this study was conducted to determine the prevalence of pe in patients with v/q scans interpreted as representing a very low probability (vlp) of pe (1-3 small segmental perfusion defects with a normal chest radiograph). an analysis of the entire data set obtained during the pioped study was performed. of the total of 1,359 patients in whom the presence or absence of pe was confirmed, 80 (6%) p...

UNLABELLED Planning hepatic (90)Y radioembolization activity requires balancing toxicity with efficacy. We developed a dual-tracer SPECT fusion imaging protocol that merges data on radioactivity distribution with physiologic liver mapping. METHODS Twenty-five patients with colorectal carcinoma and bilobar liver metastases received whole-liver radioembolization with resin microspheres prescrib...

Objectives. The measurement of mucociliary transport velocity by rhinoscintigraphy with Tc-99m-macroaggregated albumin ((99m)Tc-MAA) is reliable measure of mucociliary clearance. The aim of this study is to assess the intratest, interobserver, and intraobserver reproducibility of nasal mucociliary transport rate (NMTR) measurement. Materials and Methods. Twenty-two subjects were evaluated to de...

UNLABELLED Selective internal radiation therapy (SIRT), a catheter-based liver-directed modality for treating primary and metastatic liver cancer, requires appropriate planning to maximize its therapeutic response and minimize its side effects. (99m)Tc-macroaggregated albumin (MAA) scanning should precede the therapy to detect any extrahepatic shunting to the lung or gastrointestinal tract. Our...

We have demonstrated that 50-mum-diameter arteriovenous pathways exist in isolated, healthy human and baboon lungs, ventilated and perfused under physiological pressures. These findings have been confirmed and extended by demonstrating the passage of 25-microm microspheres through the lungs of exercising dogs, but not at rest. Determination of blood flow through these large-diameter intrapulmon...

OBJECTIVE Frequent association between liver cirrhosis and hypoxemia has been well documented. It is mostly attributable to intrapulmonary shunt due to dilation of pulmonary vasculature. We performed quantitative lung perfusion scintigraphy to detect an intrapulmonary shunt in cirrhosis patients. METHODS Prior to injection, Tc-99m MAA was applied to thin layer chromatography for quality contr...

The aim of this study was to evaluate the incidence of deep vein thrombosis (DVT) in patients with suspected pulmonary embolism (PE) and the relation between PE and the site of DVT by using technetium-99m-macroaggregated human serum albumin ((99m)Tc-MAA) radionuclide venography (RNV). Technetium-99m-MAA RNV was performed simultaneously with lung perfusion scintigraphy in 123 patients with s...

A 56-yr-old man, two months after an operation for an acoustic neurinoma, gradually developed dyspnea. Massive pulmonary embolism (MPE), with a significant right-to-left (R-L) shunt, was seen in a perfusion scan of the lungs with Tc-99m MAA. Radioactivity was noted in the thyroid, spleen, kidneys and brain. A cardiac ultrasound study did not reveal intracardiac shunting. A few days later, when ...

Pulmonary arteriovenous malformations (PAVMs) are often associated with hereditary haemorrhagic telangiectasia (HHT). The quantification of right-to-left shunts in patients with PAVMs is important in diagnosis and follow up. Traditionally, this shunt is measured by the 100% oxygen method, in which the value for the arteriovenous difference in oxygen content, Cao(2)-CVO(2) (where Cao(2) is the o...

Lung scanning has been recognized as a clinically useful technique for portraying macroscopic pulmonary perfusion defects since it was first reported by Wagner in 1964 (1 ). A number of radiopharmaceuticals have been proposed to assess pulmonary perfusion. Although 1 3 1 I imposes many limitations as a radiotagging agent, the use of iodinated macroaggregated albumin (I-MAA) has received wide ac...