyroid gland. Flows in the four vessels measured by the two methods were compared using Wilcoxon's correlation analysis and the median score. Total cerebral blood flows were calculated by summing these four vessel flows, and mean values for the 16 volunteers were calculated. RESULTS: Cerebral blood flows measured by 2-D phase-contrast MR imaging and Doppler ultrasounds were 233 and 239 ml/min in the right internal carotid artery, 250 and 248 ml/min in the left internal carotid artery, 62 and 56 ml/min in the right vertebral artery, and 83 and 68 ml/min in the left vertebral artery. Correlation coefficients of the blood flows determined by the two methods were 0.48, 0.54, 0.49, and 0.62 in each vessel, while total cerebral blood flows were 628+/-68 (range, 517 to 779) ml/min and 612+/-79 (range, 482 to 804)ml/min, respectively. CONCLUSION: Total cerebral blood flow was easily measured using 2-D phase-contrast MR imaging and Doppler ultrasound, and the two noninvasive methods can therefore be used clinically for the measurement of total cerebral blood flow.


Assuntos
Peso Corporal , Artéria Carótida Interna , Disco Intervertebral , Imageamento por Ressonância Magnética , Glândula Tireoide , Ultrassonografia , Artéria Vertebral , Voluntários
14.
Journal of the Korean Radiological Society ; : 897-904, 2000.
Artigo em Inglês | WPRIM | ID: wpr-9889

RESUMO

Pupose:To evaluate the results of intra-arterial urokinase thrombolysis in cases of acute ischemic stroke and to define the factors affecting prognosis. MATERIALS AND METHODS:Forty-eight patients with angiographically proven occlusion of the intracranial arteries were treated with local intra-arterial infusion of urokinase within six hours of the onset of symptoms. Neurologic status was evaluated on admis-sion and on discharge using the NIH(National Institute of Health) stroke scale score (SSS). When the SSS decreased by at least four points, this was considered indicative of an improved clinical outcome. RESULTS: Complete recanalization was achieved in 17/48 patients (35%), including 8 of 13 (62%) with occlusion of the vertebrobasilar artery (VBA), 9 of 20 (45%) with occlu-sion of the middle cerebral artery (MCA), and none of 15 with occlusion of the internal carotid artery (ICA). Neurologic status improved in 12 (60%) of patients with MCA oc-clusion, in five (38%) of those with VBA occlusion and in three (20%) of those with ICA occlusion (P<0.05). Patients in whom occluded MCA was completely recanalized showed greater clinical improvement than those with partial or no recanalization (P<0.05). The overall mortality rate was 21%, 43% (9/21) in patients in whom CT revealed signs of early infarct, but only 4% (1/27) in those without this sign (P<0.05). The mortality rate of patients with parenchymal hematoma (4/5) was higher than that of those with hemorrhagic infarct (3/9) or without hemorrhage (3/34) (P<0.05). CONCLUSION: In patients in whom occluded MCA was completely recanalized, the clinical outcome was better, while patients with VBA occlusion did not benefit from re-canalization. The presence on CT scans of signs of early infarct and of parenchymal hematoma after thrombolysis correlated with a high mortality rate.


Assuntos
Humanos , Artérias , Artéria Carótida Interna , Hematoma , Hemorragia , Infusões Intra-Arteriais , Artéria Cerebral Média , Mortalidade , Prognóstico , Acidente Vascular Cerebral , Tomografia Computadorizada por Raios X , Ativador de Plasminogênio Tipo Uroquinase
15.
Journal of the Korean Radiological Society ; : 249-255, 1998.
Artigo em Coreano | WPRIM | ID: wpr-121520

RESUMO

PURPOSE: To assess regional cerebral blood volume and perfusion rate by MR imaging. MATERIALS AND METHODS:Eight normal volunteers and one patient underwent MR imaging after bolus injection of a double dose ofgadoinium(0.2mMol/kg). Gradient-echo EPI pulse sequencing was used, with TR/TE 1500/40msec, flip angle 90o, matrixsize 256X128. One hundred sequential images at the same level were obtained. The time-signal intensity curve wasplotted and converted to a time-concentration ( R2) curve. Relative cerebral blood volume was determined, withintegration of time-concentration curve pixel by pixel. Perfusion rate was determined by calculating maximal slopeof the R2 curve and the time taken to attain this. RESULTS: On volume maps, clear differentiation of gray matter,white matter and major vessels was established. The mean gray and white matter ratio of blood volume was2.78+/-0.43. Slope and volume maps were similar, but in one patient perfusion was apparently greater on the ratemap than on the volume map. CONCLUSION: Cerebral blood volvme and slope map images reflect changes in cerebralhemodynamics. It is thought that these findings can be clinically applied to the determination of vascularity inbrain tumors and acute cerebral ischemia


