scholarly journals The Effect of Nimodipine on the Evolution of Human Cerebral Infarction Studied by PET

1989 ◽  
Vol 9 (4) ◽  
pp. 523-534 ◽  
Author(s):  
A. M. Hakim ◽  
A. C. Evans ◽  
L. Berger ◽  
H. Kuwabara ◽  
K. Worsley ◽  
...  
Keyword(s):  
Cerebral Blood Volume ◽  
Statistical Significance ◽  
Treated Group ◽  
Brain Regions ◽  
Normal Brain ◽  
Oxygen Extraction Ratio ◽  
Perfusion Measurement ◽  
Positron Emission ◽  
The Difference ◽  
Cortical Regions

Fourteen patients were studied by positron emission tomography (PET) within 48 h of onset of a hemispheric ischemic stroke and again 7 days later. After the first set of PET scans, the patients were randomized to receive either nimodipine (n = 7) or a carrier solution (n = 7) by intravenous infusion. The infusions were maintained until the end of the second PET studies. CBF, cerebral blood volume (CBV), oxygen extraction ratio (OER), CMRO2, and CMRglc were measured each time. These metabolic and perfusion measurements were performed by standard methods. A surface map of each metabolic and perfusion measurement in the cortical mantle was generated by interpolating between the available slices. The various surface maps representing the physiological characteristics determined in the same or subsequent studies were aligned so that all data sets could be analyzed identically using an array of square regions of interest (ROIs). The functional status of each ROI was recorded at the two intervals following the cerebrovascular accident to characterize the evolution of the infarct, penumbra, and normal brain regions. We presumed the ischemic penumbra to be cortical regions in the proximity of the infarct and perfused at CBF values between 12 and 18 ml/100 g/min on the first PET scan, while densely ischemic regions had CBF of <12 nl/100 g/min and normally perfused brain >18 ml/100 g/min. In the densely ischemic zone, CBF increased more in the nimodipine-treated group than in the carrier group. As well, in this region nimodipine reversed the decline in CMRO2 noted in the carrier group, the difference in the changes being significant. In the penumbra zone, comparable trends were noted in OER and CMRO2 but the difference in the changes between the two groups did not reach statistical significance. Changes in CMRglc and CBV were comparable between the two groups in both cortical regions.

scholarly journals Prolonged-release fampridine as adjunct therapy to active enabled motor training in multiple sclerosis patients: a pilot, double-blind, placebo-controlled study

2015 ◽  
Vol 42 (S1) ◽  
pp. S32-S33
Author(s):  
FH Jacques ◽  
A Schembri ◽  
A Nativ ◽  
C Paquette ◽  
P Kalinowski
Keyword(s):  
Statistical Significance ◽  
Treated Group ◽  
Controlled Study ◽  
Motor Training ◽  
Prolonged Release ◽  
Double Blind ◽  
Sit To Stand ◽  
Percent Improvement ◽  
The Difference ◽  
Multiple Sclerosis Patients

Objectives: To investigate if MS subjects treated with PRF 10mg BID will show a greater benefit from active enabled motor training compared with placebo. Methods: Single center, phase 4, pilot, placebo-controlled, double-blind 18 weeks study. Fifteen patients were randomized to receive PRF 10 mg BID and fifteen to received placebo BID. All patients participated in active enabled motor training of 3 sessions of 1 hour/week for 6 weeks. Patients were evaluated at -4, 0, 6 and 14 weeks using the timed 8 meters walk (8 MW), the 6 minute walk (6 MW) and the timed sit to stand (STS). Results: The PRF treated group achieved a higher mean percent improvement from baseline in all tasks at both 6 and 14 week time points. The difference reached statistical significance (mean difference of 14.29, p=0.046) for the 8MW at the 14 week time point. A higher incidence of responders (>20% improvement from baseline) was seen in the PRF treated group at 6 weeks on the 8MW (odds ratio [OR] of 2.31) and the 6MW (OR of 1.63), and at 14 weeks on the 8MW and the STS (OR of 2.0). Conclusions: PRF in MS patients appears to enhance the benefit of active enabled motor training and to better sustain it over the following 8 weeks.

