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.

Tumor angiogenesis and dynamic CT in colorectal carcinoma: Radiologic-pathologic correlation

Abstract: AIM: To investigate the correlation between microvessel density and spiral CT perfusion imaging in colorectal carcinoma. METHODS: Thirty-seven patients, with histologically proven colorectal carcinoma, underwent water enema spiral CT scan. The largest axial surface of the primary tumor was searched on unenhanced spiral CT images. At this level, the enhanced dynamic scan series was acquired. Time-density curves (TDC) were created from the region of interest drawn over the tumor, target artery by Toshiba Xpress/SX spiral CT with perfusion functional software. Then the perfusion was calculated. Microvessel density (MVD) was evaluated using immunohistochemical staining of surgical specimens with anti-CD34, and then MVD was correlated with perfusion. RESULTS: MVD of colorectal carcinomas was 33.11-173.44, mean 87.28, and perfusion was 15.60-64.80 mL/min/ 100 g, mean 39.74 mL/min/100 g. MVD and perfusion were not associated with invasive depth, metastasis and disease stage, and they all decreased with increasing Dukes’ stage, but no significant correlation was found between them (r = 0.18, P = 0.29). CONCLUSION: There is no significant correlation between MVD and perfusion. Neovascularizaton and perfusion are highly presented in early colorectal carcinoma. CT perfusion imaging may be more suited for assessing tumorigenesis in colorectal carcinoma than histological MVD technique.

Diagnostic testing strategies for coronary artery disease: special issues related to gender.

Abstract: Early reports of the prevalence, diagnosis, and outcomes of coronary artery disease (CAD) in women have led to the acceptance of several myths concerning noninvasive diagnostic studies in women. Many of the myths can be explained by age-related differences in prevalence, methodological errors that exclude women from enrollment, worse clinical baseline risk profiles, comorbid diseases at the time of interventions, and smaller coronary vessels. Awareness of these age-related prevalence factors in women and the potential for delaying the onset of CAD by estrogen treatment in postmenopausal women must be considered in assessing the accuracy of diagnostic studies. The critical role of noninvasive testing in women is to diagnose CAD accurately in a population with a lower prevalence of disease prior to the development of more severe clinical manifestations when therapeutic interventions have a higher risk and a poor outcome. Exercise radionuclide ventriculography has lower specificity in women, which may be due to gender differences in the response to excercise. Radionuclide perfusion imaging for the detection of CAD is accurate, there is extensive published literature, and it is used widely. High-dose dipyridamole in combination with echocardiography is not widespread in the United States; most pharmacologic echocardiographic studies are performed using dobutamine, and there are no reports on gender differences using dobutamine echocardiography. At this time, however, there is a paucity of published data on accuracy and no information on the prognostic value of this method. Both perfusion imaging and echocardiography have a better diagnostic accuracy than electrocardiographic stress testing. Myocardial perfusion imaging with thallium-201 or Tc-99m sestamibi identifies not just the presence or absence of CAD, it also prognostically identifies those patients with more severe disease who may benefit from invasive diagnostic testing and possible therapeutic interventions. Technetium-99m perfusion agents offer several advantages over thallium-201 : less attenuation, the ability to measure first-pass ejection fraction, and gated image acquisition. All 3 of these characteristics are expected to improve both sensitivity and specificity in women.

Resting brain perfusion in social anxiety disorder : A voxel-wise whole brain comparison with healthy control subjects

Abstract: Introduction Social anxiety disorder (SAD) is a condition characterised by fears of social interaction and performance situations. SAD may be related to a dysregulation or hyperactivity of cortico-limbic circuitry. This is the first voxel-based whole brain study comparing resting function in SAD to a normal control group. Methods Resting perfusion in adult subjects with generalised SAD was compared with healthy adult volunteers using Statistical Parametric Mapping (SPM). In subjects with SAD, correlations were also sought between resting perfusion and clinical severity measured using the total Liebowitz Social Anxiety Scale (LSAS). Results Twenty-eight subjects with SAD were compared with 19 healthy volunteers. SAD subjects had increased resting perfusion in the frontal cortex and right cerebellum, and decreased perfusion in the pons, left cerebellum, and right precuneus. Total LSAS correlated positively with left frontal cortex resting perfusion, and negatively with right fusiform and right lingual perfusion. Conclusion This study demonstrated increased resting frontal function in social anxiety disorder that is consistent with its hypothesised role in the modulation of excessive limbic activity in anxiety disorders. The correlation of posterior cortical resting function with the severity of SAD symptoms may point to defective perception of self and others.

Role of myocardial perfusion imaging in patients with end-stage renal disease undergoing coronary angiography.

Abstract: Patients with end-stage renal disease (ESRD) are at high risk of cardiovascular events. This study examined the prognostic power of stress myocardial perfusion imaging (MPI) in 150 patients with ESRD (mean age 53 ± 9 years; 30% women; 66% with diabetes mellitus) being evaluated for renal transplantation with known coronary anatomy using angiography. Baseline data in addition to perfusion and angiographic parameters were compared between survivors and nonsurvivors. All-cause mortality was defined as the outcome measure. An abnormal MPI result was present in 85% of patients, 30% had left ventricular (LV) ejection fraction (EF) ≤40%, and 40% had multivessel coronary artery disease using angiography. At a mean follow-up of 3.4 ± 1.5 years, 53 patients died (35%). LVEF ≤40%, LV dilatation (LV end-diastolic volume >90 ml), and diabetes mellitus were associated with higher mortality (all p