Assuntos
Humanos , Volume Sanguíneo , Isquemia Encefálica , Voluntários Saudáveis , Imageamento por Ressonância Magnética , Perfusão
16.
Journal of the Korean Radiological Society ; : 197-203, 1998.
Artigo em Coreano | WPRIM | ID: wpr-89382

RESUMO

PURPOSE: The purpose of this study was to evaluate the temporal pattern of blood volume change in cerebralinfarction and to provide guidelines for the interpretation of blood volume data known to vary according to thestage of infarction. MATERIALS AND METHODS: Thirteen patients with large infarctions attributable to proximalmiddle cerebral artery occlusion were studied at least twice after the onset of stroke using dynamiccontrast-enhanced T2*-weighted MR imaging and MR angiography. A total of 34 infarctions (11 in the acute stage[< or =7 days], 13 in the subacute stage [8-21 days], and 10 in the chronic stage [22-35 days]) were included. Afterblood volume maps were created on a pixel-by-pixel basis, blood volume ratios (blood volume of the infarctedregion divided by blood volume of the corresponding contralateral region) and findings of MR angiograms werecompared at different stages. RESULTS: A changing biphasic pattern of blood volume ratios was found: 0.73 in theacute stage, 1.45 in the subacute stage and 0.73 in the chronic stage (p < .01). Mean blood volume ratios ininfarctions with and without recanalization of occluded arteries were 1.37 and 0.42, respectively, a significantdifference (p <.001). Recanalization occurred during the acute stage in 45% of infarctions, and during the subacutestage in 77%. CONCLUSION: Blood volume that initially decreases in cerebral infarction increases during thesubacute stage, reflecting reperfusion hyperemia, and decreases again during the chronic stage. For correctinterpretation of blood volume data in cerebral infarction at various stages, the time interval between the onsetof stroke and MR examination and recanalization of arteries must be considered.


Assuntos
Humanos , Angiografia , Artérias , Volume Sanguíneo , Artérias Cerebrais , Infarto Cerebral , Seguimentos , Hiperemia , Infarto , Imageamento por Ressonância Magnética , Reperfusão , Acidente Vascular Cerebral
17.
Journal of the Korean Radiological Society ; : 205-210, 1998.
Artigo em Coreano | WPRIM | ID: wpr-89381

RESUMO

PURPOSE: To investigate the feasibility of functional MR imaging of motor language function and its usefulnessin the determination of hemispheric language dominance. MATERIALS AND METHODS: In order to activate the motorcenter of language, six subjects(5 right-handed, 1 left-handed; 3 males, 3 females) generated words. They wererequested to do this silently, without physical articulation, in response to English letters presented visually.Gradient-echo images (TR/TE/flip angle, 80/60/40o; 64x128 matrix; 10mm thickness) were obtained in three axialplanes including the inferior frontal gyrus. Functional maps were created by the postprocessing of gradient-echoimages, including subtraction and statistics. Areas of activation were topographically analyzed and numbers ofactivated pixels in each region were compared between right and left sides. The reproducibility of functional mapswas tested by repetition of functional imaging in the same subjects. RESULTS: Statistically significant activationsignals were demonstrated in five of six subjects, in whom the distribution of those signals was predominantly inboth frontal lobes. Hemispheric lateralization of activation, when activated pixels were compared between bothinferior frontal gyri, was in all cases on the left. In four subjects, functional maps were reproduced in asimilar fashion. CONCLUSION: Our results suggest that functional MR imaging can depict the activation of motorlanguage function in the brain and can be used as a useful non-invasive method for determining the hemisphericdominance of language.


Assuntos
Humanos , Masculino , Mapeamento Encefálico , Encéfalo , Lobo Frontal , Imageamento por Ressonância Magnética
18.
Journal of the Korean Radiological Society ; : 887-893, 1998.
Artigo em Coreano | WPRIM | ID: wpr-223702

RESUMO

PURPOSE: Perfusion MR imaging is a new technique for the assessment of acute ischemic stroke. The aim of thisstudy was to evaluate the usefulness of this imaging in hyperacute ischemic stroke in comparison with conventionalCT and MR imaging. MATERIALS AND METHODS: Eight patients presenting the symptoms of acute ischemic stroke due tomiddle cerebral artery occlusion were included in this study. Within 2 hours of initial CT scan and 6 hours afterthe onset of stroke, perfusion MR imaging was performed in all patients using a single-section dynamiccontrast-enhanced T2*-weighted imager in conjunction with conventional routine MR imaging and MR angiography.Cerebral blood volume (CBV) maps were then obtained from dynamic MR imaging data by using numerical integrationtechniques. The findings of CBV maps were compared with those of initial and follow-up CT or MR images. RESULTS: The findings of CBV maps were obviously abnormal in all patients, as compared with normal or focal subtle abnormalfindings seen on initial CT and MR images. CBV in the occluded arterial territory was lower in all eight patients;two had focal regions of increased CBV within the affected territory, indicating reperfusion hyperemia. In allpatients, regions of abnormal CBV were eventually converted to infarctions on follow-up images. CONCLUSION: Perfusion MR imaging was useful for the evaluation of hemodynamic change occurring during cerebral perfusion inhyperacute ischemic stroke, and prediction of the final extent of infarction. These results suggest that perfusionMR imaging can play an important role in the diagnosis and management of hyperacute ischemic stroke.


