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Sample records for cerebral perfusion pressure

  1. Perfusion Pressure Cerebral Infarct (PPCI) trial

    DEFF Research Database (Denmark)

    Vedel, Anne G.; Holmgaard, Frederik; Rasmussen, Lars Simon

    2016-01-01

    to be 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 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...

  2. Enhanced Visualization of Optimal Cerebral Perfusion Pressure Over Time to Support Clinical Decision Making

    NARCIS (Netherlands)

    Aries, Marcel J H; Wesselink, Robin; Elting, Jan Willem J; Donnelly, Joseph; Czosnyka, Marek; Ercole, Ari; Maurits, Natasha M; Smielewski, Peter

    2016-01-01

    OBJECTIVE: Cerebrovascular reactivity can provide a continuously updated individualized target for management of cerebral perfusion pressure, termed optimal cerebral perfusion pressure. The objective of this project was to find a way of improving the optimal cerebral perfusion pressure methodology b

  3. Optimal Cerebral Perfusion Pressure Management at Bedside : A Single-Center Pilot Study

    NARCIS (Netherlands)

    Dias, Celeste; Silva, Maria Joao; Pereira, Eduarda; Monteiro, Elisabete; Maia, Isabel; Barbosa, Silvina; Silva, Sofia; Honrado, Teresa; Cerejo, Antonio; Aries, Marcel J. H.; Smielewski, Peter; Paiva, Jose-Artur; Czosnyka, Marek

    2015-01-01

    Guidelines recommend cerebral perfusion pressure (CPP) values of 50-70 mmHg and intracranial pressure lower than 20 mmHg for the management of acute traumatic brain injury (TBI). However, adequate individual targets are still poorly addressed, since patients have different perfusion thresholds. Beds

  4. Clinical and Physiological Events That Contribute to the Success Rate of Finding "Optimal" Cerebral Perfusion Pressure in Severe Brain Trauma Patients

    NARCIS (Netherlands)

    Weersink, Corien S. A.; Aries, Marcel J. H.; Dias, Celeste; Liu, Mary X.; Kolias, Angelos G.; Donnelly, Joseph; Czosnyka, Marek; van Dijk, J. Marc C.; Regtien, Joost; Menon, David K.; Hutchinson, Peter J.; Smielewski, Peter

    2015-01-01

    Objective: Recently, a concept of an individually targeted level of cerebral perfusion pressure that aims to restore impaired cerebral vasoreactivity has been advocated after traumatic brain injury. The relationship between cerebral perfusion pressure and pressure reactivity index normally is suppos

  5. Carotid artery disease and low cerebral perfusion pressure

    DEFF Research Database (Denmark)

    Schroeder, T; Utzon, N P; Aabech, J

    1990-01-01

    Direct internal carotid artery blood pressure measurements in patients undergoing carotid endarterectomy identified 49 patients, among 239 consecutive cases (21%), who had a reduction in perfusion pressure of 20% or more. The clinical history, objective findings and angiographic data were compared...... with those of a control group of a further 49 patients selected from the remaining patients operated on over the same period. The two groups were compared for short- and long-term outcome of surgery. We were unable to delineate a symptomatic neurological profile that identified patients with low perfusion...... pressures. Surgery in patients with low perfusion pressures seemed to be associated with an increased complication rate (12% versus 4%), although this was not statistically significant. Definite postoperative improvements in persisting neurological deficits were observed only in one patient. Long...

  6. Carbon dioxide induced changes in cerebral blood flow and flow velocity: Role of cerebrovascular resistance and effective cerebral perfusion pressure

    NARCIS (Netherlands)

    F. Grüne (Frank); S. Kazmaier (Stephan); R.J. Stolker (Robert J.); G.H. Visser (Gerhard Henk); A. Weyland (Andreas)

    2015-01-01

    textabstractIn addition to cerebrovascular resistance (CVR) zero flow pressure (ZFP), effective cerebral perfusion pressure (CPPe) and the resistance area product (RAP) are supplemental determinants of cerebral blood flow (CBF). Until now, the interrelationship of PaCO2 -induced changes in CBF, CVR,

  7. Carbon dioxide induced changes in cerebral blood flow and flow velocity: role of cerebrovascular resistance and effective cerebral perfusion pressure.

    Science.gov (United States)

    Grüne, Frank; Kazmaier, Stephan; Stolker, Robert J; Visser, Gerhard H; Weyland, Andreas

    2015-09-01

    In addition to cerebrovascular resistance (CVR) zero flow pressure (ZFP), effective cerebral perfusion pressure (CPPe) and the resistance area product (RAP) are supplemental determinants of cerebral blood flow (CBF). Until now, the interrelationship of PaCO2-induced changes in CBF, CVR, CPPe, ZFP, and RAP is not fully understood. In a controlled crossover trial, we investigated 10 anesthetized patients aiming at PaCO2 levels of 30, 37, 43, and 50 mm Hg. Cerebral blood flow was measured with a modified Kety-Schmidt-technique. Zero flow pressure and RAP was estimated by linear regression analysis of pressure-flow velocity relationships of the middle cerebral artery. Effective cerebral perfusion pressure was calculated as the difference between mean arterial pressure and ZFP, CVR as the ratio CPPe/CBF. Statistical analysis was performed by one-way RM-ANOVA. When comparing hypocapnia with hypercapnia, CBF showed a significant exponential reduction by 55% and mean VMCA by 41%. Effective cerebral perfusion pressure linearly decreased by 17% while ZFP increased from 14 to 29 mm Hg. Cerebrovascular resistance increased by 96% and RAP by 39%; despite these concordant changes in mean CVR and Doppler-derived RAP correlation between these variables was weak (r=0.43). In conclusion, under general anesthesia hypocapnia-induced reduction in CBF is caused by both an increase in CVR and a decrease in CPPe, as a consequence of an increase in ZFP.

  8. Middle cerebral artery occlusion in presence of low perfusion pressure increases infarct size in rats

    DEFF Research Database (Denmark)

    Sillesen, H; Nedergaard, Majken; Schroeder, T;

    1988-01-01

    A model was set up in order to evaluate the importance of hemispheric perfusion pressure when the middle cerebral artery (MCA) is occluded in anaesthetized rats. In 6 animals the internal carotid artery (ICA) was occluded prior to ipsilateral MCA occlusion; in 17 animals the MCA only was occluded...

  9. Postural influence on intracranial and cerebral perfusion pressure in ambulatory neurosurgical patients

    DEFF Research Database (Denmark)

    Petersen, Lonnie Grove; Petersen, Johan Casper Grove; Andresen, Morten;

    2016-01-01

    We evaluated postural effects on intracranial pressure (ICP) and cerebral perfusion pressure (CPP: mean arterial pressure (MAP) - ICP) in neurosurgical patients undergoing 24-hour ICP monitoring as part of their diagnostic workup. We identified 9 patients (5 women, age 44±20 yrs.; mean±SD) who were...... "as normal as possible" i.e. without indication for neurosurgical intervention (e.g. focal lesions, global edema, abnormalities in ICP-profile or cerebrospinal fluid dynamics). ICP (tip-transducer probe, Raumedic) in the brain parenchyma (N=7) or in the lateral ventricles (N=2) and cardiovascular...

  10. Intracranial pressure and cerebral perfusion pressure monitoring in non-TBI patients: special considerations.

    Science.gov (United States)

    Helbok, Raimund; Olson, DaiWai M; Le Roux, Peter D; Vespa, Paul

    2014-12-01

    The effect of intracranial pressure (ICP) and the role of ICP monitoring are best studied in traumatic brain injury (TBI). However, a variety of acute neurologic illnesses e.g., subarachnoid hemorrhage, intracerebral hemorrhage, ischemic stroke, meningitis/encephalitis, and select metabolic disorders, e.g., liver failure and malignant, brain tumors can affect ICP. The purpose of this paper is to review the literature about ICP monitoring in conditions other than TBI and to provide recommendations how the technique may be used in patient management. A PubMed search between 1980 and September 2013 identified 989 articles; 225 of which were reviewed in detail. The technique used to monitor ICP in non-TBI conditions is similar to that used in TBI; however, indications for ICP monitoring often are intertwined with the presence of obstructive hydrocephalus and hence the use of ventricular catheters is more frequent. Increased ICP can adversely affect outcome, particularly when it fails to respond to treatment. However, patients with elevated ICP can still have favorable outcomes. Although the influence of ICP-based care on outcome in non-TBI conditions appears less robust than in TBI, monitoring ICP and cerebral perfusion pressure can play a role in guiding therapy in select patients.

  11. Intrathoracic Pressure Regulation Improves Cerebral Perfusion and Cerebral Blood Flow in a Porcine Model of Brain Injury.

    Science.gov (United States)

    Metzger, Anja; Rees, Jennifer; Kwon, Young; Matsuura, Timothy; McKnite, Scott; Lurie, Keith G

    2015-08-01

    Brain injury is a leading cause of death and disability in children and adults in their most productive years. Use of intrathoracic pressure regulation (IPR) to generate negative intrathoracic pressure during the expiratory phase of positive pressure ventilation improves mean arterial pressure and 24-h survival in porcine models of hemorrhagic shock and cardiac arrest and has been demonstrated to decrease intracranial pressure (ICP) and cerebral perfusion pressure (CPP) in these models. Application of IPR for 240 min in a porcine model of intracranial hypertension (ICH) will increase CPP when compared with controls. Twenty-three female pigs were subjected to focal brain injury by insertion of an epidural Foley catheter inflated with 3 mL of saline. Animals were randomized to treatment for 240 min with IPR set to a negative expiratory phase pressure of -12 cmH2O or no IPR therapy. Intracranial pressure, mean arterial pressure, CPP, and cerebral blood flow (CBF) were evaluated. Intrathoracic pressure regulation significantly improved mean CPP and CBF. Specifically, mean CPP after 90, 120, 180, and 240 min of IPR use was 43.7 ± 2.8 mmHg, 44.0 ± 2.7 mmHg, 44.5 ± 2.8 mmHg, and 43.1 ± 1.9 mmHg, respectively; a significant increase from ICH study baseline (39.5 ± 1.7 mmHg) compared with control animals in which mean CPP was 36.7 ± 1.4 mmHg (ICH study baseline) and then 35.9 ± 2.1 mmHg, 33.7 ± 2.8 mmHg, 33.9 ± 3.0 mmHg, and 36.0 ± 2.7 mmHg at 90, 120, 180, and 240 min, respectively (P blood flow, as measured by an invasive CBF probe, increased in the IPR group (34 ± 4 mL/100 g-min to 49 ± 7 mL/100 g-min at 90 min) but not in controls (27 ± 1 mL/100 g-min to 25 ± 5 mL/100 g-min at 90 min) (P = 0.01). Arterial pH remained unchanged during the entire period of IPR compared with baseline values and control values. In this anesthetized pig model of ICH, treatment with IPR significantly improved CPP and CBF. This therapy may be of clinical value by noninvasively

  12. Sumatriptan and cerebral perfusion in healthy volunteers.

    Science.gov (United States)

    Scott, A K; Grimes, S; Ng, K; Critchley, M; Breckenridge, A M; Thomson, C; Pilgrim, A J

    1992-04-01

    1. The effect of sumatriptan on regional cerebral perfusion was studied in healthy volunteers. 2. Intravenous sumatriptan (2 mg) had no detectable effect on regional cerebral perfusion as measured using a SPECT system with 99technetiumm labelled hexemethylpropyleneamineoxime. 3. Sumatriptan had no effect on pulse, blood pressure or ECG indices. 4. All six volunteers experienced minor adverse effects during the intravenous infusion.

  13. Cerebral hemodynamics in aging : the interplay between blood pressure, cerebral perfusion, and dementia

    NARCIS (Netherlands)

    Claassen, J.A.H.R.

    2008-01-01

    Advances in measurement techniques have made it possible to study dynamic changes in brain blood flow. Transcranial Doppler ultrasonography measures changes in cerebral blood flow-velocity in the larger cerebral arteries (e.g. the middle cerebral artery). Near infrared spectroscopy records changes i

  14. Effect of propofol and thiopentone on intracranial pressure and cerebral perfusion pressure in patients undergoing elective craniotomy - a comparative study

    Directory of Open Access Journals (Sweden)

    Sankari Santra

    2007-01-01

    Full Text Available Advantages and disadvantages of newer agent like propofol need to be evaluated with time tested inducing drug - thiopentone in neuroanaesthesia. The aim of the study was to compare effects of propofol with thiopentone on intracranial pressure, cerebral perfusion pressure and haemodynamics during induction in neurosurgical pa-tients. Fifty adult patients of ASA grade I& II scheduled for elective craniotomy were randomly assigned to receive induction of anaesthesia with either propofol 1.5-2.5 mg.kg -1 i.v. (Group A, n=25 or thiopentone 4-5 mg.kg -1 , i.v. (Group B, n=25. Vecuronium bromide 0.1 mg.kg -1 i.v. was used as intubating muscle relaxant. Both groups received fentanyl 2 pg.kg -1 i.v., lidocaine(preservative free 1.5 mg.kg -1 i.v. and supplementary dose of same inducing agent before intubation. Changes in mean arterial pressure (MAP, cerebrospinal fluid pressure (CSFP, cerebral perfusion pressure (CPP and heart rate (HR were noted during induction and endotracheal intubation. On statistical analysis it was found that CSFP decreased significantly (P< 0.001 in both groups after induction but endotracheal intubation did not provoke any significant rise in CSFP. Maximum decrease of CSFP was 35.26% in Group A and 35.20% in Group B. Fall in MAP was more significant in Group A (P< 0.001, as a result CPP was significantly less in Group A than in Group B. The lowest mean CPP (71.12±5.86 mm Hg was observed 2 minutes after induction dose in Group A when maximum drop in MAP occurred. Heart rate did not change significantly in Group A but in Group B fluctuation of heart rate was more.

  15. Cerebral perfusion pressure and risk of brain hypoxia in severe head injury: a prospective observational study

    Science.gov (United States)

    Marín-Caballos, Antonio J; Murillo-Cabezas, Francisco; Cayuela-Domínguez, Aurelio; Domínguez-Roldán, Jose M; Rincón-Ferrari, M Dolores; Valencia-Anguita, Julio; Flores-Cordero, Juan M; Muñoz-Sánchez, M Angeles

    2005-01-01

    Introduction Higher and lower cerebral perfusion pressure (CPP) thresholds have been proposed to improve brain tissue oxygen pressure (PtiO2) and outcome. We study the distribution of hypoxic PtiO2 samples at different CPP thresholds, using prospective multimodality monitoring in patients with severe traumatic brain injury. Methods This is a prospective observational study of 22 severely head injured patients admitted to a neurosurgical critical care unit from whom multimodality data was collected during standard management directed at improving intracranial pressure, CPP and PtiO2. Local PtiO2 was continuously measured in uninjured areas and snapshot samples were collected hourly and analyzed in relation to simultaneous CPP. Other variables that influence tissue oxygen availability, mainly arterial oxygen saturation, end tidal carbon dioxide, body temperature and effective hemoglobin, were also monitored to keep them stable in order to avoid non-ischemic hypoxia. Results Our main results indicate that half of PtiO2 samples were at risk of hypoxia (defined by a PtiO2 equal to or less than 15 mmHg) when CPP was below 60 mmHg, and that this percentage decreased to 25% and 10% when CPP was between 60 and 70 mmHg and above 70 mmHg, respectively (p < 0.01). Conclusion Our study indicates that the risk of brain tissue hypoxia in severely head injured patients could be really high when CPP is below the normally recommended threshold of 60 mmHg, is still elevated when CPP is slightly over it, but decreases at CPP values above it. PMID:16356218

  16. The effects of sevoflurane and isoflurane on intracranial pressure and cerebral perfusion pressure after diffuse brain injury in rats.

    Science.gov (United States)

    Goren, S; Kahveci, N; Alkan, T; Goren, B; Korfali, E

    2001-04-01

    Twenty-four adult male Wistar rats, weighing 220 to 290 g, were anesthetized with 30 mg/kg intraperitoneal sodium thiopental, then underwent a tracheostomy. After diffuse impact-acceleration brain injury (BI) was induced, each rat was paralyzed and mechanically ventilated with 30% O2 in nitrous oxide (N2O). The rats were assigned randomly to two groups, each of which received one of the two volatile anesthetic agents, sevoflurane or isoflurane. The anesthetics were administered at 0.5, 0.75, 1.0, and 1.25 minimal alveolar concentration (MAC) for 30 minutes each, respectively, and anesthesia was maintained at 0.75 MAC during the last hour of the study period. Intracranial pressure (ICP), mean arterial pressure (MAP), rectal and intrahemispheric temperatures, and end-tidal volatile anesthetic concentrations were monitored continuously throughout the 3 hours, with measurements recorded every 15 minutes. At baseline, there were no significant differences between the two groups regarding the monitored physiologic values. In the sevoflurane group, MAP fell significantly after 45 minutes, and a similar change was observed in the isoflurane group after 30 minutes (P pressure increased significantly at 45 minutes in the sevoflurane group (P isoflurane group, the change was not significant. Cerebral perfusion pressure (CPP) decreased in parallel with MAP, with the reduction in the sevoflurane group being more pronounced than that in the isoflurane group. The results demonstrated that, under the conditions of diffuse BI, animals that were anesthetized with sevoflurane had higher ICP and lower CPP levels than those anesthetized with isoflurane.

  17. Intraoperative blood pressure and cerebral perfusion: strategies to clarify hemodynamic goals.

    Science.gov (United States)

    Williams, Monica; Lee, Jennifer K

    2014-07-01

    Blood pressure can vary considerably during anesthesia. If blood pressure falls outside the limits of cerebrovascular autoregulation, children can become at risk of cerebral ischemic or hyperemic injury. However, the blood pressure limits of autoregulation are unclear in infants and children, and these limits can shift after brain injury. This article will review autoregulation, considerations for the hemodynamic management of children with brain injuries, and research on autoregulation monitoring techniques.

  18. Intraoperative blood pressure and cerebral perfusion: strategies to clarify hemodynamic goals

    OpenAIRE

    Williams, Monica; Lee, Jennifer K.

    2014-01-01

    Blood pressure can vary considerably during anesthesia. If blood pressure falls outside the limits of cerebrovascular autoregulation, children can become at risk of cerebral ischemic or hyperemic injury. However, the blood pressure limits of autoregulation are unclear in infants and children, and these limits can shift after brain injury. This article will review autoregulation, considerations for the hemodynamic management of children with brain injuries, and research on autoregulation monit...

  19. The Effect of Equal Ratio Ventilation on Oxygenation, Respiratory Mechanics, and Cerebral Perfusion Pressure During Laparoscopy in the Trendelenburg Position.

    Science.gov (United States)

    Jo, Youn Yi; Kim, Ji Young; Chang, Young Jin; Lee, Sehwan; Kwak, Hyun Jeong

    2016-06-01

    The aim of this study was to investigate the effects of equal ratio ventilation (ERV) on oxygenation, respiratory mechanics, and the cerebral perfusion pressure during pneumoperitoneum in the Trendelenburg position. Thirty patients undergoing laparoscopic low anterior resection (25 to 65 y) were enrolled. Mechanical ventilator was set to volume-controlled mode at an inspiratory to expiratory (I:E) ratio of 1:2 with a tidal volume of 8 mL/kg of ideal body weight with a 5 cm H2O positive end-expiratory pressure. Twenty minutes after pneumoperitoneum in the Trendelenburg position, the I:E ratio was changed to 1:1 for 20 minutes and then restored to 1:2. No significant changes in arterial oxygen tension and respiratory compliance after adopting ERV. Mean arterial pressure and cerebral perfusion pressure decreased significantly over time after adopting the Trendelenburg position during pneumoperitoneum (P=0.014 and 0.005, respectively). In conclusion, there was no improvement in oxygenation or respiratory mechanics with ERV.

  20. CBF/CBV maps in normal volunteers studied with (15)O PET: a possible index of cerebral perfusion pressure.

    Science.gov (United States)

    Watabe, Tadashi; Shimosegawa, Eku; Kato, Hiroki; Isohashi, Kayako; Ishibashi, Mana; Hatazawa, Jun

    2014-10-01

    Local cerebral perfusion pressure (CPP) is a primary factor controlling cerebral circulation and previous studies have indicated that the ratio of cerebral blood flow (CBF) to cerebral blood volume (CBV) can be used as an index of the local CPP. In this study, we investigated whether the CBF/CBV ratio differs among different brain structures under physiological conditions, by means of (15)O positron emission tomography. Nine healthy volunteers (5 men and 4 women; mean age, 47.0 ± 1.2 years) were studied by H2 (15)O bolus injection for CBF measurement and by C(15)O inhalation for CBV measurement. The CBF/CBV ratio maps were created by dividing the CBF images by the CBV images after anatomical normalization. Regions of interest were placed on the CBF/CBV maps and comparing the regions. The mean CBF/CBV ratio was highest in the cerebellum (19.3 ± 5.2/min), followed by the putamen (18.2 ± 3.9), pons (16.4 ± 4.6), thalamus (14.5 ± 3.3), cerebral cortices (13.2 ± 2.4), and centrum semiovale (11.5 ± 2.1). The cerebellum and putamen showed significantly higher CBF/CBV ratios than the cerebral cortices and centrum semiovale. We created maps of the CBF/CBV ratio in normal volunteers and demonstrated higher CBF/CBV ratios in the cerebellum and putamen than in the cerebral cortices and deep cerebral white matter. The CBF/CBV may reflect the local CPP and should be studied in hemodynamically compromised patients and in patients with risk factors for small-artery diseases of the brain.

  1. Effects of Blood Pressure Fluctuations on Cerebral Perfusion after Ischemic Stroke%血压波动对脑梗死后脑灌注的影响

    Institute of Scientific and Technical Information of China (English)

    聂志余; 靳令经

    2011-01-01

    Cerebral infarction affects both cerebral autoregulation and cerebral perfusion. This review article summarizes the published evidence of cerebral autoregulation impairment and cerebral blood flow alteration after cerebral infarction, including cerebrovascular small vessel disease leading to an impairment of vasoreactivity, blood flow velocities and cerebral blood flow associated positively with systemic blood pressure, perfusion declined on the infarcted side and lower blood pressure resulting in hypoperfusion in distal area of the narrowing main cerebral artery. The question should be thought by physicians about what is the 'best blood pressure range' in patients with cerebral infarction and it will be benefit for optimal recovery.%本文主要从脑血管的自动调节与自动调节受损、脑小血管病变可导致脑血管反应性受损、脑梗死患者脑血流速度、脑血流量与血压的相关性,脑梗死侧大脑半球脑灌注降低、低血压对脑主要动脉狭窄者可导致狭窄远端脑组织局部低灌注等几个方面来讨论脑梗死后血压的变化对脑血流速度、脑血流量的影响.给临床医生提出一个思考问题,在脑梗死的急性期把血压控制在多少才是最合适的水平,对患者的功能恢复最有益.

  2. 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...

  3. Intracranial Pressure Monitoring: Relationship Between Indices of Cerebrovascular Reserve, System Bandwidth, and Cerebral Perfusion

    Science.gov (United States)

    2007-11-02

    reactivity index ( PrX ), derived from correlation of the dynamic features of the intracranial pressure (ICP) and arterial blood pressure (ABP...brain has lost the ability to regulate blood flow, these pressure signals are similar [1,2]. The PrX index is numerically derived from the correlation

  4. Intracranial pressure monitoring, cerebral perfusion pressure estimation, and ICP/CPP-guided therapy: a standard of care or optional extra after brain injury?

    Science.gov (United States)

    Kirkman, M A; Smith, M

    2014-01-01

    Measurement of intracranial pressure (ICP) and mean arterial pressure (MAP) is used to derive cerebral perfusion pressure (CPP) and to guide targeted therapy of acute brain injury (ABI) during neurointensive care. Here we provide a narrative review of the evidence for ICP monitoring, CPP estimation, and ICP/CPP-guided therapy after ABI. Despite its widespread use, there is currently no class I evidence that ICP/CPP-guided therapy for any cerebral pathology improves outcomes; indeed some evidence suggests that it makes no difference, and some that it may worsen outcomes. Similarly, no class I evidence can currently advise the ideal CPP for any form of ABI. 'Optimal' CPP is likely patient-, time-, and pathology-specific. Further, CPP estimation requires correct referencing (at the level of the foramen of Monro as opposed to the level of the heart) for MAP measurement to avoid CPP over-estimation and adverse patient outcomes. Evidence is emerging for the role of other monitors of cerebral well-being that enable the clinician to employ an individualized multimodality monitoring approach in patients with ABI, and these are briefly reviewed. While acknowledging difficulties in conducting robust prospective randomized studies in this area, such high-quality evidence for the utility of ICP/CPP-directed therapy in ABI is urgently required. So, too, is the wider adoption of multimodality neuromonitoring to guide optimal management of ICP and CPP, and a greater understanding of the underlying pathophysiology of the different forms of ABI and what exactly the different monitoring tools used actually represent.

  5. Cerebral perfusion SPECT in transient ischemic attack

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    You, D.-L. E-mail: dlyou@mail.kfcc.org.tw; Shieh, F.-Y.; Tzen, K.-Y.; Tsai, M.-F.; Kao, P.-F

    2000-04-01

    Purpose: The purpose of our study is to evaluate the efficacy of cerebral perfusion single photon emission computerized tomography (SPECT) in patients with transient ischemic attack (TIA). Methods: Thirty-seven patients with TIA were collected for study. All patients had transient focal neurological symptoms or signs with complete recovery within 24 h after onset. The patients underwent cerebral perfusion SPECT between 6 h and 11 days after onset, with 10 cases performed within 24 h (group A), nine cases performed between 1 and 3 days (group B), 11 cases performed between 3 and 5 days (group C), and seven cases performed after more than 5 days (group D). A semi-quantitative method was used for analyzing the SPECT data, and the difference ratios between lesion side and contralateral normal side were calculated on each pair of regions of interest. Results: In total, 78.4% (29/37) of patients had reduced perfusion in the cerebral cortical regions or deep nuclei, and the regions with reduced perfusion corresponded with clinical presentations of the patients. The abnormal rate with reduced perfusion was 90.0% in group A, 77.8% in group B, 72.7% in group C and 71.4% in group D. Cross cerebellar diaschisis (CCD) was present in seven patients, and all of the primary cerebral perfusion defects of these patients were located at the territory of left or right middle cerebral artery. Conclusion: Cerebral perfusion SPECT is a potential tool to detect cerebral perfusion defects and CCD in patients with TIA. Although the perfusion defect may persist more than 5 days after onset, we suggest cerebral perfusion SPECT should be performed as soon as possible.

  6. Efeitos da fisioterapia respiratória na pressão intracraniana e pressão de perfusão cerebral no traumatismo cranioencefálico grave Effects of respiratory physiotherapy on intracranial pressure and cerebral perfusion pressure in severe traumatic brain injury patients

    Directory of Open Access Journals (Sweden)

    Cassia Toledo

    2008-12-01

    Full Text Available OBJETIVOS: Após um traumatismo cranioencefálico, a hipertensão intracraniana representa a maior causa de mortalidade, além da possibilidade de seqüelas funcionais, comportamentais e cognitivas. A escassez de estudos sobre os efeitos da fisioterapia respiratória nestes pacientes pode levar à condutas contraditórias. O objetivo deste estudo foi avaliar os efeitos de manobras usuais de fisioterapia respiratória sobre a pressão intracraniana e a pressão de perfusão cerebral em pacientes com traumatismo cranioencefálico grave. MÉTODOS: Ensaio clínico, prospectivo, em pacientes com traumatismo cranioencefálico, ventilados mecanicamente e com medida contínua da pressão intracraniana. Foram avaliados os efeitos das manobras de vibrocompressão manual e aspiração intratraqueal sem e com instilação de soro fisiológico, sobre as medidas de pressão intracraniana e de pressão de perfusão cerebral, entre o primeiro e o terceiro dia após a lesão cerebral. RESULTADOS: Foram obtidos os dados de 11 pacientes com idade de 41anos (mediana APACHE II de 19,5 ± 5. A manobra de vibrocompressão manual não determinou aumento da pressão intracraniana em nenhum dos dias avaliados. A pressão intracraniana aumentou significativamente após manobras de aspiração intratraqueal em relação à medida basal (dia 1, 9,5 ± 0,9 mm Hg vs 18,0 ± 3,2 mm Hg; dia 2, 10,6 ± 1,7 mm Hg vs 21,4 ± 3,8 mm Hg; dia 3, 14,4 ± 1,0 vs 24,9 ± 2,7 mm Hg; pOBJECTIVE: After brain injury intracranial hypertension is the major cause of mortality, in addition to the possibility of functional, behavioral and cognitive sequels. Scarcity of studies on the effects of respiratory physiotherapy on these patients may lead to contradictory performances. This study aimed to assess the effects of customary respiratory physiotherapy maneuvers on intracranial and cerebral perfusion pressures in patients with severe brain injury. METHODS: Clinical, prospective trial with

  7. Regional Cerebral Perfusion in Progressive Supranuclear Palsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Yong; Lee, Ki Hyeong; Yoon, Byung Woo; Lee, Sang Bok; Jeon, Beom S. [Samsung Medical Center, Seoul (Korea, Republic of); Lee, Kyung Han; Lee, Myung Chul [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1996-03-15

    Progressive supranuclear palsy (PSP) is a Parkinson-plus syndrome characterized clinically by supranuclear ophthalmoplegia, pseudobulbar palsy, axial rigidity, bradykinesia, postural instability and dementia. Presence of dementia and lack of cortical histopathology suggest the derangement of cortical function by pathological changes in subcortical structures in PSP, which is supported by the pattern of behavioral changes and measurement of brain metabolism using positron emission tomography. This study was done to examine whether there are specific changes of regional cerebral perfusion in PSP and whether there is a correlation between severity of motor abnormaility and degree of changes in cerebral perfusion. We measured regional cerebral perfusion indices in 5 cortical and 2 subcortical areas in 6 patients with a clinical diagnosis of PSP and 6 healthy age and sex matched controls using Tc-99m-HMPAO SPECT. Compared with age and sex matched controls, only superior frontal regional perfusion index was significantly decreased in PSP (p<0.05). There was no correlation between the severity of the motor abnormality and any of the regional cerebral perfusion indices (p>0.05). We affirm the previous reports that perfusion in superior frontal cortex is decreased in PSP. Based on our results that there was no correlation between severity of motor abnormality and cerebral perfusion in the superior frontal cortex, nonmotoric symptoms including dementia needs to be looked at whether there is a correlation with the perfusion abnormality in superior frontal cortex

  8. Personality factors correlate with regional cerebral perfusion.

    Science.gov (United States)

    O'Gorman, R L; Kumari, V; Williams, S C R; Zelaya, F O; Connor, S E J; Alsop, D C; Gray, J A

    2006-06-01

    There is an increasing body of evidence pointing to a neurobiological basis of personality. The purpose of this study was to investigate the biological bases of the major dimensions of Eysenck's and Cloninger's models of personality using a noninvasive magnetic resonance perfusion imaging technique in 30 young, healthy subjects. An unbiased voxel-based analysis was used to identify regions where the regional perfusion demonstrated significant correlation with any of the personality dimensions. Highly significant positive correlations emerged between extraversion and perfusion in the basal ganglia, thalamus, inferior frontal gyrus and cerebellum and between novelty seeking and perfusion in the cerebellum, cuneus and thalamus. Strong negative correlations emerged between psychoticism and perfusion in the basal ganglia and thalamus and between harm avoidance and perfusion in the cerebellar vermis, cuneus and inferior frontal gyrus. These observations suggest that personality traits are strongly associated with resting cerebral perfusion in a variety of cortical and subcortical regions and provide further evidence for the hypothesized neurobiological basis of personality. These results may also have important implications for functional neuroimaging studies, which typically rely on the modulation of cerebral hemodynamics for detection of task-induced activation since personality effects may influence the intersubject variability for both task-related activity and resting cerebral perfusion. This technique also offers a novel approach for the exploration of the neurobiological correlates of human personality.

  9. 重型颅脑外伤灌注CT结果与脑灌注压的相关性%Correlation of brain perfusion computed tomography results and cerebral perfusion pressure in patients with severe head trauma

    Institute of Scientific and Technical Information of China (English)

    徐裕; 冯东侠; 高恒; 那汉荣; 徐伟东; 周新民

    2012-01-01

    目的 探讨重型颅脑外伤患者灌注CF结果与脑灌注压监测结果的相关性.方法 50例重型颅脑外伤患者分为两组:T组28例,C组22例,人院时头颅CT平扫有明显异常.在行灌注CT时,同时监测平均动脉压(MAP)及颅内压(ICP),计算脑灌注压(CPP).应用直线回归分析灌注CT参数[局部脑血容量(rCBV)、局部脑血流(rCBF)和平均通过时间(MTT)]与CPP的相关性.结果 根据灌注CT结果,T组分为两个亚组:T1组,16例,灌注CT结果与CPP呈弱相关;T2组,12例,两者存在强相关.T1、T2和C组间的灌注CT参数均有明显差异.T1组的rCBF为(18.8±8.0)cm3·100g1·min-2,明显低于T2组的(60.2±21.3)cm3·100g1·min-1和C组的(48.3±11.0)CM3·100g1·min-1(P<0.01).T1、T2组灌注CT参数与相应CPP值之间均显著相关(P<0.01).结论 灌注CT结合ICP监测能提供有价值的评估脑血管自动调节功能是否完好的信息,有助于指导治疗.%Objective To investigate the correlation of brain perfusion computed tomography (CT) results and cerebral perfusion pressure (CPP) in patients with severe head trauma. Methods Perfusion CT results of 50 patients with head trauma were analyzed , who were divided into two groups of T(28 cases, severe head trauma with abnormal CT findings during admission) and C(22 cases,head trauma with normal CT findings during admission). The patients underwent perfusion CT and MAP and ICP were measured at the same time, by which CPP was calculated. The correlation between perfusion CT results [regional cerebral blood volume (rCBV), regional cerebral blood flow (rCBF) and MTT] and corresponding CPP was analyzed using linear regression analysis. Results According to perfusion CT results, group T was divided into two subgroups of Tl (16 cases, characterized by a weak correlation between the perfusion-CT results and the corresponding CPP values) and T2(12 cases,characterized by a strong correlation between the perfusion-CT results and the corresponding

  10. Ocular perfusion pressure in glaucoma.

    Science.gov (United States)

    Costa, Vital P; Harris, Alon; Anderson, Douglas; Stodtmeister, Richard; Cremasco, Fernanda; Kergoat, Helene; Lovasik, John; Stalmans, Ingborg; Zeitz, Oliver; Lanzl, Ines; Gugleta, Konstantin; Schmetterer, Leopold

    2014-06-01

    This review article discusses the relationship between ocular perfusion pressure and glaucoma, including its definition, factors that influence its calculation and epidemiological studies investigating the influence of ocular perfusion pressure on the prevalence, incidence and progression of glaucoma. We also list the possible mechanisms behind this association, and discuss whether it is secondary to changes in intraocular pressure, blood pressure or both. Finally, we describe the circadian variation of ocular perfusion pressure and the effects of systemic and topical medications on it. We believe that the balance between IOP and BP, influenced by the autoregulatory capacity of the eye, is part of what determines whether an individual will develop optic nerve damage. However, prospective, longitudinal studies are needed to better define the role of ocular perfusion pressure in the development and progression of glaucoma.

  11. Blood Pressure is Associated With Cerebral Blood Flow Alterations in Patients With T2DM as Revealed by Perfusion Functional MRI.

    Science.gov (United States)

    Xia, Wenqing; Rao, Hengyi; Spaeth, Andrea M; Huang, Rong; Tian, Sai; Cai, Rongrong; Sun, Jie; Wang, Shaohua

    2015-12-01

    Type 2 diabetes mellitus (T2DM) and hypertension are both associated with cognitive impairment and brain function abnormalities. We investigated whether abnormal cerebral blood flow (CBF) patterns exists in T2DM patients and possible relationships between aberrant CBF and cognitive performance. Furthermore, we examined the influence of hypertension on CBF alterations in T2DM patients. T2DM patients (n = 38) and non-T2DM subjects (n = 40) were recruited from clinics, hospitals, and normal community health screenings. Cerebral blood flow images were collected and analyzed using arterial spin labeling perfusion functional magnetic resonance imaging (fMRI). Regions with major CBF differences between T2DM patients and non-T2DM controls were detected via 1-way ANOVA. The interaction effects between hypertension and T2DM for CBF alterations were also examined. Correlation analyses illustrated the association between CBF values and cognitive performance and between CBF and blood pressure. Compared with non-T2DM controls, T2DM patients exhibited decreased CBF, primarily in the visual area and the default mode network (DMN); decreased CBF in these regions was correlated with cognitive performance. There was a significant interaction effect between hypertension and diabetes for CBF in the precuneus and the middle occipital gyrus. Additionally, blood pressure correlated negatively with CBF in T2DM patients.T2DM patients exhibited reduced CBF in the visual area and DMN. Hypertension may facilitate a CBF decrease in the setting of diabetes. T2DM patients may benefit from blood pressure control to maintain their brain perfusion through CBF preservation.

  12. Effects of Steroid Hormones on Sex Differences in Cerebral Perfusion.

    Science.gov (United States)

    Ghisleni, Carmen; Bollmann, Steffen; Biason-Lauber, Anna; Poil, Simon-Shlomo; Brandeis, Daniel; Martin, Ernst; Michels, Lars; Hersberger, Martin; Suckling, John; Klaver, Peter; O'Gorman, Ruth L

    2015-01-01

    Sex differences in the brain appear to play an important role in the prevalence and progression of various neuropsychiatric disorders, but to date little is known about the cerebral mechanisms underlying these differences. One widely reported finding is that women demonstrate higher cerebral perfusion than men, but the underlying cause of this difference in perfusion is not known. This study investigated the putative role of steroid hormones such as oestradiol, testosterone, and dehydroepiandrosterone sulphate (DHEAS) as underlying factors influencing cerebral perfusion. We acquired arterial spin labelling perfusion images of 36 healthy adult subjects (16 men, 20 women). Analyses on average whole brain perfusion levels included a multiple regression analysis to test for the relative impact of each hormone on the global perfusion. Additionally, voxel-based analyses were performed to investigate the sex difference in regional perfusion as well as the correlations between local perfusion and serum oestradiol, testosterone, and DHEAS concentrations. Our results replicated the known sex difference in perfusion, with women showing significantly higher global and regional perfusion. For the global perfusion, DHEAS was the only significant predictor amongst the steroid hormones, showing a strong negative correlation with cerebral perfusion. The voxel-based analyses revealed modest sex-dependent correlations between local perfusion and testosterone, in addition to a strong modulatory effect of DHEAS in cortical, subcortical, and cerebellar regions. We conclude that DHEAS in particular may play an important role as an underlying factor driving the difference in cerebral perfusion between men and women.

  13. Effects of Steroid Hormones on Sex Differences in Cerebral Perfusion.

    Directory of Open Access Journals (Sweden)

    Carmen Ghisleni

    Full Text Available Sex differences in the brain appear to play an important role in the prevalence and progression of various neuropsychiatric disorders, but to date little is known about the cerebral mechanisms underlying these differences. One widely reported finding is that women demonstrate higher cerebral perfusion than men, but the underlying cause of this difference in perfusion is not known. This study investigated the putative role of steroid hormones such as oestradiol, testosterone, and dehydroepiandrosterone sulphate (DHEAS as underlying factors influencing cerebral perfusion. We acquired arterial spin labelling perfusion images of 36 healthy adult subjects (16 men, 20 women. Analyses on average whole brain perfusion levels included a multiple regression analysis to test for the relative impact of each hormone on the global perfusion. Additionally, voxel-based analyses were performed to investigate the sex difference in regional perfusion as well as the correlations between local perfusion and serum oestradiol, testosterone, and DHEAS concentrations. Our results replicated the known sex difference in perfusion, with women showing significantly higher global and regional perfusion. For the global perfusion, DHEAS was the only significant predictor amongst the steroid hormones, showing a strong negative correlation with cerebral perfusion. The voxel-based analyses revealed modest sex-dependent correlations between local perfusion and testosterone, in addition to a strong modulatory effect of DHEAS in cortical, subcortical, and cerebellar regions. We conclude that DHEAS in particular may play an important role as an underlying factor driving the difference in cerebral perfusion between men and women.

  14. Transient influence of end-tidal carbon dioxide tension on the postural restraint in cerebral perfusion

    DEFF Research Database (Denmark)

    Immink, R.V.; Truijen, J.; Secher, Niels H.

    2009-01-01

    In the upright position, cerebral blood flow is reduced, maybe because arterial carbon dioxide partial pressure (Pa(CO(2))) decreases. We evaluated the time-dependent influence of a reduction in Pa(CO(2)), as indicated by the end-tidal Pco(2) tension (Pet(CO(2))), on cerebral perfusion during head......-up tilt. Mean arterial pressure, cardiac output, middle cerebral artery mean flow velocity (MCA V(mean)), and dynamic cerebral autoregulation at supine rest and 70 degrees head-up tilt were determined during free breathing and with Pet(CO(2)) clamped to the supine level. The postural changes in central...

  15. Hypertonic saline solution increases cerebral perfusion pressure during clinical orthotopic liver transplantation for fulminant hepatic failure: preliminary results Solução salina hipertônica aumenta a pressão de perfusão cerebral no transplante do fígado para hepatite fulminante: resultados preliminares

    Directory of Open Access Journals (Sweden)

    Joel Avancini Rocha Filho

    2006-06-01

    Full Text Available During orthotopic liver transplantation for fulminant hepatic failure, some patients may develop sudden deterioration of cerebral perfusion and oxygenation, mainly due to increased intracranial pressure and hypotension, which are likely responsible for postoperative neurological morbidity and mortality. In the present study, we hypothesized that the favorable effects of hypertonic saline solution (NaCl 7.5%, 4 mL/kg infusion on both systemic and cerebral hemodynamics, demonstrated in laboratory and clinical settings of intracranial hypertension and hemorrhagic shock resuscitation, may attenuate the decrease in cerebral perfusion pressure that often occurs during orthotopic liver transplantation for fulminant hepatic failure. METHODS: 10 patients with fulminant hepatic failure in grade IV encephalopathy undergoing orthotopic liver transplantation with intracranial pressure monitoring were included in this study. The effect on cerebral and systemic hemodynamics in 3 patients who received hypertonic saline solution during anhepatic phase (HSS group was examined, comparing their data with historical controls obtained from surgical procedure recordings in 7 patients (Control group. The maximal intracranial pressure and the corresponding mean arterial pressure values were collected in 4 time periods: (T1 the last 10 min of the dissection phase, (T2 the first 10 minutes at the beginning of anhepatic phase, (T3 at the end of the anhepatic phase, and (T4 the first 5 minutes after graft reperfusion. RESULTS: Immediately after hypertonic saline solution infusion, intracranial pressure decreased 50.4%. During the first 5 min of reperfusion, the intracranial pressure remained stable in the HSS group, and all these patients presented an intracranial pressure lower than 20 mm Hg, while in the Control group, the intracranial pressure increased 46.5% (P Neste estudo testamos a hipótese de que os efeitos benéficos decorrentes da administração da solu

  16. Magnetic resonance perfusion imaging evaluation in perfusion abnormalities of the cerebellum after supratentorial unilateral hyperacute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Pan Liang; Yunjun Yang; Weijian Chen; Yuxia Duan; Hongqing Wang; Xiaotong Wang

    2012-01-01

    Magnetic resonance imaging (MRI) data of 10 patients with hyperacute cerebral infarction (≤ 6 hours) were retrospectively analyzed. Six patients exhibited perfusion defects on negative enhancement integral maps, four patients exhibited perfusion differences in pseudo-color on mean time to enhance maps, and three patients exhibited perfusion differences in pseudo-color on time to minimum maps. Dynamic susceptibility contrast-enhanced perfusion weighted imaging revealed a significant increase in region negative enhancement integral in the affected hemisphere of patients with cerebral infarction. The results suggest that dynamic susceptibility contrast-enhanced perfusion weighted imaging can clearly detect perfusion abnormalities in the cerebellum after unilateral hyperacute cerebral infarction.

  17. Volume perfusion CT imaging of cerebral vasospasm: diagnostic performance of different perfusion maps

    Energy Technology Data Exchange (ETDEWEB)

    Othman, Ahmed E. [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Eberhard Karls University Tuebingen, University Hospital Tuebingen, Department for Diagnostic and Interventional Radiology, Tuebingen (Germany); Afat, Saif; Nikoubashman, Omid; Mueller, Marguerite; Wiesmann, Martin; Brockmann, Carolin [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Schubert, Gerrit Alexander [RWTH Aachen University, Department of Neurosurgery, Aachen (Germany); Bier, Georg [Eberhard Karls University Tuebingen, University Hospital Tuebingen, Department for Diagnostic and Interventional Neuroradiology, Tuebingen (Germany); Brockmann, Marc A. [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); University Hospital Mainz, Department of Neuroradiology, Mainz (Germany)

    2016-08-15

    In this study, we aimed to evaluate the diagnostic performance of different volume perfusion CT (VPCT) maps regarding the detection of cerebral vasospasm compared to angiographic findings. Forty-one datasets of 26 patients (57.5 ± 10.8 years, 18 F) with subarachnoid hemorrhage and suspected cerebral vasospasm, who underwent VPCT and angiography within 6 h, were included. Two neuroradiologists independently evaluated the presence and severity of vasospasm on perfusion maps on a 3-point Likert scale (0 - no vasospasm, 1 - vasospasm affecting <50 %, 2 - vasospasm affecting >50 % of vascular territory). A third neuroradiologist independently assessed angiography for the presence and severity of vasospasm on a 3-point Likert scale (0 - no vasospasm, 1 - vasospasm affecting < 50 %, 2 - vasospasm affecting > 50 % of vessel diameter). Perfusion maps of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to drain (TTD) were evaluated regarding diagnostic accuracy for cerebral vasospasm with angiography as reference standard. Correlation analysis of vasospasm severity on perfusion maps and angiographic images was performed. Furthermore, inter-reader agreement was assessed regarding findings on perfusion maps. Diagnostic accuracy for TTD and MTT was significantly higher than for all other perfusion maps (TTD, AUC = 0.832; MTT, AUC = 0.791; p < 0.001). TTD revealed higher sensitivity than MTT (p = 0.007). The severity of vasospasm on TTD maps showed significantly higher correlation levels with angiography than all other perfusion maps (p ≤ 0.048). Inter-reader agreement was (almost) perfect for all perfusion maps (kappa ≥ 0.927). The results of this study indicate that TTD maps have the highest sensitivity for the detection of cerebral vasospasm and highest correlation with angiography regarding the severity of vasospasm. (orig.)

  18. How to Perfuse: Concepts of Cerebral Protection during Arch Replacement

    Directory of Open Access Journals (Sweden)

    Andreas Habertheuer

    2015-01-01

    Full Text Available Arch surgery remains undoubtedly among the most technically and strategically challenging endeavors in cardiovascular surgery. Surgical interventions of thoracic aneurysms involving the aortic arch require complete circulatory arrest in deep hypothermia (DHCA or elaborate cerebral perfusion strategies with varying degrees of hypothermia to achieve satisfactory protection of the brain from ischemic insults, that is, unilateral/bilateral antegrade cerebral perfusion (ACP and retrograde cerebral perfusion (RCP. Despite sophisticated and increasingly individualized surgical approaches for complex aortic pathologies, there remains a lack of consensus regarding the optimal method of cerebral protection and circulatory management during the time of arch exclusion. Many recent studies argue in favor of ACP with various degrees of hypothermic arrest during arch reconstruction and its advantages have been widely demonstrated. In fact ACP with more moderate degrees of hypothermia represents a paradigm shift in the cardiac surgery community and is widely adopted as an emergent strategy; however, many centers continue to report good results using other perfusion strategies. Amidst this important discussion we review currently available surgical strategies of cerebral protection management and compare the results of recent European multicenter and single-center data.

  19. How to Perfuse: Concepts of Cerebral Protection during Arch Replacement

    Science.gov (United States)

    Habertheuer, Andreas; Wiedemann, Dominik; Kocher, Alfred; Laufer, Guenther; Vallabhajosyula, Prashanth

    2015-01-01

    Arch surgery remains undoubtedly among the most technically and strategically challenging endeavors in cardiovascular surgery. Surgical interventions of thoracic aneurysms involving the aortic arch require complete circulatory arrest in deep hypothermia (DHCA) or elaborate cerebral perfusion strategies with varying degrees of hypothermia to achieve satisfactory protection of the brain from ischemic insults, that is, unilateral/bilateral antegrade cerebral perfusion (ACP) and retrograde cerebral perfusion (RCP). Despite sophisticated and increasingly individualized surgical approaches for complex aortic pathologies, there remains a lack of consensus regarding the optimal method of cerebral protection and circulatory management during the time of arch exclusion. Many recent studies argue in favor of ACP with various degrees of hypothermic arrest during arch reconstruction and its advantages have been widely demonstrated. In fact ACP with more moderate degrees of hypothermia represents a paradigm shift in the cardiac surgery community and is widely adopted as an emergent strategy; however, many centers continue to report good results using other perfusion strategies. Amidst this important discussion we review currently available surgical strategies of cerebral protection management and compare the results of recent European multicenter and single-center data. PMID:26713319

  20. Diffusion and Perfusion MRI in Acute Cerebral Ischemia

    Institute of Scientific and Technical Information of China (English)

    Tchoyoson CC Lim; Chong-Tin Tan

    2001-01-01

    Reeent advances in magnetic resonance imaging (MRI), in particular diffusion weighted imaging (DWI) and perfusion weighted imaging (PWI), have allowed clinicians to have the ability to differentiate between irreversible cerebral infarction and the potentially reversible ischemic penumbra. This article examines the principles and practice of DWI and PWI. With continued advances in thrombolysis and other therapy for acute cerebral ischemia, neuroimaging is poised to play an increasingly important role in decisionmaking in aeute stroke.

  1. Arterial spin labeling perfusion MRI in cerebral ischaemia

    NARCIS (Netherlands)

    Bokkers, R.P.H.

    2011-01-01

    Cerebral perfusion is the basis for the delivery of oxygen and nutrients to the brain. Brain tissue can become damaged when there is a shortage in the blood supply. Basic physiological functions such as synaptic transmission, the membrane ion pump and energy metabolism are disrupted and within minut

  2. Changes in Cerebral Perfusion around the Time of Delayed Cerebral Ischemia in Subarachnoid Hemorrhage Patients

    NARCIS (Netherlands)

    Dankbaar, J. W.; de Rooij, N. K.; Smit, E. J.; Velthuis, B. K.; Frijns, C. J. M.; Rinkel, G. J. E.; van der Schaaf, I. C.

    2011-01-01

    Background: Because the pathogenesis of delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) is unclear, we studied cerebral perfusion at different time points around the occurrence of DCI. Methods: We prospectively enrolled 53 patients admitted to the University Medical Center Utrech

  3. Relationship between vasospasm, cerebral perfusion, and delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

    NARCIS (Netherlands)

    Dankbaar, Jan W.; Rijsdijk, Mienke; van der Schaaf, Irene C.; Velthuis, Birgitta K.; Wermer, Marieke J. H.; Rinkel, Gabriel J. E.

    2009-01-01

    Vasospasm after aneurysmal subarachnoid hemorrhage (SAH) is thought to cause ischemia. To evaluate the contribution of vasospasm to delayed cerebral ischemia (DCI), we investigated the effect of vasospasm on cerebral perfusion and the relationship of vasospasm with DCI. We studied 37 consecutive SAH

  4. Effect of anesthesia induction with muscle relaxant and opioid on intracranial pressure and cerebral perfusion pressure in patients with intracranial tumors%肌肉松弛剂和阿片类药物麻醉诱导对颅内肿瘤患者颅内压及脑灌注压的影响

    Institute of Scientific and Technical Information of China (English)

    胡玉红

    2012-01-01

    目的:探讨肌肉松弛剂和阿片类药物对颅内肿瘤患者颅内压和脑灌注压的影响.方法:选取2008-03~2011-03颅内肿瘤患者80例,随机分为2组.对照组使用常规麻醉,试验组使用肌肉松弛剂琥珀酰胆碱和阿片类药物芬太尼作诱导,再予常规麻醉,观察2组颅内压和脑灌注压的影响.结果:试验组术前、术中20 min、40 min、术毕后的颅内压、脑灌注压及术后苏醒时间与对照组相比均有显著差异(P<0.05).结论:在常规麻醉前使用肌肉松弛剂和阿片类药物进行诱导,能够有效降低麻醉中的颅内压,增加脑灌注压并缩短患者麻醉后苏醒时间.%Objective; To discuss the effect of anesthesia induction with muscle relaxant and opioid on intracranial pressure and cerebral perfusion pressure in patients with intracranial tumors. Methods: A total of 80 patients with intracranial tumors receiving surgical therapy from March 2008 to March 2011 were randomly divided into two groups: experimental group and control group. The patients in experimental group underwent anesthesia induction with muscle relaxant ( succinylcholine) and opioid (fentanyl) before conventional general anesthesia, and those in control group received conventional general anesthesia only. The intracranial pressure and cerebral perfusion pressure were observed for all patients. Results: Compared with control group, the intracranial pressure, cerebral perfusion pressure and postoperative analepsia time of patients in experimental group before operation, 20 and 40 min after starting of operation, and after finishing surgery were obviously different (P <0. 05). Conclusion:The anesthesia induction with muscle relaxant and opioid before conventional general anesthesia can decrease the intrao-perative intracranial pressure effectively, increase cerebral perfusion pressure and shorten postanesthesia analepsia time.

  5. Cerebral perfusion deficits in divers with neurological decompression illness

    Energy Technology Data Exchange (ETDEWEB)

    Wilmshurst, P.T.; O' Doherty, M.J.; Nunan, T.O. (Saint Thomas' Hospital, London (United Kingdom))

    1993-02-01

    Cerebral perfusion deficits detected by injection of [sup 99]Tc[sup m]-hexamethylpropyleneamine oxime (HMPAO) and single photon emission tomography is said to correlate well with clinical findings in divers with neurological decompression illness. We studied 12 divers. Six had residual cerebral signs (group 1) and six had no residual cerebral symptoms or signs (group 2). Perfusion deficits were as common in group 2 as in group 1. The site of the deficit did not correlate well with either the neurological findings at presentation or the residual clinical signs after treatment. The data suggest that claims that HMPAO scanning correlates with clinical findings and can be used for patient management were incorrect. (author).

  6. Personal computer aided cerebral perfusion imaging with dynamic CT

    Institute of Scientific and Technical Information of China (English)

    林燕; 高培毅

    2004-01-01

    @@Reports on the clinical implementation of dynamic computerised tomography (CT) perfusion imaging and quantitative measurement have increased dramatically of late.1-8 The advantages of dynamic CT perfusion imaging and quantitative measurement for the diagnosis of acute cerebral infarction have been acknowledged. However, most overseas CT vendors set perfusion imaging software package as an option for graphic workstation at a too high price for domestic practitioners. To foster the domestic implementation and development of this new technology, we have extended the earlier work.1,2 Applying the theory of central volume principle to DICOM 3.0 standard forms of prime CT images, we developed dynamic CT perfusion imaging and quantitative measure-ment programmes for PCs using Visual C+ + in Windows 98 system.

  7. Demonstration of cerebral perfusion abnormalities in moyamoya disease using susceptibility perfusion- and diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Adams, W.M.; Laitt, R.D. [Department of Neuroradiology, Central Manchester Healthcare Trust, Oxford Road, Manchester M13 9WL (United Kingdom); Li, K.L.; Jackson, A. [Department of Diagnostic Radiology, University of Manchester, Manchester M13 9PT (United Kingdom); Sherrington, C.R.; Talbot, P. [Department of Neurology, Central Manchester Healthcare Trust, Oxford Road, Manchester M13 9WL (United Kingdom)

    1999-02-01

    We describe the use of diffusion-weighted imaging and perfusion MRI using a contrast-medium bolus in the preoperative investigation for young man presenting with a cerebral ischaemic episode as a manifestation of moyamoya disease. (orig.) With 6 figs., 21 refs.

  8. PET imaging of cerebral perfusion and oxygen metabolism in stroke

    Energy Technology Data Exchange (ETDEWEB)

    Pointon, O.; Yasaka, M.; Berlangieri, S.U.; Newton, M.R.; Thomas, D.L.; Chan, C.G.; Egan, G.F.; Tochon-Danguy, H.J.; O``Keefe, G.; Donnan, G.A.; McKay, W.J. [Austin Hospital, Melbourne, VIC (Australia). Centre for PET and Depts of Nuclear Medicine and Neurology

    1998-03-01

    Full text: Stroke remains a devastating clinical event with few therapeutic options. In patients with acute stroke, we studied the cerebral perfusion and metabolic patterns with {sup 15}O-CO{sub 2} or H{sub 2}O and {sup 15}O-O{sub 2} positron emission tomography and correlated these findings to the clinical background. Forty three patients underwent 45 studies 0-23 days post-stroke (mean 7 days). Fifteen patients showed luxury perfusion (Group A), 10 had matched low perfusion and metabolism (B) and 3 showed mixed pattern including an area of misery perfusion (C). Seventeen showed no relevant abnormality (D) and there were no examples of isolated misery perfusion. Twelve of the 15 in Group A had either haemorrhagic transformation on CT, re-opening on angiography, or a cardioembolic mechanism. In contrast only 5/10 in Group B, 0/3 in Group C and 2/17 in Group D had these features. Although 7/10 in group B had moderate or large size infarcts on CT the incidence of haemorrhagic transformation was low (2/10) and significant carotid stenoses were more common in those studied (5/8) compared with the other groups. Misery perfusion was not seen beyond five days. Thus, luxury perfusion seems to be related to a cardio-embolic mechanism or reperfusion. Matched low perfusion and metabolism was associated with a low rate of haemorrhagic transformation despite a high incidence of moderate to large size infarcts. Misery perfusion is an early phenomenon in the evolution of ischaemic stroke.

  9. Retrograde cerebral perfusion (RCP) in aortic arch surgery: efficacy and possible mechanisms of brain protection.

    Science.gov (United States)

    Bavaria, J E; Pochettino, A

    1997-07-01

    Retrograde cerebral perfusion (RCP) was first introduced to treat air embolism during cardiopulmonary bypass (CPB). Its use was reintroduced to extend the safety of hypothermic circulatory arrest (HCA) during operations involving an open aortic arch. RCP seems to prevent cerebral rewarming during HCA. Both clinical and animal data suggest that RCP provides between 10% and 30% of baseline cerebral blood flow when administered through the superior vena cava (SVC) at jugular pressures of 20 to 25 mm Hg. RCP flows producing jugular venous pressures higher than 30 mm Hg may cause cerebral edema. Cerebral blood flow generated by RCP is able to sustain some cerebral metabolic activity, yet is not able to fully meet cerebral energy demands even at temperatures of 12 degrees to 18 degrees C. RCP may further prevent embolic events during aortic arch surgery when administered at moderate jugular vein pressures (RCP, when applied during aortic arch reconstruction, may extend the safe HCA period and improve morbidity and mortality, especially when HCA times are more than 60 minutes. RCP applied in patients and severe carotid and brachiocephalic occlusive disease may be ineffective, and caution is in order when RCP times are greater than 90 minutes.

  10. Method for performing cerebral perfusion-weighted MRI in neonates

    Energy Technology Data Exchange (ETDEWEB)

    Laswad, Tarek; Alamo, Leonor; Meuli, Reto; Gudinchet, Francois [University of Lausanne (CH). Radiology Department, Lausanne (Switzerland)]|[Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne (Switzerland); Wintermark, Pia; Moessinger, Adrien [University of Lausanne, Division of Neonatology, Lausanne (Switzerland)]|[Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne (Switzerland)

    2009-03-15

    Cerebral perfusion-weighted imaging (PWI) in neonates is known to be technically difficult and there are very few published studies on its use in preterm infants. In this paper, we describe one convenient method to perform PWI in neonates, a method only recently used in newborns. A device was used to manually inject gadolinium contrast material intravenously in an easy, quick and reproducible way. We studied 28 newborn infants, with various gestational ages and weights, including both normal infants and those suffering from different brain pathologies. A signal intensity-time curve was obtained for each infant, allowing us to build perfusion maps. This technique offered a fast and easy method to manually inject a bolus gadolinium contrast material, which is essential in performing PWI in neonates. Cerebral PWI is technically feasible and reproducible in neonates of various gestational age and with various pathologies. (orig.)

  11. [Ocular perfusion pressure and its relevance for glaucoma].

    Science.gov (United States)

    Schmidl, D; Werkmeister, R; Garhöfer, G; Schmetterer, L

    2015-02-01

    Ocular perfusion pressure is defined as the difference between arterial and venous pressure in ocular vessels. In practice, mean arterial pressure is used to substitute for arterial pressure in ocular vessels while intraocular pressure gives an estimate for ocular venous pressure. This results in a value that is easy to calculate and which is of importance since several studies have shown that it is correlated to the prevalence, incidence and progression of primary open angle glaucoma. Today, ocular perfusion pressure is used to estimate individual risks. Since no target value for ocular perfusion pressure can be defined, direct therapeutic intervention is difficult. Still, it has to be kept in mind that lowering intraocular pressure automatically leads to an increase in ocular perfusion pressure. The present article also points out problems and limitations in the concept of ocular perfusion pressure and suggests possible solutions for these problems in the future.

  12. The effects of propofol on cerebral perfusion MRI in children

    Energy Technology Data Exchange (ETDEWEB)

    Harreld, Julie H.; Helton, Kathleen J.; Reddick, Wilburn E.; Glass, John O.; Sansgiri, Rakhee; Ji, Qing; Patay, Zoltan [St. Jude Children' s Research Hospital, Department of Radiological Sciences, Memphis, TN (United States); Kaddoum, Roland N.; Parish, Mary Edna [St. Jude Children' s Research Hospital, Department of Anesthesiology, Memphis, TN (United States); Li, Yimei; Feng, Tianshu [St. Jude Children' s Research Hospital, Department of Biostatistics, Memphis, TN (United States); Gajjar, Amar [St. Jude Children' s Research Hospital, Department of Oncology, Memphis, TN (United States)

    2013-08-15

    The effects of anesthesia are infrequently considered when interpreting pediatric perfusion magnetic resonance imaging (MRI). The objectives of this study were to test for measurable differences in MR measures of cerebral blood flow (CBF) and cerebral blood volume (CBV) between non-sedated and propofol-sedated children, and to identify influential factors. Supratentorial cortical CBF and CBV measured by dynamic susceptibility contrast perfusion MRI in 37 children (1.8-18 years) treated for infratentorial brain tumors receiving propofol (IV, n = 19) or no sedation (NS, n = 18) were compared between groups and correlated with age, hematocrit (Hct), end-tidal CO{sub 2} (ETCO{sub 2}), dose, weight, and history of radiation therapy (RT). The model most predictive of CBF and CBV was identified by multiple linear regression. Anterior cerebral artery (ACA) and middle cerebral artery (MCA) territory CBF were significantly lower, and MCA territory CBV greater (p = 0.03), in IV than NS patients (p = 0.01, 0.04). The usual trend of decreasing CBF with age was reversed with propofol in ACA and MCA territories (r = 0.53, r = 0.47; p < 0.05). ACA and MCA CBF (r = 0.59, 0.49; p < 0.05) and CBV in ACA, MCA, and posterior cerebral artery territories (r = 0.73, 0.80, 0.52; p < 0.05) increased with weight in propofol-sedated children, with no significant additional influence from age, ETCO{sub 2}, hematocrit, or RT. In propofol-sedated children, usual age-related decreases in CBF were reversed, and increases in CBF and CBV were weight-dependent, not previously described. Weight-dependent increases in propofol clearance may diminish suppression of CBF and CBV. Prospective study is required to establish anesthetic-specific models of CBF and CBV in children. (orig.)

  13. 高血压脑出血无创颅内压及脑灌注压监测临床研究%Monitoring noninvasive intracranial pressure and cerebral perfusion pressure in treatment of patients with hypertensive intracerebral hemorrhage

    Institute of Scientific and Technical Information of China (English)

    张文德; 张湘; 邹志浩; 吴勤奋; 殷捷; 王建江; 郑玺; 莫拉丁

    2012-01-01

    Objective To evaluate clinical significance of monitoring noninvasive intracranial pressure (NICP) and cerebral perfusion pressure (CPP) in treatment of patients with hypertensive intracerebral hemorrhage. Methods This clinical randomized controlled trial enrolled 120 patients with hypertensive intracerebral hemorrhage who had sought medical treatment in our department from June 2008 through May 2010. They were randomized equally into a monitoring group where NICP and CPP were continuously monitored before and after operation and a non-monitoring group where no monitoring of NICP and CPP was performed. Results In the monitoring group,increased NICP and decreased CPP were shown in 50 patients and only 10 patients were shown with normal NICP (<26.6mmHg) and CPP (> 124.3 mm Hg). The abnormal NICP and CPP continuously monitored were treated with specific interventions like further operation or medication. In the non-monitoring group,patients received only conventional treatments.According to the Glasgow Outcome Scale (GOS), 31 patients (51.7%) had good recovery,20 (33.3%) were moderately disabled,5 (8.3%) severely disabled and 4 (6.7%) dead in the monitoring group while 23 (38.3%) patients had good recovery,18 (30.0%)were moderately disabled,10 (16.7%) severely disabled and 9 (15.0%) dead in the non-monitoring group.The outcomes of the monitoring group were significantly better than those of the non-monitoring group (P<0.05). Conclusion Continuous monitoring of NICP and CPP before and after operation should be performed in the treatment of patients with hypertensive intracerebral hemorrhage because it is helpful for clinical medication and reducing complications and mortality as well.%目的 探讨高血压脑出血手术前后监测无创颅内压(NICP)、脑灌注压(CPP)变化的临床意义. 方法 收集解放军第474医院神经外科自2008年6月至2010年5月收治的120例高血压脑出血手术患者,按照随机数字表法分为

  14. 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 cerebral...... metabolism (from arterial and internal jugular venous O(2), glucose and lactate differences), as well as the middle cerebral artery mean blood velocity (MCA V(mean); transcranial Doppler ultrasound) during a sustained static handgrip contraction at 40% of maximal voluntary contraction (n = 9) and the MCA V...... abolished by glycopyrrolate (P perfusion without affecting the cerebral metabolic rate for oxygen....

  15. Value of cerebral perfusion and vascular reserve for the treatment of symptomatic intracranial arterial stenosis

    Institute of Scientific and Technical Information of China (English)

    Li'an Huang; Xuewen Song; Anding Xu

    2008-01-01

    BACKGROUND: It is crucial to understand cerebral perfusion and vascular reserve in stegnotic arterial blood-supply regions to treat ischemic cerebrovascular diseases. However, effects on symptomatic intracrani-al arterial stenosis (SICAS) need to be further studied in additional applications. OBJECTIVE: To evaluate and summarize the effects of cerebral perfusion and vascular reserve on the treatment of SICAS. RETRIEVAL STRATEGY: A computer-based online search of English language publications from January 2000 to July 2007 was conducted in PubMed to identify publications that addressed cerebral perfusion and vascular reserve of SICAS. Search key words were "intracranial stenosis, perfusion, brain reserve". Relevant data were also searched with the China Journal Net, using the same key words in Chinese from January 2000 to January 2007. In total, 101 articles were retrieved. Inclusion criteria: ① Articles describing the current status for the diagnosis and treatment of SICAS; ② Articles concerning research developments of cerebral perfusion and vascular reserve of SICAS. Exclusion criteria: duplicated articles. LITERATURE EVALUATION: This study included 21 articles of experimental studies and conference re-ports.DATA SYNTHESIS: When performing interventional surgery in SICAS patients, it is important to under-stand cerebral perfusion and vascular reserve in addition to knowing the clinical symptoms and degrees of arterial stenosis. In recent years, there are a growing number of reports on measurements of vascular reserve through the use of magnetic resonance perfusion imaging (MR-PWI). Investigations demonstrate cerebral perfusion and vascular reserve decrease in many SICAS patients. Many studies show that both improve after surgical intervention. CONCLUSION: Cerebral perfusion could provide direct evidence of whether ischemia has occurred in the brain. Because of lateral circulation and cerebral vascular reserve, intracranial vascular stenosis and/or decreased

  16. Is misery perfusion still a predictor of stroke in symptomatic major cerebral artery disease?

    Science.gov (United States)

    Yamauchi, Hiroshi; Higashi, Tatsuya; Kagawa, Shinya; Nishii, Ryuichi; Kudo, Takashi; Sugimoto, Kanji; Okazawa, Hidehiko; Fukuyama, Hidenao

    2012-08-01

    Studies in the 1990s demonstrated that misery perfusion is a predictor of subsequent stroke in medically treated patients with symptomatic major cerebral artery disease. A recent randomized controlled trial demonstrated no benefit of bypass surgery for such patients. In this light, outcome in patients with misery perfusion has regained interest. The purpose of this study was to determine whether misery perfusion is still a predictor of subsequent stroke despite recent improvements in medical treatment for secondary prevention of stroke, and if so, whether the predictive value of misery perfusion has changed in recent years. We prospectively studied 165 non-disabled patients with symptomatic atherosclerotic internal carotid artery or middle cerebral artery occlusive diseases who underwent positron emission tomography from 1999 to 2008. Misery perfusion was defined as decreased cerebral blood flow, increased oxygen extraction fraction and decreased ratio of cerebral blood flow to blood volume in the hemisphere supplied by the diseased artery. All patients were followed up for 2 years until stroke recurrence or death. Bypass surgery was performed in 19 of 35 patients with and 16 of 130 patients without misery perfusion. The 2-year incidence of ipsilateral ischaemic stroke was six and four patients with and without misery perfusion, including two and one after surgery, respectively (P misery perfusion and 12 patients without (P misery perfusion in whole sample was 6.3 (95% confidence interval 1.7-22.4, P misery perfusion or bypass surgery did not differ. Between these periods, patients without misery perfusion demonstrated a decrease in stroke rate (from 16.2% to 0%), but patients with misery perfusion did not (26.3 and 25.0%). In symptomatic major cerebral artery disease, misery perfusion remains a predictor of subsequent stroke, although the recurrence rate was lower than the previous study. In patients without misery perfusion, the risk of stroke was reduced

  17. Prognostic indices for cerebral venous thrombosis on CT perfusion: A prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Rakesh Kumar, E-mail: rakrakgupta@gmail.com [Department of Radiodiagnosis and Imaging, MMIMSR, Mullana, Ambala (India); Bapuraj, J.R., E-mail: jrajiv@med.umich.edu [Department of Radiology, Division of Neuroradiology, University Hospital, University of Michigan, 1500 E Medical Center Drive, Ann Arbor, MI 48109 (United States); Khandelwal, N. [Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh (India); Khurana, Dheeraj [Department of Neurology, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh (India)

    2014-01-15

    Purpose: We determined the prognostic significance of CT perfusion characteristics of patients with cerebral venous sinus thrombosis (CVST) and assessed the change in perfusion parameters following anticoagulation therapy. Materials and methods: 20 patients with CVST diagnosed on non-contrast computed tomography (NCCT), magnetic resonance imaging (MRI), and magnetic resonance venography (MRV) were included in this study. The initial CT perfusion study was performed at the time of admission. The following perfusion parameters: relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), and relative mean transit time (rMTT) were calculated in the core and periphery of the affected area of the brain. Follow-up CT perfusion studies were performed at 1 month following anticoagulation therapy and the perfusion parameters thus obtained were compared with pre-treatment results. Receiver operating characteristic (ROC) curve analysis was performed to determine the prognostic significance of perfusion parameters. Results: All patients in this study showed areas of hypoperfusion on CT perfusion. To determine the favorable clinical outcome on basis of perfusion parameters, ROC curve analysis was performed which showed that the optimal threshold for rCBF > 60.5%, rCBV > 75.5%, and rMTT < 148.5% correlated with better clinical outcomes. Post treatment perfusion parameters showed significant correlation in core of the lesion (p < 0.05) than in the periphery. Conclusion: CT perfusion studies in CVST are a good prognostic tool and yield valuable information regarding clinical outcome.

  18. Maladaptation of cerebral perfusion in the spinal cord injured individuals

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Ihn Ho; Chun, Kyung A.; Lee, Hyoung Woo; Ahn, Sang Ho; Hayashida, Kohei [National Cardiovascular Center, Osaka (Korea, Republic of)

    2001-07-01

    The aim of this study was to evaluate the tilt-induced alteration of cerebral perfusion of spinal cord injured individuals. Supine and upright sitting brain SPECT was performed using a 1-day protocol with {sup 99m}Tc-ethylcysteinate dimer (ECD) in 11 SCI individuals (mean age, 32.6 y), with lesions between C3 and T4, ad 5 AB individuals (mean age, 31.4 y). The patients rested on a wheelchair in the supine position. Then, they sat up and, at the same time 555MBq of ECD was injected. The upright SPECT was done. Finally, 740MBq of ECD was injected and supine SPECT was performed again. The SPECT data were acquired with dual head gamma camera (E-cam, Siemens). For semiquantitative analysis, 14 ROIs were drawn on the brain. In the SCI individuals, the radiotracer uptake in the frontal, temporal and parietal areas were significantly decreased in the upright SPECT. No postural changes was evident in the occipital lobe, basal ganglia and thalamus in the SCI individuals. In the AB individuals, there were no such changes on the upright SPECT. Postural cerebral hypoperfusion in the frontal, temporal and parietal areas in the SCI individuals might relate to maladaptation of the vascular response during the upright position.

  19. Hypothermic Machine Perfusion of Kidney Grafts: Which Pressure is Preferred?

    NARCIS (Netherlands)

    B.M. Doorschodt; M.C.J.M. Schreinemachers; M. Behbahani; S. Florquin; J. Weis; M. Staat; R.H. Tolba

    2011-01-01

    To assess the effect of the perfusion pressure (PP) during machine perfusion (MP) on the preservation quality of kidney grafts, we compared mean PPs of 25 and 30 mmHg using a porcine autotransplantation model. After assessment of the microcirculation, animals underwent left nephrectomy. Thereafter,

  20. Effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies

    Science.gov (United States)

    Murase, Kenya; Nanjo, Takafumi; Satoshi, Ii; Miyazaki, Shohei; Hirata, Masaaki; Sugawara, Yoshifumi; Kudo, Masayuki; Sasaki, Kousuke; Mochizuki, Teruhito

    2005-11-01

    The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation × 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current.

  1. A study of cerebral perfusion using single photon emission computed tomography in neonates with brain lesions

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, J.; Contantinesco, A.; Brunot, B.; Messer, J. (Hospital Universitaire de Strasbourg (France))

    1994-03-01

    In this study the authors used a single photon emission computed tomography technique (SPECT) with radiolabelled [sup 99m]Tc HMPAO to assess cerebral perfusion in newborn infants with documented cerebral lesions and to determine to what extent brain SPECT might be useful in the neonatal period. A total of 15 newborn infants with the following cerebral pathologies were enrolled: severe parietal bilateral periventricular leucomalacia; moderate parietal bilateral PVL; intraventricular haemorrhage grade II with unilateral parietal parenchymal extension; cerebral infarction in the zone of middle cerebral artery; and post-haemorrhagic hydrocephalus. Follow-up was available in all infants. Alterations in cerebral perfusion were seen in only 12 of 15 infants and at the location of severe PVL, PE and CI. It was noted that the regions of diminished perfusion extended beyond the apparent extent of cerebral pathology delineated by ultrasound or magnetic resonance imaging. Markedly diminished perfusion was seen in one infant with hydrocephalus, which recovered following placement of ventriculo-peritoneal shunt. Regarding outcome, SPECT data failed to provide additional information than that of neuroradiological investigations. It is concluded that the use of SPECT, under these conditions, to assess alteration of cerebral perfusion in the neonatal period will not provide any additional information than that of neuroradiological investigations. 17 refs., 3 figs., 1 tab.

  2. The role of perfusion computed tomography in the prediction of cerebral hyperperfusion syndrome.

    Directory of Open Access Journals (Sweden)

    Chien Hung Chang

    Full Text Available BACKGROUND: Hyperperfusion syndrome (HPS following carotid angioplasty with stenting (CAS is associated with significant morbidity and mortality. At present, there are no reliable parameters to predict HPS. The aim of this study was to clarify whether perfusion computed tomography (CT is a feasible and reliable tool in predicting HPS after CAS. METHODOLOGY/PRINCIPAL FINDINGS: We performed a retrospective case-control study of 54 patients (11 HPS patients and 43 non-HPS with unilateral severe stenosis of the carotid artery who underwent CAS. We compared the prevalence of vascular risk factors and perfusion CT parameters including regional cerebral blood volume (rCBV, regional cerebral blood flow (rCBF, and time to peak (TTP within seven days prior to CAS. Demographic information, risk factors for atherosclerosis, and perfusion CT parameters were evaluated by multivariable logistic regression analysis. The rCBV index was calculated as [(ipsilateral rCBV - contralateral rCBV/contralateral rCBV], and indices of rCBF and TTP were similarly calculated. We found that eleven patients had HPS, including five with intracranial hemorrhages (ICHs of whom three died. After a comparison with non-HPS control subjects, independent predictors of HPS included the severity of ipsilateral carotid artery stenosis, 3-hour mean systolic blood pressure (3 h SBP after CAS, pre-stenting rCBV index >0.15 and TTP index >0.22. CONCLUSIONS/SIGNIFICANCE: The combination of severe ipsilateral carotid stenosis, 3 h SBP after CAS, rCBV index and TTP index provides a potential screening tool for predicting HPS in patients with unilateral carotid stenosis receiving CAS. In addition, adequate management of post-stenting blood pressure is the most important treatable factor in preventing HPS in these high risk patients.

  3. 脑血流有效灌注压的无创检测及其对急性脑梗死的临床意义%The Effective Cerebral Blood Flow Perfusion Pressure Noninvasive Monitoring and Its Relationship with the Clinical Signiifcance of Acute Cerebral Infarction

    Institute of Scientific and Technical Information of China (English)

    梁兵; 袁芳; 梁云云; 傅贤; 解龙昌; 殷建瑞; 高庆春

    2014-01-01

    通过TCD无创检测并计算CPPe的新方法可以获得较为准确的CPPe,而且CPPe与急性脑梗死患者的颈内动脉狭窄程度密切相关,这使得CPPe可能可以为脑血管病患者无创脑血流检测、指导个体化血压调控提供可靠证据。%Objective To explore the effectiveness of noninvasive detection method of the effective cerebral perfusion pressure (CPPe) and the relationship between the CPPe and the internal carotid artery (ICA) stenosis in patients with acute cerebral infarction. Methods For the prospective study, this study collected 41 cases patients with acute cerebral infarction within 1 week in the Second Affiliated Hospital of Guangzhou University from January 2010 to January 2012. We used digital subtraction angiography (DSA) and transcranial Doppler ultrasonography (TCD) to prospectively detect the internal carotid artery stenosis degree, noninvasive blood pressure, invasive blood pressure and cerebral artery blood flow velocity of 41 patients. After calculating CPPe according to tested results, we compared the speciifcity and accuracy of invasive and noninvasive CPPe in all of the patients with acute cerebral infarction. At the same time according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) standard, all of the patients with acute cerebral infarction were divided into mild stenosis group, moderate stenosis group and severe stenosis group. And we also compared vascular risk factors, CPPe and National Institutes of Health Stroke Scale (NIHSS) score among three groups, and analyzed the correlation between CPPe, NIHSS score and intracranial artery stenosis degree. Results Compare all of the patients with acute cerebral infarction of invasive and noninvasive CPPe, the results showed that the invasive CPPe had a median of 56.6 mmHg, the noninvasive CPPe had a median of 57.8 mmHg, and there was no significant difference between the two evaluation methods by TCD and DSA. The invasive CPPe of

  4. Comparison of Cerebral Oxygen Saturation and Cerebral Perfusion Computed Tomography in Cerebral Blood Flow in Patients with Brain Injury.