scholarly journals Positron Emission Tomography in Minor Ischemic Stroke Using Oxygen-15 Steady-State Technique

1987 ◽  
Vol 7 (2) ◽  
pp. 137-142 ◽  
Author(s):  
C. Pozzilli ◽  
M. Itoh ◽  
T. Matsuzawa ◽  
H. Fukuda ◽  
Y. Abe ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Ischemic Stroke ◽  
Cerebral Blood Volume ◽  
Emission Tomography ◽  
Oxygen Extraction Ratio ◽  
Hemodynamic Compromise ◽  
Minor Ischemic Stroke ◽  
Positron Emission ◽  
Mild Disability ◽  
Normal Coupling

A study with positron emission tomography (PET) was performed on 10 patients with ischemic stroke and mild disability. The patients underwent cerebral angiography, x-ray computed tomography (CT) scan and regional cerebral measurements of CBF, CMRO2, oxygen extraction ratio (OER), and cerebral blood volume (CBV). Only minor arterial involvement was detected by angiography. In all patients, PET images of functional defects were more extensive than the corresponding CT hypodensity, and there were statistically significant reductions in CBF, CMRO2, and CBF/CBV ratio as compared with control subjects. Half of the regions analyzed in the affected hemisphere demonstrated a disruption of the normal coupling between CBF and CMRO2 as reflected by OER values significantly higher or lower than those of the corresponding region of the contralateral hemisphere. The pathophysiological pattern of high OER combined with a reduction in CBF proportionally greater than the reduction in CMRO2 was particularly indicative of regional chronic hemodynamic compromise in these patients.

scholarly journals Cerebral Blood Flow, Blood Volume, and Mean Transit Time Responses to Propofol and Indomethacin in Peritumor and Contralateral Brain Regions

2010 ◽  
Vol 112 (1) ◽  
pp. 50-56 ◽  
Author(s):  
Mads Rasmussen ◽  
Niels Juul ◽  
Søren M. Christensen ◽  
Kristjana Y. Jónsdóttir ◽  
Carsten Gyldensted ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Tumors ◽  
Blood Volume ◽  
Transit Time ◽  
Gray Matter ◽  
Cerebral Blood Volume ◽  
Mean Transit Time ◽  
Brain Regions ◽  
Normal Brain

Background The regional cerebral blood flow (CBF) response to propofol and indomethacin may be abnormal in patients with brain tumors. First, the authors tested the hypothesis that during propofol anesthesia alone and combined with indomethacin, changes in CBF, cerebral blood volume (CBV), and plasma mean transit time (MTT) differ in the peritumoral tissue compared with the contralateral normal brain region. Second, the authors tested the hypothesis that CBF and CBV are reduced and MTT is prolonged, in both regions during propofol anesthesia and indomethacin administration compared with propofol alone. Methods The authors studied eight patients subjected to craniotomy under propofol-fentanyl anesthesia for supratentorial brain tumors. Magnetic resonance imaging, including perfusion- and diffusion-weighted and structural sequences, was performed (1) on the day before surgery, (2) before and (3) after administration of indomethacin in the propofol-fentanyl anesthetized patient, and (4) 2 days after surgery. Maps of CBF, CBV, and MTT were calculated. The regions of interest were peritumoral gray matter and opposite contralateral gray matter. Analysis of variance was used to analyze flow data. Results Propofol anesthesia was associated with a median 32% (range, 3-61%) and 47% (range, 17-67%) reduction in CBF in the peritumoral and contralateral regions, respectively.The interaction between intervention with propofol and indomethacin and region of interest was not significant for any flow modalities. Neither intervention nor region was significant for MTT, CBF, and CBV (P &gt; 0.05). Conclusion The CBF, CBV, and MTT responses to propofol and indomethacin are not different in the peritumoral region compared with contralateral brain tissue. Indomethacin did not further influence regional CBF, CBV, and MTT during propofol anesthesia.

