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1.
The clinically suspected deep vein thrombosis (DVT) should always be confirmed by instrumental procedures. In fact, about 70% of patients with clinically suspected DVT are shown to be negative on instrumental investigations. Phlebography is still the gold standard in the diagnosis of peripheral DVT. Main phlebographic findings are: persistent filling defect; abrupt interruption of contrast in a vein; lack of opacification in all or some deep veins; flow diversion with opacification of collateral branches. At present, peripheral phlebography is performed when the other noninvasive exams (Color Doppler US and Duplex Doppler) are doubtful, technically limited or when thrombosis of innominate veins or superior vena cava, is suspected. Real-time US enables direct visualization of the limb proximal veins. The venous wall, the venous valves, the thrombus and its development, the anatomic variants, the perivenous structures which may impact on the normal physiology of venous return, are depicted. However, the distal veins of the leg and arm and deep veins (the iliac veins, the superficial femoral vein in the adductor canal) are not accurately visualized. The US findings in DVT include: the presence of echoes within the vascular lumen; the veins in axial scans are not compressible. Pulsed Doppler and duplex Doppler combine the morphologic and functional study. Injury caused by DVT at the valvular level (postphlebitic syndrome) is visualized. Primary deep vein thrombosis caused by valvular disorders (valvular aplasia) is identified. Inadequate superficial and perforating veins to be treated with surgery are mapped. Color Doppler US depicts directly superficial and deep limb veins combining the morphologic with the functional assessment represented by the visualization of the map of flow velocity and direction. Recently, a new diagnostic procedure, the color Doppler Energy (CDE) or Power Doppler has been introduced. Together with mean flow velocity and spectral variance, the signal energy or power is also analyzed. The CDE is independent of the US incidence angle, it does not shows the flow direction, detects particularly slow flows, early canalization of thrombi and non occlusive thrombosis. Color Doppler diagnosis of thrombosis is prompt because an area with absence of color is visualized. Collateral vessels and flow direction within them, is well depicted. Beside the site and extension of thrombosis, color Doppler US is able to directly visualize the distal end of the thrombus, which when floating is at high risk for embolism. CT allows an adequate study of the iliocaval axis and is useful if phlebography or color Doppler US are not diagnostic. Iliocaval thrombosis represents a not infrequent finding during abdominal CT. The thrombus appears as a hypodense mass encircled by the hyperdense rim of contrast medium.  相似文献   

2.
Prospective data on 202 consecutive patients who had a total of 123 total hip and ninety-four total knee arthroplasties were collected from two university medical centers. The findings of routine surveillance for deep venous thrombosis performed with ascending contrast venography were compared with those of surveillance with duplex ultrasonography complemented with color-flow Doppler imaging. All of the studies were performed between the third and seventh postoperative days. Of the 202 patients (342 extremities) who were examined, fifty-five (27 per cent) were found to have deep venous thrombosis; fifty-two (95 per cent) of the thrombi were in the calf and three (5 per cent) were in the proximal veins. All of the thrombi were clinically asymptomatic and all were nonocclusive, allowing passage of contrast medium around an intraluminal filling defect. Duplex ultrasonography with color-flow Doppler imaging correctly identified two of the three proximal thrombi and five of the fifty-two thrombi in the calf (sensitivity, 10 per cent). The sensitivity for the detection of thrombi in the calf was zero of sixteen at one of the institutions involved in the study and 14 per cent (five of thirty-six) at the other. There were two false-positive findings on ultrasonographic examination; one involved a proximal thrombus and one, a distal thrombus. We believe that the interinstitutional variability and insensitivity of duplex ultrasonography with color-flow Doppler imaging for the detection of asymptomatic deep venous thrombi in the calf after total joint replacement make it unreliable as a routine surveillance tool after total hip or knee arthroplasty.  相似文献   

