Perfusion scanning

About: Perfusion scanning is a research topic. Over the lifetime, 9496 publications have been published within this topic receiving 223860 citations. The topic is also known as: perfusion imaging.

Cerebral perfusion in early and late opiate withdrawal: a technetium-99m-HMPAO SPECT study

Abstract: The purpose of this study was to determine if cerebral blood flow (CBF) alterations are associated with discontinuation of heroin in chronic heroin users, and whether these alterations are reversible during abstinence. Ten physically healthy opioid-dependent males, hospitalized on an inpatient drug rehabilitation unit, were studied. Each patient had an initial single photon emission computed tomographic (SPECT) scan with the radiotracer technetium-99m-d,l-hexamethylpropyleneamine oxime (99mTc-HMPAO) 1 week after opiate discontinuation and a repeat scan 2 weeks later. The initial scans in 9 of the 10 subjects demonstrated significant, often discrete, perfusion defects, especially in the frontal, parietal, and temporal cortices. Two weeks later, repeat brain perfusion SPECT scans showed improvement in all nine subjects who had abnormal scans. Comparisons of the first scan with the second scan showed an increase in cortical uptake on the repeat SPECT study. All subjects had normal computed tomographic or magnetic resonance imaging scans. The results of this preliminary study suggest that the chronic use of opiates, like chronic use of cocaine, results in perfusion abnormalities without corresponding abnormalities on imaging studies of cerebral anatomy and morphology. This study also documents that these perfusion defects are partially reversible with short-term abstinence.

Perfusion imaging using dynamic arterial spin labeling (DASL).

Abstract: Recently, a technique based on arterial spin labeling, called dynamic arterial spin labeling (DASL (Magn Reson Med 1999;41:299‐ 308)), has been introduced to measure simultaneously the transit time of the labeled blood from the labeling plane to the exchange site, the longitudinal relaxation time of the tissue, and the perfusion of the tissue. This technique relies on the measurement of the tissue magnetization response to a time varying labeling function. The analysis of the characteristics of the tissue magnetization response (transit time, filling time constant, and perfusion) allows for quantification of the tissue perfusion and for transit time map computations. In the present work, the DASL scheme is used in conjuction with echo planar imaging at 4.7 T to produce brain maps of perfusion and transit time in the anesthetized rat, under graded hypercapnia. The data obtained show the variation of perfusion and transit time as a function of arterial pCO2. Based on the data, CO2 reactivity maps are computed. Magn Reson Med 45:1021‐1029, 2001. Published 2001 Wiley-Liss, Inc. †

Screening of Multidrug-Resistance Sensitive Drugs by In Situ Brain Perfusion in P-Glycoprotein-Deficient Mice

Abstract: Purpose. This study was conducted to assess the influence of P-glycoprotein (P-gp) on brain uptake of multidrug resistance sensitive drugs using an in situbrain perfusion technique in P-gp-deficient (mdr1a[−/−]) and wild-type mice.

Imaging of myocardial perfusion with magnetic resonance.

Abstract: Coronary artery disease (CAD) is currently the leading cause of death in developed nations. Reflecting the complexity of cardiac function and morphology, noninvasive diagnosis of CAD represents a major challenge for medical imaging. Although coronary artery stenoses can be depicted with magnetic resonance (MR) and computed tomography (CT) techniques, its functional or hemodynamic impact frequently remains elusive. Therefore, there is growing interest in other, target organ-specific parameters such as myocardial function at stress and first-pass myocardial perfusion imaging to assess myocardial blood flow. This review explores the pathophysiologic background, recent technical developments, and current clinical status of first-pass MR imaging (MRI) of myocardial perfusion.