    Science.gov (United States)

    Trofimov, Alexey O; Kalentiev, George; Voennov, Oleg; Grigoryeva, Vera

    2016-01-01

    The purpose of this study was to determine the relationship between cerebral tissue oxygen saturation and cerebral blood volume in patients with traumatic brain injury. Perfusion computed tomography of the brain was performed in 25 patients with traumatic brain injury together with simultaneous SctO2 level measurement using cerebral near-infrared oxymetry. The mean age of the injured persons was 34.5±15.6 years (range 15-65); 14 men, 11 women. The Injury Severity Score (ISS) values were 44.4±9.7 (range 25-81). The Glasgow Coma Score (GCS) mean value before the study was 10.6±2.1 (range 5-13). SctO2 ranged from 51 to 89%, mean 62±8.2%. Cerebral blood volume (CBV) values were 2.1±0.67 ml/100 g (min 1.1; max 4.3 ml/100 g). Cerebral blood flow (CBF) was 31.99±13.6 ml/100 g×min. Mean transit time (MTT) values were 5.7±4.5 s (min 2.8; max 34.3 s). The time to peak (TTP) was 22.2±3.1 s. A statistically significant correlation was found between SctO2 level and cerebral blood volume (CBV) level (R=0.9; pperfusion.

  5. Helical CT study of cerebral perfusion and related hemodynamic parameters

    Science.gov (United States)

    Cenic, Aleksa; Lee, Ting-Yim; Craen, Rosemary A.; Gelb, Adrian W.

    1997-05-01

    A convenient method for assessing cerebral perfusion and related functional parameters has been developed using a third generation slip-ring CT scanner. Dynamic contrast- enhanced scanning at the same level was employed to image the cerebral circulation at the rate of 1 image per second. Using data acquired with this non-helical mode of scanning, we have developed a method for the simultaneous in-vivo determination of cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT). These measurements are given in the same physiological units as positron emission tomography. In order to obtain accurate measurements of these parameters, methods were also developed to correct for recirculation and partial volume averaging in imaging small blood vessels. We have used 6 New Zealand white rabbits in our studies. For each rabbit, up to 3 CT measurements of CBF, CBV, and MTT were made at normocapnia under isoflurane anesthesia. Coronal sections through the brain were imaged while simultaneously imaging either a brain artery or the ear artery. Images were acquired for 1 minute as Isovue 300 was injected intravenously. In the acquired CT images, regions of interest in brain parenchyma and an artery were drawn. For each region of interest, the mean CT number in pre-contrast images was subtracted from the mean in post-contrast images to calculate the contrast concentration curves for the brain regions Q(t) and the arterial region Ca(t). Using a robust deconvolution method, the MTT was determined. CBV was then determined from the ratio of the areas of Q(t) and Ca(t). Finally, CBF was calculated from the Central Volume Principle. The mean regional CBF, CBV and MTT values were 73.3 +/- 5.1 ml/min/100g, 1.93 +/- 0.12 ml/100g and 1.80 +/- 0.18 s respectively. IN order to validate our CT CBF measurements, we also measured CBF using the well- established technique of microspheres with each CT study. The feasibility of our CT method to measure CBF accurately was

  6. Aortic outflow cannula tip design and orientation impacts cerebral perfusion during pediatric cardiopulmonary bypass procedures.

    Science.gov (United States)

    Menon, Prahlad G; Antaki, James F; Undar, Akif; Pekkan, Kerem

    2013-12-01

    Poor perfusion of the aortic arch is a suspected cause for peri- and post-operative neurological complications associated with cardiopulmonary bypass (CPB). High-speed jets from 8 to 10FR pediatric/neonatal cannulae delivering ~1 L/min of blood can accrue sub-lethal hemolytic damage while also subjecting the aorta to non-physiologic flow conditions that compromise cerebral perfusion. Therefore, we emphasize the importance of cannulation strategy and hypothesize engineering better CPB perfusion through a redesigned aortic cannula tip. This study employs computational fluid dynamics to investigate novel diffuser-tipped aortic cannulae for shape sensitivity to cerebral perfusion, in an in silico cross-clamped aortic arch model modeled with fixed outflow resistances. 17 parametrically altered configurations of an 8FR end-hole and several diffuser cone angled tips in combination with jet incidence angles toward or away from the head-neck vessels were studied. Experimental pressure-flow characterizations were also conducted on these cannula tip designs. An 8FR end-hole aortic cannula delivering 1 L/min along the transverse aortic arch was found to give rise to backflow from the brachicephalic artery (BCA), irrespective of angular orientation, for the chosen ascending aortic insertion location. Parametric alteration of the cannula tip to include a diffuser cone angle (tested up to 7°) eliminated BCA backflow for any tested angle of jet incidence. Experiments revealed that a 1 cm long 10° diffuser cone tip demonstrated the best pressure-flow performance improvement in contrast with either an end-hole tip or diffuser cone angles greater than 10°. Performance further improved when the diffuser was preceded by an expanded four-lobe swirl inducer attachment-a novel component. In conclusion, aortic cannula orientation is crucial in determining net head-neck perfusion but precise angulations and insertion-depths are difficult to achieve practically. Altering the cannula tip

  7. Perfusion-CT for early assessment of traumatic cerebral contusions

    Energy Technology Data Exchange (ETDEWEB)

    Soustiel, Jean F.; Mahamid, Eugenia; Goldsher, Dorith; Zaaroor, Menashe [Faculty of Medicine, Technion - Israel Institute of Technology, Department of Neurosurgery, Rambam Medical Center, P.O. Box 9602, Haifa (Israel)

    2008-02-15

    To investigate the value of perfusion-CT (PCT) for assessment of traumatic cerebral contusions (TCC) and to compare the abilities of early noncontrast CT and PCT modalities to evaluate tissue viability. PCT studies performed in 30 patients suffering from TCC during the acute phase of their illness were retrospectively reviewed. Cerebral blood flow (CBF), volume (CBV) and mean transit time (MTT) were measured in three different areas: the hemorrhagic core of the TCC, the surrounding hypodense area and the perilesional normal-appearing parenchyma. TCC area was measured on CBF-, CBV- and MTT-derived maps and compared with the areas measured using the same slice obtained with CT scans performed on admission, at the time of PCT (follow-up CT) and at 1 week. TCC were characterized by low CBF and CBV values (9.2{+-}6.6 ml/100 g per min and 0.9{+-}0.7 ml/100 g, respectively) and a significant prolongation of MTT (11.9{+-}10.7 s) in the hemorrhagic core whereas PCT parameters were more variable in the hypodense area. The TCC whole area showed a noticeable growth of the lesions during the first week of admission. In comparison with early noncontrast CT, CBV and CBF maps proved to be more congruent with the findings of noncontrast CT scans at 1 week. PCT confirmed the results of xenon-CT studies and was shown to allow better evaluation of tissue viability than noncontrast CT. These findings suggest that PCT could be implemented in the future for the early assessment of patients with traumatic brain injury. (orig.)

  8. Imaging findings and cerebral perfusion in arterial ischemic stroke due to transient cerebral arteriopathy in children; Achados de imagem e perfusao arterial cerebral em acidente vascular cerebral isquemico devido a arteriopatia transitoria em crianca

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa Junior, Alcino Alves, E-mail: alcinojr@uol.com.br [Departamento de Diagnostico por Imagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Ellovitch, Saada Resende de Souza [Neuropediatria, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Pincerato, Rita de Cassia Maciel [Hospital Samaritano, Sao Paulo, SP (Brazil)

    2012-04-15

    We report the case of a 4-year-old female child who developed an arterial ischemic stroke in the left middle cerebral artery territory, due to a proximal stenosis of the supraclinoid internal carotid artery, most probably related to transient cerebral arteriopathy of childhood. Computed tomography scan, magnetic resonance imaging, perfusion magnetic resonance and magnetic resonance angiography are presented, as well as follow-up by magnetic resonance and magnetic resonance angiography exams. Changes in cerebral perfusion and diffusion-perfusion mismatch call attention. As far as we know, this is the first report of magnetic resonance perfusion findings in transient cerebral arteriopathy. (author)

  9. Predicting hemorrhagic transformation by microvascular permeability using perfusion CT acute cerebral infarction in elderly patients

    Institute of Scientific and Technical Information of China (English)

    田超

    2014-01-01

    Objective To study the possibility of microvascular permeability(PS)value derived from perfusion CT(PCT)in predicting hemorrhagic transformation(HT)in acute cerebral infarction in elderly patients.Methods 52consecutive patients with middle cerebral artery acute ischemic stroke who received thrombolytic therapy were divided into HT group and control group,and patients in

  10. Effect of propofol and remifentanil on cerebral perfusion and oxygenation in pigs

    DEFF Research Database (Denmark)

    Mikkelsen, Mai Louise Grandsgaard; Ambrus, Rikard; Miles, James Edward;

    2016-01-01

    The objective of this review is to evaluate the existing literature with regard to the influence of propofol and remifentanil total intravenous anaesthesia (TIVA) on cerebral perfusion and oxygenation in healthy pigs. Anaesthesia has influence on cerebral haemodynamics and it is important not onl...

  11. Transient influence of end-tidal carbon dioxide tension on the postural restraint in cerebral perfusion

    NARCIS (Netherlands)

    R.V. Immink; J. Truijen; N.H. Secher; J.J. van Lieshout

    2009-01-01

    Immink RV, Truijen J, Secher NH, Van Lieshout JJ. Transient influence of end-tidal carbon dioxide tension on the postural restraint in cerebral perfusion. J Appl Physiol 107: 816-823, 2009. First published July 2, 2009; doi: 10.1152/japplphysiol.91198.2008.-In the upright position, cerebral blood fl

  12. Cerebral perfusion changes in traumatic diffuse brain injury. IMP SPECT studies

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hiroshi; Kawashima, Ryuta; Fukuda, Hiroshi [Tohoku Univ., Sendai (Japan). Inst. of Development, Aging and Cancer; Ishii, Kiyoshi; Onuma, Takehide

    1997-05-01

    Diffuse brain injury (DBI) is characterized by axonal degeneration and neuronal damage which cause diffuse brain atrophy. We have investigated the time course of abnormalities in cerebral perfusion distribution in cases of DBI by using Iodine-123-IMP SPECT, and the relationship to the appearance of diffuse brain atrophy. SPECT scans were performed on eight patients with diffuse brain injury due to closed cranial trauma in acute and chronic stages. All patients showed abnormalities in cerebral perfusion with decreases in perfusion, even in non-depicted regions on MRI, and the affected areas varied throughout the period of observation. Diffuse brain atrophy appeared in all patients. In some patients, diffuse brain atrophy was observed at or just after the time when the maximum number of lesions on SPECT were seen. The abnormalities in cerebral perfusion in cases of DBI might therefore be related to axonal degeneration and neuronal damage which causes diffuse brain atrophy. (author)

  13. Endotoxemia reduces cerebral perfusion but enhances dynamic cerebrovascular autoregulation at reduced arterial carbon dioxide tension*

    DEFF Research Database (Denmark)

    Brassard, Patrice; Kim, Yu-Sok; van Lieshout, Johannes

    2012-01-01

    OBJECTIVE:: The administration of endotoxin to healthy humans reduces cerebral blood flow but its influence on dynamic cerebral autoregulation remains unknown. We considered that a reduction in arterial carbon dioxide tension would attenuate cerebral perfusion and improve dynamic cerebral......-104] mm Hg; p = .75), but increased cardiac output (8.3 [6.1-9.5] L·min vs. 6.0 [4.5-8.2] L·min; p = .02) through an elevation in heart rate (82 ± 9 beats·min vs. 63 ± 10 beats·min; p arterial carbon dioxide tension (37 ± 5 mm Hg vs. 41 ± 2 mm Hg; p artery mean...... in arterial carbon dioxide tension explains the improved dynamic cerebral autoregulation and the reduced cerebral perfusion encountered in healthy subjects during endotoxemia....

  14. 轻度过度通气对幕上占位开颅患者麻醉后颅内压、脑灌注压以及血流动力学影响%The influence of mild hyperventilation to intracranial pressure,cerebral perfusion pressure and hemodynamics during supratentorial craniotomy

    Institute of Scientific and Technical Information of China (English)

    陈一丁; 张宏伟; 唐育民; 张兆辉; 罗江辉

    2011-01-01

    Objective To observe the influence of mild hyperventilation to intracranial pressure (ICP) 、cerebral perfusion pressure (CPP) and hemodynamic during supratentorial craniotomy, and to provide evidence for applicable neurosurgical anesthesiology. Methods 21 patients with supratentorial tumor were given mild hyperventilation, with EtCO2 30 ~ 35mmHg and peak airway pressure 10 ~18cmH2O. The ICP through lumbar cerebrospinal fluid pressure, the central venous pressure (CVP) in superior vena cava, the intra-abdominal pressure (IAP) through intra-bladder pressure (IBP), the mean arterial pressure (MAP)by peripheral arterial cannulation, and CPP were analyzed during the period from anesthesia induction to opening the hard meninges. Results The mild hyperventilation significantly increased the CVP、IBP and ICP, while significantly decreased the MAP and CPP in patients under anesthesia. Conclusion It's essential to remove skull bone flap to decrease ICP as soon as possible after anesthesia and positive ventilation, to prevent the abrupt decreasing of CPP. The mild hyperventilation doesn't provide beneficial effects to cerebral perfusion, and further comparative study for ventilation strategy should be designed.%目的 观察轻度过度通气对幕上占住开颅患者麻醉后颅内压、脑灌注压以及血流动力学的影响.为临床上合理的神经外科麻醉方法提供依据.方法 对21例幕上占位开颅患者给予轻度过度通气,控制呼吸末CO 30~35mmHg和气道峰压10~18cmHO,在全麻诱导前至开硬脑膜后这一时间段,分析经腰段脑脊液监测颅内压、经上腔静脉监测中心静脉压、经膀胱监测腹腔压、经有创动脉监测平均动脉压以及脑灌注压变化.结果 轻度过度通气显著增高了全麻后患者中心静脉压,膀胱压和颅内压,降低了平均动脉压和脑灌注压.结论 麻醉正压通气后应尽快开颅减压,降低颅内压,避免脑灌注压过度下降.轻度过度通气

  15. Cerebral hemodynamics after short- and long-term reduction in blood pressure in mild and moderate hypertension.

    NARCIS (Netherlands)

    Zhang, R.; Witkowski, S.; Fu, Q.; Claassen, J.A.H.R.; Levine, B.D.

    2007-01-01

    This study tested the hypothesis that acute reduction in blood pressure (BP) at the initial stage of antihypertensive therapy compromises brain perfusion and dynamic cerebral autoregulation in patients with hypertension. Cerebral blood flow velocity and BP were measured in patients with mild and mod

  16. A study on cerebral hemodynamic analysis of moyamoya disease by using perfusion MRI

    Science.gov (United States)

    Dong, Kyung-Rae; Goo, Eun-Hoe; Lee, Jae-Seung; Chung, Woon-Kwan

    2013-10-01

    This study examined the clinical applications of perfusion magnetic resonance imaging (MRI) in patients with moyamoya disease (MMD). Twenty-two patients with moyamoya disease (9 men and 13 women) with a mean age of 9.3 years (range: 4-22 years) were enrolled in this study. Perfusion MRI was performed by scanning the patients7.5 cm upward from the base of the cerebellum before their being process for post-treatment. The scan led to the acquisition of the following four map images: the cerebral blood volume (CBV), the cerebral blood flow (CBF), the mean transit time (MTT) for the contrast medium, and the time to peak (TTP) for the contrast medium. The lesions were assessed using the CBV, the CBF, the MTT and the TTP maps of perfusion MRI; the MTT and the TTP were measured in the lesion areas, as well as in the normal and the symmetric areas. Perfusion defects were recognizable in all four perfusion MRI maps, and the MTT and the TTP showed a conspicuous delay in the parts where perfusion defects were recognized. The MTT and the TTP images of perfusion MRI reflected a significant correlation between the degrees of stenosis and occlusion in the posterior cerebral artery (PCA), as well as the development of collateral vessels. The four perfusion MRI maps could be used to predict the degrees of stenosis and occlusion in the posterior circulation, as well as the development of the collateral vessels, which enabled a hemodynamic evaluation of the parts with perfusion defects. Overall, perfusion MRI is useful for the diagnosis and the treatment of moyamoya disease and can be applied to clinical practice.

  17. Perfusion pressure flow study in the upper urinary tract

    Directory of Open Access Journals (Sweden)

    Hong-Lin Cheng

    2015-06-01

    Full Text Available Hydronephrosis with an undetermined pathology is a common condition detected in imaging studies. In urological clinical practice, it is a persistent dilemma to predict whether this condition will progress to result in the deterioration of renal function. Perfusion pressure flow study of the upper urinary tract, known as the Whitaker test, provides an alternative diagnostic tool for solving this condition. Perfusion pressure flow study has been criticized for its invasiveness, nonphysiological approach, and inconsistency in predicting outcomes. However, it continues to be used to evaluate difficult or equivocal cases and to provide an objective assessment of the upper urinary tract.

  18. Evaluation of multislice computed tomographic perfusion imaging and computed tomographic angiography on traumatic cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    XU Fang-hong; CHEN Wei-jian; YANG Yun-jun; DUAN Yu-xia; FU Feng-li

    2008-01-01

    Objective: To evaluate the application value of multislice computed tomographic perfusion imaging (MSCTPI) and multislice computed tomographic angiography (MSCTA) on traumatic cerebral infarction. Methods: MSCTA was performed on 10 patients who were initiailly diagnosed as traumatic cerebral infarction by normal conventional computed tomography (NCCT), among whom, 3 patients were examined by MSCTPI simultaneously. Reconstructed images of the intracranial artery were made with techniques of maximum intensity projection (MIP) and volume rendering (VR) from MSCTA scanning data. Then the graph of function of four parameters, regional cerebral blood flow (Rcbf), regional cerebral blood volume (Rcbv), mean transit time (MTT), and time to peak (TTP), acquired by the perfusing analysis software was obtained. Results: Among the 10 patients with traumatic cerebral infarction, 6 showed complex type on NCCT, which depicted abnormality on MSCTA, and 4 showed simple type on NCCT, which had negative results on MSCTA. Among the 4 patients with abnormal great vessels, 2 suffered from steno sis or occlusion of the middle cerebral artery, 1 from spasm of the anterior cerebral artery, and 1 from spasm of the vertebral-basal artery. The image of MSCTPI of 1 patient with massive cerebral infarction on the right cerebral hemisphere confirmed by CT was smaller than those of the other patients, which showed occlusion of the ipsilateral middle cerebral artery on MSCTA. Among the 6 patients whose MSCTA showed no abnormality, 4 showed simple infarction and 2 showed complex infarction. The infarction focus of 5 patients occurred in the basal ganglia and 1 in the splenium of corpus callosum. Among the 2 cases of small cerebral infarction volume on NCCT, one was normal, the other showed hypoperfusion on MSCTPI and was normal on MSCTA. Conclusion: The combination of MSCTPI and MSCTA is very useful for evaluating the change of intracranial artery in ischemic regions and assessing the cerebral

  19. Effect of isovolemic, isothermic hemodialysis on cerebral perfusion and vascular stiffness using contrast computed tomography and pulse wave velocity.

    Directory of Open Access Journals (Sweden)

    Ansgar Reising

    Full Text Available BACKGROUND: Patients undergoing hemodialysis treatment have a six-fold increased risk for stroke relative to the general population. However, the effect of hemodialysis on cerebral blood flow is poorly studied and confounding factors like blood pressure and ultrafiltration as well as temperature changes have rarely been accounted for. The aim of our study was to use state-of-the-art technology to evaluate the effect of a single dialysis session on cerebral perfusion as well as on vascular stiffness. METHODS: Chronic hemodialysis patients (7 male/3 female, mean age 58 years were recruited. Cerebral blood flow and arterial pulse wave velocity were measured before and immediately after a hemodialysis session. To exclude effects of volume changes we kept ultrafiltration to a minimum, allowing no change in body weight. Isothermic conditions were maintained by using the GENIUS single-pass batch-dialysis system with a high-flux polysulfone dialyser. Cerebral blood flow was measured by contrast-enhanced computed tomography. Pulse wave velocity was measured using the SphygmoCor (AtCor Medical, USA device by a single operator. RESULTS: This study shows for the first time that isovolemic, isothermic hemodialysis neither affected blood pressure or heart rate, nor total or regional cerebral perfusion. There was also no change in pulse wave velocity. CONCLUSIONS: Mechanisms other than the dialysis procedure itself might be causative for the high incidence of ischemic strokes in this patient population. Moreover, the sole removal of uremic toxins does not lead to short-term effects on vascular stiffness, underlying the importance of volume control in this patient population.

  20. Dependency of cerebral blood flow upon mean arterial pressure in patients with acute bacterial meningitis

    DEFF Research Database (Denmark)

    Møller, Kirsten; Larsen, Fin Stolze; Qvist, Jesper;

    2000-01-01

    OBJECTIVE: Patients with acute bacterial meningitis are often treated with sympathomimetics to maintain an adequate mean arterial pressure (MAP). We studied the influence of such therapy on cerebral blood flow (CBF). DESIGN: Prospective physiologic trial. SETTING: The Department of Infectious...... Diseases, Copenhagen University Hospital, Denmark. PATIENTS: Sixteen adult patients with acute bacterial meningitis. INTERVENTION: Infusion of norepinephrine to increase MAP. MEASUREMENTS: During a rise in MAP induced by norepinephrine infusion, we measured relative changes in CBF by transcranial Doppler...... bacterial meningitis, CBF autoregulation is impaired. With recovery from meningitis, the cerebral vasculature regains the ability to maintain cerebral perfusion at a constant level despite variations in MAP....

  1. Validation and absolute quantification of MR perfusion compared with CT perfusion in patients with unilateral cerebral arterial stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, Fang-Ying, E-mail: fychiou@hotmail.com [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China); Kao, Yi-Hsuan, E-mail: yhkao@ym.edu.tw [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China); Teng, Michael Mu Huo, E-mail: mhteng@gmail.com [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China); School of Medicine, National Yang-Ming University, Taipei City, Taiwan (China); Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan (China); Chung, Hsiao-Wen, E-mail: chung@cc.ee.ntu.edu.tw [Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan (China); Chang, Feng-Chi, E-mail: fcchang374@gmail.com [School of Medicine, National Yang-Ming University, Taipei City, Taiwan (China); Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan (China); Cho, I-Chieh, E-mail: jessie8030@yahoo.com.tw [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China); Chen, Wen-Chun, E-mail: sky7408695@hotmail.com [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei City, Taiwan (China)

    2012-12-15

    Objective: The aim of the study was to assess absolute quantification of dynamic susceptibility contrast-enhanced magnetic resonance perfusion (MRP) comparing with computed tomography perfusion (CTP) in patients with unilateral stenosis. Materials and methods: We retrospectively post-processed MRP in 20 patients with unilateral occlusion or stenosis of >79% at the internal carotid artery or the middle cerebral artery (MCA). Absolute quantification of MRP was performed after applying the following techniques: cerebrospinal fluid removal, vessel removal, and automatic segmentation of brain to calculate the scaling factors to convert relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) values to absolute values. For comparison between MRP and CTP, we manually deposited regions of interest in bilateral MCA territories at the level containing the body of the lateral ventricle. Results: The correlation between MRP and CTP was best for mean transit time (MTT) (r = 0.83), followed by cerebral blood flow (CBF) (r = 0.52) and cerebral blood volume (CBV) (r = 0.43). There was no significant difference between CTP and MRP for CBV, CBF, and MTT on the lesion side, the contralateral side, the lesion-contralateral differences, or the lesion-to-contralateral ratios (P > 0.05). The mean differences between MRP and CTP were as follows: CBV −0.57 mL/100 g, CBF 2.50 mL/100 g/min, and MTT −0.90 s. Conclusion: Absolute quantification of MRP is possible. Using the proposed method, measured values of MRP and CTP had acceptable linear correlation and quantitative agreement.

  2. A pattern of cerebral perfusion anomalies between Major Depressive Disorder and Hashimoto Thyroiditis

    Directory of Open Access Journals (Sweden)

    Altoé Gianmarco

    2011-09-01

    Full Text Available Abstract Background This study aims to evaluate relationship between three different clinical conditions: Major Depressive Disorders (MDD, Hashimoto Thyroiditis (HT and reduction in regional Cerebral Blood Flow (rCBF in order to explore the possibility that patients with HT and MDD have specific pattern(s of cerebral perfusion. Methods Design: Analysis of data derived from two separate data banks. Sample: 54 subjects, 32 with HT (29 women, mean age 38.8 ± 13.9; 22 without HT (19 women, mean age 36.5 ± 12.25. Assessment: Psychiatric diagnosis was carried out by Simplified Composite International Diagnostic Interview (CIDIS using DSM-IV categories; cerebral perfusion was measured by 99 mTc-ECD SPECT. Statistical analysis was done through logistic regression. Results MDD appears to be associated with left frontal hypoperfusion, left temporal hypoperfusion, diffuse hypoperfusion and parietal perfusion asymmetry. A statistically significant association between parietal perfusion asymmetry and MDD was found only in the HT group. Conclusion In HT, MDD is characterized by a parietal flow asymmetry. However, the specificity of rCBF in MDD with HT should be confirmed in a control sample with consideration for other health conditions. Moreover, this should be investigated with a longitudinally designed study in order to determine a possible pathogenic cause. Future studies with a much larger sample size should clarify whether a particular perfusion pattern is associated with a specific course or symptom cluster of MDD.

  3. Correcting partial volume artifacts of the arterial input function in quantitative cerebral perfusion MRI

    NARCIS (Netherlands)

    van Osch, MJP; Vonken, EJPA; Bakker, CJG; Viergever, MA

    2001-01-01

    To quantify cerebral perfusion with dynamic susceptibility contrast MRI (DSC-MRI), one needs to measure the arterial input function (AIF). Conventionally, one derives the contrast concentration from the DSC sequence by monitoring changes in either the amplitude or the phase signal on the assumption

  4. Temporal lobe epilepsy subtypes, differential patterns of cerebral perfusion on ictal SPECT

    NARCIS (Netherlands)

    Ho, SS; Berkovic, SF; McKay, WJ; Kalnins, RM; Bladin, PF

    1996-01-01

    Purpose: We studied cerebral perfusion patterns in the various subtypes of TLE, as determined by pathology and good outcome after temporal lobectomy (as confirmation of temporal origin). Methods: We studied clinical features and ictal technetium 99m hexamethyl-propyleneamineoxime (Tc-99m-HMPAO) sing

  5. Cerebral perfusion and metabolism in resuscitated patients with severe post-hypoxic encephalopathy

    NARCIS (Netherlands)

    Schaafsma, A.; de Jong, B M; Bams, J.L.; Haaxma-Reiche, H; Pruim, J; Zijlstra, J G

    2003-01-01

    Positron emission tomography (PET) was used for the study of regional cerebral perfusion and metabolism in eight patients with severe post-hypoxic encephalopathy, caused by cardiac arrest and resulting in a coma lasting for at least 24 h. Using this method, we aimed to identify regional vulnerabilit

  6. 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 cerebral...... metabolism (from arterial and internal jugular venous O(2), glucose and lactate differences), as well as the middle cerebral artery mean blood velocity (MCA V(mean); transcranial Doppler ultrasound) during a sustained static handgrip contraction at 40% of maximal voluntary contraction (n = 9) and the MCA V......(mean) during ergometer cycling (n = 8). Separate, randomized and counterbalanced trials were performed in control (no drug) conditions and following muscarinic cholinergic receptor blockade by glycopyrrolate. Glycopyrrolate increased resting heart rate from approximately 60 to approximately 110 beats min(-1...

  7. Modelling Brain Temperature and Perfusion for Cerebral Cooling

    Science.gov (United States)

    Blowers, Stephen; Valluri, Prashant; Marshall, Ian; Andrews, Peter; Harris, Bridget; Thrippleton, Michael

    2015-11-01

    Brain temperature relies heavily on two aspects: i) blood perfusion and porous heat transport through tissue and ii) blood flow and heat transfer through embedded arterial and venous vasculature. Moreover brain temperature cannot be measured directly unless highly invasive surgical procedures are used. A 3D two-phase fluid-porous model for mapping flow and temperature in brain is presented with arterial and venous vessels extracted from MRI scans. Heat generation through metabolism is also included. The model is robust and reveals flow and temperature maps in unprecedented 3D detail. However, the Karmen-Kozeny parameters of the porous (tissue) phase need to be optimised for expected perfusion profiles. In order to optimise the K-K parameters a reduced order two-phase model is developed where 1D vessels are created with a tree generation algorithm embedded inside a 3D porous domain. Results reveal that blood perfusion is a strong function of the porosity distribution in the tissue. We present a qualitative comparison between the simulated perfusion maps and those obtained clinically. We also present results studying the effect of scalp cooling on core brain temperature and preliminary results agree with those observed clinically.

  8. The cerebral imaging using vessel-around method in the perfusion CT of the human brain

    Science.gov (United States)

    Ahn, Choong-Il; Choi, Seung-Wook; Park, Seung-Chul; Shin, Yeong-Gil; Kim, Jae-Hyoung; Chong, Gi-Bong

    2005-04-01

    Perfusion CT has been successfully used as a functional imaging technique for diagnosis of patients with hyperacute stroke. However, the commonly used methods based on curve-fitting are time consuming. Numerous researchers have investigated to what extent Perfusion CT can be used for the quantitative assessment of cerebral ischemia and to rapidly obtain comprehensive information regarding the extent of ischemic damage in acute stroke patients. The aim of this study is to propose an alternative approach to rapidly obtain the brain perfusion mapping and to show the proposed cerebral flow imaging of the vessel and tissue in human brain be reliable and useful. Our main design concern was algorithmic speed, robustness and automation in order to allow its potential use in the emergency situation of acute stroke. To obtain a more effective mapping, we analyzed the signal characteristics of Perfusion CT and defined the vessel-around model which includes the vessel and tissue. We proposed a nonparametric vessel-around approach which automatically discriminates the vessel and tissue around vessel from non-interested brain matter stratifying the level of maximum enhancement of pixel-based TAC. The stratification of pixel-based TAC was executed using the mean and standard deviation of the signal intensity of each pixel and mapped to the cerebral flow imaging. The defined vessel-around model was used to show the cerebral flow imaging and to specify the area of markedly reduced perfusion with loss of function of still viable neurons. Perfusion CT is a fast and practical technique for routine clinical application. It provides substantial and important additional information for the selection of the optimal treatment strategy for patients with hyperacute stroke. The vessel-around approach reduces the computation time significantly when compared with the perfusion imaging using the GVF. The proposed cerebral imaging shows reliable results which are validated by physicians and

  9. Functional MRI of CO2 induced increase in cerebral perfusion

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B;

    1994-01-01

    The sensitivity of MR gradient echo imaging towards CO2 induced changes in cerebral blood flow was investigated in 10 normal subjects. The subjects were inhaling 5% and 7% CO2 and the experiments were carried out at 1.5 T (n = 6) and 2.0 T (n = 5), allowing a comparison of field strengths...

  10. Higher cerebral oxygen saturation may provide higher urinary output during continuous regional cerebral perfusion

    Directory of Open Access Journals (Sweden)

    Tomoyasu Takahiro

    2008-10-01

    Full Text Available Abstract Objective We examined the hypothesis that higher cerebral oxygen saturation (rSO2 during RCP is correlated with urinary output. Methods Between December 2002 and August 2006, 12 patients aged 3 to 61 days and weighing 2.6 to 3.4 kg underwent aortic arch repair with RCP. Urinary output and rSO2 were analyzed retrospectively. Data were assigned to either of 2 groups according to their corresponding rSO2: Group A (rSO2 ≦ 75% and Group B (rSO2 Results Seven and 5 patients were assigned to Group A and Group B, respectively. Group A was characterized by mean radial arterial pressure (37.9 ± 9.6 vs 45.8 ± 7.8 mmHg; P = 0.14 and femoral arterial pressure (6.7 ± 6.1 vs 20.8 ± 14.6 mmHg; P = 0.09 compared to Group B. However, higher urinary output during CPB (1.03 ± 1.18 vs 0.10 ± 0.15 ml·kg-1·h-1; P = 0.03. Furthermore our results indicate that a higher dose of Chlorpromazine was used in Group A (2.9 ± 1.4 vs 1.7 ± 1.0 mg/kg; P = 0.03. Conclusion Higher cerebral oxygenation may provide higher urinary output due to higher renal blood flow through collateral circulation.

  11. Statistical parametric mapping of Tc-99m HMPAO SPECT cerebral perfusion in the normal elderly

    Energy Technology Data Exchange (ETDEWEB)

    Turlakow, A.; Scott, A.M.; Berlangieri, S.U.; Sonkila, C.; Wardill, T.D.; Crowley, K.; Abbott, D.; Egan, G.F.; McKay, W.J.; Hughes, A. [Austin and Repatriation Medical Centre, Heidelberg, VIC (Australia). Departments of Nuclear Medicine and Centre for PET Neurology and Clinical Neuropsychology

    1998-06-01

    Full text: The clinical value of Tc-99m HMPAO SPECT cerebral blood flow studies in cognitive and neuropsychiatric disorders has been well described. Currently, interpretation of these studies relies on qualitative or semi- quantitative techniques. The aim of our study is to generate statistical measures of regional cerebral perfusion in the normal elderly using statistical parametric mapping (Friston et al, Wellcome Department of Cognitive Neurology, London, UK) in order to facilitate the objective analysis of cerebral blood flow studies in patient groups. A cohort of 20 healthy, elderly volunteers, aged 68 to 81 years, was prospectively selected on the basis of normal physical examination and neuropsychological testing. Subjects with risk factors, or a history of cognitive impairment were excluded from our study group. All volunteers underwent SPECT cerebral blood flow imaging, 30 minutes following the administration of 370 MBq Tc-99m HMPAO, on a Trionix Triad XLT triple-headed scanner (Trionix Research Laboratory Twinsburg, OH) using high resolution, fan-beam collimators resulting in a system resolution of 10 mm full width at half-maximum (FWHM). The SPECT cerebral blood flow studies were analysed using statistical parametric mapping (SPM) software specifically developed for the routine statistical analysis of functional neuroimaging data. The SPECT images were coregistered with each individual`s T1-weighted MR volume brain scan and spatially normalized to standardised Talairach space. Using SPM, these data were analyzed for differences in interhemispheric regional cerebral blood flow. Significant asymmetry of cerebral perfusion was detected in the pre-central gyrus at the 95th percentile. In conclusion, the interpretation of cerebral blood flow studies in the elderly should take into account the statistically significant asymmetry in interhemispheric pre-central cortical blood flow. In the future, clinical studies will be compared to statistical data sets in age

  12. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    Mendrik, A.M.; Vonken, E.J.; Ginneken, B. van; Jong, H.W. de; Riordan, A.; Seeters, T. van; Smit, E.J.; Viergever, M.A.; Prokop, M.

    2011-01-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiat

  13. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    A. Mendrik (Adrienne); E.J.P.A. Vonken; B.T.J. van Ginneken (Berbke); J.R. Riordan (John ); H.W.A.M. de Jong (Hugo); T. van Seeters (Tom); E.J. Smit (Ewoud); M.A. Viergever (Max); M. Prokop (Mathias)

    2011-01-01

    textabstractCerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of

  14. Dynamic Changes of the CT Perfusion Parameters in the Embolic Model of Cerebral Ischemia

    Institute of Scientific and Technical Information of China (English)

    陈唯唯; 漆剑频; 张进华; 黄文华; 宋金梅

    2004-01-01

    To study the dynamic changes of CT perfusion parameters during the first 12 h in the embolic cerebral ischemia models. Local cerebral ischemia model were established in 7 New Zealand white rabbits. All CT scans were performed with a GE Lightspeed 16 multislice CT. Following the baseline scan, further CT perfusion scans were performed at the same locations 20 min, 1-6 h and8, 10 and 12 h after the embolus delivery. Maps of all parameters were obtained by CT perfusion software at each time point. The brains, taken 12 h after the scan, were sliced corresponding to the positions of the CT slices and stained by 2,3,5-triphenyltetrazolium chloride (TTC). On the basis of the TTC results, the ischemicsides were divided into 3 regions: core, penumbra and the relatively normal region. The changes of all parameters were then divided into 3 stages. In the first two hours (the first stage), the CBV dropped more remarkably in the core than in the penumbra but rose slightly in the relatively normal region while the CBF decreased and MTT, TTP extended in all regions to varying degrees. In the 2nd-5th h (the second stage), all the parameters fluctuated slightly around a certain level. In the 5th-12th h (the third stage), the CBV and CBF dropped,and MTT and TTP were prolonged or shortened slightly in the core and penumbra though much notably in the former while the CBV, CBF roseand MTT, TTP were shortened remarkably in the relatively normal region. We experimentally demonstrated that the location and extent of cerebral ischemia could be accurately assessed by CT perfusion imaging. The pathophysiology of the ischemia could be reflected by the CT perfusion to varying degrees.

  15. Retinal vessel diameter changes induced by transient high perfusion pressure

    Institute of Scientific and Technical Information of China (English)

    Yin-Ying; Zhao; Ping-Jun; Chang; Fang; Yu; Yun-E; Zhao

    2014-01-01

    ·AIM: To investigate the effects of transient high perfusion pressure on the retinal vessel diameter and retinal ganglion cells.·METHODS: The animals were divided into four groups according to different infusion pressure and infusion time(60 mm Hg-3min, 60 mm Hg-5min, 100 mm Hg-3min, 100 mm Hg-5min). Each group consisted of six rabbits. The left eye was used as the experimental eye and the right as a control. Retinal vascular diameters were evaluated before, during infusion, immediately after infusion, 5min, 10 min and 30 min after infusion based on the fundus photographs. Blood pressure was monitored during infusion. The eyes were removed after 24 h.Damage to retinal ganglion cell(RGC) was analyzed by histology.·RESULTS: Retina became whiten and papilla optic was pale during perfusion. Measurements showed significant decrease in retinal artery and vein diameter during perfusion in all of the four groups at the proximal of the edge of the optic disc. The changes were significant in the 100 mm Hg-3min group and 100 mm Hg-5min group compared with 60 mm Hg-3min group(P 1=0.025, P 2=0.000).The diameters in all the groups recovered completely after 30 min of reperfusion. The number of RGC)showed no significant changes at the IOP in 100 mm Hg with5 min compared with contralateral untreated eye(P >0.05).·CONCLUSION: Transient fluctuations during infusion lead to temporal changes of retinal vessels, which could affect the retinal blood circulation. The RGCs were not affected by this transient fluctuation. Further studies are necessary to evaluate the effect of pressure during realtime phacoemusification on retinal blood circulation.

  16. Procedure for Decellularization of Rat Livers in an Oscillating-pressure Perfusion Device.

    Science.gov (United States)

    Hillebrandt, Karl; Polenz, Dietrich; Butter, Antje; Tang, Peter; Reutzel-Selke, Anja; Andreou, Andreas; Napierala, Hendrik; Raschzok, Nathanael; Pratschke, Johann; Sauer, Igor M; Struecker, Benjamin

    2015-01-01

    Decellularization and recellularization of parenchymal organs may enable the generation of functional organs in vitro, and several protocols for rodent liver decellularization have already been published. We aimed to improve the decellularization process by construction of a proprietary perfusion device enabling selective perfusion via the portal vein and/or the hepatic artery. Furthermore, we sought to perform perfusion under oscillating surrounding pressure conditions to improve the homogeneity of decellularization. The homogeneity of perfusion decellularization has been an underestimated factor to date. During decellularization, areas within the organ that are poorly perfused may still contain cells, whereas the extracellular matrix (ECM) in well-perfused areas may already be affected by alkaline detergents. Oscillating pressure changes can mimic the intraabdominal pressure changes that occur during respiration to optimize microperfusion inside the liver. In the study presented here, decellularized rat liver matrices were analyzed by histological staining, DNA content analysis and corrosion casting. Perfusion via the hepatic artery showed more homogenous results than portal venous perfusion did. The application of oscillating pressure conditions improved the effectiveness of perfusion decellularization. Livers perfused via the hepatic artery and under oscillating pressure conditions showed the best results. The presented techniques for liver harvesting, cannulation and perfusion using our proprietary device enable sophisticated perfusion set-ups to improve decellularization and recellularization experiments in rat livers.

  17. A multimodal imaging study on spatial pattern of cerebral perfusion change caused by symptomatic unilateral carotid artery stenosis

    Directory of Open Access Journals (Sweden)

    Jian-rui LI

    2015-03-01

    Full Text Available Objective To investigate the spatial pattern of cerebral perfusion decrease resulting from symptomatic unilateral carotid artery stenosis and to assess the relationship between degrees of stenosis and cerebral blood flow (CBF.  Methods CT angiography (CTA and arterial spin labeling (ASL MRI cerebral perfusion were performed in 22 patients with symptomatic unilateral carotid artery stenosis. Diagnosis of carotid artery stenosis and measurement of stenosis degrees was performed by using CTA; cerebral perfusion was determined by ASL. Voxel-based analysis (VBA were applied to observe perfusion changes in patients with mild stenosis and moderate to severe stenosis, and spatial pattern of cerebral perfusion changes caused by carotid artery stenosis. Analysis based on region of interest (ROI was used to explore the relationship between degrees of stenosis and CBF. Results Twenty-two patients with symptomatic unilateral carotid artery stenosis (13 in the left side and 9 in the right included 13 cases with mild stenosis and 9 cases with moderate to severe stenosis. Compared to those with mild stenosis, patients with moderate to severe stenosis showed reduced CBF in bilateral (especially in the affected side parietal lobes (t = - 2.382, P = 0.014, frontal lobes (t = - 2.354, P = 0.015 and centrum semiovale (t = - 2.283, P = 0.017, and was basically located in bilateral cerebral watershed area. Furthermore, perfusion in these areas was negatively correlated with the degree of stenosis (r = - 0.479, P = 0.024.  Conclusions Symptomatic unilateral carotid artery stenosis may result in cerebral perfusion decreases in bilateral (particularly in the affected side watershed area and cerebral blood flow is negatively correlated with the degree of stenosis. DOI: 10.3969/j.issn.1672-6731.2015.02.006

  18. Intensive blood pressure control affects cerebral blood flow in type 2 diabetes mellitus patients

    DEFF Research Database (Denmark)

    Kim, Yu-Sok; Davis, Shyrin C A T; Truijen, Jasper;

    2011-01-01

    Type 2 diabetes mellitus is associated with microvascular complications, hypertension, and impaired dynamic cerebral autoregulation. Intensive blood pressure (BP) control in hypertensive type 2 diabetic patients reduces their risk of stroke but may affect cerebral perfusion. Systemic hemodynamic...... variables and transcranial Doppler-determined cerebral blood flow velocity (CBFV), cerebral CO2 responsiveness, and cognitive function were determined after 3 and 6 months of intensive BP control in 17 type 2 diabetic patients with microvascular complications (T2DM+), in 18 diabetic patients without (T2DM......-) microvascular complications, and in 16 nondiabetic hypertensive patients. Cerebrovascular reserve capacity was lower in T2DM+ versus T2DM- and nondiabetic hypertensive patients (4.6±1.1 versus 6.0±1.6 [P

  19. Effect of propofol and remifentanil on cerebral perfusion and oxygenation in pigs

    DEFF Research Database (Denmark)

    Mikkelsen, Mai Louise Grandsgaard; Ambrus, Rikard; Miles, James Edward

    2016-01-01

    in human but also in veterinary anaesthesia to preserve optimal regulation of cerebral haemodynamics. Propofol and remifentanil are widely used in neuroanaesthesia and are increasingly used in experimental animal studies. In translational models, the pig has advantages compared to small laboratory animals......The objective of this review is to evaluate the existing literature with regard to the influence of propofol and remifentanil total intravenous anaesthesia (TIVA) on cerebral perfusion and oxygenation in healthy pigs. Anaesthesia has influence on cerebral haemodynamics and it is important not only...... and oxygenation (CPO). The evidence evaluated in this systematic review is limited, not focused on propofol and remifentanil and possibly influenced by factors of potential importance for CPO assessment. In one study of healthy pigs, CPO measures were within normal ranges following propofol...

  20. Single photon emission CT perfusion imaging of cerebral blood flow of early syphilis patients

    Institute of Scientific and Technical Information of China (English)

    施辛; 吴锦昌; 刘增礼; 唐军; 苏玉华

    2003-01-01

    Objective To injvestigate the cerebral blood flow of patients with early syphilis. Methods 99Tcm-ECD as brain perfusion imaging agent was used in single photon emission computed tomography (SPECT) for 32 patients with early syphilis and 15 controls. Visual analyses were made on every BSPECT image. Results The 32 patients with early syphilis had general, patchy hypoperfusion of cerebral blood flow. Fourteen of the 32 patients had 48 episodes of marked patchy hypoperfusion of rCBF. The responsible areas of hypoperfusion in a patchy distribution involved the left frontal lobe (6 episodes), right frontal lobe (3), left parietal lobe (7), right parietal lobe (6), left temporal lobe (11), right temporal lobe (5), left occipital lobe (3), left basal ganglia (3), cerebellum (1), and nerve nuceus (1). No abnormality was found in the control group.Conclusions Cerebral blood flow abnormalities exist in patients with early syphilis. General patchy hypoperfusion on SPECT imaging is common.

  1. Vasopressin content in the cerebrospinal fluid and fluid perfusing cerebral ventricles in rats after the afferent vagus nerve fibres stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Orlowska-Majdak, M.; Traczyk, W.Z. [Akademia Medyczna, Lodz (Poland). Katedra Fizjologii

    1996-12-31

    Experiments were carried out on male rats in urethane anaesthesia. Cerebroventricular system was perfused with McIlwain-Rodniht`s solution from lateral ventricles to cerebellomedullary cistern. Both vagus nerves were cut and the central ends of the nerves were electrically stimulated during the collection of the third 30-min portion of perfusing fluid. Vasopressin (AVP) was determined by radioimmunoassay in samples of the cerebrospinal fluid (CSF) (the first portion) and in five successive samples of the perfusing fluid. AVP concentration in the CSF was several times greater than in the fluid perfusing cerebral ventricles. Alternate electrical stimulation of both vagus nerves did not change considerably the release of AVP into the fluid perfusing the cerebral ventricles in rat, although a certain upward tendency could be observed. It seems that only AVP raised in circulating blood and not in CSF, after vagus nerves stimulation may act on the central nervous structures. (author). 37 refs, 3 figs, 1 tab.

  2. Cerebral misery perfusion diagnosed using hypercapnic blood-oxygenation-level-dependent contrast functional magnetic resonance imaging: a case report

    Directory of Open Access Journals (Sweden)

    D'Souza Olympio

    2010-02-01

    Full Text Available Abstract Introduction Cerebral misery perfusion represents a failure of cerebral autoregulation. It is an important differential diagnosis in post-stroke patients presenting with collapses in the presence of haemodynamically significant cerebrovascular stenosis. This is particularly the case when cortical or internal watershed infarcts are present. When this condition occurs, further investigation should be done immediately. Case presentation A 50-year-old Caucasian man presented with a stroke secondary to complete occlusion of his left internal carotid artery. He went on to suffer recurrent seizures. Neuroimaging demonstrated numerous new watershed-territory cerebral infarcts. No source of arterial thromboembolism was demonstrable. Hypercapnic blood-oxygenation-level-dependent-contrast functional magnetic resonance imaging was used to measure his cerebrovascular reserve capacity. The findings were suggestive of cerebral misery perfusion. Conclusions Blood-oxygenation-level-dependent-contrast functional magnetic resonance imaging allows the inference of cerebral misery perfusion. This procedure is cheaper and more readily available than positron emission tomography imaging, which is the current gold standard diagnostic test. The most evaluated treatment for cerebral misery perfusion is extracranial-intracranial bypass. Although previous trials of this have been unfavourable, the results of new studies involving extracranial-intracranial bypass in high-risk patients identified during cerebral perfusion imaging are awaited. Cerebral misery perfusion is an important and under-recognized condition in which emerging imaging and treatment modalities present the possibility of practical and evidence-based management in the near future. Physicians should thus be aware of this disorder and of recent developments in diagnostic tests that allow its detection.

  3. Arterial pressure and cerebral blood flow variability: friend or foe? A review

    Directory of Open Access Journals (Sweden)

    Caroline Alice Rickards

    2014-04-01

    Full Text Available Variability in arterial pressure and cerebral blood flow has traditionally been interpreted as a marker of cardiovascular decompensation, and has been associated with negative clinical outcomes across varying time scales, from impending orthostatic syncope to an increased risk of stroke. Emerging evidence, however, suggests that increased hemodynamic variability may, in fact, be protective in the face of acute challenges to perfusion, including significant central hypovolemia and hypotension (including hemorrhage, and during cardiac bypass surgery. This review presents the dichotomous views on the role of hemodynamic variability on clinical outcome, including the physiological mechanisms underlying these patterns, and the potential impact of increased and decreased variability on cerebral perfusion and oxygenation. We suggest that reconciliation of these two apparently discrepant views may lie in the time scale of hemodynamic variability; short time scale variability appears to be cerebroprotective, while mid to longer term fluctuations are associated with primary and secondary end-organ dysfunction.

  4. Neuroradiological findings in primary progressive aphasia: CT, MRI and cerebral perfusion SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Sinnatamby, R. [Dept. of Radiology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Antoun, N.A. [Dept. of Radiology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Freer, C.E.L. [Dept. of Radiology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Miles, K.A. [Dept. of Nuclear Medicine, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Hodges, J.R. [Dept. of Neurology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom)

    1996-04-01

    Primary progressive aphasia (PPA) is defined as progressive decline in language for 2 or more years with preservation of activities of daily living and general cognitive functions. Whereas the clinical features of this syndrome have been well documented, the neuroradiological findings have not been studied systematically. We studied 13 patients with PPA retrospectively: 10 underwent CT, 12 MRI and 12 cerebral perfusion studies using {sup 99m}Tc-HMPAO SPECT. CT and MR images were scored for focal atrophy by two independent assessors. Initial qualitative assessment of SPECT images was confirmed by quantitative analysis. CY was normal in 5 patients. Focal atrophy, affecting predominantly the left temporal lobe, was seen in 4 of 10 patients on CT, and 10 of 12 on MRI. Atrophy was localised primarily to the superior and middle temporal gyri on MRI. All 12 patients who underwent SPECT had unilateral temporal lobe perfusion defects, in 2 patients of whom MRI was normal. CT is relatively insensitive to focal abnormalities in PPA; MRI and SPECT are the imaging modalities of choice. MRI allows accurate, specific localisation of atrophy with the temporal neocortex. SPECT may reveal a functional decrease in cerebral perfusion prior to establishment of structural change. (orig.)

  5. Evaluation of cerebral perfusion imaging with N-isopropyl-p-[{sup 123}I]iodoamphetamine (IMP) in the cases of antiphospholipid syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Toru; Nanbu, Ichiro; Tohyama, Junko; Ohba, Satoru [Nagoya City Univ. (Japan). Faculty of Medicine

    1995-01-01

    Five cases of antiphospholipid syndrome with mild headache, but without any neurological deficits and abnormal findings by CT and MRI, were examined by cerebral blood perfusion SPECT using N-isopropyl-p-[{sup 123}I] iodoamphetamine (IMP). Although three cases were performed quantification of cerebral blood flow with a microsphere method simultaneously, their values were within normal limits. Two of them showed focal low perfusion areas. One case had relatively low perfusion areas in the bilateral occipital lobes and the right temporal lobe, which improved after treatment. One of two had low perfusion in the bilateral occipital lobes. Other three cases only showed ununiformity of radioisotope uptake on the cerebral blood perfusion SPECT. Low perfusion areas in antiphospholipid syndrome might be caused by microarterial thrombosis, microvenous thrombosis or spasms, although they could be reversible. As early irreversible progress of cerebral blood flow, cerebral blood flow SPECT should be performed in cases of antiphospholipid syndrome with neurological complainments. (author).

  6. Cerebral Perfusion Enhancing Interventions: A New Strategy for the Prevention of Alzheimer Dementia.

    Science.gov (United States)

    de la Torre, Jack C

    2016-09-01

    Cardiovascular and cerebrovascular diseases are major risk factors in the development of cognitive impairment and Alzheimer's disease (AD). These cardio-cerebral disorders promote a variety of vascular risk factors which in the presence of advancing age are prone to markedly reduce cerebral perfusion and create a neuronal energy crisis. Long-term hypoperfusion of the brain evolves mainly from cardiac structural pathology and brain vascular insufficiency. Brain hypoperfusion in the elderly is strongly associated with the development of mild cognitive impairment (MCI) and both conditions are presumed to be precursors of Alzheimer dementia. A therapeutic target to prevent or treat MCI and consequently reduce the incidence of AD aims to elevate cerebral perfusion using novel pharmacological agents. As reviewed here, the experimental pharmaca include the use of Rho kinase inhibitors, neurometabolic energy boosters, sirtuins and vascular growth factors. In addition, a compelling new technique in laser medicine called photobiomodulation is reviewed. Photobiomodulation is based on the use of low level laser therapy to stimulate mitochondrial energy production non-invasively in nerve cells. The use of novel pharmaca and photobiomodulation may become important tools in the treatment or prevention of cognitive decline that can lead to dementia.

  7. Arterial spin labelling MRI for assessment of cerebral perfusion in children with moyamoya disease: comparison with dynamic susceptibility contrast MRI

    Energy Technology Data Exchange (ETDEWEB)

    Goetti, Robert [University Children' s Hospital Zurich, Department of Diagnostic Imaging, Zurich (Switzerland); University Hospital Zurich, Department of Diagnostic and Interventional Radiology, Zurich (Switzerland); O' Gorman, Ruth [University Children' s Hospital Zurich, Center for MR Research, Zurich (Switzerland); Khan, Nadia [University Children' s Hospital Zurich, Moyamoya Center, Division of Neurosurgery, Department of Surgery, Zurich (Switzerland); Kellenberger, Christian J.; Scheer, Ianina [University Children' s Hospital Zurich, Department of Diagnostic Imaging, Zurich (Switzerland)

    2013-05-15

    This study seeks to evaluate the diagnostic accuracy of cerebral perfusion imaging with arterial spin labelling (ASL) MR imaging in children with moyamoya disease compared to dynamic susceptibility contrast (DSC) imaging. Ten children (7 females; age, 9.2 {+-} 5.4 years) with moyamoya disease underwent cerebral perfusion imaging with ASL and DSC on a 3-T MRI scanner in the same session. Cerebral perfusion images were acquired with ASL (pulsed continuous 3D ASL sequence, 32 axial slices, TR = 5.5 s, TE = 25 ms, FOV = 24 cm, matrix = 128 x 128) and DSC (gradient echo EPI sequence, 35 volumes of 28 axial slices, TR = 2,000 ms, TE = 36 ms, FOV = 24 cm, matrix = 96 x 96, 0.2 ml/kg Gd-DOTA). Cerebral blood flow maps were generated. ASL and DSC images were qualitatively assessed regarding perfusion of left and right ACA, MCA, and PCA territories by two independent readers using a 3-point-Likert scale and quantitative relative cerebral blood flow (rCBF) was calculated. Correlation between ASL and DSC for qualitative and quantitative assessment and the accuracy of ASL for the detection of reduced perfusion per territory with DSC serving as the standard of reference were calculated. With a good interreader agreement ({kappa} = 0.62) qualitative perfusion assessment with ASL and DSC showed a strong and significant correlation ({rho} = 0.77; p < 0.001), as did quantitative rCBF (r = 0.79; p < 0.001). ASL showed a sensitivity, specificity and accuracy of 94 %, 93 %, and 93 % for the detection of reduced perfusion per territory. In children with moyamoya disease, unenhanced ASL enables the detection of reduced perfusion per vascular territory with a good accuracy compared to contrast-enhanced DSC. (orig.)

  8. Effect of cerebral ventricles perfusion with naloxone on trigemino-hypoglossal reflex in rats.

    Science.gov (United States)

    Zubrzycka, M; Janecka, A

    2001-02-02

    The goal of this study was to determine whether opioid receptor antagonist naloxone abolishes the influence of periaqueductal central gray (PAG) on nociceptive evoked tongue jerks (ETJ) -- a trigemino-hypoglossal reflex induced by tooth pulp stimulation. In rats under chloralose anesthesia three series of experiments were performed. In the first two groups perfusions of lateral ventricles-cerebellomedullary cistern with McIlwain-Rodnight's solution and naloxone were carried out. In group 3 naloxone was infused through a catheter through the jugular vein. The amplitudes of tongue jerks induced by tooth pulp stimulation were recorded during subsequent 10 min perfusions. Mean amplitude of tongue movements induced by tooth pulp stimulation was regarded as the indicator of the magnitude of trigemino-hypoglossal reflex. We observed that perfusion of the cerebral ventricles with naloxone (100 nmol/ml) increased the trigemino-hypoglossal reflex up to 143%. The amplitude of ETJ was significantly reduced during PAG stimulation with a train of electrical impulses. After obtaining a significant -- 93% -- inhibition of ETJ (7% of the control), naloxone (100 nmol/ml) was added to the perfusion fluid. This led to a significant increase of the reflex up to 68%. Infusion of naloxone through the jugular vein did not affect the reflex. The above results suggest that the inhibition of ETJ due to PAG stimulation is partially reversed by naloxone and mediated via interactions with endogenous opioid systems involved in modulation of nociception.

  9. Intraoperative imaging of cortical cerebral perfusion by time-resolved thermography and multivariate data analysis

    Science.gov (United States)

    Steiner, Gerald; Sobottka, Stephan B.; Koch, Edmund; Schackert, Gabriele; Kirsch, Matthias

    2011-01-01

    A new approach to cortical perfusion imaging is demonstrated using high-sensitivity thermography in conjunction with multivariate statistical data analysis. Local temperature changes caused by a cold bolus are imaged and transferred to a false color image. A cold bolus of 10 ml saline at ice temperature is injected systemically via a central venous access. During the injection, a sequence of 735 thermographic images are recorded within 2 min. The recorded data cube is subjected to a principal component analysis (PCA) to select slight changes of the cortical temperature caused by the cold bolus. PCA reveals that 11 s after injection the temperature of blood vessels is shortly decreased followed by an increase to the temperature before the cold bolus is injected. We demonstrate the potential of intraoperative thermography in combination with multivariate data analysis to image cortical cerebral perfusion without any markers. We provide the first in vivo application of multivariate thermographic imaging.

  10. PERFUSION PRESSURE AND RENAL BLOOD FLOW: THEIR RELATIONSHIP AND DIFFERENCES

    Directory of Open Access Journals (Sweden)

    Carlos G. Musso, MD. PhD.1,2, Manuel Vilas, MD.

    2014-05-01

    Full Text Available The concepts of renal perfusion pressure (RPP and renal blood flow (RBF are usually confused, but although they are intimately related, they are not strictly the same. RPP originates from the minute cardiac volume and is, therefore, the cause of RBF, which generates glomerular filtration and as a consequence, also induces the urinary flow. On the other hand, whereas RPP can be subject to fluctuations, the same happens to RBF though at a much lower level due to the existence of physiological mechanisms, such as self-regulation of the flow and tubule-glomerular feed-back. We conclude that there is a dependence of the RBF in relation with RPP, with the former acting as the final responsible of the glomerular filtration.

  11. Vascular risk factors, atherosclerosis, cerebral white matter lesions and cerebral perfusion in a population-based study

    Energy Technology Data Exchange (ETDEWEB)

    Claus, J.J. [Dept. of Epidemiology and Biostatistics, Erasmus Univ. Medical School, Rotterdam (Netherlands); Breteler, M.M.B. [Dept. of Epidemiology and Biostatistics, Erasmus Univ. Medical School, Rotterdam (Netherlands); Hasan, D. [Dept. of Neurology, Univ. Hospital Rotterdam Dijkzigt, Rotterdam (Netherlands); Krenning, E.P. [Dept. of Nuclear Medicine, Univ. Hospital Rotterdam Dijkzigt, Rotterdam (Netherlands); Bots, M.L. [Dept. of Epidemiology and Biostatistics, Erasmus Univ. Medical School, Rotterdam (Netherlands); Grobbee, D.E. [Dept. of Epidemiology and Biostatistics, Erasmus Univ. Medical School, Rotterdam (Netherlands); Swieten, J.C. van [Dept. of Neurology, Univ. Hospital Rotterdam Dijkzigt, Rotterdam (Netherlands); Harskamp, F. van [Dept. of Neurology, Univ. Hospital Rotterdam Dijkzigt, Rotterdam (Netherlands); Hofman, A. [Dept. of Epidemiology and Biostatistics, Erasmus Univ. Medical School, Rotterdam (Netherlands)

    1996-06-01

    We studied risk factors for cerebral vascular disease (blood pressure and hypertension, factor VIIc, factor VIIIc, fibrinogen), indicators of atherosclerosis (intima-media thickness and plaques in the carotid artery) and cerebral white matter lesions in relation to regional cerebral blood flow (rCBF) in 60 persons (aged 65-85 years) recruited from a population-based study. rCBF was assessed with single-photon emission tomography using technetium-99m d,l-hexamethylpropylene amine oxime ({sup 99m}Tc-HMPAO). Statistical analysis was performed with multiple linear regression with adjustment for age, sex and ventricle-to-brain ratio. A significant positive association was found between systolic and diastolic blood pressure and temporo-parietal rCBF. In analysis with quartiles of the distribution, we found a threshold effect for the relation of low diastolic blood pressure ({<=}60 mmHg) and low temporo-parietal rCBF. Levels of plasma fibrinogen were inversely related to parietal rCBF, with a threshold effect of high fibrinogen levels (>3.2 g/l) and low rCBF. Increased atherosclerosis was related to low rCBF in all cortical regions, but these associations were not significant. No consistent relation was observed between severity of cerebral white matter lesions and rCBF. Our results may have implications for blood pressure control in the elderly population. (orig.)

  12. Xueshuantong improves cerebral blood perfusion in elderly patients with lacunar infarction

    Institute of Scientific and Technical Information of China (English)

    Qifeng Gui; Yunmei Yang; Shihong Ying; Minming Zhang

    2013-01-01

    A total of 64 patients with acute lacunar infarction were enrolled within 24 hours of onset. The patients received conventional therapy (antiplatelet drugs and hypolipidemic drugs) alone or conventional therapy plus 450 mg Xueshuantong once a day. The main ingredient of the Xueshuantong lyophilized powder used for injection was Panax notoginseng saponins. Assessments were made at admission and at discharge using the National Institutes of Health Stroke Scale, the Activity of Daily Living and the Mini-Mental State Examination. Additionally, the relative cerebral blood flow, relative cerebral blood volume and relative mean transit time in the region of interest were calculated within 24 hours after the onset of lacunar infarction, using dynamic susceptibility contrast magnetic resonance perfusion imaging technology. Patients underwent a follow-up MRI scan after 4 weeks of treatment. There was an improvement in the Activity of Daily Living scores and a greater reduction in the scores on the National Institutes of Health Stroke Scale in the treatment group than in the control group. However, the Mini-Mental State Examination scores showed no significant differences after 4 weeks of treatment. Compared with the control group, the relative cerebral blood flow at discharge had increased and showed a greater improvement in the treatment group. Furthermore, there was a reduction in the relative mean transit time at discharge and the value was lower in the treatment group than in the control group. The experimental findings indicate that Xueshuantong treatment improves neurological deficits in elderly patients with lacunar infarction, and the mechanism may be related to increased cerebral perfusion.

  13. Challenges in understanding the impact of blood pressure management on cerebral oxygenation in the preterm brain

    Directory of Open Access Journals (Sweden)

    Aminath eAzhan

    2012-12-01

    Full Text Available Systemic hypotension in preterm infants has been related to increased mortality, cerebrovascular lesions and neurodevelopmental morbidity. Treatment of hypotension with inotropic medications aims at preservation of end organ perfusion and oxygen delivery, especially the brain. The common inotropic medications in preterm infants include dopamine, dobutamine, adrenalin, with adjunctive use of corticosteroids in cases of refractory hypotension. Whether maintenance of mean arterial blood pressure (MAP by use of inotropic medication is neuroprotective or not remains unclear. This review explores the different inotropic agents and their effects on perfusion and oxygenation in the preterm brain, in clinical studies as well as in animal models. Dopamine and adrenalin, because of their -adrenergic vasoconstrictor actions, have raised concerns of reduction in cerebral blood flow (CBF. Several studies in hypotensive preterm infants have shown that dopamine elevates CBF together with increased MAP, in keeping with limited cerebro-autoregulation. Adrenaline is also effective in raising cerebral perfusion together with MAP in preterm infants. Experimental studies in immature animals show no cerebro-vasoconstrictive effects of dopamine or adrenaline, but demonstrate the consistent findings of increased cerebral perfusion and oxygenation with the use of dopamine, dobutamine and adrenaline, alongside with raised MAP. Both clinical and animal studies report the transitory effects of adrenaline in increasing plasma lactate, and blood glucose, which might render its use as a 2nd line therapy. To investigate the cerebral effects of inotropic agents in long-term outcome in hypotensive preterm infants, carefully designed prospective research possibly including preterm infants with permissive hypotension is required. Preterm animal models would be useful in investigating the relationship between the physiological effects of inotropes and histopathology outcomes in

  14. CT measurement of changes in cerebral perfusion in patients with asymptomatic carotid artery stenosis undergoing carotid stenting prior to cardiac surgery: "proof of principle"

    NARCIS (Netherlands)

    Heyden, J. Van der; Waaijer, A.; Wouter, E.S. Van; Neerven, D. van; Sonker, U.; Suttorp, M.J.; Bal, E.T.; Prokop, M.

    2011-01-01

    AIMS: To identify asymptomatic patients with impaired cerebral perfusion using CT perfusion (CTP) technique during staged carotid stenting (CAS) and cardiac surgery. METHODS AND RESULTS: This is a prospective, non-randomised study in 16 neurologically asymptomatic patients designed to analyse cerebr

  15. Noninvasive measurements of regional cerebral perfusion in preterm and term neonates by magnetic resonance arterial spin labeling

    DEFF Research Database (Denmark)

    Miranda Gimenez-Ricco, Maria Jo; Olofsson, K; Sidaros, Karam

    2006-01-01

    Magnetic resonance arterial spin labeling (ASL) at 3 Tesla has been investigated as a quantitative technique for measuring regional cerebral perfusion (RCP) in newborn infants. RCP values were measured in 49 healthy neonates: 32 preterm infants born before 34 wk of gestation and 17 term-born neon......Magnetic resonance arterial spin labeling (ASL) at 3 Tesla has been investigated as a quantitative technique for measuring regional cerebral perfusion (RCP) in newborn infants. RCP values were measured in 49 healthy neonates: 32 preterm infants born before 34 wk of gestation and 17 term...

  16. Cerebral perfusion, oxygenation and metabolism during exercise in young and elderly individuals

    DEFF Research Database (Denmark)

    Fisher, James P; Hartwich, Doreen; Seifert, Thomas

    2013-01-01

    artery blood velocity (MCA V(mean)), mean arterial pressure (MAP), cardiac output (CO) and the partial pressure of arterial carbon dioxide (PaCO(2)) were measured. Blood samples were obtained from the right internal jugular vein and brachial artery to determine concentration differences for oxygen (O(2......)), glucose and lactate across the brain. The molar ratio between the cerebral uptake of O(2) versus carbohydrate (O(2)-carbohydrate index; O(2) / [glucose + 0.5 lactate]; OCI), the cerebral metabolic rate of O(2) (CMRO(2)) and changes in mitochondrial O(2) tension (P(mito)O(2)) were calculated. W...

  17. Effect of Intracranial Pressure and Cerebral Perfusion Pressure in Patients with Supratentorial Brain Tumors after Induction of Different Anesthesia%不同麻醉药物对幕上脑肿瘤患者诱导麻醉后颅内压及脑灌注压的影响

    Institute of Scientific and Technical Information of China (English)

    谭明; 万正嵩

    2014-01-01

    Objective:To explore the different anesthetic agents on intracranial pressure and cerebral perfusion pressure in patients with supratentorial brain tumors after induction of anesthesia.Methods:60 patients receiving craniotomy were randomly divided into observation group and the control group, the observation group patients used fentany 1μg/kg+midazolam 0.1mg/kg+propofol 2 mg/kg+succinylcholine 2mg/kg control group patients used sufentanil 1μg/kg+midazolam 0.1mg/kg+propofol 2 mg/kg+succinylcholine 2mg/kg.ICP and CPP changes of the two groups before and after anesthesia were compared. Results: (1)ICP comparison intubation immediately after intubation 5min,after intubation 15min after incision,two groups of patients ICP gradually increased,compared with before the induction of the differences were statistically significant (P<0.05).The two groups of patients after open flap ICP gradually decreased,but still higher than before the induction level (P<0.05),the two groups of patients after open subdural ICP were restored to the induction of the level before.Observation group patients CPP after intubation decreased gradually,after 15min,after incision and open the flap after intubation were significantly lower than before the induction,the difference was statistically significant (P<0.05),gradually open the dura mater liter high. Immediately after the control group in patients with CPP in intubation, intubation after 15min,after incision,open flap and open subdural significantly lower than before the induction,which,immediately after intubation,intubation after 15min,skin incision and open flap after significantly lower than that of the observation group,the differences were statistically significant (P<0.05). Conclusion:After induction of anesthesia in patients with supratentorial brain tumor the ICP elevated,the CPP reduce,compare with compared with fentanyl, sufentanil is more pronounced impact on ICP and CPP.%目的:探讨不同麻醉药物对幕上脑肿瘤患

  18. Effect of Acupuncture Signal after Brachial Plexus Blockade on Cerebral Blood Perfusion and Brain Cell Function

    Institute of Scientific and Technical Information of China (English)

    任永功; 郭长春; 贾少微

    2003-01-01

    Objective: Using single photon emission computed tomography (SPECT) to observe the influence of the up-transmitting of acupuncture signal into the brain in health volunteers whose nerve trunk was blocked by anesthetics. Methods: Thirty-one healthy volunteers were divided into two groups, the control group of 20 cases, and the brachial plexus blockade (BPB) group of 11 cases, with supraclavicular BPB route adopted. With the control group 2 acupoints were randomly selected (Hegu and Quchi of both sides), while with the BPB group Hegu and Quchi of anesthetic arm side were selected. Siemens ECAM/ICON SPECT system was used to conduct brain imaging using double imaging assay before acupuncture and 99mTc-ECD imaging agent during acupuncture for cerebral perfusion. The data were quantitatively analyzed by blood functional changing rate (BFCR%) mathematics model. Results: Before acupuncture, the control and BPB groups showed insignificant change by SPECT, but after electro-acupuncture (EA), the control group displayed improved motor and sensory cortex excitability in basal nuclei, contra-lateral thalamus, parietal and frontal lobe; while BPB group was characterized with reduction of the blood perfusion and cell function of contra-lateral thalamus of anesthetized arm. The difference between the two groups was significant (P<0.01). Conclusion: (1) After BPB, the up-transmitting of the acupuncture signal via upper limb into the brain, and its strength was impaired or blocked; (2) After BPB, the effect of acupuncture on cerebral perfusion and brain cell function of contra-lateral thalamus was impaired or blocked.

  19. Application value of CT perfusion imaging with acetazolamide challenge test in the diagnosis of chronic cerebral insufficiency

    Institute of Scientific and Technical Information of China (English)

    高轩

    2014-01-01

    Objective To explore the CT perfusion imaging with acetazolamide(ACZ)challenge test in the diagnosis of chronic cerebral insufficiency.Methods 100 patients undergoing health examination in our hospital from Aug2009 to Feb 2011 were chosen,52 patients diagnosed as chronic cerebral insufficiency were defined as the case group,and the remaining 48 cases of healthy elderly people were defined as the control group.The brain CT

  20. CT perfusion during delayed cerebral ischemia after subarachnoid hemorrhage: distinction between reversible ischemia and ischemia progressing to infarction

    Energy Technology Data Exchange (ETDEWEB)

    Cremers, Charlotte H.P. [University Medical Center Utrecht, Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, PO Box 85500, Utrecht, Utrecht (Netherlands); University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Vos, Pieter C. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Schaaf, Irene C. van der; Velthuis, Birgitta K.; Dankbaar, Jan Willem [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Vergouwen, Mervyn D.I.; Rinkel, Gabriel J.E. [University Medical Center Utrecht, Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, PO Box 85500, Utrecht, Utrecht (Netherlands)

    2015-09-15

    Delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH) can be reversible or progress to cerebral infarction. In patients with a deterioration clinically diagnosed as DCI, we investigated whether CT perfusion (CTP) can distinguish between reversible ischemia and ischemia progressing to cerebral infarction. From a prospectively collected series of aSAH patients, we included those with DCI, CTP on the day of clinical deterioration, and follow-up imaging. In qualitative CTP analyses (visual assessment), we calculated positive and negative predictive value (PPV and NPV) with 95 % confidence intervals (95%CI) of a perfusion deficit for infarction on follow-up imaging. In quantitative analyses, we compared perfusion values of the least perfused brain tissue between patients with and without infarction by using receiver-operator characteristic curves and calculated a threshold value with PPV and NPV for the perfusion parameter with the highest area under the curve. In qualitative analyses of 33 included patients, 15 of 17 patients (88 %) with and 6 of 16 patients (38 %) without infarction on follow-up imaging had a perfusion deficit during clinical deterioration (p = 0.002). Presence of a perfusion deficit had a PPV of 71 % (95%CI: 48-89 %) and NPV of 83 % (95%CI: 52-98 %) for infarction on follow-up. Quantitative analyses showed that an absolute minimal cerebral blood flow (CBF) threshold of 17.7 mL/100 g/min had a PPV of 63 % (95%CI: 41-81 %) and a NPV of 78 % (95%CI: 40-97 %) for infarction. CTP may differ between patients with DCI who develop infarction and those who do not. For this purpose, qualitative evaluation may perform marginally better than quantitative evaluation. (orig.)

  1. Real-time ultrasound perfusion imaging in acute stroke: assessment of cerebral perfusion deficits related to arterial recanalization.

    Science.gov (United States)

    Bolognese, Manuel; Artemis, Dimitrios; Alonso, Angelika; Hennerici, Michael G; Meairs, Stephan; Kern, Rolf

    2013-05-01

    We investigated whether real-time ultrasound perfusion imaging (rt-UPI) is able to detect perfusion changes related to arterial recanalization in the acute phase of middle cerebral artery (MCA) stroke. Twenty-four patients with acute territorial MCA stroke were examined with rt-UPI and transcranial color-coded duplex ultrasound (TCCD). Ultrasound studies were consecutively performed within 24 h and 72-96 h after stroke onset. Real-time UPI parameters of bolus kinetics (time to peak, rt-TTP) and of refill kinetics (plateau A and slope β of the exponential replenishment curve) were calculated from regions of interest of ischemic versus normal brain tissue; these parameters were compared between early and follow-up examinations in patients who recanalized. At the early examination, there was a delay of rt-TTP in patients with MCA occlusion (rt-TTP [s]: 13.09 ± 3.21 vs. 10.16 ± 2.6; p = 0.01) and a lower value of the refill parameter β (β [1/s]: 0.62 ± 0.34 vs. 1.09 ± 0.58; p = 0.01) in ischemic compared with normal brain tissue, whereas there were no differences of the parameters A and Axβ. At follow-up, the delay of rt-TTP was reversible once recanalization of an underlying MCA obstruction was demonstrated: rt-TTP [s], 13.09 ± 3.21 at 24 h versus 10.95 ± 1.5 at 72-96 h (p = 0.03). Correspondingly, β showed a higher slope than at the first examination: β [1/s]: 0.55 ± 0.29 at 24 h versus 0.71 ± 0.27 at 72-96 h (p = 0.04). We conclude that real-time UPI can detect hemodynamic impairment in acute MCA occlusion and subsequent improvement following arterial recanalization. This offers the chance for bedside monitoring of the hemodynamic compromise (e.g. during therapeutic interventions such as systemic thrombolysis).

  2. Pressure and oxygen debt on bypass - potential quality markers of perfusion?

    Science.gov (United States)

    Poullis, Mike; Palmer, K; Al-Rawi, O; Johnson, I; Ridgeway, T

    2012-05-01

    No markers of quality of perfusion pressure and oxygen delivery during cardiopulmonary bypass (CPB), to complement rewarming rate, maximum temperature on rewarming, lowest haematocrit, and blood glucose, exist. Using the electronic acquisition of blood pressure on bypass (JOCAP system), the percentage of time perfusion pressure was below 30, 40, 50, 60 and 70 mmHg, average deviance, confidence interval, median, mode, standard deviation, variance, and average, maximum and cumulative oxygen debt were calculated. Numerous different readouts of achievement of maintenance of constant pressure on bypass and oxygen debt are now easily achievable with perfusion electronic data management systems. Mean, median, and mode offer poor discrimination of pressure control during CPB. Percentage of time perfusion pressure was below 30, 40, 50, 60 and 70 mmHg, average deviance, confidence interval, and standard deviation all have discriminatory power, but need clinical correlation for their significance. A composite score involving non-pressure readouts (e.g. oxygen delivery, arterial and venous saturations, and flow rates) may need to be integrated into any perfusion quality marker. Assessment of adequacy of constant perfusion pressure and oxygen delivery may allow the scientific evaluation of pressure and oxygen delivery on bypass for patients to be compared accurately. Currently, in studies involving CPB, blood pressure targets are stated with no quantitative assessment of adequacy of achievement of these targets. Electronic data monitoring during cardiopulmonary bypass, when correlated with clinical outcome, may help to provide a marker of quality of perfusion pressure during CPB and may, indeed, allow patient-specific perfusion pressure strategies to be developed.

