49 results match your criteria hypoperfused hyperperfused


Follow-Up of Brain Single-Photon Emission Computed Tomography (SPECT) and Magnetic Resonance Imaging (MRI) in a Case of Seizure Caused by Osmotic Demyelination Syndrome.

Am J Case Rep 2020 Jul 9;21:e923406. Epub 2020 Jul 9.

Department of Radiology, Chosun University Hospital, Gwangju, South Korea.

BACKGROUND Osmotic demyelination syndrome (ODS) is an uncommon neurological disorder. Until the mid-1980s, the mortality rate was 90-100%, but more than half of patients now have a good prognosis. Early suspicion of ODS is important. Read More

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Specificities of arterial spin labeling (ASL) abnormalities in acute seizure.

J Neuroradiol 2020 Feb 27;47(1):20-26. Epub 2018 Nov 27.

AP-HP, groupe hospitalier Pitié-Salpêtrière, neuroradiology department, 75013 Paris, France. Electronic address:

Purpose: Arterial spin labeling (ASL) is a non-invasive tool measuring cerebral blood flow (CBF) and is useful to assess acute neurological deficit. While acute stroke presents as hypoperfused vascular territory, epileptic activity causes cortical hyperperfusion. Other neurological conditions exhibit hyperperfusion, like migraine or secondary "luxury perfusion" in strokes. Read More

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February 2020

Differentiation of glioblastoma multiforme, metastases and primary central nervous system lymphomas using multiparametric perfusion and diffusion MR imaging of a tumor core and a peritumoral zone-Searching for a practical approach.

PLoS One 2018 17;13(1):e0191341. Epub 2018 Jan 17.

Department of General and Interventional Radiology and Neuroradiology, Wroclaw Medical University, Wroclaw, Poland.

Introduction: In conventional MR examinations glioblastomas multiforme (GBMs), metastases and primary CNS lymphomas (PCNSLs) may show very similar appearance. The aim of the study was to evaluate usefulness of multiparametric T2*DSC perfusion and diffusion MR imaging in the preoperative differentiation of these tumors.

Material And Methods: Seventy four solitary enhancing tumors (27 GBMs, 30 metastases, 17 PCNSLs) were enrolled in the study. Read More

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February 2018

Arterial Spin Labeling Cerebral Perfusion Magnetic Resonance Imaging in Migraine Aura: An Observational Study.

J Stroke Cerebrovasc Dis 2018 May 10;27(5):1262-1266. Epub 2018 Jan 10.

Department of Neurology, Universitätsmedizin Mannheim, University of Heidelberg, Mannheim, Germany; Department of Neurology, Klinikum Kempten, Kempten, Germany.

Background: Changes in cerebral perfusion during migraine with aura (MA) have been assessed mainly using dynamic susceptibility contrast (DSC) magnetic resonance perfusion imaging. A contrast agent-free method to assess these changes would be desirable. We assessed changes in cerebral perfusion during MA using arterial spin labeling (ASL) perfusion magnetic resonance imaging. Read More

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Connectivity in ictal single photon emission computed tomography perfusion: a cortico-cortical evoked potential study.

Brain 2017 Jul;140(7):1872-1884

Epilepsy Center, Cleveland Clinic Foundation, Cleveland, OH, USA.

Subtraction ictal and interictal single photon emission computed tomography can demonstrate complex ictal perfusion patterns. Regions with ictal hyperperfusion are suggested to reflect seizure onset and propagation pathways. The significance of ictal hypoperfusion is not well understood. Read More

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Arterial spin-labeling perfusion imaging of children with subdural hemorrhage: Perfusion abnormalities in abusive head trauma.

J Neuroradiol 2017 Jul 22;44(4):281-287. Epub 2017 Mar 22.

Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Keelung/Linkou, and Chang Gung University, Taiwan. Electronic address:

Background And Purpose: Perfusion abnormalities have not been well described in children with subdural hemorrhage (SDH). We investigated whether patients with abusive head trauma (AHT+) had more perfusion abnormalities than those without (AHT-).

Materials And Methods: We reviewed the perfusion MR studies of 12 infants with SDH and 21 controls. Read More

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Misleading early blood volume changes obtained using ferumoxytol-based magnetic resonance imaging perfusion in high grade glial neoplasms treated with bevacizumab.