scholarly journals Different perceptual tasks performed with the same visual stimulus attribute activate different regions of the human brain: a positron emission tomography study

1993 ◽  
Vol 90 (23) ◽  
pp. 10927-10931 ◽  
Author(s):  
P Dupont ◽  
G A Orban ◽  
R Vogels ◽  
G Bormans ◽  
J Nuyts ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Human Brain ◽  
Brain Regions ◽  
Detection Task ◽  
Emission Tomography ◽  
Orientation Discrimination ◽  
Positron Emission ◽  
Passive Viewing ◽  
Cortical Regions ◽  
Visual Cortical

To investigate the processing of visual form in human cerebral cortex, we used the PET (positron emission tomography) activation technique to compare the human brain regions that are involved in a visual detection task and two orientation discrimination tasks: the temporal same-different (TSD) task, which includes a short-term memory component, and the identification (ID) task, which is without this component. As a control task we used passive viewing. Stimuli were identical in all four tasks. Subtraction of passive viewing from detection showed that the detection task activates early visual cortical regions (areas 17/18) as well as several motor brain regions, while decreasing activity in several higher order frontal, temporal, and parietal regions. Comparing the ID task to the detection task revealed no further visual cortical activation, while comparison of the TSD task to the detection task revealed an activation of several right visual cortical regions, one of which remained significant after the subtraction of ID from TSD (right area 19). These experiments demonstrate the task dependence of visual processing, even for very closely related tasks, and the localization of the temporal comparison component involved in orientation discrimination in human area 19.

Advanced magnetic resonance imaging and spectroscopy in a case of neurocysticercosis from North America

2021 ◽  
pp. 197140092110268
Author(s):  
Sanjeev Chawla ◽  
Shadi Asadollahi ◽  
Pradeep Kumar Gupta ◽  
Kavindra Nath ◽  
Steven Brem ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Cerebral Blood Volume ◽  
Taenia Solium ◽  
Parasitic Infection ◽  
Mean Diffusivity ◽  
Brain Regions ◽  
Resonance Spectroscopy ◽  
Normal Brain ◽  
Endemic Region ◽  
The Usa

Neurocysticercosis (NCC) is a parasitic infection caused by Cysticercus cellulosae, the metacestode of pork tapeworm ( Taenia solium). NCC is one of the most common public health problems worldwide. We present a patient harboring a bilobed ring-enhancing lesion with a presumed diagnosis of brain metastasis, who returned to the USA after traveling to an endemic region. The diagnosis of NCC was established based on a characteristic resonance of succinate on proton magnetic resonance spectroscopy. Also, higher mean diffusivity and lower fractional anisotropy along with relative cerebral blood volume were observed from the lesion compared to contralateral normal brain regions. Multiparametric analysis may improve the differential diagnosis of ring-enhancing intracranial lesions such as NCC.

Management of raised intracranial pressure

2010 ◽  
pp. 3147-3152
Author(s):  
David K. Menon
Keyword(s):  
Intracranial Pressure ◽  
Healthy Subjects ◽  
Cerebral Perfusion ◽  
Brain Oedema ◽  
Cerebral Blood Volume ◽  
Brain Perfusion ◽  
Normal Brain ◽  
Intracranial Volume ◽  
Nervous System Diseases ◽  
The Difference

Normal intracranial pressure (ICP) is between 5 and 15 mmHg in supine subjects. Intracranial hypertension (ICP >20 mmHg) is common in many central nervous system diseases and in fatal cases is often the immediate cause of death. Aetiology and pathogenesis—increases in intracranial volume and hence—given the rigid skull—ICP may be the consequence of (1) brain oedema, (2) increased cerebral blood volume, (3) hydrocephalus, and (4) space-occupying lesions. Brain perfusion depends on the difference between mean arterial pressure and ICP, termed cerebral perfusion pressure (CPP). The normal brain autoregulates cerebral blood flow down to a lower limit of CPP of about 50 mmHg in healthy subjects, and perhaps 60 to 70 mmHg in disease. CPP reduction to below these values results in cerebral ischaemia....