  3. Cerebral perfusion reserve in carotid stenosis: Prognostic role in surgical and rheological therapy

    Energy Technology Data Exchange (ETDEWEB)

    Ussov, W.; Shipulin, V.; Shvera, I. [and others

    1994-05-01

    The study was aimed to evaluate the usefulness of the quantitative cerebral perfusion reserve SPECT for the prognosis in patients with critical stenoses of the internal carotid arteries treated surgically or rheotherapeutically. 23 patients with angiographically verified mono (n=12) or bilateral (n=11) stenosis of the internal carotid artery for more than 75% and with recent (>30 days) minor stroke or TIA events in anamnesis were referred for the study. 6 age-matched healthy persons served as controls. In everybody the cerebral perfusion reserve was studied by using of the local cerebral blood volume to cerebral blood flow (rCBV/rCBF, sec) index using a double isotope technique which combined Tl-199 diethyidithiocarbamate (Tl-199-DDC) SPECT with Tc-99m red blood cells (Tc-99m-RBC) SPECT. 12 patients underwent carotid endartherectomy and 11 were treated rheotherapeutically by nonselective plasma substitution (5 times x 400 ml, >1800 nil in total). Patients were studied twicely: before and 10 days after the treatment, and then followed-up neurologically in the course of 1 year. Patients who had regional rCBV/rCBF index increased in the stenosed a.carotis int. - dependent region before treatment (normal value 5.2, sd 0.2 sec) have got it significantly decreased after intervention both in surgical group (from 7.1, sd 0.4 sec, down to 5.3, sd 0.3 sec, p<0.01 n=7) and in rheotherapeutical one (from 7.3, sd 0.5 sec, to 5.9, sd 0.4 sec, p<0.02 n=8). In everybody who expressed the rCBV/rCBF decreased below 5.6 sec after intervention there were no cerebrovascular ischemic events observed in the course of 12 months after carotid surgery and during 5 months in patients treated by plasmapheresis. We conclude that rCBV/rCBF SPECT index gives an independent prognostic information useful for both rheologic and surgical treatment of cerebrovascular disease; and that plasmapheresis suppress the short-term rise of cerebral ischemic events, which effect is predictable by SPECT.

  4. CT and MR perfusion can discriminate severe cerebral hypoperfusion from perfusion absence: evaluation of different commercial software packages by using digital phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Uwano, Ikuko; Kudo, Kohsuke; Sasaki, Makoto [Iwate Medical University, Advanced Medical Research Center, Morioka (Japan); Christensen, Soren [University of Melbourne, Royal Melbourne Hospital, Departments of Neurology and Radiology, Victoria (Australia); Oestergaard, Leif [Aarhus University Hospital, Department of Neuroradiology, Center for Functionally Integrative Neuroscience, DK, Aarhus C (Denmark); Ogasawara, Kuniaki; Ogawa, Akira [Iwate Medical University, Department of Neurosurgery, Morioka (Japan)

    2012-05-15

    Computed tomography perfusion (CTP) and magnetic resonance perfusion (MRP) are expected to be usable for ancillary tests of brain death by detection of complete absence of cerebral perfusion; however, the detection limit of hypoperfusion has not been determined. Hence, we examined whether commercial software can visualize very low cerebral blood flow (CBF) and cerebral blood volume (CBV) by creating and using digital phantoms. Digital phantoms simulating 0-4% of normal CBF (60 mL/100 g/min) and CBV (4 mL/100 g/min) were analyzed by ten software packages of CT and MRI manufacturers. Region-of-interest measurements were performed to determine whether there was a significant difference between areas of 0% and areas of 1-4% of normal flow. The CTP software detected hypoperfusion down to 2-3% in CBF and 2% in CBV, while the MRP software detected that of 1-3% in CBF and 1-4% in CBV, although the lower limits varied among software packages. CTP and MRP can detect the difference between profound hypoperfusion of <5% from that of 0% in digital phantoms, suggesting their potential efficacy for assessing brain death. (orig.)

  5. Methodological NMR imaging developments to measure cerebral perfusion; Developpements methodologiques en IRM pour la mesure de perfusion cerebrale

    Energy Technology Data Exchange (ETDEWEB)

    Pannetier, N.

    2010-12-15

    This work focuses on acquisition techniques and physiological models that allow characterization of cerebral perfusion by MRI. The arterial input function (AIF), on which many models are based, is measured by a technique of optical imaging at the carotid artery in rats. The reproducibility and repeatability of the AIF are discussed and a model function is proposed. Then we compare two techniques for measuring the vessel size index (VSI) in rats bearing a glioma. The reference technique, using a USPIO contrast agent (CA), faces the dynamic approach that estimates this parameter during the passage of a bolus of Gd. This last technique has the advantage of being used clinically. The results obtained at 4.7 T by both approaches are similar and use of VSI in clinical protocols is strongly encouraged at high field. The mechanisms involved (R1 and R2* relaxivities) were then studied using a multi gradient -echoes approach. A multi-echoes spiral sequence is developed and a method that allows the refocusing between each echo is presented. This sequence is used to characterize the impact of R1 effects during the passage of two successive injections of Gd. Finally, we developed a tool for simulating the NMR signal on a 2D geometry taking into account the permeability of the BBB and the CA diffusion in the interstitial space. At short TE, the effect of diffusion on the signal is negligible. In contrast, the effects of diffusion and permeability may be separated at long echo time. Finally we show that during the extravasation of the CA, the local magnetic field homogenization due to the decrease of the magnetic susceptibility difference at vascular interfaces is quickly balanced by the perturbations induced by the increase of the magnetic susceptibility difference at the cellular interfaces in the extravascular compartment. (author)

  6. Brain volume perfusion CT performed with 128-detector row CT system in patients with cerebral gliomas: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Xyda, Argyro [University Hospital of Goettingen, Department of Neuroradiology, Georg-August University, Goettingen (Germany); University Hospital of Heraklion, Department of Radiology, Crete (Greece); Haberland, Ulrike; Klotz, Ernst [Computed Tomography, Siemens AG Healthcare Sector, Forchheim (Germany); Bock, Hans Christoph [University Hospital of Goettingen, Department of Neurosurgery, Georg-August University, Goettingen (Germany); Jung, Klaus [University Hospital of Goettingen, Department of Medical Statistics, Georg-August University, Goettingen (Germany); Knauth, Michael; Schramm, Ramona; Psychogios, Marios Nikos; Schramm, Peter [University Hospital of Goettingen, Department of Neuroradiology, Georg-August University, Goettingen (Germany); Erb, Gunter [Bracco Imaging Deutschland GmbH, Konstanz (Germany)

    2011-09-15

    Validation of the feasibility and efficacy of volume perfusion computed tomography (VPCT) in the preoperative assessment of cerebral gliomas by applying a 128-slice CT covering the entire tumour. Forty-six patients (25 men, 21 women; mean age 52.8 years) with cerebral gliomas were evaluated with VPCT. Two readers independently evaluated VPCT data, drawing volumes of interest (VOIs) around the tumour according to maximum intensity projection volumes, which were mapped automatically onto the cerebral blood volume (CBV), flow (CBF) and permeability (Ktrans) perfusion datasets. As control, a second VOI was placed in the contralateral healthy cortex. Correlation among perfusion parameters, tumour grade, hemisphere and VOIs was assessed. The diagnostic power of perfusion parameters was analysed by receiver operating characteristics curve analyses. VPCT was feasible in the assessment of the entire tumour extent. Mean values of Ktrans, CBV, CBF in high-grade gliomas were significantly higher compared with low-grade (p < 0.01). Ktrans demonstrated the highest diagnostic (97% sensitivity), positive (100%) and negative (94%) prognostic values. VPCT was feasible in all subjects. All areas of different perfusion characteristics are depicted and quantified in colour-coded 3D maps. The derived parameters correlate well with tumour histopathology, differentiating low- from high-grade gliomas. (orig.)

  7. Acute and chronic head-down tail suspension diminishes cerebral perfusion in rats

    Science.gov (United States)

    Wilkerson, M. Keith; Colleran, Patrick N.; Delp, Michael D.

    2002-01-01

    The purpose of this study was to test the hypothesis that regional brain blood flow and vascular resistance are altered by acute and chronic head-down tail suspension (HDT). Regional cerebral blood flow, arterial pressure, heart rate, and vascular resistance were measured in a group of control rats during normal standing and following 10 min of HDT and in two other groups of rats after 7 and 28 days of HDT. Heart rate was not different among conditions, whereas mean arterial pressure was elevated at 10 min of HDT relative to the other conditions. Total brain blood flow was reduced from that during standing by 48, 24, and 27% following 10 min and 7 and 28 days of HDT, respectively. Regional blood flows to all cerebral tissues and the eyes were reduced with 10 min of HDT and remained lower in the eye, olfactory bulbs, left and right cerebrum, thalamic region, and the midbrain with 7 and 28 days of HDT. Total brain vascular resistance was 116, 44, and 38% greater following 10 min and 7 and 28 days of HDT, respectively, relative to that during control standing. Vascular resistance was elevated in all cerebral regions with 10 min of HDT and remained higher than control levels in most brain regions. These results demonstrate that HDT results in chronic elevations in total and regional cerebral vascular resistance, and this may be the underlying stimulus for the HDT-induced smooth muscle hypertrophy of cerebral resistance arteries.

  8. Technetium-99m HM-PAO-SPECT study of regional cerebral perfusion in early Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Perani, D.; Di Piero, V.; Vallar, G.; Cappa, S.; Messa, C.; Bottini, G.; Berti, A.; Passafiume, D.; Scarlato, G.; Gerundini, P.

    1988-09-01

    Regional cerebral perfusion was evaluated by single photon emission computed tomography (SPECT) using technetium-99m hexamethylpropyleneamine oxime ((/sup 99m/Tc)HM-PAO) in sixteen patients with Alzheimer's disease (AD) in early clinical phase and in 16 healthy elderly controls. In all patients transmission computed tomography (TCT) and/or magnetic resonance imaging (MRI) did not show focal brain abnormalities. Relative to normal subjects, AD patients showed significant reductions in cortical/cerebellar activity ratio: cortical perfusion was globally depressed with the largest reductions in frontal and posterior temporo-parietal cortices. Asymmetries of relative perfusion between cerebral hemispheres were also demonstrated when language was affected or visuospatial functions were unevenly impaired. In patients with early AD, SPECT provides functional information to be compared with clinical and psychometric data.

  9. Skin perfusion pressure on the legs measured as the external pressure required for skin reddening after blanching

    DEFF Research Database (Denmark)

    Holstein, P; Nielsen, P.E.; Lund, P

    1980-01-01

    The skin perfusion on the calf was measured photo-electrically and by isotope washout technique using external counter pressure by a blood pressure cuff. By the photocell the skin blanching threshold external pressure (BTEP) was recorded on histamine flared red skin. By isotope washout technique......Hg (SD 8.7). As compared to the intra-arterial blood pressure the BTEP was found to lie close to the mean blood pressure in normal subjects as well as in hypertensive subjects. The present data indicate that the skin perfusion pressure on the legs can be measured by the rapid photo-electric technique...

  10. Mapping the dynamics of brain perfusion using functional ultrasound in a rat model of transient middle cerebral artery occlusion.

    Science.gov (United States)

    Brunner, Clément; Isabel, Clothilde; Martin, Abraham; Dussaux, Clara; Savoye, Anne; Emmrich, Julius; Montaldo, Gabriel; Mas, Jean-Louis; Baron, Jean-Claude; Urban, Alan

    2017-01-01

    Following middle cerebral artery occlusion, tissue outcome ranges from normal to infarcted depending on depth and duration of hypoperfusion as well as occurrence and efficiency of reperfusion. However, the precise time course of these changes in relation to tissue and behavioral outcome remains unsettled. To address these issues, a three-dimensional wide field-of-view and real-time quantitative functional imaging technique able to map perfusion in the rodent brain would be desirable. Here, we applied functional ultrasound imaging, a novel approach to map relative cerebral blood volume without contrast agent, in a rat model of brief proximal transient middle cerebral artery occlusion to assess perfusion in penetrating arterioles and venules acutely and over six days thanks to a thinned-skull preparation. Functional ultrasound imaging efficiently mapped the acute changes in relative cerebral blood volume during occlusion and following reperfusion with high spatial resolution (100 µm), notably documenting marked focal decreases during occlusion, and was able to chart the fine dynamics of tissue reperfusion (rate: one frame/5 s) in the individual rat. No behavioral and only mild post-mortem immunofluorescence changes were observed. Our study suggests functional ultrasound is a particularly well-adapted imaging technique to study cerebral perfusion in acute experimental stroke longitudinally from the hyper-acute up to the chronic stage in the same subject.

  11. Different CT perfusion algorithms in the detection of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Cremers, Charlotte H.P. [University Medical Center Utrecht, Department of Neurology and Neurosurgery, Room G03.232, Brain Center Rudolf Magnus Department of Neurology and Neurosurgery, PO Box 85500, Utrecht (Netherlands); University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Dankbaar, Jan Willem; Bennink, Edwin; Velthuis, Birgitta K.; Schaaf, Irene C. van der [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Vergouwen, Mervyn D.I.; Rinkel, Gabriel J.E. [University Medical Center Utrecht, Department of Neurology and Neurosurgery, Room G03.232, Brain Center Rudolf Magnus Department of Neurology and Neurosurgery, PO Box 85500, Utrecht (Netherlands); Vos, Pieter C. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands)

    2015-05-01

    Tracer delay-sensitive perfusion algorithms in CT perfusion (CTP) result in an overestimation of the extent of ischemia in thromboembolic stroke. In diagnosing delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH), delayed arrival of contrast due to vasospasm may also overestimate the extent of ischemia. We investigated the diagnostic accuracy of tracer delay-sensitive and tracer delay-insensitive algorithms for detecting DCI. From a prospectively collected series of aSAH patients admitted between 2007-2011, we included patients with any clinical deterioration other than rebleeding within 21 days after SAH who underwent NCCT/CTP/CTA imaging. Causes of clinical deterioration were categorized into DCI and no DCI. CTP maps were calculated with tracer delay-sensitive and tracer delay-insensitive algorithms and were visually assessed for the presence of perfusion deficits by two independent observers with different levels of experience. The diagnostic value of both algorithms was calculated for both observers. Seventy-one patients were included. For the experienced observer, the positive predictive values (PPVs) were 0.67 for the delay-sensitive and 0.66 for the delay-insensitive algorithm, and the negative predictive values (NPVs) were 0.73 and 0.74. For the less experienced observer, PPVs were 0.60 for both algorithms, and NPVs were 0.66 for the delay-sensitive and 0.63 for the delay-insensitive algorithm. Test characteristics are comparable for tracer delay-sensitive and tracer delay-insensitive algorithms for the visual assessment of CTP in diagnosing DCI. This indicates that both algorithms can be used for this purpose. (orig.)

  12. Assessment of Hyperperfusion by Brain Perfusion SPECT in Transient Neurological Deterioration after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis Surgery

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Won; Kim, Yu Kyeong; Lee, Sang Mi; Eo, Jae Sun; Oh, Chang Wan; Lee, Won Woo; Paeng, Jin Chul; Kim, Sang Eun [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2008-08-15

    Transient neurological deterioration (TND) is one of the complications after extracranial-intracranial bypass surgery, and it has been assumed to be caused by postoperative transient hyperperfusion. This study was performed to evaluate the relationship between TND and preoperative and postoperative cerebral perfusion status on brain perfusion SPECT following superficial temporal artery.middle cerebral artery (STA-MCA) anastomosis surgery. A total of 60 STA-MCA anastomosis surgeries of 56 patients (mean age: 50{+-}16 yrs; M:F=29:27; atherosclerotic disease: 33, moyamoya disease: 27) which were done between September 2003 and July 2006 were enrolled. The resting cerebral perfusion and cerebral vascular reserve (CVR) after acetazolamide challenge were measured before and 10 days after surgery using 99mTc-ethylcysteinate dimer (ECD) SPECT. Moreover, the cerebral perfusion was measured on the third postoperative day. With the use of the statistical parametric mapping and probabilistic brain atlas, the counts for the middle cerebral artery (MCA) territory were calculated for each image, and statistical analyses were performed. In 6 of 60 cases (10%), TND occurred after surgery. In all patients, the preoperative cerebral perfusion of affected MCA territory was significantly lower than that of contralateral side (p=0.002). The cerebral perfusion on the third and tenth day after surgery was significantly higher than preoperative cerebral perfusion (p=0.001, p=0.02). In TND patients, basal cerebral perfusion and CVR on preoperative SPECT were significantly lower than those of non-TND patients (p=0.01, p=0.05). Further, the increases in cerebral perfusion on the third day after surgery were significant higher than those in other patients (p=0.008). In patients with TND, the cerebral perfusion ratio of affected side to contralateral side on third postoperative day was significantly higher than that of other patients (p=0.002). However, there was no significant difference of

  13. Toward fully automated processing of dynamic susceptibility contrast perfusion MRI for acute ischemic cerebral stroke.

    Science.gov (United States)

    Kim, Jinsuh; Leira, Enrique C; Callison, Richard C; Ludwig, Bryan; Moritani, Toshio; Magnotta, Vincent A; Madsen, Mark T

    2010-05-01

    We developed fully automated software for dynamic susceptibility contrast (DSC) MR perfusion-weighted imaging (PWI) to efficiently and reliably derive critical hemodynamic information for acute stroke treatment decisions. Brain MR PWI was performed in 80 consecutive patients with acute nonlacunar ischemic stroke within 24h after onset of symptom from January 2008 to August 2009. These studies were automatically processed to generate hemodynamic parameters that included cerebral blood flow and cerebral blood volume, and the mean transit time (MTT). To develop reliable software for PWI analysis, we used computationally robust algorithms including the piecewise continuous regression method to determine bolus arrival time (BAT), log-linear curve fitting, arrival time independent deconvolution method and sophisticated motion correction methods. An optimal arterial input function (AIF) search algorithm using a new artery-likelihood metric was also developed. Anatomical locations of the automatically determined AIF were reviewed and validated. The automatically computed BAT values were statistically compared with estimated BAT by a single observer. In addition, gamma-variate curve-fitting errors of AIF and inter-subject variability of AIFs were analyzed. Lastly, two observes independently assessed the quality and area of hypoperfusion mismatched with restricted diffusion area from motion corrected MTT maps and compared that with time-to-peak (TTP) maps using the standard approach. The AIF was identified within an arterial branch and enhanced areas of perfusion deficit were visualized in all evaluated cases. Total processing time was 10.9+/-2.5s (mean+/-s.d.) without motion correction and 267+/-80s (mean+/-s.d.) with motion correction on a standard personal computer. The MTT map produced with our software adequately estimated brain areas with perfusion deficit and was significantly less affected by random noise of the PWI when compared with the TTP map. Results of image

  14. Correspondence of CT perfusion imaging to pathological manifestations in rabbit models of hyperacute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Mingwu Lou; Yi Fan; Lizhong Jia; Weidong Hu; Yan Teng; Guangfu Yang

    2007-01-01

    BACKGROUND: Could the infarction be diagnosed quickly and accurately at the acute stage by CT perfusion imaging (CTPI) technology? Whether the images of CTPI will correspond with the pathological changes or not? All the questions need to be solved by experimental and clinical studies.OBJECTIVE: To reveal the rules of perfusion map changes and guide the early diagnosis of hyperacute cerebral infarction by analyzing the correlation of CTPI with pathological manifestations for hyperacute cerebral infarction.DESIGN: A randomized controlled animal experiment.SETTING: Experimental Center of Medical Radiology, Longgang Central Hospital of Shenzhen City.MATERIALS: Forty-two adult New Zealand rabbits of (2.6±0.5) kg, either male or female, were randomly divided into experimental group (n =36) and control group (n =6). Six rabbits in the experimental group were observed after ischemia for 0.5, 1, 2, 3, 4 and 6 hours respectively, and 1 rabbit in the control group was observed at each corresponding time point.METHODS: The experiments were carded out in the Experimental Center of Medical Radiology,Longgang Central Hospital of Shenzhen City from March 2003 to July 2004, Rabbit models of cerebral scanned at 0.5, 1, 2, 3, 4 and 6 hours after ischemia respectively. The dynamic CT scan slice was 13 mm from the anterior edge of the frontal cortex, and six fake color functional images were obtained, including cerebral blood flow map (CBF map), cerebral blood volume map (CBV map), peak to enhancement map (PE map),flow without vessels map, time to peak map (TP map), time to start map (TS map). The manifestations and (ROI) were drawn separately on the CBF map, CBV map, TP map and TS map. The blood flow parameters of focal and contralateral cerebral tissues could be obtained to calculate relative cerebral blood flow (rCBF,rCBF=focal CBF/contralateral CBF), relative cerebral blood volume (rCBV, rCBV= focal CBV/contralateral CBV), a relative time to peak (rTP, rTP= focal TP

  15. Iofetamine hydrochloride I 123: a new radiopharmaceutical for cerebral perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Druckenbrod, R.W.; Williams, C.C.; Gelfand, M.J.

    1989-01-01

    Iofetamine hydrochloride I-123 permits cerebral blood perfusion imaging with single photon emission computed tomography (SPECT). SPECT is more widely available than positron emission tomography, and complements anatomic visualization with X-ray computed tomography (CT) or magnetic resonance imaging. Iofetamine is an amphetamine analog that is rapidly taken up by the lungs, then redistributed principally to the liver and brain. The precise mechanism of localization has not been determined, but is believed to result from nonspecific receptor binding. Brain uptake peaks at 30 minutes postinjection and remains relatively constant through 60 minutes. The drug is metabolized and excreted in the urine, with negligible activity remaining at 48 hours. When compared with CT in stroke patients, visualization may be performed sooner after symptom onset and a larger zone of involvement may be evident with iofetamine. Localization of seizure foci and diagnosis of Alzheimer's disease may also be possible. As CT has revolutionized noninvasive imaging of brain anatomy, SPECT with iofetamine permits routine cerebral blood flow imaging. 36 references.

  16. Effects of ovariohysterectomy on intra-abdominal pressure and abdominal perfusion pressure in cats.

    Science.gov (United States)

    Bosch, L; Rivera del Álamo, M M; Andaluz, A; Monreal, L; Torrente, C; García-Arnas, F; Fresno, L

    2012-12-15

    Intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) have shown clinical relevance in monitoring critically ill human beings submitted to abdominal surgery. Only a few studies have been performed in veterinary medicine. The aim of this study was to assess how pregnancy and abdominal surgery may affect IAP and APP in healthy cats. For this purpose, pregnant (n=10) and non-pregnant (n=11) queens undergoing elective spaying, and tomcats (n=20, used as controls) presented for neutering by scrotal orchidectomy were included in the study. IAP, mean arterial blood pressure (MAP), APP, heart rate and rectal temperature (RT) were determined before, immediately after, and four hours after surgery. IAP increased significantly immediately after abdominal surgery in both female groups when compared with baseline (PPregnancy did not seem to affect IAP in this population of cats, possibly due to subjects being in early stages of pregnancy.

  17. Quantitative Measurement of Cerebral Perfusion with Intravoxel Incoherent Motion in Acute Ischemia Stroke: Initial Clinical Experience

    Institute of Scientific and Technical Information of China (English)

    Li-Bao Hu; Nan Hong; Wen-Zhen Zhu

    2015-01-01

    Background:Intravoxel incoherent motion (IVIM) has the potential to provide both diffusion and perfusion information without an exogenous contrast agent,its application for the brain is promising,however,feasibility studies on this are relatively scarce.The aim of this study is to assess the feasibility of IVIM perfusion in patients with acute ischemic stroke (AIS).Methods:Patients with suspected AIS were examined by magnetic resonance imaging within 24 h of symptom onset.Fifteen patients (mean age was 68.7 ± 8.0 years) who underwent arterial spin labeling (ASL) and diffusion-weighted imaging (DWI) were identified as having AIS with ischemic penumbra were enrolled,where ischemic penumbra referred to the mismatch areas of ASL and DWI.Eleven different b-values were applied in the biexponential model.Regions of interest were selected in ischemic penumbras and contralateral normal brain regions.Fast apparent diffusion coefficients (ADCs) and ASL cerebral blood flow (CBF) were measured.The paired t-test was applied to compare ASL CBF,fast ADC,and slow ADC measurements between ischemic penumbras and contralateral normal brain regions.Linear regression and Pearson's correlation were used to evaluate the correlations among quantitative results.Results:The fast ADCs and ASL CBFs of ischemic penumbras were significantly lower than those of the contralateral normal brain regions (1.93 ± 0.78 μm2/ms vs.3.97 ± 2.49 μm2/ms,P =0.007;13.5 ± 4.5 ml· 100 g-1 ·min-1 vs.29.1 ± 12.7 ml·100 g-1 ·min-1,P < 0.001,respectively).No significant difference was observed in slow ADCs between ischemic penumbras and contralateral normal brain regions (0.203 ± 0.090 μm2/ms vs.0.198 ± 0.100 μm2/ms,P =0.451).Compared with contralateral normal brain regions,both CBFs and fast ADCs decreased in ischemic penumbras while slow ADCs remained the same.A significant correlation was detected between fast ADCs and ASL CBFs (r =0.416,P < 0.05).No statistically significant correlation was

  18. Prediction of cerebral hyperperfusion syndrome after carotid artery stenting by CT perfusion imaging with acetazolamide challenge

    Energy Technology Data Exchange (ETDEWEB)

    Yoshie, Tomohide; Ueda, Toshihiro; Takada, Tatsuro; Nogoshi, Shinji; Fukano, Takayuki [St. Marianna University Toyoko Hospital, Department of Strokology, Stroke Center, Kawasaki (Japan); Hasegawa, Yasuhiro [St. Marianna University School of Medicine, Department of Internal Medicine, Division of Neurology, Kawasaki (Japan)

    2016-03-15

    Cerebral hyperperfusion syndrome (HPS) is an uncommon but serious complication of carotid artery stenting (CAS). The purpose of this study was to investigate the efficacy of CT perfusion imaging (CTP) with acetazolamide challenge to identify patients at risk for HPS after CAS. We retrospectively analyzed 113 patients who underwent CTP with rest and acetazolamide challenge before CAS. CTP maps were assessed for absolute and relative cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and change of each parameter before and after acetazolamide challenge. Patients were divided into two groups according to the HPS after the CAS. Receiver-operating characteristic (ROC) curve analysis was performed to determine the most accurate CTP parameter for the prediction of HPS. Nine of 113 patients had HPS. There were significant differences for absolute and relative values of resting CBF (p = 0.001 and p = 0.026), resting MTT (p < 0.001 and p = 0.004), post-acetazolamide CBF (p < 0.001 and p = 0.001), post-acetazolamide MTT (p < 0.001 and p = 0.002), and %changes of CBF (p = 0.009) between the HPS and non-HPS groups. ROC curve analysis showed that the CTP parameters with the maximal area under the receiver-operating characteristic curve (AUC) for HPS was the absolute value of post-acetazolamide MTT (AUC 0.909) and the absolute value of resting MTT (AUC 0.896). Pretreatment CTP with acetazolamide challenge could identify patients at risk for HPS after CAS. Although the CTP parameter that most accurately identified patients at risk for HPS was the absolute value of post-acetazolamide MTT, resting MTT was sufficiently accurate. (orig.)

  19. Effect of large decompressive craniectomy combined with vascular reconstruction on cerebral perfusion in patients with severe brain injury

    Directory of Open Access Journals (Sweden)

    Liang-zhen HUANG

    2015-11-01

    Full Text Available Objective To compare the efficacies of large decompressive craniectomy combined with vascular reconstruction and traditional decompressive craniectomy in treatment of severe brain injury. Methods Forty-eight patients with severe brain injury, which was dominated by brain contusion to the frontoparietal lobes, admitted to our hospital from March 2012 to March 2014 were divided equally into experimental group and control group. The patients in the experimental group underwent large decompressive craniectomy combined with vascular reconstruction, and the patients in the control group received traditional decompressive craniectomy. The hemodynamic changes including cerebral blood flow (CBF, cerebral blood volume (CBV, mean transit time (MTT, time to peak (TTP and the ratios of these values (rCBF, rCBV, rMTT and rTTP on two sides were observed by CT perfusion imaging, and the Glasgow outcome score (GOS was analyzed 6 months after operation. Results The CBF and CBV scores in experimental group were higher than those in the control group at 1 week and 1 month after the operation (P0.05. The rate of satisfactory recovery (including good recovery and moderate disability was higher in the experimental group than in the control group, while the rate of poor recovery (including severe disability, vegetative state and death was lower in the experimental group than in the control group (P<0.05. Conclusion The large decompressive craniectomy combined with vascular reconstruction can not only decrease the intracranial pressure, but also recover the blood supply of brain, thus deserving the clinical application and popularization. DOI: 10.11855/j.issn.0577-7402.2015.11.15

  20. Patient Directed Perfusion Pressure on Bypass, an Analogy from Electrical Engineering—A New Concept

    Science.gov (United States)

    Warwick, Richard; Poole, Robert; Palmer, Kenneth; Johnson, Ian; Poullis, Michael

    2010-01-01

    Abstract: Organ ischemia, particularly mesenteric and renal, can occur despite a seemingly adequate perfusion flow and pressure during a period of cardiopulmonary bypass. The blood pressure to run bypass at remains a contentious issue. We present the concept that perfusion pressure during cardiopulmonary bypass should be patient specific, depending on an individual’s resting pre-procedural blood pressure. Four simulated arterial traces with variable morphology, but identical systolic and diastolic blood pressures, were analyzed to calculate the medical mean, arithmetic mean, and root mean square of the blood pressure tracing. Using the standard medical formula for calculation of mean blood pressure, you can potentially underestimate perfusion pressure by 12 mmHg in a normotensive subject. The root mean square pressure calculates the equivalent non pulsatile pressure that will deliver the same hydraulic power to the circulation as its pulsatile equivalent. Patient specific perfusion pressures, calculated via root mean square may potentially help reduce the incidence of organ ischemia during cardiopulmonary bypass. Clinical trials are needed to confirm or refute this concept. PMID:20437793

  1. Patient directed perfusion pressure on bypass, an analogy from electrical engineering--a new concept.

    Science.gov (United States)

    Warwick, Richard; Poole, Robert; Palmer, Kenneth; Johnson, Ian; Poullis, Michael

    2010-03-01

    Organ ischemia, particularly mesenteric and renal, can occur despite a seemingly adequate perfusion flow and pressure during a period of cardiopulmonary bypass. The blood pressure to run bypass at remains a contentious issue. We present the concept that perfusion pressure during cardiopulmonary bypass should be patient specific, depending on an individual's resting pre-procedural blood pressure. Four simulated arterial traces with variable morphology, but identical systolic and diastolic blood pressures, were analyzed to calculate the medical mean, arithmetic mean, and root mean square of the blood pressure tracing. Using the standard medical formula for calculation of mean blood pressure, you can potentially underestimate perfusion pressure by 12 mmHg in a normotensive subject. The root mean square pressure calculates the equivalent non pulsatile pressure that will deliver the same hydraulic power to the circulation as its pulsatile equivalent. Patient specific perfusion pressures, calculated via root mean square may potentially help reduce the incidence of organ ischemia during cardiopulmonary bypass. Clinical trials are needed to confirm or refute this concept.

  2. Similar cerebral protective effectiveness of antegrade and retrograde cerebral perfusion during deep hypothermic circulatory arrest in aortic surgery: a meta-analysis of 7023 patients.

    Science.gov (United States)

    Guo, Shasha; Sun, Yanhua; Ji, Bingyang; Liu, Jinping; Wang, Guyan; Zheng, Zhe

    2015-04-01

    In aortic arch surgery, deep hypothermic circulatory arrest (DHCA) combined with cerebral perfusion is employed worldwide as a routine practice. Even though antegrade cerebral perfusion (ACP) is more widely used than retrograde cerebral perfusion (RCP), the difference in benefit and risk between ACP and RCP during DHCA is uncertain. The purpose of this meta-analysis is to compare neurologic outcomes and early mortality between ACP and RCP in patients who underwent aortic surgery during DHCA. PubMed, EMBASE, and the Cochrane Library were searched using the key words "antegrade," "retrograde," "cerebral perfusion," "cardiopulmonary bypass," "extracorporeal circulation," and "cardiac surgery" for studies reporting on clinical endpoints including early mortality, stroke, temporary neurologic dysfunction (TND), and permanent neurologic dysfunction (PND) in aortic surgery requiring DHCA with ACP or RCP. Heterogeneity was analyzed with the Cochrane Q statistic and I(2) statistic. Publication bias was tested with Begg's funnel plot and Egger's test. Thirty-four studies were included in this meta-analysis, with 4262 patients undergoing DHCA + ACP and 2761 undergoing DHCA + RCP. The overall pooled relative risk for TND was 0.722 (95% CI = [0.579, 0.900]), and the z-score for overall effect was 2.9 (P = 0.004). There was low heterogeneity (I(2) = 18.7%). The analysis showed that patients undergoing DHCA + ACP had better outcomes than those undergoing DHCA + RCP in terms of TND, while there were no significant differences between groups in terms of PND, stroke, and early mortality. This meta-analysis indicates that DHCA + ACP has an advantage over DHCA + RCP in terms of TND, while the two methods show similar results in terms of PND, early mortality, and stroke.

  3. Effect of combined VEGF165/ SDF-1 gene therapy on vascular remodeling and blood perfusion in cerebral ischemia.

    Science.gov (United States)

    Hu, Guo-Jie; Feng, Yu-Gong; Lu, Wen-Peng; Li, Huan-Ting; Xie, Hong-Wei; Li, Shi-Fang

    2016-12-16

    OBJECTIVE Therapeutic neovascularization is a promising strategy for treating patients after an ischemic stroke; however, single-factor therapy has limitations. Stromal cell-derived factor 1 (SDF-1) and vascular endothelial growth factor (VEGF) proteins synergistically promote angiogenesis. In this study, the authors assessed the effect of combined gene therapy with VEGF165 and SDF-1 in a rat model of cerebral infarction. METHODS An adenoviral vector expressing VEGF165 and SDF-1 connected via an internal ribosome entry site was constructed (Ad- VEGF165-SDF-1). A rat model of middle cerebral artery occlusion (MCAO) was established; either Ad- VEGF165-SDF-1 or control adenovirus Ad- LacZ was stereotactically microinjected into the lateral ventricle of 80 rats 24 hours after MCAO. Coexpression and distribution of VEGF165 and SDF-1 were examined by reverse-transcription polymerase chain reaction, Western blotting, and immunofluorescence. The neurological severity score of each rat was measured on Days 3, 7, 14, 21, and 28 after MCAO. Angiogenesis and vascular remodeling were evaluated via bromodeoxyuridine and CD34 immunofluorescence labeling. Relative cerebral infarction volumes were determined by T2-weighted MRI and triphenyltetrazolium chloride staining. Cerebral blood flow, relative cerebral blood volume, and relative mean transmit time were assessed using perfusion-weighted MRI. RESULTS The Ad- VEGF165-SDF-1 vector mediated coexpression of VEGF165 and SDF-1 in multiple sites around the ischemic core, including the cortex, corpus striatum, and hippocampal granular layer. Coexpression of VEGF165 and SDF-1 improved neural function, reduced cerebral infarction volume, increased microvascular density and promoted angiogenesis in the ischemic penumbra, and improved cerebral blood flow and perfusion. CONCLUSIONS Combined VEGF165 and SDF-1 gene therapy represents a potential strategy for improving vascular remodeling and recovery of neural function after cerebral

  4. Substance P content in the cerebrospinal fluid and fluid perfusing cerebral ventricles during elicitation and inhibition of trigemino-hypoglossal reflex in rats.

    Science.gov (United States)

    Zubrzycka, Maria; Janecka, Anna

    2002-06-21

    The aim of this study was to establish whether tooth pulp and periaqueductal central gray (PAG) stimulation affects the release of substance P (SP) into the fluid perfusing the cerebral ventricles in rats. The content of substance P in the cerebrospinal fluid and fluid perfusing cerebral ventricles was determined during incisor pulp stimulation with electrical impulses inducing nociceptive trigemino-hypoglossal reflex and then during inhibition of the reflex by stimulation of PAG. Perfusion of the cerebral ventricles was carried out using artificial cerebrospinal fluid (aCSF). SP-like immunoreactivity (SP-LI) was determined in the samples by radioimmunoassay. Samples were collected in four groups: first group-cerebrospinal fluid (CSF); second group-aCSF perfusates without stimulation; third group-aCSF perfusates during incisor pulp stimulation; fourth group-aCSF perfusates during incisor pulp stimulation and simultaneous inhibition of trigemino-hypoglossal reflex by PAG stimulation. It was shown that incisor pulp stimulation led to the increased release of SP-LI into the fluid perfusing cerebral ventricles. Stimulation of PAG reduced the release of SP-LI into the cerebro-ventricular system to the values obtained before the tooth pulp stimulation. The results indicate that PAG significantly inhibits the release of SP-LI into the rat cerebral ventricular system and may be involved in the inhibition of trigemino-hypoglossal reflex.

  5. Differential Features of Cerebral Perfusion in Dementia with Lewy Bodies Compared to Alzheimer's Dementia using SPM Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Do Young; Park, Kyung Won; Kim, Jae Woo [College of Medicine, Univ. of Donga, Busan (Korea, Republic of)

    2003-07-01

    Alzheimer's dementia (AD) and dementia with Lewy bodies (DLB) are most common cause of dementia in elderly people. Clinical distinction in some cases of DLB from AD may be difficult as symptom profiles overlap. Some neuropathologic overlap is also seen as beta-amyloidosis and senile plaques can be found in both disease. Both disease also share severe acetylcholine depletion. We evaluated the differences of brain perfusion between DLB and AD using statistical parametric mapping analysis. Twelve DLB (mean age ; 68.8{+-}8.3 years, K-MMSE ; 17.3{+-}6.1) and 51 AD patients (mean age ; 71.4{+-}7.2 years, K-MMSE ; 16.7{+-}4.5), which were matched for age and severity of dementia, participated in this study. Tc-99m HMPAO SPECT was performed for measuring regional cerebral blood flow. Statistical parametric mapping (SPM99) software was used for automatic and objective approach to analyze SPECT image data. The SPECT data of the patients with DLB were compared to patients with AD. Comparison of the two dementia groups (uncorrected p<0.01) revealed significant hypoperfusion in both occipital (both middle occipital gyrus, Rt B no. 18 and Lt cuneus), both parietal (Lt parietal precuneus, Lt B no. 39, Lt inferior parietal lobule and Rt supramarginal gyrus) lobes in DLB compared with AD. Significant hyperperfusion was noted in Rt frontal (sup. frontal gyrus, B no.10, middle frontal gyrus, B no. 9, B no. 11, inf. frontal gyrus), Rt putamen, Lt ant. cingulate gyrus (B no. 24), both cerebellar post. lobe (Lt tuber, Lt declive, Lt tonsil, Rt declive) in DLB compared with AD. We found a significant differences in the cerebral perfusion pattern between DLB and AD. Differential feature of cerebral perfusion in DLB was both occipital hypoperfusion and preserved Rt frontal perfusion compared to AD. Therefore in difficult case of clinical an neuro pathologic diagnosis, brain perfusion SPECT with SPM analysis may be helpful to differentiate DLB from AD.

  6. Accuracy of CT cerebral perfusion in predicting infarct in the emergency department: lesion characterization on CT perfusion based on commercially available software.

    Science.gov (United States)

    Ho, Chang Y; Hussain, Sajjad; Alam, Tariq; Ahmad, Iftikhar; Wu, Isaac C; O'Neill, Darren P

    2013-06-01

    This study aims to assess the diagnostic accuracy of a single vendor commercially available CT perfusion (CTP) software in predicting stroke. A retrospective analysis on patients presenting with stroke-like symptoms within 6 h with CTP and diffusion-weighted imaging (DWI) was performed. Lesion maps, which overlays areas of computer-detected abnormally elevated mean transit time (MTT) and decreased cerebral blood volume (CBV), were assessed from a commercially available software package and compared to qualitative interpretation of color maps. Using DWI as the gold standard, parameters of diagnostic accuracy were calculated. Point biserial correlation was performed to assess for relationship of lesion size to a true positive result. Sixty-five patients (41 females and 24 males, age range 22-92 years, mean 57) were included in the study. Twenty-two (34 %) had infarcts on DWI. Sensitivity (83 vs. 70 %), specificity (21 vs. 69 %), negative predictive value (77 vs. 84 %), and positive predictive value (29 vs. 50 %) for lesion maps were contrasted to qualitative interpretation of perfusion color maps, respectively. By using the lesion maps to exclude lesions detected qualitatively on color maps, specificity improved (80 %). Point biserial correlation for computer-generated lesions (R pb = 0.46, p perfusion color map assessment, the lesion maps can help improve specificity.

  7. Quantitative cerebral perfusion assessment using microscope-integrated analysis of intraoperative indocyanine green fluorescence angiography versus positron emission tomography in superficial temporal artery to middle cerebral artery anastomosis

    Directory of Open Access Journals (Sweden)

    Shinya Kobayashi

    2014-01-01

    Full Text Available Background: Intraoperative qualitative indocyanine green (ICG angiography has been used in cerebrovascular surgery. Hyperperfusion may lead to neurological complications after superficial temporal artery to middle cerebral artery (STA-MCA anastomosis. The purpose of this study is to quantitatively evaluate intraoperative cerebral perfusion using microscope-integrated dynamic ICG fluorescence analysis, and to assess whether this value predicts hyperperfusion syndrome (HPS after STA-MCA anastomosis. Methods: Ten patients undergoing STA-MCA anastomosis due to unilateral major cerebral artery occlusive disease were included. Ten patients with normal cerebral perfusion served as controls. The ICG transit curve from six regions of interest (ROIs on the cortex, corresponding to ROIs on positron emission tomography (PET study, was recorded. Maximum intensity (I MAX , cerebral blood flow index (CBFi, rise time (RT, and time to peak (TTP were evaluated. Results: RT/TTP, but not I MAX or CBFi, could differentiate between control and study subjects. RT/TTP correlated (|r| = 0.534-0.807; P < 0.01 with mean transit time (MTT/MTT ratio in the ipsilateral to contralateral hemisphere by PET study. Bland-Altman analysis showed a wide limit of agreement between RT and MTT and between TTP and MTT. The ratio of RT before and after bypass procedures was significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.60 ± 0.032 and 0.80 ± 0.056, respectively; P = 0.017. The ratio of TTP was also significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.64 ± 0.081 and 0.85 ± 0.095, respectively; P = 0.017. Conclusions: Time-dependent intraoperative parameters from the ICG transit curve provide quantitative information regarding cerebral circulation time with quality and utility comparable to information obtained by PET. These parameters may help predict the occurrence of postoperative

  8. Quantitative Susceptibility Mapping and Dynamic Contrast Enhanced Quantitative Perfusion in Cerebral Cavernous Angiomas

    Science.gov (United States)

    Mikati, Abdul Ghani; Tan, Huan; Shenkar, Robert; Li, Luying; Zhang, Lingjiao; Guo, Xiaodong; Shi, Changbin; Liu, Tian; Wang, Yi; Shah, Akash; Edelman, Robert; Christoforidis, Gregory; Awad, Issam

    2015-01-01

    Background Hyperpermeability and iron deposition are two central pathophysiological phenomena in human cerebral cavernous malformation (CCM) disease. Here we used two novel magnetic resonance imaging (MRI) techniques to establish a relationship between these phenomena. Methods Subjects with CCM disease (4 sporadic and 18 familial) underwent MRI imaging using the Dynamic Contrast Enhanced Quantitative Perfusion (DCEQP) and Quantitative Susceptibility Mapping (QSM) techniques that measure hemodynamic factors of vessel leak and iron deposition respectively, previously demonstrated in CCM disease. Regions of interest encompassing the CCM lesions were analyzed using these techniques Results Susceptibility measured by QSM was positively correlated with permeability of lesions measured using DCEQP (r=0.49, p=<0.0001). The correlation was not affected by factors including familial predisposition, lesion volume, the contrast agent and the use of statin medication. Susceptibility was correlated with lesional blood volume (r=0.4, p=0.0001), but not with lesional blood flow. Conclusion The correlation between QSM and DCEQP suggests that the phenomena of permeability and iron deposition are related in CCM; hence “more leaky lesions” also manifest a more cumulative iron burden. These techniques might be used as biomarkers to monitor the course of this disease and the effect of therapy. PMID:24302484

  9. Cerebral perfusion and automated individual analysis using SPECT among an obsessive-compulsive population

    Directory of Open Access Journals (Sweden)

    Euclides Timóteo da Rocha

    2011-01-01

    Full Text Available OBJECTIVE: To make individual assessments using automated quantification methodology in order to screen for perfusion abnormalities in cerebral SPECT examinations among a sample of subjects with OCD. METHODS: Statistical parametric mapping (SPM was used to compare 26 brain SPECT images from patients with OCD individually with an image bank of 32 normal subjects, using the statistical threshold of p < 0.05 (corrected for multiple comparisons at the level of individual voxels or clusters. The maps were analyzed, and regions presenting voxels that remained above this threshold were sought. RESULTS: Six patients from a sample of 26 OCD images showed abnormalities at cluster or voxel level, considering the criteria described above, which represented 23.07%. However, seven images from the normal group of 32 were also indicated as cases of perfusional abnormality, representing 21.8% of the sample. CONCLUSION: The automated quantification method was not considered to be a useful tool for clinical practice, for analyses complementary to visual inspection.

  10. Dynamics of cerebral tissue injury and perfusion after temporary hypoxia-ischemia in the rat - Evidence for region-specific sensitivity and delayed damage

    NARCIS (Netherlands)

    Dijkhuizen, RM; Knollema, S; van der Worp, H. Bart; Ter Horst, GJ; De Wildt, DJ; van der Sprenkel, JWB; Tulleken, KAF; Nicolay, K

    1998-01-01

    Background and Purpose-Selective regional sensitivity and delayed damage in cerebral ischemia provide opportunities for directed and late therapy for stroke. Our aim was to characterize the spatial and temporal profile of ischemia-induced changes in cerebral perfusion and tissue status, with the use

  11. Is correction necessary when clinically determining quantitative cerebral perfusion parameters from multi-slice dynamic susceptibility contrast MR studies?

    Science.gov (United States)

    Salluzzi, M; Frayne, R; Smith, M R

    2006-01-21

    Several groups have modified the standard singular value decomposition (SVD) algorithm to produce delay-insensitive cerebral blood flow (CBF) estimates from dynamic susceptibility contrast (DSC) perfusion studies. However, new dependences of CBF estimates on bolus arrival times and slice position in multi-slice studies have been recently recognized. These conflicting findings can be reconciled by accounting for several experimental and algorithmic factors. Using simulation and clinical studies, the non-simultaneous measurement of arterial and tissue concentration curves (relative slice position) in a multi-slice study is shown to affect time-related perfusion parameters, e.g. arterial-tissue-delay measurements. However, the current clinical impact of relative slice position on amplitude-related perfusion parameters, e.g. CBF, can be expected to be small unless any of the following conditions are present individually or in combination: (a) high concentration curve signal-to-noise ratios, (b) small tissue mean transit times, (c) narrow arterial input functions or (d) low temporal resolution of the DSC image sequence. Recent improvements in magnetic resonance (MR) technology can easily be expected to lead to scenarios where these effects become increasingly important sources of inaccuracy for all perfusion parameter estimates. We show that using Fourier interpolated (high temporal resolution) residue functions reduces the systematic error of the perfusion parameters obtained from multi-slice studies.

  12. Is correction necessary when clinically determining quantitative cerebral perfusion parameters from multi-slice dynamic susceptibility contrast MR studies?

    Science.gov (United States)

    Salluzzi, M.; Frayne, R.; Smith, M. R.

    2006-01-01

    Several groups have modified the standard singular value decomposition (SVD) algorithm to produce delay-insensitive cerebral blood flow (CBF) estimates from dynamic susceptibility contrast (DSC) perfusion studies. However, new dependences of CBF estimates on bolus arrival times and slice position in multi-slice studies have been recently recognized. These conflicting findings can be reconciled by accounting for several experimental and algorithmic factors. Using simulation and clinical studies, the non-simultaneous measurement of arterial and tissue concentration curves (relative slice position) in a multi-slice study is shown to affect time-related perfusion parameters, e.g. arterial-tissue-delay measurements. However, the current clinical impact of relative slice position on amplitude-related perfusion parameters, e.g. CBF, can be expected to be small unless any of the following conditions are present individually or in combination: (a) high concentration curve signal-to-noise ratios, (b) small tissue mean transit times, (c) narrow arterial input functions or (d) low temporal resolution of the DSC image sequence. Recent improvements in magnetic resonance (MR) technology can easily be expected to lead to scenarios where these effects become increasingly important sources of inaccuracy for all perfusion parameter estimates. We show that using Fourier interpolated (high temporal resolution) residue functions reduces the systematic error of the perfusion parameters obtained from multi-slice studies. Preliminary results associated with this paper were presented at ISMRM 12th Scientific Meeting and Exhibition, Kyoto, Japan, 2004.

  13. Clinical Neuroimaging of cerebral ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawara, Jyoji [Nakamura Memorial Hospital, Sapporo (Japan)

    1999-06-01

    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.)

  14. Dose reduction in dynamic perfusion CT of the brain: effects of the scan frequency on measurements of cerebral blood flow, cerebral blood volume, and mean transit time

    Energy Technology Data Exchange (ETDEWEB)

    Wiesmann, Martin [University of Munich, Department of Neuroradiology, Muenchen (Germany); Klinikum der Universitaet Muenchen - Grosshadern, Abteilung fuer Neuroradiologie, Muenchen (Germany); Berg, Scott; Stoeckelhuber, B.M. [University of Luebeck, Department of Radiology, Luebeck (Germany); Bohner, G.; Klingebiel, R. [University Medicine Berlin, Department of Neuroradiology, Charite, Berlin (Germany); Schoepf, V.; Yousry, I.; Linn, J. [University of Munich, Department of Neuroradiology, Muenchen (Germany); Missler, U. [Evangelisches Krankenhaus Duisburg-Nord, Department of Neuroradiology, Duisburg (Germany)

    2008-12-15

    The influence of the frequency of computed tomography (CT) image acquistion on the diagnostic quality of dynamic perfusion CT (PCT) studies of the brain was investigated. Eight patients with clinically suspected acute ischemia of one hemisphere underwent PCT, performed on average 3.4 h after the onset of symptoms. Sixty consecutive images per slice were obtained with individual CT images obtained at a temporal resolution of two images per second. Eight additional data sets were reconstructed with temporal resolutions ranging from one image per second to one image per 5 s. Cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) measurements were performed in identical regions of interest. Two neuroradiologists evaluated the PCT images visually to identify areas of abnormal perfusion. Perfusion images created up to a temporal resolution of one image per 3 s were rated to be diagnostically equal to the original data. Even at one image per 4 s, all areas of infarction were identified. Quantitative differences of CBF, CBV and MTT measurements were {<=}10% up to one image per 3 s. For PCT of the brain, temporal resolution can be reduced to one image per 3 s without significant compromise in image quality. This significantly reduces the radiation dose of the patient. (orig.)

  15. Serial cerebral hemodynamic change after extracranial-intracranial (EC-IC) bypass surgery: evaluated by acetazolamide stress brain perfusion SPECT(acz-SPECT)

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Il Ki; Kim, Jae Seung; Ahn, Jae Sung; Im, Ki Chun; Kim, Euy Nyong; Mun, Dae Hyeog [Asan Medical Center, Seoul (Korea, Republic of)

    2005-07-01

    We evaluated serial cerebral hemodynamic changes after EC-IC bypass surgery in symptomatic pts with atherosclerotic occlusion of internal carotid (lCA) or mid-cerebral artery (MCA) using Acz-SPECT. 25 symptomatic pts (M/F 19/6, 53{+-}10 y) with ICA and MCA occlusion (16 uni - and 9 bilateral) prospectively underwent Acz-SPECT using Tc-99m ECD before and 1 week after EC-IC bypass surgery. Of these, 16 underwent additional f/u Acz-SPECT 5 mo later. Cerebral perfusion and perfusion reserve of MCA territory were evaluated visually and SPECT findings were classified into 4 groups: N/N; R/N; N/R; and R/R (perfusion/perfusion reserve: N = normal, R = reduced). For semiquantitative analysis, all SPECT images were normalized to MNI template and mean counts of MCA territory and cerebellum were obtained by AAL. Cerebral perfusion index (PI =C{sub region}/C{sub cere}) and perfusion reserve index (RI = (PI{sub Acz} - PI{sub basal}) /Pl{sub basal}) were calculated. Preop SPECT findings of ipsilateral MCA in 25 pts were R/N (4%), N/R (12%), and R/R (84% ). Early postop SPECT showed improvement of perfusion (26%) and/or reserve (68%) in ipsilateral MCA. Of 16 pts with 5mo f/u SPECT, 6 (38%) showed further improvement of perfusion or reserve. However, 4 (25%) showed aggravation of perfusion and one of these underwent revision surgery. Preop PI (1.1{+-}0.1) and RI (0.11{+-}0.07) of ipsilateral MCA were significantly lower than those of contralateral hemispheres (p<0.05). After surgery, PIs of bilateral MCA did not change at early postop period but improved in ipsilateral MCA at 5mo. Rls of ipsilateral MCA increased significantly (68%) at early postop period (P<0.001) and then did not changed. Cerebral perfusion and perfusion reserve changed with different manner during 5 mo after bypass surgery and perfusion reserve changed more dramatically than perfusion. Acz-SPECT is a feasible method for evaluating cerebral hemodynamic change after EC-IC bypass surgery.

  16. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    Science.gov (United States)

    Mendrik, Adriënne M.; Vonken, Evert-jan; van Ginneken, Bram; de Jong, Hugo W.; Riordan, Alan; van Seeters, Tom; Smit, Ewoud J.; Viergever, Max A.; Prokop, Mathias

    2011-07-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  17. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    Energy Technology Data Exchange (ETDEWEB)

    Mendrik, Adrienne M; Van Ginneken, Bram; Viergever, Max A [Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands); Vonken, Evert-jan; De Jong, Hugo W; Riordan, Alan; Van Seeters, Tom; Smit, Ewoud J; Prokop, Mathias, E-mail: a.m.mendrik@gmail.com [Radiology Department, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)

    2011-07-07

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  18. Optical bedside monitoring of cerebral perfusion: technological and methodological advances applied in a study on acute ischemic stroke

    Science.gov (United States)

    Steinkellner, Oliver; Gruber, Clemens; Wabnitz, Heidrun; Jelzow, Alexander; Steinbrink, Jens; Fiebach, Jochen B.; MacDonald, Rainer; Obrig, Hellmuth

    2010-11-01

    We present results of a clinical study on bedside perfusion monitoring of the human brain by optical bolus tracking. We measure the kinetics of the contrast agent indocyanine green using time-domain near-IR spectroscopy (tdNIRS) in 10 patients suffering from acute unilateral ischemic stroke. In all patients, a delay of the bolus over the affected when compared to the unaffected hemisphere is found (mean: 1.5 s, range: 0.2 s to 5.2 s). A portable time-domain near-IR reflectometer is optimized and approved for clinical studies. Data analysis based on statistical moments of time-of-flight distributions of diffusely reflected photons enables high sensitivity to intracerebral changes in bolus kinetics. Since the second centralized moment, variance, is preferentially sensitive to deep absorption changes, it provides a suitable representation of the cerebral signals relevant for perfusion monitoring in stroke. We show that variance-based bolus tracking is also less susceptible to motion artifacts, which often occur in severely affected patients. We present data that clearly manifest the applicability of the tdNIRS approach to assess cerebral perfusion in acute stroke patients at the bedside. This may be of high relevance to its introduction as a monitoring tool on stroke units.

  19. Pressure- and flow-controlled media perfusion differently modify vascular mechanics in lung decellularization.

    Science.gov (United States)

    da Palma, Renata K; Campillo, Noelia; Uriarte, Juan J; Oliveira, Luis V F; Navajas, Daniel; Farré, Ramon

    2015-09-01

    Organ biofabrication is a potential future alternative for obtaining viable organs for transplantation. Achieving intact scaffolds to be recellularized is a key step in lung bioengineering. Perfusion of decellularizing media through the pulmonary artery has shown to be effective. How vascular perfusion pressure and flow vary throughout lung decellularization, which is not well known, is important for optimizing the process (minimizing time) while ensuring scaffold integrity (no barotrauma). This work was aimed at characterizing the pressure/flow relationship at the pulmonary vasculature and at how effective vascular resistance depends on pressure- and flow-controlled variables when applying different methods of media perfusion for lung decellularization. Lungs from 43 healthy mice (C57BL/6; 7-8 weeks old) were investigated. After excision and tracheal cannulation, lungs were inflated at 10 cmH2O airway pressure and subjected to conventional decellularization with a solution of 1% sodium dodecyl sulfate (SDS). Pressure (PPA) and flow (V'PA) at the pulmonary artery were continuously measured. Decellularization media was perfused through the pulmonary artery: (a) at constant PPA=20 cmH2O or (b) at constant V'PA=0.5 and 0.2 ml/min. Effective vascular resistance was computed as Rv=PPA/V'PA. Rv (in cmH2O/(ml/min)); mean±SE) considerably varied throughout lung decellularization, particularly for pressure-controlled perfusion (from 29.1±3.0 in baseline to a maximum of 664.1±164.3 (pperfusion (from 49.9±3.3 and 79.5±5.1 in baseline to a maximum of 114.4±13.9 and 211.7±70.5 (pperfusion mechanics throughout decellularization provides information relevant for optimizing the process time while ensuring that vascular pressure is kept within a safety range to preserve the organ scaffold integrity.

  20. Early whole-brain CT perfusion for detection of patients at risk for delayed cerebral ischemia after subarachnoid hemorrhage.

    Science.gov (United States)

    Malinova, Vesna; Dolatowski, Karoline; Schramm, Peter; Moerer, Onnen; Rohde, Veit; Mielke, Dorothee

    2016-07-01

    OBJECT This prospective study investigated the role of whole-brain CT perfusion (CTP) studies in the identification of patients at risk for delayed ischemic neurological deficits (DIND) and of tissue at risk for delayed cerebral infarction (DCI). METHODS Forty-three patients with aneurysmal subarachnoid hemorrhage (aSAH) were included in this study. A CTP study was routinely performed in the early phase (Day 3). The CTP study was repeated in cases of transcranial Doppler sonography (TCD)-measured blood flow velocity (BFV) increase of > 50 cm/sec within 24 hours and/or on Day 7 in patients who were intubated/sedated. RESULTS Early CTP studies revealed perfusion deficits in 14 patients, of whom 10 patients (72%) developed DIND, and 6 of these 10 patients (60%) had DCI. Three of the 14 patients (21%) with early perfusion deficits developed DCI without having had DIND, and the remaining patient (7%) had neither DIND nor DCI. There was a statistically significant correlation between early perfusion deficits and occurrence of DIND and DCI (p 50 cm/sec within 24 hours, revealing a perfusion deficit in 3 of them (38%). Two of the 3 patients (67%) developed DCI without preceding DIND and 1 patient (33%) had DIND without DCI. In 4 of the 7 patients (57%) who were sedated and/or comatose, additional CTP studies on Day 7 showed perfusion deficits. All 4 patients developed DCI. CONCLUSIONS Whole-brain CTP on Day 3 after aSAH allows early and reliable identification of patients at risk for DIND and tissue at risk for DCI. Additional CTP investigations, guided by TCD-measured BFV increase or persisting coma, do not contribute to information gain.

  1. Transfer function analysis for the assessment of cerebral autoregulation using spontaneous oscillations in blood pressure and cerebral blood flow

    NARCIS (Netherlands)

    Abeelen, A.S.S. van den; Beek, A.H. van; Slump, C.H.; Panerai, R.B.; Claassen, J.A.H.R.

    2014-01-01

    Cerebral autoregulation (CA) is a key mechanism to protect the brain against excessive fluctuations in blood pressure (BP) and maintain cerebral blood flow. Analyzing the relationship between spontaneous BP and cerebral blood flow velocity (CBFV) using transfer function analysis is a widely used tec

  2. Early Cerebral Circulation Disturbance in Patients Suffering from Severe Traumatic Brain Injury (TBI): A Xenon CT and Perfusion CT Study

    Science.gov (United States)

    HONDA, Mitsuru; ICHIBAYASHI, Ryo; YOKOMURO, Hiroki; YOSHIHARA, Katsunori; MASUDA, Hiroyuki; HAGA, Daisuke; SEIKI, Yoshikatsu; KUDOH, Chiaki; KISHI, Taichi

    2016-01-01

    Traumatic brain injury (TBI) is widely known to cause dynamic changes in cerebral blood flow (CBF). Ischemia is a common and deleterious secondary injury following TBI. Detecting early ischemia in TBI patients is important to prevent further advancement and deterioration of the brain tissue. The purpose of this study was to clarify the cerebral circulatory disturbance during the early phase and whether it can be used to predict patient outcome. A total of 90 patients with TBI underwent a xenon-computed tomography (Xe-CT) and subsequently perfusion CT to evaluate the cerebral circulation on days 1–3. We measured CBF using Xe-CT and mean transit time (MTT: the width between two inflection points [maximum upward slope and maximum downward slope from inflow to outflow of the contrast agent]) using perfusion CT and calculated the cerebral blood volume (CBV) using the AZ-7000W98 computer system. The relationships of the hemodynamic parameters CBF, MTT, and CBV to the Glasgow Coma Scale (GCS) score and the Glasgow Outcome Scale (GOS) score were examined. There were no significant differences in CBF, MTT, and CBV among GCS3–4, GCS5–6, and GCS7–8 groups. The patients with a favorable outcome (GR and MD) had significantly higher CBF and lower MTT than those with an unfavorable one (SD, VS, or D). The discriminant analysis of these parameters could predict patient outcome with a probability of 70.6%. During the early phase, CBF reduction and MTT prolongation might influence the clinical outcome of TBI. These parameters are helpful for evaluating the severity of cerebral circulatory disturbance and predicting the outcome of TBI patients. PMID:27356957

  3. Early Cerebral Circulation Disturbance in Patients Suffering from Severe Traumatic Brain Injury (TBI): A Xenon CT and Perfusion CT Study.

    Science.gov (United States)

    Honda, Mitsuru; Ichibayashi, Ryo; Yokomuro, Hiroki; Yoshihara, Katsunori; Masuda, Hiroyuki; Haga, Daisuke; Seiki, Yoshikatsu; Kudoh, Chiaki; Kishi, Taichi

    2016-08-15

    Traumatic brain injury (TBI) is widely known to cause dynamic changes in cerebral blood flow (CBF). Ischemia is a common and deleterious secondary injury following TBI. Detecting early ischemia in TBI patients is important to prevent further advancement and deterioration of the brain tissue. The purpose of this study was to clarify the cerebral circulatory disturbance during the early phase and whether it can be used to predict patient outcome. A total of 90 patients with TBI underwent a xenon-computed tomography (Xe-CT) and subsequently perfusion CT to evaluate the cerebral circulation on days 1-3. We measured CBF using Xe-CT and mean transit time (MTT: the width between two inflection points [maximum upward slope and maximum downward slope from inflow to outflow of the contrast agent]) using perfusion CT and calculated the cerebral blood volume (CBV) using the AZ-7000W98 computer system. The relationships of the hemodynamic parameters CBF, MTT, and CBV to the Glasgow Coma Scale (GCS) score and the Glasgow Outcome Scale (GOS) score were examined. There were no significant differences in CBF, MTT, and CBV among GCS3-4, GCS5-6, and GCS7-8 groups. The patients with a favorable outcome (GR and MD) had significantly higher CBF and lower MTT than those with an unfavorable one (SD, VS, or D). The discriminant analysis of these parameters could predict patient outcome with a probability of 70.6%. During the early phase, CBF reduction and MTT prolongation might influence the clinical outcome of TBI. These parameters are helpful for evaluating the severity of cerebral circulatory disturbance and predicting the outcome of TBI patients.

  4. Cerebral perfusion MR imaging using FAIR-HASTE in chronic carotid occlusive disease: comparison with dynamic susceptibility contrast-perfusion MR imaging.

    Directory of Open Access Journals (Sweden)

    Ida,Kentaro

    2006-08-01

    Full Text Available To determine the efficacy of flow-sensitive alternating inversion recovery using half-Fourier single-shot turbo spin-echo (FAIR-HASTE in detecting cerebral hypoperfusion in chronic carotid occlusive disease, we subjected 12 patients with various degrees of cervical internal carotid artery stenoses and/or occlusion (Stenosis group and 24 volunteers (Normal group to FAIR-HASTE. In addition, 10 out of 12 patients in the Stenosis group underwent dynamic susceptibility contrast-perfusion magnetic resonance imaging (DSC-pMRI before and after revascularization in the dominantly affected side. The absolute asymmetry indexes (AIs of both cerebral hemispheres in the Normal and Stenosis groups were compared in FAIR-HASTE. In addition, the AIs were compared with those in the Stenosis group before and after revascularization in both FAIR-HASTE and regional cerebral blood flow (rCBF, calculated with DSC-pMRI. A statistically significant difference was recognized between the AIs in the Normal and Stenosis groups (AI = 2.25 +- 1.92, 8.09 +- 4.60, respectively ; p < 0.0001. Furthermore, in the Stenosis group the AIs on both FAIR-HASTE (8.88 +- 4.93, 2.22 +- 1.79, respectively ; p = 0.0003 and rCBF (7.13 +- 3.57, 1.25 +- 1.33, respectively ; p = 0.0003 significantly decreased after revascularization. In the Stenosis group, before revascularization, signal intensity on both FAIR-HASTE and rCBF had a tendency to be lower in the dominantly affected side. FAIR-HASTE imaging was useful in the detection and evaluation of cerebral hypoperfusion in chronic occlusive carotid disease.

  5. Comparison of cerebral blood volume and permeability in preoperative grading of intracranial glioma using CT perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Bei; Ling, Hua Wei; Chen, Ke Min [Shanghai Jiaotong University, Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai (China); Jiang, Hong [Shanghai Jiaotong University, Department of Pathology, Ruijin Hospital, School of Medicine, Shanghai (China); Zhu, Yan Bo [Shanghai Jiaotong University, Department of Neurosurgery, Ruijin Hospital, School of Medicine, Shanghai (China)

    2006-10-15

    Regional cerebral blood volume (rCBV) and permeability surfaces (rPS) permit in vivo assessment of glioma microvasculature, which provides quite important pathophysiological information in grading gliomas. The aim of our study was to simultaneously examine rCBV and rPS in glioma patients to determine their correlation with histological grade using CT perfusion imaging. A total of 22 patients with gliomas underwent multislice CT perfusion imaging preoperatively. Low-grade and high-grade groups were categorized corresponding to WHO grade II gliomas and WHO grade III or IV gliomas, respectively, as determined by histopathological examination. rCBVs and rPSs were obtained from regions of maximal abnormality in tumor parenchyma on CBV and PS color perfusion maps. Perfusion parameters were compared using the Kruskal-Wallis test in order to evaluate the differences in relation to tumor grade. The Pearson coefficients of rCBV and rPS for each tumor grade were assessed using SPSS 13.0 software. (orig.)

  6. Rapid identification of a major diffusion/perfusion mismatch in distal internal carotid artery or middle cerebral artery ischemic stroke

    Directory of Open Access Journals (Sweden)

    Hakimelahi Reza

    2012-11-01

    Full Text Available Abstract Background We tested the hypothesis that in patients with occlusion of the terminal internal carotid artery and/or the proximal middle cerebral artery, a diffusion abnormality of 70 ml or less is accompanied by a diffusion/perfusion mismatch of at least 100%. Methods Sixty-eight consecutive patients with terminal ICA and/or proximal MCA occlusions and who underwent diffusion/perfusion MRI within 24 hours of stroke onset were retrospectively identified. DWI and mean transit time (MTT volumes were measured. Prospectively, 48 consecutive patients were identified with the same inclusion criteria. DWI and time to peak (TTP lesion volumes were measured. A large mismatch volume was defined as an MTT or TTP abnormality at least twice the DWI lesion volume. Results In the retrospective study, 49 of 68 patients had a DWI lesion volume ≤ 70 ml (mean 20.2 ml; SEM 2.9 ml. A DWI/MTT mismatch of > 100% was observed in all 49 patients (P  100% was present in all 35 (P  Conclusions Acute stroke patients with major anterior circulation artery occlusion are exceedingly likely to have a major diffusion/perfusion mismatch if the diffusion lesion volume is 70 ml or less. This suggests that physiology-based patient assessments may be made using only vessel imaging and diffusion MRI as a simple alternative to perfusion imaging.

  7. NO mediates downregulation of RBF after a prolonged reduction of renal perfusion pressure in SHR

    DEFF Research Database (Denmark)

    Sørensen, Charlotte Mehlin; Leyssac, Paul Peter; Skott, Ole

    2003-01-01

    The aim of the study was to investigate mechanisms underlying the downregulation of renal blood flow (RBF) after a prolonged reduction in renal perfusion pressure (RPP) in adult spontaneously hypertensive rats (SHR). We tested the effect on the RBF response of clamping plasma ANG II in sevoflurane...

  8. Pressure-driven microfluidic perfusion culture device for integrated dose-response assays.

    Science.gov (United States)

    Hattori, Koji; Sugiura, Shinji; Kanamori, Toshiyuki

    2013-12-01

    Cell-based assays are widely used in the various stages of drug discovery. Advances in microfluidic systems over the past two decades have enabled them to become a powerful tool for cell-based assays to achieve both reliability and high throughput. The interface between the micro-world and macro-world is important in industrial assay processes. Therefore, microfluidic cell-based assays using pressure-driven liquid handling are an ideal platform for integrated assays. The aim of this article is to review recent advancements in microfluidic cell-based assays focusing on a pressure-driven perfusion culture device. Here, we review the development of microfluidic cell-based assay devices and discuss the techniques involved in designing a microfluidic network, device fabrication, liquid and cell manipulation, and detection schemes for pressure-driven perfusion culture devices. Finally, we describe recent progress in semiautomatic and reliable pressure-driven microfluidic cell-based assays.

  9. Color-coded perfused blood volume imaging using multidetector CT: initial results of whole-brain perfusion analysis in acute cerebral ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Kloska, Stephan P.; Fischer, Tobias; Fischbach, Roman; Heindel, Walter [University of Muenster, Department of Clinical Radiology, Muenster (Germany); Nabavi, Darius G.; Dittrich, Ralf; Ringelstein, E.B. [University of Muenster, Department of Neurology, Muenster (Germany); Ditt, Hendrik; Klotz, Ernst [Siemens AG, Medical Solutions, Forchheim (Germany)

    2007-09-15

    Computed tomography (CT) is still the primary imaging modality following acute stroke. To evaluate a prototype of software for the calculation of color-coded whole-brain perfused blood volume (PBV) images from CT angiography (CTA) and nonenhanced CT (NECT) scans, we studied 14 patients with suspected acute ischemia of the anterior cerebral circulation. PBV calculations were performed retrospectively. The detection rate of ischemic changes in the PBV images was compared with NECT. The volume of ischemic changes in PBV was correlated with the infarct volume on follow-up examination taking potential vessel recanalization into account. PBV demonstrated ischemic changes in 12/12 patients with proven infarction and was superior to NECT (8/12) in the detection of early ischemia. Moreover, PBV demonstrated the best correlation coefficient with the follow-up infarct volume (Pearson's R = 0.957; P = 0.003) for patients with proven recanalization of initially occluded cerebral arteries. In summary, PBV appears to be more accurate in the detection of early infarction compared to NECT and mainly visualizes the irreversibly damaged ischemic tissue. (orig.)

  10. Characteristic patterns of cerebral blood perfusion and cognitive impairment in patients with Parkinsons disease

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y. J.; Park, M. J.; Cha, J. G.; Kim, S. H.; Kim, J. W.; Kang, D. Y. [Dong-A University College of medicine, Pusan (Korea, Republic of)

    2005-07-01

    Parkinsons disease (PD) is a neurodegenerative disorder that represents cognitive impairment as well as motor symptoms. Even in the early stages of PD, cognitive alterations can be demonstrated by careful neuropsychological test. The purposes of this study are to investigate the pattern of cognitive impairment and the regional cerebral blood flow (rCBF) using Tc-99m HMPAO SPECT in patients with PD. One hundred and twenty two patients with PD and 35 control subjects participated in this study. Patients with PD who had dementia clinically or K-MMSE score below 25 points or with severe motor dysfunction to interfere with the tests were also excluded. They were all matched for age (61{+-}10 vs 61{+-}8), education periods (8.8{+-}4.9 vs 8.8{+-}4.5), and K-MMSE score (27{+-}1.6 vs 27{+-}1.5). All subjects were evaluated using the Seoul Neuropsychological Screening Battery (SNSB) and Tc-99m HMPAO SPECT with SPM software to measure rCBF. Patients with PD performed worse in digit span backward, Rey Complex Figure Test, visual memory, semantic fluency, stroop test, and alternating hand movement test(p<0.05) compared with control group. On SNSB test, 100 patients (82.0%) showed some abnormalities. Eighty-six patients (70.5%) showed frontal dysfunction, 47 (38.5%) memory impairment, 33 (27.0%) language dysfunction, 25 (20.5%) attention deficit and 22 (18.3%) visuospatial dysfunction in the order of frequency. Eight patients with PD showed single memory domain MCI and 28 single non-memory domain MCI (20 frontal dysfunction). Multiple domain MCI was found in 64 patients with PD. SPM analysis of the SPECT image revealed multiple perfusion deficit in the both frontal, temporal, both limbic lobes, Lt. parietal and Lt. Putamen. It is concluded that abnormalities of cognitive function be detected very commonly in patients with PD. MCI in PD patients is most frequently involved in the item of frontal lobe function. SPECT image might be helpful to explain cognitive impairment in some

  11. CT perfusion assessment of Moyamoya syndrome before and after direct revascularization (superficial temporal artery to middle cerebral artery bypass)

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yueqin [Hospital of Qingdao University, Department of Radiology, Qingdao (China); Hospital of Jining Medical College, CT Department, Jining (China); Xu, Wenjian [Hospital of Qingdao University, Department of Radiology, Qingdao (China); Guo, Xiang; Shi, Zhitao; Sun, Zhanguo; Wang, Jiehuan [Hospital of Jining Medical College, CT Department, Jining (China); Gao, Lingyun [Hospital of Jining Medical College, MR Department, Jining (China); Jin, Feng [Hospital of Jining Medical College, Department of Neurosurgery, Jining (China); Chen, Weijian; Yang, Yunjun [Hospital of Wenzhou Medical University, Department of Radiology, Wenzhou (China)

    2016-01-15

    To evaluate the utility of CT perfusion (CTP) for the assessment of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis in patients with Moyamoya syndrome (MMS). Twenty-four consecutive MMS patients, who underwent unilateral STA-MCA bypass surgery, received CTP before and after surgery. The relative perfusion parameter values of surgical hemispheres before treatment were compared with post-treatment values. All patients underwent CT angiography (CTA) before and after surgery in order to confirm the patency of bypass. The follow-up CTA after surgery clearly demonstrated 20 (20/24, 83.3 %) bypass arteries, whereas four (16.7 %) bypass arteries were occluded or very small. Postoperative rMTT and rTTP values (P < 0.05) of the surgical side were significantly lower than pre-operation. In patients (n = 20) with bypass patency, postoperative rCBF, rMTT and rTTP values (P < 0.05) of the surgical side were significantly improved. However, the differences of all parameters were not significant (P > 0.05) in the patients (n = 4) without bypass patency after revascularization. This study demonstrates that CTP can provide a crucial quantitative assessment of cerebral haemodynamic changes in MMS before and after STA-MCA anastomosis. (orig.)

  12. Three-dimensional mapping of local cerebral perfusion in alcoholic encephalopathy with and without Wernicke-Korsakoff syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Hata, T.; Meyer, J.S.; Tanahashi, N.; Ishikawa, Y.; Imai, A.; Shinohara, T.; Velez, M.; Fann, W.E.; Kandula, P.; Sakai, F.

    1987-02-01

    Seventeen severe chronic alcoholic patients with and without Wernicke-Korsakoff syndrome (WKS) were examined prospectively after being treated by withdrawal from alcohol. The WKS patients also received thiamine supplements. Three-dimensional measurements of local cerebral blood flow (LCBF) and local partition coefficients (L lambda) were made utilizing xenon contrast computed tomography (Xe CT-CBF). Results were displayed as color-coded brain maps before and after treatment and these were correlated with neurological and cognitive examinations. Before treatment chronic alcoholics without WKS (n = 10) showed diffuse reductions of LCBF values throughout all gray matter including hypothalamus, vicinity of nucleus basalis of Meynert, thalamus, and basal ganglia. Similar, but more severe, reductions were seen in patients with WKS (n = 7), however, white matter perfusion was also reduced. In WKS, most prominent reductions of LCBF were also seen in hypothalamus and basal forebrain nuclei but thalamus, basal ganglia, and limbic systems were severely reduced. After treatment, both groups with alcoholic encephalopathy showed marked clinical improvement and cerebral perfusion was restored toward normal. Chronic alcohol abuse, in the absence of thiamine deficiency, reduces CBF by direct neurotoxic effects. If thiamine deficiency is also present, more severe and localized hemodynamic reductions are superimposed.

  13. User friendly analysis of MR investigations of the cerebral perfusion: Windows {sup trademark} -based image processing; Benutzerfreundliche Auswertung von MR-Untersuchungen der zerebralen Perfusion: Windows {sup trademark} -basierte Bildverarbeitung

    Energy Technology Data Exchange (ETDEWEB)

    Wittsack, H.J.; Moedder, U. [Inst. fuer Diagnostische Radiologie, Univ. Duesseldorf (Germany); Ritzl, A. [Inst. fuer Medizin, Forschungszentrum Juelich (Germany)

    2002-06-01

    Purpose: Quick and user-friendly analysis of perfusion and diffusion weighted MRI by means of interactive computer software. Method: A Windows {sup trademark} -based software was developed for analysis of perfusion (PWI) and diffusion (DWI) MR imaging. The computer program was developed in the programming language C++ using optimized algorithms, so that a high computing speed on Win95/98/NT systems is achieved. The established SVD algorithms of Oestergaard et al. for quantitative perfusion analysis were implemented. Results: Perfusion parameter maps of the cerebral blood flow (rCBF), the mean transit time (MTT) and the cerebral blood volume (rCBV) in consideration of the arterial input function (AIF) can be calculated and visualized using color tables. Additionally, the calculation of ''time-to-peak'' maps (TTP) and of maps of the percentage change in signal intensity (PC) is possible. The analysis of n = 10 normal persons shows perfusion values that agree with those found in the literature. Discussion: With the computer program developed here color-coded perfusion parameter maps can be calculated easily. Because of the high computing speed it is possible to get information about tissue perfusion on the basis of the large MR data sets even in acute investigations. (orig.) [German] Ziel: Schnelle und bedienerfreundliche Auswertung von perfusions- und diffusions-gewichteten MRT-Daten mittels interaktiver Auswertesoftware. Methoden: Eine Windows {sup trademark} -basierte Software zur Auswertung von Perfusions- (PWI) und Diffusions-MRT (DWI) wurde entwickelt. Das Computerprogramm wurde in der Programmiersprache C++ unter Verwendung optimierter Algorithmen entwickelt, so dass eine hohe Rechengeschwindigkeit auf Win95/98/NT-Systemen erreicht wird. Die etablierten SVD-Algorithmen von Oestergaard zur quantitativen Perfusions-Auswertung wurden implementiert. Ergebnisse: Perfusions-Parameterbilder des zerebralen Blutflusses (rCBF), der mittleren

  14. ORIGINAL ARTICLES Effect of Acupuncture Signal after Brachial Plexus Blockade on Cerebral Blood Perfusion and Brain Cell Function

    Institute of Scientific and Technical Information of China (English)

    RENYong-gong; JIAShao-wei

    2003-01-01

    Objective:Using single photon emission computed tomography (SPECT)to observe the influence of the up-transmitting of acupuncture signal into the brain in health volunteers whose nerve trunk was blocked by anesthetics.Methods:Thirty-one healthy volunteers were divided into two groups,the control group of 20 cases,and the brachial plexus blockade(BPB)group of 11cases,with supraclavicular BPB route adopted.With the control group 2 acupoints were randomly selected(Hegu and Quchi of both sides),while with the BPB group Hegu and Quchi of anesthetic arm side were selected.Siemens ECAM/ICON SPECT system was used to conduct brain imaging using double imaging assay before acupuncture and 99m Tc-ECD imaging agent during acupuncture for cerebral perfusion.The data were quantitatively ana-lyzed by blood functional changing rate (BFCR%) mathematics model.Results:Before acupuncture,the control and BPB groups showed insignificant change by SPECT, but after electro-acupuncture(EA),the control group displayed improved motor and sensory cortex excitability in basal nuclei,contra-lateral thal-amus,parietal and frontal lobe; while BPB group was characterized with reduction of the blood perfusion and cell function of contra-lateral thalamus of anesthetized arm.The difference between the two groups was significant(P<0.01).Conclusion:(1)After BPB,the up-transmitting of the acupuncture signal viaupper limb into the brain,and its strength was impaired or blocked; (2)After BPB, the effect of acupunc-ture on cerebral perfusion and brain cell function of contra-lateral thalamus was impaired or blocked.