3.
The efficacy of ultrasound compared with ascending venography for the detection of deep venous thrombosis immediately after total knee arthroplasty was assessed after a 2-year interval. One hundred thirty-seven patients were eligible for the study; however, 31 patients received only one of the screening methods and a color Doppler examination was inconclusive in six patients. Therefore, 100 patients had a Doppler examination and a venogram. Overall, the sensitivity of ultrasound was 85%, the specificity 97%, the positive predictive value 85%, the negative predictive value 97%, and the accuracy 95%. The sensitivity in the calf was 83%, in the popliteal vein 86%, and in the femoral vein 100%. Two years ago, the initial assessment of ultrasound for the detection of deep venous thrombosis after surgery in patients who had total joint arthroplasty revealed a 75% sensitivity, 99% specificity, 91% positive predictive value, 97% negative predictive value, and 97% accuracy. The sensitivity in the calf was 83%; the sensitivity in the popliteal vein was 40%; and the sensitivity in the femoral vein was 50%. After 2 years of using this screening test with one technician and one radiologist, an improvement with this noninvasive technique was shown. However, it was found that Doppler imaging is not as sensitive as venography for detecting calf thrombi. Any imaging technique should be validated by each institution to determine the validity of the instrument and the learning curve of the technician administering the examination.  相似文献   

4.
Characteristics of venous flow were studied in 81 normal legs and in 98 legs with varicose vein disorders. The change in the volume in the calf after calf muscle contractions was studied using the strain gauge technique with the patients in the erect position. During contractions of the calf muscle, the volume in the calf decreases, chiefly because of reduction of blood volume in the veins. After cessation of the contractions, there is a gradual return of volume to precontraction values. This was measured in seconds and called venous return time and in milliliters times 100 milliliters of tissue-1 times minutes-1 and called venous reflux flow. In normal persons, the venous return time was 21.9+/-6.7 (S.D.) seconds, and in patients with venous disorders, the corresponding time was 6.9+/-2.9 (S.D.) seconds. Venous reflux flow which was inversely correlated with the venous return time was 11.4+/-4.9 and 22.3+/-7.3 (S.D.), respectively. A good correlation was found between venous return time and venous pressure measurements. No age or sex differences were seen. In patients with superficial venous insufficiency, the venous return time and venous reflux time became normal when the diseased portion of the vein was compressed. In patients with insufficient perforating veins or damaged deep vein valves, external compression did not change venous flow characteristics. This indicates that the method can be used preoperatively to differentiate between primary and secondary varicose veins and, thus, influence the type of operation to be performed. The method can easily be applied for clinical purposes.  相似文献   

5.
BACKGROUND: Two different diagnostic strategies are used to perform compression (real-time) ultrasound for the diagnosis of clinically suspected deep-vein thrombosis. One is to examine the entire proximal venous system from common femoral to distal popliteal vein; the other is a limited examination of only the common femoral and the entire popliteal vein. The latter strategy, which is less time-consuming and requires less expensive equipment, is based on a strong impression from prospective studies using limited compression ultrasound that proximal vein thrombi always involve the common femoral or popliteal vein. This impression, which is supported by the demonstrated safety at long-term follow-up of not treating patients whose limited compression ultrasound is normal at presentation and then repeated within the next week, has not been tested in a formal study. Therefore, we reviewed a large series of venograms performed in consecutive patients with clinically suspected venous thrombosis to determine the distribution of venous thrombosis in symptomatic patients. METHODS: Venograms were performed using 150 mL of radiographic contrast material. Before the study, a panel of experts agreed on the standardized criteria for the assessment of venograms. Venograms were adjudicated blindly for the presence of deep vein thrombosis and to determine the distribution of proximal vein thrombosis and isolated calf-vein thrombosis, the size of proximal thrombi, and whether they were occlusive or nonocclusive. Subsequently, the duration of symptoms was related to the venographic findings. RESULTS: Five hundred sixty-two venograms from consecutive patients with a first episode of clinically suspected deep vein thrombosis were adjudicated. Of these, 20 (3.6%) were inadequate for interpretation. In the remaining 542, venous thrombosis was demonstrated in 189 instances (prevalence, 35%; 95% confidence interval, 31% to 39%) and were located in the proximal veins in 166 (88%; 95% confidence interval, 82% to 92%) venograms. Isolated calf-vein thrombosis was present in the remaining 23 (12%; 95% confidence interval, 8% to 18%) venograms. Proximal with concurrent calf thrombosis was detected in 164 (99%) of the 166 patients. Proximal thrombi involved only the popliteal vein in 16 (10%); the popliteal and superficial femoral veins in 70 (42%); and the popliteal, superficial, and common femoral vein in eight (5%); whereas thrombi involving the entire proximal deep venous system were detected in 58 (35%) venograms. Isolated thrombosis of the superficial femoral, common femoral, and iliac vein was not observed. Proximal venous thrombi were occlusive in 146 (88%) patients. No relation between the duration of symptoms and the extent or the occlusiveness of venous thrombi could be demonstrated. CONCLUSIONS: Most symptomatic patients have extensive occlusive proximal vein thrombosis at the time of presentation. Thrombi isolated to the superficial femoral or iliac vein were not observed in this large sample of consecutive patients. Our data support the use of the relatively simple, inexpensive, and rapid compression ultrasound method that limits the examination of the proximal veins to the common femoral and popliteal veins.  相似文献   