Fluids Barriers CNS 2016 Dec 20;13(1):23. Epub 2016 Dec 20.

Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA.

Background: Neovascularization, a distinguishing trait of high-grade glioma, is a target for anti-angiogenic treatment with bevacizumab (BEV). This study sought to use ferumoxytol-based dynamic susceptibility contrast magnetic resonance imaging (MRI) to clarify perfusion and relative blood volume (rCBV) changes in glioma treated with BEV and to determine potential impact on clinical management.

Methods: 16 high grade glioma patients who received BEV following post-chemoradiation radiographic or clinical progression were included. Read More

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December 2016

Do perfusion and diffusion MRI predict glioblastoma relapse sites following chemoradiation?

J Neurooncol 2016 10 8;130(1):181-192. Epub 2016 Aug 8.

INSERM UMR 1214, TONIC (Toulouse NeuroImaging Centre), 31059, Toulouse, France.

To assess the value of T2* dynamic-susceptibility contrast MRI (DSC-MRI) and diffusion-weighted imaging (DWI) to predict the glioblastoma relapse sites after chemoradiation. From a cohort of 44 patients, primarily treated with radiotherapy (60 Gy) and concomitant temozolomide for glioblastoma, who were included in the reference arm of a prospective clinical trial (NCT01507506), 15 patients relapsed and their imaging data were analyzed. All patients underwent anatomical MRI, DSC-MRI and DWI before radiotherapy and every 2 months thereafter until relapse. Read More

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October 2016

OCT Angiography Compared to Fluorescein and Indocyanine Green Angiography in Chronic Central Serous Chorioretinopathy.

Invest Ophthalmol Vis Sci 2015 Aug;56(9):5229-37

Department of Ophthalmology Radboud University Medical Center, Nijmegen, The Netherlands.

Purpose: Abnormal choroidal blood flow is considered important in the pathogenesis of chronic central serous chorioretinopathy (CSC). Optical coherence tomography (OCT) angiography can image ocular blood cell flow and could thus provide novel insights in disease mechanisms of CSC. We evaluated depth-resolved flow in chronic CSC by OCT angiography compared to fluorescein angiography (FA) and indocyanine green angiography (ICGA). Read More

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Classification of tumor area using combined DCE and DSC MRI in patients with glioblastoma.

J Neurooncol 2015 Jan 5;121(2):349-57. Epub 2014 Nov 5.

Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, 6 Weizman St, 64239, Tel Aviv, Israel.

This study proposes an automatic method for identification and quantification of different tissue components: the non-enhanced infiltrative tumor, vasogenic edema and enhanced tumor areas, at the subject level, in patients with glioblastoma (GB) based on dynamic contrast enhancement (DCE) and dynamic susceptibility contrast (DSC) MRI. Nineteen MR data sets, obtained from 12 patients with GB, were included. Seven patients were scanned before and 8 weeks following bevacizumab initiation. Read More

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January 2015

Pediatric cerebral stroke: susceptibility-weighted imaging may predict post-ischemic malignant edema.

Neuroradiol J 2013 Oct 7;26(5):579-83. Epub 2013 Nov 7.

Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine; Baltimore, MD, USA -

Susceptibility-weighted imaging (SWI) is an advanced MRI technique providing information on the blood oxygenation level. Deoxyhemoglobin is increased in hypoperfused tissue characterized by SWI-hypointensity, while high oxyhemoglobin concentration within hyperperfused tissue results in a SWI iso- or hyperintensity compared to healthy brain tissue. We describe a child with a stroke, where SWI in addition to excluding hemorrhage and delineating the thrombus proved invaluable in determining regions of hyperperfusion or luxury perfusion, which contributed further to the prognosis including an increased risk of developing post-ischemic malignant edema. Read More

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October 2013

Subacute subdural hematoma.

Acta Neurochir Suppl 2013 ;118:143-6

Department of Neurosurgery, National Defense Medical College, Saitama, Japan.

Subacute subdural hematoma (SASDH) is a rare entity. We retrospectively reviewed 8 patients with SASDH. Four patients were male and 4 were female, with an age range of 45-87 years (mean, 67. Read More

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Perfusion magnetic resonance imaging characteristics of intracerebral tuberculomas and its role in differentiating tuberculomas from metastases.