scholarly journals Topoisomerase IIIβ Deficiency Induces Neuro-Behavioral Changes and Brain Connectivity Alterations in Mice

2021 ◽  
Vol 22 (23) ◽  
pp. 12806
Author(s):  
Faiz Ur Rahman ◽  
You-Rim Kim ◽  
Eun-Kyeung Kim ◽  
Hae-rim Kim ◽  
Sang-Mi Cho ◽  
...  
Keyword(s):  
Olfactory Bulb ◽  
Brain Connectivity ◽  
Brain Regions ◽  
Normal Brain ◽  
Dna And Rna ◽  
Positron Emission ◽  
Normal Brain Function ◽  
Ct Analysis ◽  
The Central Nervous System ◽  
And Behavior

Topoisomerase IIIβ (Top3β), the only dual-activity topoisomerase in mammals that can change topology of both DNA and RNA, is known to be associated with neurodevelopment and mental dysfunction in humans. However, there is no report showing clear associations of Top3β with neuropsychiatric phenotypes in mice. Here, we investigated the effect of Top3β on neuro-behavior using newly generated Top3β deficient (Top3β−/−) mice. We found that Top3β−/− mice showed decreased anxiety and depression-like behaviors. The lack of Top3β was also associated with changes in circadian rhythm. In addition, a clear expression of Top3β was demonstrated in the central nervous system of mice. Positron emission tomography/computed tomography (PET/CT) analysis revealed significantly altered connectivity between many brain regions in Top3β−/− mice, including the connectivity between the olfactory bulb and the cerebellum, the connectivity between the amygdala and the olfactory bulb, and the connectivity between the globus pallidus and the optic nerve. These connectivity alterations in brain regions are known to be linked to neurodevelopmental as well as psychiatric and behavioral disorders in humans. Therefore, we conclude that Top3β is essential for normal brain function and behavior in mice and that Top3β could be an interesting target to study neuropsychiatric disorders in humans.

scholarly journals Estimation of Cerebral Oxygen Utilization Rate by Single-Bolus 15O2 Inhalation and Dynamic Positron Emission Tomography

1987 ◽  
Vol 7 (4) ◽  
pp. 403-414 ◽  
Author(s):  
E. Meyer ◽  
J. L. Tyler ◽  
C. J. Thompson ◽  
C. Redies ◽  
M. Diksic ◽  
...  
Keyword(s):  
Cerebral Blood Volume ◽  
Utilization Rate ◽  
Simultaneous Estimation ◽  
Oxygen Utilization ◽  
Oxygen Extraction Ratio ◽  
Time Activity ◽  
Single Bolus ◽  
Positron Emission ◽  
Tomographic Data ◽  
Oxygen Utilization Rate

This study shows that regional CMRO2 can be estimated by means of nonlinear regression using dynamic positron emission tomographic data acquired during 1 min following single-bolus inhalation of 15O2. The feasibility of simultaneous estimation of CBF, cerebral blood volume (CBV), oxygen extraction ratio (OER), and CMRO2 was assessed by simulations using the model of Mintun et al. Four oxygen metabolic measurements, each consisting of a CBF, CBV, and 15O2 bolus study, were carried out on three volunteers. Regional values for CBF, CBV, OER, and CMRO2 were derived in two ways: from the fits of the time-activity curves of the dynamic 15O2 bolus study alone [CMRO2(fit)] and from the three separate studies [CMRO2 (control)]. For the 56 regions of interest analyzed, using a fit interval of 60 s, CMRO2(fit) was 93.4 ± 7.8% of CMRO2(control) (mean ± SD) with a correlation coefficient of r = 0.95. CMRO2(control) ranged from 87 to 290 μmol/min/100 g. Individual simultaneous estimates of CBF, CBV, and OER were not reliable. Finally, we found that the validity of the model was limited in practice to the first minute after tracer inhalation.