Assuntos
Humanos , Volume Sanguíneo , Artérias Cerebrais , Diagnóstico , Seguimentos , Hemodinâmica , Hiperemia , Infarto , Imageamento por Ressonância Magnética , Perfusão , Reperfusão , Acidente Vascular Cerebral , Tomografia Computadorizada por Raios X
19.
Journal of the Korean Radiological Society ; : 899-904, 1997.
Artigo em Coreano | WPRIM | ID: wpr-55688

RESUMO

PURPOSE: To describe the associated conditions and clinical significance of lenticulostriate uasculopathy (LSV) as demonstrated by cranial sonography. MATERIALS AND METHODS: We retrospectively studied 77 LSV cases who between January 1994 and January 1996 had undergone cranial sonography for neonatal asphyxia, seizure, or bulging of anterior fontanel. Cranial sonography was performed with 7 MHz real-time linear and sector transducers using an Acuson computed sonography unit ; examinations were performed in sagittal and coronal planes. Twenty-six LSV patients underwent color Doppler studies, and in 24 of these, color signal and arterial pulse spectral wave were detected. LSV was grouped as one of three types, according to echogenicity : type I (less echogenic than sylvian fissure), type II (similar to sylvian fissure), and type III (more echogenic than sylvian fissures). We retrospectively evaluated associated sonographic abnormalities of the brain, and reviewed medical records for associated conditions and neurologic sequelae. Follow-up sonographic examinations were performed in 23 patients. RESULTS: There were 56 type I cases (73 %), 17 of type II (22 %) and 4 of type III (5 %). Cranial sonographic results were normal in 36 cases (47 %) and abnormal in 41(53 %). Forty-eight cases of nonspecific causes and 29 cases of perinatal and acquired causes accounted for associated conditions. The echogenicity of LSV had not changed in 21 of 23 follow-up cases. Neurologic examinations were performed in 18 cases and in 14 of these (78 %) there was no neurologic sequela. CONCLUSION: LSV in basal ganglia may be associated with nonspecific neonatal conditions, in addition to well known perinatal causes.


Assuntos
Humanos , Asfixia , Gânglios da Base , Doença Cerebrovascular dos Gânglios da Base , Encéfalo , Fontanelas Cranianas , Seguimentos , Prontuários Médicos , Exame Neurológico , Estudos Retrospectivos , Convulsões , Transdutores , Ultrassonografia
20.
Journal of the Korean Radiological Society ; : 167-172, 1996.
Artigo em Coreano | WPRIM | ID: wpr-115260

RESUMO

PURPOSE: To evaluate the usefulness of dynamic contrast-enhanced T2*-weighted MR imaging for assessing cerebral hemodynamics in acute cerebral infarction. MATERIALS AND METHODS: We performed dynamic T2*-weighted imaging(TR/TE/flip angle : 40/26/10 degrees, 64 x 128 matrix, 5 sec scan time) in conjunction with conventional T1- andT2-weighted imaging and MR angiography in 20 patients with acute cerebral infarction. The regions of ischemia seenon T2-weighted image(high signal intensity), MR angiogram(vascular stenosis or occlusion) and dynamic contrast-enhanced T2*-weighted image(perfusion defect) were topographically compared with each other. Relative cerebral blood volumes(rCBVs) of the ischemic regions and of contralateral normal regions were calculated fromsignal intensity data measured on dynamic contrast-enhanced T2*-weighted images, and were compared. RESULTS: Regions of ischemia were topographically well correlated on T2-weighted image, MR angiogram and dynamic contrast-enhanced T2*-weighted image in all but two patients, of whom one had recanalization of the occluded artery and the other had a small infarction. rCBVs were asymmetrically reduced in the ischemic regions in all butone patient who had recanalization of the occluded artery. CONCLUSION: Dynamic contrast-enhanced T2*-weighted imaging is a useful method in the qualitative and quantitative assessment of cerebral hemodynamics in acutecerebral infarction. The use of this imaging technique along with conventional MR imaging and MR angiography provides better hemodynamic information in acute cerebral infarction.


Assuntos
Humanos , Angiografia , Artérias , Infarto Cerebral , Constrição Patológica , Hemodinâmica , Infarto , Isquemia , Imageamento por Ressonância Magnética
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