6.
PURPOSE: Upper-extremity thrombosis appears to be more frequent today, comprising about 2% of all deep venous limb thrombosis. Its severity depends on the type of possible complications, i.e., pulmonary embolism and post-thrombotic sequelae. In this retrospective series, we investigated both the predisposing factors and the evolution of upper-extremity deep venous thrombosis. METHODS: Forty-nine consecutive patients (24 men and 25 women, mean age 50.2 years) with upper extremity deep venous thrombosis documented by color Doppler ultrasonography (n = 47) or phlebography (n = 2) were included in the study. RESULTS: Clinical manifestations were mainly pain (81.6%) and edema (93.9%). Mean time between the onset of clinical signs and diagnosis was 7.2 days. Thrombosis involved humeral (26.5%), axillary (46.9%), subclavian (73.5%) and jugular (24.5%) veins. Causative factors were malignancies (32.7%), venous catheters (22.4%), deep venous thrombosis related to effort or thoracic outlet syndrome (22.5%) and thrombophilic states (8.2%). During the 6-month follow-up, six patients developed symptomatic pulmonary embolism (12.2%); one recurrence (2.2%) and 19 post-thrombotic sequelae such as residual edema (36.7%) were also observed. Initial therapy included heparin administration, principally subcutaneous low molecular weight heparins (n = 36/49). CONCLUSION: This series highlights the fact that upper-extremity deep venous thrombosis is mainly secondary to either malignancies or catheterization. Moreover, it confirms that color Doppler ultrasonography may be useful in the diagnosis of the disease and also underlines the high frequency of severe complications, i.e., pulmonary embolism and post-thrombotic sequelae. Finally, this study also demonstrates that low molecular weight heparins should be considered as the initial treatment of choice.  相似文献   

7.
A total of 60 patients from high risk group for deep vein thrombosis, which included the patients after major surgery and patients of primary venous diseases, were studied. Peripheral venous pressure measurement performed on 42 cases, detected deep vein abnormality in 6 patients (14.3%) only out of which 2 patients were designated as cases of deep vein thrombosis and 4 of chronic venous stasis syndrome. But phlebography detected deep vein thrombosis in 28 cases (46.6%) and other deep vein abnormalities in rest of the cases.  相似文献   

8.
Seventy-eight limbs of forty-eight patients undergoing total hip replacement were studied by roentgenographic phlebography, cuff-impedance phlebography, and 125I fibrinogen scanning. Compared with roentgenographic phlebography, cuff-impedance phlebography detected seven of ten thrombi in the thigh but none of nine thrombi in the calf and popliteal veins, giving an over-all accuracy of 80 per cent. The 125I fibrinogen scanning technique detected none of the ten thrombi in the thigh and seven of the nine in the calf and popliteal veins, giving an over-all accuracy of 78 per cent. Combining the results of the two techniques, fourteen of the nineteen thrombi were detected. Cuff-impedance phlebography appears to be a useful method for the diagnosis of thrombi in the thigh after hip surgery.  相似文献   