Acta Radiol 2013 Apr 14;54(3):307-12. Epub 2013 Jan 14.

Department of Radiology, Seth GS Medical College and KEM Hospital, Thane, India.

Background: Intracerebral tuberculomas usually manifest as ring-enhancing of nodular lesions on magnetic resonance imaging (MRI). These imaging findings are also observed in other lesions like metastases and toxoplasmosis.

Purpose: To study the MRI perfusion characteristics of tuberculomas and its potential role in their definitive diagnosis. Read More

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Pulsed arterial spin-labeled MR imaging evaluation of tuberous sclerosis.

AJNR Am J Neuroradiol 2009 Apr 15;30(4):815-20. Epub 2009 Jan 15.

Department of Radiology, Wake Forest University, Winston-Salem, NC, USA.

Background And Purpose: Tuberous sclerosis presents with characteristic cortical hamartomas and subependymal nodules associated with seizures. The purpose of this study was to use pulsed arterial spin-labeling (PASL) to quantify the perfusion of the cortical hamartomas and correlate the perfusion values with seizure frequency.

Materials And Methods: A retrospective search yielded 16 MR imaging examinations including conventional MR imaging and PASL perfusion performed in 13 patients (age range, 7 months to 23 years) with a history of tuberous sclerosis. Read More

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Regional differences in the coupling between resting cerebral blood flow and metabolism may indicate action preparedness as a default state.

Cereb Cortex 2009 Feb 4;19(2):375-82. Epub 2008 Jun 4.

Section of Neuropsychiatry, Department of Psychiatry and the Philadelphia Veterans Administration Medical Center, University of Pennsylvania, Philadelphia, PA 19104-4283, USA.

Although most functional neuroimaging studies examine task effects, interest intensifies in the "default" resting brain. Resting conditions show consistent regional activity, yet oxygen extraction fraction constancy across regions. We compared resting cerebral metabolic rates of glucose (CMRgl) measured with 18F-labeled 2-fluoro-2-deoxy-D-glucose to cerebral blood flow (CBF) 15O-H2O measures, using the same positron emission tomography scanner in 2 samples (n = 60 and 30) of healthy right-handed adults. Read More

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February 2009

First experiences with contrast-enhanced first-pass MR perfusion imaging in patients with primary, benign cardiac masses and tumour-like lesions.

Eur Radiol 2008 Aug 15;18(8):1617-24. Epub 2008 Mar 15.

Department of Cardiovascular Imaging at Alice-Hospital, Darmstadt Radiology, Dieburger Strasse 29-31, 64287, Darmstadt, Germany.

The aim of this study was to evaluate the diagnostic value of contrast-enhanced first-pass perfusion MRI in patients with suspected cardiac masses and tumour-like lesions. Twenty patients underwent contrast-enhanced first-pass saturation-recovery steady-state-free-precession perfusion MRI in addition to clinical MRI. Eleven diagnostic parameters were analysed blinded in consensus by three observers: localisation (paracardiac/mural/intracavitary), malignancy (benign/malignant) and first-pass enhancement pattern (homogeneous/heterogeneous as well as non-perfused/hypoperfused/iso-perfused/ hyperperfused). Read More

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Arterial spin-labeling and MR spectroscopy in the differentiation of gliomas.

AJNR Am J Neuroradiol 2007 Oct 24;28(9):1683-9. Epub 2007 Sep 24.

Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.

Background And Purpose: Noninvasive grading of gliomas remains a challenge despite its important role in the prognosis and management of patients with intracranial neoplasms. In this study, we evaluated the ability of cerebral blood flow (CBF)-guided voxel-by-voxel analysis of multivoxel proton MR spectroscopic imaging ((1)H-MRSI) to differentiate low-grade from high-grade gliomas.

Materials And Methods: A total of 35 patients with primary gliomas (22 high grade and 13 low grade) underwent continuous arterial spin-labeling perfusion-weighted imaging (PWI) and (1)H-MRSI. Read More

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October 2007

[Nodular lesions of liver parenchyma caused by pathological vascularisation/perfusion].

Authors:
H-P Fischer H Zhou

Pathologe 2006 Jul;27(4):273-83

Institut für Pathologie, Universität Bonn, Sigmund-Freud-Strasse 25, 53127, Bonn.

