No abstract available.
Diagnosis* ; Pulmonary Embolism*

No abstract available.
Diagnosis ; Ductus Arteriosus, Patent ; Endarteritis ; Pulmonary Embolism

Humans ; Pulmonary Embolism ; diagnosis ; therapy ; Venous Thromboembolism ; diagnosis ; therapy

Adult ; Embolism, Paradoxical ; diagnosis ; therapy ; Humans ; Male ; Pulmonary Embolism ; diagnosis ; therapy

Endosonography ; methods ; Humans ; Male ; Middle Aged ; Pulmonary Embolism ; diagnosis

Child ; Humans ; Pulmonary Embolism ; diagnosis ; etiology ; therapy ; Risk Factors

PURPOSE: To evaluate the incidence and type of low attenuation seen on high resolution computed tomography (HRCT) performed after artificially induced pulmonary embolism. MATERIALS AND METHODS: Using permanent embolic materials, pulmonary embolism was induced in ten Yorkshire pigs. Pre- and postembolic pulmonary angiography was performed, and HRCT was performed immediately and 1, 3, and 6 weeks after embolization. The incidence and type of low attenuation of all segments, as seen on HRCT, was evaluated. Low attenuation was classified as mottled, lobular, segmental, or peripheral. The pigs were sacrified after 6 weeks and contact radiographs were obtained. RESULTS: Low attenuation developed in eight of ten pigs. Pulmonary angiography revealed arterial occlusion in 15 large and 19 small segmental arteries (34 of 45 segments). In the remaining 11 segments, follow-up HRCT demonstrated areas of low attenuation. This was present in 25 of 35 segments (71%) as seen on HRCT images obtained immediately; in 16 of 41 segments (39 %) on images obtained 1 week after embolization; in 17 of 41 segments (41 %) on those acquired at 3 weeks; and in 25 of 45 segments (56 %) on those acquired at 6 weeks. The overall incidence of low attenuation was 83/166 (50 %). The types of low attenuation were mottled in 32/83 cases, lobular in 13/83, segmental in 13/83, and peripheral in 25/83. In large segmental arterial occlusion, the incidence of low attenuation on HRCT was 100% immediately, 57% at 1 week, 60% at 3 weeks, and 80 % at 6 weeks. In small segmental arterial occlusion, the incidence was 47%, 25 %, 11 %, and 21 % respectively. The overall incidence of low attenuation was 40/55 (73 %) in large segmental arterial occlusion and 18/71 ( 25%) in small segmental arterial occlusion. CONCLUSION: Low attenuation on HRCT is a finding of pulmonary embolism and is more common on HRCT performed immediately after embolization (71%) and in large segmental arterial occlusion (73%). Low attenuation on HRCT is an ancillary finding and may be useful in the diagnosis of pulmonary embolism.
Angiography ; Arteries ; Diagnosis ; Follow-Up Studies ; Incidence ; Pulmonary Embolism* ; Swine*

BACKGROUNDDuring the process of bone cement joint replacement, some patients show a series of complications, such as a sudden drop in blood pressure or dyspnea. The cause of the complication is considered to be due to emboli caused by the femur prosthesis insertion. The purpose of the present study was to detect the pulmonary embolism in rabbits after bone cement perfusion by radioimmunoimaging, and to explore its protective measures.

METHODSForty rabbits, 2.5 - 3.0 kg weight, were randomly assigned to four groups, with ten rabbits in each group. Group I (no intervention): Bone cement perfusion was done after medullary cavity reaming and pressurizing. Group II (epinephrine hydrochloride intervention): The medullary cavity was rinsed with a 1:10 000 normal saline-diluted epinephrine hydrochloride solution followed by bone cement perfusion after medullary cavity reaming and pressurizing. Group III (fibrin sealant intervention): The medullary cavity was precoated with fibrin sealant followed by bone cement perfusion after medullary cavity reaming and pressurizing. Group IV (blank control group): The medullary cavity was not perfused with bone cement after reaming. In each group, the rabbits underwent femoral head resection and medullary cavity reaming. Before bone cement perfusion, 2 ml of developing tracer was injected through the ear vein. Radionuclide imaging was performed at 60, 120, and 180 minutes after bone cement perfusion, and the pulmonary radioactivity in vivo was measured. The rabbits were immediately sacrificed, and the pulmonary tissue was removed and its radioactivity was measured in vitro. Pulmonary tissue was then fixed and the pulmonary embolism and the associated pathological changes were observed.