9.
While ultrasound has been well accepted as an accurate test for the diagnosis of both femoral and popliteal deep venous thrombosis (DVT), its role in the detection of calf DVT has been less clear. There have been variable results between studies in the accuracy of colour Doppler or compression sonographic techniques in demonstrating calf DVT. Many of these studies have suffered from high rates of technically inadequate examinations. Power Doppler (colour Doppler energy) has a higher sensitivity than conventional colour Doppler. It should therefore allow the detection of slow venous flow in patent vessels, that may not be demonstrated by conventional colour Doppler. This should decrease the number of technically inadequate examinations as well as decreasing the false-positive rate of the test. A prospective blinded reader study was undertaken comparing power Doppler to the gold standard venography, in the diagnosis of isolated calf deep venous thrombosis (DVT). Both examinations were successfully performed in 50 patients, in whom proximal DVT had been excluded by compression ultrasonography. Fifteen patients had positive evidence of an isolated calf DVT on the gold standard technique, venography. Power Doppler demonstrated a sensitivity of 100%, a specificity of 79%, a positive predictive value of 71% and a negative predictive value of 100%, in detecting an isolated calf DVT. There were no technically inadequate ultrasound examinations. Where venous flow is demonstrated, power Doppler is a highly accurate test in excluding a calf DVT. The specificity of the test, however, is limited, as the absence of flow does not always signify a DVT.  相似文献   

10.
Antiphospholipid antibody syndrome (APS) is now recognized as one of the most important causes of hypercoagulability. The most common site for venous thrombosis in APS is deep venous thrombosis of the lower extremities. Other sites of venous thrombosis include retinal veins, renal veins, and hepatic veins. The authors report a case of splenic vein thrombosis disclosing antiphospholipid syndrome in which also the cytolytic effect of aPL may play a role of "cofactor" in the genesis of thrombosis through the release of thromboplastin from the lysis of red cells, granulocytes and platelets, making them vulnerable to clearance by splenic macrophages. Important considerations are stressed about differential diagnosis, etiopathogenetic factors, therapy and follow-up of the patient.  相似文献   

11.
The pertrochanteric ossovenography brought important results on the etiology of combined obstructive edema of the lower limb after genital carcinoma. Its advantage in comparison with other methods of phlebography is the lack of embolic danger for the patient, its suitability even in thrombosis of the V. femoralis and the optimal contrast staining of venous system and anastomoses. The combined obstructive edema is characterized by a block of pelvic veins and a complete or incomplete block of lymph vessels. The combined obstructive edema depends only on the venous block as is demonstrated. A report on therapy and prognosis of 30 cases is given.  相似文献   

12.
PURPOSE: The high incidence of acute and chronic diseases of the venous system requires the application of reliable, non-invasive, low-cost methods in diagnosis and follow-up after therapy. MATERIAL AND METHODS: Current technology, principles of examination, and results of ultrasonography of the peripheral venous systems are reviewed. RESULTS: Since the mid 1980s, compression ultrasonography (US) has been introduced in the diagnosis of deep venous thrombosis. Doppler-US methods reach the hallmarks of venous imaging, particularly since the advent of color duplex US. In thrombosis, postthrombotic syndrome, and primary varicosis, color duplex US increasingly replaces the "gold standard" of phlebography as the imaging method of choice. Venous diseases of the neck, and of the upper and lower extremities are reliably recognized by color duplex US. New areas of application of Doppler and duplex-US include examinations of the venous system in patients in intensive care units, evaluation of transplanted organs, and the demonstration of blood flow in hemodialysis shunts. CONCLUSIONS: Color duplex US is useful in most imaging investigations of the peripheral veins. In view of cost development in the medical imaging sector, however, in which ultrasonography takes a major part, critical indication for the application of Doppler- and duplex-US in the diagnosis and follow-up of venous disease is out most importance.  相似文献   

