Detection Of 111-Indium Labelled Platelets In Experimental Venous Thrombosis

1981 ◽  
Author(s):  
R P Grimley ◽  
J Fejfar ◽  
R J Hawker ◽  
Z Drolc

Successful detection of Indium-lll-oxine labelled platelets in venous thrombi offers a new meth od of diagnosis of venous thrombosis. Femoral vein thrombosis was established in 20 dogs by a combination of partial venous occlusion and vein electrification. In this model, thrombosis is first detectable on venography after 48 hours. Autologous labelled platelets were re-injected into each dog; a sham operation having been performed on the opposite femoral vein. Bilateral venography was performed 2 days and 7 days post-operatively and each dog was sacrificed after removal of femoral veins. Isotopic detection of venous thrombosis was determined by comparison of scintillation counts over each femoral vein daily for one week.Ratios of isotope counts between abnormal and normal legs indicated thrombus formation in 8 out of 10 dogs with known thrombi;two false negative results were due to hematoma formation. The mean duration of detection was 2.5 days. The counts were higher over venous thrombi in 3 out of 4 dogs who received platelet labelling prior to thrombus formation. Here, the mean duration of detection was 4 days. In 6 control animals, where veins were partially occluded only, counts were similar in each leg.

1991 ◽  
Vol 6 (4) ◽  
pp. 241-248 ◽  
Author(s):  
Håkan Ahlström ◽  
Stefan Nilsson ◽  
Göran Hellers

One-hundred-and-eleven consecutive patients who were referred for routine phlebography because of clinically suspected deep vein thrombosis (DVT) were also investigated with a new, simplified, computerized strain-gauge plethysmograph (Phlebotest, Eureka AB). An occlusion plethysmograph curve was obtained from each leg simultaneously. Four different numerical parameters were defined and determined from this curve. These parameters were correlated with the phlebographic diagnosis. Three of the parameters of the plethysmograph curve correlated well with the phlebographic diagnosis, which proved correct in 54 patients without DVT, including two false negative cases, and in 12 patients with thrombosis. In 45 patients, plethysmography alone was not sufficient to establish a diagnosis. The plethysmograph described is easy to handle and is suggested for use in selecting those patients, with or without thrombosis, who do not require supplementary phlebography.


VASA ◽  
2006 ◽  
Vol 35 (1) ◽  
pp. 41-44 ◽  
Author(s):  
Klein-Weigel ◽  
Pillokat ◽  
Klemens ◽  
Köning ◽  
Wolbergs ◽  
...  

We report two cases of femoral vein thrombosis after arterial PTA and subsequent pressure stasis. We discuss the legal consequences of these complications for information policies. Because venous thrombembolism following an arterial PTA might cause serious sequel or life threatening complications, there is a clear obligation for explicit information of the patients about this rare complication.


1974 ◽  
Vol 31 (02) ◽  
pp. 273-278
Author(s):  
Kenneth K Wu ◽  
John C Hoak ◽  
Robert W Barnes ◽  
Stuart L Frankel

SummaryIn order to evaluate its daily variability and reliability, impedance phlebography was performed daily or on alternate days on 61 patients with deep vein thrombosis, of whom 47 also had 125I-fibrinogen uptake tests and 22 had radiographic venography. The results showed that impedance phlebography was highly variable and poorly reliable. False positive results were noted in 8 limbs (18%) and false negative results in 3 limbs (7%). Despite its being simple, rapid and noninvasive, its clinical usefulness is doubtful when performed according to the original method.


1981 ◽  
Author(s):  
E Briët ◽  
M J Boekhout-Mussert ◽  
L H van Hulsteijn ◽  
C W Koch ◽  
H W C Loose ◽  
...  

Fifty-three patients were examined because of suspected deep venous thrombosis, by means of clinical examination, Doppler ultrasound and venography. Eighty-two legs were examined with all three methods. Venography was positive in 40 and normal in 42. The clinical examination was false positive in 4 legs and false negative in 6. The Doppler ultrasound studies gave false positive results in 3 legs and false negative results in 6. These results are better than those reported in the literature probably because the thrombosis extended to the popliteal vein or the more proximal veins in 38 of the 40 legs with deep vein thrombosis. This high percentage of upper leg vein thrombosis can be explained by the fact that 47 of the 53 patients were ambulant when they developed the signs and symptoms of thrombosis. It is concluded, that the clinical examination and Doppler ultrasonography can be used to diagnose deep vein thrombosis in ambulant patients in our clinic. We presume that the findings reported in the literature cannot be used indiscriminately as a basis for diagnostic strategies in other hospitals because of widely varying categories of patients, referral patterns and diagnostic criteria that are virtually impossible to standardize.