RESULTSThe pulmonary radioactivity in vivo was measured at 60, 120, and 180 minutes after bone cement perfusion. The radioactivities of the four groups were 11.67 ± 2.16, 14.59 ± 2.92 and 18.43 ± 4.83 in group I; 8.37 ± 3.05, 10.35 ± 2.24 and 11.48 ± 2.96 in group II; 3.91 ± 1.19, 5.53 ± 2.95 and 7.25 ± 1.26 in group III; 1.04 ± 0.35, 1.14 ± 0.87 and 1.43 ± 0.97 in group IV. The radioactivities of groups I, II, III at 60, 120 and 180 minutes were significantly higher than group IV (P < 0.05). The pulmonary embolism could be detected. Pretreatment with epinephrine hydrochloride and fibrin sealant significantly decreased the pulmonary radioactivity in group II and group III, but it was still higher than in the group IV.

CONCLUSIONSRadioimmunoimaging is an alternative method for the dynamic observation of rabbit pulmonary embolism after bone cement perfusion. Radioimmunoimaging is the optional way to evaluate the effect of pretreatment with epinephrine hydrochloride or fibrin sealant on pulmonary embolism after bone cement perfusion.

PURPOSE: The purpose of our study was to compare the diagnostic value of contrast-enhanced spiral CT scanning and pulmonary angiography in detecting central and peripheral pulmonary embolism (PE) in pigs. MATERIALS AND METHODS: Experiments were performed in a porcine model of acute pulmonary embolism. Five pigs underwent contrast-enhanced spiral CT and pulmonary angiography after central venous administration of embolic material (Konyak). Three thoracic radiologists read the films and the results were compared with the findings of pathologic specimens. RESULTS: Of 85 cases of PE detected pathologically, 78 (91.8 %) were visible with spiral CT and 65 (76.5 %) with pulmonary angiography. Sensitivity and specificity for the detection of central emboli were 95 % and 100 %, respectively, with spiral CT, and 89 % and 100 %, respectively, with pulmonary angiography. Sensitivity and specificity for the detection of peripheral emboli were 88 % and 99 %, respectively, with spiral CT, and 64% and 100 %, respectively, with pulmonary angiography. CONCLUSION: Contrast-enhanced spiral CT is a very useful method for the diagnosis of both peripheral and central pulmonary embolism. Compared to pulmonary angiography its sensitivity and specificity are high.
Angiography ; Diagnosis ; Pulmonary Embolism* ; Sensitivity and Specificity ; Swine ; Tomography, Spiral Computed*

PURPOSE: The purpose of our study was to compare the diagnostic value of contrast-enhanced spiral CT scanning and pulmonary angiography in detecting central and peripheral pulmonary embolism (PE) in pigs. MATERIALS AND METHODS: Experiments were performed in a porcine model of acute pulmonary embolism. Five pigs underwent contrast-enhanced spiral CT and pulmonary angiography after central venous administration of embolic material (Konyak). Three thoracic radiologists read the films and the results were compared with the findings of pathologic specimens. RESULTS: Of 85 cases of PE detected pathologically, 78 (91.8 %) were visible with spiral CT and 65 (76.5 %) with pulmonary angiography. Sensitivity and specificity for the detection of central emboli were 95 % and 100 %, respectively, with spiral CT, and 89 % and 100 %, respectively, with pulmonary angiography. Sensitivity and specificity for the detection of peripheral emboli were 88 % and 99 %, respectively, with spiral CT, and 64% and 100 %, respectively, with pulmonary angiography. CONCLUSION: Contrast-enhanced spiral CT is a very useful method for the diagnosis of both peripheral and central pulmonary embolism. Compared to pulmonary angiography its sensitivity and specificity are high.
Angiography ; Diagnosis ; Pulmonary Embolism* ; Sensitivity and Specificity ; Swine ; Tomography, Spiral Computed*