13.
This paper describes the role of venous ultrasonography in the diagnosis of suspected deep venous thrombosis and pulmonary embolism. Inability to compress the common femoral or popliteal vein is usually diagnostic of a first episode of deep venous thrombosis in symptomatic patients (positive predictive value of about 97%). Full compressibility of both of these sites excludes proximal deep venous thrombosis in symptomatic patients (negative predictive value of about 98%). In patients with suspected deep venous thrombosis or in those who present with suspected pulmonary embolism but have a nondiagnostic lung scan, the subsequent risk for symptomatic venous thromboembolism is very low (<2% during 6 months of follow-up) provided that ultrasonography of the proximal veins remains normal in the course of 1 week (suspected deep venous thrombosis) or 2 weeks (suspected pulmonary embolism). Anticoagulation and further diagnostic testing can usually be safely withheld in these situations. Venous ultrasonography is much less reliable for the diagnosis of asymptomatic, isolated distal, and recurrent deep venous thrombosis than for the diagnosis of a first episode of proximal deep venous thrombosis in symptomatic patients. Clinical evaluation of the probability of deep venous thrombosis or pulmonary embolism, preferably by using a validated clinical model, complements venous ultrasonographic findings and helps to identify patients who would benefit from additional (often invasive) diagnostic testing. Thus, venous ultrasonography is thought to be a very valuable test for the diagnosis and management of patients with suspected deep venous thrombosis or pulmonary embolism.  相似文献   

14.
Acute deep venous thrombosis of the lower limb is a common and threatening condition whose clinical diagnosis is known to be unreliable. Sonography has gradually superseded venography as the primary diagnostic procedure. A review of the medical literature shows that sonography offers a high level of sensitivity and specificity in symptomatic patients but suffers from a lack of sensitivity at the calf level and in asymptomatic patients. Technologic progress, as well as increased operator experience, may improve sensitivity. Nevertheless, several critical issues remain unresolved, such as the significance of free-floating thrombi, the usefulness of calf and bilateral examination, the criteria that are essential to the diagnosis, the risk of compression sonography, and sonography's role in the direct detection of venous emboli.  相似文献   

15.
This study investigated the features of calf deep vein thrombosis (DVT) as a pulmonary embolic source. Fifty-eight lower limbs in 29 patients who were suspected of having DVT distal to the popliteal vein were screened by ultrasonography. Then, ascending venography was performed to confirm the diagnosis. Pulmonary embolism (PE) was diagnosed in suspected patients by use of pulmonary perfusion scanning or pulmonary angiography. Venography revealed calf DVT in 33 limbs in 28 patients. Of 28 patients, six had symptomatic PE. Thrombosis was found in the muscle veins in 18 limbs, the trunk veins in 11, and both veins in four. Isolated single vein thrombosis was found in the soleal vein in 14 limbs (42%), the posterior tibial vein in eight, the peroneal vein in two, and the gastrocnemius vein in two. The overall percentage of soleal vein thrombi was 61%. All six patients with symptomatic PE had isolated soleal vein thromboses. Calf DVT was a pulmonary embolic source when isolated thrombosis of the large soleal vein was more than 7 mm in diameter. Soleal veins were the most frequent and important location of calf DVT, suggesting that these were an occasional embolic source of critical PE.  相似文献   

16.
OBJECTIVE: To evaluate the safety of withholding anticoagulant treatment from patients with clinically suspected deep vein thrombosis but normal findings on compression ultrasonography. DESIGN: Compression ultrasonography was done with a simplified diagnostic procedure limited to the common femoral vein in the groin and the popliteal vein extending down to the trifurcation of the calf veins. Patients with normal ultrasonography findings at presentation were retested 1 week later. MAIN OUTCOME MEASURE: The incidence of venous thromboembolic complications during follow up for 6 months in patients in whom anticoagulant treatment was withheld on the basis of normal results on two ultrasonography tests 1 week apart. SETTING: University research centres in four hospitals. RESULTS: A total of 1702 patients were included in the study. Abnormal results on compression ultrasonography at presentation or at 1 week were found in 400 and 12 patients, respectively, for a prevalence of deep vein thrombosis of 24%. None of the patients were lost to follow up. Venous thromboembolic complications during the week of serial testing occurred in a single patient and in eight patients during 6 months' follow up, resulting in a cumulative rate of venous thromboembolic complications of 0.7% (95% confidence interval 0.3% to 1.2%). The mean number of extra hospital visits and additional tests required per initially referred patient was 0.8. CONCLUSION: It is safe to withhold anticoagulant treatment from patients with clinically suspected deep vein thrombosis who have a normal result on compression ultrasonography at the time of presentation and at 1 week.  相似文献   