2006 ◽  
Vol 96 (08) ◽  
pp. 149-153 ◽  
Author(s):  
Sang Kim ◽  
Dong Lee ◽  
Choong Kim ◽  
Hyun Moon ◽  
Youngro Byun

SummaryThe use of heparin as the most potent anticoagulant for the prevention of deep vein thrombosis and pulmonary embolism is nevertheless limited, because it is available to patients only by parenteral administration. Toward overcoming this limitation in the use of heparin, we have previously developed an orally active heparin-deoxycholic acid conjugate (LMWH-DOCA) in 10% DMSO formulation. The present study evaluates the anti-thrombogenic effect of this orally active LMWH-DOCA using a venous thrombosis animal model with Sprague-Dawley rats. When 5 mg/kg of LMWH-DOCA was orally administered in rats, the maximum anti-FXa activity in plasma was 0. 35 ± 0. 02, and anti-FXa activity in plasma was maintained above 0. 1 IU/ml [the minimum effective anti-FXa activity for the prevention of deep venous thrombosis (DVT) and pulmonary embolism (PE)] for five hours. LMWH-DOCA (5 mg/kg, 430 IU/kg) that was orally administered reduced the thrombus formation by 56. 3 ± 19. 8%;on the other hand, subcutaneously administered enoxaparin (100 IU/kg) reduced the thrombus formation by 36. 4 ± 14. 5%. Also, LMWH-DOCA was effectively neutralized by protamine that was used as an antidote. Therefore, orally active LMWH-DOCA could be proposed as a new drug that is effective for the longterm prevention of DVT and PE.


2019 ◽  
Vol 119 (06) ◽  
pp. 992-999 ◽  
Author(s):  
Shana A. Shaya ◽  
Dhulfiha Muzafar Gani ◽  
Jeffrey I. Weitz ◽  
Paul Y. Kim ◽  
Peter L. Gross

Background Deep vein thrombosis (DVT) can lead to pulmonary embolism (PE), but the mechanisms responsible for this progression are unknown. Previously, we showed that inhibition of thrombin-mediated activation of factor (F) XIII promotes venous thrombus stability in a murine model. Aim In this study, we investigate the consequence of attenuating fibrinolysis, using FXIII, α2-antiplasmin (α2-AP) or ε-aminocaproic acid (EACA) supplementation, on clot lysis and venous thrombus stability using the same mouse model. Methods In vitro plasma clot lysis assay shows that EACA and α2-AP but not FXIII, inhibit fibrinolysis. Ferric chloride induced thrombi in the femoral vein of mice. After thrombus formation, mice received saline, EACA, α2-AP or FXIII, with or without dalteparin or dabigatran. Thrombus sizes and embolization over 2 hours were visualized using intravital videomicroscopy. Lungs were sectioned to quantify emboli presence via histology. Results The change in thrombus size over time was significantly greater after EACA treatment, but not FXIII or α2-AP supplementation, compared with saline. α2-AP-supplementation did not alter thrombus stability. Thrombi were more stable following EACA treatment and FXIII supplementation as evidenced by less embolic events and PE burden, even when they were anticoagulated with either dalteparin or dabigatran. Conclusion FXIII supplementation stabilized venous thrombi, even in the presence of anticoagulants, and did not alter thrombus size. Supplemental FXIII may be useful to stabilize DVT and be an alternative adjunctive treatment to minimize PE, even when anticoagulants are used.


1988 ◽  
Vol 29 (6) ◽  
pp. 649-652 ◽  
Author(s):  
L. Kjær ◽  
S. Winter Christensen ◽  
Aa. Vestergaard ◽  
A. Bjerg-Nielsen ◽  
P. Wille-Jørgensen

Contact thermography is a non-invasive, easily handled, and inexpensive investigation for the diagnosis of deep venous thrombosis (DVT) in the lower limbs. In this study 56 patients with total hip replacement were screened for DVT by contact thermography, using bilateral ascending phlebography as reference procedure. Examinations were performed on the seventh postoperative day. All thermograms were evaluated blindly and independently at the end of the study. Phlebography revealed unilateral DVT in six patients. Only two had corresponding findings at thermography, giving four false negative results. Moreover, 14 false positive thermograms were found. Based on the number of legs investigated, the nosographic sensitivity and specificity thus were 33 and 87 per cent, respectively. It is concluded that contact thermography is of no value as a screening test for DVT following major hip surgery.


2020 ◽  
Vol 58 (10) ◽  
pp. 1697-1705
Author(s):  
Federica Braga ◽  
Erika Frusciante ◽  
Simona Ferraro ◽  
Mauro Panteghini

AbstractBackgroundDefinitive data to establish if the use of the WHO International Standard (IS) 03/178 as a common calibrator of commercial measuring systems (MSs) has improved the harmonization of serum total folate (tFOL) measurements to a clinically suitable level are lacking. Here, we report the results of an intercomparison study aimed to verify if the current inter-assay variability is acceptable for clinical application of tFOL testing.MethodsAfter confirming their commutability, the IS 03/178 and National Institute for Standards and Technology SRM 3949 L1 were used for evaluating the correctness of traceability implementation by manufacturers and the MSs trueness, respectively. The inter-assay agreement was verified using 20 patient pools. The measurement uncertainty (U) of tFOL measurements on clinical samples was also estimated. An outcome-based model for defining desirable performance specifications for bias and imprecision for serum tFOL measurements was applied.ResultsThe majority of evaluated MSs overestimated the WHO IS value of +5% or more with the risk to produce an unacceptably high number of false-negative results in clinical practice. The mean inter-assay CV on all pools and on those with tFOL values >3.0 μg/L (n = 15) was 12.5% and 7.1%, respectively. In neither case the goal of 3.0% was fulfilled. The residual bias resulted in an excessive U of tFOL measurement on clinical samples.ConclusionsThe implementation of traceability of tFOL MSs to the WHO IS 03/178 is currently inadequate, resulting in an inter-assay variability that does not permit the use of a common threshold for detecting folate deficiency.