  15. The scintigraphic appearance of childhood moyamoya disease on cerebral perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.H. [Department of Radiology, Childrens Hospital Los Angeles, Los Angeles, CA (United States)]|[University of Southern California School of Medicine, Los Angeles (United States); Khonsary, A. [Department of Radiology, Childrens Hospital Los Angeles, Los Angeles, CA (United States)]|[University of Southern California School of Medicine, Los Angeles (United States); Raffel, C. [Department of Surgery, Childrens Hospital Los Angeles (United States)]|[University of Southern California School of Medicine, Los Angeles (United States)

    1996-12-01

    Objective. This study was performed to evaluate the role of single photon emission computed tomography (SPECT) perfusion imaging in the evaluation of patients with moyamoya disease. Materials and methods. Five patients (four female, one male) were studied utilizing iodine-123 iodoamphetamine or technetium-99m hexamethylpropyleneamine oxime SPECT. The data were reconstructed into axial, coronal and sagittal sections for review, and compared with CT, MR and/or angiographic images. Results. All five patients had significant perfusion defects. These areas of vascular compromise were seen to cross normal vascular territories, and were greater in number and extent than seen on anatomic sectional imaging. Conclusion. Patients with moyamoya disease have a recognizable pattern of scintigraphic perfusion deficits which should be identified by pediatric imaging physicians. SPECT perfusion studies should be performed in conjunction with other imaging modalities (CT, MR or angiography). (orig.). With 3 figs.

  16. Tratamento cirúrgico das lesões da aorta torácica utilizando parada circulatória total hipotérmica com perfusão cerebral retrógrada Surgical treatment of the pathologies involving thoracic aorta using deep hypothermic total circulatory arrest with retrograde cerebral perfusion

    Directory of Open Access Journals (Sweden)

    Domingo M Braile

    1992-06-01

    ectasia associated with type B dissection. A cava-cava-femoral cardiopulmonary bypass was established with deep hypothermia and total circulatory arrest. Retrograde blood cardioplegia was used for myocardial preservation. During total circulatory arrest retrograde cerebral perfusion was made using arterial line cannulated to the superior vena cava with a flow of 250 to 300 ml/min the central venous pressure monitored at the arm ranged between 30 and 40 cmH2O. Surgical repair was achieved using bovine pericardial tube and patch associated to the biological glue. Duration of cardiopulmonary bypass ranged from 75 to 169 min, total circulatory arrest from 32 to 79 min and retrograde cerebral perfusion from 32 to 79 min. There was no mortality associated to surgery or to immediate postoperative period. There was only one late death, due to septcemia. All other patients are on follow-up. The results show that total circulatory arrest with retrograde cerebral perfusion protects the brain more effectively than conventional total circulatory arrest during surgical treatment of thoracic aorta pathologies that require total circulatory arrest.

  17. INFLUENCE OF LOCAL INFILITRATION ANESTHESIA OF SCALP-POINT ON ACUPUNCTURE INDUCED CHANGES OF CEREBRAL BLOOD PERFUSION DETECTED BY SPECT

    Institute of Scientific and Technical Information of China (English)

    郭长春; 王凡; 贾少微

    2003-01-01

    Objective: To observe the influence of local infiltration anesthesia at the scalp-point on acupuncture stimulation induced changes of cerebral blood perfusion in the brain. Methods: Experiments were conducted in 10 healthy volunteer subjects (8 males and 2 females) who were ordered to take a lying position on a specific bed with their heads keeping in a fixed position. Scalp-point used was Motor Area (MS 6). The first syringe needle (gauge-5) was inserted into the scalp from the upper 1/5 of MS-6 and the second syringe needle inserted into the scalp from the middle 2/5 of MS-6 and advanced downward, with the two needles connected to a HAN's Therapeutic Apparatus. Images of the brain were then taken before and after electroacupuncture (EA) stimulation, and after local injection of 1% lidocaine [mixed with epinephrine (1∶200,000, 3 mL)] plus EA by using Siemens ECAM/ICON Single Photo Emission Computed Tomography (SPECT). Intravenous injection of Ethyl cysteinate dimmer 555 MBq was performed before displaying cerebral images. Data of blood functional changing rat (BFCR%) were analyzed quantitatively using a mathematic model. Results: Before EA stimulation, the blood perfusion and function of cerebral cortex, thalamus, basal ganglion and cerebellum on both sides of the brain were basically symmetry. Following EA of MS-6, BFCR% of the contralateral thalamus, parietal lobe and the frontal lobe increased significantly. Following local infiltration anesthesia, BFCR% of the contralatral thalamus declined markedly (P<0.05). The results of quantitative analysis were in agreement with those of visual observation. Conclusion: Local infiltration anesthesia of the scalp-point can significantly weaken or block EA stimulation induced changes of BFCR%.

  18. Glycopyrrolate does not influence the visual or motor-induced increase in regional cerebral perfusion

    DEFF Research Database (Denmark)

    Rokamp, Kim Z; Olesen, Niels D; Larsson, Henrik B W;

    2014-01-01

    Acetylcholine may contribute to the increase in regional cerebral blood flow (rCBF) during cerebral activation since glycopyrrolate, a potent inhibitor of acetylcholine, abolishes the exercise-induced increase in middle cerebral artery mean flow velocity. We tested the hypothesis that cholinergic...... vasodilatation is important for the increase in rCBF during cerebral activation. The subjects were 11 young healthy males at an age of 24 ± 3 years (mean ± SD). We used arterial spin labeling and blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) to evaluate rCBF with and without...

  19. SPECT measurement of cerebral hemodynamics in transient ischemic attack patients; Evaluation of pathogenesis and detection of misery perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Toyama, Hiroshi; Takeshita, Gen; Takeuchi, Akira; Ejiri, Kazutaka; Maeda, Hisato; Katada, Kazuhiro; Koga, Sukehiko; Ishiyama, Norio; Kanno, Tetsuo (Fujita-Gakuen Health Univ., Toyoake, Aichi (Japan))

    1989-12-01

    To evaluate the cerebral hemodynamics and the pathogenesis by regional cerebral blood flow (rCBF) and regional cerebral blood volume (rCBV), 42 transient ischemic attack (TIA) patients and 9 normal volunteers were studied using SPECT. We classified these patients into Group A (n=23: no occlusion or stenosis of the internal carotid or middle cerebral artery; non large vessel disease) and Group B (n=19: chronic occlusion or severe stenosis of the internal carotid or middle cerebral artery; large vessel disease). We obtained rCBF with {sup 133}Xe inhalation and rCBV with {sup 99m}Tc-red blood cells. Of 9 normal volunteers aged 43-70 yr (mean age 59.8{plus minus} 8.3 yr), the mean rCBF was 45.8{plus minus} 5.1 (ml/100 g brain/min), the mean rCBV was 4.0{plus minus} 0.4 (ml/100 g brain). The examination was done by comparing the values of the affected hemispheres of Group A and Group B patients with the mean rCBF and the mean rCBV of normal volunteers. Eleven out of Group A patients and 15 out of Group B patients showed decreased rCBF. But of those patients, no patients of Group A showed increased rCBV and 6 out of 19 Group B patients showed increased rCBV. Thromboembolic mechanism which is of Group A patients and Group B patients without increased rCBV, and hemodynamic mechanism which is of Group B patients with increased rCBV were considered as the main cause of TIA. Decreased rCBF and increased rCBV in Group B patients can be assumed as the misery perfusion as reported in PET studies. We conclude that SPECT measurement of not only rCBF but also rCBV on TIA patients is very significant to evaluate the pathogenesis and to detect the misery perfusion. (author).

  20. 大脑中动脉狭窄程度与脑灌注的相关性研究%Correlation between stenosis of middle cerebral artery and cerebral perfusion

    Institute of Scientific and Technical Information of China (English)

    史文倩; 石进; 杨帆; 时惠平

    2015-01-01

    Objective To investigate the correlation between stenosis of middle cerebral artery (MCA) and cerebral perfusion in patients with unilateral MCA stenosis.Methods Computed tomography perfusion (CTP) was performed in 34 patients with unilateral MCA stenosis,admitted to our hospital trom April 2012 to March 2013.The CTP parameters of mean transit time,cerebral blood flow,cerebral blood volume and time to peak were measured in regions supplied by anterior cerebral artery,MCA and posterior cerebral artery.All patients were divided into severe stenosis group and moderate stenosis group; the correlation between MCA stenosis and cerebral perfusion was analyzed.Results A decreased perfusion was detected in 25 patients (73.5%),and it was more likely found in the severe stenosis group (18/20,90%) than that in the moderate stenosis group (7/14,50%,P=0.017).The degree ofMCA stenosis was positively correlated with the changes of cerebral perfusion (r=0.381,P=0.026).The ratio of patients with transient ischemic attack (TIA) between the normal cerebral perfusion group and decreased cerebral perfusion group had statistical difference (11.11% vs.72.00%,P=0.004).Conclusion Cerebral perfusion is significantly correlated with the severity of MCA stenosis in unilateral MCA stenosis patients; the proportion of TIA in the low cerebral perfusion patients is higher than that in the normal cerebral perfusion ones.%目的 探讨单侧大脑中动脉(MCA)狭窄患者MCA狭窄程度与脑灌注的相关性.方法 对自2012年4月至2013年3月在北京空军总医院神经内科住院的34例单侧MCA狭窄患者行CT灌注成像(CTP)检查:在双侧半球大脑前动脉、MCA及大脑后动脉供血区选择对称的感兴趣区,测量CTP参数如脑血流量(CBF)、脑血容量(CBV)、平均通过时间(MTT)及达峰时间(TTP)等.并将患者按MCA狭窄程度分组(重度、中度),对狭窄程度与MCA供血区的脑灌注进行等级相关性分析. 结果 34例患者中有25

  1. An improvement of cerebral hemodynamics in a newly developed perfusion area evaluated by intra-arterial SPECT following vascular reconstructive surgery

    Energy Technology Data Exchange (ETDEWEB)

    Nochide, Ichiro [Ehime Univ., Shigenobu (Japan). School of Medicine

    1999-06-01

    The purpose of this study was to evaluate the changes in regional cerebral blood flow (rCBF) and vascular reserve ({Delta}CBF) responding to acetazolamide loading by {sup 133}Xe SPECT. In combination, this study assessed the newly developed region of cerebral perfusion via bypass arteries after surgical vascular reconstruction in 11 hemispheres of 11 patients with atherosclerotic arterial occlusive disease and adult onset moyamoya disease. In patients with atherosclerotic occlusive disease, the cerebral perfusion from bypass arteries mainly developed in the preoperatively low {Delta}CBF territory. Although rCBF did not significantly alter after vascular reconstruction, preoperatively low {Delta}CBF was significantly improved to the normal range in the promotion of postoperatively newly born perfusion from bypass arteries. In 21 hemispheres of 13 patients with adult onset moyamoya disease, the postoperatively newly born perfusion from bypass arteries was significantly developed in the regions with either preoperative low rCBF or low {Delta}CBF. Although both rCBF and {Delta}CBF were significantly improved after the operation, {Delta}CBF was not restored satisfactorily up to the normal range in contrast to the sufficient increase of rCBF, even where the perfusion from the bypass artery was observed after the reconstructive surgeries. Vascular reconstructive surgeries were beneficial for the improvement of {Delta}CBF in the atherosclerotic arterial occlusive disease and rCBF in the adult-onset moyamoya disease, respectively. (author)

  2. Study of cerebral blood flow by magnetic resonance 0. 5 T. Estudio de la perfusion cerebral con RM de 0,5 T

    Energy Technology Data Exchange (ETDEWEB)

    Torrijo, C.; Marti-Bonmati, L.; Palop, C.; Caballero, E.; Poyatos, C.; Sopena, R. (Hospital Doctor Peset. Servicio de Diagnostico por la Imagen. Valencia (Spain))

    1993-01-01

    To asses the cerebral blood flow by magnetic resonance, 1.5 T superconductor imagers have been used, taking slices of the brain for dynamic study following rapid iv administration of gadolinium (Gd-DTPA). Our aim was to attempt to reproduce these data with a 0.5 T superconductor imager. Thirty-two dynamic studies of the head were carried out. The first 10 were used to modify the methodology until a standard technique was achieved, which was employed for the remaining 22:T2*-weighted gradient-echo sequence (TR=50msec, TE=23 msec, angle=10*, thickness=10mm, matrix=128x64, FOV=250 mm), taking 15 slices in 75 seconds following a 20 ml iv bolus of Gd-DTPA. When the signal intensity was measured at the level of the cerebral cortex, a reduction was detected in association with the passage of Gd-DTPA through the cerebral microcirculation, with a mean signal loss of 5.96%[+-]2.25. This signal loss is significant (p<0.01) when compared with that reported in studies in which no contrast agent was used (2.54%[+-]0.6). The maximum signal loss appeared at times varying between 10 and 40 seconds after administration of the contrast medium. It is concluded that passage (perfusion) through the cerebral microcirculation can be observed at 0.5 T, although the attenuation values obtained are lower than those reported by other authors in their series. The time at which the signal loss appears after iv contrast administration is unpredictable, fact which further limits the utility of this methodology. (Author)

  3. Cerebral perfusion and cerebrovascular reactivity are reduced in white matter hyperintensities

    DEFF Research Database (Denmark)

    Marstrand, J.R.; Garde, E; Rostrup, Egill;

    2002-01-01

    reported global reductions in cerebral blood flow (CBF) and cerebral vascular reactivity. In this study, we examined localized hemodynamic status to compare WMH to normal appearing white matter (NAWM). METHODS: A group of 21 normal 85-year-old subjects were studied using dynamic contrast-enhanced MRI...... together with administration of acetazolamide. From a combination of anatomic images with different signal weighting, regions of interest were generated corresponding to gray and white matter and WMH. Localized measurements of CBF and cerebral blood volume (CBV) and mean transit time were obtained directly...

  4. Accuracy of computed tomography perfusion in detecting delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage: A meta-analysis

    Directory of Open Access Journals (Sweden)

    Haogeng Sun

    2013-01-01

    Full Text Available Background and Purpose: In recent years, significant literature shows that computed tomography perfusion (CTP can provide sufficient information on cerebral hemodynamics and effectively indicate delayed cerebral ischemia (DCI before the development of infarction. We aimed at performing a meta-analysis to provide a more full and accurate evaluation of CTP and CTP parameters in detecting DCI in patients with aneurysmal subarachnoid hemorrhage. Materials and Methods: We searched the PubMed, MedLine, Embase and Cochrane databases for analysis published from February 2005 to February 2013. We extracted CTP parameters, including cerebral blood volume (CBV, cerebral blood flow (CBF, mean transit time (MTT, time to peak (TTP, interhemispheric ratios for CBV and CBF and interhemispheric differences for MTT and TTP. Pooled estimates of sensitivity, specificity, positive likelihood ratio (PLR, negative likelihood ratio (NLR, diagnostic odds ratio (DOR and the summary receiver-operating characteristic curve were determined. Results: Four research studies are met the inclusion criteria for the analysis. The pooled sensitivity, specificity, PLR, NLR and DOR of CTP for detecting the DCI were 82%, 82%, 4.56, 0.22 and 20.96, respectively. Through the evaluation of absolute CTP parameters, CBF and MTT showed diagnostic value for DCI, but CBF and TTP did not. Moreover, CBF ratio, MTT difference and TTP difference showed more diagnostic value than CBV ratio in DCI detection by the assessment of relative CTP parameters. Conclusions: As a non-invasive and short time consuming screening method, CTP own a high diagnostic value for the detection of DCI after aneurysm rupture.

  5. Microvascular hemodynamics in human hypothermic circulatory arrest and selective antegrade cerebral perfusion

    NARCIS (Netherlands)

    P.W.G. Elbers; A. Ozdemir; R.H. Heijmen; J. Heeren; M. van Iterson; E.P.A. van Dongen; C. Ince

    2010-01-01

    Objective: The behavior of the human microcirculation in the setting of cardiac arrest is largely unknown. Animal experiments have consistently revealed that global hemodynamics do not necessarily reflect microvascular perfusion. In addition, the time it takes for capillary blood flow to stop after

  6. Cerebral Metabolic Profiling of Hypothermic Circulatory Arrest with and Without Antegrade Selective Cerebral Perfusion: Evidence from Nontargeted Tissue Metabolomics in a Rabbit Model

    Institute of Scientific and Technical Information of China (English)

    Li-Hua Zou; Jin-Ping Liu; Hao Zhang; Shu-Bin Wu; Bing-Yang Ji

    2016-01-01

    Background:Antegrade selective cerebral perfusion (ASCP) is regarded to perform cerebral protection during the thoracic aorta surgery as an adjunctive technique to deep hypothermic circulatory arrest (DHCA).However,brain metabolism profile after ASCP has not been systematically investigated by metabolomics technology.Methods:To clarify the metabolomics profiling of ASCP,12 New Zealand white rabbits were randomly assigned into 60 min DHCA with (DHCA+ASCP [DA] group,n =6) and without (DHCA [D] group,n =6) ASCP according to the random number table.ASCP was conducted by cannulation on the right subclavian artery and cross-clamping of the innominate artery.Rabbits were sacrificed 60 min after weaning off cardiopulmonary bypass.The metabolic features of the cerebral cortex were analyzed by a nontargeted metabolic profiling strategy based on gas chromatography-mass spectrometry.Variable importance projection values exceeding 1.0 were selected as potentially changed metabolites,and then Student's t-test was applied to test for statistical significance between the two groups.Results:Metabolic profiling of brain was distinctive significantly between the two groups (Q2y =0.88 for partial least squares-DA model).In comparing to group D,62 definable metabolites were varied significantly after ASCP,which were mainly related to amino acid metabolism,carbohydrate metabolism,and lipid metabolism.Kyoto Encyclopedia of Genes and Genomes analysis revealed that metabolic pathways after DHCA with ASCP were mainly involved in the activated glycolytic pathway,subdued anaerobic metabolism,and oxidative stress.In addition,L-kynurenine (P =0.0019),5-methoxyindole-3-acetic acid (P =0.0499),and 5-hydroxyindole-3-acetic acid (P =0.0495) in tryptophan metabolism pathways were decreased,and citrulline (P =0.0158) in urea cycle was increased in group DA comparing to group D.Conclusions:The present study applied metabolomics analysis to identify the cerebral metabolic profiling in rabbits with ASCP

  7. Arterial pressure variations as parameters of brain perfusion in response to central blood volume depletion and repletion

    Directory of Open Access Journals (Sweden)

    Anne-Sophie G.T. Bronzwaer

    2014-04-01

    Full Text Available Rationale:A critical reduction in central blood volume (CBV is often characterized by hemodynamic instability. Restoration of a volume deficit may be established by goal-directed fluid therapy guided by respiration-related variation in systolic- and pulse pressure (SPV and PPV. Stroke volume index (SVI serves as a surrogate end-point of a fluid challenge but tissue perfusion itself has not been addressed. Objective: To delineate the relationship between arterial pressure variations, SVI and regional brain perfusion during CBV depletion and repletion in spontaneously breathing volunteers. Methods: This study quantified in 14 healthy subjects (11 male the effects of CBV depletion (by 30 and 70 degrees passive head-up tilt (HUT and a fluid challenge (by tilt back on CBV (thoracic admittance, mean middle cerebral artery (MCA blood flow velocity (Vmean, SVI, cardiac index (CI , PPV and SPV. Results: PPV (103±89%, p< 0.05 and SPV (136±117%, p< 0.05 increased with progression of central hypovolemia manifested by a reduction in thoracic admittance (11±5%, p< 0.001, SVI (28±6%, p< 0.001, CI (6±8%, p< 0.001 and MCAVmean (17±7%, p< 0.05 but not in arterial pressure. The reduction in MCAVmean correlated to the fall in SVI (R2=0.52, p< 0.0001 and inversely to PPV and SPV (R2=0.46 (p< 0.0001 and R2=0.45 (p< 0.0001, respectively. PPV and SPV predicted a ≥15% reduction in MCAVmean and SVI with comparable sensitivity (67%/ 67% vs. 63%/ 68% respectively and specificity (89%/94% vs. 89%/94%, respectively. A rapid fluid challenge by tilt-back restored all parameters to baseline values within one minute. Conclusion: In spontaneously breathing subjects, a reduction in MCAVmean was related to an increase in PPV and SPV during graded CBV depletion and repletion. Specifically, PPV and SPV predicted changes in both SVI and MCAVmean with comparable sensitivity and specificity, however the predictive value is limited in spontaneously breathing subjects.

  8. Early Effects of Combretastatin-A4 Disodium Phosphate on Tumor Perfusion and Interstitial Fluid Pressure

    Directory of Open Access Journals (Sweden)

    Carsten D. Ley

    2007-02-01

    Full Text Available Combretastatin-A4 disodium phosphate (CA4DP is a vascular-disruptive agent that causes an abrupt decrease in tumor blood flow. The direct actions of CA4DP include increases in vascular permeability and destabilization of the endothelial cytoskeleton, which are thought to contribute to occlusion of the tumor vasculature. It has been proposed that increased permeability causes a transient increase in interstitial fluid pressure (IFP, which in turn could collapse intratumoral blood vessels. We examined the immediate effects of CA4DP on tumor IFP in C3H mammary carcinoma. Mice were treated with 100 mg/kg CA4DP by intraperitoneal injection. Tumor perfusion was recorded by laser Doppler flowmetry at separate time points, and IFP was recorded continuously by the wickin-needle method. In this study, we found that CA4DP treatment resulted in a rapid reduction in tumor perfusion, followed by a decrease in IFP; no increases in IFP were observed. This suggests that CA4DP-induced reductions in tumor perfusion are not dependent on increases in IFP.

  9. Iterative image reconstruction for cerebral perfusion CT using a pre-contrast scan induced edge-preserving prior

    Science.gov (United States)

    Ma, Jianhua; Zhang, Hua; Gao, Yang; Huang, Jing; Liang, Zhengrong; Feng, Qianjing; Chen, Wufan

    2012-11-01

    Cerebral perfusion x-ray computed tomography (PCT) imaging, which detects and characterizes the ischemic penumbra, and assesses blood-brain barrier permeability with acute stroke or chronic cerebrovascular diseases, has been developed extensively over the past decades. However, due to its sequential scan protocol, the associated radiation dose has raised significant concerns to patients. Therefore, in this study we developed an iterative image reconstruction algorithm based on the maximum a posterior (MAP) principle to yield a clinically acceptable cerebral PCT image with lower milliampere-seconds (mA s). To preserve the edges of the reconstructed image, an edge-preserving prior was designed using a normal-dose pre-contrast unenhanced scan. For simplicity, the present algorithm was termed as ‘MAP-ndiNLM’. Evaluations with the digital phantom and the simulated low-dose clinical brain PCT datasets clearly demonstrate that the MAP-ndiNLM method can achieve more significant gains than the existing FBP and MAP-Huber algorithms with better image noise reduction, low-contrast object detection and resolution preservation. More importantly, the MAP-ndiNLM method can yield more accurate kinetic enhanced details and diagnostic hemodynamic parameter maps than the MAP-Huber method.

  10. The Application of Diffusion- and Perfusion-Weighted Magnetic Resonance Imaging in the Diagnosis and Therapy of Acute Cerebral Infarction

    Directory of Open Access Journals (Sweden)

    Ying Han

    2006-01-01

    Full Text Available Diffusion- and perfusion-weighted magnetic resonance imaging (DWI and PWI was applied for stroke diagnose in 120 acute (<48 h ischemic stroke patients. At hyperacute (<6 h stage, it is difficult to find out the infarction zone in conventional T1 or T2 image, but it is easy in DWI, apparent diffusion coefficient (ADC map; when at 3–6-hour stage it is also easy in PWI, cerebral blood flow (CBF map, cerebral blood volume (CBV map, and mean transit time (MTT map; at acute (6–48 h stage, DWI or PWI is more sensitive than conventional T1 or T2 image too. Combining DWI with ADC, acute and chronic infarction can be distinguished. Besides, penumbra which should be developed in meaning was used as an indication or to evaluate the therapeutic efficacy. There were two cases (<1.5 h that broke the model of penumbra because abnormity was found in DWI but not that in PWI, finally they recovered without any sequela.

  11. Cerebral perfusion and cerebrovascular reactivity are reduced in white matter hyperintensities

    DEFF Research Database (Denmark)

    Marstrand, J.R.; Garde, E; Rostrup, Egill;

    2002-01-01

    BACKGROUND AND PURPOSE: There is growing evidence that white matter hyperintensities (WMH) should not be considered as benign age-dependent changes on MR images but indicate pathological changes with clinical consequences. Previous studies comparing subjects with WMH to normal controls have...... reported global reductions in cerebral blood flow (CBF) and cerebral vascular reactivity. In this study, we examined localized hemodynamic status to compare WMH to normal appearing white matter (NAWM). METHODS: A group of 21 normal 85-year-old subjects were studied using dynamic contrast-enhanced MRI...... together with administration of acetazolamide. From a combination of anatomic images with different signal weighting, regions of interest were generated corresponding to gray and white matter and WMH. Localized measurements of CBF and cerebral blood volume (CBV) and mean transit time were obtained directly...

  12. Reduction in cerebral perfusion after heroin administration: a resting state arterial spin labeling study.

    Directory of Open Access Journals (Sweden)

    Niklaus Denier

    Full Text Available Heroin dependence is a chronic relapsing brain disorder, characterized by the compulsion to seek and use heroin. Heroin itself has a strong potential to produce subjective experiences characterized by intense euphoria, relaxation and release from craving. The neurofunctional foundations of these perceived effects are not well known. In this study, we have used pharmacological magnetic resonance imaging (phMRI in 15 heroin-dependent patients from a stable heroin-assisted treatment program to observe the steady state effects of heroin (60 min after administration. Patients were scanned in a cross-over and placebo controlled design. They received an injection of their regular dose of heroin or saline (placebo before or after the scan. As phMRI method, we used a pulsed arterial spin labeling (ASL sequence based on a flow-sensitive alternating inversion recovery (FAIR spin labeling scheme combined with a single-shot 3D GRASE (gradient-spin echo readout on a 3 Tesla scanner. Analysis was performed with Statistical Parametric Mapping (SPM 8, using a general linear model for whole brain comparison between the heroin and placebo conditions. We found that compared to placebo, heroin was associated with reduced perfusion in the left anterior cingulate cortex (ACC, the left medial prefrontal cortex (mPFC and in the insula (both hemispheres. Analysis of extracted perfusion values indicate strong effect sizes and no gender related differences. Reduced perfusion in these brain areas may indicate self- and emotional regulation effects of heroin in maintenance treatment.

  13. Optical coherence tomography microangiography for monitoring the response of vascular perfusion to external pressure on human skin tissue

    Science.gov (United States)

    Choi, Woo June; Wang, Hequn; Wang, Ruikang K.

    2014-05-01

    Characterization of the relationship between external pressure and blood flow is important in the examination of pressure-induced disturbance in tissue microcirculation. Optical coherence tomography (OCT)-based microangiography is a promising imaging technique, capable of providing the noninvasive extraction of functional vessels within the skin tissue with capillary-scale resolution. Here, we present a feasibility study of OCT microangiography (OMAG) to evaluate changes in blood perfusion in response to externally applied pressure on human skin tissue in vivo. External force is loaded normal to the tissue surface at the nailfold region of a healthy human volunteer. An incremental force is applied step by step and then followed by an immediate release. Skin perfusion events including baseline are continuously imaged by OMAG, allowing for visualization and quantification of the capillary perfusion in the nailfold tissue. The tissue strain maps are simultaneously evaluated through the available OCT structural images to assess the relationship of the microcirculation response to the applied pressure. The results indicate that the perfusion progressively decreases with the constant increase of pressure. Reactive hyperemia occurs right after the removal of the pressure. The perfusion returns to the baseline level after a few minutes. These findings suggest that OMAG may have great potential for quantitatively assessing tissue microcirculation in the locally pressed tissue in vivo.

  14. Blood-brain barrier permeability is positively correlated with cerebral microvascular perfusion in the early fluid percussion-injured brain of the rat.

    Science.gov (United States)

    Lin, Yong; Pan, Yaohua; Wang, Mingliang; Huang, Xianjian; Yin, Yuhua; Wang, Yu; Jia, Feng; Xiong, Wenhao; Zhang, Nu; Jiang, Ji-yao

    2012-11-01

    The blood-brain barrier (BBB) opening following traumatic brain injury (TBI) provides a chance for therapeutic agents to cross the barrier, yet the reduction of the cerebral microvascular perfusion after TBI may limit the intervention. Meanwhile, optimizing the cerebral capillary perfusion by the strategies such as fluid administration may cause brain edema due to the BBB opening post trauma. To guide the TBI therapy, we characterized the relationship between the changes in the cerebral capillary perfusion and BBB permeability after TBI. First, we observed the changes of the cerebral capillary perfusion by the intracardiac perfusion of Evans Blue and the BBB disruption with magnetic resonance imaging (MRI) in the rat subjected to lateral fluid percussion (FP) brain injury. The correlation between two variables was next evaluated with the correlation analysis. Since related to BBB breakdown, matrix metalloproteinase-9 (MMP-9) activity was finally detected by gelatin zymography. We found that the ratios of the perfused microvessel numbers in the lesioned cortices were significantly reduced at 0 and 1 h post trauma compared with that in the normal cortex, which then dramatically recovered at 4 and 24 h after injury, and that the BBB permeability was greatly augmented in the ipsilateral parts at 4, 12, and 24 h, and in the contralateral area at 24 h after injury compared with that in the uninjured brain. The correlation analysis showed that the BBB permeability increase was related to the restoration of the cerebral capillary perfusion over a 24-h period post trauma. Moreover, the gelatin zymography analysis indicated that the MMP-9 activity in the injured brain increased at 4 h and significantly elevated at 12 and 24 h as compared to that at 0 or 1 h after TBI. Our findings demonstrate that the 4 h post trauma is a critical turning point during the development of TBI, and, importantly, the correlation analysis may guide us how to treat TBI.

  15. Increased pressure-induced tone in rat parenchymal arterioles vs. middle cerebral arteries: role of ion channels and calcium sensitivity.

    Science.gov (United States)

    Cipolla, Marilyn J; Sweet, Julie; Chan, Siu-Lung; Tavares, Matthew J; Gokina, Natalia; Brayden, Joseph E

    2014-07-01

    Brain parenchymal arterioles (PAs) are high-resistance vessels that branch off pial arteries and perfuse the brain parenchyma. PAs are the target of cerebral small vessel disease and have been shown to have greater pressure-induced tone at lower pressures than pial arteries. We investigated mechanisms by which brain PAs have increased myogenic tone compared with middle cerebral arteries (MCAs), focusing on differences in vascular smooth muscle (VSM) calcium and ion channel function. The amount of myogenic tone and VSM calcium was measured using Fura 2 in isolated and pressurized PAs and MCAs. Increases in intraluminal pressure caused larger increases in tone and cytosolic calcium in PAs compared with MCAs. At 50 mmHg, myogenic tone was 37 ± 5% for PAs vs. 6.5 ± 4% for MCAs (P channel (VDCC) inhibitor nifedipine than MCAs (EC50 for PAs was 3.5 ± 0.4 vs. 82.1 ± 2.1 nmol/l for MCAs;P channel inhibitor iberiotoxin, whereas MCAs constricted ∼15%. Thus increased myogenic tone in PAs appears related to differences in ion channel activity that promotes VSM membrane depolarization but not to a direct sensitization of the contractile apparatus to calcium.

  16. Nova técnica: operação de Norwood com perfusão regional cerebral e coronariana New technique: Norwood operation with regional cerebral and coronary perfusion

    Directory of Open Access Journals (Sweden)

    Gláucio Furlanetto

    2009-12-01

    Full Text Available OBJETIVO: Avaliar o resultado imediato da operação de Norwood modificado com nova técnica de perfusão regional cerebral (PRCeA anterógrada associado a perfusão regional coronariana (PRCoR retrógrada em substituição à parada circulatória total com hipotermia profunda em crianças portadoras da Síndrome da Hipoplasia do Coração Esquerdo (SHCE com aorta ascendente extremamente hipoplásica (AH. MÉTODOS: No período de dezembro de 2006 a fevereiro de 2008, a operação de Norwood modificado com tubo entre o ventrículo direito e as artérias pulmonares ou shunt tipo Sano foi realizada em oito crianças portadoras de SHCE e aorta ascendente com diâmetro inferior a 3 mm, (quatro do sexo masculino e quatro do sexo feminino com idade média de 9,2 dias (variando de 1 a 29 dias e peso médio de 3,3 kg (variando de 2,7 a 3,8 kg. Utilizada CEC e hipotermia a 25ºC com duas cânulas venosas e anastomose de um enxerto de politetrafluoretileno com a artéria inominada utilizado como linha arterial e para PRCeA. A PRCoR foi realizada por meio de um desvio na linha arterial e colocação de um cateter na aorta ascendente. Foram analisados o resultado cirúrgico imediato e a presença de alterações neurológicas nesse período. RESULTADOS: O resultado cirúrgico imediato revelou mortalidade de 25% e ausência de comprometimento neurológico ao exame clínico. CONCLUSÃO: A operação de Norwood modificado pode ser realizada com PRCeA e PRCoR em crianças com SHCE e AH com resultado cirúrgico imediato satisfatório e ausência de complicações neurológicas.OBJECTIVE: To assess the immediate result of the modified Norwood procedure with new technique of anterograde regional cerebral perfusion (ARCeP and retrograde regional coronary perfusion (RRCoP in substitution of profound hypothermia and circulatory arrest in children with hypoplastic left heart syndrome (HLHS with extremely hypoplastic ascending aorta (HA. METHODS: In the period of

  17. Prediction of Cerebral Hyperperfusion Syndrome with Velocity Blood Pressure Index

    Directory of Open Access Journals (Sweden)

    Zhi-Chao Lai

    2015-01-01

    Full Text Available Background: Cerebral hyperperfusion syndrome is an important complication of carotid endarterectomy (CEA. An >100% increase in middle cerebral artery velocity (MCAV after CEA is used to predict the cerebral hyperperfusion syndrome (CHS development, but the accuracy is limited. The increase in blood pressure (BP after surgery is a risk factor of CHS, but no study uses it to predict CHS. This study was to create a more precise parameter for prediction of CHS by combined the increase of MCAV and BP after CEA. Methods: Systolic MCAV measured by transcranial Doppler and systematic BP were recorded preoperatively; 30 min postoperatively. The new parameter velocity BP index (VBI was calculated from the postoperative increase ratios of MCAV and BP. The prediction powers of VBI and the increase ratio of MCAV (velocity ratio [VR] were compared for predicting CHS occurrence. Results: Totally, 6/185 cases suffered CHS. The best-fit cut-off point of 2.0 for VBI was identified, which had 83.3% sensitivity, 98.3% specificity, 62.5% positive predictive value and 99.4% negative predictive value for CHS development. This result is significantly better than VR (33.3%, 97.2%, 28.6% and 97.8%. The area under the curve (AUC of receiver operating characteristic: AUC VBI = 0.981, 95% confidence interval [CI] 0.949-0.995; AUC VR = 0.935, 95% CI 0.890-0.966, P = 0.02. Conclusions: The new parameter VBI can more accurately predict patients at risk of CHS after CEA. This observation needs to be validated by larger studies.

  18. Contractile responses to ergotamine and dihydroergotamine in the perfused middle cerebral artery of rat

    DEFF Research Database (Denmark)

    Tfelt-Hansen, Peer; Nilsson, Elisabeth; Edvinsson, Lars

    2007-01-01

    mmHg and luminally perfused. All vessels used attained spontaneous contractile tone (34.9+/-1.8% of resting tone) and responded to luminal adenosine triphosphate (ATP) with dilatation (24.1+/-4.0%), which showed functioning endothelium. Luminally added ergotamine or DHE induced maximal contractions...... no significant effect. Using a myograph technique, isolated ring segments of the MCA with intact endothelium were mounted on two metal wires. Neither agonist caused relaxation of resting vessels, however, they both responded by weak contractile responses (26+/-3% of submaximal contractile capacity relative to 60...

  19. Wound healing in below-knee amputations in relation to skin perfusion pressure

    DEFF Research Database (Denmark)

    Holstein, P; Sager, P; Lassen, N A

    1979-01-01

    In 60 below-knee amputations the healing of the stumps was correlated with the local skin perfusion pressure (SPP) measured preoperatively as the external pressure required to stop isotope washout using 131I- or 125I--antipyrine mixed with histamine. Of the eight cases with an SPP below 20 mm......Hg, no less than six (75 per cent) failed to heal and required reamputation at the above-knee level. Of the 12 cases with an SPP between 20 and 30 mmHg four cases (33 per cent) failed to heal but of the 40 cases with an SPP above 30 mmHg, there were only four cases (10 per cent) which did not heal...... closely to the postoperative clinical course. We conclude that a low SPP can be used to predict ischaemic wound complications, leading to reamputation at a higher level....

  20. Wound healing in above-knee amputations in relation to skin perfusion pressure

    DEFF Research Database (Denmark)

    Holstein, P; Dovey, H; Lassen, N A

    1979-01-01

    In 59 above-knee amputations healing of the stumps was correlated with the local skin perfusion pressure (SPP) measured preoperatively as the external pressure required to stop isotope washout using 1318-- or 125I--antipyrine mixed with histamine. Out of the 11 cases with an SPP below 30 mm......Hg no less than nine (82 per cent) suffered severe wound complications. Out of the 48 cases with an SPP above 30 mmHg severe wound complications occurred in only four cases (8 per cent). The difference in wound complication rate is highly significant (P less than 0.01). The postoperative SPP measured...... on the stumps was on average only slightly and insignificantly higher than the preoperative values, explaining why the preoperative values related so closely to the postoperative clinical course. We conclude that the SPP can be used to predict ischaemic wound complications in above-knee amputations as has...

  1. [Alterations in cerebral perfusion in patients with systemic sclerosis and cognitive impairment].

    Science.gov (United States)

    Moreno-Gutiérrez, Juan; Coria-Moctezuma, Luis Alonso; del Pilar Cruz-Domínguez, María; Vera-Lastra, Olga Lidia

    2015-01-01

    Introducción: la esclerosis sistémica (ES) es una enfermedad autoinmune, sistémica, caracterizada por fibrosis, alteraciones inmunológicas y vasculares. La hipoperfusión cerebral puede ser causada por isquemia. Los trastornos cognitivos son causa importante de morbilidad. El objetivo de este estudio fue determinar la frecuencia de alteraciones en la perfusión cerebral (PC) en pacientes con ES y deterioro cognitivo (DC). Métodos: se estudiaron 88 pacientes con ES. A todos se les aplicó el Test de Montreal (TM) para evaluar el DC. A 15 pacientes con DC que cumplieron con los criterios (sin hipertensión arterial sistémica, diabetes mellitus, evento vascular cerebral, vasculitis, hipotiroidismo, depresión, sin ingesta de fármacos que interfieran con la evaluación cognitiva), se les midió la PC mediante Gamagrama Cerebral Perfusorio (GCP).Resultados: de los 88 pacientes con ES, 58 tuvieron DC con el TM. La PC se encontró disminuida en 12/15. La disminución de la PC se observó en los siguientes lóbulos (frontal en 9/15; temporal en 7/15, y parietal en 3/15. La concordancia entre el TM y GC fue 60 % para el lóbulo frontal, 46 % para el lóbulo temporal y 13 % parietal.Conclusiones: el DC es frecuente en la ES, la disminución de la PC fue más común en el lóbulo frontal, predominado en los pacientes de mayor edad y tiempo de evolución de la ES.

  2. Changes of cerebral hemodynamics in CT perfusion imaging of rabbit models with cerebral microembolism%兔脑微栓塞模型脑血流动力学的CT灌注动态变化

    Institute of Scientific and Technical Information of China (English)

    张放; 姚振威; 冯晓源; 孙华平

    2012-01-01

    目的 探讨兔脑微栓塞模型CT灌注成像(CT perfusion imaging,CTPI)脑血流动力学的动态变化规律.方法 30只新西兰兔,随机分成两组,A组:假手术对照组5只,B组:微栓塞组25只.经颈外动脉向颈内动脉注入直径约0.5 mm的SiO2颗粒10枚,分别于栓塞后30 min、3h、6h、12 h及24 h行CTPI,24 h处死动物取脑组织行HE染色.根据HE染色结果将模型分为缺血组和梗死组,分别观察其脑血流量(cerebral blood flow,CBF)、脑血容积(cerebral blood volume,CBV)和平均通过时间(mean transit time,MTT)的动态变化规律.结果 A组CTPI及HE染色均未见明显异常.B组3只因实验意外死亡,1只因下肢静脉穿刺失败导致CTPI失败,21只行CTPI,其中18只灌注异常,3只未见明显异常.18只灌注异常的兔中,HE染色10只脑梗死,7只脑缺血,1只未见明显异常.30 min时7只缺血兔脑不同程度低灌注,表现为CBF降低,MTT延长,CBV无显著变化,3~6h低灌注进一步加重,CBV值略降低,12h低灌注不同程度恢复,24 h进一步恢复.30 min时10只梗死兔脑明显低灌注,表现为CBF及CBV显著降低,MTT显著延长,3只兔低灌注分别在3h、6h及12 h不同程度恢复,然后下一时间又迅速降低并随着时间延长进一步加剧,其余7只兔低灌注程度随时间延长逐渐加剧或在一定水平上波动.结论 脑缺血3~6h低灌注最明显,12~ 24 h低灌注不同程度恢复,而脑梗死随时间延长低灌注程度不断加重或一过性恢复后再次加重.脑缺血的特征是CBF和CBV的不匹配,缺血组织CBF显著降低,CBV无显著变化,而脑梗死则表现为这两个参数的一致性下降.%Objective To study the changes of cerebral hemodynamics revealed by CT perfusion imaging ( CTPI) in rabbit models of cerebral microembolism. Methods Thirty normal New Zealand rabbits were randomly divided into two groups; Group A (n =5) underwent sham operation, group B (n =25) underwent an operation of microembolism

  3. Detection of misery perfusion in the cerebral hemisphere with chronic unilateral major cerebral artery steno-occlusive disease using crossed cerebellar hypoperfusion: comparison of brain SPECT and PET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Yoshiyasu; Ogasawara, Kuniaki; Saito, Hideo; Takahashi, Yoshihiro; Ogasawara, Yasushi; Kobayashi, Masakazu; Ogawa, Akira [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Iwate Medical University, Cyclotron Research Center, Morioka (Japan); Terasaki, Kazunori [Iwate Medical University, Cyclotron Research Center, Morioka (Japan); Yoshida, Kenji; Beppu, Takaaki; Kubo, Yoshitaka; Fujiwara, Shunrou [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Tsushima, Eiki [Hirosaki University, Graduate School of Health Sciences, Hirosaki (Japan)

    2013-10-15

    In patients with unilateral internal carotid or middle cerebral artery (ICA or MCA) occlusive disease, the degree of crossed cerebellar hypoperfusion that is evident within a few months after the onset of stroke may reflect cerebral metabolic rate of oxygen in the affected cerebral hemisphere relative to that in the contralateral cerebral hemisphere. The aim of the present study was to determine whether the ratio of blood flow asymmetry in the cerebellar hemisphere to blood flow asymmetry in the cerebral hemisphere on positron emission tomography (PET) and single photon emission computed tomography (SPECT) correlates with oxygen extraction fraction (OEF) asymmetry in the cerebral hemisphere on PET in patients with chronic unilateral ICA or MCA occlusive disease and whether this blood flow ratio on SPECT detects misery perfusion in the affected cerebral hemisphere in such patients. Brain blood flow and OEF were assessed using {sup 15}O-PET and N-isopropyl-p-[{sup 123}I]iodoamphetamine ({sup 123}I-IMP) SPECT, respectively. All images were anatomically standardized using SPM2. A region of interest (ROI) was automatically placed in the bilateral MCA territories and in the bilateral cerebellar hemispheres using a three-dimensional stereotaxic ROI template, and affected-to-contralateral asymmetry in the MCA territory or contralateral-to-affected asymmetry in the cerebellar hemisphere was calculated. Sixty-three patients with reduced blood flow in the affected cerebral hemisphere on {sup 123}I-IMP SPECT were enrolled in this study. A significant correlation was observed between MCA ROI asymmetry of PET OEF and the ratio of cerebellar hemisphere asymmetry of blood flow to MCA ROI asymmetry of blood flow on PET (r = 0.381, p = 0.0019) or SPECT (r = 0.459, p = 0.0001). The correlation coefficient was higher when reanalyzed in a subgroup of 43 patients undergoing a PET study within 3 months after the last ischemic event (r = 0.541, p = 0.0001 for PET; r = 0.609, p < 0

  4. Expansion duroplasty improves intraspinal pressure, spinal cord perfusion pressure, and vascular pressure reactivity index in patients with traumatic spinal cord injury: injured spinal cord pressure evaluation study.

    Science.gov (United States)

    Phang, Isaac; Werndle, Melissa C; Saadoun, Samira; Varsos, Georgios; Czosnyka, Marek; Zoumprouli, Argyro; Papadopoulos, Marios C

    2015-06-15

    We recently showed that, after traumatic spinal cord injury (TSCI), laminectomy does not improve intraspinal pressure (ISP), spinal cord perfusion pressure (SCPP), or the vascular pressure reactivity index (sPRx) at the injury site sufficiently because of dural compression. This is an open label, prospective trial comparing combined bony and dural decompression versus laminectomy. Twenty-one patients with acute severe TSCI had re-alignment of the fracture and surgical fixation; 11 had laminectomy alone (laminectomy group) and 10 had laminectomy and duroplasty (laminectomy+duroplasty group). Primary outcomes were magnetic resonance imaging evidence of spinal cord decompression (increase in intradural space, cerebrospinal fluid around the injured cord) and spinal cord physiology (ISP, SCPP, sPRx). The laminectomy and laminectomy+duroplasty groups were well matched. Compared with the laminectomy group, the laminectomy+duroplasty group had greater increase in intradural space at the injury site and more effective decompression of the injured cord. In the laminectomy+duroplasty group, ISP was lower, SCPP higher, and sPRx lower, (i.e., improved vascular pressure reactivity), compared with the laminectomy group. Laminectomy+duroplasty caused cerebrospinal fluid leak that settled with lumbar drain in one patient and pseudomeningocele that resolved completely in five patients. We conclude that, after TSCI, laminectomy+duroplasty improves spinal cord radiological and physiological parameters more effectively than laminectomy alone.

  5. Perfusão da artéria pulmonar não melhora os índices de fator natriurético cerebral (BNP em estudo experimental em suínos Pulmonary artery perfusion does not improve brain natriuretic peptide (BNP levels in suine experimental research

    Directory of Open Access Journals (Sweden)

    Edmo Atique Gabriel

    2010-12-01

    Full Text Available OBJETIVO: Avaliar se perfusão controlada do tronco pulmonar durante circulação extracorpórea (CEC modifica os níveis de BNP expressos pelo miocárdio ventricular. MÉTODOS: Estudo experimental com 32 porcos, divididos em dois grupos de acordo com estratégia de CEC - grupo I (cardioplegia e grupo II (coração batendo. Ambos os grupos foram alocados em três subgrupos, de acordo com a estratégia de perfusão pulmonar - subgrupo A (controle: sem perfusão pulmonar, subgrupo B (perfusão pulmonar com sangue arterial e subgrupo C (perfusão com sangue venoso. Nos subgrupos B e C, pulmões foram perfundidos por 30 minutos, utilizando pressão arterial média pulmonar (PAPM préoperatória como pressão de perfusão, a qual foi controlada com manômetro. PAPM e resistência vascular pulmonar (RVP foram medidas após saída de CEC com cateter de Swan-Ganz. No período pré-operatório e após 30 minutos de perfusão pulmonar, fragmentos de miocárdio ventricular direito foram coletados para avaliar expressão de peptídeo natriurético cerebral (BNP e padrão histológico tecidual. Técnicas de imunohistoquímica e hematoxilina-eosina foram utilizadas para determinar, respectivamente, expressão de BNP e lesões inflamatórias miocárdicas. RESULTADOS: Nos animais submetidos à perfusão controlada do tronco pulmonar, houve redução pós-operatória da PAPM (P=0,03 e da RVP (P=0,005. Não houve diferenças entre os subgrupos do grupo I (P=0,228 e subgrupos do grupo II (P=0,325 quanto à expressão pós-operatória de BNP. Não houve diferenças entre subgrupos com e sem perfusão pulmonar quanto à intensidade das lesões inflamatórias miocárdicas identificadas no pós-operatório (P>0,05. CONCLUSÃO: Perfusão controlada do tronco pulmonar por 30 minutos não foi suficiente para promover alterações substanciais na expressão de BNP e no padrão histológico miocárdico do ventrículo direito.OBJECTIVE: Assess if the main pulmonary artery

  6. SPECT imaging of GABA{sub A}/benzodiazepine receptors and cerebral perfusion in mild cognitive impairment

    Energy Technology Data Exchange (ETDEWEB)

    Pappata, Sabina; Varrone, Andrea; Vicidomini, Caterina; Sansone, Valeria; Comerci, Marco; Panico, Maria Rosaria; Quarantelli, Mario [CNR, Institute of Biostructure and Bioimaging, Naples (Italy); Milan, Graziella; De Falco, Caterina; Lore, Elisa; Postiglione, Alfredo [University ' ' Federico II' ' , Department of Clinical and Experimental Medicine, Naples (Italy); Iavarone, Alessandro [Neurologic and Stroke Unit, CTO Hospital, Naples (Italy); Salvatore, Marco [CNR, Institute of Biostructure and Bioimaging, Naples (Italy); University ' ' Federico II' ' , Department of Biomorphological and Functional Sciences, Naples (Italy)

    2010-06-15

    The involvement of neocortical and limbic GABA{sub A}/benzodiazepine (BZD) receptors in Alzheimer's disease (AD) is controversial and mainly reported in advanced stages. The status of these receptors in the very early stages of AD is unclear and has not been explored in vivo. Our aims were to investigate in vivo the integrity of cerebral cortical GABA{sub A}/BZD receptors in subjects with amnestic mild cognitive impairment (MCI) and to compare possible receptor changes to those in cerebral perfusion. [{sup 123}I]Iomazenil and [{sup 99m}Tc]HMPAO SPECT images were acquired in 16 patients with amnestic MCI and in 14 normal elderly control subjects (only [{sup 123}I]iomazenil imaging in 5, only [{sup 99m}Tc]HMPAO imaging in 4, and both [{sup 123}I]iomazenil and [{sup 99m}Tc]HMPAO imaging in 5). Region of interest (ROI) analysis and voxel-based analysis were performed with cerebellar normalization. Neither ROI analysis nor voxel-based analysis showed significant [{sup 123}I]iomazenil binding changes in MCI patients compared to control subjects, either as a whole group or when considering only those patients with MCI that converted to AD within 2 years of clinical follow-up. In contrast, the ROI analysis revealed significant hypoperfusion of the precuneus and posterior cingulate cortex in the whole group of MCI patients and in MCI converters as compared to control subjects. Voxel-based analysis showed similar results. These results indicate that in the very early stages of AD, neocortical and limbic neurons/synapses expressing GABA{sub A}/BZD receptors are essentially preserved. They suggest that in MCI patients functional changes precede neuronal/synaptic loss in neocortical posterior regions and that [{sup 99m}Tc]HMPAO rCBF imaging is more sensitive than [{sup 123}I]iomazenil GABA{sub A}/BZD receptor imaging in detecting prodromal AD. (orig.)

  7. Wavelet-based calculation of cerebral angiographic data from time-resolved CT perfusion acquisitions

    Energy Technology Data Exchange (ETDEWEB)

    Havla, Lukas; Dietrich, Olaf [Ludwig-Maximilians-University Hospital Munich, Josef-Lissner-Laboratory for Biomedical Imaging, Institute for Clinical Radiology, Munich (Germany); Thierfelder, Kolja M.; Beyer, Sebastian E.; Sommer, Wieland H. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany)

    2015-08-15

    To evaluate a new approach for reconstructing angiographic images by application of wavelet transforms on CT perfusion data. Fifteen consecutive patients with suspected stroke were examined with a multi-detector CT acquiring 32 dynamic phases (∇t = 1.5s) of 99 slices (total slab thickness 99mm) at 80kV/200mAs. Thirty-five mL of iomeprol-350 was injected (flow rate = 4.5mL/s). Angiographic datasets were calculated after initial rigid-body motion correction using (a) temporally filtered maximum intensity projections (tMIP) and (b) the wavelet transform (Paul wavelet, order 1) of each voxel time course. The maximum of the wavelet-power-spectrum was defined as the angiographic signal intensity. The contrast-to-noise ratio (CNR) of 18 different vessel segments was quantified and two blinded readers rated the images qualitatively using 5pt Likert scales. The CNR for the wavelet angiography (501.8 ± 433.0) was significantly higher than for the tMIP approach (55.7 ± 29.7, Wilcoxon test p < 0.00001). Image quality was rated to be significantly higher (p < 0.001) for the wavelet angiography with median scores of 4/4 (reader 1/reader 2) than the tMIP (scores of 3/3). The proposed calculation approach for angiography data using temporal wavelet transforms of intracranial CT perfusion datasets provides higher vascular contrast and intrinsic removal of non-enhancing structures such as bone. (orig.)

  8. Long-term effects of cerebral hypoperfusion on neural density and function using misery perfusion animal model.

    Science.gov (United States)

    Nishino, Asuka; Tajima, Yosuke; Takuwa, Hiroyuki; Masamoto, Kazuto; Taniguchi, Junko; Wakizaka, Hidekatsu; Kokuryo, Daisuke; Urushihata, Takuya; Aoki, Ichio; Kanno, Iwao; Tomita, Yutaka; Suzuki, Norihiro; Ikoma, Yoko; Ito, Hiroshi

    2016-04-27

    We investigated the chronic effects of cerebral hypoperfusion on neuronal density and functional hyperemia using our misery perfusion mouse model under unilateral common carotid artery occlusion (UCCAO). Neuronal density evaluated 28 days after UCCAO using [(11)C]flumazenil-PET and histology indicated no neurologic deficit in the hippocampus and neocortex. CBF response to sensory stimulation was assessed using laser-Doppler flowmetry. Percentage changes in CBF response of the ipsilateral hemisphere to UCCAO were 18.4 ± 3.0%, 6.9 ± 2.8%, 6.8 ± 2.3% and 4.9 ± 2.4% before, and 7, 14 and 28 days after UCCAO, respectively. Statistical significance was found at 7, 14 and 28 days after UCCAO (P < 0.01). Contrary to our previous finding (Tajima et al. 2014) showing recovered CBF response to hypercapnia on 28 days after UCCAO using the same model, functional hyperemia was sustained and became worse 28 days after UCCAO.

  9. The relation of regional cerebral perfusion and atrophy in mild cognitive impairment (MCI) and early Alzheimer's dementia.

    Science.gov (United States)

    Luckhaus, Christian; Cohnen, Mathias; Flüss, Michael Oliver; Jänner, Michaela; Grass-Kapanke, Brigitte; Teipel, Stefan J; Grothe, Michel; Hampel, Harald; Peters, Oliver; Kornhuber, Johannes; Maier, Wolfgang; Supprian, Tillmann; Gaebel, Wolfgang; Mödder, Ulrich; Wittsack, Hans-Jörg

    2010-07-30

    The spatial and temporal relations between regional cerebral blood flow (rCBF) and brain volume (rVOL) changes in incipient and early Alzheimer's dementia (AD) are not fully understood. The participants comprised 30 subjects with mild cognitive impairment (MCI) and 15 with mild AD who were examined using structural and perfusion-weighted magnetic resonance imaging (MRI) at 1.5 Tesla. Hippocampus and amygdala volumes were measured by manual volumetry. A region-of-interest co-localisation method was used to calculate rCBF values. DNA samples were genotyped for apolipoprotein E (APO E). In comparisons of AD with MCI, rCBF was reduced in the posterior cingulum only, while profound rVOL reductions occurred in both right and left amygdala and in the right hippocampus, and as a trend, in the left hippocampus. Brain volumes of the hippocampus and the amygdala were uncorrelated with the respective rCBF variables in both MCI and AD. Hippocampal but not amygdalar volumes were associated with presence of one or two APOE epsilon4 alleles in MCI and mild AD, while there was no association of APOE epsilon4 allele with rCBF. These data support earlier indications that rCBF and rVOL changes are at least partly dissociated in the early pathogenesis of AD and heterogeneously associated with the APOE risk allele. The data also support the concept of functional compensatory brain activation and the diaschisis hypothesis as relevant in incipient and early AD.

  10. Technetium-99m d,l-HM-PAO: a new radiopharmaceutical for SPECT imaging of regional cerebral blood perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Neirinckx, R.D.; Canning, L.R.; Piper, I.M.; Nowotnik, D.P.; Pickett, R.D.; Holmes, R.A.; Volkert, W.A.; Forster, A.M.; Weisner, P.S.; Marriott, J.A.

    1987-02-01

    Following investigation of a large number of new ligands based upon propylene amine oxime (PnAO) the d,l-diastereoisomer of hexamethyl propyleneamine oxime (HM-PAO) was selected as the preferred ligand for 99mTc as a tracer for cerebral perfusion imaging. The neutral, lipophilic 99mTc complex of d,l-HM-PAO was formed in high yield by stannous reduction of 99Mo/99mTc generator eluate using a kit formulation of the ligand. Two minutes following i.v. administration of this complex in rats, 2.25% of the injected dose appears in the brain. Little washout of the tracer is observed up to 24 hr postinjection. By qualitative autoradiographic comparison with iodoantipyrine this new radiopharmaceutical displays blood flow dependent brain uptake with little redistribution of the tracer over time. The lipophilic 99mTc complex converts slowly in vitro to a secondary complex. This conversion process may account for the ability of (99mTc)d,l-HM-PAO to be retained within the brain without redistribution.

  11. [Abnormal cerebral blood flow distributions during the post-ictal phase of febrile status epilepticus in three pediatric patients measured by arterial spin labeling perfusion MRI].

    Science.gov (United States)

    Hirano, Keiko; Fukuda, Tokiko

    2016-05-01

    The ability to visualize brain perfusion is important for identifying epileptic foci. We present three pediatric cases showing asymmetrical cerebral blood flow (CBF) distributions during the post-ictal phase of febrile status epilepticus measured by arterial spin labeling (ASL) perfusion MRI. During the acute phase, regional CBF measurements in the areas considered including epileptic foci were higher than in the corresponding area of the contralateral hemisphere, though the exact quantitative value varied between cases. We could not identify the correct epileptogenic foci, because those ASL images were taken after the prolonged and extraordinary activation of neurons in the affected area. During the recovery phase, the differences reduced and the average regional CBF measurement was 54.6 ± 6.1 ml/100 g per minute, which was a little less than the number of previous ASL studies. ASL perfusion MRI imaging provides a method for evaluating regional CBF by using magnetically labeled arterial blood water as an endogenous tracer. With this technique, we can repeatedly evaluate both the brain structure and the level of perfusion at the same time. ASL is noninvasive and easily accessible, and therefore it could become a routine tool for assessment of perfusion in daily practice of pediatric neurology.

  12. Clinical Application of CT Cerebral Perfusion and Angiography in Acute Cerebral Infarction%CT脑灌注与血管造影在急性脑梗死中的临床应用

    Institute of Scientific and Technical Information of China (English)

    娄雪磊

    2015-01-01

    目的:探讨CT脑灌注与血管造影在急性脑梗死中的临床应用效果。方法选择医院2014年12月~2015年6月诊治的急性脑梗死患者中抽取75例作研究对象,对其分别进行CT脑灌注和血管造影检查,对比两种检查方法的诊断情况。结果 CT灌注图内,对应患者的临床症状的灌注异常处有63例,其阳性率是84.0%,高于CT检测的19例,其阳性率是25.3%(P<0.05);同时,经CT脑灌注和血管造影检测发现,责任血管者采取CT脑灌注检测阳性者48例,其阳性率是64.0%,无责任血管者13例,其阳性率是17.3%(P<0.05)。结论 CT脑灌注与血管造影在急性脑梗死中的临床应用效果确切,有助于为急性脑梗死预防、治疗措施的制定提供参考依据。%Objective To study the clinical application effect of CT cerebral perfusion with angiography in acute cerebral infarction.Methods In a hospital in December 2014 to June 2015 in the diagnosis and treatment of acute cerebral infarction patients from 75 cases as the research object,the CT cerebral perfusion and angiography respectively,compared to two kinds of inspection methods of diagnosis.ResultsCT perfusion in the figure, the corresponding clinical symptoms in patients with perfusion abnormalities in 63 cases,the positive rate was 84.0%,significantly higher than that of CT detection of 19 cases,the positive rate was 25.3%(P<0.05,at the same time,CT cerebral perfusion and angiographic examination found that responsibility vessels take CT cerebral perfusion was 48 cases,the positive rate was 64.0%,significantly less responsibility 13 cases of blood vessels,the positive rate was 17.3%(P<0.05). ConclusionCT cerebral perfusion with angiography in acute cerebral infarction clinical application effect of precise,help for acute cerebral infarction,to provide the reference basis for the establishment of prevention and treatment measures.

  13. Closed-loop controller for chest compressions based on coronary perfusion pressure: a computer simulation study.

    Science.gov (United States)

    Wang, Chunfei; Zhang, Guang; Wu, Taihu; Zhan, Ningbo; Wang, Yaling

    2016-03-01

    High-quality cardiopulmonary resuscitation contributes to cardiac arrest survival. The traditional chest compression (CC) standard, which neglects individual differences, uses unified standards for compression depth and compression rate in practice. In this study, an effective and personalized CC method for automatic mechanical compression devices is provided. We rebuild Charles F. Babbs' human circulation model with a coronary perfusion pressure (CPP) simulation module and propose a closed-loop controller based on a fuzzy control algorithm for CCs, which adjusts the CC depth according to the CPP. Compared with a traditional proportion-integration-differentiation (PID) controller, the performance of the fuzzy controller is evaluated in computer simulation studies. The simulation results demonstrate that the fuzzy closed-loop controller results in shorter regulation time, fewer oscillations and smaller overshoot than traditional PID controllers and outperforms the traditional PID controller for CPP regulation and maintenance.

  14. Cerebral perfusion differences in women currently with and recovered from anorexia nervosa.

    Science.gov (United States)

    Sheng, Min; Lu, Hanzhang; Liu, Peiying; Thomas, Binu P; McAdams, Carrie J

    2015-05-30

    Anorexia nervosa is a serious psychiatric disorder characterized by restricted eating, a pursuit of thinness, and altered perceptions of body shape and size. Neuroimaging in anorexia nervosa has revealed morphological and functional alterations in the brain. A better understanding of physiological changes in anorexia nervosa could provide a brain-specific health marker relevant to treatment and outcomes. In this study, we applied several advanced magnetic resonance imaging (MRI) techniques to quantify regional and global cerebral blood flow (CBF) in 25 healthy women (HC), 23 patients currently with anorexia (AN-C) and 19 patients in long-term weight recovery following anorexia (AN-WR). Specifically, CBF was measured with pseudo-continuous arterial spin labeling (pCASL) MRI and then verified by a different technique, phase contrast (PC) MRI. Venous T2 values were determined by T2 relaxation under spin tagging (TRUST) MRI, and were used to corroborate the CBF results. These novel techniques were implemented on a standard 3T MRI scanner without any exogenous tracers, and the total scan duration was less than 10min. Voxel-wise comparison revealed that the AN-WR group showed lower CBF in bilateral temporal and frontal lobes than the AN-C group. Compared with the HC group, the AN-C group also showed higher CBF in the right temporal lobe. Whole-brain-averaged CBF was significantly decreased in the AN-WR group compared with the AN-C group, consistent with the PC-MRI results. Venous T2 values were lower in the AN-WR group than in the AN-C group, consistent with the CBF results. A review of prior work examining CBF in anorexia nervosa is included in the discussion. This study identifies several differences in the cerebral physiological alterations in anorexia nervosa, and finds specific differences relevant to the current state of the disorder.

  15. The Effect of Milrinone on Splanchnic and Cerebral Perfusion in Infants With Congenital Heart Disease Prior to Surgery: An Observational Study.

    Science.gov (United States)

    Bianchi, Maria Otilia; Cheung, Po-Yin; Phillipos, Ernest; Aranha-Netto, Abimael; Joynt, Chloe

    2015-08-01

    Despite the advancement in the postoperative care of neonates with congenital heart disease (CHD), there is little information on preoperative management of systemic and regional hemodynamics, which may be related to outcomes. We aimed to determine the preoperative effect of milrinone, a phosphodiesterase III inhibitor, on cardiac output and splanchnic and cerebral perfusion in neonates with CHD. Neonates with CHD requiring cardiac surgery were enrolled in a prospective, single-blinded study once a clinical decision of starting milrinone (0.75 μg/kg per minute intravenously) using institutional criteria was made. Demographic and clinical variables and outcomes were recorded. Combined cardiac output and measures of splanchnic (superior mesenteric and celiac arteries) and cerebral (anterior and middle cerebral arteries) perfusion were determined by Doppler studies at 0, 6, 24, and 48 h after milrinone infusion. Investigators were unaware of intervention time points and patients in analyzing blood flow measurements. Seventeen term (39.2 ± 1.3 weeks) neonates were included with hypoplastic left-sided heart syndrome (78.5%) as the most common diagnosis. Combined cardiac output increased by 28% within 48 h (613 ± 154 vs. 479 ± 147 mL/kg per minute at baseline, P mean velocity increased at 6 h and throughout 48 h of milrinone infusion (P mean velocities at cerebral arteries increased with milrinone infusion (P < 0.05~0.08), and the corresponding changes at celiac artery were modest. There were no significant changes in splanchnic and cerebral resistive and pulsatility indices during milrinone infusion. Milrinone increases cardiac output with concurrent effects on splanchnic and cerebral blood flows during the short-term preoperative use in neonates with CHD.

  16. Estimation of cerebral vascular tone during exercise; evaluation by critical closing pressure in humans

    DEFF Research Database (Denmark)

    Ogoh, Shigehiko; Brothers, R Matthew; Jeschke, Monica;

    2010-01-01

    The aim of the present study was to calculate critical closing pressure (CCP) of the cerebral vasculature at rest and during exercise to estimate cerebral vascular tone. Five men and two women were seated upright for 15 min and then performed 15 min of right-legged knee extension exercise at 40, 60...... and 75% of their maximal workload (WL(max)). Middle cerebral artery blood velocity (MCA V) and blood pressure in the radial artery were recorded. The CCP was calculated by linear extrapolation from 1 min recordings of pairs of systolic and diastolic pressure and MCA V waveforms from both the right...

  17. Regional cerebral blood flow autoregulation in patients with fulminant hepatic failure

    DEFF Research Database (Denmark)

    Larsen, Fin Stolze; Strauss, Gitte Irene; Møller, Kirsten;

    2000-01-01

    The absence of cerebral blood flow autoregulation in patients with fulminant hepatic failure (FHF) implies that changes in arterial pressure directly influence cerebral perfusion. It is assumed that dilatation of cerebral arterioles is responsible for the impaired autoregulation. Recently, frontal...... blood flow was reported to be lower compared with other brain regions, indicating greater arteriolar tone and perhaps preserved regional cerebral autoregulation. In patients with severe FHF (6 women, 1 man; median age, 46 years; range, 18 to 55 years), we tested the hypothesis that perfusion...... in the anterior cerebral artery would be less affected by an increase in mean arterial pressure compared with the brain area supplied by the middle cerebral artery. Relative changes in cerebral perfusion were determined by transcranial Doppler-measured mean flow velocity (V(mean)), and resistance was determined...

  18. The evolution of the cerebral blood volume abnormality in patients with ischemic stroke: a CT perfusion study

    Energy Technology Data Exchange (ETDEWEB)

    D' Esterre, Christopher D.; Lee, Ting Yim (Lawson Health Research Inst., London (Canada); Robarts Research Inst., London (Canada)), email: tlee@robarts.ca; Aviv, Richard I. (Sunnybrook Health Sciences Centre, Toronto (Canada))

    2012-05-15

    Background: Accurate identification of the acute infarct core abnormality is important for guiding acute stroke treatment. Abnormality volumes from diffusion-weighted MRI (DWI) and CT perfusion (CTP)-cerebral blood volume (CBV) are highly correlated. DWI lesions have been shown to be reversible at 24 h. Purpose: To examine the temporal profile of the CT perfusion (CTP)-derived CBV abnormality out to 7 days post ischemic stroke. Material and Methods: Twenty-six patients were included. Group A (n = 13) underwent a noncontrast CT (NCCT), CTP/CT angiography (CTA) within 6 h of stroke onset, CTP/CTA at 24 h, and CTP/NCCT at 5-7 days post stroke. Group B (n = 13) underwent a NCCT, CTP/CTA within 6 h of stroke onset, and NCCT at 5-7 days. Recanalization status was established in all patients. For both groups, infarct volumes were traced on 5-7 day NCCT images and superimposed onto all CTP-CBV functional maps to determine CBV. Group B (n = 13) admission images were used to define CBV infarct thresholds for gray and white matter. CBV-lesion overestimation was determined for Group A using the thresholds from Group B. Results: CBV (ml x 100g- 1; mean +- stdev) for gray/white matter, within confirmed infarcted regions (CBVI) at admission, 24 h, and 5-7 days were 1.82 +- 0.56, 1.56 +- 0.42, 1.75 +- 0.31, and 1.38 +- 0.65, 1.13 +- 0.31, 1.32 +- 0.44, respectively, when averaged over all patients (P > 0.05). Four patients had tissue time-density curves from ischemic lesions (TDCi) with an incomplete contrast medium wash-out phase (truncation) at admission and/or 24 h. Compared to admission, gray matter CBVI was higher at 5-7 days for patients with TDCi truncation (P < 0.05). There were no significant CBVI increases for the eight patients without truncation (P > 0.05). Over-estimation of acute CBV lesion was present in 3/4 (75%) and 1/9 (11%) of patients with/without TDCi truncation, respectively. Conclusion: CTP-derived CBV lesion reversal is associated with TDCi truncation

  19. [The peripheral perfusion pressure: a new non-invasive parameter for the circulatory monitoring of patients (author's transl)].

    Science.gov (United States)

    Huch, A; Lübbers, D W; Huch, R

    1975-01-01

    Heating of a skin area to a temperature of 42 degrees to 44 degrees C produces a certain physiological condition which induces maximal vasodilatation. Detailed experiments have shown that local peripheral vascular resistance of such an area remains constant for several hours. The flow in this area is proportional to the actual perfusion pressure. Relative flow was measured by means of a new type of electrode fixed to the skin like and ECG electrode, and compared with simultaneous intra-arterial blood pressure measruements. The changes in arterial blood pressure were also recorded by the skin electrode. This new parameter is defined as "peripheral perfusion pressure". It is appropiate for non-invasive continuous monitoring of the circulatory system of patients.

  20. Cerebral perfusion in the predementia stages of Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Binnewijzend, Maja A.A.; Wattjes, Mike P.; Berckel, Bart N.M. van; Barkhof, Frederik [VU University Medical Center, Department of Radiology and Nuclear Medicine, Neuroscience Campus Amsterdam, Alzheimercenter Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Benedictus, Marije R.; Prins, Niels D.; Scheltens, Philip [VU University Medical Center, Department of Neurology, Neuroscience Campus Amsterdam, Alzheimer Center Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Kuijer, Joost P.A. [VU University Medical Center, Department of Physics and Medical Technology, Neuroscience Campus Amsterdam, Alzheimer Center Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Flier, Wiesje M. van der [VU University Medical Center, Department of Neurology, Neuroscience Campus Amsterdam, Alzheimer Center Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); VU University Medical Center, Department of Epidemiology and Biostatistics Neuroscience Campus Amsterdam, Alzheimer Center Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Teunissen, Charlotte E. [VU University Medical Center, Department of Clinical Chemistry, Neuroscience Campus Amsterdam, Alzheimer Center Amsterdam, P.O. Box 7057, Amsterdam (Netherlands)

    2016-02-15

    To investigate arterial spin-labelling (ASL) cerebral blood flow (CBF) changes in predementia stages of Alzheimer's disease (AD). Data were obtained from 177 patients with subjective complaints, mild cognitive impairment and AD from the Amsterdam Dementia Cohort. AD stages were based on diagnosis and cerebrospinal fluid biomarkers amyloid-β (Aβ) and total-tau (tau). General-linear-models were used to assess relationships between AD stages and total and regional CBF, correcting for age and sex. Decreasing CBF was related to more advanced AD stages in all supratentorial regions (p for trend < 0.05). Post-hoc testing revealed that CBF was lower in AD compared to controls and stage-1 predementia patients (i.e. abnormal Aβ and normal tau) in temporal and parietal regions, and compared to stage-2 predementia patients (i.e. abnormal Aβ and tau) in temporal regions. CBF values of stage-2 predementia patients were numerically in between those of stage-1 predementia patients and AD. The continuing decrease of CBF along the continuum of AD indicates the potential of ASL-CBF as a measure for disease progression. (orig.)

  1. Cerebral perfusion and glucose metabolism in Alzheimer's disease and frontotemporal dementia: two sides of the same coin?

    Energy Technology Data Exchange (ETDEWEB)

    Verfaillie, Sander C.J.; Adriaanse, Sofie M.; Binnewijzend, Maja A.A.; Benedictus, Marije R.; Ossenkoppele, Rik [VU University Medical Centre, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands); VU University Medical Centre, Alzheimer Centre and Department of Neurology, P.O. Box 7057, Amsterdam (Netherlands); Wattjes, Mike P.; Lammertsma, Adriaan A.; Boellaard, Ronald; Berckel, Bart N.M. van; Barkhof, Frederik [VU University Medical Centre, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands); Pijnenburg, Yolande A.L.; Scheltens, Philip [VU University Medical Centre, Alzheimer Centre and Department of Neurology, P.O. Box 7057, Amsterdam (Netherlands); Flier, Wiesje M. van der [VU University Medical Centre, Alzheimer Centre and Department of Neurology, P.O. Box 7057, Amsterdam (Netherlands); VU University Medical Centre, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands); Kuijer, Joost P.A. [VU University Medical Centre, Department of Physics and Medical Technology, Amsterdam (Netherlands)

    2015-10-15

    Alzheimer's disease (AD) and frontotemporal (FTD) dementia can be differentiated using [{sup 18}F]-2-deoxy-2-fluoro-D-glucose (FDG)-PET. Since cerebral blood flow (CBF) is related to glucose metabolism, our aim was to investigate the extent of overlap of abnormalities between AD and FTD. Normalized FDG-PET and arterial spin labelling (ASL-MRI)-derived CBF was measured in 18 AD patients (age, 64 ± 8), 12 FTD patients (age, 61 ± 8), and 10 controls (age, 56 ± 10). Voxel-wise comparisons, region-of-interest (ROI), correlation, and ROC curve analyses were performed. Voxel-wise comparisons showed decreased CBF and FDG uptake in AD compared with controls and FTD in both precuneus and inferior parietal lobule (IPL). Compared with controls and AD, FTD patients showed both hypometabolism and hypoperfusion in medial prefrontal cortex (mPFC). ASL and FDG were related in precuneus (r = 0.62, p < 0.001), IPL (r = 0.61, p < 0.001), and mPFC across groups (r = 0.74, p < 001). ROC analyses indicated comparable performance of perfusion and metabolism in the precuneus (AUC, 0.72 and 0.74), IPL (0.85 and 0.94) for AD relative to FTD, and in the mPFC in FTD relative to AD (both 0.68). Similar patterns of hypoperfusion and hypometabolism were observed in regions typically associated with AD and FTD, suggesting that ASL-MRI provides information comparable to FDG-PET. (orig.)

  2. Cardiopulmonary fitness correlates with regional cerebral grey matter perfusion and density in men with coronary artery disease.

    Directory of Open Access Journals (Sweden)

    Bradley J MacIntosh

    Full Text Available PURPOSE: Physical activity is associated with positive effects on the brain but there is a paucity of clinical neuroimaging data in patients with coronary artery disease (CAD, a cardiovascular condition associated with grey matter loss. The purpose of this study was to determine which brain regions are impacted by cardiopulmonary fitness and with the change in fitness after 6 months of exercise-based cardiac rehabilitation. METHODS: CAD patients underwent magnetic resonance imaging at baseline, and peak volume of oxygen uptake during exercise testing (VO2Peak was measured at baseline and after 6 months of training. T1-weighted structural images were used to perform grey matter (GM voxel-based morphometry (VBM. Pseudo-continuous arterial spin labeling (pcASL was used to produce cerebral blood flow (CBF images. VBM and CBF data were tested voxel-wise using VO2Peak and age as explanatory variables. RESULTS: In 30 men with CAD (mean age 65±7 years, VBM and CBF identified 7 and 5 respective regions positively associated with baseline VO2Peak. These included the pre- and post-central, paracingulate, caudate, hippocampal regions and converging findings in the putamen. VO2Peak increased by 20% at follow-up in 29 patients (t = 9.6, df = 28, p<0.0001. Baseline CBF in the left post-central gyrus and baseline GM density in the right putamen predicted greater change in VO2Peak. CONCLUSION: Perfusion and GM density were associated with fitness at baseline and with greater fitness gains with exercise. This study identifies new neurobiological correlates of fitness and demonstrates the utility of multi-modal MRI to evaluate the effects of exercise in CAD patients.