17.
PURPOSE: Although the fact is well accepted that deep venous thrombosis (DVT) of the iliac, femoral, and popliteal veins can lead to the post-thrombotic (postphlebitic) syndrome, the significance of isolated calf DVT on the development of late venous sequelae and physiologic calf dysfunction is unknown. The purpose of this study was to review the outcome of 58 limbs with isolated calf DVT and report the clinical, physiologic, and imaging results up to 6 years after the onset of DVT. METHODS: The study consisted of 58 limbs of 54 patients in whom isolated calf vein DVT was diagnosed between 1990 and 1995. Proximal propagation of clot, lysis of thrombi, and development of symptomatic pulmonary emboli were examined. Of the patients, 28 received anticoagulation therapy, and 26 did not, but they had follow-up with serial duplex scans. At late follow-up 1 to 6 years later (median, 3 years), 23 patients were examined for the post-thrombotic syndrome, and all 23 underwent clinical examination, color-flow duplex scanning, and air plethysmography. RESULTS: Proximal propagation of DVT from the calf veins into the popliteal or thigh veins occurred in 2 of 49 cases (4%) within 2 weeks of diagnosis. No patient had clinically overt pulmonary emboli develop regardless of whether anticoagulation therapy was received or not. The most common site for calf DVT was the peroneal vein (71%). Complete lysis of calf thrombi was found in 88% of the cases by 3 months. At 3 years, 95% of the patients were either asymptomatic or mildly symptomatic, and 5% had discoloration of the limb. No ulcers occurred. By air plethysmography, physiologic abnormalities were found in 27% of the cases, which was not significantly different from normal controls. Valvular reflux by duplex scanning of the calf vein segment with DVT was found in 2 of 23 cases (9%). However, reflux in at least one venous segment not involved with DVT was found in 7 of 23 cases (30%), which was higher than, but not statistically different from, normal controls, with reflux occurring in 5 of 26 cases (19%). CONCLUSIONS: Isolated calf vein DVT leads to few early complications (ie, clot propagation, pulmonary emboli) and few adverse sequelae at 3 years. The peroneal vein is most commonly involved and should be a part of the routine screening for DVT. Lysis of clot usually occurs by 3 months. Although valvular reflux rarely is found in the affected calf vein at 3 years, reflux may be found in adjacent uninvolved veins in approximately 30% of the cases. The question of whether this will lead to future sequelae, such as ulceration, will require longer follow-up.  相似文献   

