technetium-tc-99m-sulfur-colloid and Thrombosis

We employed a canine model of pulmonary embolism induced by injection of radioactive blood clots to investigate effects of changes in cardiac output (CO) on recombinant tissue plasminogen activator- (rtPA) induced pulmonary thrombolysis. Rate and extent of thrombolysis were assessed with a gamma camera. Eighteen dogs were studied. Emboli increased mean pulmonary arterial pressure and decreased CO from 2.6 to 1.9 l/min (P less than 0.001). Subsequently, dogs were randomly divided into three groups: group 1 received 0.5 mg/kg of rtPA over 30 min; 30 min before the same dose regimen of rtPA, in the six group 2 dogs, mean CO was increased to approximately 3.25 l/min by opening one systemic arteriovenous fistula; in the six group 3 dogs, before rtPA, mean CO was increased to approximately 4.5 l/min by opening two or three fistulas. After embolization, CO remained low in group 1; the mean 2-h time-averaged CO was 1.8 l/min. CO was much higher in groups 2 and 3 (3.3 and 4.6 l/min, respectively; both P less than 0.001 compared with group 1; and P less than 0.001, group 2 vs. group 3). Compared with group 1, corresponding to the increased flow in groups 2 and 3, rate and extent of pulmonary thrombolysis significantly increased. These results indicate that an increase in flow per se augments rtPA-induced pulmonary thrombolysis. Also, because thrombolysis was similar between groups 2 and 3, these results define an upper limit to the flow-thrombolytic relationship with rtPA.

Topics: Animals; Cardiac Output; Dogs; Fibrinolytic Agents; Hematocrit; Hemodynamics; Pulmonary Embolism; Starch; Technetium Tc 99m Sulfur Colloid; Thrombosis; Tissue Plasminogen Activator

Radionuclide venography (RNV) and CT with contrast infusion were performed in a patient with superior vena cava (SVC) syndrome and upper extremity swelling due to SVC and bilateral subclavian vein thrombosis resulting from infection of a Le Veen peritoneovenous shunt. Although CT was suggestive of thrombosis and excluded extrinsic compression by a mass, obstruction of the SVC and deliniation of collateral venous channels were best demonstrated by RNV.

Topics: Graft Occlusion, Vascular; Humans; Male; Middle Aged; Peritoneovenous Shunt; Radionuclide Angiography; Subclavian Vein; Superior Vena Cava Syndrome; Technetium Tc 99m Aggregated Albumin; Technetium Tc 99m Sulfur Colloid; Thrombosis; Tomography, X-Ray Computed

The authors report a case of "hot spot" localization on SPECT hepatic scintigraphy secondary to IVC obstruction. The tomographic slices demonstrated the location of the focal increase in radiotracer activity as anterior, within the medial segment of the left lobe of the liver. Radionuclide angiography confirmed the extensive collateral vasculature of IVC obstruction.

Topics: Humans; Liver; Male; Middle Aged; Technetium Tc 99m Sulfur Colloid; Thrombosis; Tomography, Emission-Computed; Vena Cava, Inferior

Three cases in which venous obstruction in the thorax was demonstrated by visualization of collateral circulation during bolus-injection excretory urography are presented. Visualization of these collateral vessels is highly suggestive of venous obstruction even if this condition is clinically unsuspected. The diagnosis may be confirmed by radionuclide venography, which is easily performed and noninvasive, and allows determination of the level of obstruction, as well as the degree of collateral flow.

Topics: Adult; Aged; Collateral Circulation; Female; Humans; Male; Radionuclide Imaging; Sulfur; Technetium; Technetium Tc 99m Sulfur Colloid; Thrombosis; Urography; Vascular Diseases; Vena Cava, Superior

A case of portal vein obstruction with cavernous transformation is presented, in which findings on both Tc-99m-sulfur colloid and HIDA liver scintigrams suggested the diagnosis. These findings included a focal hyperconcentration of colloid on the former and notching of the common bile duct as well as "draping" of the right hepatic duct on the latter. All of these findings were shown at angiography and surgery to be secondary to extensive venous collateral vessels related to portal vein obstruction.

Topics: Abscess; Adult; Bile Ducts, Intrahepatic; Collateral Circulation; Common Bile Duct; Humans; Imino Acids; Liver; Male; Portal Vein; Radionuclide Imaging; Sulfur; Technetium; Technetium Tc 99m Lidofenin; Technetium Tc 99m Sulfur Colloid; Thrombosis