PEDIATRICS ◽  
1984 ◽  
Vol 74 (6) ◽  
pp. 1065-1068 ◽  
Author(s):  
K. L. Tan ◽  
A. Loganath ◽  
A. C. Roy ◽  
H. H. Goh ◽  
S. M. Karim ◽  
...  

Umbilical cord plasma α-fetoprotein (AFP) values were determined in 127 infants with hyperbilirubinemia (56 glucose-6-phosphate dehydrogenase (G-6-PD) deficient and 71 G-6-PD normal) and 136 control subjects (73 G-6-PD deficient and 63 G-6-PD normal). The mean α-fetoprotein value of 173 ± 35.2 (SD) mg/L for the group of infants with hyperbilirubinemia was significantly greater than that (122 ± 21.7 mg/L) for the control infants (P < .001). G-6-PD status and sex did not significantly affect the α-fetoprotein values. Using an α-fetoprotein level of 130 mg/L as a "cut-off" value, the incidence of false-positive results was 25.5% and the incidence of false-negative results was 11.8%. This test can be used as a screening procedure to detect infants at high risk for hyperbilirubinemia.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1246-1246
Author(s):  
Lisa J Saldanha ◽  
Anthony KC Chan ◽  
Peter L Gross

Abstract Abstract 1246 Background: Thrombus stability influences the progression of deep vein thrombosis to a potentially fatal pulmonary embolism (PE) event. Anticoagulants are clinically administered to treat venous thrombosis. However, the effect of anticoagulants on thrombus stability remains unknown. Objective: We developed a novel intravital mouse model to explore the hypothesis that administration of clinical anticoagulants would decrease early thrombus stability, thereby potentially increasing PE risk. Methods: The trachea and jugular vein were cannulated, and the femoral vein isolated, in wild type C57/Bl6 female mice. Platelets were labeled in vivo using anti-mouse CD41 Fab fragments conjugated to Alexa Fluor-488. A 1 × 2 mm filter paper strip, saturated in 4% ferric chloride, was applied to the femoral vein for 5 minutes to induce thrombus formation. Wide-field fluorescent microscopy was used to quantify thrombus stability. Stability was related to the number of embolic events and loss of platelet intensity captured downstream of the thrombus at 5, 15, 30, 45, and 60 minutes post thrombus formation. Results: The mean number of embolic events and loss of platelet intensity decreased over time in wild type mice (n = 12). This suggested that thrombus stability increases over time. Anticoagulants were administered via a jugular vein catheter, at 12 minutes post thrombus formation, to assess impact on embolization. The anticoagulants examined were hirudin (8U/g mouse body weight), unfractionated heparin (UFH) (0.1U/g), a covalent antithrombin-heparin complex (ATH) (0.08U/g), and fondaparinux (0.1μg/g). We observed an overall a) increase in the number of embolic events and b) increase in platelet intensity lost over time in mice injected with hirudin (n = 12) and UFH (n = 12) when compared to untreated wild type control mice. The total number of embolic events occurring over one hour substantially increased in the hirudin-treated group (p = 0.09), which was also associated with an overall increase in total platelet intensity (p = 0.08), compared to untreated control mice. In addition, there was an increase in the total number of embolic events compared to the UFH-treated group (p = 0.09). Administration of hirudin, a direct thrombin inhibitor (DTI), and UFH, an indirect thrombin inhibitor, could result in decreased venous thrombus stability. However, it appears that the DTI is associated with greater thrombus instability. In the ATH-treated group (n = 12), an increase in embolic events at 15 minutes was observed, followed by a decrease in embolization. ATH could initially disrupt thrombus stability through inhibition of fibrin-bound thrombin, before acting in a stabilizing manner. Administration of fondaparinux (n = 6), an indirect factor-Xa inhibitor, demonstrated an overall decrease in embolic events and platelet intensity lost over time. When compared to control groups, there was a significant decrease in total number of embolic events and total amount of platelet intensity lost in the fondaparinux group (p < 0.05). Use of a factor-Xa inhibitor appears to enhance thrombus stability more effectively in comparison to direct and indirect thrombin inhibitors. Conclusion: Use of anticoagulants that inhibit thrombin predominantly could decrease early thrombus stability and potentially increase the likelihood of a PE event. Disclosures: No relevant conflicts of interest to declare.


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