18.
MD Iafrati  HJ Welch  TF O'Donnell 《Canadian Metallurgical Quarterly》1997,25(6):995-1000; discussion 1000-1
PURPOSE: Early results of subfascial endoscopic perforator surgery (SEPS) were examined. Data on ulcer healing, complications, and costs are presented. METHODS: Data were prospectively collected for all patients who underwent SEPS at our institution. A concurrent control group was not available because primary open perforator ligation is no longer performed at our hospital. Preoperative assessment included duplex scanning (valve closure times and perforator mapping), plethysmography, and phlebography. Completeness of therapy was assessed with postoperative duplex mapping of perforating veins. Clinical status was monitored after surgery, and actual costs, including equipment, personnel, and facilities management, are reported. RESULTS: Eighteen procedures were performed in 15 patients (mean age, 52 years; range, 42 to 65 years). Two patients underwent bilateral SEPS, and one patient underwent a second procedure on the same leg. Active ulceration (class 6) was present in 14 of 18 limbs (78%), recently healed ulcers (class 5) in two of 18 (11%), and lipodermatosclerosis with edema (class 4) in two. Deep venous insufficiency was present in 14 of 18 (78%). The number of perforating veins ligated per leg ranged from 0 to 12 (mean, 4.3). Follow-up ranged from 3 to 64 weeks (mean, 22 weeks). Complete ulcer healing occurred in eight of 14 limbs (57%) at a mean of 14 weeks. Reduction in ulcer size was noted in four of 14 (29%), and two limbs were not improved. There were no new ulcers. Residual perforating veins were noted in four of 18 limbs. None of the limbs with residual perforating veins had complete healing of ulceration. Operating room costs were higher than those associated with limited-incision open perforator ligation ($2570 vs $1883). CONCLUSION: These preliminary data suggest that when used as part of a treatment plan to correct deep and superficial venous insufficiency SEPS results in a high rate of wound healing, with no recurrent ulceration in this series. Increased operating room costs associated with longer operations and greater disposable expenses will likely be overcome by shortened length of stay and diminished wound complications. These findings emphasize the importance of ligating all incompetent perforating veins, as ulcer healing was never achieved when residual perforating veins were found at follow-up.  相似文献   

19.
Venous thromboses of the pelvic veins and the veins of the lower limbs were found in 40% of the post mortems carried out on 1350 adults during 1974. The thromboses were bilaterally located in the calf veins in the vast majority of cases. The predominating underlying diseases of patients with thrombosis were malignant neoplasia or cardiovascular diseases. 319 cases (23.5%) showed massive pulmonary embolism. The pulmonary embolism had taken a fulminating fatal course in 7.8% of cases. Thromboses of the lower limb veins seem to have a higher tendency to become mobilized to cause fatal pulmonary embolism than thromboses occurring in other sites. A significantly higher incidence of venous thrombosis, as well as of pulmonary embolism, was found in higher age groups and in female patients; the prognosis is, moreover, grave in these cases. A significant increase in the incidence of venous thromboses and pulmonary embolism-especially those with a rapidly fatal course-has been registered over the past years as compared with previous investigations.  相似文献   

20.
OBJECTIVES: Either venous or arterial thrombosis is a potentially life-threatening event and existing diagnostic modalities are inadequate to diagnose and to determine the morphology of the evolving thrombus. Thus development of a noninvasive imaging agent that can detect clot location remains a critical and unmet need in nuclear diagnostic medicine. The present study was undertaken to determine the potential of platelet GPIIb/IIIa receptors compared with direct thrombin inhibitors, in the detection of venous and arterial clots. METHODS: Initially, the validity of exploiting the degree and extent of specific uptake and retention of a potent GPIIb/IIIa receptor antagonist in venous and in arterial thrombus was confirmed in vitro in artificially created arterial- or venous-type clots, using the radiolabeled antagonist, 3H-DMP728. This was followed by comparing the in-vivo clot/blood distribution of various technetium-99m (99mTc)-labeled, DMP728-derived, GPIIb/IIIa receptor antagonists and of thrombin inhibitors, over time, in mixed arterial/venous or venous clots in arteriovenous shunt and in venous clot models in dogs. In addition, we performed noninvasive single-photon emission tomographic imaging of the venous clot in a deep vein thrombosis model in dogs. RESULTS: Our data confirmed that potency for the platelet GPIIb/IIIa receptors was maintained after radiolabeling of the parent active GPIIb/IIIa receptor antagonists. DMP728 demonstrated a relatively greater affinity for activated than for unactivated human platelets, which might be essential for attaining an optimal thrombus/blood (target/background) distribution ratio and the optimal detection of small clots (i.e. greater sensitivity). CONCLUSIONS: These data suggest a potential utility of 99mTc-GPIIb/IIIa receptor antagonists, but not of direct thrombin inhibitors, in the diagnosis of venous clots in deep vein thrombosis, pulmonary embolism and arterial thromboembolic disorders including stroke and coronary and peripheral artery thrombotic disorders.  相似文献   

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