scholarly journals Multimodal Imaging of Nonenhancing Glioblastoma Regions

2019 ◽  
Vol 18 ◽  
pp. 153601211988522 ◽  
Author(s):  
Flóra John ◽  
Natasha L. Robinette ◽  
Alit J. Amit-Yousif ◽  
Edit Bosnyák ◽  
Geoffrey R. Barger ◽  
...  
Keyword(s):  
Amino Acid ◽  
Multimodal Imaging ◽  
Cerebral Blood Volume ◽  
Structural Mri ◽  
Brain Regions ◽  
Tumor Mass ◽  
Positron Emission ◽  
Fluid Attenuated Inversion Recovery ◽  
Amino Acid Pet ◽  
Magnetic Resonance Imaging Mri

Background: Clinical glioblastoma treatment mostly focuses on the contrast-enhancing tumor mass. Amino acid positron emission tomography (PET) can detect additional, nonenhancing glioblastoma-infiltrated brain regions that are difficult to distinguish on conventional magnetic resonance imaging (MRI). We combined MRI with perfusion imaging and amino acid PET to evaluate such nonenhancing glioblastoma regions. Methods: Structural MRI, relative cerebral blood volume (rCBV) maps from perfusion MRI, and α-[11C]-methyl-l-tryptophan (AMT)-PET images were analyzed in 20 patients with glioblastoma. The AMT uptake and rCBV (expressed as tumor to normal [T/N] ratios) were compared in nonenhancing tumor portions showing increased signal on T2/fluid-attenuated inversion recovery (T2/FLAIR) images. Results: Thirteen (65%) tumors showed robust heterogeneity in nonenhancing T2/FLAIR hyperintense areas on AMT-PET, whereas the nonenhancing regions in the remaining 7 cases had homogeneous AMT uptake (low in 6, high in 1). AMT and rCBV T/N ratios showed only a moderate correlation in the nonenhancing regions ( r = 0.41, P = .017), but regions with very low rCBV (<0.79 T/N ratio) had invariably low AMT uptake. Conclusions: The findings demonstrate the metabolic and perfusion heterogeneity of nonenhancing T2/FLAIR hyperintense glioblastoma regions. Amino acid PET imaging of such regions can detect glioma-infiltrated brain for treatment targeting; however, very low rCBV values outside the contrast-enhancing tumor mass make increased AMT uptake in nonenhancing glioblastoma regions unlikely.

Cortical Regions Associated with Perceiving, Naming, and Knowing about Colors

1999 ◽  
Vol 11 (1) ◽  
pp. 25-35 ◽  
Author(s):  
Linda L. Chao ◽  
Alex Martin
Keyword(s):  
Color Perception ◽  
Brain Regions ◽  
Gray Scale ◽  
Brain Areas ◽  
Low Level ◽  
Positron Emission ◽  
Specific Object ◽  
Cortical Regions ◽  
Object Form ◽  
Parietal Cortices

Positron emission tomography (PET) was used to investigate whether retrieving information about a specific object attribute requires reactivation of brain areas that mediate perception of that attribute. During separate PET scans, subjects passively viewed colored and equiluminant gray-scale Mondrians, named colored and achromatic objects, named the color of colored objects, and generated color names associated with achromatic objects. Color perception was associated with activations in the lingual and fusiform gyri of the occipital lobes, consistent with previous neuroimaging and human lesion studies. Retrieving information about object color (generating color names for achromatic objects relative to naming achromatic objects) activated the left inferior temporal, left frontal, and left posterior parietal cortices, replicating previous findings from this laboratory. When subjects generated color names for achromatic objects relative to the low-level baseline of viewing gray-scale Mondrians, additional activations in the left fusi-form/lateral occipital region were detected. However, these activations were lateral to the occipital regions associated with color perception and identical to occipital regions activated when subjects simply named achromatic objects relative to the same low-level baseline. This suggests that the occipital activa-tions associated with retrieving color information were due to the perception of object form rather than to the top-down influence of brain areas that mediate color perception. Taken together, these results indicate that retrieving previously acquired information about an object's typical color does not require reactivation of brain regions that subserve color perception.

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