  3. Effects of regional cerebral blood flow perfusion on learning and memory function and its molecular mechanism in rats

    Institute of Scientific and Technical Information of China (English)

    Cunli Xu; Wenhua Wu; Lingbin Kong

    2016-01-01

    Objective:To study the effects of regional cerebral blood flow (rCBF) perfusion on learning and memory function in special brain areas and its molecular mechanism in rat. Methods: Sixty-four adult male healthy Sprague-Dawley (SD) rats were randomly divided into two groups: Afalse operation group and an operation group. The false operation group was randomly divided into four subgroups (A0, B0, C0, and D0) and the operation group was randomly divided into four subgroups (A, B, C, and D), with eight rats in each subgroup. The operation group underwent bilateral common carotid artery permanent ligation, while the other group only underwent a skin incision without the bilateral common carotid artery permanent ligation. Learning memory function of rats in each subgroup was measured using a Y-maze at 4 h, 8 h, 24 h, and 3 days after surgery. The rCBF in the right frontal lobe and hippocampus was detected using the Periflux PF model laser Doppler flowmetry and c-fos, c-jun, Bcl-2, and Bax protein expression in the right frontal lobe and hippocampus was measured using immunohistochemistry. Results: The rCBF in the right frontal lobule division and right hippocampus division was significantly lower in the operation group than in the false operation group (P Conclusions:rCBF decrease can impair learning and memory function in rats, which may be related to the increased expression of c-fos, c-jun, Bcl-2, and Bax proteins in the frontal cortex and hippocampus.

  4. Contralateral Hypoplastic Venous Draining Sinuses Are Associated with Elevated Intracranial Pressure in Unilateral Cerebral Sinovenous Thrombosis.

    Science.gov (United States)

    Farias-Moeller, R; Avery, R; Diab, Y; Carpenter, J; Murnick, J

    2016-12-01

    Variations in cerebral venous development can influence the ability to regulate drainage. In cerebral sinovenous thrombosis, these variations can be associated with elevated intracranial pressure. We present a series of pediatric patients with unilateral cerebral sinovenous thrombosis and investigate whether the contralateral venous sinus size increases the risk of developing elevated intracranial pressure. Patients diagnosed with a unilateral cerebral sinovenous thrombosis were identified by querying our institutional radiology data base. The difference in the occurrence of elevated intracranial pressure in patients with cerebral sinovenous thrombosis with and without hypoplastic venous sinuses was studied. Twelve cases of unilateral cerebral sinovenous thrombosis met the inclusion criteria and had sufficient images. Six patients had hypoplastic contralateral venous sinuses. The presence of hypoplastic contralateral venous sinus in the setting of thrombosis of a dominant sinus was associated with elevation of intracranial pressure (83% versus 0%, P = .015). Patients with cerebral sinovenous thrombosis and contralateral hypoplastic venous sinuses are at higher risk of developing elevated ICP and may benefit from screening with an ophthalmologic examination.

  5. Effect of noradrenaline on tail arteries of SHR and WKY under perfusion at constant flow and constant pressure

    DEFF Research Database (Denmark)

    Matchkov, Vladimir; Tarasova, Olga S; Timin, Eugeny N;

    1997-01-01

    pressure. Two series of experiments were performed. In the first series, vessels were perfused/superfused with Krebs-Henseleit solution. In the second one a modified salt solution was used, in which NaCl was totally replaced by an equimolar amount of KCI. Under constant flow conditions noradrenaline evoked......, vasoconstriction at constant pressure in SHR became more pronounced than that in WKY. We suggest that there is greater wall thickness:lumen diameter ratio in SHR vessels and thus different contribution of distension-activated myogenic response is of primary importance for the data obtained....... a more prominent resistance increase in SHR compared with WKY independently of the composition of solution (normal or high-K+) used. At constant pressure perfusion with normal solution, the vasoconstrictor response to noradrenaline was more prominent in WKY. Under application of high-K+ solution...

  6. Cerebral perfusion alterations in epileptic patients during peri-ictal and post-ictal phase: PASL vs DSC-MRI.

    Science.gov (United States)

    Pizzini, Francesca B; Farace, Paolo; Manganotti, Paolo; Zoccatelli, Giada; Bongiovanni, Luigi G; Golay, Xavier; Beltramello, Alberto; Osculati, Antonio; Bertini, Giuseppe; Fabene, Paolo F

    2013-07-01

    Non-invasive pulsed arterial spin labeling (PASL) MRI is a method to study brain perfusion that does not require the administration of a contrast agent, which makes it a valuable diagnostic tool as it reduces cost and side effects. The purpose of the present study was to establish the viability of PASL as an alternative to dynamic susceptibility contrast (DSC-MRI) and other perfusion imaging methods in characterizing changes in perfusion patterns caused by seizures in epileptic patients. We evaluated 19 patients with PASL. Of these, the 9 affected by high-frequency seizures were observed during the peri-ictal period (within 5hours since the last seizure), while the 10 patients affected by low-frequency seizures were observed in the post-ictal period. For comparison, 17/19 patients were also evaluated with DSC-MRI and CBF/CBV. PASL imaging showed focal vascular changes, which allowed the classification of patients in three categories: 8 patients characterized by increased perfusion, 4 patients with normal perfusion and 7 patients with decreased perfusion. PASL perfusion imaging findings were comparable to those obtained by DSC-MRI. Since PASL is a) sensitive to vascular alterations induced by epileptic seizures, b) comparable to DSC-MRI for detecting perfusion asymmetries, c) potentially capable of detecting time-related perfusion changes, it can be recommended for repeated evaluations, to identify the epileptic focus, and in follow-up and/or therapy-response assessment.

  7. 脑动脉瘤破裂手术前后的脑灌注成像探讨%The study of cerebral perfusion imaging for the ruptured cerebral aneurysms before and after the operation

    Institute of Scientific and Technical Information of China (English)

    林怡; 段玉霞; 李瑞; 陈伟建; 吴楠; 童秋云; 王殊

    2013-01-01

    目的:通过CT灌注成像观察颅内动脉瘤破裂出血手术前后的脑血流变化,为临床后续治疗提供相关信息.方法:回顾性分析颅内动脉瘤破裂手术前、后临床资料44例.所选患者术前行CT血管成像(CTA)和CT灌注成像(CTP)检查,并于术后1周行CTP复查.分别测量前后两次CTP的大脑前动脉区(ACA区)、大脑中动脉区(MCA区)、大脑后动脉区(PCA区)及基底节区灌注值.结果:44例入选患者中,34例伪彩图肉眼可见好转,患者的ACA区、MCA区、PCA区及基底节区脑血流量(CBF)与平均通过时间(MTT)变化差异有统计学意义(P< 0.05);8例肉眼可见局部灌注减低区的MTT值均延长、CBF值减低;2例灌注值未见明显异常.所有患者的脑血容量(CBV)值变化差异均无统计学意义.结论:颅内动脉瘤破裂手术前及手术后存在脑灌注调整,视个体和病情各异,脑灌注也将发生相应的变化.%Objective:To provide relevant information for clinical follow-up treatment through the observation on cerebral hemodynamic changes of ruptured intracranial aneurysm before and after operation in the CT perfusion imaging.Methods:The retrospective analysis of the pre-and post-operative clinical data in 44 patients with ruptured cerebral aneurysms was performed.These patients underwent CTA and CTP examination simultaneously before surgery,followed by CTP examination after operation.Then the perfusion values of anterior cerebral arterial territory (ACA area),middle cerebral arterial territory (MCA area),posterior cerebral arterial territory (PCA area) and basal ganglia area were respectively measured.Results:Among the 44 patients,the pseudo-color images of 34 patients showed visible improvement.In these patients,there was a significant change (P<0.05) between CBF and MTT in ACA,MCA,PCA and basal ganglia area.In the decreased perfusion area of 8 patients,which was visible to the naked eye,the MTT value was extended,and the CBF value was

  8. Cirurgia do arco aórtico com perfusão cerebral bilateral pelo isolamento do tronco braquiocefálico e da artéria carótida esquerda Aortic arch surgery with bilateral cerebral perfusion by isolation of brachiocephalic trunk and left carotid artery

    Directory of Open Access Journals (Sweden)

    Valdo José Carreira

    2008-03-01

    Full Text Available OBJETIVO: Estudar os resultados da técnica descrita por Carreira et al. com utilização de perfusão cerebral seletiva bilateral (PCSAB pelo isolamento do tronco braquiocefálico e artéria carótida esquerda. MÉTODOS: Quinze pacientes foram operados consecutivamente entre de junho de 2005 e setembro de 2007. Os dados foram analisados por programa informatizado Epi Info e significância estatística com p0,05. CONCLUSÃO: A técnica de PCSAB é reprodutível e apresenta resultados semelhantes aos da literatura mundial. A excelente evolução neurológica e o fácil controle de sangramentos nas linhas de sutura podem ter contribuído com os resultados obtidos.OBJECTIVE: To evaluate the results of a technique described by Carreira et al. using bilateral antegrade selective cerebral perfusion by isolating the brachiocephalic trunk and the left carotid artery. METHODS: Fifteen patients were operated between June 2005 and September 2007. Data analysis were performed using Epi Info and statistical significance was set at p0.05. CONCLUSION: The technique of bilateral selective cerebral perfusion described by Carreira et al. can be performed by others and presents similar results to the international literature. The excellent neurological outcome and easy bleeding control on surgical sutures lines are the major advantages of this new procedure.

  9. Estudio sobre las alteraciones de la perfusión cerebral valorado mediante SPECT cerebral, en pacientes usuarios de drogas de abuso Study of brain perfusion anomalies assessed with cerebral SPECT in drug abuse patients

    Directory of Open Access Journals (Sweden)

    Eduardo Rodríguez Raimondo

    2010-06-01

    Full Text Available El abuso de sustancias psicotóxicas representa un gran problema de Salud Pública en los diferentes distritos estatales. Este trabajo pretende determinar cuáles son los efectos nocivos de estas sustancias sobre el parénquima cerebral de los pacientes en los que se ha demostrado un consumo activo de drogas prohibidas. Para ello se empleó la técnica de SPECT cerebral con ECD - 99mTc aplicada a aquellos pacientes adictos, a los cuales previamente se les realizó una encuesta para conocer el tipo de droga, el tiempo y la duración de su adicción. Como resultado se detectó que el mayor número de defectos de perfusión corticales, es decir, déficits funcionales, se localizaron en la corteza órbito-frontal y en los lóbulos temporales, lo cual explicaría los importantes trastornos de conducta y personalidad que manifiestan estos pacientes. Se demostró con este método que el SPECT cerebral es un excelente método para detectar las zonas afectadas por estas drogas psicoadictivas, su extensión y la evolución y posible respuesta al tratamiento.Psychoactive drug abuse is a major public health problem in many districts. This study seeks to determine the harmful effects of such drugs on the brain parenchyma of patients known to abuse illegal drugs. Brain scans were obtained using 99 M Tc- ECD SPECT from drug addicts that had been previously surveyed to ascertain the type of drug, the timing and duration of their addiction SPECT findings showed a larger number of cortical perfusion defects, that is to say functional defects located in the orbital-frontal cortex and in the temporal lobes that may explain the significant behavior and personality disorders these patients display. Cerebral SPECT showed to be an excellent method to detect areas affected by psychoactive drugs, their extent, likely evolution and response to treatment.

  10. Quantitative 3D pulmonary MR-perfusion in patients with pulmonary arterial hypertension: Correlation with invasive pressure measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ley, Sebastian [Department of Pediatric Radiology, Children' s Hospital University Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg (Germany) and Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)]. E-mail: ley@gmx.net; Mereles, Derliz [Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Risse, Frank [Medical Physics in Radiology (E020), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Gruenig, Ekkehard [Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Ley-Zaporozhan, Julia [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Tecer, Zueleyha [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Puderbach, Michael [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Fink, Christian [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Department of Clinical Radiology, University Medical Center Grosshadern, Ludwigs-Maximilians-University, Munich (Germany); Kauczor, Hans-Ulrich [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)

    2007-02-15

    Purpose: Pathological changes of the peripheral pulmonary arteries induce pulmonary arterial hypertension (PAH). Aim of this study was to quantitatively assess the effect of PAH on pulmonary perfusion by 3D-MR-perfusion techniques and to compare findings to healthy controls. Furthermore, quantitative perfusion data were correlated with invasive pressure measurements. Material and methods: Five volunteers and 20 PAH patients (WHO class II or III) were examined using a 1.5 T MR scanner. Measurement of pulmonary perfusion was done in an inspiratory breathhold (FLASH3D; 3.5 mm x 1.9 mm x 4 mm; TA per 3D dataset 1.5 s). Injection of contrast media (0.1 mmol Gd-DTPA/kg BW) and image acquisition were started simultaneously. Evaluation of 3D perfusion was done using singular value decomposition. Lung borders were outlined manually. Each lung volume was divided into three regions (anterior, middle, posterior), and the following parameters were assessed: Time-to-Peak (TTP), blood flow (PBF), blood volume (PBV), and mean transit time (MTT). In 10 patients invasive pulmonary artery pressure measurements were available and correlated to the perfusion measurements. Results: In both, controls and patients, an anterior-to-posterior gradient with higher PBF and PBV posterior was observed. In the posterior lung region, a significant difference (p < 0.05) was found for TTP (12 s versus 16 s) and MTT (4 s versus 6 s) between volunteers and patients. PBF and PBV were lower in patients than in volunteers (i.e. dorsal regions: 124 versus 180 ml/100 ml/min and 10 versus 12 ml/100 ml), but the difference failed to be significant. The ratio of PBF and PBV between the posterior and the middle or ventral regions showed no difference between both groups. A moderate linear correlation between mean pulmonary arterial pressure (mPAP) and PBV (r = 0.51) and MTT (r = 0.56) was found. Conclusion: The only measurable effect of PAH on pulmonary perfusion is a prolonging of the MTT. There is only a

  11. Effectiveness of skin perfusion pressure monitoring during surgery for an ischemic steal syndrome associated refractory ulcer.

    Science.gov (United States)

    Okubo, Kentaro; Sato, Takashi; Matsubara, Chieko; Tsuboi, Masato; Ishii, Yasuo; Tojimbara, Tamotsu

    2015-01-01

    We describe an 80-year-old man with end-stage renal disease due to type 2 diabetes who had been maintained on hemodialysis for 9 years. He developed refractory ulcers from an abraded wound in the right hand of his access arm. The arteriovenous fistula (AVF) was located between the right brachial artery and the median antecubital vein draining into the cephalic vein and the deep veins close to the elbow. The blood flow of the right brachial artery measured by using Doppler ultrasonography was 920 ml/min. On the contrary, the radial and ulnar arteries were poorly palpable near the wrist, and ultrasonography could not be performed accurately because of a high degree of calcification. The skin perfusion pressure (SPP) of the first finger on the affected side decreased to 22 mmHg. However, the SPP improved to approximately 40 mmHg upon blocking an inflow into the deep vein. According to SPP data, only a communicating branch of the deep vein was ligated, and the AVF itself was preserved. One month after surgery, the skin ulcer healed, and maintenance hemodialysis was performed by using the preserved cephalic vein for blood access.In conclusion, we successfully treated a refractory wound associated with steal syndrome, without terminating the AVF. SPP-guided surgery may be safe and effective to adjust the blood flow in patients with AVF having steal syndrome.

  12. Gradual Rewarming with Gradual Increase in Pressure during Machine Perfusion after Cold Static Preservation Reduces Kidney Ischemia Reperfusion Injury.

    Directory of Open Access Journals (Sweden)

    Paria Mahboub

    Full Text Available In this study we evaluated whether gradual rewarming after the period of cold ischemia would improve organ quality in an Isolated Perfused Kidney Model. Left rat kidneys were statically cold stored in University of Wisconsin solution for 24 hours at 4°C. After cold storage kidneys were rewarmed in one of three ways: perfusion at body temperature (38°C, or rewarmed gradually from 10°C to 38°C with stabilization at 10°C for 30 min and rewarmed gradually from 10°C to 38°C with stabilization at 25°C for 30 min. In the gradual rewarming groups the pressure was increased stepwise to 40 mmHg at 10°C and 70 mmHg at 25°C to counteract for vasodilatation leading to low perfusate flows. Renal function parameters and injury biomarkers were measured in perfusate and urine samples. Increases in injury biomarkers such as aspartate transaminase and lactate dehydrogenase in the perfusate were lower in the gradual rewarming groups versus the control group. Sodium re-absorption was improved in the gradual rewarming groups and reached significance in the 25°C group after ninety minutes of perfusion. HSP-70, ICAM-1, VCAM-1 mRNA expressions were decreased in the 10°C and 25°C groups. Based on the data kidneys that underwent gradual rewarming suffered less renal parenchymal, tubular injury and showed better endothelial preservation. Renal function improved in the gradual rewarming groups versus the control group.

  13. Comparison of CT perfusion summary maps to early diffusion-weighted images in suspected acute middle cerebral artery stroke

    Energy Technology Data Exchange (ETDEWEB)

    Benson, John; Payabvash, Seyedmehdi [Hennepin County and University of Minnesota Medical Centers, Department of Radiology, Minneapolis, MN (United States); Salazar, Pascal [Vital Images, A Division of Toshiba Medical, Minnetonka, MN (United States); Jagadeesan, Bharathi; Palmer, Christopher S.; Truwit, Charles L. [Hennepin County and University of Minnesota Medical Centers, Department of Radiology, Minneapolis, MN (United States); McKinney, Alexander M., E-mail: mckinrad@umn.edu [Hennepin County and University of Minnesota Medical Centers, Department of Radiology, Minneapolis, MN (United States)

    2015-04-15

    Objectives: To assess the accuracy and reliability of one vendor's (Vital Images, Toshiba Medical, Minnetonka, MN) automated CT perfusion (CTP) summary maps in identification and volume estimation of infarcted tissue in patients with acute middle cerebral artery (MCA) distribution infarcts. Subjects and methods: From 1085 CTP examinations over 5.5 years, 43 diffusion-weighted imaging (DWI)-positive patients were included who underwent both CTP and DWI <12 h after symptom onset, with another 43 age-matched patients as controls (DWI-negative). Automated delay-corrected postprocessing software (DC-SVD) generated both infarct “core only” and “core + penumbra” CTP summary maps. Three reviewers independently tabulated Alberta Stroke Program Early CT scores (ASPECTS) of both CTP summary maps and coregistered DWI. Results: Of 86 included patients, 36 had DWI infarct volumes ≤70 ml, 7 had volumes >70 ml, and 43 were negative; the automated CTP “core only” map correctly classified each as >70 ml or ≤70 ml, while the “core + penumbra” map misclassified 4 as >70 ml. There were strong correlations between DWI volume with both summary map-based volumes: “core only” (r = 0.93), and “core + penumbra” (r = 0.77) (both p < 0.0001). Agreement between ASPECTS scores of infarct core on DWI with summary maps was 0.65–0.74 for “core only” map, and 0.61–0.65 for “core + penumbra” (both p < 0.0001). Using DWI-based ASPECTS scores as the standard, the accuracy of the CTP-based maps were 79.1–86.0% for the “core only” map, and 83.7–88.4% for “core + penumbra.” Conclusion: Automated CTP summary maps appear to be relatively accurate in both the detection of acute MCA distribution infarcts, and the discrimination of volumes using a 70 ml threshold.

  14. Antiphospholipid Antibody Syndrome: Raised Intracranial Pressure Without Cerebral Venous Sinus Thrombosis.

    Science.gov (United States)

    Rudich, Danielle S; Yun, Samuel H; Liebling, Anne; Silbert, Jonathan E; Moeckel, Gilbert W; Lesser, Robert L

    2015-12-01

    Antiphospholipid antibody syndrome (APS) has been reported to cause elevated intracranial pressure, but usually this is due to cerebral venous sinus thrombosis (CVST). We present a 36-year old man with APS with elevated intracranial pressure with neuro-ophthalmic, renal and hematological involvement without identifiable CVST.

  15. Volume perfusion CT (VPCT) for the differential diagnosis of patients with suspected cerebral vasospasm: Qualitative and quantitative analysis of 3D parameter maps

    Energy Technology Data Exchange (ETDEWEB)

    Dolatowski, K., E-mail: karoline.dolatowski@gmail.com [Department of Neuroradiology, University Medicine Göttingen, Robert-Koch-Str. 40, 37075 Göttingen (Germany); Malinova, V., E-mail: vesna.malinova@gmail.com [Department of Neurosurgery, University Medicine Göttingen, Robert-Koch-Str. 40, 37075 Göttingen (Germany); Frölich, A.M.J., E-mail: a.froelich@gmail.com [Department of Neuroradiology, University Medicine Göttingen, Robert-Koch-Str. 40, 37075 Göttingen (Germany); Schramm, R., E-mail: ramona.schramm@med.uni-goettingen.de [Department of Neuroradiology, University Medicine Göttingen, Robert-Koch-Str. 40, 37075 Göttingen (Germany); Haberland, U., E-mail: ulrike.haberland@siemens.com [Siemens AG, Healthcare Sector, Computed Tomography, H IM CR R and D PA SC, Siemensstr. 1, 91301 Forchheim (Germany); Klotz, E., E-mail: ernst.klotz@siemens.com [Siemens AG, Healthcare Sector, Computed Tomography, H IM CR R and D PA SC, Siemensstr. 1, 91301 Forchheim (Germany); Mielke, D., E-mail: dorothee.wachter@med.uni-goettingen.de [Department of Neurosurgery, University Medicine Göttingen, Robert-Koch-Str. 40, 37075 Göttingen (Germany); Knauth, M., E-mail: michael.knauth@med.uni-goettingen.de [Department of Neuroradiology, University Medicine Göttingen, Robert-Koch-Str. 40, 37075 Göttingen (Germany); Schramm, P., E-mail: Peter.Schramm@uksh.de [Department of Neuroradiology, UKSH University hospital Schleswig-Holstein Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck (Germany)

    2014-10-15

    Object: Cerebral vasospasm (CV) following subarachnoid hemorrhage (SAH) implies high risk for secondary ischemia. It requires early diagnosis to start treatment on time. We aimed to assess the utility of “whole brain” VPCT for detecting localization and characteristics of arterial vasospasm. Methods: 23 patients received a non-enhanced CT, VPCT and CTA of the brain. The distribution of ischemic lesions was analyzed on 3D-perfusion-parameter-maps of CBF, CBV, MTT, TTS, TTP, and TTD. CT-angiographic axial and coronal maximum-intensity-projections were reconstructed to determine arterial vasospasm. CT-data was compared to DSA, if performed additionally. Volume-of-interest placement was used to obtain quantitative mean VPCT values. Results: 82% patients (n = 19) had focal cerebral hypoperfusion. 100% sensitivity and 100% specificity was found for TTS (median 1.9 s), MTT (median 5.9 s) and TTD (median 7.6 s). CBV showed no significant differences. In 78% (n = 18) focal vessel aberrations could be detected either on CTA or DSA or on both. Conclusion: VPCT is a non-invasive method with the ability to detect focal perfusion deficits almost in the whole brain. While DSA remains to be the gold standard for detection of CV, VPCT has the potential to improve noninvasive diagnosis and treatment decisions.

  16. Surfactant nebulisation prevents the adverse effects of surfactant therapy on blood pressure and cerebral blood flow in rabbits with severe respiratory failure

    NARCIS (Netherlands)

    Dijk, PH; Heikamp, A; Oetomo, SB

    1997-01-01

    Objective: Surfactant replacement therapy for the neonatal respiratory distress syndrome has shown beneficial effects on lung function and survival. Recently, rapid fluctuations of haemodynamics and cerebral perfusion following surfactant instillation have beer, described and an association with the

  17. Analysis of dynamic cerebral contrast-enhanced perfusion MRI time-series based on unsupervised clustering methods

    Science.gov (United States)

    Lange, Oliver; Meyer-Baese, Anke; Wismuller, Axel; Hurdal, Monica

    2005-03-01

    We employ unsupervised clustering techniques for the analysis of dynamic contrast-enhanced perfusion MRI time-series in patients with and without stroke. "Neural gas" network, fuzzy clustering based on deterministic annealing, self-organizing maps, and fuzzy c-means clustering enable self-organized data-driven segmentation w.r.t.fine-grained differences of signal amplitude and dynamics, thus identifying asymmetries and local abnormalities of brain perfusion. We conclude that clustering is a useful extension to conventional perfusion parameter maps.

  18. Spatial frequency-based analysis of mean red blood cell speed in single microvessels: investigation of microvascular perfusion in rat cerebral cortex.

    Directory of Open Access Journals (Sweden)

    Joonas Autio

    Full Text Available BACKGROUND: Our previous study has shown that prenatal exposure to X-ray irradiation causes cerebral hypo-perfusion during the postnatal development of central nervous system (CNS. However, the source of the hypo-perfusion and its impact on the CNS development remains unclear. The present study developed an automatic analysis method to determine the mean red blood cell (RBC speed through single microvessels imaged with two-photon microscopy in the cerebral cortex of rats prenatally exposed to X-ray irradiation (1.5 Gy. METHODOLOGY/PRINCIPAL FINDINGS: We obtained a mean RBC speed (0.9±0.6 mm/sec that ranged from 0.2 to 4.4 mm/sec from 121 vessels in the radiation-exposed rats, which was about 40% lower than that of normal rats that were not exposed. These results were then compared with the conventional method for monitoring microvascular perfusion using the arteriovenous transit time (AVTT determined by tracking fluorescent markers. A significant increase in the AVTT was observed in the exposed rats (1.9±0.6 sec as compared to the age-matched non-exposed rats (1.2±0.3 sec. The results indicate that parenchyma capillary blood velocity in the exposed rats was approximately 37% lower than in non-exposed rats. CONCLUSIONS/SIGNIFICANCE: The algorithm presented is simple and robust relative to monitoring individual RBC speeds, which is superior in terms of noise tolerance and computation time. The demonstrative results show that the method developed in this study for determining the mean RBC speed in the spatial frequency domain was consistent with the conventional transit time method.

  19. Optical clearing agent perfusion enhancement via combination of microneedle poration, heating and pneumatic pressure

    OpenAIRE

    Damestani, Y; Melakeberhan, B; Rao, MP; Aguilar, G.

    2014-01-01

    Background and Objective Optical clearing agents (OCAs) have shown promise for increasing the penetration depth of biomedical lasers by temporarily decreasing optical scattering within the skin. However, their translation to the clinic has been constrained by lack of practical means for effectively perfusing OCA within target tissues in vivo. The objective of this study was to address this limitation through combination of a variety of techniques to enhance OCA perfusion, including heating of...

  20. Comparison of the cerebral SPECT and biological markers in the Alzheimer disease; Comparaison de la tomographie cerebrale par emission monophotonique de perfusion et des biomarqueurs dans la maladie d'Alzheimer

    Energy Technology Data Exchange (ETDEWEB)

    Ravasi, L.; Semah, F.; Steinling, M. [Unite imagerie fonctionnelle cerebrale, CHRU de Lille, (France); Bombois, S.; Pasquier, F. [centre memoire de ressources et de recherche, CHRU de Lille, (France); Schraen, S.; Buee, L. [Inserm U837, centre de biologie, CHRU de Lille, (France)

    2009-05-15

    This study aim was to compare the contribution of SPECT of cerebral perfusion and bio markers of the cerebrospinal liquid in the diagnosis of Alzheimer disease. Our preliminary conclusions show that the concordance of the SPECT and cerebrospinal liquid is good in the possible Alzheimer disease. the interest of the cerebral SPECT and bio markers of the cerebrospinal liquid, used alone or conjointly, for a more reliable diagnosis of Alzheimer disease must be evaluated of prospective way. (N.C.)

  1. Closed-loop control of renal perfusion pressure in physiological experiments.

    Science.gov (United States)

    Campos-Delgado, D U; Bonilla, I; Rodríguez-Martínez, M; Sánchez-Briones, M E; Ruiz-Hernández, E

    2013-07-01

    This paper presents the design, experimental modeling, and control of a pump-driven renal perfusion pressure (RPP)-regulatory system to implement precise and relatively fast RPP regulation in rats. The mechatronic system is a simple, low-cost, and reliable device to automate the RPP regulation process based on flow-mediated occlusion. Hence, the regulated signal is the RPP measured in the left femoral artery of the rat, and the manipulated variable is the voltage applied to a dc motor that controls the occlusion of the aorta. The control system is implemented in a PC through the LabView software, and a data acquisition board NI USB-6210. A simple first-order linear system is proposed to approximate the dynamics in the experiment. The parameters of the model are chosen to minimize the error between the predicted and experimental output averaged from eight input/output datasets at different RPP operating conditions. A closed-loop servocontrol system based on a pole-placement PD controller plus dead-zone compensation was proposed for this purpose. First, the feedback structure was validated in simulation by considering parameter uncertainty, and constant and time-varying references. Several experimental tests were also conducted to validate in real time the closed-loop performance for stepwise and fast switching references, and the results show the effectiveness of the proposed automatic system to regulate the RPP in the rat, in a precise, accurate (mean error less than 2 mmHg) and relatively fast mode (10-15 s of response time).

  2. Three-dimensional perfusion imaging in acute cerebral infarction%三维CT灌注成像在急性脑梗死中的应用

    Institute of Scientific and Technical Information of China (English)

    戴峰; 高歌军; 文颂; 颜利辉

    2009-01-01

    目的 探讨将三维CT脑灌注加权成像(PWM)和脑灌注血容量成像(PBV)整合优化到急性缺血性脑梗死脑CT灌注成像(CTP)联合脑CT血管成像(CTA)扫描方案中的价值.方法 对23例临床诊断急性脑梗死患者行CTP联合CTA检查,将增强CTA原始数据或增强CTA与平扫CTA减影的原始数据通过图像工作站处理,得到脑三维CT PWM和三维CT全脑PBV的伪彩图像,评价CTP与PWM、PBV在诊断急性脑梗死上的敏感性和整合运用的意义. 结果 23例临床诊断急性脑梗死患者,9例单纯CTP图像显示阴性患者中有7例在PWM、PBV图像上有阳性改变;单纯CTP观测急性脑梗死的敏感性约60.87%,CTP与PWM、PBV整合观测急性脑梗死的敏感性约91.30%. 结论 将三维CT脑PWM和脑PBV整合优化到急性脑梗死CT检查方案中,不仅能提高急性脑梗死的检出率,而且能预测患者预后.%Objective To assess the value of whole cerebral perfusion weighted map (PWM) and whole cerebral perfusion blood volume (PBV) integrating in scan protocol about CT perfusion (CTP) combined with CT angiography (CTA) in acute cerebral infarction. Methods Twenty-three patients with acute cerebral infarction proved clinically underwent CTP examination combined with CTA. The color-coded images of PWM and PBV were attained using workstation, and the raw data of contract CTA images and subtractive images between contract CTA and non-contract CTA were processed. The diagnostic sensitivity and the value of CTP and PWM, PBV integrating CTP in acute cerebral infraction were evaluated. Results Seven of 9 patients with negative results on CTP images had positive expressions on PWM and PBV images. The sensitivity of CTP was 60.87% and the sensitivity of PWM and PBV integrating CTP was 91.30%. Conclusion The scan protocol of PWM, PBV integrating CTP not only increases detection rate of acute cerebral infraction, but also has ability to predict the clinical prognosis of patients with cerebral

  3. Increased perfusion pressure enhances the expression of endothelin (ETB) and angiotensin II (AT1, AT2) receptors in rat mesenteric artery smooth muscle cells

    DEFF Research Database (Denmark)

    Lindstedt, Isak; Xu, Cang-Bao; Zhang, Yaping;

    2009-01-01

    and luminally perfused in a perfusion chamber. After either exposure to no ("organ culture" (0 mmHg)), normal (85/75 mmHg) or high pressure (160/150 mmHg) at constant flow for 1-17 h, the vessel segments were snap frozen and real-time polymerase chain reaction was performed to quantify the ET- and AT-receptor m......RNA content, or immersed in a fixative solution, dehydrated, frozen, cut in a cryostat and immunohistology stained for ET- and AT-receptor protein. The mRNA expressions of ETB and of AT2 were significantly enhanced in vessels exposed to high perfusion pressure, compared with normal and no perfusion pressure...

  4. Human cerebral venous outflow pathway depends on posture and central venous pressure

    DEFF Research Database (Denmark)

    Gisolf, J; van Lieshout, J J; van Heusden, K;

    2004-01-01

    , but mainly through the vertebral plexus in the upright position. A Valsalva manoeuvre while standing completely re-opened the jugular veins. Results of ultrasound imaging of the right internal jugular vein cross-sectional area at the level of the laryngeal prominence in six healthy subjects, before......Internal jugular veins are the major cerebral venous outflow pathway in supine humans. In upright humans the positioning of these veins above heart level causes them to collapse. An alternative cerebral outflow pathway is the vertebral venous plexus. We set out to determine the effect of posture...... and central venous pressure (CVP) on the distribution of cerebral outflow over the internal jugular veins and the vertebral plexus, using a mathematical model. Input to the model was a data set of beat-to-beat cerebral blood flow velocity and CVP measurements in 10 healthy subjects, during baseline rest...

  5. 慢性大脑中动脉狭窄或闭塞的CT灌注成像%CT perfusion imaging in patients with chronic middle cerebral artery stenosis or occlusion

    Institute of Scientific and Technical Information of China (English)

    苏凯燕; 刘增韬

    2012-01-01

    Objective To evaluate the blood perfusion character of chronic middle cerebral artery stenosis or occlusion with CT perfusion imaging. Methods The clinical and imaging dala of 11 cases with unilateral chronic middle cerebral artery stenosis or occlusion were collected. All cases were examined with CT perfusion and MR (MR1 and MKA). Results The CT perfusion character of chronic middle cerebral artery stenosis or occlusion included CBV elevated, CBF decreased, and MTI prolonged. Conclusion CT perfusion imaging can describe the blood perfusion character of chronic middle cerebral artery stenosis or occlusion, and provide theoretical basis for therapeutic plan.%目的 利用CT灌注成像技术研究慢性大动脉狭窄或闭塞患者的脑血流灌注特征.方法 搜集具有完整临床资料的单侧慢性大脑中动脉重度狭窄或闭寨患者11例,行CT灌注成像及磁共振(MRI及MRA)检查.结果 慢性大脑中动脉狭窄或闭塞患者的脑CT灌注特征是患侧脑血流量(CBF)降低,脑血容量(CBV)升高,平均通过时间(MTT)延长.结论 CT灌注成像能反映慢性大脑中动脉狭窄或闭塞患者的脑血流灌注特征,为临床治疗方案的制订提供理论依据.

  6. [Influence of 2-ethyl-6-methyl-3-hydroxypyridine hemisuccinate on cerebral blood perfusion in rats under experimental pathology conditions].

    Science.gov (United States)

    Gan'shina, T S; Gorbunov, A A; Gnezdilova, A V; Kurdiumov, I N; Avdiunina, N I; Piatin, B M; Mirzoian, R S

    2011-01-01

    Experiments on rats showed that 2-ethyl-6-methyl-3-hydroxypyridine hemisuccinate increases cerebral blood flow in the system of carotid arteries both in intact animals and under conditions of global transient ischemia. In combination with tropoxin, 2-ethyl-6-methyl-3-hydroxypyridine hemisuccinate enhances the blood flow in the inner carotid artery of intact rats and the local blood flow under conditions of global transient ischemia. A combination of 2-ethyl-6-methyl-3-hydroxypyridine hemisuccinate and tropoxin increases baseline cerebral blood flow and decreases the constrictor reaction of cerebral blood vessels to 5HT(2B/2C) receptor agonist meta-chlorophenylpiperazine.

  7. Pulsatile ex vivo perfusion of human saphenous vein grafts under controlled pressure conditions increases MMP-2 expression

    Directory of Open Access Journals (Sweden)

    Lange Rüdiger

    2011-07-01

    Full Text Available Abstract Background The use of human saphenous vein grafts (HSVGs as a bypass conduit is a standard procedure in the treatment of coronary artery disease while their early occlusion remains a major problem. Methods We have developed an ex vivo perfusion system, which uses standardized and strictly controlled hemodynamic parameters for the pulsatile and non-static perfusion of HSVGs to guarantee a reliable analysis of molecular parameters under different pressure conditions. Cell viability of HSVGs (n = 12 was determined by the metabolic conversion of 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl-tetrazolium bromide (MTT into a purple formazan dye. Results Under physiological flow rates (10 mmHg HSVGs remained viable for two weeks. Their exposure to arterial conditions (100 mmHg was possible for one week without important reduction in viability. Baseline expression of matrix metalloproteinase-2 (MMP-2 after venous perfusion (2.2 ± 0.5, n = 5 was strongly up-regulated after exposure to arterial conditions for three days (19.8 ± 4.3 or five days (23.9 ± 6.1, p Conclusion Therefore, our system might be helpful to more precisely understand the molecular mechanisms leading to an early failure of HSVGs.

  8. The Effects of Nifedipine on Renal Perfusion Pressure and Kidney During Cisplatin-Induced Nephrotoxicity in Rats

    Directory of Open Access Journals (Sweden)

    Meral Erdinç

    2007-01-01

    Full Text Available Cisplatin is one of the most effective cancer chemotherapeutic agent used against various solid tumors. Nephrotoxicity is one of the major dose-limiting side effects of cisplatin. It has been known that different mechanisms as oxidative stress may play an important role in cisplatin induced nephrotoxicity resulted with changes in renal haemodynamics. This study was performed to investigate the effect of nifedipine –one of the dihydropyridine calcium antagonist on changes in renal perfusion pressures and kidneys of rats with cisplatin nephrotoxicity. Male wistar albino rats were divided into 3 groups (n=8:1-Control group(1 ml saline. i.p 2-Cisplatin group (a single dose of cisplatin (5 mg/kg, i.p 3- A single dose of cisplatin (5 mg/kg, i.p + Nifedipine (2 mg/kg/day, i.p for five days. When those pre-treated groups compared with control group, perfusion pressures, serum urea and creatinine levels and tissue MDA levels were found significantly higher in cisplatin group (p<0.001. Histopathological examination showed widespread tubular necrosis and dilatation in cisplatin-treated group versus other groups. In cisplatin + nifedipine pretreated group, perfusion pressures, serum urea and creatinine levels and tissue MDA levels found significantly lower than cisplatin group (p<0. 001 and less tubular dilatation and necrosis was observed. As a result it was demonstrated that Nifedipine has protective effects against cisplatin nephrotoxicity. We suggest that this is partly provided by the beneficial effects of nifedipine on altered renal haemodynamics during cisplatin nephrotoxicity.

  9. Acute retinal ischemia caused by controlled low ocular perfusion pressure in a porcine model. Electrophysiological and histological characterisation

    DEFF Research Database (Denmark)

    Kyhn, Maria Voss; Warfvinge, Karin; Scherfig, Erik;

    2009-01-01

    The purpose of this study was to establish, and characterize a porcine model of acute, controlled retinal ischemia. The controlled retinal ischemia was produced by clamping the ocular perfusion pressure (OPP) in the left eye to 5 mm Hg for 2 h. The OPP was defined as mean arterial blood pressure...... (MAP) minus the intraocular pressure (IOP). It was clamped to 0-30 mm Hg by continuous monitoring of MAP and adjustment of the IOP, which was controlled by cannulation of the anterior chamber. Inner retinal function was assessed by induced multifocal electroretinography (mfERG) with comparisons...... of the amplitudes obtained in the experimental, left eye, and the control, right eye. Quantitative histology was performed to measure the survival of ganglion cells, amacrine cells and horizontal cells 2-6 weeks after the ischemic insult. An OPP of 5 mm Hg for 2h induced significant reductions in the amplitudes...

  10. Heat-washout measurements compared to distal blood pressure and perfusion in orthopaedic patients with foot ulcers

    DEFF Research Database (Denmark)

    Midttun, M; Azad, B B S; Broholm, R

    2015-01-01

    Distal blood pressure and local skin perfusion pressure were compared to measurement of blood flow rate (BFR) measured by the heat-washout method in orthopaedic patients with and without diabetes, all with a foot ulcer in one foot, compared to healthy controls. The correlation was good between heat......-washout and distal blood pressure in patients with diabetes with and without an ulcer (P = 0·024 and 0·059, respectively). The correlation was weak in patients without diabetes with and without an ulcer, most probably due to power problems (P = 0·118 and 0·116, respectively). The correlation in the healthy controls...... the surrounding tissue, and therefore, measurements are easier made in these subjects. BFR in the first toe increased significantly in all patients when the foot was moved from heart level to 50 cm below heart level (P = between 0·03 and 0·05) as previously seen in patients with claudication...

  11. Perfusion MRI derived indices of microvascular shunting and flow control correlate with tumor grade and outcome in patients with cerebral glioma

    DEFF Research Database (Denmark)

    Tietze, Anna; Mouridsen, Kim; Lassen-Ramshad, Yasmin

    2015-01-01

    of microvascular flow control and the extent to which oxygen can be extracted by tumor tissue. The ability of these parameters and CBV to differentiate tumor grade were assessed by receiver operating characteristic curves and logistic regression. Their ability to predict time to progression and overall survival......Objectives: Deficient microvascular blood flow control is thought to cause tumor hypoxia and increase resistance to therapy. In glioma patients, we tested whether perfusion-weighted MRI (PWI) based indices of microvascular flow control provide more information on tumor grade and patient outcome...... than does the established PWI angiogenesis marker, cerebral blood volume (CBV). Material and Methods: Seventy-two glioma patients (sixty high-grade, twelve low-grade gliomas) were included. Capillary transit time heterogeneity (CTH) and COV, its ratio to blood mean transit time, provide indices...

  12. Association of brain amyloid-β with cerebral perfusion and structure in Alzheimer's disease and mild cognitive impairment.

    Science.gov (United States)

    Mattsson, Niklas; Tosun, Duygu; Insel, Philip S; Simonson, Alix; Jack, Clifford R; Beckett, Laurel A; Donohue, Michael; Jagust, William; Schuff, Norbert; Weiner, Michael W

    2014-05-01

    Patients with Alzheimer's disease have reduced cerebral blood flow measured by arterial spin labelling magnetic resonance imaging, but it is unclear how this is related to amyloid-β pathology. Using 182 subjects from the Alzheimer's Disease Neuroimaging Initiative we tested associations of amyloid-β with regional cerebral blood flow in healthy controls (n = 51), early (n = 66) and late (n = 41) mild cognitive impairment, and Alzheimer's disease with dementia (n = 24). Based on the theory that Alzheimer's disease starts with amyloid-β accumulation and progresses with symptoms and secondary pathologies in different trajectories, we tested if cerebral blood flow differed between amyloid-β-negative controls and -positive subjects in different diagnostic groups, and if amyloid-β had different associations with cerebral blood flow and grey matter volume. Global amyloid-β load was measured by florbetapir positron emission tomography, and regional blood flow and volume were measured in eight a priori defined regions of interest. Cerebral blood flow was reduced in patients with dementia in most brain regions. Higher amyloid-β load was related to lower cerebral blood flow in several regions, independent of diagnostic group. When comparing amyloid-β-positive subjects with -negative controls, we found reductions of cerebral blood flow in several diagnostic groups, including in precuneus, entorhinal cortex and hippocampus (dementia), inferior parietal cortex (late mild cognitive impairment and dementia), and inferior temporal cortex (early and late mild cognitive impairment and dementia). The associations of amyloid-β with cerebral blood flow and volume differed across the disease spectrum, with high amyloid-β being associated with greater cerebral blood flow reduction in controls and greater volume reduction in late mild cognitive impairment and dementia. In addition to disease stage, amyloid-β pathology affects cerebral blood flow across the span from controls to

  13. Pulsatile Intracranial Pressure and Cerebral Autoregulation After Traumatic Brain Injury

    NARCIS (Netherlands)

    Radolovich, D. K.; Aries, M.J.H.; Castellani, G.; Corona, A.; Lavinio, A.; Smielewski, P.; Pickard, J. D.; Czosnyka, M.

    2011-01-01

    Strong correlation between mean intracranial pressure (ICP) and its pulse wave amplitude (AMP) has been demonstrated in different clinical scenarios. We investigated the relationship between invasive mean arterial blood pressure (ABP) and AMP to explore its potential role as a descriptor of cerebrov

  14. Timing-invariant reconstruction for deriving high-quality CT angiographic data from cerebral CT perfusion data.

    NARCIS (Netherlands)

    Smit, E.J.; Vonken, E.J.; Schaaf, I.C. van der; Mendrik, A.M.; Dankbaar, J.W.; Horsch, A.D.; Seeters, T. van; Ginneken, B. van; Prokop, M.

    2012-01-01

    PURPOSE: To suggest a simple and robust technique used to reconstruct high-quality computed tomographic (CT) angiographic images from CT perfusion data and to compare it with currently used CT angiography techniques. MATERIALS AND METHODS: Institutional review board approval was waived for this retr

  15. Assessment of local changes of cerebral perfusion and blood concentration by ultrasound harmonic B-mode contrast measurement in piglet.

    NARCIS (Netherlands)

    Wijk, M.C. van; Klaessens, J.H.G.M.; Hopman, J.C.W.; Liem, K.D.; Thijssen, J.M.

    2003-01-01

    This study tested the hypothesis that changes in the blood concentration, and possibly in the perfusion, of different areas in the brain can be assessed by the use of ultrasound contrast agent (CA) and (linear) echo densitometry. The experiments were performed with piglets (n=3) under general anesth

  16. Automated versus manual post-processing of perfusion-CT data in patients with acute cerebral ischemia: influence on interobserver variability

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Bruno P.; Bhogal, Sumail; Dillon, William P.; Wintermark, Max [University of California, Department of Radiology, Neuroradiology Section, 505 Parnassus Avenue, Box 0628, San Francisco, CA (United States); Dankbaar, Jan Willem [University of California, Department of Radiology, Neuroradiology Section, 505 Parnassus Avenue, Box 0628, San Francisco, CA (United States); University Medical Center, Department of Radiology, Utrecht (Netherlands); Bredno, Joerg [Philips Research North America, San Francisco, CA (United States); Cheng, SuChun [University of California, Department of Epidemiology and Biostatistics, San Francisco, CA (United States)

    2009-07-15

    The purpose of this study is to compare the variability of PCT results obtained by automatic selection of the arterial input function (AIF), venous output function (VOF) and symmetry axis versus manual selection. Imaging data from 30 PCT studies obtained as part of standard clinical stroke care at our institution in patients with suspected acute hemispheric ischemic stroke were retrospectively reviewed. Two observers performed the post-processing of 30 CTP datasets. Each observer processed the data twice, the first time employing manual selection of AIF, VOF and symmetry axis, and a second time using automated selection of these same parameters, with the user being allowed to adjust them whenever deemed appropriate. The volumes of infarct core and of total perfusion defect were recorded. The cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT) and blood-brain barrier permeability (BBBP) values in standardized regions of interest were recorded. Interobserver variability was quantified using the Bland and Altman's approach. Automated post-processing yielded lower coefficients of variation for the volume of the infarct core and the volume of the total perfusion defect (15.7% and 5.8%, respectively) compared to manual post-processing (31.0% and 12.2%, respectively). Automated post-processing yielded lower coefficients of variation for PCT values (11.3% for CBV, 9.7% for CBF, and 9.5% for MTT) compared to manual post-processing (23.7% for CBV, 32.8% for CBF, and 16.7% for MTT). Automated post-processing of PCT data improves interobserver agreement in measurements of CBV, CBF and MTT, as well as volume of infarct core and penumbra. (orig.)

  17. Epileptic patterns of local cerebral metabolism and perfusion in man determined by emission computed tomography of /sup 18/FDG and /sup 13/NH/sub 3/

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, D.E.; Engel, J. Jr.; Phelps, M.E.; Selin, C.

    1979-01-01

    Seventeen patients with partial epilepsy had EEG monitoring concurrent with cerebral emission computed tomography (ECT) after /sup 18/F-fluorodeoxyglucose (/sup 18/FDG) and /sup 13/N-ammonia were given intravenously as indicators of local cerebral glucose utilization (LCMR/sub glc/) and relative perfusion, respectively. In 12 of 15 patients who had unilateral or focal electrical abnormalities, interictal /sup 18/FDG scan patterns clearly showed localized regions of decreased (20% to 50%) LCMR/sub glc/, which correlated anatomically with the eventual EEG localization. These hypometabolic zones appeared normal on x-ray computed tomography in all but three patients and were unchanged on scans repeated on different days. In 5 of 6 patients who underwent temporal lobectomy, the interictal /sup 18/FDG scan correctly detected the pathologically confirmed lesion as a hypometabolic zone, and removal of the lesion site resulted in marked clinical improvement. In contrast, the ictal /sup 18/FDG scan patterns clearly showed foci of increased (82% to 130%) LCMR/sub glc/, which correlated temporally and anatomically with ictal EEG spike foci and were within the zones of interictal hypometabolism (3 studies in 2 patients). /sup 13/NH/sub 3/ distributions paralleled /sup 18/FDG increases and decreases in abnormal zones, but /sup 13/NH/sub 3/ differences were of lesser magnitude. When the relationship of /sup 13/NH/sub 3/ uptake to local blood flow found in dog brain was applied as a correction to the patients' /sup 13/NH/sub 3/ scan data, local alterations in perfusion and glucose utilization were usually matched, both in the interictal and ictal states.

  18. Therapeutic Effects of Tongxinluo Capsule(通心络胶囊) on Patients with Acute Small Cerebral Infarction and Its Influence on SPECT Brain Perfusion Image

    Institute of Scientific and Technical Information of China (English)

    周盛年; 周国钰; 刘黎青

    2004-01-01

    Objective: To investigate the influence of Tongxinluo capsule (TXL, 通心络胶囊) on regional cerebral blood flow (rCBF) with 99mTc-ECD single photon emission computed tomography ( SPECT) brain perfusion imaging, and to observe the therapeutic effects of TXL on acute small cerebral infarction (ASCI).Methods: Thirty-four patients with ASCI were enrolled and randomly divided into two groups: the control group ( n = 17) was treated with the conventional treatment, i.e. 1.0g of Citicoline added into 300 mi normal saline for intravenous dripping daily for 2 weeks and 0.8 g of Piracetam taken three times a day orally for 4 weeks, and the treatment group ( n = 17)was treated additionally with 4 TXL capsules three times a day for 4 weeks besides the conventional treatment. The 99mTc-ECD SPECT brain perfusion imaging was performed before and after treatment to observe the change of rCBF, and the neurological deficit was evaluated by Edinburgh-Scandinavia stroke scale (SSS) scores and Barthel index (BI) at the same time. Results: After treatment, the rCBF in the treatment group was significantly improved ( P<0.01), while that in the control group remained unchanged, with the comparison of the rCBF in the two groups after treatment showing significant difference (P<0.01). In addition, the SSS score was significantly lower and BI significantly higher in the treatment group than those in the control group respectively after treatment. Conclusion: TXL could effectively improve rCBF and lessen the neurological deficit symptoms in patients with ASCI.

  19. 64层螺旋CT脑灌注成像联合CT血管造影评价颅内外血管搭桥术后疗效%Assessment of cerebral internal and external vascular bypass graft in patients with single middle cerebral artery stenosis or occlusion by combining 64-row CT cerebral perfusion with angiography

    Institute of Scientific and Technical Information of China (English)

    陈天金; 朱栓庄; 温有信; 王耀彬; 韩向东; 白莹; 于旋

    2012-01-01

    Objective To assess the curative effect of cerebral internal and external vascular bypass graft in patients with sin -gle middle cerebral artery (MCA) stenosis or occlusion by combining 64 -row CT cerebral perfusion (CTP) with angiography ( CTA ). Methods Patients with middle cerebral artery stenosis or occlusion were recruited and underwent superficial temporal artery and mid -die cerebral artery(STA -MCA) bypass graft between March 2009 and Mar 2011. CTP and CTA examinations were performed in all patients before and after operation. The cerebral perfusion parameters were analyzed quantitatively and qualitatively . The origin, travel and anastomotic stoma of bypass grafts were evaluated by reconstructed CTA images . Results 46 patients were found with severe MCA stenosis or occlusion. The time to peak (TTP) and relative mean transit time (rMTT) images before therapy displayed the existence of perfusion delay. The relative cerebral blood flow (rCBF) and relative cerebral blood volume (rCRV) images did not change significantly. The decrease of TTP and rMTT after therapy was of statistical significance ( P 0.05). In reconstructed CTA images , 82 bridge vessels were well displayed, including double bridges in 39 patients. The accuracy of CTA examination was 96.5%. All the bypass grafts were well shown and the anastomotic stomas were unobstructed. Conclusions It is feasible to evaluate the curative effects of cerebral internal and ex — ternal vascular bypass graft by combining CTP images of cerebral perfusion after therapy with CTA images of cerebral internal and exter -nal bypass grafts.%目的 探讨64层螺旋CT脑灌注成像(CT perfusion,CTP)联合CT血管造影(CT angiography,CTA)评价单侧大脑中动脉(middle cerebral artery,MCA)重度狭窄(闭塞)颅内外血管搭桥术后疗效的可行性.方法 46例拟行颅内外血管搭桥术患者,术前、后均行CTP及CTA检查.计算脑灌注参数图,对治疗前后脑灌注参数进行定量和定性对

  20. Increased perfusion pressure enhances the expression of endothelin (ETB) and angiotensin II (AT1, AT2) receptors in rat mesenteric artery smooth muscle cells

    DEFF Research Database (Denmark)

    Lindstedt, Isak; Xu, Cang-Bao; Zhang, Yaping;

    2009-01-01

    and luminally perfused in a perfusion chamber. After either exposure to no ("organ culture" (0 mmHg)), normal (85/75 mmHg) or high pressure (160/150 mmHg) at constant flow for 1-17 h, the vessel segments were snap frozen and real-time polymerase chain reaction was performed to quantify the ET- and AT-receptor m......In the present study, we hypothesized that changes in perfusion pressure result in altered expression of mRNA and protein encoding for the ETA-, ETB-, AT1- and AT2-receptors in rat mesenteric vessels. Segments of the rat mesenteric artery were cannulated with glass micropipettes, pressurized......RNA content, or immersed in a fixative solution, dehydrated, frozen, cut in a cryostat and immunohistology stained for ET- and AT-receptor protein. The mRNA expressions of ETB and of AT2 were significantly enhanced in vessels exposed to high perfusion pressure, compared with normal and no perfusion pressure...

  1. Altered phase interactions between spontaneous blood pressure and flow fluctuations in type 2 diabetes mellitus: Nonlinear assessment of cerebral autoregulation

    Science.gov (United States)

    Hu, Kun; Peng, C. K.; Huang, Norden E.; Wu, Zhaohua; Lipsitz, Lewis A.; Cavallerano, Jerry; Novak, Vera

    2008-04-01

    Cerebral autoregulation is an important mechanism that involves dilatation and constriction in arterioles to maintain relatively stable cerebral blood flow in response to changes of systemic blood pressure. Traditional assessments of autoregulation focus on the changes of cerebral blood flow velocity in response to large blood pressure fluctuations induced by interventions. This approach is not feasible for patients with impaired autoregulation or cardiovascular regulation. Here we propose a newly developed technique-the multimodal pressure-flow (MMPF) analysis, which assesses autoregulation by quantifying nonlinear phase interactions between spontaneous oscillations in blood pressure and flow velocity during resting conditions. We show that cerebral autoregulation in healthy subjects can be characterized by specific phase shifts between spontaneous blood pressure and flow velocity oscillations, and the phase shifts are significantly reduced in diabetic subjects. Smaller phase shifts between oscillations in the two variables indicate more passive dependence of blood flow velocity on blood pressure, thus suggesting impaired cerebral autoregulation. Moreover, the reduction of the phase shifts in diabetes is observed not only in previously-recognized effective region of cerebral autoregulation (type 2 diabetes mellitus alters cerebral blood flow regulation over a wide frequency range and that this alteration can be reliably assessed from spontaneous oscillations in blood pressure and blood flow velocity during resting conditions. We also show that the MMPF method has better performance than traditional approaches based on Fourier transform, and is more suitable for the quantification of nonlinear phase interactions between nonstationary biological signals such as blood pressure and blood flow.

  2. Comparison of cerebral blood flow data obtained by computed tomography (CT) perfusion with that obtained by xenon CT using 320-row CT.

    Science.gov (United States)

    Takahashi, Satoshi; Tanizaki, Yoshio; Kimura, Hiroaki; Akaji, Kazunori; Kano, Tadashige; Suzuki, Kentaro; Takayama, Youhei; Kanzawa, Takao; Shidoh, Satoka; Nakazawa, Masaki; Yoshida, Kazunari; Mihara, Ban

    2015-03-01

    Cerebral blood flow (CBF) data obtained by computed tomography perfusion (CTP) imaging have been shown to be qualitative data rather than quantitative, in contrast with data obtained by other imaging methods, such as xenon CT (XeCT) imaging. Thus, interpatient comparisons of CBF values themselves obtained by CTP may be inaccurate. In this study, we have compared CBF ratios as well as CBF values obtained from CTP-CBF data to those obtained from XeCT-CBF data for the same patients to determine CTP-CBF parameters that can be used for interpatient comparisons. The data used in the present study were obtained as volume data using 320-row CT. The volume data were applied to an automated region of interest-determining software (3DSRT, version 3.5.2 ) and converted to 59 slices of 2 mm interval standardized images. In the present study, we reviewed 10 patients with occlusive cerebrovascular diseases (CVDs) undergoing both CTP and XeCT in the same period. Our study shows that ratios of CBF measurements, such as hemodynamic stress distribution (perforator-to-cortical flow ratio of middle cerebral artery [MCA] region) or the left/right ratio for the region of the MCA, calculated using CTP data have been shown to correlate well with the same ratios calculated using XeCT data. These results suggest that such CBF ratios could be useful for generating interpatient comparisons of CTP-CBF data obtained by 320-row CT among patients with occlusive CVD.

  3. Continuous Monitoring of Cerebrovascular Reactivity Using Pulse Waveform of Intracranial Pressure

    NARCIS (Netherlands)

    Aries, M.J.H.; Czosnyka, Marek; Budohoski, Karol P.; Kolias, Angelos G.; Radolovich, Danila K.; Lavinio, Andrea; Pickard, John D.; Smielewski, Peter

    2012-01-01

    Guidelines for the management of traumatic brain injury (TBI) call for the development of accurate methods for assessment of the relationship between cerebral perfusion pressure (CPP) and cerebral autoregulation and to determine the influence of quantitative indices of pressure autoregulation on out

  4. Effect of Low-Pressurized Perfusion with Different Concentration of Elastase on the Aneurysm Formation Rate in the Abdominal Aortic Aneurysm Model in Rabbits.

    Science.gov (United States)

    Nie, Maoxiao; Yan, Yunfeng; Li, Xinhe; Feng, Tingting; Zhao, Xin; Zhang, Mingduo; Zhao, Quanming

    2016-01-01

    Establishing an animal model of abdominal aortic aneurysm (AAA) is the key to study the pathogenesis and the pathophysiological features of AAAs. We investigated the effects of low-pressurized perfusion with different concentrations of elastase on aneurysm formation rate in the AAA model. Fifty male New Zealand white rabbits were randomly divided into A, B, C, D, and E groups. 10 μL of normal saline was perfused into the abdominal aorta in group A and 1 U/mL, 10 U/mL, 100 U/mL, or 200 U/mL of elastase was, respectively, perfused for the other four groups. All the animals were perfused for 7 min. Doppler ultrasound examinations of the abdominal aorta were performed before surgery and on day 14 after surgery. The rabbits were sacrificed and the perfused segment of the abdominal aorta was observed visually and after staining. The aneurysm formation rate of group A, group B, group C, group D, and group E was, respectively, 0%, 0%, 33.3%, 102.5-146.8%, and 241.5-255.2%. The survival rate of five groups was 90%, 90%, 90%, 90%, and 40%, respectively. So, we concluded that low-pressurized perfusion with 100 U/mL of elastase can effectively establish AAAs in rabbits with a high aneurysm formation rate.

  5. Comparison of four methods to evaluate the modifications of the cerebral perfusion in tomo-scintigraphy; Comparaison de quatre methodes d'evaluation des modifications de la perfusion cerebrale en tomoscintigraphie

    Energy Technology Data Exchange (ETDEWEB)

    Daboussi, A.; Julian, A. [Universite Paul-Sabatier, EA 3033, Radiopharmaceutiques et Traitement de l' Image, 31 - Toulouse (France); Daboussi, A.; Fourcade, O. [Centre Hospitalier Universitaire Purpan, GRC 48 Coordination Anesthesie-Reanimation, 31 - Toulouse (France); Julian, A.; Ouhayoun, E.; Esquerre, J.P.; Payoux, P. [Centre Hospitalier Universitaire Purpan, Service de Medecine Nucleaire, 31 - Toulouse (France); Tremoulet, M. [Centre Hospitalier Universitaire Purpan, Service de Neurochirurgie, 31 - Toulouse (France)

    2007-02-15

    Introduction: We compared four different methods to assess changes in cerebral blood flow in patients with normal pressure hydrocephalus using cerebral ECD SPECT before and after injection of acetazolamide. Material and methods: Eleven patients underwent cerebral SPECT before and after injection of 1 g of acetazolamide using a {sup 99m}Tc-ECD split-dose protocol with a first injection of 370 MBq and a second of 1 100 MBq. After reconstruction of volumes with Neurogam (Segami) software. we compared visual analysis to semi quantitative analysis provided by Neurogam software. ratios methods and parametric analysis under SPM99 and SPM2. Results: Visual analysis is immediate but frequently misleading. The contribution of Neurogam depends on the reader's skill and may be significant for non expert readers. The manual semi-automatic method is tedious and its results depend on the choice of the areas of interest and reference necessary for activity normalization. At last, the automatic method carried out by SPM is reliable for population analysis, but its efficiency for individual analysis remains to be evaluated. (authors)

  6. Effect of cerebral ventricles perfusion with morphiceptin and Met-enkephalin on trigemino-hypoglossal reflex in rats.

    Science.gov (United States)

    Zubrzycka, M; Fichna, J; Janecka, A

    2002-12-01

    Opioids administered by intracerebroventricular injections produce analgesic responses in rats. The present study was undertaken to investigate the effects of a highly selective mu-opioid receptor ligand morphiceptin on trigemino-hypoglossal reflex in rats. The analgesic effect of morphiceptin was compared with another opioid peptide, Met-enkephalin. With the experimental settings used in this study, we have demonstrated that both morphiceptin and Met-enkephalin show significant dose-dependent analgesic effects after i.c.v. administration in rats as assayed by trigemino-hypoglossal reflex test. The antinociceptive response to Met-enkephalin was short lasting and was observed 10 to 15 min after i.c.v. perfusion. Morphiceptin had a relatively longer duration of antinociceptive action, the effect was observed 20-50 min after i.c.v. perfusion. Neither morphiceptin nor Met-enkephalin produced antinociception after peripheral injections. The results of the present study indicate that both tested peptides act at mu-opioid receptors situated in the central nervous system. They also suggest that mu-opioid receptors present in the central nervous system are an important element of the trigemino-hypoglossal reflex arc. For that reason selective mu-opioid receptor ligands, like morphiceptin, inhibit the reflex more significantly.

  7. Cerebrovascular Pressure Reactivity in Children with TBI

    Directory of Open Access Journals (Sweden)

    Laurence Ducharme-Crevier

    2015-11-01

    Full Text Available Investigators from University of Melbourne, Australia, studied Pressure-Reactivity Index (PRx and optimal Cerebral Perfusion Pressure (CPP in 36 children aged between 6 months and 16 years treated for traumatic brain injury (TBI at the Royal Children's Hospital, Melbourne, from 2007 to 2013.

  8. Correlation between special brain area and blood perfusion in patients with cerebral infarction at convalescent period Feasibility for quantitative determination and estimation of learning and memory function

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Presently, clinic memory scale is used to evaluate learning memory ability in most studies,and the influence of difference in measurement condition of individuals exists.OBJECTIVE: To study the correlation between regional cerebral blood flow (rCBF) perfusion and learning memory function in special brain regions of patients with cerebral infarction at convalescent period,and to try to find out a method which can quantitatively evaluate learning ability.DESIGN: Case observation, and correlation analysis.SETTINGS: Shandong Institute for Behavioral Medicine; the Affiliated Hospital of Jining Medical College.PARTICIPANTS: Totally 70 patients with cerebral infarction admitted to Departtment of Neurology, Jining Medical College between January 2004 and December 2005 were involved. The involved patients, 58 male and 12 female, were averaged (52±3) years, and they were all right handed. They all met the diagnosis criteria instituted by the Fourth National Conference on Cerebrovascular Disease, and were confirmed as cerebral infarction by skull CT or MRI. Informed consents of detected items were obtained from all the patients and relatives.METHODS: When the patients were at convalescent period, their learning and memory ability were measured with" clinic memory scale (set A)". The 18 patients whose total mark over 100 were regarded as good learning memory function group; The 23 cases whose total mark less than 70 were regarded as poor learning memory function group. RCBF of hippocampus, nucleus amygdalae, temporal cortex and prefrontal lobe of patients between two groups were measured and compared by single photon emission computed tomography (SPECT). The total scores of the 18 good learning memory patients and 23 poor learning memory patients were taken as dependent variable Y, and their rCBFs of hippocampus, nucleus amygdale,temporal cortex and prefrontal lobe respectively as independent variable X for linear correlation analysis.MAIN OUTCOME MEASURES

  9. CT perfusion imaging in the management of posterior reversible encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Casey, S.O.; McKinney, A.; Teksam, M.; Liu, H.; Truwit, C.L. [Department of Radiology, University of Minnesota Medical School, 420 Delaware Street SE, Box 292, MN 55455, Minneapolis (United States)

    2004-04-01

    A 13-year-old girl with a renal transplant presented with hypertension and seizures. CT and MRI demonstrated typical bilateral parietal, occipital and posterior frontal cortical and subcortical edema, thought to represent posterior reversible encephalopathy syndrome. The cause was presumed to be hypertension. Antihypertensive therapy was started, lowering of the blood pressure in the range of 110-120 mmHg systolic. However, stable xenon (Xe) CT perfusion imaging revealed ischemia within the left parietal occipital region. The antihypertensive was adjusted which increased both the systolic and diastolic blood pressure by 31 mm Hg. The patient was re-imaged with Xe CT and was found to have resolution of the ischemic changes within the left parietal occipital region. In this report, we present a case in which stable Xe CT was used to monitor the degree of cerebral perfusion and guide titration of antihypertensive therapy. Such brain perfusion monitoring may have helped to prevent infarction of our patient. (orig.)

  10. Effects of dopamine infusion on cerebral blood flow, brain cell membrane function and energy metabolism in experimental Escherichia coli meningitis in the newborn piglet.

    OpenAIRE

    Park, Won Soon; Chang, Yun Sil; Shim, Jae Won; Kim, Mi Jung; Ko, Sun Young; Kim, Sung Shin; Hwang, Jong Hee; Choi, Chang Won; Lee, Munhyang

    2003-01-01

    In the present study, we tested whether maintenance of adequate cerebral perfusion pressure (CPP) by pharmacologically preventing systemic hypotension with dopamine infusion would prevent cerebral ischemia and attenuate energy depletion and neuronal injury even though intracranial pressure remains elevated in a newborn piglet meningitis model. Cerebral blood flow, measured at the end of the experiment using fluorescent microspheres, was significantly increased by dopamine infusion. The decrea...

  11. Improvements in the technique of vascular perfusion-fixation employing a fluorocarbon-containing perfusate and a peristaltic pump controlled by pressure feedback

    DEFF Research Database (Denmark)

    Rostgaard, J; Qvortrup, K; Poulsen, Steen Seier

    1993-01-01

    oxygenated fluorocarbon to glutaraldehyde perfusate-fixatives, enough oxygen is made accessible for cellular respiration as well as for the oxygen-consuming chemical reactions of glutaraldehyde with the tissue. Data on anaesthesia, operative manoeuvres, mechanical components of the system, preparation...

  12. Re-thinking resuscitation: Leaving blood pressure cosmetics behind and moving forward to permissive hypotension and a tissue perfusion-based approach

    NARCIS (Netherlands)

    M.W. Dünser (Martin); E.P. Takala; A. Brunauer (Andreas); J. Bakker (Jan)

    2013-01-01

    textabstractDefinitions of shock and resuscitation endpoints traditionally focus on blood pressures and cardiac output. This carries a high risk of overemphasizing systemic hemodynamics at the cost of tissue perfusion. In line with novel shock definitions and evidence of the lack of a correlation be

  13. Evaluation of a potential generator-produced PET tracer for cerebral perfusion imaging: single-pass cerebral extraction measurements and imaging with radiolabeled Cu-PTSM.

    Science.gov (United States)

    Mathias, C J; Welch, M J; Raichle, M E; Mintun, M A; Lich, L L; McGuire, A H; Zinn, K R; John, E K; Green, M A

    1990-03-01

    Copper(II) pyruvaldehyde bis(N4-methylthiosemicarbazone) (Cu-PTSM), copper(II) pyruvaldehyde bis(N4-dimethylthiosemicarbazone) (Cu-PTSM2), and copper(II) ethylglyoxal bis(N4-methylthiosemicarbazone) (Cu-ETSM), have been proposed as PET tracers for cerebral blood flow (CBF) when labeled with generator-produced 62Cu (t1/2 = 9.7 min). To evaluate the potential of Cu-PTSM for CBF PET studies, baboon single-pass cerebral extraction measurements and PET imaging were carried out with the use of 67Cu (t1/2 = 2.6 days) and 64Cu (t1/2 = 12.7 hr), respectively. All three chelates were extracted into the brain with high efficiency. There was some clearance of all chelates in the 10-50-sec time frame and Cu-PTSM2 continued to clear. Cu-PTSM and Cu-ETSM have high residual brain activity. PET imaging of baboon brain was carried out with the use of [64Cu]-Cu-PTSM. For comparison with the 64Cu brain image, a CBF (15O-labeled water) image (40 sec) was first obtained. Qualitatively, the H2(15)O and [64Cu]-Cu-PTSM images were very similar; for example, a comparison of gray to white matter uptake resulted in ratios of 2.42 for H2(15)O and 2.67 for Cu-PTSM. No redistribution of 64Cu was observed in 2 hr of imaging, as was predicted from the single-pass study results. Quantitative determination of blood flow using Cu-PTSM showed good agreement with blood flow determined with H2(15)O. This data suggests that [62Cu]-Cu-PTSM may be a useful generator-produced radiopharmaceutical for blood flow studies with PET.

  14. Normal cerebral perfusion of {sup 99m}Tc-ECD brain SPECT. Evaluation by an anatomical standardization technique

    Energy Technology Data Exchange (ETDEWEB)

    Kawashima, Ryuta; Koyama, Masamichi; Ito, Hiroshi; Yoshioka, Seiro; Sato, Kazunori; Ono, Shuichi; Goto, Ryoi; Sato, Tachio; Fukuda, Hiroshi [Tohoku Univ., Sendai (Japan). Inst. of Development, Aging and Cancer

    1996-01-01

    A single photon emitter labeled tracer, {sup 99m}Tc-ethyl cysteinate dimer ({sup 99m}Tc-ECD), has now been used for rCBF studies with SPECT. However, normal distribution pattern of this agent in the brain still remains unclear. Therefore, the specific purpose of this study was to investigate the normal distribution pattern of {sup 99m}Tc-ECD SPECT image. Regional cerebral distribution was measured with SPECT and 984{+-}17 MBq of {sup 99m}Tc-ECD in ten normal subjects. During the SPECT measurement, subjects were placed comfortably in a supine position with their eyes closed. Each SPECT image was anatomically standardized using a computerized brain atlas system of Roland et al. (HBA: Human Brain Atlas) and X-CT image. Anatomically standardized SPECT images were globally normalized to 100 count/voxel. Then, the mean and SD images of brain SPECT were calculated voxel-by-voxel basis. The highest radioactivity was found in the medial aspect of the occipital lobe. The results indicate that the normal distribution pattern of {sup 99m}Tc-ECD in the human brain may be not simply reflect the regional cerebral blood flow. (author).

  15. Evaluation on the Therapeutic Effects of Digital Acupoint Pressure for Obstetric Spastic Cerebral Palsy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    To probe the evaluation methods for effects of TCM treatment of cerebral palsy through clinical observation on the digital acupoint pressure in treating obstetric spastic cerebral palsy. From 1998-2003,40 cases of spastic cerebral palsy were treated with digital acupoint pressure therapy. Ten indexes including intelligence, language, salivation, hand-grasping, thumb-adduction, turnover, sitting, standing,walking, and scissors-gait were divided into the 4 grades of normal, mild abnormal, moderate abnormal,and severe abnormal (dysfunction), respectively marked as 6, 4, 2, and 0 point, with 2 points increased for improving each grade of each item after the treatment. Meanwhile, the ranges were recorded and evaluated before and after the treatment on shoulder-abduction, elbow-extension, wrist-extension,forearm-backward-rotation, hip-abduction, straight-leg-lifting, knee-extension, and ankle-dorsiflexion.Those with the improvement of 10° , 15° , 20° , 25° , and 30° in the range of movement of their contractured joints would obtain respectively 1, 2, 3, 4, and 5 points. There were significant differences before and after the treatment in the 18 items under observation except for intelligence, with obvious improvement shown after the treatment (P<0.01), the effective rate being 92.5%. The therapeutic criteria set in this research are well established in reflecting the functional improvements of the patient.

  16. Simulating technetium-99m cerebral perfusion studies with a three-dimensional Hoffman brain phantom. Collimator and filter selection in SPECT neuroimaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hee-Joung; Yang, Seoung-Oh; Moon, Dae-Hyuk; Lee, Hee-Kyung [Asan Medical Center, Seoul (Korea, Republic of); Karp, J.S.; Mozley, P.D.; Kung, H.F.; Alavi, A.

    1996-02-01

    The choice of a collimator and the selection of a filter can affect the quality of clinical SPECT images of the brain. The compromises that 4 different collimators make between spatial resolution and sensitivity were studied by imaging a three-dimensional Hoffman brain phantom. The planar data were acquired with each collimator on a three-headed SPECT system and were reconstructed with both a standard Butterworth filter and a Wiener pre-filter. The reconstructed images were then evaluated by specialists in nuclear medicine and were also quantitatively analyzed with specific regions of interest (ROI) in the brain. All observers preferred the Wiener filter reconstructed images regardless of the collimator used to acquire the planar images. With this filter, the ultrahigh-resolution fan-beam collimator was the most subjectively preferable and quantitatively produced the highest contrast ratios. The findings support suggestions that higher resolution collimators are preferable to higher sensitivity collimators, and indicate that fan-beam collimators are preferable to parallel-hole collimators for clinical SPECT studies of cerebral perfusion. The results also suggest that the Wiener filter enhances the quality of SPECT brain images regardless of which collimator is used to acquire the data. (author).

  17. Cerebral blood volume calculated by dynamic susceptibility contrast-enhanced perfusion MR imaging: preliminary correlation study with glioblastoma genetic profiles.

    Directory of Open Access Journals (Sweden)

    Inseon Ryoo

    Full Text Available PURPOSE: To evaluate the usefulness of dynamic susceptibility contrast (DSC enhanced perfusion MR imaging in predicting major genetic alterations in glioblastomas. MATERIALS AND METHODS: Twenty-five patients (M:F = 13∶12, mean age: 52.1±15.2 years with pathologically proven glioblastoma who underwent DSC MR imaging before surgery were included. On DSC MR imaging, the normalized relative tumor blood volume (nTBV of the enhancing solid portion of each tumor was calculated by using dedicated software (Nordic TumorEX, NordicNeuroLab, Bergen, Norway that enabled semi-automatic segmentation for each tumor. Five major glioblastoma genetic alterations (epidermal growth factor receptor (EGFR, phosphatase and tensin homologue (PTEN, Ki-67, O6-methylguanine-DNA methyltransferase (MGMT and p53 were confirmed by immunohistochemistry and analyzed for correlation with the nTBV of each tumor. Statistical analysis was performed using the unpaired Student t test, ROC (receiver operating characteristic curve analysis and Pearson correlation analysis. RESULTS: The nTBVs of the MGMT methylation-negative group (mean 9.5±7.5 were significantly higher than those of the MGMT methylation-positive group (mean 5.4±1.8 (p = .046. In the analysis of EGFR expression-positive group, the nTBVs of the subgroup with loss of PTEN gene expression (mean: 10.3±8.1 were also significantly higher than those of the subgroup without loss of PTEN gene expression (mean: 5.6±2.3 (p = .046. Ki-67 labeling index indicated significant positive correlation with the nTBV of the tumor (p = .01. CONCLUSION: We found that glioblastomas with aggressive genetic alterations tended to have a high nTBV in the present study. Thus, we believe that DSC-enhanced perfusion MR imaging could be helpful in predicting genetic alterations that are crucial in predicting the prognosis of and selecting tailored treatment for glioblastoma patients.

  18. Normal cerebral perfusion of {sup 99m}Tc-HMPAO brain SPECT. Evaluation by an anatomical standardization technique

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, Masamichi; Kawashima, Ryuta; Ito, Hiroshi [Tohoku Univ., Sendai (Japan). Inst. of Development, Aging and Cancer] [and others

    1995-09-01

    Single photon labeled tracer {sup 99m}Tc-hexamethyl-propylene amine oxime (HMPAO) has been used for rCBF studies by SPECT. However, normal perfusion pattern of this agent still remains unclear. The purpose of this study was to investigate normal {sup 99m}Tc-HMPAO SPECT image voxel by voxel. Eighteen male subjects without any prior or present history of medical illness participated in this study. All SPECT images were globally normalized to 100 count/voxel. Each subject had an X-ray CT scan at the same day of SPECT measurement. All subjects had normal X-ray CT scans. The standard anatomical structures of the computerized brain atlas of Roland et al. were fitted to X-ray CT images of a subject by linear and non-linear parameters. These parameters were subsequently used to transform SPECT images of the subject. After the anatomical standardization, mean and SD images of eight standardized images were calculated voxel-by-voxel basis. In the mean image, following structures showed relatively higher radioactivity; the putamen, the cerebellum, and the frontal lobe. In addition, the occipital lobe, parietal lobe, frontal lobe, and the putamen showed large degree of SD. Anatomical standardization of SPECT images may be useful as a reference to diagnose and evaluate various brain disorders. (author).

  19. Absolute Cerebral Blood Flow Infarction Threshold for 3-Hour Ischemia Time Determined with CT Perfusion and 18F-FFMZ-PET Imaging in a Porcine Model of Cerebral Ischemia.

    Science.gov (United States)

    Wright, Eric A; d'Esterre, Christopher D; Morrison, Laura B; Cockburn, Neil; Kovacs, Michael; Lee, Ting-Yim

    2016-01-01

    CT Perfusion (CTP) derived cerebral blood flow (CBF) thresholds have been proposed as the optimal parameter for distinguishing the infarct core prior to reperfusion. Previous threshold-derivation studies have been limited by uncertainties introduced by infarct expansion between the acute phase of stroke and follow-up imaging, or DWI lesion reversibility. In this study a model is proposed for determining infarction CBF thresholds at 3hr ischemia time by comparing contemporaneously acquired CTP derived CBF maps to 18F-FFMZ-PET imaging, with the objective of deriving a CBF threshold for infarction after 3 hours of ischemia. Endothelin-1 (ET-1) was injected into the brain of Duroc-Cross pigs (n = 11) through a burr hole in the skull. CTP images were acquired 10 and 30 minutes post ET-1 injection and then every 30 minutes for 150 minutes. 370 MBq of 18F-FFMZ was injected ~120 minutes post ET-1 injection and PET images were acquired for 25 minutes starting ~155-180 minutes post ET-1 injection. CBF maps from each CTP acquisition were co-registered and converted into a median CBF map. The median CBF map was co-registered to blood volume maps for vessel exclusion, an average CT image for grey/white matter segmentation, and 18F-FFMZ-PET images for infarct delineation. Logistic regression and ROC analysis were performed on infarcted and non-infarcted pixel CBF values for each animal that developed infarct. Six of the eleven animals developed infarction. The mean CBF value corresponding to the optimal operating point of the ROC curves for the 6 animals was 12.6 ± 2.8 mL·min-1·100g-1 for infarction after 3 hours of ischemia. The porcine ET-1 model of cerebral ischemia is easier to implement then other large animal models of stroke, and performs similarly as long as CBF is monitored using CTP to prevent reperfusion.

