We performed experiments on anesthetized, open-chest dogs to determine whether the pulmonary chemoreflex (bradycardia and systemic hypotension) evoked by stimulating pulmonary C-fibers also involves reflex changes in coronary vascular resistance. We perfused the circumflex coronary artery at constant pressure (usually 100 mm Hg) and recorded mean circumflex blood flow. Stimulation of pulmonary ...

BACKGROUND AND PURPOSE We sought to investigate whether the combination of conventional, diffusion-weighted, and perfusion-weighted MR imaging increases the diagnostic accuracy of balloon test occlusion of the internal carotid artery. We describe perfusion anomalies and patterns of enhancement seen in areas of altered brain perfusion during MR-monitored temporary balloon occlusion of the intern...

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 immedia...

OBJECTIVE Assess if the main pulmonary artery controlled perfusion over cardiopulmonary bypass (CPB) modifies BNP levels expressed by the ventricular myocardium. METHODS Experimental research involving 32 pigs, divided into two groups according to CPB strategy--group I (cardioplegia) and group II (beating heart). Both groups were allocated into three subgroups according to lung perfusion stra...

Despite the heterogeneous distribution of regional pulmonary perfusion over space, local perfusion remains stable over short time periods (20-100 min). The purpose of this study was to determine whether the spatial distribution of pulmonary perfusion remains stable over longer time periods (1-5 days). Regional blood flow was measured each day for 5 days in five awake standing dogs. Fluorescent ...

Objective: The purpose of this study was to evaluate the correlation between CT perfusion parameters and the hypoxia-inducible factor-1 alpha (HIF-1α), vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and microvessel density (MVD) marked by CD34 molecular of rabbit VX2 liver tumors and to investigate the value of CT perfusion imaging in evaluating tumor angiogenesis...

BACKGROUND Perfusion computed tomography (CT) is a relatively new technique that allows fast evaluation of cerebral hemodynamics by providing perfusion maps and gives confirmation of perfusion deficits in ischemic areas. Some controversies exist regarding accuracy of quantitative detection of tissue viability: penumbra (tissue at risk) or core (necrosis). PURPOSE To define brain tissue viabil...

Abstract Introduction: Isolated perfused heart models such as perfusion and superfusion are commonly used for mammalian heart research. However, there are several fundamental limitations in the current techniques. In perfusion model, a suitable cannula is connected to the aorta and the perfusion is retrogradely performed. But, electrode displacement is a potential unwanted event resulted fr...

Background: Perfusion computed tomography (CT) is an evolving technique in the diagnosis of acute stroke. After complex deconvolution algorithms, perfusion color maps-cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT)— are produced, they give visual confirmation of perfusion deficit in ischemic area, but some discrepancies exist regarding this technique in relia...