Nodular regenerative hyperplasia (NRH) is characterized by a non-cirrhotic micronodular transformation of the liver parenchyma. It is based on the obliteration of small portal veins. Macroregenerative nodules (MRN) develop in areas of favourable blood flow in otherwise hypoperfused liver tissue. Read More

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Characterisation of focal liver lesions with contrast enhanced ultrasonography.

Eur J Radiol 2004 Jun;51 Suppl:S9-17

Innere Medizin 2, Caritas-Krankenhaus Bad Mergentheim, Uhlandstr. 7, 97980 Bad Mergentheim, Germany.

Ultrasound contrast agents (USCA) have improved the detection rate of liver tumours in recent years. Conventional ultrasound has been reported to be relatively unreliable in the characterisation of liver tumours. SonoVue (Bracco Imaging Spa) has been shown to be particularly advantageous in the differentiation of benign and malignant liver tumours and, therefore, possibly represents a new cost-effective competitive alternative to other liver imaging modalities (e. Read More

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[Improved detection and characterisation of liver tumors with echo-enhanced ultrasound].

Z Gastroenterol 2003 Dec;41(12):1167-76

Innere Medizin 2, Caritas-Krankenhaus Bad Mergentheim, Uhlandstr. 7, 97980 Bad Mergentheim, Germany.

Contrast-enhanced ultrasound techniques represent the most challenging efforts in recent ultrasound developments. Contrast-enhanced imaging of the liver will be reviewed with respect to the literature and our own experience. Echo-enhancing agents, also known as ultrasound contrast media, have improved the accuracy of liver ultrasound within recent years. Read More

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December 2003

Brain single photon emission computed tomographic evaluation of patients with childhood absence epilepsy.

J Child Neurol 2003 Aug;18(8):542-8

Department of Nuclear Medicine, Gazi University Faculty of Medicine, Ankara, Turkey.

This study was performed to determine the utility of 99mTc-hexamethylpropylenamine oxime (HMPAO) brain single photon emission computed tomography (SPECT) in evaluating patients with childhood absence epilepsy. Twenty-three patients (13 female, 10 male), aged 7 to 15 years (mean age 10.3 +/- 2. Read More

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Stroke: imaging and differential diagnosis.

Authors:
J C Baron

J Neural Transm Suppl 2002 (63):19-36

Department of Neurology and Stroke Unit, University of Cambridge, United Kingdom.

Structural and vascular imaging helps to differentiate haemorrhagic from acute ischemic stroke (AIS) and rule out non-stroke causes, as well as identify specific subtypes of stroke such as carotid dissection and venous thrombosis. However, it is negative in most AIS patients within 3-6 hrs of onset and thus does not allow efficient patient classification for management purposes. Physiologic neuroimaging with PET, SPECT and combined diffusion- and perfusion-weighted MR gives access to tissue perfusion and cell function/homeostasis. Read More

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Experience with 123I-iomazenil SPECT in acute cerebral infarction.

Nucl Med Commun 2002 Dec;23(12):1191-6

Department of Nuclear Medicine, University Hospital Hamburg-Eppendorf, Hamburg, Germany.

Neuronal cells are susceptible to cerebral ischaemia. As gamma-aminobutyric acid(A) (GABA(A)) receptors are specific for neurones, functional receptor imaging using I-iomazenil (IMZ), a ligand to the GABA benzodiazepine receptor, has been proposed as an imaging modality for the assessment of neuronal integrity. However, there is only limited experience with IMZ in patients with acute cerebral infarction. Read More

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December 2002

Effect of hyperventilation on cerebral blood flow in traumatic head injury: clinical relevance and monitoring correlates.

Crit Care Med 2002 Sep;30(9):1950-9

Division of Anaesthesia, University of cambridge, Addenbrooke's Hospital, Cambridge, UK.

Objective: To investigate the effect of hyperventilation on cerebral blood flow in traumatic brain injury.

Design: A prospective interventional study.

Setting: A specialist neurocritical care unit. Read More

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September 2002

Assessment of cerebral perfusion and cerebrovascular reserve in insulin-dependent diabetic patients without central neurological symptoms by means of 99mTc-HMPAO SPET with acetazolamide.

Eur J Nucl Med 2001 Nov;28(11):1647-55

Nuclear Medicine Service, University Hospital Marqués de Valdecilla, Avda. Valdecilla s/n, 39008 Santander, Spain.