  20. Absolute Cerebral Blood Flow Infarction Threshold for 3-Hour Ischemia Time Determined with CT Perfusion and 18F-FFMZ-PET Imaging in a Porcine Model of Cerebral Ischemia.

    Directory of Open Access Journals (Sweden)

    Eric A Wright

    Full Text Available CT Perfusion (CTP derived cerebral blood flow (CBF thresholds have been proposed as the optimal parameter for distinguishing the infarct core prior to reperfusion. Previous threshold-derivation studies have been limited by uncertainties introduced by infarct expansion between the acute phase of stroke and follow-up imaging, or DWI lesion reversibility. In this study a model is proposed for determining infarction CBF thresholds at 3hr ischemia time by comparing contemporaneously acquired CTP derived CBF maps to 18F-FFMZ-PET imaging, with the objective of deriving a CBF threshold for infarction after 3 hours of ischemia. Endothelin-1 (ET-1 was injected into the brain of Duroc-Cross pigs (n = 11 through a burr hole in the skull. CTP images were acquired 10 and 30 minutes post ET-1 injection and then every 30 minutes for 150 minutes. 370 MBq of 18F-FFMZ was injected ~120 minutes post ET-1 injection and PET images were acquired for 25 minutes starting ~155-180 minutes post ET-1 injection. CBF maps from each CTP acquisition were co-registered and converted into a median CBF map. The median CBF map was co-registered to blood volume maps for vessel exclusion, an average CT image for grey/white matter segmentation, and 18F-FFMZ-PET images for infarct delineation. Logistic regression and ROC analysis were performed on infarcted and non-infarcted pixel CBF values for each animal that developed infarct. Six of the eleven animals developed infarction. The mean CBF value corresponding to the optimal operating point of the ROC curves for the 6 animals was 12.6 ± 2.8 mL·min-1·100g-1 for infarction after 3 hours of ischemia. The porcine ET-1 model of cerebral ischemia is easier to implement then other large animal models of stroke, and performs similarly as long as CBF is monitored using CTP to prevent reperfusion.

  1. Practical and comprehensive guidelines for bedside cerebral hemometabolic multitherapeutic optimization

    Directory of Open Access Journals (Sweden)

    Cruz Julio

    2002-01-01

    Full Text Available In recent years, noncomprehensive "guidelines" were proposed for the management of severe acute brain injuries, focusing strictly on two approaches: 1 to maintain cerebral perfusion pressure anywhere above 70 mm Hg; and 2 to maintain arterial carbon dioxide tension levels above 30 torr. Strictly following these propositions, a recently reported prospective controlled study addressed mortality rates of no less than 75-76%, far worse than mortality rates reported before those "guidelines" were published. As a humanitarian alternative, the present comprehensive guidelines are aimed at addressing practical bedside strategies to manage no only intracranial pressure and cerebral perfusion pressure but also cerebral extraction of oxygen, based on solid previously reported papers which revealed the lowest mortality rates (below 15% in the pertinent literature, in recent years.

  2. Skin perfusion pressure measured by isotope washout in legs with arterial occlusive disease. Evaluation of different tracers, comparison to segmental systolic pressure, angiography and transcutaneous oxygen tension and variations during changes in systemic blood pressure

    DEFF Research Database (Denmark)

    Holstein, P; Trap-Jensen, J; Bagger, H

    1983-01-01

    The skin perfusion pressure (SPP) measured as the isotope washout cessation external pressure is valuable in selection of major amputation level. Five methodological investigations important to clinical use were carried out: (1) In five normal legs and 10 legs with arterial occlusive disease (AOD...... in legs with arterial occlusions at two levels or more; (4) In 47 legs with AOD, the SPP on the calf or on the thigh was compared with transcutaneously measured pO2. The two different methods correlated statistically significant, but the scatter was great; (5) During induced variations in systemic blood...... pressure in seven patients (12 legs with AOD), the segmental SPP and the segmental systolic blood pressure were found on average to vary in proportion with intra-arterial mean and systolic pressure respectively; however, this proportional relationship was not valid for the individual leg. It is concluded...

  3. Paradoxical presentation of orthostatic headache associated with increased intracranial pressure in patients with cerebral venous thrombosis

    Directory of Open Access Journals (Sweden)

    Jung B Kim

    2013-01-01

    Full Text Available Headache is the most common symptom of cerebral venous thrombosis (CVT; however, the detailed underlying mechanisms and characteristics of headache in CVT have not been well described. Here, we report two cases of CVT whose primary and lasting presentation was orthostatic headache, suggestive of decreased intracranial pressure. Contrary to our expectations, the headaches were associated with elevated cerebrospinal fluid (CSF pressure. Magnetic resonance imaging and magnetic resonance venography showed characteristic voiding defects consistent with CVT. We suggest that orthostatic headache can be developed in a condition of decreased intracranial CSF volume in both intracranial hypotensive and intracranial hypertensive states. In these cases, orthostatic headache in CVT might be caused by decreased intracranial CSF volume that leads to the inferior displacement of the brain and traction on pain-sensitive intracranial vessels, despite increased CSF pressure on measurement. CVT should be considered in the differential diagnosis when a patient complains of orthostatic headache.

  4. MRI evidence for preserved regulation of intracranial pressure in patients with cerebral arteriovenous malformations

    Energy Technology Data Exchange (ETDEWEB)

    Meinel, Felix G.; Fischer, Judith; Pomschar, Andreas; Wöhrle, Natalie; Koerte, Inga K.; Steffinger, Denise [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistr. 15, 81377 Munich (Germany); Laubender, Rüdiger P. [Institute of Medical Informatics, Biometry and Epidemiology, Ludwig-Maximilians-University, Marchioninistr. 15, 81377 Munich (Germany); Muacevic, Alexander [European Cyberknife Center Munich, 81377 Munich (Germany); Reiser, Maximilian F. [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistr. 15, 81377 Munich (Germany); Alperin, Noam [Department of Radiology, Miller School of Medicine, University of Miami, Miami, FL 33136 (United States); Ertl-Wagner, Birgit, E-mail: birgit.ertl-wagner@med.uni-muenchen.de [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Marchioninistr. 15, 81377 Munich (Germany)

    2014-08-15

    Purpose: The purpose of this study was to investigate intracranial pressure and associated hemo- and hydrodynamic parameters in patients with cerebral arteriovenous malformations AVMs. Methods: Thirty consecutive patients with arteriovenous malformations (median age 38.7 years, 27/30 previously treated with radiosurgery) and 30 age- and gender-matched healthy controls were investigated on a 3.0 T MR scanner. Nidus volume was quantified on dynamic MR angiography. Total arterial cerebral blood flow (tCBF), venous outflow as well as aqueductal and craniospinal stroke volumes were obtained using velocity-encoded cine-phase contrast MRI. Intracranial volume change during the cardiac cycle was calculated and intracranial pressure (ICP) was derived from systolic intracranial volume change (ICVC) and pulse pressure gradient. Results: TCBF was significantly higher in AVM patients as compared to healthy controls (median 799 vs. 692 mL/min, p = 0.007). There was a trend for venous flow to be increased in both the ipsilateral internal jugular vein (IJV, 282 vs. 225 mL/min, p = 0.16), and in the contralateral IJV (322 vs. 285 mL/min, p = 0.09), but not in secondary veins. There was no significant difference in median ICP between AVM patients and control subjects (6.9 vs. 8.6 mmHg, p = 0.30) and ICP did not correlate with nidus volume in AVM patients (ρ = −0.06, p = 0.74). There was a significant positive correlation between tCBF and craniospinal CSF stroke volume (ρ = 0.69, p = 0.02). Conclusions: The elevated cerebral blood flow in patients with AVMs is drained through an increased flow in IJVs but not secondary veins. ICP is maintained within ranges of normal and does not correlate with nidus volume.

  5. [Automatic regulator of venous pressure and venous outflow in the perfusion system].

    Science.gov (United States)

    Smirnov, L M; Levinskiĭ, M M; Kharnas, S Sh; Cherniak, V A

    1976-01-01

    A scheme for automatic regulation of the venous pressure and venous blood outflow during extracorporeal circulation is proposed. The system consists of a photoelectric sensor placed on a tube led out of the major venous trunkline, a converter and an electromechanical eccentric clamp that compresses the venous trunkline, all of which secures stabilization of the controlled values.

  6. Early effects of combretastatin-A4 disodium phosphate on tumor perfusion and interstitial fluid pressure

    DEFF Research Database (Denmark)

    Ley, C.D.; Horsman, Michael Robert; Kristjansen, P.E.G.

    2007-01-01

    of the tumor vasculature. It has been proposed that increased permeability causes a transient increase in interstitial fluid pressure (IFP), which in turn could collapse intratumoral blood vessels. We examined the immediate effects of CA4DP on tumor IFP in C3H mammary carcinoma. Mice were treated with 100 mg...

  7. Mean arterial pressure change associated with cerebral blood flow in healthy older adults.

    Science.gov (United States)

    Deverdun, Jeremy; Akbaraly, Tasnime N; Charroud, Celine; Abdennour, Meriem; Brickman, Adam M; Chemouny, Stephane; Steffener, Jason; Portet, Florence; Bonafe, Alain; Stern, Yaakov; Ritchie, Karen; Molino, François; Le Bars, Emmanuelle; Menjot de Champfleur, Nicolas

    2016-10-01

    We investigate over a 12-year period the association between regional cerebral blood flow (CBF) and cardiovascular risk factors in a prospective cohort of healthy older adults (81.96 ± 3.82 year-old) from the Cognitive REServe and Clinical ENDOphenotype (CRESCENDO) study. Cardiovascular risk factors were measured over 12 years, and gray matter CBF was measured at the end of the study from high-resolution magnetic resonance imaging using arterial spin labeling. The association between cardiovascular risk factors, their long-term change, and CBF was assessed using multivariate linear regression models. Women were observed to have higher CBF than men (p < 0.05). Increased mean arterial pressure (MAP) over the 12-year period was correlated with a low cerebral blood flow (p < 0.05, R(2) = 0.21), whereas no association was detected between CBF and MAP at the time of imaging. High levels of glycemia tended to be associated with low cerebral blood flow values (p < 0.05). Age, alcohol consumption, smoking status, body mass index, history of cardiovascular disease, and hypertension were not associated with CBF. Our main result suggests that change in MAP is the most significant predictor of future CBF in older adults.

  8. High blood pressure and cerebral white matter lesion progression in the general population.

    Science.gov (United States)

    Verhaaren, Benjamin F J; Vernooij, Meike W; de Boer, Renske; Hofman, Albert; Niessen, Wiro J; van der Lugt, Aad; Ikram, M Arfan

    2013-06-01

    High blood pressure is considered an important risk factor for cerebral white matter lesions (WMLs) in the aging population. In a longitudinal population-based study of 665 nondemented persons, we investigated the longitudinal relationship of systolic blood pressure, diastolic blood pressure, and pulse pressure with annual progression of WMLs. Means of blood pressure were calculated over a 5-year period before longitudinal MRI scanning. WML progression was subsequently measured on 2 scans 3.5 years apart. We performed analyses with linear regression models and evaluated adjustments for age, sex, cardiovascular risk factors, and baseline WML volume. In addition, we evaluated whether treatment of hypertension is related to less WML progression. Both systolic and diastolic blood pressures were significantly associated with annual WML progression (regression coefficient [95% confidence interval], 0.08 [0.03; 0.14] mL/y and 0.09 [0.03; 0.15] mL/y per SD increase in systolic and diastolic blood pressure, respectively). Pulse pressure was also significantly associated with WML progression, but not independent from hypertension. After adjustment for baseline WML volume, only systolic blood pressure remained significantly associated: 0.05 (0.00; 0.09) mL/y per SD increase. People with uncontrolled untreated hypertension had significantly more WML progression than people with uncontrolled treated hypertension (difference [95% confidence interval], 0.12 [0.00; 0.23] mL/y). The present study further establishes high blood pressure to precede WMLs and implies that hypertension treatment could reduce WML progression in the general population.

  9. Comparison of Intraocular Pressure, Blood Pressure, Ocular Perfusion Pressure and Blood Flow Fluctuations During Dorzolamide Versus Timolol Add-On Therapy in Prostaglandin Analogue Treated Glaucoma Subjects

    Directory of Open Access Journals (Sweden)

    Ruta Barsauskaite

    2012-03-01

    Full Text Available Objective: To compare the effects of dorzolamide and timolol add-on therapy in open-angle glaucoma (OAG patients previously treated with prostaglandin analogue (Pg, by evaluating fluctuations in the intraocular (IOP, blood (BP, ocular perfusion pressures (OPP and retrobulbar blood flow (RBF parameters. Methods: 35 OAG patients (35 eyes, 31 women (88.6% age 63.3 (8.9 years were evaluated in a 3 month randomized, cross-over, single-masked study. During the experiments BP, heart rate, IOP and OPP were assessed 4 times per day (8–12–16–20 h. RBF was measured twice per day (8–20 h using Color Doppler imaging in the ophthalmic (OA, central retinal (CRA, nasal (nSPCA and temporal (tSPCA posterior ciliary arteries. In each vessel, peak systolic velocity (PSV and end-diastolic velocity (EDV were assessed and vascular resistance (RI calculated. Results: Both add-on therapies lowered IOP in a statistically significant manner from 15.7 ± 2.4 mmHg at latanoprost baseline to 14.9 ± 2.2 mmHg using dorzolamide (p < 0.001 and 14.2 ± 1.9 mmHg using timolol (p < 0.001. The IOP lowering effect was statistically significant at 20 h, favoring timolol as compared to dorzolamide (1.4 ± 2.4 vs. 0.2 ± 2.1 mmHg, (p < 0.05. Dorzolamide add-on therapy showed smaller IOP (2.0 ± 1.4, SPP (13.3 ± 7.9, systolic BP (13.5 ± 8.7 and diastolic BP (8.4 ± 5.4 fluctuations as compared to both latanoprost baseline or timolol add-on therapies. Higher difference between morning and evening BP was correlated to decreased evening CRA EDV in the timolol group (c = −0.41; p = 0.01. With increased MAP in the morning or evening hours, we found increased evening OA RI in timolol add-on group (c = 0.400, p = 0.02; c = 0.513, p = 0.002 accordingly. Higher MAP fluctuations were related to impaired RBF parameters during evening hours-decreased CRA EDV (c = −0.408; p = 0.01, increased CRA RI (c = 0.576; p < 0.001 and tSPCA RI (c = 0.356; p = 0.04 in the dorzolamide group and

  10. Association of Cerebral Amyloidosis, Blood Pressure, and Neuronal Injury with Late-life Onset Depression

    Directory of Open Access Journals (Sweden)

    Min Soo Byun

    2016-10-01

    Full Text Available Previous literature suggests that Alzheimer’s disease (AD process may contribute to late-life onset depression (LLOD. Therefore, we investigated the association of LLOD with cerebral amyloidosis and neuronal injury, the two key brain changes in AD, along with vascular risks. Twenty nine non-demented individuals who first experienced major depressive disorder (MDD after age of 60 years were included as LLOD subjects, and 27 non-demented elderly individuals without lifetime experience of MDD were included as normal controls (NC. Comorbid mild cognitive impairment (MCI was diagnosed in 48% of LLOD subjects and in 0% of NC. LLOD, irrespective of comorbid MCI diagnosis, was associated with prominent prefrontal cortical atrophy. Compared to NC, LLOD subjects with comorbid MCI (LLODMCI showed increased cerebral 11C-Pittsburg compound B (PiB retention and plasma beta-amyloid 1-40 and 1-42 peptides, as measures of cerebral amyloidosis; and, such relationship was not observed in overall LLOD or LLOD without MCI (LLODwoMCI. LLOD subjects, particularly the LLODwoMCI, had higher systolic blood pressure (SBP than NC. When analyzed in the same multiple logistic regression model that included prefrontal gray matter (GM density, cerebral amyloidosis and SBP as independent variables, only prefrontal GM density showed a significant independent association with LLOD regardless of MCI comorbidity status. Our findings suggest AD process might be related to LLOD via prefrontal neuronal injury in the MCI stage, whereas vascular processes—SBP elevation, in particular—are associated with LLOD via prefrontal neuronal injury even in cognitively intact or less impaired individuals.

  11. Association of Cerebral Amyloidosis, Blood Pressure, and Neuronal Injury with Late-Life Onset Depression

    Science.gov (United States)

    Byun, Min Soo; Choe, Young Min; Sohn, Bo Kyung; Yi, Dahyun; Han, Ji Young; Park, Jinsick; Choi, Hyo Jung; Baek, Hyewon; Lee, Jun Ho; Kim, Hyun Jung; Kim, Yu Kyeong; Yoon, Eun Jin; Sohn, Chul-Ho; Woo, Jong Inn; Lee, Dong Young

    2016-01-01

    Previous literature suggests that Alzheimer's disease (AD) process may contribute to late-life onset depression (LLOD). Therefore, we investigated the association of LLOD with cerebral amyloidosis and neuronal injury, the two key brain changes in AD, along with vascular risks. Twenty nine non-demented individuals who first experienced major depressive disorder (MDD) after age of 60 years were included as LLOD subjects, and 27 non-demented elderly individuals without lifetime experience of MDD were included as normal controls (NC). Comorbid mild cognitive impairment (MCI) was diagnosed in 48% of LLOD subjects and in 0% of NC. LLOD, irrespective of comorbid MCI diagnosis, was associated with prominent prefrontal cortical atrophy. Compared to NC, LLOD subjects with comorbid MCI (LLODMCI) showed increased cerebral 11C-Pittsburg compound B (PiB) retention and plasma beta-amyloid 1–40 and 1–42 peptides, as measures of cerebral amyloidosis; and, such relationship was not observed in overall LLOD or LLOD without MCI (LLODwoMCI). LLOD subjects, particularly the LLODwoMCI, had higher systolic blood pressure (SBP) than NC. When analyzed in the same multiple logistic regression model that included prefrontal gray matter (GM) density, cerebral amyloidosis, and SBP as independent variables, only prefrontal GM density showed a significant independent association with LLOD regardless of MCI comorbidity status. Our findings suggest AD process might be related to LLOD via prefrontal neuronal injury in the MCI stage, whereas vascular processes—SBP elevation, in particular—are associated with LLOD via prefrontal neuronal injury even in cognitively intact or less impaired individuals. PMID:27790137

  12. Skin perfusion pressure measured by isotope washout in legs with arterial occlusive disease. Evaluation of different tracers, comparison to segmental systolic pressure, angiography and transcutaneous oxygen tension and variations during changes in systemic blood pressure

    DEFF Research Database (Denmark)

    Holstein, P; Trap-Jensen, J; Bagger, H;

    1983-01-01

    digit (strain gauge technique). The two different methods correlated statistically significant at all four levels, but the systolic blood pressures were higher than the SPP in particular in diabetic legs; (3) Angiograms in 35 legs with AOD showed that the SPP on the ankle was only consistently decreased......The skin perfusion pressure (SPP) measured as the isotope washout cessation external pressure is valuable in selection of major amputation level. Five methodological investigations important to clinical use were carried out: (1) In five normal legs and 10 legs with arterial occlusive disease (AOD......Hg (range 18-98) (P less than 0.02). The average washout constant for the three different tracers were approximately equal and correlated statistically significant with the SPP; (2) In 59 legs with AOD, segmental SPP was compared to segmental systolic blood pressures on the thigh, calf, ankle and first...

  13. Cerebral perfusion (HMPAO-SPECT) in patients with depression with cognitive impairment versus those with mild cognitive impairment and dementia of Alzheimer's type: a semiquantitative and automated evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Staffen, W.; Bergmann, J.; Schoenauer, U.; Kronbichler, M.; Golaszewski, S.; Ladurner, G. [Paracelsus Medical University, Christian-Doppler-Clinic, Department of Neurology, and Center of Cognitive Research Salzburg, Salzburg (Austria); Zauner, H. [Rehabilitation Center of the Pensionsversicherungsanstalt, Grossgmain (Austria)

    2009-05-15

    Comparative evaluation of regional brain perfusion measured by HMPAO-SPECT of patients with mild cognitive impairment (MCI), dementia of Alzheimer's type (DAT) and depression with cognitive impairment (DCI). A total of 736 patients were investigated because of suspected cognitive dysfunction. After exclusion of patients with other forms of dementia than DAT or relevant accompanying disorders, SPECT data from 149 MCI, 131 DAT and 127 DCI patients, and 123 controls without any cognitive impairment, were analysed. Relative cerebral blood flow of 34 anatomical regions was assessed with automated analysis software (BRASS). Calculation of global forebrain perfusion discriminated demented from nondemented patients. Compared to controls DCI patients showed hypoperfusion of the thalamus, lentiform nucleus and medial temporal cortex. MCI patients differed significantly from controls concerning perfusion in both hemispheric temporal and parietal areas, and in the (right hemispheric) posterior part of the cingulate gyrus. MCI and DCI patients differed in the parietal, temporal superior and right hemispheric cingulate gyrus posterior cortices. Global forebrain and regional perfusion was more extensively reduced in DAT patients and discriminated them from controls, and MCI and DCI patients. Frontal perfusion disturbance was only present in DAT patients. Automated analysis of HMPAO-SPECT data from MCI patients showed significant perfusion deficits in regions also involved in DAT patients, but ROC analysis demonstrated only moderate sensitivity and specificity for differentiating DAT patients from controls and DCI patients. Frontal hypoperfusion seems to correspond with conversion from MCI to DAT. Finally, the results in DCI patients again raise the question of depression as an early symptom of neurodegeneration. (orig.)

  14. Effects of Ginkgo biloba on cerebral blood flow assessed by quantitative MR perfusion imaging: a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Mashayekh, Ameneh; Pham, Dzung L.; Yousem, David M.; Dizon, Mercedes; Barker, Peter B.; Lin, Doris D.M. [Johns Hopkins University School of Medicine, Department of Radiology, Division of Neuroradiology, Baltimore, MD (United States)

    2011-03-15

    Extract of Ginkgo biloba (EGb), a dietary supplement used for a number of conditions including dementia, has been suggested to increase cerebral blood flow (CBF). The purpose of this study was to determine if changes in CBF could be detected by dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSC-MRI) in elderly human subjects taking EGb. DSC-MRI was performed in nine healthy men (mean age 61 {+-} 10 years) before and after 4 weeks of 60 mg EGb taken twice daily. One subject underwent six consecutive scans to evaluate intrasubject reproducibility. CBF values were computed before and after EGb, and analyzed at three different levels of spatial resolution, using voxel-based statistical parametric mapping (SPM), and regions of interest in different lobes, and all regions combined. Normalized intrasubject CBF (nCBF) measurements had a standard deviation of 7% and 4% in gray and white matter (WM) regions, respectively. SPM using an uncorrected, voxel-level threshold of P {<=} 0.001 showed a small CBF increase in the left parietal-occipital region. CBF in individual lobar regions did not show any significant change post-EGb, but all regions combined showed a significant increase of non-normalized CBF after EGb (15% in white and 13% in gray matter, respectively, P {<=} 0.0001). nCBF measured by DSC-MRI has good intrasubject reproducibility. In this small cohort of normal elderly individuals, a mild increase in CBF is found in the left parietal-occipital WM after EGb, as well as a small but statistically significant increase in global CBF. (orig.)

  15. Assessment of Cerebral Hemodynamic Changes in Pediatric Patients with Moyamoya Disease Using Probabilistic Maps on Analysis of Basal/Acetazolamide Stress Brain Perfusion SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ho Young; Lee, Jae Sung; Kim, Seung Ki; Wang, Kyu Chang; Cho, Byung Kyu; Chung, June Key; Lee, Myung Chul; Lee, Dong Soo [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2008-06-15

    To evaluate the hemodynamic changes and the predictive factors of the clinical outcome in pediatric patients with moyamoya disease, we analyzed pre/post basal/acetazolamide stress brain perfusion SPECT with automated volume of interest (VOIs) method. Total fifty six (M:F=33:24, age 6.7{+-}3.2 years) pediatric patients with moyamoya disease, who underwent basal/acetazolamide stress brain perfusion SPECT within 6 before and after revascularization surgery (encephalo-duro-arterio-synangiosis (EDAS) with frontal encephalo-galeo-synangiosis (EGS) and EDAS only followed on contralateral hemisphere), and followed-up more than 6 months after post-operative SPECT, were included. A mean follow-up period after post-operative SPECT was 33{+-}21 months. Each patient's SPECT image was spatially normalized to Korean template with the SPM2. For the regional count normalization, the count of pons was used as a reference region. The basal/acetazolamide-stressed cerebral blood flow (CBF), the cerebral vascular reserve index (CVRI), and the extent of area with significantly decreased basal/acetazolamide- stressed rCBF than age-matched normal control were evaluated on both medial frontal, frontal, parietal, occipital lobes, and whole brain in each patient's images. The post-operative clinical outcome was assigned as good, poor according to the presence of transient ischemic attacks and/or fixed neurological deficits by pediatric neurosurgeon. In a paired t-test, basal/acetazolamide-stressed rCBF and the CVRI were significantly improved after revascularization (p<0.05). The significant difference in the pre-operative basal/acetazolamide-stressed rCBF and the CVRI between the hemispheres where EDAS with frontal EGS was performed and their contralateral counterparts where EDAS only was done disappeared after operation (p<0.05). In an independent student t-test, the pre-operative basal rCBF in the medial frontal gyrus, the post-operative CVRI in the frontal lobe and the parietal

  16. Modelling of cerebral hyper-perfusion after chronic forebrain ischemia in rats%大鼠慢性前脑缺血解除后脑过度灌注模型的建立

    Institute of Scientific and Technical Information of China (English)

    肖玮; 王天龙; 李俊发; 赵磊; 于培兰; 孔萃萃

    2011-01-01

    目的 建立大鼠慢性前脑缺血基础上的脑过度灌注模型.方法 选取雄性Wistar大鼠72只依随机数字表均分为两个模型建造组.缺血模型采用双侧颈总动脉结扎,随机数字表分为空白对照、假手术组、缺血2周组、缺血4周组,每组9只,结扎前后分别测定脑额叶血流、比较各组行为学评分、脑梗死面积.过度灌注模型是在缺血模型基础上,再灌注同时经尾静脉持续输注去氧肾上腺素4μg·kg-1·min-1,使再灌注后脑额叶血流超过基础值的200%.随机分为空白对照组、盐水组、过度灌注0.5 h组、过度灌注2 h组,每组9只,再灌注前后分别测定脑额叶血流,比较各组行为学评分、血脑屏障通透性、脑干湿重比值.结果 大鼠双侧颈动脉结扎后前脑血流减少可达67%±2%,脑过度灌注组与盐水输注组的脑血流变化值差异有统计学意义(P<0.01).缺血2周组的神经功能评分、脑梗死面积与正常对照组差异无统计学意义,缺血4周组的脑梗死面积与正常对照组差异有统计学意义.脑过度灌注2 h组的血脑屏障通透性改变有统计学意义(P<0.05).结论 结扎大鼠双侧颈总动脉2周后脑过度灌注2 h可较好地建立大鼠脑过度灌注综合征模型.%Objective To establish the cerebral hyper-perfusion model after chronic forebrain ischemia in rats. Methods A total of 72 male rats were equally randomized into 2 modeling groups. The ligation of bilateral common carotid artery could induce chronic forebrain ischemia. And 36 rats were randomly grouped by ischemia duration: control group ( n = 9 ), sham group ( n = 9 ), 2-wcek ischemia group ( n = 9 ) and 4-wcek ischemia group ( n = 9 ). The blood flow in frontal lobe was measured at pre- and post-ligation. The neurological score and cerebral infarction area were also compared among the groups. The min-1 via tail vein to produce cerebrally hyperperfused blood flow rate over 200% of baseline

  17. Redox signaling via oxidative inactivation of PTEN modulates pressure-dependent myogenic tone in rat middle cerebral arteries.

    Directory of Open Access Journals (Sweden)

    Debebe Gebremedhin

    Full Text Available The present study examined the level of generation of reactive oxygen species (ROS and roles of inactivation of the phosphatase PTEN and the PI3K/Akt signaling pathway in response to an increase in intramural pressure-induced myogenic cerebral arterial constriction. Step increases in intraluminal pressure of cannulated cerebral arteries induced myogenic constriction and concomitant formation of superoxide (O2 (.- and its dismutation product hydrogen peroxide (H2O2 as determined by fluorescent HPLC analysis, microscopic analysis of intensity of dihydroethidium fluorescence and attenuation of pressure-induced myogenic constriction by pretreatment with the ROS scavenger 4,hydroxyl-2,2,6,6-tetramethylpiperidine1-oxyl (tempol or Mito-tempol or MitoQ in the presence or absence of PEG-catalase. An increase in intraluminal pressure induced oxidation of PTEN and activation of Akt. Pharmacological inhibition of endogenous PTEN activity potentiated pressure-dependent myogenic constriction and caused a reduction in NPo of a 238 pS arterial KCa channel current and an increase in [Ca(2+]i level in freshly isolated cerebral arterial muscle cells (CAMCs, responses that were attenuated by Inhibition of the PI3K/Akt pathway. These findings demonstrate an increase in intraluminal pressure induced increase in ROS production triggered redox-sensitive signaling mechanism emanating from the cross-talk between oxidative inactivation of PTEN and activation of the PI3K/Akt signaling pathway that involves in the regulation of pressure-dependent myogenic cerebral arterial constriction.

  18. CT Perfusion and MR Perfusion Weighted Imaging in Evaluating the Effect of Vascular Reconstruction on Short-term Cerebral Blood Flow in Patients with Moyamoya Disease%CT灌注与MR灌注加权成像评价烟雾病血管重建术对烟雾病患者短期脑血流的影响

    Institute of Scientific and Technical Information of China (English)

    崔若棣; 易明岗

    2015-01-01

    Objective To study CT perfusion (CTP) and MR perfusion (PWI) weighted imaging in evaluating the effect of vascular reconstruction on short-term cerebral blood flow in patients with moyamoya disease.Methods 47 patients with unilateral vascular reconstruction confirmed by DSA in the hospital were selected as the research objects and all received vascular reconstruction. All the patients received CTP and PWI examination before and after operation to obtain parameters, such as cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT) and time to peak (TTP). The preoperative and postoperative distribution of cerebral middle artery (MCA) and ipsilateral cerebellar perfusion parameters in control part (rCBF, rCBV, rMTT and rTTP) were compared as well as the differences in preoperative and postoperative relative value of CTP and PWI perfusion parameters.Results Postoperative CT perfusion image showed that CBF, CBV, MTT and TTP in the right distribution area of MCA significantly changed, compared with those before operation. Postoperative PWI perfusion image showed that CBF, CBV, MTT and TTP significantly significantly changed, compared with those before operation. After operation, rCBF and rCBV values in the distribution area of operation side MCA and the control ares were significantly higher than those before operation (P<0.05) while rMTT and rTTP were significantly lower than those before operation (P<0.05).Conclusion Both of CT perfusion and MR perfusion weighted imaging are the effective observation methods to observe the changes of cerebral blood flow in patients with moyamoya disease, which can be used in clinic.%目的:研究CT灌注(CTP)与MR灌注(PWI)加权成像评价烟雾病血管重建术对烟雾病患者短期脑血流的影响。方法选取我院47例经DSA证实的单侧血管重建术患者为研究对象,均行血管重建术治疗,术前术后接受CTP、PWI检查,获得脑血容量(CBV)、脑血流量(CBF)、平均通

  19. Perfusion MRI derived indices of microvascular shunting and flow control correlate with tumor grade and outcome in patients with cerebral glioma.

    Directory of Open Access Journals (Sweden)

    Anna Tietze

    Full Text Available Deficient microvascular blood flow control is thought to cause tumor hypoxia and increase resistance to therapy. In glioma patients, we tested whether perfusion-weighted MRI (PWI based indices of microvascular flow control provide more information on tumor grade and patient outcome than does the established PWI angiogenesis marker, cerebral blood volume (CBV.Seventy-two glioma patients (sixty high-grade, twelve low-grade gliomas were included. Capillary transit time heterogeneity (CTH and the coefficient of variation (COV, its ratio to blood mean transit time, provide indices of microvascular flow control and the extent to which oxygen can be extracted by tumor tissue. The ability of these parameters and CBV to differentiate tumor grade were assessed by receiver operating characteristic curves and logistic regression. Their ability to predict time to progression and overall survival was examined by the Cox proportional-hazards regression model, and by survival curves using log-rank tests.The best prediction of grade (AUC = 0.876; p < 0.05 was achieved by combining knowledge of CBV and CTH in the enhancing tumor and peri-focal edema, and patients with glioblastoma multiforme were identified best by CTH (AUC = 0.763; p<0.001. CTH outperformed CBV and COV in predicting time to progression and survival in all gliomas and in a subgroup consisting of only high-grade gliomas.Our study confirms the importance of microvascular flow control in tumor growth by demonstrating that determining CTH improves tumor grading and outcome prediction in glioma patients compared to CBV alone.

  20. CT灌注成像对颅脑创伤病灶周围血流灌注的鉴别意义%The distinguishing meaning of CT perfusion on the blood perfusion of the area of cranio-cerebral trauma focus

    Institute of Scientific and Technical Information of China (English)

    戴君侠; 孙军; 陈茂华

    2015-01-01

    Objective: To explore the distinguishing meaning of CT perfusion (CTP) on the blood perfu-sion condition of the area of cranio-cerebral trauma focus.Methods: CT scanning was used in the patients with different cranio-cerebral trauma. Furthermore, CTP was used to examine those lesions with low-density shadow surrounding, while an analysis of the parameters of mean transit time (MTT), regional cerebral blood flow (rCBF) and regional cerebral blood volume (rCBV), and a comparison of patient prognoses were also conducted. Results: CT scan showed low-density focus of the brain parenchyma around the site of the trauma in 79 cases; CT perfusion parameters showed hypo-perfusion of the brain tissue around the trauma in 42 cases (54.4%), high perfusion in 35 cases (44.3%), while there were no obvious brain tissue perfusion abnormalities in 2 cases. Prog-nosis of low perfusion was poorer.Conclusion: CT examination should apply further CTP in the case of those patients who have been found to display low-density shadow around their cranio-cerebral trauma, in order to help clinicians to better understand the local haemodynamic state of the brain tissue. This has great signiifcance on the diagnosis of focus microcirculation disturbance of cranio-cerebral trauma.%目的:探讨CT灌注成像(CTP)对颅脑创伤病灶周围组织血流灌注情况的鉴别意义。方法:对头颅CT扫描提示有脑挫裂伤病灶,且病灶周围存在低密度影的颅脑创伤患者79例行CTP检查,将每例的平均通过时间(MTT)、局部脑血流量(rCBF)、局部脑血容量(rCBV)等参数值和格拉斯哥预后评分(GOS)进行比较分析。结果:CTP显示创伤周围脑组织低灌注42例(占54.4%),高灌注35例(占44.3%),2例未见明显脑组织灌注异常。低灌注(rCRF、rCBV降低,MTT延长)者预后较差。结论:对CT检查发现颅脑创伤病灶周围低密度影患者进一步行CTP检查,能使临床医师了解脑

  1. Comparison of the ocular perfusion pressure fluctuation between medically controlled and operated eyes with glaucoma

    Directory of Open Access Journals (Sweden)

    Carolina Engelbrecht

    2014-04-01

    Full Text Available Purpose: To compare the fluctuation of the OPP between eyes treated with glaucoma medication and eyes with a functioning filtering bleb. Design: cross-sectional controlled paired-eye design. Methods: Fourteen patients with POAG with one eye operated on (trabeculectomy and the fellow eye treated with medication enrolled the study. Blood pressure and intraocular pressure were measured at 7 a.m., 1 p.m., and 7 p.m. Systolic, diastolic and mean OPP were calculated for the three time points and the fluctuation (range between the highest and the lowest values compared between the eyes. Results: Mean values of the mean OPP fluctuation were 7.2 ± 3.9 mmHg and 8.5 ± 4.0 mmHg, for operated eyes and medically treated eyes, respectively (P = 0.149; mean systolic OPP fluctuation was 20.7 ± 11.2 mmHg for operated eyes and 21.2 ± 11.7 mmHg for medically treated eyes (P = 0.478; the mean diastolic OPP fluctuation was 8.4 ± 4.4 mmHg for operated eyes and 10.5 ± 5.4 mmHg for medically treated eyes (P= 0.085. Conclusion: In this small cohort of patients with POAG the mean, systolic and diastolic OPP fluctuation did not differ between the operated eyes and medically treated ones. Financial disclosure: none.

  2. Plasma-mediated vascular dysfunction in the reduced uterine perfusion pressure model of preeclampsia: a microvascular characterization.

    LENUS (Irish Health Repository)

    Walsh, Sarah K

    2012-01-31

    Preeclampsia is associated with widespread maternal vascular dysfunction, which is thought to be mediated by circulating factor(s). The aim of the study was to characterize vascular function in the reduced uterine perfusion pressure (RUPP) rat model of preeclampsia and to investigate the role of plasma factors in mediating any observed changes in vascular reactivity. Mean arterial blood pressure and vascular function were measured in RUPP and control rats. Mesenteric vessels from both virgin and pregnant rats were exposed for 1 hour or overnight to plasma from both RUPP and control rats and their vascular function assessed. RUPP rats were characterized by severe hypertension, restricted fetal growth, and reduced placental weight (P<0.001). Vasorelaxation was impaired in resistance vessels from RUPP compared with control rats (acetylcholine: R(max) 70+\\/-3 versus 92+\\/-1 [NP] and 93+\\/-3% [sham], P<0.01; bradykinin: 40+\\/-2 versus 62+\\/-2 [NP] and 59+\\/-4% [sham], P<0.001). Incubation of vessels from pregnant (but not virgin) animals with RUPP plasma overnight resulted in an attenuation of vasorelaxant responses (acetylcholine: 63+\\/-7 versus 86+\\/-2%, P<0.05; bradykinin: 35+\\/-5 versus 55+\\/-6%, P<0.001). The residual relaxant response in RUPP plasma-treated vessels was not further attenuated after treatment with N(omega)-nitro-l-arginine methyl ester (acetylcholine: 57+\\/-7 versus 63+\\/-7%, ns; bradykinin: 37+\\/-5 versus 35+\\/-5%, ns). The RUPP rat model is characterized by an impaired response to vasodilators which may be attributable to one or more circulating factors. This plasma-mediated endothelial dysfunction appears to be a pregnancy-dependent effect. Furthermore, nitric oxide-mediated vasorelaxation appears to be absent in RUPP plasma-treated vessels.

  3. Contribution of perfusion pressure to vascular resistance response during head-up tilt

    Science.gov (United States)

    Imadojemu, V. A.; Lott, M. E.; Gleeson, K.; Hogeman, C. S.; Ray, C. A.; Sinoway, L. I.

    2001-01-01

    We measured brachial and femoral artery flow velocity in eight subjects and peroneal and median muscle sympathetic nerve activity (MSNA) in five subjects during tilt testing to 40 degrees. Tilt caused similar increases in MSNA in the peroneal and median nerves. Tilt caused a fall in femoral artery flow velocity, whereas no changes in flow velocity were seen in the brachial artery. Moreover, with tilt, the increase in the vascular resistance employed (blood pressure/flow velocity) was greater and more sustained in the leg than in the arm. The ratio of the percent increase in vascular resistance in leg to arm was 2.5:1. We suggest that the greater vascular resistance effects in the leg were due to an interaction between sympathetic nerve activity and the myogenic response.

  4. Application of stressed cerebral blood flow perfusion imaging in cerebrovascular disease%负荷试验脑血流灌注显像在脑血管疾病中的应用

    Institute of Scientific and Technical Information of China (English)

    尹立杰; 刘杰; 金超岭; 王荣福

    2016-01-01

    The incidence of ischemic cerebrovascular disease is currently high. The disease can be diagnosed and treated by numerous methods, including transcranial doppler, CT angiography, MRI, digital subtraction angiography and cerebral blood flow perfusion imaging of resting and stress states. In these methods, the clinical application of stressed cerebral blood flow perfusion imaging is very wide and includes vertical load tests, CO2 inhalation load tests, acetazolamide stress tests, dipyridamole stress tests, and adenosine stress tests. Stressed cerebral blood flow perfusion imaging can provide an objective basis for the early diagnosis, curative effect evaluation, prognostic estimation, and evaluation of brain reserve function.%目前,缺血性脑血管病发病率较高,对其诊治方法很多,包括经颅多普勒超声、 CT血管造影、 MRI、数字减影血管造影和静息及负荷试验脑血流灌注显像等。其中,负荷试验脑血流灌注显像包括直立负荷试验、 CO2吸入负荷试验、乙酰唑胺负荷试验、潘生丁负荷试验、腺苷负荷试验等,其临床应用非常广泛,为临床早期诊断、疗效评价、预后以及脑血流储备功能的评估提供了客观依据。

  5. Fair灌注成像在一侧大脑中动脉狭窄或闭塞中的应用%Fair for evaluation of middle cerebral artery stenosis or occlusion in brian tissue perfusion imaging

    Institute of Scientific and Technical Information of China (English)

    刘玉涛; 李淑明; 阮骥

    2011-01-01

    目的 探讨Fair灌注成像对大脑中动脉狭窄或闭塞中灌注信息的诊断价值,为指导临床提供依据.方法 20例临床TIA患者或怀疑大脑血管的狭窄或闭塞患者,行常规MRI,DWI,MRA,Fair和DSC检查,确定病变范围,定量评价Fair与DSC的rCBF差异.结果 Fair CBF图显示患侧与健侧灌注程度改变对比t=4.46,P<0.05,有差异;Fair 的rCBF为0.84±0.52,DSC的rCBF为0.79±0.31,二者对比:t=0.705,P >0.05,无统计血差异.结论 Fair为无创性脑灌注成像,操作简单,能定量评估的大脑中动脉狭窄或闭塞引起的缺血性脑血管病的灌注信息.%Objective To disscuss diagnostic value of Fair in cerebral artery stenosis or occlusion reperfusion.Methods 20 patients of middle cerebral artery stenosis or occlusion were studied with rountine MRI,DWI,MRA,Fair and DSC examination, Showing the size of lesions were compared, The perfusion difference between Fair and DSC through the rCBF was compared.Results Fair showed the perfusion of abnomality of unilateral and contralateral changes in perfusion , t=4.46, P<0.05, with statistical significance.rCBF of Fair was 0.84±0.52, rCBF of DSC was 0.79±0.31, Comparison of DSC and Fair perfusionmethod showed no difference (t=0.705,P>0.05).Conclusion Fair, need no contrast injection of invasive operation, is convenient and useful method in assessing cerebral perfusion information of middle cerebral artery stenosis or occlusion.

  6. [Effects of solcoseryl on the cerebral blood flow, intracranial pressure, systemic blood pressure and EEG in acute intracranial hypertensive cats (author's transl)].

    Science.gov (United States)

    Kubota, S; Asakura, T; Kitamura, K

    1976-02-01

    The experiment was performed on 86 cases under intraperitoneal pentobarbital anesthesia. One balloon was placed in the extradural space of right frontal region, and the other balloon was placed in the left extradural space and the intracranial pressure was measured. A needle was stereotaxically inserted into the subcortical area in order to measure the cerebral blood flow. Systemic blood pressure was recorded by inserting a catheter into the femoral artery, and electrocorticogram was also recorded. An expanding intracranial lesion was made by inflating the extradural balloon with physiological saline. The animals were arbitrarily divided into two groups.: 1) light or moderate groups which intracranial pressure before the injection of drug was below 400 mmH2O. 2) severe groups above 400 mmH2O. After the maintenance of the pressure, Solcoseryl was infused intravenously. The investigation was focused to observe whether Solcoseryl reveales any potent effect on cerebral blood flow, intracranial pressure, systemic blood pressure and on electroencephalogram in acute intracranial hypertension. Results 1) Intravenous injection of Solcoseryl had the effect of lowering intracranial pressure in the light or moderate and severe groups. Particularly, dose of 80 mg/kg showed the marked effect, though with a rebound phenomenon in the light or moderate groups. Furthermore, the effect was more marked and lasting by drip infusion of Solcoseryl and also by intravenous injection of Solcoseryl after pretreatment with hydrocortisone, and at this time no rebound phenomenon was recognized. 2) Solcoseryl had the effect of increasing the cerebral blood flow accompained with the lowering of intracranial pressure. 3) Systemic blood pressure was transiently lowered by the injection of Solcoseryl 20 mg/kg or 80 mg/kg and recovered immediately. 4) Solcoseryl had no effect on electroencephalogram in the severe groups. Conclusion On the basis of these results, it is rational to conclude that

  7. MELAS综合征患者脑灌注异常的MRI特征%MRI evaluation of cerebral perfusion changes in patients with MELAS syndrome

    Institute of Scientific and Technical Information of China (English)

    谢晟; 齐朝月; 肖江喜; 杨艳玲; 蒋学祥

    2008-01-01

    Objective To detect the changes of cerebral perfusion in patients with MELAs syndrome by using MR perfusion technique.Methods Thirteen patients with MELAS syndrome and 13 controls with normal neurological conditions were scanned with the sequence of flow-sensitive alternating inversion recovery exempting separate T1 measurement(FAIREST).Their rCBF values were obtained in regions of bilateral basilar nuclei and thalami,as well as bilateral temporal lobes and occipital lobes.Regression analysis was carried out to determine the effect of location and side on the measurement of rCBF in controls.One-way ANOVA was conducted to compare rCBF values among the control group.the lesion ROIs and normal ROIs of the MELAS syndrome group.Results The values of rCBF were 0.83±0.23,1.17±0.30.0.93±0.28,and 1.11±0.25 for the left basilar ganglia,thalamus,temporal lobe,and occipital lobe respectively,while they were 0.77±0.15,1.03±0.34,1.06±0.23,and 1.09±0.23 for the right basilar ganglia,thalamus,temporal lobe.and occipital lobe respectively.Regression analysis revealed no effect of location and side on the rCBF (P>0.05).The rCBF value for control group was 1.00±0.28,while it was 1.01±0.31 for the normal ROIs and 1.95±0.43 for the lesion ROIs in the MELAS syndrome group(F=54.99.P<0.01).The rCBF of the lesion ROIs in the MELAS syndrome group was significantly higher than the normal ROIs and the control group.Conclusion CBF maps can reveal changes of cerebral blood flow in patients with ietal MELAS,which suggests increased perfusion in the stroke-like lesions.%目的 探讨MELAS综合征患者的MR脑血流灌注异常特征.方法 对13例确诊的MELAS综合征患者和13名对照组受试者行流速敏感交替反转恢复免除独立T1测量(FAIREST)序列扫描,通过后处理生成脑血流量(CBF)图,分别测量他们的双侧基底节区、丘脑、颢叶和枕叶的相对脑血流量(rCBF)值,采用多元回归法分析对照组中测量部位和侧别对rCBF

  8. 脑梗死前期磁共振脑灌注成像20例分析%Correlation analysis of magnetic resonance perfusion imaging and its stages of regional cerebral hypoperfusion in pre-infarction period

    Institute of Scientific and Technical Information of China (English)

    曾裕镜

    2008-01-01

    目的 探讨脑梗死前期MR脑灌注成像的表现和分期临床应用价值.方法 采用MR脑灌注成像对20例脑血管病患者的197层脑灌注图像和对照组20例非脑血管病患者的197层脑灌注成像进行分析,计算每层图像的患/健侧比值,并与对照组的正常比值及其范围比较.以非参数统计方法、多元方差分析和两两比较分析病例组和对照组脑灌注血流动力学参数及其分期.结果 病例组和对照组的4个血流动力学参数差异均有统计学意义(P<0.01).TTP(time to peak)和MTT(mean transit time)与发病的相关系数较高,分别为0.482和0.471,rCBV(regional cerebral blood volume)和rCBF(regional cerebral blood flow)较低,且为负值.脑梗死前期分期特征为:Ⅰ期一型TTP稍有延长,Ⅰ期二型MTT显著延长,Ⅱ期一型rCBF明显下降,Ⅱ期二型rCBV下降.结论 MR脑灌注成像可提供脑梗死前期的血流动力学参数变化的信息,并可以对其参数变化进行分期.%Objective To explore clinical value of application to magnetic resonance(MR) perfusion imaging and stages of regional cerebral hypoperfusion in preinfarction period and improve the diagnosis level for pre-infarction period,and prevent or decrease the incidence of cerebral infarction. Methods 20 cases of cerebral ischemia in case group and 20 cases of non-cerebral ischemia in control group were performed with dynamic perfusion. 197 MR images of case group were compared with 197 images of control group,calculating the ratios of illness side to normal for every image at hypoperfusion areas in the regional cerebral isehemia and referring and comparing their range provided by control group with methods of nonparametrie statistics and multivariate analysis of variance and multiple comparison. Results Four parameters of blood flow dynamics between two groups showed a significant difference (P<0.01). Correlation coefficients between time to peak(TTP) and time to peak(MTT) and incidence

  9. Cerebral oxygenation and hyperthermia

    Directory of Open Access Journals (Sweden)

    Anthony Richard Bain

    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.

  10. Phase Synchronization of Pressure-Flow Fluctuations: A measure of cerebral autoregulation dynamics

    CERN Document Server

    Chen, Z; Ivanov, P C; Novák, V; Stanley, H E

    2006-01-01

    We employ a synchronization method to investigate the relationship between the blood flow velocities (BFV) in the middle cerebral arteries (MCA) and beat-to-beat blood pressure (BP) recorded from a finger in healthy and post-stroke subjects during four different physiologic conditions: supine, head-up tilt, hyperventilation and CO$_2$ rebreathing in upright position. To evaluate whether instantaneous BP changes are synchronized with changes in the BFV, we compare dynamical patterns in the instantaneous phases of these signals, obtained from the Hilbert transform, as a function of time. We find that in post-stroke subjects the instantaneous phase increments of BP and BFV exhibit well pronounced patterns that remain stable in time for all four physiologic conditions, while in healthy subjects these patterns are different, less pronounced and more variable. Further, we show that the instantaneous phase increments of BP and BFV are cross-correlated even within a single heartbeat cycle. The maximum correlation str...

  11. A simple model of cerebral blood flow dependence on arterial blood pressure

    CERN Document Server

    Gersten, Alexander

    2011-01-01

    It is shown that the dependence of the cerebral blood flow (CBF) on mean arterial blood pressure (MABP) can be described with a simple model having the following assumptions. Below certain MABP (denoted as MABP1) there are no autoregulatory or feedback mechanisms influencing CBF. Between MABP1 and MABP2 (MABP at which breakthrough accurs) there is a linear (on MABP) dependent feedback with a sloap depending very much on the individual considered. The classical autoregulation model with a plateau in between MABP1 and MABP2 is a particular case of this model. The model describes well the experiments performed on dogs (Harper 1966), for which the individual feedback sloap parameter varied to great extent, indicating the importance of mesurments on individuals against averaged mesurments (or measurments on diffent individuals) which superficially support the classical autoregulation. New effect of decreased CBF, while increasing MABP, was observed.

  12. Effects of special brain area regional cerebral blood flow abnormal perfusion on learning and memory function and its molecular mechanism in rats

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    s To study the effect of special brain area regional cerebral blood flow (rCBF) abnormal perfusion on learning and memory function and its molecular mechanism,64 adult male healthy Spragne-Dawley (SD) rats were randomly divided into two groups,the false operation group (control group) and the operation group (model group).After surgical operation,the operation group undertook bilateral common carotid artery permanent ligation,while the other group did not.Learning and memory function were measured by Y-maze at 4 h,8 h,24 h and 3 d after surgical operation,respectively.The rCBF of the right frontal lobe and hippocampus was also detected by the PerifluxPF model laser Doppler flowmetry,and the expressions of c-fos or c-jun or Bcl-2 and Bax were also measured by immune histochemistry S-P method accordingly.Results showed that the rCBF of the right frontal lobe and hippocampus in the operation group was significantly lower than that in the false operation group (P < 0.05).The learning indexes,error number (EN),day of reach standard and total reaction time (TRT) in the operation group,were significantly higher than that in the false operation group (P< 0.05).However,the initiative evasion rate in the operation group was significantly lower than that in the false operation group.The study also found that the rCBF was relatively more,the indexes (EN,the day of reach standard and TRT) relatively fewer,but the initiative evasion rate and the memory keeping rate were relatively more.The positive expression and the average absorbency of Fos and Jun in the operation group were significantly higher than that in the false operation group (P< 0.05).Furthermore,Bax and Bcl-2 positive cells were all increased over time in the operation group,and the expression ratio of Bax/Bcl-2 in the operation group was significantly higher than that in the false operation group (P<0.01).In conclusion,rCBF decrease can impair the learning and memory function in rats,which may be related to

  13. Preserved regulation of renal perfusion pressure by small and intermediate conductance K-Ca channels in hypertensive mice with or without renal failure

    DEFF Research Database (Denmark)

    Waeckel, L.; Bertin, F.; Clavreul, N.;

    2015-01-01

    The purpose of this study was to assess, in the murine kidney, the mechanisms underlying the endothelium-dependent control of vascular tone and whether or not, in a severe model of hypertension and renal failure, K-Ca channels contribute to its regulation. Wild-type (BL) and double...... hypertensive without kidney disease while ARSL developed severe hypertension and renal failure. In the four groups, methacholine induced biphasic endothelium-dependent responses, a transient decrease in RPP followed by a cyclooxygenase-dependent increase in RPP. In the presence or not of indomethacin......-transgenic female mice expressing human angiotensinogen and renin (AR) genes received either control or a high-salt diet associated to a nitric oxide (NO) synthase inhibitor treatment (BLSL and ARSL). Changes in renal perfusion pressure (RPP) were measured in isolated perfused kidneys. BLSL and AR were moderately...

  14. Ventricular Volume Load Reveals the Mechanoelastic Impact of Communicating Hydrocephalus on Dynamic Cerebral Autoregulation.

    Directory of Open Access Journals (Sweden)

    Christina Haubrich

    Full Text Available Several studies have shown that the progression of communicating hydrocephalus is associated with diminished cerebral perfusion and microangiopathy. If communicating hydrocephalus similarly alters the cerebrospinal fluid circulation and cerebral blood flow, both may be related to intracranial mechanoelastic properties as, for instance, the volume pressure compliance. Twenty-three shunted patients with communicating hydrocephalus underwent intraventricular constant-flow infusion with Hartmann's solution. The monitoring included transcranial Doppler (TCD flow velocities (FV in the middle (MCA and posterior cerebral arteries (PCA, intracranial pressure (ICP, and systemic arterial blood pressure (ABP. The analysis covered cerebral perfusion pressure (CPP, the index of pressure-volume compensatory reserve (RAP, and phase shift angles between Mayer waves (3 to 9 cpm in ABP and MCA-FV or PCA-FV. Due to intraventricular infusion, the pressure-volume reserve was exhausted (RAP 0.84+/-0.1 and ICP was increased from baseline 11.5+/-5.6 to plateau levels of 20.7+/-6.4 mmHg. The ratio dRAP/dICP distinguished patients with large 0.1+/-0.01, medium 0.05+/-0.02, and small 0.02+/-0.01 intracranial volume compliances. Both M wave phase shift angles (r = 0.64; p<0.01 and CPP (r = 0.36; p<0.05 displayed a gradual decline with decreasing dRAP/dICP gradients. This study showed that in communicating hydrocephalus, CPP and dynamic cerebral autoregulation in particular, depend on the volume-pressure compliance. The results suggested that the alteration of mechanoelastic characteristics contributes to a reduced cerebral perfusion and a loss of autonomy of cerebral blood flow regulation. Results warrant a prospective TCD follow-up to verify whether the alteration of dynamic cerebral autoregulation may indicate a progression of communicating hydrocephalus.

  15. Cerebral Blood Flow, Heart Rate, and Blood Pressure Patterns during the Tilt Test in Common Orthostatic Syndromes

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    Peter Novak

    2016-01-01

    Full Text Available Objective. The head-up tilt test is widely used for evaluation of orthostatic intolerance. Although orthostatic symptoms usually reflect cerebral hypoperfusion, the cerebral blood flow velocity (CBFv profile in orthostatic syndromes is not well described. This study evaluated CBFv and cardiovascular patterns associated with the tilt test in common orthostatic syndromes. Methods. This retrospective study analyzed the tilt test of patients with history of orthostatic intolerance. The following signals were recorded: ECG, blood pressure, CBFv using transcranial Doppler, respiratory signals, and end tidal CO2. Results. Data from 744 patients were analyzed. Characteristic pattern associated with a particular orthostatic syndrome can be grouped into abnormalities predominantly affecting blood pressure (orthostatic hypotension, orthostatic hypertension syndrome, vasomotor oscillations, and neurally mediated syncope—cardioinhibitory, vasodepressor, and mixed, cerebral blood flow (orthostatic hypoperfusion syndrome, primary cerebral autoregulatory failure, and heart rate (tachycardia syndromes: postural tachycardia syndrome, paroxysmal sinus tachycardia, and inappropriate sinus tachycardia. Psychogenic pseudosyncope is associated with stable CBFv. Conclusions. The tilt test is useful add-on in diagnosis of several orthostatic syndromes. However diagnostic criteria for several syndromes had to be modified to allow unambiguous pattern classification. CBFv monitoring in addition to blood pressure and heart rate may increase diagnostic yield of the tilt test.

  16. Cerebral Blood Flow, Heart Rate, and Blood Pressure Patterns during the Tilt Test in Common Orthostatic Syndromes

    Science.gov (United States)

    2016-01-01

    Objective. The head-up tilt test is widely used for evaluation of orthostatic intolerance. Although orthostatic symptoms usually reflect cerebral hypoperfusion, the cerebral blood flow velocity (CBFv) profile in orthostatic syndromes is not well described. This study evaluated CBFv and cardiovascular patterns associated with the tilt test in common orthostatic syndromes. Methods. This retrospective study analyzed the tilt test of patients with history of orthostatic intolerance. The following signals were recorded: ECG, blood pressure, CBFv using transcranial Doppler, respiratory signals, and end tidal CO2. Results. Data from 744 patients were analyzed. Characteristic pattern associated with a particular orthostatic syndrome can be grouped into abnormalities predominantly affecting blood pressure (orthostatic hypotension, orthostatic hypertension syndrome, vasomotor oscillations, and neurally mediated syncope—cardioinhibitory, vasodepressor, and mixed), cerebral blood flow (orthostatic hypoperfusion syndrome, primary cerebral autoregulatory failure), and heart rate (tachycardia syndromes: postural tachycardia syndrome, paroxysmal sinus tachycardia, and inappropriate sinus tachycardia). Psychogenic pseudosyncope is associated with stable CBFv. Conclusions. The tilt test is useful add-on in diagnosis of several orthostatic syndromes. However diagnostic criteria for several syndromes had to be modified to allow unambiguous pattern classification. CBFv monitoring in addition to blood pressure and heart rate may increase diagnostic yield of the tilt test. PMID:27525257

  17. Voxel-based analysis of Tc-99 m ECD brain perfusion SPECT in patients with normal pressure hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Bora [Department of Neurology, College of Medicine, Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Yang, Dong-Won [Department of Neurology, College of Medicine, Catholic University of Korea, Seoul 137-701 (Korea, Republic of)], E-mail: neuroman@catholic.ac.kr; Shim, Yong-Soo; Chung, Sung-Woo [Department of Neurology, College of Medicine, Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Ahn, Kook-Jin; O, Joo-Hyun; Kim, Sung-Hoon; Sohn, Hyung-Sun; Chung, Soo-Kyo [Department of Radiology, College of Medicine, Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Chung, Yong-An [Department of Radiology, College of Medicine, Catholic University of Korea, Seoul 137-701 (Korea, Republic of); East-West Research Institute of Translational Medicine (EWTM), Incheon St. Mary' s Hospital, Incheon 403-720 (Korea, Republic of)], E-mail: nm@catholic.ac.kr

    2009-07-15

    Idiopathic normal pressure hydrocephalus (iNPH) is a reversible dementia characterized by gait disturbance, incontinence and dementia. This study investigates the neuropsychological characteristics and changes of regional cerebral blood flow (rCBF) in patients with iNPH. Ten patients who met the criteria of probable iNPH and 13 normal control subjects were evaluated. The general cognitive function and detailed neuropsychological functions were measured by K-MMSE and comprehensive neuropsychological battery. Tc-99m-ethyl cysteinate dimmer (Tc-99m-ECD) single photon emission computed tomography (SPECT) was performed to measure the rCBF and statistical parametric mapping (SPM) and statistical probabilistic brain anatomic map (SPAM) was applied to the objective analysis of SPECT data. On the neuropsychological examination, all the patients showed abnormality in memory, psychomotor speed and frontal executive function. SPM analysis of SPECT images revealed that rCBF in bilateral thalami, right prefrontal area, bilateral anterior and posterior cingulate gyri, right caudate nucleus, and left parahippocampal gyrus was significantly decreased in patients with iNPH compared to normal controls (uncorrected P<0.005). In SPAM analysis, rCBF reduction was observed in bilateral prefrontal area, anterior, posterior cingulate gyri and caudate nuclei. We have found that rCBF changes occurred predominantly in prefrontal and subcortical areas, the changes were associated with frontal subcortical circuit, and the affected frontal subcortical circuit may contribute to the cognitive decline seen in the iNPH patients. The reduction of rCBF and clinical cognitive impairment are closely connected in patients with iNPH.

  18. Measurements of diagnostic examination performance and correlation analysis using microvascular leakage, cerebral blood volume, and blood flow derived from 3T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in glial tumor grading

    Energy Technology Data Exchange (ETDEWEB)

    Server, Andres; Nakstad, Per H. [Oslo University Hospital-Ullevaal, Section of Neuroradiology, Department of Radiology and Nuclear Medicine, Oslo (Norway); University of Oslo, Oslo (Norway); Graff, Bjoern A. [Oslo University Hospital-Ullevaal, Department of Radiology and Nuclear Medicine, Oslo (Norway); Orheim, Tone E.D.; Gadmar, Oeystein B. [Oslo University Hospital, Interventional Centre, Oslo (Norway); Schellhorn, Till [Oslo University Hospital-Ullevaal, Section of Neuroradiology, Department of Radiology and Nuclear Medicine, Oslo (Norway); Josefsen, Roger [Oslo University Hospital-Ullevaal, Department of Neurosurgery, Oslo (Norway)

    2011-06-15

    To assess the diagnostic accuracy of microvascular leakage (MVL), cerebral blood volume (CBV) and blood flow (CBF) values derived from dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MR imaging) for grading of cerebral glial tumors, and to estimate the correlation between vascular permeability/perfusion parameters and tumor grades. A prospective study of 79 patients with cerebral glial tumors underwent DSC-MR imaging. Normalized relative CBV (rCBV) and relative CBF (rCBF) from tumoral (rCBVt and rCBFt), peri-enhancing region (rCBVe and rCBFe), and the value in the tumor divided by the value in the peri-enhancing region (rCBVt/e and rCBFt/e), as well as MVL, expressed as the leakage coefficient K{sub 2} were calculated. Hemodynamic variables and tumor grades were analyzed statistically and with Pearson correlations. Receiver operating characteristic (ROC) curve analyses were also performed for each of the variables. The differences in rCBVt and the maximum MVL (MVL{sub max}) values were statistically significant among all tumor grades. Correlation analysis using Pearson was as follows: rCBVt and tumor grade, r = 0.774; rCBFt and tumor grade, r = 0.417; MVL{sub max} and tumor grade, r = 0.559; MVL{sub max} and rCBVt, r = 0.440; MVL{sub max} and rCBFt, r = 0.192; and rCBVt and rCBFt, r = 0.605. According to ROC analyses for distinguishing tumor grade, rCBVt showed the largest areas under ROC curve (AUC), except for grade III from IV. Both rCBVt and MVL{sub max} showed good discriminative power in distinguishing all tumor grades. rCBVt correlated strongly with tumor grade; the correlation between MVL{sub max} and tumor grade was moderate. (orig.)

  19. Perfusão cerebral retrógrada é método eficaz de proteção cerebral?: resultados imediatos de estudo consecutivo e randomizado

    Directory of Open Access Journals (Sweden)

    FONTES Ronaldo D.

    1999-01-01

    Full Text Available Foram estudados 30 pacientes com diagnóstico de aneurisma ou dissecção de aorta tratados cirurgicamente. O método utilizado consistiu: uso de hipotermia profunda, parada circulatória total, infusão de 0,20 mg/Kg de peso de dexametasona intravenosa e 10 mg/Kg/peso de thiopental, colocação dos pacientes em Trendelemburg a 45 graus durante o período de parada respiratória. Os 30 pacientes foram operados consecutivamente e randomizados em 2 grupos. Grupo I constituído de 15 pacientes, nos quais foi utilizada a perfusão cerebral retrógrada (PCR através da veia cava superior e Grupo II também com 15 pacientes nos quais não foi utilizada PCR. Onze (36,7% pacientes tinham aneurisma da aorta ascendente e arco aórtico, 7 (23,3% tinham dissecção aguda da aorta do tipo I, 6 (20% com dissecção crônica da aorta ascendente e os 6 (20% restantes outros diagnósticos não agrupáveis. Foi realizada análise das seguintes variáveis independentes para mortalidade: idade, sexo, tempo de circulação extracorpórea, tempo de parada circulatória, diagnóstico, complicações prévias, comparando os dois grupos. A mortalidade imediata do Grupo I foi de 4/15 (insuficiência respiratória 26,6% e no Grupo II 3/15 (coma 20,0% - p =1,00. A incidência de complicações neurológicas no Grupo I foi 3/15 (20,0% e no Grupo II, 2/15 (13,3% p = 1,000. A análise estatística utilizando o teste exato de Fisher não demonstrou diferença entre os dois grupos com relação à mortalidade imediata e complicações neurológicas. As causas de óbito foram: insuficiência respiratória em 4 pacientes, alteração neurológica, hiperpotassemia e infarto do miocárdio, respectivamente nos 3 últimos. No presente trabalho, concluímos que a associação de PCR não oferece proteção cerebral mais eficaz que a parada circulatória total associada à hipotermia profunda, para o tempo de isquemia utilizado.

  20. Effects of the New Aldose Reductase Inhibitor Benzofuroxane Derivative BF-5m on High Glucose Induced Prolongation of Cardiac QT Interval and Increase of Coronary Perfusion Pressure

    Directory of Open Access Journals (Sweden)

    C. Di Filippo

    2016-01-01

    Full Text Available This study investigated the effects of the new aldose reductase inhibitor benzofuroxane derivative 5(6-(benzo[d]thiazol-2-ylmethoxybenzofuroxane (BF-5m on the prolongation of cardiac QT interval and increase of coronary perfusion pressure (CPP in isolated, high glucose (33.3 mM D-glucose perfused rat hearts. BF-5m was dissolved in the Krebs solution at a final concentration of 0.01 μM, 0.05 μM, and 0.1 μM. 33.3 mM D-glucose caused a prolongation of the QT interval and increase of CPP up to values of 190 ± 12 ms and 110 ± 8 mmHg with respect to the values of hearts perfused with standard Krebs solution (11.1 mM D-glucose. The QT prolongation was reduced by 10%, 32%, and 41%, respectively, for the concentration of BF-5m 0.01 μM, 0.05 μM, and 0.1 μM. Similarly, the CPP was reduced by 20% for BF-5m 0.05 μM and by 32% for BF-5m 0.1 μM. BF-5m also increased the expression levels of sirtuin 1, MnSOD, eNOS, and FOXO-1, into the heart. The beneficial actions of BF-5m were partly abolished by the pretreatment of the rats with the inhibitor of the sirtuin 1 activity EX527 (10 mg/kg/day/7 days i.p. prior to perfusion of the hearts with high glucose + BF-5m (0.1 μM. Therefore, BF-5m supplies cardioprotection from the high glucose induced QT prolongation and increase of CPP.

  1. 17β Estradiol Modulates Perfusion Pressure and Expression of 5-LOX and CYP450 4A in the Isolated Kidney of Metabolic Syndrome Female Rats

    Directory of Open Access Journals (Sweden)

    A. M. Zúñiga-Muñoz

    2015-01-01

    Full Text Available Prevalence of metabolic syndrome and progression of nephropathy depend on sex. We examined a protective effect of estradiol against nephropathy in metabolic syndrome through the modulation of the arachidonic acid metabolism by activating the 5-lipoxygenase and cytochrome p450 4A pathways. 28 female Wistar rats were divided into four groups of seven animals each: control, intact metabolic syndrome, ovariectomized metabolic syndrome, and metabolic syndrome ovariectomized plus estradiol. Blood pressure, body weight, body fat, triglycerides, insulin, HOMA-index, albuminuria, and TNF-α were increased in ovariectomized metabolic syndrome rats (p<0.001. The perfusion pressure in isolated kidneys of ovariectomized metabolic syndrome rats in presence of 4 μg of arachidonic acid was increased. The inhibitors of the arachidonic acid metabolism Baicalein, Miconazole, and Indomethacin in these rats decreased the perfusion pressure by 57.62%, 99.83%, and 108.5%, respectively and they decreased creatinine clearance and the arachidonic acid percentage. Phospholipase A2 expression in the kidney of ovariectomized metabolic syndrome rats was not modified. 5-lipoxygenase was increased in metabolic syndrome ovariectomized rats while cytochrome p450 4A was decreased. In conclusion, the loss of estradiol increases renal damage while the treatment with estradiol benefits renal function by modulating arachidonic acid metabolism through the 5-lipoxygenase and cytochrome p450 4A pathways.

  2. 64层CT脑灌注联合CTA在早期缺血性脑血管病中的应用%Application of perfusion and CTA by 64 slice CT in early ischemia cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    李培秀; 都日娜; 丁俊丽; 张强

    2011-01-01

    目的 探讨64层螺旋CT脑灌注加CT血管成像技术在早期脑梗死的应用价值.方法 分析总结108例发病在6h内临床可疑脑梗死,其中105例进行CT平扫、CT脑灌注和CTA,部分复查CTP的住院患者资料,并对影像资料做统计学分析.结果 CT平扫7例脑实质密度轻微减低、脑沟变浅(6.6%),CT脑灌注83例显示与临床症状对应区域血流灌注异常(79.1%),与对侧比较CBF下降、CBV下降或正常、TTP延长.22例CT灌注未见异常(20.9%).CT血管成像显示53支动脉(39例)有不同密度斑块及管腔狭窄,3例检查未成功.结论 CT脑灌注加CTA成像技术可以快速、准确确定缺血半暗带及病变血管,对早期缺血性脑血管脑的诊断和指导治疗有重要的临床应用价值.%Objective To discuss the application of cerebral perfusion and CT blood vessel imaging technique by 64-slice CT in diagnosis of cerebral infarction in its early phase. Methods To analyze and summarize the data of 108 patients who were suspected of the ischemic infarction in 6 hours. 105 among the patients were examined by CT scanning, CT perfusion and CTA. Some of those patients needed the examination by CTP again. All data were analyzed statistically. Results CT scanning showed a slight reduction in the density of brain parenchyma in 7 cases, with brain shallow groove(6. 6%) and CT perfusion showed blood perfusion abnormal corresponding to clinical symptom region in 83 cases (79. 1%). Compared with the contra-lateral, CBF were decreased and CBV were decreased or normal while TTP was extend. 22 cases of CT perfusion showed regular!20. 9%). CT blood vessel imaging showed that 53 arteries of 39 patients had spots and the pipes were narrow. 3 cases were not successful. Conclusion Cerebral perfusion and CTA imaging technique by CT can quickly and exactly definite ischemia and pathology blood vessel, which is of great clinical importance for diagnosing and curing brain ischemia in its early phase.

  3. In Acute Stroke, Can CT Perfusion-Derived Cerebral Blood Volume Maps Substitute for Diffusion-Weighted Imaging in Identifying the Ischemic Core?

    Directory of Open Access Journals (Sweden)

    William A Copen

    Full Text Available In the treatment of patients with suspected acute ischemic stroke, increasing evidence suggests the importance of measuring the volume of the irreversibly injured "ischemic core." The gold standard method for doing this in the clinical setting is diffusion-weighted magnetic resonance imaging (DWI, but many authors suggest that maps of regional cerebral blood volume (CBV derived from computed tomography perfusion imaging (CTP can substitute for DWI. We sought to determine whether DWI and CTP-derived CBV maps are equivalent in measuring core volume.58 patients with suspected stroke underwent CTP and DWI within 6 hours of symptom onset. We measured low-CBV lesion volumes using three methods: "objective absolute," i.e. the volume of tissue with CBV below each of six published absolute thresholds (0.9-2.5 mL/100 g, "objective relative," whose six thresholds (51%-60% were fractions of mean contralateral CBV, and "subjective," in which two radiologists (R1, R2 outlined lesions subjectively. We assessed the sensitivity and specificity of each method, threshold, and radiologist in detecting infarction, and the degree to which each over- or underestimated the DWI core volume. Additionally, in the subset of 32 patients for whom follow-up CT or MRI was available, we measured the proportion of CBV- or DWI-defined core lesions that exceeded the follow-up infarct volume, and the maximum amount by which this occurred.DWI was positive in 72% (42/58 of patients. CBV maps' sensitivity/specificity in identifying DWI-positive patients were 100%/0% for both objective methods with all thresholds, 43%/94% for R1, and 83%/44% for R2. Mean core overestimation was 156-699 mL for objective absolute thresholds, and 127-200 mL for objective relative thresholds. For R1 and R2, respectively, mean±SD subjective overestimation were -11±26 mL and -11±23 mL, but subjective volumes differed from DWI volumes by up to 117 and 124 mL in individual patients. Inter-rater agreement

  4. An alternative approach to estimation of the brain perfusion index for measurement of cerebral blood flow using technetium-99m compounds

    Energy Technology Data Exchange (ETDEWEB)

    Murase, Kenya; Mochizuki, Teruhito; Ikezoe, Junpei [Dept. of Radiology, Ehime University School of Medicine, Shitsukawa, Shigenobu-cho (Japan); Inoue, Takeshi; Fujioka, Hiroyoshi; Ishimaru, Yoshihiro; Akamune, Akihisa [Dept. of Radiology, Matsuyama Shimin Hospital, Ohte-machi, Matsuyama, Ehime (Japan); Yamamoto, Yuji [Department of Neurosurgery, Matsuyama Shimin Hospital, Ohte-machi, Matsuyama, Ehime (Japan)

    1999-10-01

    Cerebral blood flow (CBF) has been quantified non-invasively using the brain perfusion index (BPI) determined from radionuclide angiographic data generated by technetium-99m hexamethylpropylene amine oxime ({sup 99m}Tc-HMPAO) or technetium-99m ethyl cysteinate dimer ({sup 99m}Tc-ECD). The BPI is generally calculated using graphical analysis (GA). In the present study, BPI was measured using spectral analysis (SA), and its usefulness evaluated in comparison with GA. The BPI was calculated from the sum of spectral data obtained by SA. We applied this method to radionuclide angiographic data collected from the bilateral brain hemispheres of 20 patients with various brain diseases using {sup 99m}Tc-HMPAO and from those of 20 patients using {sup 99m}Tc-ECD. We also measured BPI using GA. The BPI values obtained by SA (BPI{sup S}) (x) and by GA (BPI{sup G}) (y) correlated closely (y=0.708x+0.038, r=0.945 for {sup 99m}Tc-HMPAO and y=0.559x+0.093, r=0.931 for {sup 99m}Tc-ECD). However, the BPI{sup G} values were underestimated by 22.9%{+-}6.6% (mean{+-}SD) for {sup 99m}Tc-HMPAO and by 27.9%{+-}7.5% for {sup 99m}Tc-ECD as compared with the BPI{sup S} values. The extent of underestimation tended to increase with increasing BPI{sup S} values. These findings were considered to be a result of the BPI{sup G} values being affected by the first-pass extraction fraction of the tracer. We also compared the BPI{sup S} and BPI{sup G} values with those of CBF measured using N-isopropyl-p-[{sup 123}I]iodoamphetamine (CBF{sup IMP}) in 16 patients (six for {sup 99m}Tc-HMPAO and ten for {sup 99m}Tc-ECD). Although both BPI{sup S} and BPI{sup G} values correlated significantly with the CBF{sup IMP} values, the correlation coefficient in BPI{sup S} was always better than that in BPI{sup G} (r=0.869 for {sup 99m}Tc-HMPAO and r=0.929 for {sup 99m}Tc-ECD in BPI{sup S}, r=0.629 for {sup 99m}Tc-HMPAO and r=0.856 for {sup 99m}Tc-ECD in BPI{sup G}). These results suggest that SA can provide a more

  5. A 4D CT digital phantom of an individual human brain for perfusion analysis

    NARCIS (Netherlands)

    Manniesing, R.; Brune, C.; Ginneken, B. van; Prokop, M.

    2016-01-01

    Brain perfusion is of key importance to assess brain function. Modern CT scanners can acquire perfusion maps of the cerebral parenchyma in vivo at submillimeter resolution. These perfusion maps give insights into the hemodynamics of the cerebral parenchyma and are critical for example for treatment

  6. The regulating blood pressure in the acute cerebral infarction with heart failure%脑梗死急性期合并心衰血压调控策略

    Institute of Scientific and Technical Information of China (English)

    崔兆文; 陈丽萍; 李惠珍; 赵国珍; 黄素贞; 刘建辉; 郭小飞

    2008-01-01

    Objective The purpose of the study was to investigate the standard and method of regula-ting blood pressure in the acute cerebral infarction with heart failure. Methods 100 patients who suffered from acute cerebral infarction with heart failure(heart function Ⅱ-Ⅳ grade)in 24 hours were divided randomly into Sodium Nitroprusside treatment group and control group. There was no significant difference about ages, blood pressure,neurologic impairment score and heart failure degree of the patients in two groups. Results Control-ling blood pressure of patients with heart function Ⅱ grade was benefit to heart failure ,but the perfusion of cere-bral blood flow was influenced seriously compared with control group. Reasonably controlling blood pressure of patients with heart function Ⅲ-Ⅳ grade could improve heart function,and the perfusion of cerebral blood flow could also be improved compared with control group. Conclusion Reasonably control blood pressure of patients with acute cerebral infarction with heart failure was benefit to heart function, cerebral hemodynamics and nerval function.%目的 探讨脑梗死急性期合并心衰血压调控的标准及方法.方法 收集100例发病在24 h内的急性脑梗死合并心力衰竭(心功能Ⅱ-Ⅳ级)的患者资料,并随机分为硝普钠治疗组和对照组.全部患者在入院时均进行美国国立卫生院神经功能缺损评分、TCD检查.两组患者的发病年龄、血压增高程度、神经功能缺损评分、TCD改变以及心衰程度差异无统计学意义(P>0.05).结果 心功能Ⅱ级患者血压控制对心衰有益,但却严重影响脑血流灌注.与对照组相比脑血流动力学受损明显.心功能Ⅲ-Ⅳ级患者经合理控制血压,心功能改善后脑血流灌注较对照组有明显改善.结论 脑梗死急性期合并心衰合理调控血压,无论对心功能的改善抑或脑血流动力学和神经系统临床症状的好转都是十分有益的.

