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Perfusion Deficit (perfusion + deficit)
Selected AbstractsHarmonic Imaging in Acute Stroke: Detection of a Cerebral Perfusion Deficit With Ultrasound and Perfusion MRIJOURNAL OF NEUROIMAGING, Issue 2 2003Karsten Meyer MD ABSTRACT Perfusion harmonic imaging of the brain is a new ultrasound technique for assessing cerebral perfusion. In a patient with acute middle cerebral artery infarction, this method detected a cerebral perfusion deficit corresponding to the area of delayed perfusion as displayed by perfusion magnetic resonance imaging. [source] The Impact of Chronic Cigarette Smoking on Recovery From Cortical Gray Matter Perfusion Deficits in Alcohol Dependence: Longitudinal Arterial Spin Labeling MRIALCOHOLISM, Issue 8 2009Anderson Mon Background:, Neuroimaging studies reported cerebral perfusion abnormalities in individuals with alcohol use disorders. However, no longitudinal magnetic resonance imaging (MRI) studies of cerebral perfusion changes during abstinence from alcohol have been reported. Methods:, Arterial spin labeling MRI was used to evaluate cortical gray matter perfusion changes in short-term abstinent alcohol dependent individuals in treatment and to assess the impact of chronic cigarette smoking on perfusion changes during abstinence. Seventy-six patients were scanned at least once. Data from 19 non-smoking (17 males, 2 females) and 22 smoking (21 males, 1 female) patients scanned at 1 and 5 weeks of abstinence were used to assess perfusion changes over time. Twenty-eight age-equated healthy controls (25 males, 3 females) were scanned for cross-sectional comparison, 13 of them were scanned twice. Given the age range of the cohort (28 to 68 years), age was used as a covariate in the analyses. Mean perfusion was measured in voxels of at least 80% gray matter in the frontal and parietal lobes and related to neurocognitive and substance use measures. Results:, At 1 week of abstinence, frontal and parietal gray matter perfusion in smoking alcoholics was not significantly different from that in non-smoking alcoholics, but each group's perfusion values were significantly lower than in controls. After 5 weeks of abstinence, perfusion of frontal and parietal gray matter in non-smoking alcoholics was significantly higher than that at baseline. However, in smoking alcoholics, perfusion was not significantly different between the time-points in either region. The total number of cigarettes smoked per day was negatively correlated with frontal gray matter perfusion measured at 5 weeks of abstinence. Lobar perfusion measures did not correlate significantly with drinking severity or cognitive domain measures at either time-point. Conclusion:, Although cerebral perfusion in alcohol dependent individuals shows improvement with abstinence from alcohol, cigarette smoking appears to hinder perfusion improvement. [source] MRI Assessment Followed by Successful Mechanical Recanalization of a Complete Tandem (Internal Carotid/Middle Cerebral Artery) Occlusion and Reversal of a 10-Hour Fixed DeficitJOURNAL OF NEUROIMAGING, Issue 1 2008Catalina C. Ionita MD ABSTRACT BACKGROUND Mechanical clot extraction up to 8 hours after stroke onset is an alternative strategy for opening large vessels, especially for patients ineligible for intravenous thrombolysis. Safety beyond this therapeutic window is untested. METHODS An 81-year-old woman presented 8 hours after she developed left-sided weakness and dysarthria with a National Institutes of Health Stroke Scale (NIHSS) score fluctuating between 6 and 13. Neuroimaging revealed a large perfusion deficit with no diffusion abnormalities. An emergent cerebral angiogram revealed a complete internal carotid artery terminus occlusion. RESULTS Successful mechanical thrombectomy was performed without complication and resulted in almost complete reversal of the patient's deficit to an NIHSS score of 1, 10 hours after stroke onset. CONCLUSION Patients with large hypoperfused areas and minimal diffusion abnormalities on the MRI may benefit from mechanical thrombectomy beyond an 8-hour window. [source] Remote Liver Injury is Attenuated by Adenovirus-Mediated Gene Transfer of Heme Oxygenase-1 During the Systemic Inflammatory Response SyndromeMICROCIRCULATION, Issue 7 2004SARAH D. MCCARTER ABSTRACT Objectives: Adenovirus-mediated gene therapy is being investigated with increasing success for future treatment of autoimmune diseases. However, the use of adenoviruses is still limited by inflammatory and immune responses in the target organ. Previous work by the authors' laboratory established that the adenovirus encoding inducible heme oxygenase (Ad-HO-1) does not elicit the acute hepatic inflammation normally caused by adenoviruses, inviting further investigation in models of severe inflammation. Concurrently, there is increasing evidence for an endogenous protective role for heme oxygenase (HO) in the liver during the systemic inflammatory response syndrome (SIRS). Building on our previous results, this study investigated the effect of Ad-HO-1 pretreatment on remote liver injury during normotensive SIRS, induced by bilateral hind limb ischemia and reperfusion. Methods: Microvascular perfusion and hepatocyte death were quantified using established intravital videomicroscopy techniques. Hepatocellular injury and liver function were assessed using blood-borne indicators. Results: Microvascular perfusion deficits and increased hepatocyte death occurred following limb ischemia and 3 h of reperfusion in vehicle-pretreated animals; however, Ad-HO-1 pretreatment prevented these deficits. In contrast, the increase in serum alanine transaminase levels was unaffected by Ad-HO-1 pretreatment. Serum bilirubin levels were increased during systemic inflammation, predominantly in the conjugated form; and, this increase was prevented by administration of Ad-HO-1. Conclusions: These data indicate that gene transfer of inducible HO is an effective method to protect the liver during SIRS, providing incentive for further investigation into gene therapy strategies exploiting this anti-inflammatory enzyme. [source] | ||||||||||