The detection of subclinical abnormalities in cerebral blood flow could be of great value in identifying diabetic patients at risk of stroke. The aim of this study was to assess the contribution of semiquantified post-acetazolamide technetium-99m hexamethylpropylene amine oxime single-photon emission tomography (99mTc-HMPAO SPET) in 15 diabetic patients with no clinical history of central neurological disease. After baseline 99mTc-HMPAO SPET, a second SPET scan was acquired after activation of the cerebrovascular reserve (CVR) with an injection of 1 g of acetazolamide (post-ACZ SPET). Read More

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November 2001

Viable myocardium in reperfused acute myocardial infarction: rest and stress first-pass mr imaging.

J Korean Med Sci 2001 Jun;16(3):294-302

Department of Diagnostic Radiology, Ajou University Hospital, Suwon, Korea.

Feasibility of identifying viable myocardium in rest and stress magnetic resonance imaging (MRI) was evaluated using 3 hr occlusion and 30 min reperfusion model of left anterior descending (LAD) coronary artery in 12 felines. At rest MRI, viable myocardium confirmed by 2,3,5-triphenyl tetrazolium chloride (TTC)-staining showed rapid signal intensity (SI) rise followed by gradual decline not significantly different from normal myocardium that the two hyperperfused regions were distinguishable only from the hypoperfused nonviable myocardium. At stress MRI, hyperemia induced perfusion change was most pronounced in normal myocardium with earlier and greater peak enhancement followed by brisk 'washout' phase while minimally augmented enhancement in viable myocardium was still in 'washin' phase. Read More

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Echo-enhanced color- and power-Doppler EUS for the discrimination between focal pancreatitis and pancreatic carcinoma.

Gastrointest Endosc 2001 Jun;53(7):784-9

Department of Medicine I, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany.

Background: EUS is a precise method for detection and staging of pancreatic tumors. However, differentiation between inflammatory pseudotumor and pancreatic carcinoma remains difficult. The aim of this study was to evaluate contrast-enhanced EUS as a method of differentiating inflammation and carcinoma based on perfusion characteristics. Read More

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The localizing value of ictal SPECT in children with tuberous sclerosis complex and refractory partial epilepsy.

Epileptic Disord 1999 Mar;1(1):41-6

Neuroscience Program, Miami Children's Hospital, Florida 33155, USA.

Although multiple cortical tubers are a hallmark of tuberous sclerosis complex (TSC), seizures often originate from a single tuber, making excisional surgery a therapeutic option for intractable patients. To assess the role of ictal single photon emission computed tomography (SPECT) in defining the epileptogenic tuber, we reviewed videoelectroencephalography (V/EEG) data, magnetic resonance imaging (MRI) and SPECT scans of 15 patients (aged 3 months to 15 years, mean 5.1) with medically resistant partial seizures and TSC. Read More

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Cerebral blood flow and blood volume measured by magnetic resonance imaging bolus tracking after acute stroke in pigs: comparison with [(15)O]H(2)O positron emission tomography.

Stroke 2000 Aug;31(8):1958-64

PET-Center, Aarhus University Hospital, Denmark.

Background And Purpose: Early and accurate assessments of cerebral ischemia allow therapy to be tailored to individual stroke patients. We examined the feasibility of using a novel method for measuring cerebral blood flow (CBF) of ischemic tissue based on MRI after middle cerebral artery occlusion (MCAO). Moreover, the regional correlations between CBF and cerebral blood volume (CBV) were investigated in the regions with acute ischemic stroke. Read More

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[Comparison of modern diagnostic methods in children with intractable focal epilepsy].

Neurol Neurochir Pol 2000 ;34 Suppl 1:89-100

Klinika Obserwacyjno-Zakaźna, Akademia Medyczna im. Karola Marcinkowskiego w Poznaniu.

The basic aim of neuroimaging in children with intractable focal epilepsy is stablishing localization of epileptogenic zone. In this study 34 children (age 11-17 years) with intractable focal epilepsy were examined including: clinical history, physical examination, EEG, CT, MR, 99mTc-HMPAO SPECT. The hypoperfused region in interictal SPECT was concordant with clinical seizure characteristics in 22 children, with EEG in 13, with MR with 13 children. Read More

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