  7. Assessment of Cerebral Hemodynamics by 64-Row VCT Perfusion Imaging in Patients with Moya-Moya Disease%64排VCT脑灌注成像对烟雾病的血流动力学研究

    Institute of Scientific and Technical Information of China (English)

    谢安明; 丁耀军

    2014-01-01

    Objective To investigate the changes in cerebral hemodynamics (cerebral blood flow volume,blood capacity,mean transit time and time to peak)using 64-row VCT perfusion im-aging,and to provide imaging evidence for clinical intervention.Methods Thirty patients with moya-moya disease aged 13-49 years (average age 33.8 years,14 males,16 females)were recruited in this study.Cerebral perfusion imaging was performed using a GE LightSpeed VCT scanner at a rate of 5 mL/second and a dose of 50 mL.The scan delay time was 5 seconds and scan time was 45 seconds.Post-processing was conducted with Perfusion 4 software to analyze cerebral blood flow volume,blood capacity,mean transit time and time to peak.Results Of the 30 patients,9 had is-chemic type moya-moya disease and 21 had hemorrhagic type moya-moya disease.The 64-row VCT perfusion imaging showed increased regional cerebral blood flow in 3 patients,decreased re-gional cerebral blood flow in 5,increased regional cerebral blood volume in 3,normal cerebral blood volume in 27,shortened mean transit time and time to peak in 3,and prolonged mean transit time and time to peak in 8.Conclusion Most patients with ischemic type moya-moya disease are characterized by regional hypoperfusion,while patients with hemorrhagic type moya-moya disease are characterized by normal or regional hyperperfusion.The mean transit time and time to peakare sensitive indicators of changes in cerebral hemodynamics.%目的:通过对烟雾病患者进行64排VCT脑灌注成像,了解其脑血流动力学变化情况,包括脑血流量、脑血容量、平均通过时间及达峰时间,为临床干预治疗提供影像学依据。方法30例烟雾病患者,男性14例,女性16例,年龄最大为49岁,最小为13岁,平均年龄为33.8岁。利用 GE公司生产的 LightSpeed VCT螺旋扫描机对烟雾病患者进行灌注扫描,速率5 mL·s-1、剂量50 mL、扫描延迟5 s、扫描时间45 s,然后用该公司配备的 Perfu-sion4

  8. Effects of dexamethasone and cox inhibitors on intracranial pressure and cerebral perfusion in the lipopolysaccharide treated rats with hyperammonemia

    DEFF Research Database (Denmark)

    Rohde, Johan; Pedersen, Hans; Bjerring, Peter N

    2015-01-01

    and lipopolysaccharide (LPS) on the brain can be prevented by dexamethasone and cyclooxygenase (COX) inhibitors. METHOD: Fifty-four male Wistar rats, 6 in each group, were divided into the following groups: Saline+ saline; LPS (2 mg/kg)+saline; LPS+indomethacin (10 mg/kg); LPS+diclofenac (10mg/kg); LPS+dexamethasone (2......mg/kg) in experiment A. Experiment-B included the following groups: LPS+NH3 (140 μmol/kg/min)+saline; LPS+NH3+indomethacin; LPS+NH3+diclofenac and LPS+NH3+dexamethasone. ICP was monitored via a catheter placed in cisterna magna and changes in CBF were recorded by laser Doppler flowmetry. RESULTS: LPS...... with and without NH3 induced a similar increase in plasma 6-keto-prostaglandin-F1α (6-keto-PGF1α) concentration together with a concomitant rise in CBF and ICP. Indomethacin and diclofenac prevented the increase in ICP by LPS alone, and with the addition of NH3 the increase in both CBF and ICP, which...

  9. Intensive blood pressure lowering increases cerebral blood flow in older subjects with hypertension.

    Science.gov (United States)

    Tryambake, Dinesh; He, Jiabao; Firbank, Michael J; O'Brien, John T; Blamire, Andrew M; Ford, Gary A

    2013-06-01

    Hypertension is associated with reduced cerebral blood flow (CBF). Intensive (blood pressure (BP) lowering in older people might give greater reduction in cardiovascular risk, but there are concerns that this might produce hypoperfusion which may precipitate falls and possibly stroke. We determined the effect of intensive compared with usual BP lowering on CBF in hypertensive older subjects. Individuals aged >70 years with a history of systolic hypertension on 1 or no BP lowering drugs were recruited from primary care (n=37; age, 75±4 years; systolic BP, >150 mm Hg) and randomized to receive intensive (target BP, treatment. Baseline BP (ambulatory or in clinic) and baseline gray matter CBF were not significantly different between the groups. After treatment, BP was reduced significantly in both groups but fell more in the intensive group (26/17 versus 15/5 mm Hg; Phypertension increases CBF, compared with BP lowering to usual target. These findings suggest hypertension in older people shifts the autoregulatory CBF curve rightward and downward and is reversible with BP lowering.

  10. Regional cerebral blood flow in normal pressure hydrocephalus: diagnostic and prognostic aspects

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, A. (Dept. of Neurology, Sahlgren Hospital, Goeteborg (Sweden)); Bergh, A.C. (Dept. of Clinical Physiology, Sahlgren Hospital, Goeteborg (Sweden)); Bilting, M. (Dept. of Neurosurgery, Sahlgren Hospital, Goeteborg (Sweden)); Aerlig, AA. (Dept. of Radiation Physics, Sahlgren Hospital, Goeteborg (Sweden)); Jacobsson, L. (Dept. of Radiation Physics, Sahlgren Hospital, Goeteborg (Sweden)); Stephensen, H. (Dept. of Neurosurgery, Sahlgren Hospital, Goeteborg (Sweden)); Wikkelsoe, C. (Dept. of Neurology, Sahlgren Hospital, Goeteborg (Sweden))

    1994-02-01

    Relative regional cerebral blood flow (rrCBF) was measured by SPET using [sup 99m]Tc-HMPAO as flow tracer, in 23 patients with normal pressure hydrocephalus (NPH). 1000 MBq [sup 99m]Tc-HMPAO was given intravenously and the rrCBF calculated as regional/cerebellar count level ratios. The patients were examined before and 3-12 months after ventriculoperitoneal shunt surgery. rrCBF was also determined in ten healthy aged matched volunteers who served as controls. The NPH patients had decreased rrCBF in the hippocampal regions and in the frontal and parietal white matter as compared to the controls. The frontal/parietal rrCBF ratio correlated with both psychiatric disability and the preoperative degree of incontinence. Decreased flow in frontal white matter, frontoparietal and hippocampal grey matter and a low frontalparietal grey matter flow ratio preoperatively correlated with improvement in both Mini Mental State score and psychiatric disability after shunt surgery. After shunt surgery the rrCBF increased in the mesencephalon, frontal grey and white matter, parietal white matter and hippocampus. The flow increase in hippocampal regions and frontal white matter correlated with improvement in psychiatric symptomatology. The results of this study regarding the frontal and hippocampal rrCBF patterns, and the clinical correlation, support the hypothesis that CBF changes in these regions are of patohphysiological and prognostic importance in NPH. (orig./MG)

  11. Dynamic cerebral autoregulation to induced blood pressure changes in human experimental and clinical sepsis

    DEFF Research Database (Denmark)

    Berg, Ronan M G; Plovsing, Ronni R; Bailey, Damian M

    2016-01-01

    (Pvolunteers at baseline; Pvolunteers after LPS). The corresponding RoR values increased from 0·46 (0·31-0·49) s(-1) at baseline to 0·58 (0·36-0·74) s(-1) after LPS (Pvolunteers, whereas they were similar to values observed in patients [0·43 (0·36-0·52) s...... shock. In this study, we hypothesized that this pattern of response would be identical during induced changes in blood pressure. Dynamic cerebral autoregulation was assessed in nine healthy volunteers and six septic patients. The healthy volunteers underwent a 4-h intravenous infusion of LPS (total dose......R). This was performed before and after LPS infusion in healthy volunteers, and within 72 h following clinical diagnosis of sepsis in patients. In healthy volunteers, thigh-cuff deflation caused a MAP reduction of 16 (13-20) % at baseline and 18 (16-20) % after LPS, while the MAP reduction was 12 (11-13) % in patients...

  12. 64 row CT cerebral perfusion applied research of brain ischemia%64排CT脑灌注对脑组织缺血程度的应用研究

    Institute of Scientific and Technical Information of China (English)

    刘贯清; 肖新兰; 李晓; 黄小宁; 李五根

    2015-01-01

    Objective Application of 64 row CT cerebral perfusion brain tissue ischemia. Methods 40 cases of clinical diag-nosis of acute cerebral infarction,patients with unilateral lobe brain perfusion CT perfusion showed abnormal,in combination with MRI to determine infarct,according to the cerebral blood flow group,group A (low perfusion group) and group B (infarction group), respectively,evaluation of two groups of cerebral blood flow perfusion parameters and comparison analysis. Results Of 40 cases, 18 cases of group A,CTP anomaly low perfusion of figure is determined by MTT extend approximately 1.28 (R),decreased CBF mild,CBV basic no change Or moderately reduced,only determined by MTT extension was statistically significant (P<0.01);Infarc-tion group,22 cases of group B,infarction area surrounding IP abnormal perfusion is determined by MTT extend approximately 1. 48(R),CBF significantly decreased approximately 0.45(R),CBV moderately reduced,which extended determined by MTT was sta-tistically significant (P<0.001),decrease CBF was statistically significant (P<0.01);Infarction district performance is determined by MTT extend approximately 1.64(R),CBF significantly decreased approximately 0.36(R),significantly lower CBV (approximately 0. 37)R. Which determined by MTT extension was statistically significant (P<0.001),CBF decline was statistically significant(P<0.01). Conclusion Brain tissue hypoperfusion area with the infarction in central and peripheral IP area the perfusion parameters have significant differences,according to the variation of perfusion parameters characteristics can make the image on the degree of is-chemic infarction assessment,when rCBF<0.5,suggesting infarction risk is extremely high,the clinical guidance for early interven-tion treatment.%目的:探讨应用64排CT脑灌注评价脑组织缺血程度。方法40例临床诊断急性脑梗塞,CT灌注显示单侧脑叶灌注异常患者,结合MRI判断梗塞,根据脑血流量进行分组,A

  13. Autoregulation of cerebral blood flow to changes in arterial pressure in mild Alzheimer's disease.

    Science.gov (United States)

    Zazulia, Allyson R; Videen, Tom O; Morris, John C; Powers, William J

    2010-11-01

    Studies in transgenic mice overexpressing amyloid precursor protein (APP) demonstrate impaired autoregulation of cerebral blood flow (CBF) to changes in arterial pressure and suggest that cerebrovascular dysfunction may be critically important in the development of pathological Alzheimer's disease (AD). Given the relevance of such a finding for guiding hypertension treatment in the elderly, we assessed autoregulation in individuals with AD. Twenty persons aged 75±6 years with very mild or mild symptomatic AD (Clinical Dementia Rating 0.5 or 1.0) underwent (15)O-positron emission tomography (PET) CBF measurements before and after mean arterial pressure (MAP) was lowered from 107±13 to 92±9 mm Hg with intravenous nicardipine; (11)C-PIB-PET imaging and magnetic resonance imaging (MRI) were also obtained. There were no significant differences in mean CBF before and after MAP reduction in the bilateral hemispheres (-0.9±5.2 mL per 100 g per minute, P=0.4, 95% confidence interval (CI)=-3.4 to 1.5), cortical borderzones (-1.9±5.0 mL per 100 g per minute, P=0.10, 95% CI=-4.3 to 0.4), regions of T2W-MRI-defined leukoaraiosis (-0.3±4.4 mL per 100 g per minute, P=0.85, 95% CI=-3.3 to 3.9), or regions of peak (11)C-PIB uptake (-2.5±7.7 mL per 100 g per minute, P=0.30, 95% CI=-7.7 to 2.7). The absence of significant change in CBF with a 10 to 15 mm Hg reduction in MAP within the normal autoregulatory range demonstrates that there is neither a generalized nor local defect of autoregulation in AD.

  14. Concentration-dependent effects of cocaine on monoamine-induced constriction of cannulated, pressurized cerebral arteries from fetal sheep.

    Science.gov (United States)

    Schreiber, M D; Madden, J A; Covert, R F; Hershenson, M B; Torgerson, L J

    1995-01-01

    Drugs, such as cocaine, which may alter monoamine neurotransmitter responsiveness, could adversely affect the regulation of cerebral vasculature. Cocaine exhibits at least two mechanisms that may alter vascular responsiveness: synaptic uptake inhibition, which may augment response to stimulation, and Na+ channel inhibition, which may attenuate response. To help elicit the concentration-dependent effects of cocaine, the effects of cocaine on monoamine neurotransmitter responsiveness were studied in vitro on fetal sheep cerebral arteries (120 days gestation). The changes in diameter of segments of cannulated, pressurized fetal sheep cerebral artery were measured with a videomicroscaler system. Cumulative concentration-response curves (10(-10) to 10(-4)M) were generated for two monoamines, norepinephrine and serotonin, alone and in the presence of cocaine (10(-5) or 10(-4)M). Cocaine caused concentration-dependent alteration of response. At 10(-4)M, cocaine attenuated mean maximal norepinephrine-induced vasoconstriction 46.2% (P < 0.05). At 10(-5)M, cocaine increased sensitivity to norepinephrine (log EC50 decreased -6.63 +/- 0.09 to -7.11 +/- 0.03) and to serotonin (log EC50 decreased -7.24 +/- 0.04 to -7.81 +/- 0.09) (P < 0.05). The higher concentration of cocaine (10(-4)M) did not significantly decrease log EC50 norepinephrine. Cocaine (10(-4)M) also attenuated the response to single doses of norepinephrine (10(-6)M) and serotonin (10(-6)M) by 26.5% and 40.0%, respectively (P < or = 0.05). It is concluded that cocaine has concentration-dependent effects on vasoconstriction of the fetal sheep cerebral artery in vitro. This cocaine-induced alteration of cerebral vascular responsiveness to monoamines may be important in the regulation of fetal cerebral blood flow.

  15. Cerebral effects of commonly used vasopressor-inotropes: a study in newborn piglets.

    Directory of Open Access Journals (Sweden)

    Gitte H Hahn

    Full Text Available BACKGROUND: Despite widespread use in sick infants, it is still debated whether vasopressor-inotropes have direct cerebral effects that might affect neurological outcome. We aimed to test direct cerebrovascular effects of three commonly used vasopressor-inotropes (adrenaline, dopamine and noradrenaline by comparing the responses to those of nonpharmacologically induced increases in blood pressure. We also searched for reasons for a mismatch between the response in perfusion and oxygenation. METHODS: Twenty-four piglets had long and short infusions of the three vasopressor-inotropes titrated to raise mean arterial blood pressure (MAP 10 mmHg in random order. Nonpharmacological increases in MAP were induced by inflation of a balloon in the descending aorta. We measured cerebral oxygenation (near-infrared spectroscopy, perfusion (laser-Doppler, oxygen consumption (co-oximetry of arterial and superior sagittal sinus blood, and microvascular heterogeneity (side stream dark field video microscopy. RESULTS: Vasopressor-inotropes increased cerebral oxygenation significantly less (p≤0.01 compared to non-pharmacological MAP increases, whereas perfusion was similar. Furthermore, cerebral total hemoglobin concentration increased significantly less during vasopressor-inotrope infusions (p = 0.001. These physiologic responses were identical between the three vasopressor-inotropes (p>0.05. Furthermore, they induced a mild, although insignificant increase in cerebral metabolism and microvascular heterogeneity (p>0.05. Removal of the scalp tissue did not influence the mismatch (p>0.05. CONCLUSION: We demonstrated a moderate vasopressor-inotrope induced mismatch between cerebral perfusion and oxygenation. Scalp removal did not affect this mismatch, why vasopressor-inotropes appear to have direct cerebral actions. The statistically nonsignificant increases in cerebral metabolism and/or microvascular heterogeneity may explain the mismatch. Alternatively, it

  16. Brain hypoxanthine concentration correlates to lactate/pyruvate ratio but not intracranial pressure in patients with acute liver failure

    DEFF Research Database (Denmark)

    Bjerring, Peter Nissen; Hauerberg, John; Jørgensen, Linda;

    2010-01-01

    The pathogenesis of cerebral edema in acute liver failure is suggested, in in vitro and animal studies, to involve a compromised oxidative metabolism with a decrease in cerebral ATP levels and an increase in purine concentrations. In this study we hypothesize that the cerebral concentrations...... of hypoxanthine, inosine, and lactate/pyruvate (LP) ratio are increased and correlated in patients with acute liver failure. Furthermore, we expect the purines and L/P ratio to correlate with intracranial pressure (ICP) (positively), and cerebral perfusion pressure (CPP) (negatively)....

  17. Diagnostic examination performance by using microvascular leakage, cerebral blood volume, and blood flow derived from 3-T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in the differentiation of glioblastoma multiforme and brain metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Server, Andres; Nakstad, Per H. [Oslo University Hospital-Ullevaal, Section of Neuroradiology, Department of Radiology and Nuclear Medicine, Oslo (Norway); University of Oslo, Oslo (Norway); Orheim, Tone E.D. [Oslo University Hospital, Interventional Centre, Oslo (Norway); Graff, Bjoern A. [Oslo University Hospital-Ullevaal, Department of Radiology and Nuclear Medicine, Oslo (Norway); Josefsen, Roger [Oslo University Hospital-Ullevaal, Department of Neurosurgery, Oslo (Norway); Kumar, Theresa [Oslo University Hospital-Ullevaal, Department of Pathology, Oslo (Norway)

    2011-05-15

    Conventional magnetic resonance (MR) imaging has limited capacity to differentiate between glioblastoma multiforme (GBM) and metastasis. The purposes of this study were: (1) to compare microvascular leakage (MVL), cerebral blood volume (CBV), and blood flow (CBF) in the distinction of metastasis from GBM using dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MRI), and (2) to estimate the diagnostic accuracy of perfusion and permeability MR imaging. A prospective study of 61 patients (40 GBMs and 21 metastases) was performed at 3 T using DSC-MRI. Normalized rCBV and rCBF from tumoral (rCBVt, rCBFt), peri-enhancing region (rCBVe, rCBFe), and by dividing the value in the tumor by the value in the peri-enhancing region (rCBVt/e, rCBFt/e), as well as MVL were calculated. Hemodynamic and histopathologic variables were analyzed statistically and Spearman/Pearson correlations. Receiver operating characteristic curve analysis was performed for each of the variables. The rCBVe, rCBFe, and MVL were significantly greater in GBMs compared with those of metastases. The optimal cutoff value for differentiating GBM from metastasis was 0.80 which implies a sensitivity of 95%, a specificity of 92%, a positive predictive value of 86%, and a negative predictive value of 97% for rCBVe ratio. We found a modest correlation between rCBVt and rCBFt ratios. MVL measurements in GBMs are significantly higher than those in metastases. Statistically, both rCBVe, rCBVt/e and rCBFe, rCBFt/e were useful in differentiating between GBMs and metastases, supporting the hypothesis that perfusion MR imaging can detect infiltration of tumor cells in the peri-enhancing region. (orig.)

  18. Diagnostic Value of Brain Perfusion Imaging with 64 Multi-Detector Spiral CT in Early Cerebral Infarction%64排螺旋 CT 脑灌注成像对早期脑梗死的诊断价值

    Institute of Scientific and Technical Information of China (English)

    奚彬; 盛伟华; 唐建伟; 黄松; 宋黎涛

    2014-01-01

    目的:探讨64排螺旋 CT 脑灌注成像(CT perfusion imaging,CTP)对早期脑梗死的诊断价值。方法:临床拟诊早期脑梗死患者38例,均在症状出现24 h 内行头颅 CT 平扫及 CTP 检查。将脑梗死核心区、缺血半暗带(ischemic penumbra,IP)区与健侧对应区的情况做对比分析。结果:38例患者中,15例头颅 CT 平扫发现可疑脑梗死区,主要位于大脑半球,表现为密度轻度减低、局部脑沟稍变浅等;其余23例患者 CT 平扫未发现异常。38例患者的 CTP 检查均发现灌注异常区,表现为脑梗死区脑血流量(cerebral blood flow,CBF)与脑血容量(cerebral blood volume,CBV)均较健侧对应区明显下降,对比剂平均通过时间(mean transit time,MTT)较健侧对应区缩短,对比剂达峰时间(time to peak,TTP)较健侧对应区明显延长,差异均有统计学意义(P <0.01)。早期脑梗死患者 IP 区与梗死核心区比较,CBF、CBV、MTT 及 TTP 差异均有统计学意义(P <0.01);IP区与健侧对应区比较,CBF、MTT、TTP 差异均有统计学意义(P <0.05、0.01),CBV 差异无统计学意义(P >0.05)。获得随访的18例患者中,经积极溶栓等治疗后梗死区缩小6例,梗死区消失5例,仅表现为梗死区 TTP 和 MTT 延长、CBF 和 CBV 变化不大3例,梗死区无明显变化4例。结论:64排螺旋 CTP 检查可以准确地提示早期脑梗死。%Objective:To explore the diagnostic value of CT perfusion imaging(CTP)with 64 multi-detector spiral CT in early cerebral infarction.Methods:A total of 38 patients with suspected early cerebral infarction underwent plain CT and CTP within 24 h after the onset of related symptoms.The imaging results in infarction core area,ischemic penumbra (IP) and the contralateral normal region were comparatively analyzed.Results:Early cerebral infarction,mainly in cerebral hemispheres, were suspected

  19. Intensive Blood-Pressure Lowering in Patients with Acute Cerebral Hemorrhage.

    Science.gov (United States)

    Qureshi, Adnan I; Palesch, Yuko Y; Barsan, William G; Hanley, Daniel F; Hsu, Chung Y; Martin, Renee L; Moy, Claudia S; Silbergleit, Robert; Steiner, Thorsten; Suarez, Jose I; Toyoda, Kazunori; Wang, Yongjun; Yamamoto, Haruko; Yoon, Byung-Woo

    2016-09-15

    within 7 days after randomization was significantly higher in the intensive-treatment group than in the standard-treatment group (9.0% vs. 4.0%, P=0.002). Conclusions The treatment of participants with intracerebral hemorrhage to achieve a target systolic blood pressure of 110 to 139 mm Hg did not result in a lower rate of death or disability than standard reduction to a target of 140 to 179 mm Hg. (Funded by the National Institute of Neurological Disorders and Stroke and the National Cerebral and Cardiovascular Center; ATACH-2 ClinicalTrials.gov number, NCT01176565 .).

  20. Study on the correlation between clinical aphasia and cerebral blood perfusion after acute cerebral infarction%急性脑梗死后失语症与脑血流灌注的相关性探讨

    Institute of Scientific and Technical Information of China (English)

    胡军; 朱文炳; 谢瑞满; 修雁

    2002-01-01

    Objective The SPECT brain perfusion was performed to explore the correlation between the yielded image data and the clinical characteristics of aphasia.Method The language function assessment of WAB and SPECT blood perfusion imaging were applied to 21 aphasia patients with dominant ischemic stroke.The correlations between the aphasic characteristics and the ROI rCBF of language regions were analyzed.Result The significant correlations were found between the different brain regions and the different language function deficits,and the correlation between temporal lobe and language function deficits was even higher.Conclusion SPECT brain perfusion imaging can show function disorder of language and aphasia probably caused by the destruction of language nervous network.

  1. Aortic arch replacement with a beating heart: a simple method using continuous 3-way perfusion.

    Science.gov (United States)

    Abu-Omar, Y; Ali, J M; Colah, S; Dunning, J J

    2014-01-01

    We describe a simplified 3-way perfusion strategy that could be used in complex aortic procedures, which ensures continuous end-organ perfusion and minimizes the potential risks of cardiac, cerebral and peripheral ischaemic complications.

  2. Is cerebral oxygenation negatively affected by infusion of norepinephrine in healthy subjects?

    DEFF Research Database (Denmark)

    Brassard, P.; Seifert, T.; Secher, Niels H.

    2009-01-01

    BACKGROUND: Vasopressor agents are commonly used to increase mean arterial pressure (MAP) in order to secure a pressure gradient to perfuse vital organs. The influence of norepinephrine on cerebral oxygenation is not clear. The aim of this study was to evaluate the impact of the infusion of norep......BACKGROUND: Vasopressor agents are commonly used to increase mean arterial pressure (MAP) in order to secure a pressure gradient to perfuse vital organs. The influence of norepinephrine on cerebral oxygenation is not clear. The aim of this study was to evaluate the impact of the infusion...... infused at 0.1 microg kg(-1) min(-1) [Sc(O2): 78 (75-94) to 69 (61-83)%; P cm s(-1); P

  3. The phosphodiesterase 5 inhibitor sildenafil has no effect on cerebral blood flow or blood velocity, but nevertheless induces headache in healthy subjects

    DEFF Research Database (Denmark)

    Kruuse, Christina; Thomsen, Lars Lykke; Jacobsen, Torsten Bjørn

    2002-01-01

    , and regional cerebral blood flow in the perfusion area of the middle cerebral artery (rCBFmca) was measured using single photon emission computed tomography and xenon inhalation. Radial and temporal artery diameters were studied using high-frequency ultrasound. Blood pressure and heart rate were recorded......Cyclic nucleotides are important hemodynamic regulators in many tissues. Glyceryl trinitrate markedly dilates large cerebral arteries and increases cGMP. Here, the authors study the effect of sildenafil, a selective inhibitor of cGMP-hydrolyzing phosphodiesterase 5 on cerebral hemodynamics...

  4. Relationship Between Cerebral Oxygenation and Hemodynamic and Oxygen Transport Parameters in Surgery for Acquired Heart Diseases

    Directory of Open Access Journals (Sweden)

    A. I. Lenkin

    2012-01-01

    Full Text Available Objective: to evaluate the relationship between cerebral oxygenation and hemodynamic and oxygen transport parameters in surgical correction of concomitant acquired heart diseases. Subjects and methods. Informed consent was received from 40 patients who required surgery because of concomitant (two or more acquired heart defects. During procedure, perioperative monitoring of oxygen transport and cerebral oxygenation was performed with the aid of PiCCO2 monitor (Pulsion Medical Systems, Germany and a Fore-Sight cerebral oximeter (CASMED, USA. Anesthesia was maintained with propofol and fen-tanyl, by monitoring the depth of anesthesia. Early postoperative intensive therapy was based on the protocol for early targeted correction of hemodynamic disorders. Oxygen transport and cerebral oxygenation parameters were estimated intraopera-tively and within 24 postoperative hours. A statistical analysis including evaluation of Spearman correlations was performed with the aid of SPSS 15.0. Results. During perfusion, there was a relationship between cerebral oximetry values and hemat-ocrit levels, and oxygen partial pressure in the venous blood. Furthermore, a negative correlation between cerebral oximetry values and blood lactate levels was found 30 minutes after initiation of extracorporeal circulation (EC. During the study, there was a positive correlation between cerebral oxygenation and values of cardiac index, central venous saturation, and oxygen delivery index. There was a negative relationship between cerebral oxygenation and extravascular lung water at the beginning of surgery and a correlation between cerebral oximetry values and oxygenation index by the end of the first 24 postoperative hours. Conclusion. The cerebral oxygenation values correlate -with the main determinants of oxygen transport during EC and after cardiac surgical procedures. Cerebral oximetry may be used in early targeted therapy for the surgical correction of acquired combined

  5. 磁共振灌注加权成像在颅脑胶质瘤分级中的价值研究%Value of MR perfusion weighted imaging in differentiating the tumor grade of cerebral gliomas

    Institute of Scientific and Technical Information of China (English)

    李伟; 龙晚生; 罗学毛; 何义改; 兰勇; 蔡小琴

    2011-01-01

    目的 探讨相对脑血容积(rCBV)、相对脑血流量(rCBF)和相对平均通过时间(rMTT)在鉴别颅脑胶质瘤病理分级中的价值.方法 对病理证实为颅脑胶质瘤的患者(Ⅱ级胶质瘤9例,Ⅲ级胶质瘤11例,Ⅳ级胶质瘤14例)行MR灌注加权成像及常规MRI检查.由灌注加权成像数据获取脑血容积(CBV)图、脑血流量(CBF)图和平均通过时间(MTT)图,计算出rCBV、rCBF和rMTT值.结果 Ⅱ级胶质瘤的rCBV、rCBF和rMTT值分别为2.68±1.37、2.52±1.29和1.02±0.30,Ⅲ级胶质瘤的rCBV、rCBF和rMTT值分别为4.99±2.34、4.77±1.97和1.07±0.15,Ⅳ级胶质瘤的rCBV、rCBF和rMTT值分别为6.69±1.88、6.97±1.73和1.08±0.22,各组间rCBV和rCBF值比较差异有统计学意义(P0.05).结论 MR灌注加权成像能有效地在术前评价颅脑胶质瘤的病理级别,rCBV值结合rCBF值可以更好地对颅脑胶质瘤进行病理分级.%Objective To explore the value of relative cerebral blood volume(rCBV), relative cerebral blood flow(rCBF) and relative mean through time(rMTT) in differentiating the tumor grade of cerebral gliomas. Methods This study involved 34 patients (9 cases of grade Ⅱ,11 cases of grade Ⅲ,14 cases of grade Ⅳ) which were identified as gliomas proved by histopathologic. MR perfusion weighted imaging and conventional MR imaging were underwent on them preoperatively. The perfusion weighted imaging datas were deconvoluted to get a color map of CBV, CBF and MTT. The value of rCBV, rCBF and rMTT of each lesion were calculated and correlated with histopathologic grading of gliomas. Results The value of rCBV, rCBF and rMTT of grade Ⅱ,grade Ⅲ,grade Ⅳ gliomas was (2.68±1.37, 4.99±2.34,6.69±1.88), (2.52±1.29,4.77±1.97,6.97±1.73) and (1.02±0.30,1.07±0.15,1.08±0.22), respectively. The value of rCBV and rCBF had statistically difference in each groups (P0.05).Conclusions MR perfusion weighted imaging is useful in the preoperative assessment of the histopathologic grade

  6. Skin perfusion pressure measured with a photo sensor in an air-filled plastic balloon: validity and reproducibility on the lower leg in normal subjects and patients suspected of obliterative arterial disease

    DEFF Research Database (Denmark)

    Nielsen, Steen Levin; Nielsen, Anne Lerberg; Vind, Susanne Haase

    2011-01-01

    An inflatable small plastic bag including a photo sensor was constructed for measurement of skin perfusion pressure avoiding the rim of the photo sensor over bony and tendineous surfaces of the tibia below the knee, at the ankle, and on the dorsal forefoot. Compression was obtained using a conical...

  7. 急性脑梗死320排 CT 脑灌注成像分析%The analysis of whole-brain CT perfusion imaging with 320-detector row CT in acute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    阮志兵; 段庆红

    2014-01-01

    Objective To explore the clinical value of whole-brain CT perfusion imaging with 320-detector row CT in early acute cerebral infarction.Methods The CTP parameters(CBF,CBV,MTT,TTP)and its pseudo color map of 25 patients with early acute cerebral infarction were retrospectively analysed and compared between infarction area,ischemic penumbra (IP)and the con-tralateral normal region.Results The abnormal perfusion area were found on CTP in 25 patients with early acute cerebral infarction. CTP showed cerebral blood flow (CBF)and cerebral blood volume (CBV)decreased significantly,mean transit time (MTT)short-ened significantly,time to peak (TTP)was significantly longer than those of the contralateral normal region in 7 cases of acute cere-bral infarct core.18 cases of IP lesions showed CBF decreased slightly,CBV increased slightly or maintain normal,MTT and TTP extension compared with contralateral.CBF,CBV,MTT,TTP values had significantly differences between infarct region and the contralateral corresponding normal region,between the infarct core area and IP of acute cerebral infarction (P 0.05)between IP region and the contralateral corresponding normal region,but showed a downward trend in blood flow.Parameter color maps of CTP could di-rectly,clearly and sensitively show abnormal changes region about cerebral blood flow.In particular,MTT and TTP maps shows ab-normal region clearer and sensitively.Follow-up 18 cases of IP,active lesions deduced in 6 cases,the lesions disappeared in 5 pa-tients (CT/ MRI showed no abnormal,and the clinical symptoms disappeared)after thrombolytic therapy,7 cases of MRI and CT scans confirmed infarction stove.Conclusion Whole-brain CTP with 320-detector row CT can early show the acute cerebral infarc-tion and its ischemic penumbra,it has significant important clinical value for early acute cerebral infarction.%目的:探讨320排 CT 全脑灌注成像(CTP)在早期急性脑梗死中的临床应用价值。方法回顾性分析25

  8. Pseudo-asymmetry of cerebral blood flow in arterial spin labeling caused by unilateral fetal-type circle of Willis: Technical limitation or a way to better understanding physiological variations of cerebral perfusion and improving arterial spin labeling acquisition?

    Science.gov (United States)

    Law-Ye, B; Geerts, B; Galanaud, D; Dormont, D; Pyatigorskaya, N

    2016-09-01

    In the recently published article, "Unilateral fetal-type circle of Willis anatomy causes right-left asymmetry in cerebral blood flow with pseudo-continuous arterial spin labeling: A limitation of arterial spin labeling-based cerebral blood flow measurements?", it was shown by the method of arterial spin labeling (ASL) that unilateral fetal-type circle of Willis could induce variation of blood flow in cerebellar and posterior cerebral artery territory. We believe that the reported observation, rather than being a limitation, gives several interesting cues for understanding the ASL sequence. In this commentary, we formulate some suggestions regarding the use of ASL in clinical practice, discuss the potential causes of the above-mentioned pseudo-asymmetry and consider future improvements of the ASL technique.

  9. Cerebral hemodynamics in normal-pressure hydrocephalus. Evaluation by 133Xe inhalation method and dynamic CT study

    Energy Technology Data Exchange (ETDEWEB)

    Tamaki, N.; Kusunoki, T.; Wakabayashi, T.; Matsumoto, S.

    1984-09-01

    Cerebral hemodynamics in 31 patients with suspected normal-pressure hydrocephalus were studied by means of the xenon-133 (133Xe) inhalation method and on dynamic computerized tomography (CT) scanning. Cerebral blood flow (CBF) is reduced in all patients with dementia. Hypoperfusion was noted in a frontal distribution in these patients compared with normal individuals. There was no difference in CBF patterns between patients with good and those with poor outcome. The CBF was increased following cerebrospinal fluid (CSF) shunting in patients who responded to that procedure: increase in flow correlated with clinical improvement, frontal and temporal lobe CBF was most markedly increased, and the CBF pattern became normal. In contrast, CBF was decreased after shunt placement in patients who were considered to have suffered from degenerative dementia, as evidenced by non-response to shunting. Dynamic computerized tomography studies demonstrated that patients with a good outcome showed a postoperative reduction in mean transit time of contrast material, most prominent in the frontal and temporal gray matter, and slight in the deep frontal structures, but not in the major cerebral vessels. Patients with poor outcome after shunting, however, had an increase in transit time in all regions. This corresponded well with the results as determined by the 133Xe inhalation method.

  10. Effects of Topical Bimatoprost 0.01% and Timolol 0.5% on Circadian IOP, Blood Pressure and Perfusion Pressure in Patients with Glaucoma or Ocular Hypertension: A Randomized, Double Masked, Placebo-Controlled Clinical Trial.

    Directory of Open Access Journals (Sweden)

    Francesco Oddone

    Full Text Available To compare the 24-hour (24h effects on intraocular pressure (IOP and cardiovascular parameters of timolol 0.5% and bimatoprost 0.01% in open angle glaucoma and ocular hypertensive subjects.In this prospective, randomized, double masked, crossover, clinical trial, after washout from previous medications enrolled subjects underwent 24h IOP, blood pressure (BP and heart rate (HR measurements and were randomized to either topical bimatoprost 0.01% at night plus placebo in the morning or to timolol 0.5% bid. After 8 weeks of treatment a second 24h assessment of IOP, BP and HR was performed and then subjects switched to the opposite treatment for additional 8 weeks when a third 24h assessment was performed. The primary endpoint was the comparison of the mean 24h IOP after each treatment. Secondary endpoints included the comparisons of IOP at each timepoint of the 24h curve and the comparison of BP, HR, ocular perfusion pressure and tolerability.Mean untreated 24h IOP was 20.3 mmHg (95%CI 19.0 to 21.6. Mean 24h IOP was significantly lower after 8 weeks of treatment with bimatoprost 0.01% than after 8 weeks of treatment with timolol 0.5% bid (15.7 vs 16.8 mmHg, p = 0.0003. Mean IOP during the day hours was significantly reduced from baseline by both drugs while mean IOP during the night hours was reduced by -2.3 mmHg (p = 0.0002 by bimatoprost 0.01% plus placebo and by -1.1 mmHg by timolol 0.5% bid (p = 0.06. Timolol 0.5% significantly reduced the mean 24h systolic BP from baseline, the diastolic BP during the day hours, the HR during the night hours, and the mean 24h systolic ocular perfusion pressure.Both Bimatoprost 0.01% and Timolol 0.5% are effective in reducing the mean 24h IOP from an untreated baseline but Bimatoprost 0.01% is more effective than timolol 0.5% throughout the 24h. Timolol 0.5% effect on IOP is reduced during the night hours and is associated with reduced BP, HR and ocular perfusion pressure.EU Clinical Trial Register and Eudra

  11. Effects of Topical Bimatoprost 0.01% and Timolol 0.5% on Circadian IOP, Blood Pressure and Perfusion Pressure in Patients with Glaucoma or Ocular Hypertension: A Randomized, Double Masked, Placebo-Controlled Clinical Trial

    Science.gov (United States)

    Tanga, Lucia; Berardo, Francesca; Ferrazza, Manuela; Michelessi, Manuele; Roberti, Gloria

    2015-01-01

    Purpose To compare the 24-hour (24h) effects on intraocular pressure (IOP) and cardiovascular parameters of timolol 0.5% and bimatoprost 0.01% in open angle glaucoma and ocular hypertensive subjects. Methods In this prospective, randomized, double masked, crossover, clinical trial, after washout from previous medications enrolled subjects underwent 24h IOP, blood pressure (BP) and heart rate (HR) measurements and were randomized to either topical bimatoprost 0.01% at night plus placebo in the morning or to timolol 0.5% bid. After 8 weeks of treatment a second 24h assessment of IOP, BP and HR was performed and then subjects switched to the opposite treatment for additional 8 weeks when a third 24h assessment was performed. The primary endpoint was the comparison of the mean 24h IOP after each treatment. Secondary endpoints included the comparisons of IOP at each timepoint of the 24h curve and the comparison of BP, HR, ocular perfusion pressure and tolerability. Results Mean untreated 24h IOP was 20.3 mmHg (95%CI 19.0 to 21.6). Mean 24h IOP was significantly lower after 8 weeks of treatment with bimatoprost 0.01% than after 8 weeks of treatment with timolol 0.5% bid (15.7 vs 16.8 mmHg, p = 0.0003). Mean IOP during the day hours was significantly reduced from baseline by both drugs while mean IOP during the night hours was reduced by -2.3 mmHg (p = 0.0002) by bimatoprost 0.01% plus placebo and by -1.1 mmHg by timolol 0.5% bid (p = 0.06). Timolol 0.5% significantly reduced the mean 24h systolic BP from baseline, the diastolic BP during the day hours, the HR during the night hours, and the mean 24h systolic ocular perfusion pressure. Conclusion Both Bimatoprost 0.01% and Timolol 0.5% are effective in reducing the mean 24h IOP from an untreated baseline but Bimatoprost 0.01% is more effective than timolol 0.5% throughout the 24h. Timolol 0.5% effect on IOP is reduced during the night hours and is associated with reduced BP, HR and ocular perfusion pressure. Trial

  12. Perioperative management of patients with lung carcinoma and cerebral metastases

    Science.gov (United States)

    Gheorghita, Eva; Pruna, Viorel Mihai; Neagoe, Luminita; Bucur, Cristina; Cristescu, Catioara; Gorgan, Mircea Radu

    2010-01-01

    ABSTRACT Objective: The present study proposes to present the importance of perioperative therapeutic management in survival prolongation and the quality of life for patients that have undergone surgery for cerebral metastases secondary to pulmonary tumors. Method: During 2001-2009, 40 patients with ages between 43-74 years have been diagnosed in our clinic with pulmonary tumor and cerebral metastases. The patients presented single cerebral lesion (excepting one patient with 2 cerebral metastases) and pulmonary tumor. Intracranial pressure (ICP) was high in all cases. All patients have undergone operation with general anesthesia. Results:For all patients the reduction of ICP and keeping an optimal CPP (cerebral perfusion pressure) was pursued. In 38 cases, general anesthesia was performed with Sevoflurane and opioids (fentanyl, remifentanyl, sufentanyl) and in 2 cases the TIVA (total intravenous anesthesia) technique was used with propofol and remifentanyl. 14 of the patients required intraoperative depletive treatment through administering mannitol 20%. 37 patients (92%) have been discharged with improved neurological condition without showing signs of intracranial hypertension, convulsive seizures and with partially or totally remitted hemiparesis and one patient had worse postoperative neurological status. Conclusion:Pulmonary tumor with cerebral metastases represent an important cause for death rate. To solve secondary cerebral lesions, the perioperative management must include assesment and choosing an anesthesia technique with a proper intraoperative management. PMID:21977115

  13. Brain edema formation correlates with perfusion deficit during the first six hours after experimental subarachnoid hemorrhage in rats

    Directory of Open Access Journals (Sweden)

    Westermaier Thomas

    2012-07-01

    Full Text Available Abstract Background Severe brain edema is observed in a number of patients suffering from subarachnoid hemorrhage (SAH. Little is known about its pathogenesis and time-course in the first hours after SAH. This study was performed to investigate the development of brain edema and its correlation with brain perfusion after experimental SAH. Methods Male Sprague–Dawley rats, randomly assigned to one of six groups (n = 8, were subjected to SAH using the endovascular filament model or underwent a sham operation. Animals were sacrificed 15, 30, 60, 180 or 360 minutes after SAH. Intracranial pressure (ICP, mean arterial blood pressure (MABP, cerebral perfusion pressure (CPP and bilateral local cerebral blood flow (LCBF were continuously measured. Brain water content (BWC was determined by the wet/dry-weight method. Results After SAH, CPP and LCBF rapidly decreased. The decline of LCBF markedly exceeded the decline of CPP and persisted until the end of the observation period. BWC continuously increased. A significant correlation was observed between the BWC and the extent of the perfusion deficit in animals sacrificed after 180 and 360 minutes. Conclusions The significant correlation with the perfusion deficit after SAH suggests that the development of brain edema is related to the extent of ischemia and acute vasoconstriction in the first hours after SAH.

  14. Reversible Cerebral Vasoconstriction Syndrome with Intracranial Hypertension: Should Decompressive Craniectomy Be Considered?

    Science.gov (United States)

    Mrozek, Ségolène; Lonjaret, Laurent; Jaffre, Aude; Januel, Anne-Christine; Raposo, Nicolas; Boetto, Sergio; Albucher, Jean-François; Fourcade, Olivier; Geeraerts, Thomas

    2017-01-01

    Background Reversible cerebral vasoconstriction syndrome (RCVS) is a rare cause of intracerebral hemorrhage (ICH) causing intracranial hypertension. Methods Case report. Results We report a case of RCVS-related ICH leading to refractory intracranial hypertension. A decompressive craniectomy was performed to control intracranial pressure. We discuss here the management of RCVS with intracranial hypertension. Decompressive craniectomy was preformed to avoid the risky option of high cerebral perfusion pressure management with the risk of bleeding, hemorrhagic complications, and high doses of norepinephrine. Neurological outcome was good. Conclusion RCVS has a complex pathophysiology and can be very difficult to manage in cases of intracranial hypertension. Decompressive craniectomy should probably be considered.

  15. Impaired Cerebral Autoregulation during Head Up Tilt in Patients with Severe Brain Injury

    DEFF Research Database (Denmark)

    Riberholt, Christian Gunge; Olesen, Niels Damkjær; Thing, Mira;

    2016-01-01

    acquired brain injury and a low level of consciousness. Fourteen patients with severe acquired brain injury and orthostatic intolerance and fifteen healthy volunteers were enrolled. Blood pressure was evaluated by pulse contour analysis, heart rate and RR-intervals were determined by electrocardiography...... mean velocity and estimated cerebral perfusion pressure. Patients with acquired brain injury presented an increase in mean flow index during head-up tilt indicating impaired autoregulation (P ....1 Hz spectral power in patients compared to healthy controls suggesting baroreflex dysfunction. In conclusion, patients with severe acquired brain injury and orthostatic intolerance during head-up tilt have impaired cerebral autoregulation more than one month after brain injury....

  16. Renal perfusion scintiscan

    Science.gov (United States)

    Renal perfusion scintigraphy; Radionuclide renal perfusion scan; Perfusion scintiscan - renal; Scintiscan - renal perfusion ... supply the kidneys. This is a condition called renal artery stenosis. Significant renal artery stenosis may be ...

  17. CT脑灌注成像临床诊断急性脑梗死价值评价与平扫CT值差值的测量价值%Value Evaluation on Clinical Diagnosis of CT Cerebral Perfusion Imaging on Acute Cerebral infarction and Measurement Value of Difference Value of Plain Scan CT Value

    Institute of Scientific and Technical Information of China (English)

    余东

    2015-01-01

    Objective This Paper is to explore the application value of CT perfusion imaging and differential value of measured CT value in the diagnosis of acute cerebral infarction. Methods Thirty six patients with acute cerebral infarction admitted the Radiology Department of the Hospital were selected as research subjects, retrospective analysis and summary were conducted according to clinical data. CT plaint scan and brain CT perfusion imaging were made respectively, The time to peak (TIP), cerebral blood flow (CBF) and cerebral blood volume (CBV) of CT perfusion imaging were evaluated, the difference of CT value on both sides of symmetric positions was measured. In addition, 36 patients with no brain disease and normal nervous function were divided into the control group, and diagnostic value of the difference between CT perfusion imaging and CT measurement value in acute cerebral infarction was analyzed. Results It is visually found that there were 17 patients with suspicious lesions with the sensitivity at 47.2%, and it was found that there were 28 patients with suspicious lesions by measuring CT value difference. It was found that the CTP of 3 patients was normal CT perfusion imaging examination, and such 2 patients were finally diagnosed to suffer from transient ischemic attack, and others were abnomal, rCBF, rCBV and rTTP changed obviously, the comparison in lesion center and perimeter and controlled side satisfied p<0.05, and the differences were statistically significant. Conclusion CT perfusion imaging and the difference value in CT value measurement delivers high application value in the diagnosis of acute cerebral infarction, and it is capable of diagnosing cerebral infarction in early differential diagnosis, the infarct area and ischemic penumbra area may be differentiated via through quantitative analysis, providing important basis for clinical determination on the existence of infarct and development of therapeutic schedule.%目的:探讨CT灌注成像

  18. Comparison of cerebral perfusion reserve and collateral circulation in patients with internal carotid artery disease; Die zerebrale Perfusionsreserve in Abhaengigkeit vom Kollateralisierungstyp bei Patienten mit A.-carotis-interna-Stenosen/-Verschluessen

    Energy Technology Data Exchange (ETDEWEB)

    Reiche, W.; Schaefer, R.; Hermes, M. [Abt. fuer Neuroradiologie, Radiologische Klinik der Universitaet des Saarlandes, Homburg/Saar (Germany); Mueller, M. [Neurologische Klinik der Universitaet des Saarlandes, Homburg/Saar (Germany)

    1997-11-01

    The cerebral hemodynamics in patients with carotid disease is influenced by a network of extra- and intracranial collaterals. The purpose of this study was to compare the findings of regional cerebral perfusion reserve (rCPR) with angiographically proven collateral circulation. In 41 patients (28 men, 13 women, age 63{+-}10 years) with angiographically proven carotid stenoses or occlusions (30 stenoses, 11 occlusions) 24 {sup 99m}Tc-HMPAO-SPECT and 25 dynamic Xe-CT investigations were conducted, both before and after acetazolamide stimulation. rCPR was quantified as the ratio (1) of the absolute rCBF values obtained by Xe-CT and (2) of the count density measured by HMPAO-SPECT of the acetazolamide administration. A rCPR of less than 95% in a vascular territory was classified as compromised rCPR. A recent CT examination was available in all cases. According to the angiographic findings the patients could be classified into (1) group A (n=9) with residual carotid perfusion, (2) Group B (n=8) with collateralization via the circle of Willis, and (3) group C (n=24) with leptomeningeal or opthalmic artery collateral circulation. (orig./AJ) [Deutsch] Die zerebrale Haemodynamik bei A.-carotis-interna-(ACI-)Stenosen/-Verschluessen wird von extra- und intrakaniellen Kollateralen beeinflusst. Ziel dieser Studie war es, die Befunde der regionalen zerebralen Perfusionsreserve (rCPR) mit angiographisch nachgewiesenen Kollateralisierungs- und Anastomosierungstypen zu vergleichen. Bei 41 Patienten (28 Maennder, 13 Frauen, Alter 63{+-}10 Jahre) mit angiographisch untersuchten ACl-Stenosen/-Verschluessen (30 Stenosen, 11 Verschluesse) wurden in 24 Faellen eine {sup 99m}Tc-HMPAO-SPECT und in 25 eine dynamische Xe-CT jeweils vor und nach Diamox{sup R}-Stimulation durchgefuehrt. Fuer die rCPR-Quantifizierung wurde in der Xe-CT das Verhaeltnis der absoluten rCBF-Werte und in der HMPAO-SPECT der Zaehlratendichten jeweils nach zu vor Diamox berechnet. Eine rCPR<95% in einem zerebralen

  19. Quantitative Cerebral Blood Flow Measurements Using MRI

    OpenAIRE

    Muir, Eric R; Watts, Lora Talley; Tiwari, Yash Vardhan; Bresnen, Andrew; Timothy Q Duong

    2014-01-01

    Magnetic resonance imaging utilized as a quantitative and noninvasive method to image cerebral blood flow. The two most common techniques used to detect cerebral blood flow are dynamic susceptibility contrast (DSC) perfusion MRI and arterial spin labeling perfusion MRI. Herein we describe the use of these two techniques to measure cerebral blood flow in rodents, including methods, analysis, and important considerations when utilizing these techniques.

  20. Perfusion harmonic imaging of the human brain

    Science.gov (United States)

    Metzler, Volker H.; Seidel, Guenter; Wiesmann, Martin; Meyer, Karsten; Aach, Til

    2003-05-01

    The fast visualisation of cerebral microcirculation supports diagnosis of acute cerebrovascular diseases. However, the commonly used CT/MRI-based methods are time consuming and, moreover, costly. Therefore we propose an alternative approach to brain perfusion imaging by means of ultrasonography. In spite of the low signal/noise-ratio of transcranial ultrasound and the high impedance of the skull, flow images of cerebral blood flow can be derived by capturing the kinetics of appropriate contrast agents by harmonic ultrasound image sequences. In this paper we propose three different methods for human brain perfusion imaging, each of which yielding flow images indicating the status of the patient's cerebral microcirculation by visualising local flow parameters. Bolus harmonic imaging (BHI) displays the flow kinetics of bolus injections, while replenishment (RHI) and diminution harmonic imaging (DHI) compute flow characteristics from contrast agent continuous infusions. RHI measures the contrast agents kinetics in the influx phase and DHI displays the diminution kinetics of the contrast agent acquired from the decay phase. In clinical studies, BHI- and RHI-parameter images were found to represent comprehensive and reproducible distributions of physiological cerebral blood flow. For DHI it is shown, that bubble destruction and hence perfusion phenomena principally can be displayed. Generally, perfusion harmonic imaging enables reliable and fast bedside imaging of human brain perfusion. Due to its cost efficiency it complements cerebrovascular diagnostics by established CT/MRI-based methods.

  1. Cerebral autoregulation and flow/metabolism coupling during cardiopulmonary bypass: the influence of PaCO/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Murkin, J.M.; Farrar, J.K.; Tweed, W.A.; McKenzie, F.N.; Guiraudon, G.

    1987-09-01

    Measurement of /sup 133/Xe clearance and effluent cerebral venous blood sampling were used in 38 patients to determine the effects of cardiopulmonary bypass, and of maintaining temperature corrected or noncorrected PaCO/sub 2/ at 40 mm Hg on regulation of cerebral blood flow (CBF) and flow/metabolism coupling. After induction of anesthesia with diazepam and fentanyl, mean CBF was 25 ml X 100 g-1 X min-1 and cerebral oxygen consumption, 1.67 ml X 100 g-1 X min-1. Cerebral oxygen consumption during nonpulsatile cardiopulmonary bypass at 26 degrees C was reduced to 0.42 ml X 100 g-1 X min-1 in both groups. CBF was reduced to 14-15 ml X 100 g-1 X min-1 in the non-temperature-corrected group (n = 21), was independent of cerebral perfusion pressure over the range of 20-100 mm Hg, but correlated with cerebral oxygen consumption. In the temperature-corrected group (n = 17), CBF varied from 22 to 32 ml X 100 g-1 X min-1, and flow/metabolism coupling was not maintained (i.e., CBF and cerebral oxygen consumption varied independently). However, variation in CBF correlated significantly with cerebral perfusion pressure over the pressure range of 15-95 mm Hg. This study demonstrates a profound reduction in cerebral oxygen consumption during hypothermic nonpulsatile cardiopulmonary bypass. When a non-temperature-corrected PaCO/sub 2/ of approximately 40 mm Hg was maintained, CBF was lower, and analysis of pooled data suggested that CBF regulation was better preserved, i.e., CBF was independent of pressure changes and dependent upon cerebral oxygen consumption.

  2. A voxel-based analysis of cerebral perfusion with {sup 99m}Tc-ECD brain SPECT in obsessive-compulsive disorder

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Tae Joo; Lee, Jong Doo; Kim, Hee Joung; Chang, Jin Woo; Kim, Chan Hyung; Lee, Hong Shick; Min, Sung Kil; Chung, Sang Sup [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of)

    2000-07-01

    Many neuroimaging studies, especially metabolic imaging with PET, showed a specific frontal-subcortical brain circuit connecting the orbitofrontal cortex (OFC), anterior cingulate gyrus, elements of basal ganglia and thalamus is involved in obsessive-compulsive disorder (OCD). Despite consistent metabolic alteration on PET, blood flow studies with SPECT were inconsistent and various cortical and subcortical structures showed abnormal perfusion patterns. In this study, brain SPECT images of seven patients with OCD were evaluated with a sophisticated method of statistical parametric mapping (SPM). Seven patients with severe, primary OCD (6 males and 1 female) with mean age of 25.4 4.7 yrs (20-32 yrs) were studied. The SPECT data of the patients were compared with those of healthy subjects and patients with drug nave schizophrenia using SPM. The SPM parameters were p value of 0.001 with Z value of 3.09 (higher threshold ) or p value of 0.005 with Z value 2.58 (lower threshold). On a higher threshold (p<0.01),five of the seven patients showed hyperperfusion within the anterior cingulate cortex, however, hyperperfusion within OFC or caudate nucleus was seen in only one patient. On a lower threshold (p<0.005), hyperperfusion within the anterior cingulate cortex was seen in all patients, and followed by thalamus (n=5), lentiform nucleus (n=4), caudate nucleus (n=3), and OFC (n=3). Perfusion within the anterior cingulate cortex was also increased in OCD compared with drug nave schizophrenia. Anterior cingulate cortex appears to be an important anatomical structure in the pathogenesis of OCD symptoms. Brain SPECT using a sophisticated analysis method of SPM is useful for the diagnosis of OCD and differentiation from schizophrenia.

  3. Evaluation of the Extension of the Cerebral Blood Flow and its Main Parameters

    CERN Document Server

    Gersten, A

    1999-01-01

    Among the major factors controlling the cerebral blood flow (CBF) - cerebral perfusion pressure, arterial partial pressure of oxygen (PaO2), cerebral metabolism, arterial partial pressure of carbon dioxide (PaCO2), and cardiac output, the effect of PaCO2 is peculiar in being independent of autoregulatory CBF mechanisms and it allows to explore the full range of the CBF. We have developed a simple physical model, and have derived a simple four parameter formula, relating the CBF to PaCO2. The parameters can be extracted in an easy way, directly from the experimental data. With this model five experimental data sets of human, rats, baboons and dogs were well fitted. The same type of parametrization was also used successfully for fitting experimental data of PaO2 of dogs. We have also looked on the dependence of the parameters on other factors and were able to evaluate their dependence on the mean arterial blood pressure.

  4. CT Perfusion ASPECTS in the Evaluation of Acute Ischemic Stroke: Thrombolytic Therapy Perspective

    Directory of Open Access Journals (Sweden)

    Niko Sillanpaa

    2011-02-01

    Full Text Available Background and Purpose: Advances in the management of acute ischemic stroke and medical imaging are creating pressure to replace the rigid one-third middle cerebral artery (MCA and non-contrast-enhanced CT (NCCT Alberta Stroke Program Early CT Score (ASPECTS thresholds used for the selection of patients eligible for intravenous thrombolytic therapy. The identification of potentially salvageable ischemic brain tissue lies at the core of this issue. In this study, the role of CT perfusion ASPECTS in the detection of reversible ischemia was analyzed. Materials and Methods: We retrospectively reviewed the clinical and imaging data of 92 consecutive patients who received intravenous thrombolytic therapy for acute (duration Results: A perfusion defect could be detected in 50% of the patients. ASPECTS correlated inversely with the clinical outcome in the following order: follow-up NCCT > cerebral blood volume (CBV > mean transit time (MTT > admission NCCT. The follow-up NCCT and the CBV displayed a statistically significant difference from the admission NCCT, while the MTT did not reach statistical significance. The threshold that best differentiated between good and bad clinical outcome on admission was CBV ASPECTS ≧7. In patients with CT perfusion ASPECTS mismatch, MTT and CBV ASPECTS essentially provided the lower and upper limits for the follow-up NCCT ASPECTS, thus defining the spectrum of possible outcomes. Furthermore, CT perfusion ASPECTS mismatch strongly correlated (r = 0.83 with the mismatch between the tissue at risk and the final infarct, i.e. the amount of salvaged tissue. This finding suggests that the CT perfusion ASPECTS mismatch adequately identifies the amount of potentially salvageable ischemic brain tissue. Conclusions: Parameters derived from the use of CT perfusion ASPECTS can detect reversible ischemia and are correlated with clinical outcome.

  5. Blood pressure and sodium: Association with MRI markers in cerebral small vessel disease

    OpenAIRE

    Heye, Anna K.; Thrippleton, Michael J; Chappell, Francesca M; Valdés Hernández, Maria del C.; Armitage, Paul A.; Makin, Stephen D.; Muñoz Maniega, Susana; Sakka, Eleni; Flatman, Peter W.; Dennis, Martin S.; Wardlaw, Joanna M.

    2016-01-01

    Dietary salt intake and hypertension are associated with increased risk of cardiovascular disease including stroke. We aimed to explore the influence of these factors, together with plasma sodium concentration, in cerebral small vessel disease (SVD). In all, 264 patients with nondisabling cortical or lacunar stroke were recruited. Patients were questioned about their salt intake and plasma sodium concentration was measured; brain tissue volume and white-matter hyperintensity (WMH) load were m...

  6. Equal contribution of increased intracranial pressure and subarachnoid blood to cerebral blood flow reduction and receptor upregulation after subarachnoid hemorrhage. Laboratory investigation

    DEFF Research Database (Denmark)

    Ansar, Saema; Edvinsson, Lars

    2009-01-01

    OBJECT: Cerebral ischemia remains the key cause of disability and death in the late phase after subarachnoid hemorrhage (SAH), and its pathogenesis is still poorly understood. The purpose of this study was to examine whether the change in intracranial pressure or the extravasated blood causes...... the late cerebral ischemia and the upregulation of receptors or the cerebral vasoconstriction observed following SAH. METHODS: Rats were allocated to 1 of 3 experimental conditions: 1) cisternal injection of 250 microl blood (SAH Group), 2) cisternal injection of 250 microl NaCl (Saline Group), or 3......) the same procedure but without fluid injection (Sham Group). Two days after the procedure, the basilar and middle cerebral arteries were harvested, and contractile responses to endothelin (ET)-1 and 5-carboxamidotryptamine (5-CT) were investigated by means of myography. In addition, real-time polymerase...

  7. The new factors defining variability of circadian’s rhythms of intraocular and perfusion pressure of glaucoma patients

    Directory of Open Access Journals (Sweden)

    N. A. Baranova

    2016-01-01

    Full Text Available Currently, the most scientifically based local risk and progressive factors are elevated levels of intraocular pressure and its instability during the day, caused by local hydromechanical disturbances. However, the other factors affecting the circadian changes of intraocular pressure levels are still evaluated. It was found that light is one of the most important factors affecting the intensity of the cyclical fluctuations of various biological processes, including, and fluctuations of intraocular pressure. At the same time, glaucoma can lead to a variety of sleep disorders, due to a mismatch between cycles «sleep-wake». One if this reason is the death of retinal ganglion cells and their axons. Such damage indirectly lead to a decrease in production of the pigment melanopsin, which is located in the retina. It is not involved in the visual process, but ensures the implementation of circadian rhythms «sleep-wake» and mediated suppression of epiphyseal melatonin. Most likely, melatonin plays a protective role in the occurrence and progression of glaucoma, protecting retinal cells against free radicals and has a direct impact on the intraocular pressure level. Several studies have shown that the circadian change in intraocular pressure levels, and in particular, its substantial reduction, is influenced by melatonin. In this regard, glaucoma is a disease in which the death of retinal cells, including producing melanopsin, a unique opportunity to study violations of cyclic rhythms. Melatonin acts on such established risk factors and progression of glaucoma as hypertension and diabetes. There are published results of the use of melatonin agonists in the experiment and clinical practice. So, in addition to local and systemic hypotensive action, normalizes sleep patients. Data about the melatonin’s effects on the direct and indirect reduction of intraocular pressure, neuroprotective effects and reducing symptoms of depression can

  8. Time-varying modeling of cerebral hemodynamics.

    Science.gov (United States)

    Marmarelis, Vasilis Z; Shin, Dae C; Orme, Melissa; Rong Zhang

    2014-03-01

    The scientific and clinical importance of cerebral hemodynamics has generated considerable interest in their quantitative understanding via computational modeling. In particular, two aspects of cerebral hemodynamics, cerebral flow autoregulation (CFA) and CO2 vasomotor reactivity (CVR), have attracted much attention because they are implicated in many important clinical conditions and pathologies (orthostatic intolerance, syncope, hypertension, stroke, vascular dementia, mild cognitive impairment, Alzheimer's disease, and other neurodegenerative diseases with cerebrovascular components). Both CFA and CVR are dynamic physiological processes by which cerebral blood flow is regulated in response to fluctuations in cerebral perfusion pressure and blood CO2 tension. Several modeling studies to date have analyzed beat-to-beat hemodynamic data in order to advance our quantitative understanding of CFA-CVR dynamics. A confounding factor in these studies is the fact that the dynamics of the CFA-CVR processes appear to vary with time (i.e., changes in cerebrovascular characteristics) due to neural, endocrine, and metabolic effects. This paper seeks to address this issue by tracking the changes in linear time-invariant models obtained from short successive segments of data from ten healthy human subjects. The results suggest that systemic variations exist but have stationary statistics and, therefore, the use of time-invariant modeling yields "time-averaged models" of physiological and clinical utility.

  9. Middle cerebral artery blood velocity during rowing

    DEFF Research Database (Denmark)

    Secher, Niels Henry; Pott, F; Knudsen, L.;

    1997-01-01

    original,arterial blood pressure,central venous pressure,cerebral blood flow, exercise, transcranial Doppler......original,arterial blood pressure,central venous pressure,cerebral blood flow, exercise, transcranial Doppler...

  10. CT脑灌注成像在短暂性脑缺血发作的应用价值探讨%To Study the Application Value of CT Cerebral Perfusion Imaging in Transient Ischemic Attack

    Institute of Scientific and Technical Information of China (English)

    杜彦挺; 夏志强; 杜光勇; 张伟; 李涛

    2016-01-01

    目的:探讨CT脑灌注成像(CT perfusion,CTP)在短暂性脑缺血发作(transient ischemic attack,TIA)的应用价值。方法收集我院从2013年4月至2015年4月收治的55例短暂性TIA患者作为研究对象,发病24h内进行CTP和CTA(CT angiography)检查,发病72h内进行头颅MRI(magnetic resonance imaging)和MRA(magnetic resonance angiography)进行检查,比较CTP与其他检查方法的检出结果差异,并对病灶侧与健康侧的脑灌注成像参数如获得达峰时间(time to peak, TTP)、平均通过时间(mean transit time, MTT)、脑血流量(cerebral blood flow, CBF)、脑血容量(cerebral blood volume, CBV)进行比较分析。结果 CTA检出35个病灶,MRI检出44个病灶,CTP检出59个病灶,CTP对病灶的检出率高于CTA和MR检查,具有统计学意义(P<0.05);CTP检出的病灶表现分型中I1期12个,I2期29个,II1期11个, II2期7个,I2期明显多于其他分型,具有统计学意义(P<0.05);CTP病灶侧的TTP值、MTT值(P<0.05);CTP病灶侧的CBV值与健康侧没有明显差异(P>0.05)。结论采用CT脑灌注成像检查短暂性脑缺血发作可以全面的诊断,对治疗短暂性脑缺血发作提供可靠的依据。%Objective To study the application value of CT cerebral perfusion imaging(CTP) in Transient ischemic attack(TIA).Methods Fifty-five cases of transient ischemic attack from April 2013 to April 2015 in our hospital were collected as research subject, all of them were performed CTP, CTA(CT angiography) in 24 hours after onset and MRI(Magnetic Resonance imaging) and MRA(Magnetic Resonance angiography) in 72 hours. The inspection results of CTA and MRI and CTP were compared, and the parameters of CTP like time to peak(TTP), mean transit time(MTT), cerebral blood flow(CBF), cerebral blood volume(CBV) were analyzed and compared between lesion side and healthy side.Results Thirty-five lesions were checked out by CTA inspection, 44 lesions by MRI, and 59

  11. Cerebral blood flow and metabolism analysis in parkinsonian disorders; Pathologie extrapyramidale. Apport de l'imagerie de perfusion et du metabolisme (TEP, TEM)

    Energy Technology Data Exchange (ETDEWEB)

    Defebvre, L. [Hopital Roger Salengro, Service de Neurologie, 59 - Lille (France)

    1999-12-01

    Main metabolic and hemodynamic abnormalities detected by single photon emission computerized tomography and positron emission tomography in extra-pyramidal disorders are reported. In the first stage of Parkinson's disease, cortical metabolism and perfusion can be in normal range or moderately and uniformly reduced. A significant decrease may appear with the disease evolution. Marked abnormalities are observed in parkinsonian patients with dementia (subcortical dementia), involving especially the frontal cortex. A marked diffuse cortical hypo-metabolism (temporal, parietal, occipital and frontal cortex) may suggest the diagnosis of dementia with Lewy bodies, especially in case of fluctuating cognitive decline with recurrent visual hallucinations. In progressive supra-nuclear palsy, a frontal cortex hypo-metabolism is reported precociously, preceding sometimes the cognitive impairment. Metabolic pattern find in multiple system atrophy reflects dysfunction of both nigrostriatal pathways and striatum, with a decrease glucose uptake in putamen and caudate nucleus which also involves cerebellum for the patients with cerebellar syndrome. In cortico-basal degeneration, asymmetric fronto-parietal and striatal hypo-metabolism observed in the controlateral hemisphere to the clinically most affected side, constitute the main characteristic well correlated with apraxia. (author)

  12. Cerebral Edema in Chronic Mountain Sickness: a New Finding

    Science.gov (United States)

    Bao, Haihua; Wang, Duoyao; Zhao, Xipeng; Wu, Youshen; Yin, Guixiu; Meng, Li; Wang, Fangfang; Ma, Lan; Hackett, Peter; Ge, Ri-Li

    2017-01-01

    We observed patients with chronic mountain sickness (CMS) in our clinic who developed progressive neurological deterioration (encephalopathy) and we wished to investigate this. We studied nine such CMS patients, and compared them to 21 CMS patients without encephalopathy, and to 15 healthy control subjects without CMS. All 45 subjects lived permanently at 3200–4000 m. Measurements at 2260 m included CMS symptom score, multi-slice CT, perfusion CT, pulse oximetry (SpO2%), and hemoglobin concentration (Hb). One patient had MRI imaging but not CT; 5 had CSF pressure measurements. CMS subjects had lower SpO2, higher Hb, higher brain blood density, lower mean cerebral blood flow (CBF), and significant cerebral circulatory delay compared to controls. The nine CMS subjects with neurological deterioration showed diffuse cerebral edema on imaging and more deranged cerebral hemodynamics. CSF pressure was elevated in those with edema. We conclude that cerebral edema, a previously unrecognized complication, may develop in CMS patients and cause encephalopathy. Contributing factors appear to be exaggerated polycythemia and hypoxemia, and lower and sluggish CBF compared to CMS patients without cerebral edema; but what triggers this complication is unknown. Recognition and treatment of this serious complication will help reduce morbidity and mortality from CMS. PMID:28233815

  13. Influence of upper body position on middle cerebral artery blood velocity during continuous positive airway pressure breathing

    DEFF Research Database (Denmark)

    Højlund Rasmussen, J; Mantoni, T; Belhage, B;

    2007-01-01

    in 11 healthy subjects during CPAP at different body positions (15 degrees head-down tilt, supine, 15 degrees, 30 degrees and 45 degrees upper body elevation). In the supine position, 10 cmH(2)O of CPAP reduced MCA V(mean) by 9 +/- 3% and increased cHbT by 4 +/- 2 micromol/L (mean +/- SEM); (P ....05). In the head-down position, CPAP increased cHbT to 13 +/- 2 micromol/L but left MCA V(mean) unchanged. Upper body elevation by 15 degrees attenuated the CPAP associated reduction in MCA V(mean) (-7 +/- 2%), while cHbT returned to baseline (1 +/- 2 micromol/L). With larger elevation of the upper body MCA V......Continuous positive airway pressure (CPAP) is a treatment modality for pulmonary oxygenation difficulties. CPAP impairs venous return to the heart and, in turn, affects cerebral blood flow (CBF) and augments cerebral blood volume (CBV). We considered that during CPAP, elevation of the upper body...

  14. Cerebral hemodynamics and functional prognosis in hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Hirai, Osamu; Nishikawa, Michio; Watanabe, Shu; Yamakawa, Hiroyasu; Kinoshita, Yoshimasa; Uno, Akira; Handa, Hajime (Hamamatsu Rosai Hospital, Shizuoka (Japan))

    1989-11-01

    The functional outcome of cerebral hemodynamics in the chronic stage of juvenile hydrocephalus was determined using single photon emission computed tomography (SPECT). Five patients including three with aqueductal stenosis, one with post-meningitic hydrocephalus, and one case with hydrocephalus having developed after repair of a huge occipital encephalocele. Early images of cerebral blood flow (CBF) were obtained 25 minutes after intravenous injection of 123-I-iodoamphetamine (IMP), and late images were scanned 3 hours later. Cerebral blood volume (CBV) was also measured using {sup 99m}Tc in three patients. Twenty cases with adult communicating hydrocephalus were also investigated from the point of view of shunt effectiveness. Although there was no remarkable change in the cerebrovascular bed in the juvenile cases, CBF of the remnant brain parenchyma was good irrespective of the degree of ventricular dilatation. There was a periventricular-related IMP uptake in each case; however, it somehow matched the ventricular span. Functional outcome one to 23 years after the initial shunt operation was good in every case, despite multiple shunt revisions. Redistribution on late images had no bearing on clinical states. In adult cases, 8 patients with effective shunting demonstrated a relatively localized periventricular low perfusion, with preoperative increased cerebrospinal fluid (CSF) pressure. On the contrary, 12 patients with no improvement with or without ventricular-reduced IMP uptake, despite low CSF pressure. The present study indicates that periventricular hemodynamics may play an important role in cerebral function compromised by hydrocephalus. (J.P.N.).

  15. INTRACRANIAL PRESSURE MONITORING TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Ida Bagus Adi Kayana

    2013-03-01

    Full Text Available Head injury is the most significant cause of increased morbidity and mortality. An estimated 1.4 million head injuries occur each year, with and more than 1.1 million come to the Emergency Unit. On each patient head injury, an increase in intracranial pressure (ICP related to poor outcomes and aggressive therapy to increased ICP can improve the outcomes. ICP monitoring is the most widely used because of the prevention and control of ICP as well as maintain the pressure increase perfusion of cerebral (Cerebral Perfusion Pressure/CPP is the basic purpose of handling head injury. There are two methods of monitoring ICP that is an invasive methods (directly and non-invasive techniques (indirectly. The method commonly used, namely intraventricular and intraparenkimal (microtransducer sensor because it is more accurate but keep attention to the existence of the risk of bleeding and infection resulting from installation. Monitoring of ICT can determine the actions that avoid further brain injury, which can be lethal and irreversibel.

  16. Equal contribution of increased intracranial pressure and subarachnoid blood to cerebral blood flow reduction and receptor upregulation after subarachnoid hemorrhage. Laboratory investigation

    DEFF Research Database (Denmark)

    Ansar, Saema; Edvinsson, Lars

    2009-01-01

    OBJECT: Cerebral ischemia remains the key cause of disability and death in the late phase after subarachnoid hemorrhage (SAH), and its pathogenesis is still poorly understood. The purpose of this study was to examine whether the change in intracranial pressure or the extravasated blood causes the...

  17. Beneficial effect of epinephrine infusion on cerebral and myocardial blood flows during CPR.

    Science.gov (United States)

    Koehler, R C; Michael, J R; Guerci, A D; Chandra, N; Schleien, C L; Dean, J M; Rogers, M C; Weisfeldt, M L; Traystman, R J

    1985-08-01

    It is hypothesized that epinephrine improves the ability to resuscitate the heart through a mechanism thought to be related to the increase in aortic pressure. Our results with epinephrine infusion during CPR are consistent with this hypothesis. Epinephrine selectively increased vascular resistance in noncerebral, noncoronary vascular beds, as indicated by a decrease in microsphere-determined blood flow in these areas. This increased vascular resistance raised aortic pressure during the chest compression phase and the relaxation phase of CPR. Because intracranial and right atrial pressures were only slightly higher with epinephrine, cerebral and myocardial perfusion pressures and blood flows were significantly improved. This beneficial effect (compared to no administration of a vasopressor) was more pronounced as CPR progressed beyond ten minutes. Enhanced cerebral and myocardial perfusion occurred with epinephrine when either the conventional or simultaneous compression and ventilation (SCV) mode of CPR was employed in dogs. Similar selective perfusion was sustained for 50 minutes of SCV-CPR with epinephrine, even when the onset of CPR was delayed five minutes. Regional brain blood flow differed in the delayed-CPR group in that cerebellum, brain stem, and thalamic regions initially had higher blood flows. In an infant animal model of CPR using conventional CPR in piglets, epinephrine also was found to increase cerebral and myocardial blood flows. These results show that administration of epinephrine benefits different age groups of different species with different modes of CPR; that benefits occur even with delayed onset of CPR which is associated with additional anoxia and acidosis; and that epinephrine administration is particularly effective in sustaining cerebral and coronary perfusion during prolonged CPR.

  18. Photoacoustic & pulsed laser-doppler monitoring of blood concentration and perfusion in tissue

    OpenAIRE

    Kolkman, Roy Gerardus Maria

    2002-01-01

    In medicine there are situations that require continuous bedside monitoring of perfusion and blood volume. Such a situation can occur when children are born prematurely. Those children have a high risk to develop a handicap, which is most likely caused by cerebral damage due to impaired brain perfusion. Monitoring cerebral perfusion can provide information for preventive treatment. In this thesis we have explored the potential of photoacoustics and laser Doppler flowmetry for measurement of c...

  19. Cerebral hemodynamics in patients with obstructive sleep apnea syndrome monitored with near-infrared spectroscopy (NIRS) during positive airways pressure (CPAP) therapy: a pilot study

    Science.gov (United States)

    Zhang, Zhongxing; Schneider, Maja; Laures, Marco; Fritschi, Ursula; Lehner, Isabella; Qi, Ming; Khatami, Ramin

    2014-03-01

    In obstructive sleep apnea syndrome (OSA) the periodic reduction or cessation of breathing due to narrowing or occlusion of the upper airway during sleep leads to daytime symptoms and increased cardiovascular risk, including stroke. The higher risk of stroke is related to the impairment in cerebral vascular autoregulation. Continuous positive airways pressure (CPAP) therapy at night is the most effective treatment for OSA. However, there is no suitable bedside monitoring method evaluating the treatment efficacy of CPAP therapy, especially to monitor the recovery of cerebral hemodynamics. NIRS is ideally suited for non-invasive monitoring the cerebral hemodynamics during sleep. In this study, we will for first time assess dynamic changes of cerebral hemodynamics during nocturnal CPAP therapy in 3 patients with OSA using NIRS. We found periodic oscillations in HbO2, HHb, tissue oxygenation index (TOI) and blood volume associated with periodic apnea events without CPAP in all OSA patients. These oscillations were gradually attenuated and finally eliminated with the stepwise increments of CPAP pressures. The oscillations were totally eliminated in blood volume earlier than in other hemodynamic parameters. These results suggested that 1) the cerebral hemodynamic oscillations induced by OSA events can effectively be attenuated by CPAP therapy, and 2) blood flow and blood volume recovered first during CPAP therapy, followed by the recovery of oxygen consumption. Our study suggested that NIRS is a useful tool to evaluate the efficacy of CPAP therapy in patients with OSA bedside and in real time.

  20. Dopamine therapy does not affect cerebral autoregulation during hypotension in newborn piglets

    DEFF Research Database (Denmark)

    Eriksen, Vibeke Ramsgaard; Rasmussen, Martin Bo; Hahn, Gitte Holst;

    2017-01-01

    lead to a rightward shift of the cerebral autoregulatory curve; consequently, infants treated with dopamine would have a higher risk of low cerebral blood flow at a blood pressure that is otherwise considered "safe". METHODS: In anaesthetized piglets, perfusion of the brain, monitored with laser...... phase, and the infusion rate of dopamine (10, 25, or 40 μg/kg/min). In/deflation of a balloon catheter, placed in vena cava, induced different levels of hypotension. At each level of hypotension, fluctuations in MAP were induced by in/deflations of a balloon catheter in descending aorta. RESULTS: During...

