A computerised system of screening for deep venous thrombosis

Laverick,; McGivern, R. C.; Brown, J. G.; Birkmyre, JS; Kernohan, George; Croal, S. A.; McNally, Martin; Mollan, Rab

doi:10.1016/0049-3848(92)90190-l

Cited by 12 publications

(9 citation statements)

References 12 publications

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“…More importantly the values calculated for V~ and V o in the non-occluded case (model V~ = 2.49%, model V o = 46.5 ml 100 m1-1 min -1) were within the normal limits expected for a clot-free patient and agree well with the mean values obtained from clinical studies (mean V~ = 3.05%, mean V o = 51 ml 100 ml-1 min-1 ) over 413 patients (LAVERICK et al, 1992;CROAL et al, 1993;MCNALLY et al, 1993b).…”

Section: Discussionsupporting

confidence: 60%

“…In addition, the invasive procedure and dye-compound can produce local venospasm (MCLACHAN et al, 1979), so the venography does not always provide a completely accurate picture of the clot and vessel geometry. Despite these reservations with regard to the accuracy of the venography in defining clot sizes, the broad agreement between the results of the numerical simulation and clinical studies comparing SGP and venography is encouraging (LAVERICK et al, 1992;CROAL et al, 1993;MCNALLY et al, 1993b). The numerical simulations predict that the SGP technique should be able to detect non-occlusive clots in the large proximal veins, as well as complete occlusions of calf veins.…”

mentioning

confidence: 77%

“…This equipment was cumbersome and was eventually replaced by electrical impedance systems, then strain gauges, to measure calf volume (CRAMER et al, 1983a;SINTON et al, 1988;WARD et al, 1989;LAVERICK et al, 1992). Clinical trials using strain gauge plethysmography (SGP) have shown that the technique detects DVT with a high sensitivity and good specificity and such systems are available commercially (LAVERICK et al, 1992;CROAL et al, 1993;MCNALLY et al, 1993a). in the SGP test, the change in calf volume with time is measured during cuffinflation and deflation.…”

Section: Introductionmentioning

confidence: 98%

“…When the cuff is subsequently deflated, blood leaves the limb and the volume change can be a method of assessing venous outflow. Although initially developed to assess arterial circulation, the outflow characteristic allows the detection of DVT since these clots obstruct, and therefore prolong outflow (CRAMER et al, 1983a;LAVERICK et al,1992).…”

Section: Introductionmentioning

confidence: 99%

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Numerical model of deep venous thrombosis detection using venous occlusion strain gauge plethysmography

Turner

McNally

O’Connell³

et al. 2000

Med. Biol. Eng. Comput.

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Strain gauge plethysmography (SGP) is a non-invasive method used in the detection of deep venous thrombosis (DVT). The technique is based on the measurement of calf volume changes in response to venous occlusion by a thigh cuff, the volume changes reflecting the rates of arterial inflow and venous outflow. A numerical model of the blood circulation within the limb and the response of this to a SGP test has been derived, based on treating the different parts of the circulatory system in the leg as resistance and capacitance elements. The simulation results were compared with clinical studies and support the ability of SGP to detect non-occlusive clots of more than 50-60% of the lumen, as well detecting calf vein occlusion. The non-linear behaviour of the venous compliance with intra-luminal pressure appears to be a particularly important factor within the model. In addition, increases in venous tone due to post-operative venospasm were shown to be a potential source of false positive results.

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Section: Discussionsupporting

confidence: 60%

mentioning

confidence: 77%

Section: Introductionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Numerical model of deep venous thrombosis detection using venous occlusion strain gauge plethysmography

Turner

McNally

O’Connell³

et al. 2000

Med. Biol. Eng. Comput.

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“…The reported sensitiv ity and specificity range from 95-100% and 80-100%, respectively (Table 2). Like IPG, SGP is sensitive and specific in proximal vein thrombosis, but lacks accuracy in calf vein thrombosis [60][61][62][63][64][65][66][67].…”

Section: Strain-gauge Plethysmography (Sgp)mentioning

confidence: 99%

Diagnosis of deep vein thrombosis, an overview

Janssen

Wollersheim

Nováková

et al. 1996

The Netherlands Journal of Medicine

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A bstractBecause clinical signs and symptoms are unreliable the diagnosis of deep vein thrombosis (DVT) should be objectified. Advantages and disadvantages of contrast venography, plethysmography, ultrasound techniques, fibrino gen leg scanning, computer-assisted tomography, magnetic resonance imaging and blood tests are discussed. In patients with a first event of suspected DVT non-invasive methods like serial plethysmography or ultrasound testing are sensitive and specific enough to make a treatment decision. It is safe to withhold anticoagulants if the test remains normal within 1 week. In patients with suspected recurrent DVT new non-invasive techniques are being tested, but up to now the definitive objective diagnostic test continues to be contrast venography. In first period as well as in recurrent DVT D-Dimer testing could be an additional test to exclude active thromboembolism.

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