  1. Correlation between hepatic CT perfusion imaging and portal vein pressure in normal Beagles%肝脏CT灌注成像与门静脉压力相关性的动物实验研究

    Institute of Scientific and Technical Information of China (English)

    林元为; 陈伟建; 张启瑜; 梁盼; 杨博洋

    2011-01-01

    目的:探讨正常比格犬门静脉压力与肝脏CT血流灌注参数的相关性.方法:采用螺旋CT对24只犬行肝脏灌注成像扫描,去卷积法计算肝脏血流灌注参数,包括血流量(blood flow,BF)、血容量(blood volume,BV)、平均通过时间(mean transit time,MTT)、肝动脉分数(hepatic arterial fraction,HAF)、肝动脉灌注量(hepatic arterial perfusion,HAP)、门静脉灌注量(portal venous perfusion,PVP).扫描后3 d内开腹,采用玻璃水柱法测定门静脉压力.利用直线回归与相关分析门静脉压力与肝脏CT血流灌注参数的相关性.结果:(1)正常比格犬实测门静脉压力值为(13.57±1.15)cmH2O.(2)正常比格犬门静脉压力与BF、PVP呈负相关,与HAF呈正相关,其中以PVP相关性最显著(r=-0.764,P<0.05),两者关系的直线回归方程为Y=16.507-0.037X.结论:肝脏CT灌注成像为无创、有效监测门静脉压力提供了一种新途径.%Objective To evaluate the correlation between the parameters of spiral CT perfusion imaging and portal vein pressure in normal Beagles. Methods Twenty-four normal beagles were selected to receive hepatic spiral CT perfusion imaging. The parameters of hepatic perfusion , including blood flow (BF) , blood volume (BV) ,mean transit time ( MTT) , hepatic arterial fraction ( HAF) , hepatic arterial perfusion ( HAP) , and portal venous perfusion (PVP) , were calculated hy the method of deconvolution. The portal vein pressure was measured by glass column method in laparotomy surgery three days after CT imaging. Results Portal vein pressure of the beagles were ( 13.57 ± 1.15) cmH2O. Portal vein pressure was negatively correlated with the BF and PVP , but was positively correlated with HAF. PVP was the most significant parameter that correlated with portal vein pressure (r = -0.764,P<0.05) , and their linear regression equation was Y = 16.507-0.037X. Conclusion CT perfusion imaging is a new non-invasive and eff'ective method for assessing portal vein

  2. Application Research on Multi-slice Spiral CT Perfusion Imaging in Patients with Acute Cerebral Infarction%多层螺旋 CT 灌注成像在急性脑梗死患者的应用研究

    Institute of Scientific and Technical Information of China (English)

    罗友琛

    2014-01-01

    目的:探讨急性脑梗死患者多层螺旋 CT 灌注成像特点,及其与临床预后的关系。方法选择符合标准的患者40例,行 CT 灌注成像检查,计算脑血流量(CBF)、脑血容量(CBV)、平均通过时间(MTT)及峰值时间(TTP);分别在入院时和治疗后14d 采用美国国立卫生研究院卒中量表(NIHSS)评价临床神经功能缺损,计算缺血脑组织的可恢复比率(PRR)和神经功能恢复比率。结果脑梗死病灶中心 CBV 及 CBF 最低,健侧最高,而缺血半暗带居中,差异有统计学意义(P 0.05);PRR 与患者治疗14d 时 NIHSS 评分存在负相关性(r =-0.340, P 0. 05),negatively dependent of those at day 14 after treatment (r = - 0. 340,P < 0. 05) and positive-ly dependent of patient’s neural functional recovery ratio (r = 0. 467,P < 0. 05). Conclusion Multi-slice spiral CT perfusion im-aging can reflecthemodynamic changes in acute cerebral infarction lesions and their perihemodynamic changes. PRR is closely de-pendent of the neural functional recovery. It can serve as a reliable theoretical basis for clinical treatment.

  3. Evaluation of stenosis degree of the middle cerebral artery with high-resolution MRI and brian blood supply with MR perfusion weighted imaging%高分辨率MRI评价大脑中动脉狭窄程度与灌注加权成像评估脑供血的研究

    Institute of Scientific and Technical Information of China (English)

    崔恒; 程敬亮; 张勇

    2012-01-01

    Objective To study the value of high-resolution MRI(HRMRI) and MR perfusion weighted imaging(PWI) in evaluating the middle cerebral artery (MCA) stenosis degree and the brian blood supply. Methods PWI was performed in 30 patients with unilateral stenosis of MCA was diagnosed by HRMRI. The cerebral perfusion parameters including regional cerebral blood volume (rCBV) .regional cerebral blood flow(rCBF) .regional mean transit time(rMTT) and regional time to peak(rTTP) of the both cerebral hemispheres were quantitatively analysed. Results Among 30 patients, the MCA stenosis diagnosed by HRMRI as mild in 7, moderate in 9 and severe or acclusion in 14,respectively. Abnormal perfusion presented in all cases. The perfusion parameters (rCBF, rMTT and rTTP) had statistical significance. Between the rate of MCA moderate stenosis, severe stenosis or occlusion and the increase rate of rMTT showed a positive correlation(r=0. 897 and 0. 829 respectively,P<0. 01). Conclusion There is significantly value in evaluation of the MCA stenosis degree by HRMRI, which in combination with PWI to assess brain blood supply is of important value for clinic.%目的 探讨高分辨率MRI(high-resolution MRI,HRMRI)判定大脑中动脉(middle cerebral artery,MCA)狭窄程度与脑MRI灌注加权成像(perfusion weighted imaging,PWI)评价脑供血的价值.方法 对30例短暂性脑缺血(TIA)患者行HRMRI以判定单侧MCA狭窄程度,并行MRI PWI检查,得出患侧和镜像侧灌注参数,包括相对脑血容量(relative cerebral blood volume,rCBV)、相对脑血流量(relative cerebral blood flow,rBCF)、相对平均通过时间(relative mean transit time,rMTT)、相对达峰时间(relative time to peak,rTTP),并对其进行定量分析.结果 30例患者中,HRMRI判定MCA轻度狭窄7例,中度狭窄9例,重度狭窄或闭塞14例;30例灌注均出现异常,rCBF、rMTT、rTTP灌注参数均具有统计学意义,其中MCA中度、重度狭窄或闭塞组狭窄率与r

  4. Characteristics of Brain Perfusion in Patients of Parkinson's Disease

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Young Jin; Park, Min Jung; Kim, Jae Woo; Kang, Young Kang [Dong-A University College of Medicine, Busan (Korea, Republic of)

    2008-02-15

    It was well known that cerebral blood perfusion is normal or diffusely decreased in the majority of patients with Parkinson's disease (PD). Actually we interpreted brain perfusion SPECT images of PD patients in the clinical situation, we observed various cerebral perfusion patterns in patients with PD. So we performed brain perfusion SPECT to know the brain perfusion patterns of PD patients and the difference of perfusion patterns according to the sex and the age. Also we classified PD patients into small groups based on the brain perfusion pattern. Two hundred nineteen patients (M: 70, F: 149, mean age: 62.9{+-}6.9 y/o) who were diagnosed as PD without dementia clinically and 55 patients (M: 15, F: 40, mean age: 61.4{+-}9.2 y/o) as normal controls who had no past illness history were performed {sup 99m}Tc-HMPAO brain perfusion SPECT and neuropsychological test. At first, we compared all patients with PD and normal controls. Brain perfusion in left inferior frontal gyrus, left insula, left transverse temporal gyrus, left inferior parietal lobule, left superior parietal lobule, right precuneus, right caudate tail were lower in patients with PD than normal controls. Secondly, we compared male and female patients with PD and normal controls, respectively. Brain perfusion SPECT showed more decreased cerebral perfusion in left hemisphere than right side in both male and female patients compared to normal controls. And there was larger hypoperfusion area in female patients compared with male. Thirdly, we classified patients with PD and normal controls into 4 groups according to the age and compared brain perfusion respectively. In patient below fifties, brain perfusion in both occipitoparietal and left temporal lobe were lower in PD group. As the patients with PD grew older, hypoperfusion area were shown in both frontal, temporal and limbic lobes. Fourthly, We were able to divide patients into small groups based on cerebral perfusion pattern. There was normal

  5. An Experimental Model of Vasovagal Syncope Induces Cerebral Hypoperfusion and Fainting-Like Behavior in Awake Rats

    Science.gov (United States)

    McBride, Devin W.; Reis, Cesar; Frank, Ethan; Klebe, Damon W.; Zhang, John H.; Applegate, Richard

    2016-01-01

    Vasovagal syncope, a contributing factor to elderly falls, is the transient loss of consciousness caused by decreased cerebral perfusion. Vasovagal syncope is characterized by hypotension, bradycardia, and reduced cerebral blood flow, resulting in fatigue, altered coordination, and fainting. The purpose of this study is to develop an animal model which is similar to human vasovagal syncope and establish an awake animal model of vasovagal syncope. Male Sprague-Dawley rats were subjected to sinusoidal galvanic vestibular stimulation (sGVS). Blood pressure, heart rate, and cerebral blood flow were monitored before, during, and post-stimulation. sGVS resulted in hypotension, bradycardia, and decreased cerebral blood flow. One cohort of animals was subjected to sGVS while freely moving. sGVS in awake animals produced vasovagal syncope-like symptoms, including fatigue and uncoordinated movements; two animals experienced spontaneous falling. Another cohort of animals was preconditioned with isoflurane for several days before being subjected to sGVS. Isoflurane preconditioning before sGVS did not prevent sGVS-induced hypotension or bradycardia, yet isoflurane preconditioning attenuated sGVS-induced cerebral blood flow reduction. The sGVS rat model mimics elements of human vasovagal syncope pathophysiology (hypotension, bradycardia, and decreased cerebral perfusion), including behavioral symptoms such as fatigue and altered balance. This study indicates that the sGVS rat model is similar to human vasovagal syncope and that therapies directed at preventing cerebral hypoperfusion may decrease syncopal episodes and reduce injuries from syncopal falls. PMID:27658057

  6. Anxiety and cerebral blood flow during behavioral challenge. Dissociation of central from peripheral and subjective measures

    Energy Technology Data Exchange (ETDEWEB)

    Zohar, J.; Insel, T.R.; Berman, K.F.; Foa, E.B.; Hill, J.L.; Weinberger, D.R.

    1989-06-01

    To investigate the relationship between anxiety and regional cerebral blood flow, we administered behavioral challenges to 10 patients with obsessive-compulsive disorder while measuring regional cerebral blood flow with the xenon 133 inhalation technique. Each patient was studied under three conditions: relaxation, imaginal flooding, and in vivo (actual) exposure to the phobic stimulus. Subjective anxiety, obsessive-compulsive ratings, and autonomic measures (heart rate, blood pressure) increased significantly, but respiratory rate and PCO/sub 2/ did not change across the three conditions. Regional cerebral blood flow increased slightly (in the temporal region) during imaginal flooding, but decreased markedly in several cortical regions during in vivo exposure, when anxiety was highest by subjective and peripheral autonomic measures. These results demonstrate that intense anxiety can be associated with decreased rather than increased cortical perfusion and that ostensibly related states of anxiety (eg, anticipatory and obsessional anxiety) may be associated with opposite effects on regional cerebral blood flow.

  7. The guiding significance of the 640 layer CT perfusion combined with the vascular imaging in thrombolysis therapy for the super acute cerebral in-farction%640层CT灌注联合血管成像在脑梗死超早期溶栓中的指导意义

    Institute of Scientific and Technical Information of China (English)

    田峰; 田学实; 梁文胜

    2014-01-01

    Objective To investigate the guiding significance of 640 layer CT perfusion combined with vascular ima-ging in thrombolytic therapy for super acute cerebral infarction .Methods 30 cases of patients with superacute cere-bral infarction were taken the examination of brain CT scan and 640 CT layer perfusion combined with the vascular im-aging.The ischemic penumbra were determined according to the change of cerebral blood flow (CBF),regional cere-bral blood volume (rCBV),mean traverse time(MTT)and time to peak(TTP)in region of interest(ROI)and the ratio of left and right sides of CBF .At the same time ,38 patients were chosen to give thrombolytic therapy without CT perfu-sion imaging (20 patients with arterial thrombolytic therapy and 18 patients with intravenous thrombolytic therapy ) . Compare their discrepancy in efficacy .Results The effect of arteriovenous thrombolytic therapy guided by CT perfu-sion is better than that of non perfusion guidance of arteriovenous thrombolytic therapy .Conclusion It has a guid-ing significance in thrombolytic therapy for super acute cerebral infarction to make 640 CT perfusion combined with vascular imaging ,which can show that the degree of head and neck vascular stenosis and determine ischemic penumbra for guiding early clinical interventional thrombolytic therapy or vascular reconstruction treatment in order to save ische -mic penumbra and restore the blood perfusion of ischemic brain tissue as soon as possible .It has crucial clinical value to improve the prognosis and reduce the incidence of mortality and morbidity .%目的:探讨640层CT灌注联合血管成像在脑梗死超早期溶栓中的指导意义。方法对30例脑梗死超早期的患者,进行脑部CT平扫及640层CT灌注联合血管成像检查,根据脑血流量( CBF )、脑血容量、平均通过时间、达峰时间的变化及左右两侧CBF的比值,判定有无缺血半暗带;同时选择未做CT灌注检查的38例溶栓患者,对比它

  8. TLR4/NF-κB通路在深低温停循环逆行脑灌注技术脑保护机制中作用的研究%The role of TLR4/NF-κB pathway in cerebral protective effect of retrograde cerebral perfusion during deep ;hypothermic circulatory arrest

    Institute of Scientific and Technical Information of China (English)

    梁孟亚; 唐志贤; 陈光献; 荣健; 戴刚; 吴钟凯

    2013-01-01

    目的:研究TLR4/NF-κB通路是否参与深低温停循环逆行脑灌注的脑保护机制。方法五指山小型猪共10头,随机分成单纯深低温停循环组(DHCA组,n=5)与深低温停循环逆行脑灌注组(RCP组,n=5)。建立体外循环后,DHCA组降温至18℃后停循环40 min,RCP组停循环后经上腔静脉以10 ml/kg流量逆行脑灌注40 min。定期抽血检测血清IL-6水平。复灌180 min后处死动物取脑皮质组织行HE染色, Western blotting检测脑皮质TLR4,NF-κB/p65蛋白表达。结果脑皮质HE染色显示DHCA组较RCP组有更多炎症细胞浸润。在复灌60 min,复灌120 min及复灌180 min三个时点RCP的IL-6水平均显著低于DHCA组(t=7.314,P<0.01;t=5.172,P<0.01;t=4.676,P<0.01)。复灌180 min后RCP组脑皮质中TLR4水平明显低于DHCA组(t=10.212,P<0.001)。复灌180 min后RCP组脑皮质中NF-κB/p65水平明显低于DHCA组(t=3.344,P=0.011)。结论 RCP通过抑制TLR4/NF-κB信号通路而发挥抗炎作用,这可能是RCP脑保护作用的机制之一。%Objective To investigate whether TLR4/NF-κB Pathway is involved in cerebral protective effect of retrograde cerebral perfusion(RCP) during deep hypothermic circulatory arrest (DHCA). Methods Ten piglets of either sex (weigh 7.5-17.4 kg) were randomly assigned to 40 min of circulatory arrest (CA) at 18 ℃without cerebral perfusion (DHCA group, n=5) or RCP (RCP group, n=5). Blood samples were collected for assessment of serum IL-6 levels. After 3 h of reperfusion, cortical tissue was harvested for HE staining, western blotting of TLR4 and NF-κB/p65 expression. Results More severe inflammatory response was observed in brain tissue of DHCA group than RCP group. Serum IL-6 levels were significantly higher in the DHCA group than in RCP groups at 60 min, 120 min and 180 min after reperfusion (t=7.314, P<0.01; t=5.172,P<0.01; t=4.676, P<0.01 respectively). After 40 min of CA

  9. Metabolic pattern of the acute phase of subarachnoid hemorrhage in a novel porcine model: studies with cerebral microdialysis with high temporal resolution.

    Directory of Open Access Journals (Sweden)

    Christoffer Nyberg

    Full Text Available BACKGROUND: Aneurysmal subarachnoid hemorrhage (SAH may produce cerebral ischemia and systemic responses including stress. To study immediate cerebral and systemic changes in response to aneurysm rupture, animal models are needed. OBJECTIVE: To study early cerebral energy changes in an animal model. METHODS: Experimental SAH was induced in 11 pigs by autologous blood injection to the anterior skull base, with simultaneous control of intracranial and cerebral perfusion pressures. Intracerebral microdialysis was used to monitor concentrations of glucose, pyruvate and lactate. RESULTS: In nine of the pigs, a pattern of transient ischemia was produced, with a dramatic reduction of cerebral perfusion pressure soon after blood injection, associated with a quick glucose and pyruvate decrease. This was followed by a lactate increase and a delayed pyruvate increase, producing a marked but short elevation of the lactate/pyruvate ratio. Glucose, pyruvate, lactate and lactate/pyruvate ratio thereafter returned toward baseline. The two remaining pigs had a more severe metabolic reaction with glucose and pyruvate rapidly decreasing to undetectable levels while lactate increased and remained elevated, suggesting persisting ischemia. CONCLUSION: The animal model simulates the conditions of SAH not only by deposition of blood in the basal cisterns, but also creating the transient global ischemic impact of aneurysmal SAH. The metabolic cerebral changes suggest immediate transient substrate failure followed by hypermetabolism of glucose upon reperfusion. The model has features that resemble spontaneous bleeding, and is suitable for future research of the early cerebral and systemic responses to SAH that are difficult to study in humans.

  10. Staging of moyamoya disease by perfusion SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Kuwabara, Yasuo [Kyushu Univ., Fukuoka (Japan). Hospital; Matsushima, Toshio; Fukui, Masashi

    2001-04-01

    Staging of moyamoya disease, based on angiography and PET have already been established. The authors have established staging of moyamoya disease based on perfusion SPECT, that can be summarized as follows: Stage I, no abnormality is seen at rest or after acetazolamide loading; Stage II, no abnormality is seen at rest, however, a decreased response (blood flow increase rate: <15%) is seen to acetazolamide loading (a, a decreased response is seen only in the frontal lobe; b, a decreased response is seen in regions other than the frontal lobe; and c, a decreased response is seen throughout the cerebrum); Stage III, localized decrease in blood flow (blood flow decrease compared with peripheral tissue: {>=}15%) and marked decrease in response to acetazolamide (blood flow increase rate: <5%) are seen at rest. In Stage III, CT and MRI show no abnormal findings or only mild lesions of the white matter; and Stage IV, multiple decreases in blood flow are seen at rest, and CT and MRI reveal infarctions and severe atrophy at the same sites. The above staging does not require determination of cerebral blood flow, and thus it can be used in children, in whom cerebral blood flow determination is difficult. The authors performed 99m-Tc ECD perfusion SPECT in 25 patients with moyamoya disease for the staging, and compared staging based on angiography with staging based on perfusion SPECT. The results did not show a correlation between the 2 staging methods. A problem inherent in the staging of moyamoya disease based on perfusion SPECT is that the relationship between cerebral blood flow and cerebral radioactivity concentrations may differ depending on the drug used to determine cerebral blood flow. Thus, although the present staging system does not depend on any specific radioactive drug to determine cerebral blood flow, further investigation is necessary to identify a more appropriate drug than those in current use. (K.H.)

  11. 甲亢患者人格特征及与脑血流灌注相关分析%The Study of Personality Traits and its Relationship to Cerebral Blood Flow Perfusion in Patients with Hyperthyroidism

    Institute of Scientific and Technical Information of China (English)

    修雁; 王建华; 虞一萍; 石洪成; 顾宇参; 胡鹏程; 刘文官; 陈雪芬; 陈曙光; 余浩军; 陈可靖

    2011-01-01

    Objective:To analyze the personality traits of patients with hyperthyroidism and its possible relationship to cerebral blood flow. Methods: Thirty-five patients (9 males, 26 females; 38. 74 ± 10. 57 ys) with hyperthyroidism were enrolled, who were divided into short duration group(equal or less 6 months,n= 15) and long duration group (longer than 6 months,n- 20). Twenty-eight healthy volunteers (males 8,females 20; 35. 8 ± 9. 41ys) were included as controls. SPECT cerebral blood flow perfusion imaging was performed at rest after 99Tcm- ECD injection. The personality traits of all patients and controls were assessed with EPQ questionnaire. Results: Hypoperfusion in limb system and frontal lobes were shown in hyperthyroidism patients. Hyperthyroidism patients had higher neuroticism and psychoticism scores, which had not changed significantly after eu-thyroid. The scores of neuroticism were correlated negatively with rCBF in thalamus, parahippocampal gyrus, posterior ento-rhinal cortex, globus pallidus and mammilary body(P<0. 05). Conclusions: Patients with hyperthyroidism have significant neuroticism and psychoticism characteristics, which might be related to impaired cerebral blood flow in specific region, besides their specific personality traits.%目的:分析甲亢患者人格特征及与脑功能变化的关系.方法:35例甲亢患者纳入研究,男性9例,女性26例;平均年龄(38.74±10.57)岁;病程为1.5个月至9年.短病程组15例(病程小于等于6个月),长病程组20例(病程大于6个月).正常对照者28例,男性8例,女性20例;平均年龄(35.8±9.41)岁.所有患者及正常对照均行静息99Tcm-ECD SPECT脑血流灌注显像.应用艾森克人格问卷(EPQ)分析人格特征;7例患者经治疗甲功正常后再次行人格特征分析及脑血流灌注显像.结果:甲亢患者具有高神经质及精神质的人格特征(P<0.05);不同病程患者人格特征无显著差异;治疗后患者人格

  12. A combined study of cerebral artery system through super-selective angiography and real-time-colored latex perfusion in rabbits%超选择造影与实时乳胶灌注在兔脑动脉系统研究应用

    Institute of Scientific and Technical Information of China (English)

    张桂运; 陈左权; 凌锋; 海舰; 李玉健; 顾斌贤; 吴春红; 俞丽敏

    2009-01-01

    Objective To study the character of cerebral artery system in rabbits and to found the base for establishing cerebrovascular disease models of rabbits.Methods Microcatheter-technique was used to perform super-selective cerebral angiography in New Zealand rabbits,after which three dimensional vascular reconstructions were adopted.At the end of angiography,the live rabbits,through microcatheter,were real time perfused with colored latex mixed with contrast medium under fluoroscopy for visualization of their cerebrovascular anatomy.Results The arteries above aortic arch and the arterial system in anterior and posterior circulation were clearly visualized.After latex perfusion,the arterial circle of skull base,anterior cerebral arteries,middle cerebral arteries,posterior cerebral arteries and their subpial branches were clearly displayed as well asthe resistance vessels in posterior watershed.Conclusions Super-selective cerebral angiography was helpful to better display the anterior and posterior circulation in rabbits,and the colored latex perfusion could provide more details about the microcirculation especially in the posterior watershed.The outcome of colored latex perfusion could be used as an authentication to angiography.With the combination of super-selective angiography and colored latex perfusion,it was easy to find the morphological changes of cerebral arterial circulation in rabbits.%目的 研究兔脑动脉系统的特点,为建立兔脑血管疾病模型奠定基础.方法 应用微导管技术对新西兰大白兔进行超选择性脑血管造影并进行血管三维重建,造影完毕后在活体上透视下经微导管进行染色乳胶实时灌注.结果 主动脉弓上血管及颅内前后循环系统显影清楚;乳胶灌注后清晰显示颅底动脉环、大脑前动脉、大脑中动脉、大脑后动脉及其皮层分枝,后分水岭区阻力血管显示清楚.结论 超选择性脑血管造影有利于更好地显示兔脑前后动脉系统,

  13. Antegrade Versus Retrograde Cerebral Perfusion in Relation to Postoperative Complications Following Aortic Arch Surgery for Acute Aortic Dissection Type A%双侧顺行与上腔逆行脑灌注在A型主动脉夹层中应用效果对比的临床研究

    Institute of Scientific and Technical Information of China (English)

    吴智勇; 王志维; 夏军; 张遵严; 陈雪芬; 邓宏平; 徐鹏; 李罗成; 王杰

    2011-01-01

    Objective Antegrade or retrograde cerebral perfusion ( RCP) , is a well - established method of brain protection in aortic arch surgery. In this retrospective study, we compard the two methods of brain perfusion. Methods From Oct 2008 to Jan 2011,63 consecutive patients were urgently operated for acute type A aortic dissection and underwent arch replacement under deep hypothermic circulatory arrest (DHCA). Our patient cohort was divided into those protected with antegrade cerebral perfusion ( ACP) (group A, n = 54) and those protected with RCP (group B, n = 9). Results There was no siguificant difference in operative time, cardiopulmonary bypass - time, myocardial blocking time, cerebral - perfusion time between groups B and A, but the incidence of temporary neurologic dysfunction, the mean extubation time,the mean ICU -stay,the hospital -stay increased. Conclusion The antegrade perfusion was related with significantly lower incidence of temporary neurological complications, earlier extubation, shorter ICU - stay, and hospitalization.%目的 深低温停循环(DHCA)的同时顺行或逆行脑灌注,是一种行之有效的脑保护方法.在这个回顾性研究中,我们比较顺行、逆行两种方法的临床疗效.方法 从2008年10月~2011年1月,63例患者行Stanford A型主动脉夹层手术,均在深低温停循环下行全弓置换.其中选择双侧顺行脑灌注的A组病人54例,B组采用上腔静脉逆灌(RCP)脑保护的病人9例.结果 B组与A组比较在手术时间、体外循环时间、心肌阻断时间、脑灌注时间差异不明显,而B组短暂脑神经功能障碍发生率、拔管时间、ICU滞留时间、住院时间有所增加.结论 顺行脑灌注较上腔逆灌降低短暂脑神经功能障碍发生率从而拔管早,缩短ICU及住院时间.

  14. Management of raised intracranial pressure in children with traumatic brain injury

    OpenAIRE

    Vinay Kukreti; Hadi Mohseni-Bod; James Drake

    2014-01-01

    Increased intracranial pressure (ICP) is associated with worse outcome after traumatic brain injury (TBI). The current guidelines and management strategies are aimed at maintaining adequate cerebral perfusion pressure and treating elevated ICP. Despite controversies, ICP monitoring is important particularly after severe TBI to guide treatment and in developed countries is accepted as a standard of care. We provide a narrative review of the recent evidence for the use of ICP monitoring and man...

  15. The effect of water immersion during exercise on cerebral blood flow.

    NARCIS (Netherlands)

    Pugh, C.J.; Sprung, V.S.; Ono, K.; Spence, A.L.; Thijssen, D.H.J.; Carter, H.H.; Green, D.J.

    2015-01-01

    INTRODUCTION: Regular exercise induces recurrent increases in cerebrovascular perfusion. In peripheral arteries, such episodic increases in perfusion are responsible for improvement in arterial function and health. We examined the hypothesis that exercise during immersion augments cerebral blood flo

  16. Cerebral Autoregulation in Normal Pregnancy and Preeclampsia

    NARCIS (Netherlands)

    van Veen, Teelkien R.; Panerai, Ronney B.; Haeri, Sina; Griffioen, Annemiek C.; Zeeman, Gerda; Belfort, Michael A.

    2013-01-01

    OBJECTIVE: To test the hypothesis that preeclampsia is associated with impaired dynamic cerebral autoregulation. METHODS: In a prospective cohort analysis, cerebral blood flow velocity of the middle cerebral artery (determined by transcranial Doppler), blood pressure (determined by noninvasive arter

  17. 脑灌注显像剂99Tcm-MPBDA的研制与动物实验%Preparation and animal studies of a novel potential cerebral perfusion imaging agent

    Institute of Scientific and Technical Information of China (English)

    王荣福; 张春丽; 朱绍莉; 苗玉斌; 唐志刚; 刘伯里

    2001-01-01

    目的研制一种新的SPECT脑灌注显像剂。方法将化学合成的N2S三齿配体2-巯基丙基-1,2-苯二胺(MPBDA)用99Tcm标记;25只昆明种小白鼠静脉注射100 μL 555~740 kBq 99Tcm-MPBDA,进行体内生物分布实验;2只健康恒河猴(4~6 kg)静脉快速注入218.3~333 MBq 99Tcm-MPBDA或99Tcm-双半胱乙脂(ECD)后分别即刻连续动态采集和给药后70 min行全身显像和脑断层显像;2组小鼠和3只家兔分别进行了急性毒理和热原实验。结果 99Tcm-MPBDA的产率和放化纯度分别大于95%和97%。小鼠体内分布实验结果表明99Tcm-MPBDA能在脑内浓聚并具有很好的脑滞留,血清除半衰期小于15 min。猴脑动态血流灌注显像示注药后2 min脑放射性达高峰,1 h脑放射性占2 min的83.0%,70 min后入脑量高达2.76%ID,略低于99Tcm-ECD(2.9%ID)。断层显像可见大脑灰白质对比度好,影像轮廓较清晰。小鼠和兔子注射99Tcm-MPBDA后均无毒副反应。结论研制的99Tcm-MPBDA具有与99Tcm-ECD相近的脑血流灌注显像性能,用于活体安全可靠。%Objective To investigate a novel potential SPECT cerebral blood flow perfusion imaging agent. Methods N2S tridentated α-mercapto-propyl-1,2-benzenediamine (MPBDA) was obtained from chemical synthesis IR and was labeled with 99Tcm.Biodistribution analysis in 25 mice was performed after intravenous injection of 100 μL 555~740 kBq of 99Tcm-MPBDA. Dynamic acquisition was performed after rapid intravenoues injection of 218.3~333 MBq 99Tcm-MPBDA or 99Tcm-ECD,while whole body imaging and brain perfusion imaging were done after 70 min in 2 normal monkeys.Preclinical studies including toxicity and pyrogen tests in mice and rabbits were undertaken.Results The radiochemical synthetic yield and radiochemical purity of MPBDA labeled with 99Tcm were more than 95% and 97%, respectively. Mice biodistribution test showed the 99Tcm-MPBDA can concentrate in brain with good retention

  18. Dynamic cerebral autoregulatory capacity is affected early in Type 2 diabetes

    DEFF Research Database (Denmark)

    Kim, Y.S.; Immink, R.V.; Stok, W.J.;

    2008-01-01

    ) and impaired in subjects with DM+ (30+/-5 degrees ; Pblood pressure oscillations by affected dynamic cerebral autoregulation. The steady-state response of MCA V(mean) to postural change was comparable for all groups (-12+/-6% in CTRL subjects......, -15+/-6% in subjects with DM- and -15+/-7% in subjects with DM+). HbA(1c) (glycated haemoglobin) and the duration of diabetes, but not blood pressure, were determinants of transfer function phase. In conclusion, dysfunction of dynamic cerebral autoregulation in subjects with Type 2 diabetes appears......Type 2 diabetes is associated with an increased risk of endothelial dysfunction and microvascular complications with impaired autoregulation of tissue perfusion. Both microvascular disease and cardiovascular autonomic neuropathy may affect cerebral autoregulation. In the present study, we tested...

  19. Perfusion CT in acute stroke; Stellenwert der CT-Perfusion fuer die Therapie des Schlaganfalls

    Energy Technology Data Exchange (ETDEWEB)

    Eckert, Bernd [Asklepios Klinik Altona (Germany). Radiologie und Neuroradiologie; Roether, Joachim [Asklepios Klinik Altona (Germany). Neurologische Abt.; Fiehler, Jens [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Klinik und Poliklinik fuer Neuroradiologische Diagnostik und Intervention; Thomalla, Goetz [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Klinik und Poliklinik fuer Neurologie, Kopf- und Neurozentrum

    2015-06-15

    Modern multislice CT scanners enable multimodal protocols including non-enhanced CT, CT angiography, and CT perfusion. A 64-slice CT scanner provides 4-cm coverage. To cover the whole brain, a 128 - 256-slice scanner is needed. The use of perfusion CT requires an optimized scan protocol in order to reduce exposure to radiation. As compared to non-enhanced CT and CT angiography, the use of CT perfusion increases detection rates of cerebral ischemia, especially small cortical ischemic lesions, while the detection of lacunar and infratentorial stroke lesions remains limited. Perfusion CT enables estimation of collateral flow in acute occlusion of large intra- or extracranial arteries. Currently, no established reliable thresholds are available for determining infarct core and penumbral tissue by CT perfusion. Moreover, perfusion parameters depend on the processing algorithms and the software used for calculation. However, a number of studies point towards a reduction of cerebral blood volume (CBV) below 2 ml/100 g as a critical threshold that identifies infarct core. Large CBV lesions are associated with poor outcome even in the context of recanalization. The extent of early ischemic signs on non-enhanced CT remains the main parameter from CT imaging to guide acute reperfusion treatment. Nevertheless, perfusion CT increases diagnostic and therapeutic certainty in the acute setting. Similar to stroke MRI, perfusion CT enables the identification of tissue at risk of infarction by the mismatch between infarct core and the larger area of critical hypoperfusion. Further insights into the validity of perfusion parameters are expected from ongoing trials of mechanical thrombectomy in stroke.

  20. 双源CT全脑灌注对短暂性脑缺血发作脑血流动力学变化的评价%The evaluation of cerebral hemodynamic changes of transient ischemic attack in dual source CT perfusion

    Institute of Scientific and Technical Information of China (English)

    卞力勇

    2015-01-01

    Objective To explore cerebral hemodynamic changes of transient ischemic attack(TIA)in dual source CT perfusion(CTP). Method Twenty patients with suspected TIA underwent plain CT and CTP within 24h of the onset of symptoms. The results of the abnormal regions of the cerebral blood flow and the contralatcral normal region were comparatively analyzed. Result Lacunar infarction were found in 15 out of 20 patients who were all with abnormal perfusion area. The imaging results demonstrated that significantly larger time to peak(TTP) delay in 20 patients with abnormal perfusion area was found compared with that in contralateral normal region(P 0.05),and no significant change of cerebral blood flow(CBF) was found.Conclusion CTP with dual source CT can accurately display cerebral hemodynamic changes of transient ischemic attack(TIA) and provides objective evidence for early diagnosis and treatment.%目的:探讨双源CT全脑灌注对短暂性脑缺血发作(transient ischemic attack, TIA)血流动力学改变的临床价值。方法临床拟诊TIA患者20例,均在症状出现24小时内行头颅CT平扫及CT Perfusion检查,将脑血流异常区与健侧对应区的情况做对比分析。结果20例患者中,15例患者出现腔梗改变。20例患者均出现灌注异常区,患侧达峰时间(time to peak,TTP)时间较健侧明显延长(P0.05),所有患者脑血流量(cerebral blood flow,CBF)无明显改变。结论双源CT全脑灌注能较好地反映TIA脑血流动力学变化,为早期诊断、治疗提供客观依据。

  1. The effect of CO sub 2 on pulmonary artery pressure (P sub pa ) over time in the isolated perfused rabbit lung

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, P.; Shayevitz, J. (Univ. of Michigan, Ann Arbor (United States))

    1991-03-11

    The isolated perfused rabbit lung model is used in studies of pulmonary hemodynamics, structure, and function under conditions closely resembling those which occur in living animals. The purpose of this study is to observe changes in P{sub pa} in response to differing concentrations of CO{sub 2} over time. After rapid exsanguination a tracheostomy was performed. Cannulas were secured in the main pulmonary artery and the left atrium. The lungs were perfused with Krebs-Henseleit buffer mixed with blood at a rate of 120 ml/min with recirculation. The temperature of the perfusate was maintained between 35 and 38C. The lungs were then ventilated with 5% CO{sub 2} in air with a tidal volume of 10 ml/kg at 20 breaths/min. CO{sub 2} was altered randomly by ventilating the lungs 2, 5 or 10% CO{sub 2} in air. Metabolic acidosis was corrected with NaHCO{sub 3}. In the first two hour period after lung perfusion was begun, the model was allowed to stabilize at each CO{sub 2} concentration, and pH, pCO{sub 2}, pO{sub 2}, and base excess were determined at each P{sub pa}. All measurements were repeated in the second period beginning two hours after lung perfusion was started. P{sub pa} was plotted against pH for each animal in both early and late phases, and simple regression analysis was performed. The slopes and the y intercepts for the data sets in both groups were compared using one factor ANOVA, and were found to be significantly different, implying a statistical difference between regression lines. In the early phase this model behaves like the in vivo lung, i.e. hypercarbia appears to increase, while hypocarbia decreases, P{sub pa}. During the late phase of lung perfusion the opposite occurs.

  2. Tomographic cerebral blood flow measurement during carotid surgery

    DEFF Research Database (Denmark)

    Rathenborg, Lisbet Knudsen; Vorstrup, Sidsel; Olsen, K S

    1994-01-01

    OBJECTIVES: The aim of the study was to depict regional cerebral blood flow (rCBF) during carotid cross clamping using 99mTechnetium-hexamethylpropylene amine oxime (TcHMPAO). This tracer rapidly passes the blood-brain barrier and is retained for hours in the brain tissue. Injecting TcHMPAO during...... RESULTS: We found a significant correlation between stump pressure and enhancement of side-to-side asymmetry in rCBF due to carotid cross clamping. Pronounced variations were seen in which regions were deprived of perfusion during clamping. CONCLUSION: TcHMPAO allows tomographic assessment of CBF during...

  3. Electroacupuncture acutely improves cerebral blood flow and attenuates moderate ischemic injury via an endothelial mechanism in mice.

    Directory of Open Access Journals (Sweden)

    Ji Hyun Kim

    Full Text Available Electroacupuncture (EA is a novel therapy based on traditional acupuncture combined with modern eletrotherapy that is currently being investigated as a treatment for acute ischemic stroke. Here, we studied whether acute EA stimulation improves tissue and functional outcome following experimentally induced cerebral ischemia in mice. We hypothesized that endothelial nitric oxide synthase (eNOS-mediated perfusion augmentation was related to the beneficial effects of EA by interventions in acute ischemic injury. EA stimulation at Baihui (GV20 and Dazhui (GV14 increased cerebral perfusion in the cerebral cortex, which was suppressed in eNOS KO, but there was no mean arterial blood pressure (MABP response. The increased perfusion elicited by EA were completely abolished by a muscarinic acetylcholine receptor (mAChR blocker (atropine, but not a β-adrenergic receptor blocker (propranolol, an α-adrenergic receptor blocker (phentolamine, or a nicotinic acetylcholine receptor (nAChR blocker (mecamylamine. In addition, EA increased acetylcholine (ACh release and mAChR M3 expression in the cerebral cortex. Acute EA stimulation after occlusion significantly reduced infarct volume by 34.5% when compared to a control group of mice at 24 h after 60 min-middle cerebral artery occlusion (MCAO (moderate ischemic injury, but not 90-min MCAO (severe ischemic injury. Furthermore, the impact of EA on moderate ischemic injury was totally abolished in eNOS KO. Consistent with a smaller infarct size, acute EA stimulation led to prominent improvement of neurological function and vestibule-motor function. Our results suggest that acute EA stimulation after moderate focal cerebral ischemia, but not severe ischemia improves tissue and functional recovery and ACh/eNOS-mediated perfusion augmentation might be related to these beneficial effects of EA by interventions in acute ischemic injury.

  4. 停循环和局部脑灌在主动脉弓中断手术中的应用%The usefulness of deep hypothermic circulatory arrest and regional cerebral perfusion in interrupted aortic arch

    Institute of Scientific and Technical Information of China (English)

    郭铮; 王伟; 张蔚; 沈佳; 唐嘉忠; 朱德明

    2013-01-01

    Objective To evaluate the effects of deep hypothermic circulatory arrest (DHCA) and regional cerebral perfusion (RCP) in interrupted aortic arch (IAA) corrective surgery.Methods Thirty-one infants younger than 3-month-old with IAA were undergone corrective surgery with DHCA or RCP.The bypass time,aortic clamp time,DHCA or RCP time,hematocrit,ventilation time,ICU stay time and post-operative complications were recorded and compared between two groups.Results The bypass time,aortic clamp time were longer in RCP group,and the RCP time was longer than DHCA time.One postoperative death and two neurological complications took place in DHCA group,while no mortality and neurological complications in RCP group.There were no significant differences in mortality and morbidity between two groups.Conclusion Because complicated surgery is undergone in IAA corrective procedure,RCP technique is safer to protect the brain function.%目的 比较深低温停循环(DHCA)与局部低流量脑灌(RCP)在小儿主动脉弓中断(IAA)纠治手术中的应用效果.方法 总结31例3个月以下的IAA合并室间隔缺损、房间隔缺损的婴儿手术病例,分为DHCA和RCP两组不同的体外循环方式,对术中转流时间,阻断时间,红细胞比容,停循环或脑灌时间,呼吸机插管时间,ICU滞留时间,术后低心排出量,肾功能衰竭,肺部炎症,出凝血障碍,多器官功能障碍,神经系统并发症,院内死亡率等情况进行分析.结果 RCP组手术的体外循环时间,阻断时间及脑灌时间显著长于DHCA组.DHCA组患儿死亡1例,神经系统并发症2例,RCP组无死亡和神经系统并发症,但两组无统计学差异.结论 IAA手术需要较长时间在主动脉上进行操作,采用RCP技术可以更好的保护神经系统功能,减少并发症.

  5. Accuracy of MR perfusion weighted imaging for cerebral glioma grading: a meta-analysis%磁共振灌注成像对胶质瘤良恶性分级的荟萃分析

    Institute of Scientific and Technical Information of China (English)

    闵志刚; 刘红娟; 李敏; 刘丽华; 金晨旺; 张明

    2010-01-01

    Objective To evaluate values of MR perfusion weighted imaging(PWI)in the grading of intracranial gliomas by a meta-analysis. Methods All English and Chinese literatures published before November 2009 in PUBMED and CNKI(China National Knowledge Infrastructure)were searched.Literature searching requirements:(1)MR PWI with region of interest(ROI)must have been applied in the grading of gliomas;(2)histopathological results must have been used as the reference standards. In addition, after data extraction, a bivariate random-effect model and hierarchical weighted symmetric summary receiver-operating curve must have been utilized to pool the data. Furthermore, a meta regression method must have been applied to detect and analyze the factors that affected the diagnostic accuracy. Results Overall, fourteen studies were included with a total amount of 1021 patients. The pooled sensitivity,specificity and diagnostic odds ratio with 95% of CI were 93%(89%-96%), 81%(73%-87%)and 55(28-107), respectively. The factors that affected the diagnostic accuracy were the sample size, the ratio of malignant glioma, the injection rate of contrast agents, the repetition time and the cutoff value.Heterogeneity did exist among the results obtained from different studies. Conclusion the relative cerebral blood volume(rCBV)of MR PWI can be referred to differentiate malignant cerebral gliomas from benign ones with sound sensitivity and specificity. However, there is not a unified threshold applied in the researches that have been conducted so far, and techniques used differ among the studies. In summary,clinical application values of rCBV of MR PWI are to be corroborated by further studies with a larger sample size.%目的 采用荟萃(Meta)分析方法评价磁共振灌注成像在胶质瘤分级中的价值.方法 检索PUBMED数据库、CNKI(中国知网)系列数据库2009年11月前国内外公开发表的所有中英文文献,要求:(1)采用磁共振灌注成像对

  6. 丁苯酞对脑小血管病患者血流灌注及认知功能影响的临床研究%Effects of Dl-3-n-butylphthalide on cerebral perfusion and cognitive function in patients with cerebral small vessel disease

    Institute of Scientific and Technical Information of China (English)

    贾朝均; 罗丽君; 余巨明; 王莉; 周睿娇

    2016-01-01

    目的:探讨丁苯酞对脑小血管病患者认知功能及脑血流灌注的影响。方法将经知情同意及医院医学伦理委员会审查,并符合入组条件的70例脑小血管病患者随机分为常规治疗组(A 组)18例、丁苯酞组(B 组)26例及尼莫地平组(C 组)26例,疗程1个月。治疗前后作蒙特利尔量表(MOCA)评分。B 组及 C 组各随机选取10例患者于治疗前后行64排螺旋 CT 灌注成像检查,计算灌注参数值变化,并对疗效进行评定。结果68例患者最终完成实验。(1)MOCA 总评分变化:①B 组及 C 组治疗后 MOCA 评分较治疗前明显改善(均 P<0.01);②B 组与 C 组治疗后 MOCA 评分较 A 组治疗后均显著改善(均 P<0.05);但 B 组与 C 组 MOCA 总评分比较无统计学差异(P>0.05)。(2)MOCA 亚项评分变化:B 组治疗后在视空间及执行力、注意力及计算力、语言、延迟记忆力和抽象评分的变化有显著性差异(均 P<0.05);C 组治疗后在视空间及执行力、注意力及计算力、语言和延迟记忆力评分的变化有统计学差异(均 P<0.05);B 组治疗后在延迟记忆力亚项评分较 C 组治疗后变化更明显,差异有统计学意义(P<0.05)。(3)基底节区层面灌注成像参数变化比较:B 组及 C 组治疗后脑血流速度(CBF)、脑血流量(CBV)及平均通过时间(MTT)较治疗前均明显改善(P<0.01)。但 B 组与 C 组比较无统计学差异(P>0.05)。结论丁苯酞软胶囊可改善脑小血管病患者的认知功能,尤其是记忆力、视空间执行能力和计算力,并能提高局部脑灌注量,其作用至少不弱于尼莫地平片,且安全无明显不良反应。%Objective To investigate the impact of Dl-3-n-butylphthalide on the local cerebral perfusion and cognitive function in patients with cerebral small vessel disease. Methods 70 patents with cerebral

  7. Associations of sedentary behaviour, physical activity, blood pressure and anthropometric measures with cardiorespiratory fitness in children with cerebral palsy.

    Directory of Open Access Journals (Sweden)

    Jennifer M Ryan

    Full Text Available Children with cerebral palsy (CP have poor cardiorespiratory fitness in comparison to their peers with typical development, which may be due to low levels of physical activity. Poor cardiorespiratory fitness may contribute to increased cardiometabolic risk.The aim of this study was to determine the association between sedentary behaviour, physical activity and cardiorespiratory fitness in children with CP. An objective was to determine the association between cardiorespiratory fitness, anthropometric measures and blood pressure in children with CP.This study included 55 ambulatory children with CP [mean (SD age 11.3 (0.2 yr, range 6-17 yr; Gross Motor Function Classification System (GMFCS levels I and II]. Anthropometric measures (BMI, waist circumference and waist-height ratio and blood pressure were taken. Cardiorespiratory fitness was measured using a 10 m shuttle run test. Children were classified as low, middle and high fitness according to level achieved on the test using reference curves. Physical activity was measured by accelerometry over 7 days. In addition to total activity, time in sedentary behaviour and light, moderate, vigorous, and sustained moderate-to-vigorous activity (≥10 min bouts were calculated.Multiple regression analyses revealed that vigorous activity (β = 0.339, p<0.01, sustained moderate-to-vigorous activity (β = 0.250, p<0.05 and total activity (β = 0.238, p<0.05 were associated with level achieved on the shuttle run test after adjustment for age, sex and GMFCS level. Children with high fitness spent more time in vigorous activity than children with middle fitness (p<0.05. Shuttle run test level was negatively associated with BMI (r2 = -0.451, p<0.01, waist circumference (r2 = -0.560, p<0.001, waist-height ratio (r2 = -0.560, p<0.001 and systolic blood pressure (r2 = -0.306, p<0.05 after adjustment for age, sex and GMFCS level.Participation in physical activity, particularly at a vigorous intensity, is

  8. Cerebral vascular effects of loading dose of dexmedetomidine: A Transcranial Color Doppler study

    Directory of Open Access Journals (Sweden)

    Appavoo Arulvelan

    2016-01-01

    Full Text Available Background: Dexmedetomidine has been widely used in critical care settings because of its property of maintaining stable hemodynamics and inducing conscious sedation. The use of dexmedetomidine is in increasing trend particularly in patients with neurological disorders. Very few studies have focused on the cerebral hemodynamic effects of dexmedetomidine. This study is aimed to address this issue. Methods: Thirty patients without any intracranial pathology were included in this study. Middle cerebral artery flow velocity obtained from transcranial color Doppler was used to assess the cerebral hemodynamic indices. Mean flow velocity (mFV, pulsatility index (PI, cerebral vascular resistant index (CVRi, estimated cerebral perfusion pressure (eCPP, and zero flow pressure (ZFP were calculated bilaterally at baseline and after infusion of injection Dexmedetomidine 1 mcg/Kg over 10 min. Results: Twenty-six patients completed the study protocol. After administration of loading dose of dexmedetomidine, mFV and eCPP values were significantly decreased in both hemispheres (P < 0.05; PI, CVRi, and ZFP values showed significant increase (P < 0.05 after dexmedetomidine infusion. Conclusion: Increase in PI, CVRi, and ZFP suggests that there is a possibility of an increase in distal cerebral vascular resistance (CVR with loading dose of dexmedetomidine. Decrease in mFV and eCPP along with an increase in CVR may lead to a decrease in cerebral perfusion. This effect can be exaggerated in patients with preexisting neurological illness. Further studies are needed to evaluate the effect of dexmedetomidine on various other pathological conditions involving brain like traumatic brain injury and vascular malformations.

  9. 应用单光子发射断层显像评价合并大脑后动脉病变的烟雾病患者脑血流灌注%Evaluation of cerebral perfusion in moyamoya diseased patients with posterior cerebral artery lesions by single photon emission tomography examination

    Institute of Scientific and Technical Information of China (English)

    王莉; 段炼; 杨伟中; 龙亚红; 暴向阳; 赵峰; 咸鹏

    2013-01-01

    目的 分析合并大脑后动脉(PCA)病变的烟雾病患者脑血流异常灌注情况.方法 共纳入27例合并PCA病变的烟雾病患者,根据DSA检查结果,判定27例患者54侧的半球的铃木分期,及54支PCA的病变程度.27例患者均接受单光子发射断层显像术(SPECT)检查,记录额叶、顶叶、颞叶、枕叶、基底核区3~4个感兴趣区的平均局部脑血流量(rCBF),用各个脑区rCBF与小脑的rCBF的比值作为各个脑区rCBF的相对值.判定PCA病变程度、不同铃木分期对各脑叶rCBF相对值的影响. 结果 ①随着PCA病变程度的加重,额叶、顶叶、颞叶、枕叶、基底核区的rCBF相对值均逐渐下降,差异具有统计学意义,均P<0.05;其中顶叶轻度PCA病变的rCBF相对值(74±6)高于中度(63±9)、重度病变(60±17) PCA的rCBF相对值,差异有统计学意义;枕叶轻度PCA病变的rCBF相对值(72±7)高于中度(65±9)、重度病变(60±15) PCA的rCBF相对值,差异有统计学意义.②不同铃木分期的额叶、顶叶、颞叶、枕叶、基底核区rCBF相对值比较,差异均无统计学意义,P>0.05. 结论 各脑叶的rCBF相对值随着PCA病变程度加重而下降,但与铃木分期的病变程度无关.脑血管后循环病变可能是影响烟雾病患者脑血流灌注水平的重要因素.%Objective To analyze the abnormal cerebral blood flow perfusion in moyamoya diseased patients with posterior cerebral artery ( PCA) lesions. Methods A total of 27 moyamoya diseased patients with posterior cerebral artery lesions were enrolled in the study. According to the digital subtract an-giography (DSA) results, the Suzuki s stages of 27 patients ( 54 hemispheres) were determined and the PCA grading in all the 27 patients were identified. All the patients accepted single photon emission tomography ( SPECT) examination, and the mean value of three or four regions of interest was calculated in five regions ( frontal, parietal, temporal, and occipital

  10. Pulmonary ventilation/perfusion scan

    Science.gov (United States)

    V/Q scan; Ventilation/perfusion scan; Lung ventilation/perfusion scan ... A pulmonary ventilation/perfusion scan is actually two tests. They may be done separately or together. During the perfusion scan, a health care provider injects ...

  11. 血压与出血性脑梗死预后的关系探讨%Relationships between blood pressure and hemorrhagic cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    邱金华; 刘红英; 蔡春生

    2011-01-01

    Objective To explore the relationship between blood pressure and hemorrhagic cerebral infarction. Methods Retrospectively reviewed clinical data of 242 patients with acute cerebral infarction, then all patients with hemorrhagic cerebral infarction were selected. The distributions of different level of blood pressure (>180/110mm Hg;90/70~180/110mm Hg;<90/70mm Hg) were compared between the patients with or without hemorrhagic cerebral infarction, as the same, different prognosis were compared among the patients with hemorrhagic cerebral infarction based on the different level of blood pressure. Results Of the total patients with acute cerebral infarction,4. 1%(10) presented with blood pressure<90/70mm Hg,88. 0%(213) with blood pressure 90/70~180/110mm Hg and 7.9%(19) with blood pressure>180/110mm Hg. In all the patients,20 cases(8. 3%) with hemorrhagic cerebral infarction,among which,60.0%(12) patients with blood pressure>180/110mm Hg and with 7 cases died, 10.0%(2) patients with blood pressure<90/70mm Hg and with 1 case died,30.0%(6) patients with blood pressure 90/70~180/110mm Hg and with 2 cases died. The distribution of patients with blood pressure>180/110mm Hg in those two type of cerebral infraction were statistically significant (P=0. 000) ,the ratio seemed higher in patients with hemorrhagic cerebral infarction, and among the patients with hemorrhagic cerebral infarction, the distribution of prognosis were the same statistically significant based on the diffetent level of blood pressure, among which, patients with blood pressure>180/110mm Hg(P =0.041) or<90/70mm Hg(P =0.037) seemed like to have a higher mortality. Conclusion Severe high blood pressure(>180/110mm Hg) should be one of the high risk factors for patients with hemorrhagic cerebral infarction,when blood pressure>180/110 mm Hg or <90/70mm Hg happened in the pathogenesis, patients always be with poor outcome. So, making proper control strategy of blood pressure for

  12. A new type of discrepancy between cerebral blood flow measured with {sup 133}Xe and HmPAO-{sup 99}Tc perfusion; Discordances entre la mesure du debit sanguin cerebral au xenon 133 et de la perfusion cerebrale au HmPAO {sup 99m}Tc: un nouveau cas de figure

    Energy Technology Data Exchange (ETDEWEB)

    Steinling, M.; Amegassi, F.; Mazingue, A.; Rousseaux, M. [Centre Hospitalier Universitaire, 59 - Lille (France)

    2000-09-01

    We report a clinical case of a new type of discrepancy between two tracers usable for brain functional imaging: the Xenon 133 and the HmPAO-{sup 99m}Tc. A 66 year old men had presented a brutal left hemiplegia with transient troubles of consciousness in relation with a right protuberant infarct without hemispheric lesions. The functional studies were performed 4 months after the onset, successively by the Xe inhalation method and immediately after the HmPAO study. On a patient kept still on the camera bed when cerebral blood flow (CBF) study depicted both a right cerebellar low flow and a slightly decreased CBF in the controlateral hemisphere ('hemispheric diaschisis'), the HmPAO SPECT was normal. This observation illustrates both the crossed hemispheric diaschisis and a new type of discrepancy: indeed, the known cases were until now in relation with alterations of the blood: brain barrier, which doses not exist in our report. The explanation of this type of discrepancy remains unclear but is probably linked with the HMPAO retention mechanisms. (author)

  13. Blood pressure and blood flow variation during postural change from sitting to standing: model development and validation

    DEFF Research Database (Denmark)

    Olufsen, M.S.; Ottesen, Johnny T.; Tran, H.T.

    2005-01-01

    Short-term cardiovascular responses to postural change from sitting to standing involve complex interactions between the autonomic nervous system, which regulates blood pressure, and cerebral autoregulation, which maintains cerebral perfusion. We present a mathematical model that can predict...... dynamic changes in beat-to-beat arterial blood pressure and middle cerebral artery blood flow velocity during postural change from sitting to standing. Our cardiovascular model utilizes 11 compartments to describe blood pressure, blood flow, compliance, and resistance in the heart and systemic circulation....... To include dynamics due to the pulsatile nature of blood pressure and blood flow, resistances in the large systemic arteries are modeled using nonlinear functions of pressure. A physiologically based submodel is used to describe effects of gravity on venous blood pooling during postural change. Two types...

  14. Effects of Yunnan Baiyao through inner layer of cerebral dura mater on cerebral perfusion and oxygen metabolism in rabbits with severe traumatic brain injury%硬脑膜夹层导入云南白药对兔重型颅脑创伤后脑灌注和氧代谢的影响

    Institute of Scientific and Technical Information of China (English)

    徐震; 吕晓皑; 尹利明; 竺国充; 张昕; 李徐; 陈祖鹏

    2012-01-01

    Objective: To explore the effects of Yunnan Baiyao through inner layer of cerebral dura mater on cerebral perfusion and oxygen metabolism in rabbits with severe traumatic brain injury. Methods: 40 New Zealand white rabbits were divided into cerebral dura mater Yunnan Baiyao group(A group), intravenous Mannitol group(B group), oral Yunnan Baiyao group (C group) and control group(D group). Record ICP, CPP and MABP. TCD measured cerebral blood flow volume. Monitor blood gas analysis in femora) artery and internal jugular venous bulb, accounting the CEO2 and D-values of glucose and lactic acid between artery and venous bulb. Results: From 12 to 36 hour after therapy: the ICP of A was highter than B, the CPP and CBFV were lower than B (P<0.05). At 48 hour: the ICP of A was highter than B and lower than C and D, the CPP was lower than B and highter than Cand D, while the CBFV of A was highter than C and D(P<0.05). From 60 to 96 hour: the ICP of A was lower than C and D, the CPP of A was highter than C and D, the CBFV of A was highter than B, C and D(P<0.05). From 36 to 96: The Glua-jv and CEO2 of A were highter than B, C and D, while the Lacjv-a was lower than B, C and D(P<0.05). Conclusion: Yunnan Baiyao through cerebral dura mater can reach effective treatment concentration in brain. By increasing the efficiency of oxygen metabolism of brain it can ameliorate brain cell hypoxia and energy metabolism handicap, adjust cerebral microcirculation, thus improves cytotoxic brain edema, decreases cerebral blood flow resistance, reduces ICP and increase the CPP and CBFV.%目的:探讨硬脑膜夹层应用云南白药对兔重型颅脑创伤后颅内压、脑血流量和脑代谢的影响.方法:将40只雄性新西兰大白兔分为硬脑膜夹层云南白药组(A组)、静脉甘露醇组(B组)、口服云南白药组(C组)和空白组(D组),制作重型颅脑创伤模型,行颅内压(ICP)监测,记录平均动脉压(MABP),计算脑灌注压(CPP),经颅多普勒(TCD)测定脑

  15. Bubble dynamics in perfused tissue undergoing decompression.

    Science.gov (United States)

    Meisel, S; Nir, A; Kerem, D

    1981-02-01

    A mathematical model describing bubble dynamics in a perfused tissue undergoing decompression is presented, taking into account physical expansion and inward diffusion from surrounding supersaturated tissue as growth promoting factors and tissue gas elimination by perfusion, tissue elasticity, surface tension and inherent unsaturation as resolving driving forces. The expected behavior after a step reduction of pressure of a bubble initially existing in the tissue, displaying both growth and resolution has been demonstrated. A strong perfusion-dependence of bubble resolution time at low perfusion rates is apparent. The model can account for various exposure pressures and saturation fractions of any inert gas-tissue combination for which a set of physical and physiological parameters is available.

  16. Impacts of acupuncture on blood pressure and hematoma in patients of cerebral hemorrhage at the early stage

    Institute of Scientific and Technical Information of China (English)

    陶文强

    2014-01-01

    Objective To explore the therapeutic effect of acupuncture for hypertensive cerebral hemorrhage at the early stage.Methods Fifty-four cases of small-amount cerebral hemorrhage were randomized into an acupuncture group and a conventional treatment group,27 cases in each.In the conventional treatment group,special care,oxygen therapy,nerve nutrition and symptomatic support were applied.If necessary,dehydrant and hypotensive drugs were prescribed for antihypertension,or surgery

  17. Impaired Cerebral Autoregulation during Head Up Tilt in Patients with Severe Brain Injury.

    Directory of Open Access Journals (Sweden)

    Christian Gunge Riberholt

    Full Text Available Early mobilization is of importance for improving long-term outcome for patients after severe acquired brain injury. A limiting factor for early mobilization by head-up tilt is orthostatic intolerance. The purpose of the present study was to examine cerebral autoregulation in patients with severe acquired brain injury and a low level of consciousness. Fourteen patients with severe acquired brain injury and orthostatic intolerance and fifteen healthy volunteers were enrolled. Blood pressure was evaluated by pulse contour analysis, heart rate and RR-intervals were determined by electrocardiography, middle cerebral artery velocity was evaluated by transcranial Doppler, and near-infrared spectroscopy determined frontal lobe oxygenation in the supine position and during head-up tilt. Cerebral autoregulation was evaluated as the mean flow index calculated as the ratio between middle cerebral artery mean velocity and estimated cerebral perfusion pressure. Patients with acquired brain injury presented an increase in mean flow index during head-up tilt indicating impaired autoregulation (P < 0.001. Spectral analysis of heart rate variability in the frequency domain revealed lower magnitudes of ~0.1 Hz spectral power in patients compared to healthy controls suggesting baroreflex dysfunction. In conclusion, patients with severe acquired brain injury and orthostatic intolerance during head-up tilt have impaired cerebral autoregulation more than one month after brain injury.

  18. Wavelet coherence analysis of dynamic cerebral autoregulation in neonatal hypoxic–ischemic encephalopathy

    Directory of Open Access Journals (Sweden)

    Fenghua Tian

    2016-01-01

    Full Text Available Cerebral autoregulation represents the physiological mechanisms that keep brain perfusion relatively constant in the face of changes in blood pressure and thus plays an essential role in normal brain function. This study assessed cerebral autoregulation in nine newborns with moderate-to-severe hypoxic–ischemic encephalopathy (HIE. These neonates received hypothermic therapy during the first 72 h of life while mean arterial pressure (MAP and cerebral tissue oxygenation saturation (SctO2 were continuously recorded. Wavelet coherence analysis, which is a time-frequency domain approach, was used to characterize the dynamic relationship between spontaneous oscillations in MAP and SctO2. Wavelet-based metrics of phase, coherence and gain were derived for quantitative evaluation of cerebral autoregulation. We found cerebral autoregulation in neonates with HIE was time-scale-dependent in nature. Specifically, the spontaneous changes in MAP and SctO2 had in-phase coherence at time scales of less than 80 min (<0.0002 Hz in frequency, whereas they showed anti-phase coherence at time scales of around 2.5 h (~0.0001 Hz in frequency. Both the in-phase and anti-phase coherence appeared to be related to worse clinical outcomes. These findings suggest the potential clinical use of wavelet coherence analysis to assess dynamic cerebral autoregulation in neonatal HIE during hypothermia.

  19. Cerebral blood flow and autoregulation: current measurement techniques and prospects for noninvasive optical methods.

    Science.gov (United States)

    Fantini, Sergio; Sassaroli, Angelo; Tgavalekos, Kristen T; Kornbluth, Joshua

    2016-07-01

    Cerebral blood flow (CBF) and cerebral autoregulation (CA) are critically important to maintain proper brain perfusion and supply the brain with the necessary oxygen and energy substrates. Adequate brain perfusion is required to support normal brain function, to achieve successful aging, and to navigate acute and chronic medical conditions. We review the general principles of CBF measurements and the current techniques to measure CBF based on direct intravascular measurements, nuclear medicine, X-ray imaging, magnetic resonance imaging, ultrasound techniques, thermal diffusion, and optical methods. We also review techniques for arterial blood pressure measurements as well as theoretical and experimental methods for the assessment of CA, including recent approaches based on optical techniques. The assessment of cerebral perfusion in the clinical practice is also presented. The comprehensive description of principles, methods, and clinical requirements of CBF and CA measurements highlights the potentially important role that noninvasive optical methods can play in the assessment of neurovascular health. In fact, optical techniques have the ability to provide a noninvasive, quantitative, and continuous monitor of CBF and autoregulation.

  20. Cerebral Vasospasm Pharmacological Treatment: An Update

    OpenAIRE

    Ioannis Siasios; Kapsalaki, Eftychia Z; Fountas, Kostas N

    2013-01-01

    Aneurysmal subarachnoid hemorrhage- (aSAH-) associated vasospasm constitutes a clinicopathological entity, in which reversible vasculopathy, impaired autoregulatory function, and hypovolemia take place, and lead to the reduction of cerebral perfusion and finally ischemia. Cerebral vasospasm begins most often on the third day after the ictal event and reaches the maximum on the 5th–7th postictal days. Several therapeutic modalities have been employed for preventing or reversing cerebral vasosp...

  1. Perfusion-weighted MR imaging in persistent hemiplegic migraine

    Energy Technology Data Exchange (ETDEWEB)

    Mourand, Isabelle; Menjot de Champfleur, Nicolas; Carra-Dalliere, Clarisse; Le Bars, Emmanuelle; Bonafe, Alain; Thouvenot, Eric [Hopital Gui de Chauliac, Service de Neuroradiologie, Montpellier (France); Roubertie, Agathe [Hopital Gui de Chauliac, Service de Neuropediatrie, Montpellier (France)

    2012-03-15

    Hemiplegic migraine is a rare type of migraine that has an aura characterized by the presence of motor weakness, which may occasionally last up to several days, and then resolve without sequela. Pathogenesis of migraine remains unclear and, recently, perfusion-weighted imaging (PWI) has provided a non-invasive method to study hemodynamic changes during acute attacks. Two female patients were admitted in our hospital suffering from prolonged hemiparesis. In both cases, they underwent MRI examination using a 1.5 T magnet including axial diffusion-weighted and perfusion sequences. From each perfusion MRI acquisition two regions of interest were delineated on each hemisphere and, the index of flow, cerebral blood volume, mean transit time, and time to peak were recorded and asymmetry indices from each perfusion parameter were calculated. Perfusion alterations were detected during the attacks. In one case, we observed, after 3 h of left hemiparesia, hypoperfusion of the right hemisphere. In the other case, who presented a familial hemiplegic migraine attack, on the third day of a persistent aura consisting of right hemiplegia and aphasia, PWI revealed hyperperfusion of the left hemisphere. Asymmetry indices for temporal parameters (mean transit time and time to peak) were the most sensitive. These findings resolved spontaneously after the attacks without any permanent sequel or signs of cerebral ischemia on follow-up MRI. PWI should be indicated for patients with migraine attacks accompanied by auras to assess the sequential changes in cerebral perfusion and to better understand its pathogenesis. (orig.)

  2. Role of magnetic resonance perfusion studies in moyamoya disease

    Directory of Open Access Journals (Sweden)

    Khanna Paritosh

    2004-04-01

    Full Text Available Moyamoya disease, Japanese for ′puff of smoke′, is a rare disease that presents most commonly with recurrent TIAs (transient ischemic attacks / stroke in childhood. Ischemic symptoms in patients with moyamoya disease are usually due to hemodynamically-mediated perfusion failure. Identification of abnormal tissue perfusion is an important aspect of the evaluation of these patients. We present the radiological features including the Magnetic Resonance (MR Perfusion findings illustrating the hemodynamic changes of cerebral ischemia in a case of moyamoya disease.

  3. Lesion area detection using source image correlation coefficient for CT perfusion imaging.

    Science.gov (United States)

    Fan Zhu; Rodriguez Gonzalez, David; Carpenter, Trevor; Atkinson, Malcolm; Wardlaw, Joanna

    2013-09-01

    Computer tomography (CT) perfusion imaging is widely used to calculate brain hemodynamic quantities such as cerebral blood flow, cerebral blood volume, and mean transit time that aid the diagnosis of acute stroke. Since perfusion source images contain more information than hemodynamic maps, good utilization of the source images can lead to better understanding than the hemodynamic maps alone. Correlation-coefficient tests are used in our approach to measure the similarity between healthy tissue time-concentration curves and unknown curves. This information is then used to differentiate penumbra and dead tissues from healthy tissues. The goal of the segmentation is to fully utilize information in the perfusion source images. Our method directly identifies suspected abnormal areas from perfusion source images and then delivers a suggested segmentation of healthy, penumbra, and dead tissue. This approach is designed to handle CT perfusion images, but it can also be used to detect lesion areas in magnetic resonance perfusion images.

  4. Cerebral perfusion semi-quantitative imaging for assessing the treatment of delayed encephalopathy from carbon monoxide poisoning%脑血流灌注半定量法显像评价高压氧联合药物治疗一氧化碳中毒迟发性脑病疗效

    Institute of Scientific and Technical Information of China (English)

    熊冰; 周游; 蔡亚利; 刘洪彪; 汤中泉; 孙达; 徐昕; 刘文明

    2009-01-01

    目的 对比研究一氧化碳中毒后迟发性脑病(DEACMP)患者在高压氧(HBO)联合药物治疗前、后单光子发射计算机断层成像(SPECT)脑血流灌注显像结果,并对其优越性及临床意义进行评价.方法 34例DEACMP患者接受20~40次HBO联合药物治疗,并在治疗前、后用双半胱乙酯(~(99m)Tc-ECD)脑SPECT血流灌注扫描半定量法进行疗效监测和对比分析.结果 HBO治疗后,DEACMP患者脑血流灌注减低区有明显改善,脑SPECT血流灌注半定量值与治疗前比较,差异有统计学意义(P<0.05),而治疗前、后脑磁共振显像无明显差异.结论 脑SPECT血流灌注半定量法显像在DEACMP的诊断和HBO治疗的疗效监测中可起重要作用.%Objective To evaluate the effects of hyperbaric oxygen (HBO) combined with drug therapy on patients with delayed encephalopathy caused by carbon monoxide poisoning ( COP). Methods Twenty to forty sessions of HBO therapy were used to treat 34 COP patients. Assessment relied on 99mTc-ethyl cysteinate dimer (~(99m)Tc-ECD) single photon emission computed tomography (SPECT) imaging of cerebral perfusion before and after treatment. Results After HBO therapy, cerebral perfusion in the COP patients improved significantly. There was a significant difference of the SPECT images before and after treatment. Conclusions SPECT imaging of cerebral perfusion can play an important role in the diagnosis of delayed encephalopathy caused by carbon monoxide poisoning, and it can be used for the therapeutic surveillance of HBO treatment.

  5. Multi-delay arterial spin labeling perfusion MRI in moyamoya disease-comparison with CT perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Rui [Chinese Academy of Sciences, State Key Laboratory of Brain and Cognitive Science, Beijing MRI Center for Brain Research, Institute of Biophysics, Beijing (China); University of Chinese Academy of Sciences, Graduate School, Beijing (China); UCLA-Beijing Joint Center for Advanced Brain Imaging, Beijing (China); UCLA-Beijing Joint Center for Advanced Brain Imaging, Los Angeles, CA (United States); Yu, Songlin [Capital Medical University, Department of Neurosurgery, Beijing Tiantan Hospital, Beijing (China); University of California Los Angeles, Department of Neurology, Los Angeles (United States); Alger, Jeffry R.; Wang, Danny J.J. [University of California Los Angeles, Department of Neurology, Los Angeles (United States); UCLA-Beijing Joint Center for Advanced Brain Imaging, Beijing (China); UCLA-Beijing Joint Center for Advanced Brain Imaging, Los Angeles, CA (United States); Zuo, Zhentao; Wang, Bo [Chinese Academy of Sciences, State Key Laboratory of Brain and Cognitive Science, Beijing MRI Center for Brain Research, Institute of Biophysics, Beijing (China); Chen, Juan [Beijing Hospital, Department of Radiology, Beijing (China); Wang, Rong; Zhao, Jizong [Capital Medical University, Department of Neurosurgery, Beijing Tiantan Hospital, Beijing (China); An, Jing [Siemens Shenzhen Magnetic Resonance Ltd, Shenzhen (China); Xue, Rong [Chinese Academy of Sciences, State Key Laboratory of Brain and Cognitive Science, Beijing MRI Center for Brain Research, Institute of Biophysics, Beijing (China); UCLA-Beijing Joint Center for Advanced Brain Imaging, Beijing (China); UCLA-Beijing Joint Center for Advanced Brain Imaging, Los Angeles, CA (United States)

    2014-05-15

    To present a multi-delay pseudo-continuous ASL (pCASL) protocol that offers simultaneous measurements of cerebral blood flow (CBF) and arterial transit time (ATT), and to study correlations between multi-delay pCASL and CT perfusion in moyamoya disease. A 4 post-labeling delay (PLD) pCASL protocol was applied on 17 patients with moyamoya disease who also underwent CT perfusion imaging. ATT was estimated using the multi-delay protocol and included in the calculation of CBF. ASL and CT perfusion images were rated for lesion severity/conspicuity. Pearson correlation coefficients were calculated across voxels between the two modalities in grey and white matter of each subject respectively and between normalized mean values of ASL and CT perfusion measures in major vascular territories. Significant associations between ASL and CT perfusion were detected using subjective ratings, voxel-wise analysis in grey and white matter and region of interest (ROI)-based analysis of normalized mean perfusion. The correlation between ASL CBF and CT perfusion was improved using the multi-delay pCASL protocol compared to CBF acquired at a single PLD of 2 s (P < 0.05). There is a correlation between perfusion data from ASL and CT perfusion imaging in patients with moyamoya disease. Multi-delay ASL can improve CBF quantification, which could be a prognostic imaging biomarker in patients with moyamoya disease. (orig.)

  6. Effects of the Oxygen-Carrying Solution OxyVita C on the Cerebral Microcirculation and Systemic Blood Pressures in Healthy Rats

    Directory of Open Access Journals (Sweden)

    Rania Abutarboush

    2014-11-01

    Full Text Available The use of hemoglobin-based oxygen carriers (HBOC as oxygen delivering therapies during hypoxic states has been hindered by vasoconstrictive side effects caused by depletion of nitric oxide (NO. OxyVita C is a promising oxygen-carrying solution that consists of a zero-linked hemoglobin polymer with a high molecular weight (~17 MDa. The large molecular weight is believed to prevent extravasation and limit NO scavenging and vasoconstriction. The aim of this study was to assess vasoactive effects of OxyVita C on systemic blood pressures and cerebral pial arteriole diameters. Anesthetized healthy rats received four intravenous (IV infusions of an increasing dose of OxyVita C (2, 25, 50, 100 mg/kg and hemodynamic parameters and pial arteriolar diameters were measured pre- and post-infusion. Normal saline was used as a volume-matched control. Systemic blood pressures increased (P ≤ 0.05 with increasing doses of OxyVita C, but not with saline. There was no vasoconstriction in small (<50 µm and medium-sized (50–100 µm pial arterioles in the OxyVita C group. In contrast, small and medium-sized pial arterioles vasoconstricted in the control group. Compared to saline, OxyVita C showed no cerebral vasoconstriction after any of the four doses evaluated in this rat model despite increases in blood pressure.

  7. CT perfusion on admission and cognitive functioning 3 months after aneurysmal subarachnoid haemorrhage

    NARCIS (Netherlands)

    Wajer, Irene M. C. Huenges; Cremers, Charlotte H. P.; van Zandvoort, Martine J. E.; Vergouwen, Mervyn D. I.; van der Schaaf, Irene C.; Velthuis, BK; Dankbaar, Jan Willem; Vos, Pieter C.; Visser-Meily, Johanna M. A.; Rinkel, Gabriel J. E.

    2015-01-01

    Many survivors of aneurysmal subarachnoid haemorrhage (aSAH) have persistent cognitive deficits. Underlying causes of these deficits have not been elucidated. We aimed to investigate if cerebral perfusion in the acute phase after aSAH measured with CT perfusion (CTP) is associated with cognitive out

  8. Intra-Arterial MR Perfusion Imaging of Meningiomas: Comparison to Digital Subtraction Angiography and Intravenous MR Perfusion Imaging

    Science.gov (United States)

    Martin, Alastair J.; Alexander, Matthew D.; McCoy, David B.; Cooke, Daniel L.; Lillaney, Prasheel; Moftakhar, Parham; Amans, Matthew R.; Settecase, Fabio; Nicholson, Andrew; Dowd, Christopher F.; Halbach, Van V.; Higashida, Randall T.; McDermott, Michael W.; Saloner, David; Hetts, Steven W.

    2016-01-01

    Background and Purpose To evaluate the ability of IA MR perfusion to characterize meningioma blood supply. Methods Studies were performed in a suite comprised of an x-ray angiography unit and 1.5T MR scanner that permitted intraprocedural patient movement between the imaging modalities. Patients underwent intra-arterial (IA) and intravenous (IV) T2* dynamic susceptibility MR perfusion immediately prior to meningioma embolization. Regional tumor arterial supply was characterized by digital subtraction angiography and classified as external carotid artery (ECA) dural, internal carotid artery (ICA) dural, or pial. MR perfusion data regions of interest (ROIs) were analyzed in regions with different vascular supply to extract peak height, full-width at half-maximum (FWHM), relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), and mean transit time (MTT). Linear mixed modeling was used to identify perfusion curve parameter differences for each ROI for IA and IV MR imaging techniques. IA vs. IV perfusion parameters were also directly compared for each ROI using linear mixed modeling. Results 18 ROIs were analyzed in 12 patients. Arterial supply was identified as ECA dural (n = 11), ICA dural (n = 4), or pial (n = 3). FWHM, rCBV, and rCBF showed statistically significant differences between ROIs for IA MR perfusion. Peak Height and FWHM showed statistically significant differences between ROIs for IV MR perfusion. RCBV and MTT were significantly lower for IA perfusion in the Dural ECA compared to IV perfusion. Relative CBF in IA MR was found to be significantly higher in the Dural ICA region and MTT significantly lower compared to IV perfusion. PMID:27802268

  9. Compromised cerebrovascular modulation in chronic anxiety: evidence from cerebral blood flow velocity measured by transcranial Doppler sonography

    Institute of Scientific and Technical Information of China (English)

    Hong-Liang Zhang; Zhen-Ni Guo; Ge Yang; Le Yang; Ke Han; Jiang Wu; Yingqi Xing; Yi Yang

    2012-01-01

    Objective Cerebral autoregulation (CA) is the mechanism by which constant cerebral blood flow is maintained despite changes in cerebral perfusion pressure.CA can be evaluated by dynamic monitoring of cerebral blood flow velocity (CBFV) with transcranial Doppler sonography (TCD).The present study aimed to explore CA in chronic anxiety.Methods Subjects with Hamilton anxiety scale scores ≥14 were enrolled and the dynamic changes of CBFV in response to an orthostatic challenge were investigated using TCD.Results In both the anxious and the healthy subjects,the mean CBFV was significantly lower in the upright position than when supine.However,the CBFV changes from supine to upright differed between the anxious and the healthy groups.Anxious subjects showed more pronounced decreases in CBFV with abrupt standing.Conclusion Our results indicate that cerebrovascular modulation is compromised in chronic anxiety; anxious subjects have some insufficiency in maintaining cerebral perfusion after postural change.Given the fact that anxiety and impaired CA are associated with cardiovascular disease,early ascertainment of compromised cerebrovascular modulation using TCD might suggest interventional therapies in the anxious population,and improve the primary prevention of cardiovascular disease.

  10. Modification of the cerebral perfusion during a chemotherapy by arabinoside cytosine (A.R.A.C.) among patients suffering of an acute myelo-blastic leukemia (A.M.L.); Modification de la perfusion cerebrale au cours d'une chimiotherapie par cytosine arabinoside (ARAC) chez les patients atteints d'une leucemie aigue myeloblastique (LAM)

    Energy Technology Data Exchange (ETDEWEB)

    Modzelewski, R.; Vera, P. [Universite de Medecine de Rouen, QUANT.I.F-LITIS EA4108, departement de medecine nucleaire, 76 (France); Lepretre, S.; Tilly, H. [Centre Henri-Becquerel, departement d' hematologie, 76 - Rouen (France); Martinaud, O.; Hannequin, D. [CHU de Rouen, departement