Diagnostic Imaging Pathways - Deep Venous Thrombosis (Leg)
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This pathway provides guidance on the imaging of adult patients with suspected lower limb deep venous thrombosis.
Date reviewed: January 2012
Date of next review: January 2015
Published: January 2012
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The relative radiation level (RRL) of each imaging investigation is displayed in the pop up box.
| SYMBOL | RRL | EFFECTIVE DOSE RANGE |
 | None | 0 |
 | Minimal | < 1 millisieverts |
 | Low | 1-5 mSv |
 | Medium | 5-10 mSv |
 | High | >10 mSv |
Images
Image GalleryNote: These images open in a new page | ||
|---|---|---|
| 1a |  |
Leg Deep Vein Thrombosis Image 1a and 1b (Doppler Ultrasound): Acute thrombosis is indicated by the distended and hypoechoic lumen of the common femoral and external iliac veins with no flow. |
| 1b |  |
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Teaching Points
Teaching Points
- Clinical prediction rules (eg Wells Criteria) may be used to categorise patients into low, medium or high risk
- Low risk and negative serum D-Dimer effectively excludes DVT
- Medium and high risk patients should undergo doppler ultrasound without D-Dimer estimation
- Ultrasound is highly sensitive for proximal lower limb deep vein thrombosis
- US is less sensitive for deep calf vein thrombosis and for iliac vein thrombosis
- After a negative doppler ultrasound, follow-up US in patients with high clinical suspicion may be indicated to exclude a calf thrombosis that is propagating proximally
ddimer
D-Dimer
- Is formed as a result of plasmin generated degradation of thrombin and is therefore a marker of the presence of thrombus
- There are various qualitative and quantitative assays available for D-Dimer but in general they have a high sensitivity and negative predictive value for the presence of thrombus 10,11
- Of the various assays, the quantitative enzyme linked immunosorbent assay (ELISA) has the best negative likelihood ratio and is significantly superior to non-ELISA assays for excluding the presence of deep vein thrombosis.The sensitivity is higher for proximal, compared to distal DVT 12,13
- A negative quantitative ELISA D-Dimer result is as diagnostically useful for excluding DVT as a negative duplex Doppler ultrasound 12
- If a patient is assessed, based on pre-test probability as unlikely to have leg DVT returns a negative D-Dimer result, there is generally considered to be no requirement for a Doppler ultrasound 4,12
- An elevated D-Dimer level is non-specific for venous thromboembolism, and diagnostic imaging is required to confirm the presence of disease 14
- D-Dimer has a limited role in hospitalised patients, and ultrasonography should be performed if deep venous thrombosis is suspected
us
Ultrasound Including Doppler
- Most accurate non-invasive test for the diagnosis of a first symptomatic proximal deep vein thrombosis 5,6
- Involves a combination of 6
- Compression ultrasonography - starting at the inguinal ligament and generally extending to the venous trifurcation in the calf
- Doppler imaging - particularly useful where compressibility is difficult to assess
- Advantages of ultrasound 7,8
- Excellent sensitivity for proximal vein thrombosis (97%) 5
- Ability to depict anatomical variants (e.g. duplicated venous segments) and alternative causes of symptoms
- Non-invasive
- No exposure to ionising radiation
- Does not involve the use of contrast agent
- Relatively inexpensive
- Limitations of ultrasound 6,7
- Venous compressibility may be limited by patient characteristics such as obesity, oedema, and tenderness
- False positives may occur due to extrinsic compression of a vein by pelvic mass or other perivascular pathology
- A negative ultrasound scan in moderate to high risk patients does not reliably exclude the diagnosis of deep vein thrombosis 12
- Less sensitive for detecting distal vein thrombosis (73% sensitivity) and in detecting thrombosis in iliac veins 5
- Serial ultrasound is used to detect those DVTs that were isolated distally in the calf initially and undetected but which subsequently extend into the more proximal veins 7
- Isolated distal calf DVTs rarely lead to significant embolic events 9
wells
Wells Criteria
- This clinical prediction rule is designed to increase the probability of an accurate diagnosis of deep venous thrombosis 1,2,3,4
- Active cancer (patient receiving treatment for cancer within the previous 6 months or currently receiving palliative treatment (1 point)
- Paralysis, paresis, or recent plaster immobilisation of the lower extremities (1 point)
- Recently bedridden for 3 days or more, or major surgery within the previous 12 weeks requiring general or regional anaesthesia (1 point)
- Localised tenderness along in the distribution of the deep venous system (1 point)
- Entire leg swollen (1 point)
- Calf swelling at least 3cm larger than that on the asymptomatic side (measured 10cm below tibial tuberosity) (1 point)
- Pitting oedema confined to the symptomatic leg (1 point)
- Collateral superficial veins (nonvaricose) (1 point)
- Previously documented DVT (1 point)
- Alternative diagnosis at least as likely as DVT (-2 points)
Score of 2 or higher = DVT likely
Score of less than 2 = DVT unlikely
References
References
References are graded from Level I to V according to the Oxford Centre for Evidence-Based Medicine, Levels of Evidence. Download the document
- Wells PS, Anderson DR, Bormanis J, et al. Value of assessment of pretest probability of deep-vein thrombosis in clinical management. Lancet. 1997;350:1795-8. (Level II evidence). View the reference
- Perrier A, Desmarais S, Miron M-J, et al. Non invasive diagnosis of venous thromboembolism in outpatients. Lancet. 1999;353:190-5. (Level II evidence). View the reference
- Wells PS, Hirsh J, Anderson DR, et al. Accuracy of clinical assessment of deep-vein thrombosis. Lancet. 1995;345:1326-30. (Level II evidence). View the reference
- Wells PS, Anderson DR, Rodger M et al. Evaluation of D-dimer in the diagnosis of suspected deep-vein thrombosis. N Engl J Med. 2003;349:1227-35 (Level II evidence). View the reference
- Kearon C, Julian JA, Math M, et al. Noninvasive diagnosis of deep venous thrombosis. Ann Intern Med. 1998;128:663-77. (Review article)
- American Thoracic Society. The diagnostic approach to acute venous thromboembolism: clinical practice guidelines. Am J Respir Crit Care Med. 1999;160:1043-66. (Review article)
- Keeling DM, Mackie IJ, Moody A, Watson HG; The Thrombosis and Haemostasis task force of the British Committee for Standards in Haematology. The diagnosis of deep vein thrombosis in symptomatic outpatients and the potential for clinical assessment and D-dimer assays to reduce the need for diagnostic imaging. Br J Haematol. 2004;124:15-25. (Review article)
- Fraser JD, Anderson DR. Deep venous thrombosis: recent advances and optimal investigation with US. Radiology. 1999;211:9-24. (Review article)
- Philbrick JT, Becker DM. Calf deep venous thrombosis. A wolf in sheep’s clothing? Arch Intern Med. 1988;148:2131-8. (Analytical review)
- Freyburger G, Trillaud H, Labrouche S, et al. D-dimer strategy in thrombosis exclusion - a gold standard study in 100 patients suspected of deep venous thrombosis or pulmonary embolism: 8 DD methods compared. Thromb Haemost. 1998;79:32-7. (Level II evidence). View the reference
- Brill-Edwards P, Lee A. D-dimer testing in the diagnosis of acute venous thromboembolism. Thromb Haemost. 1998;82:688-94. (Review article)
- Stein PD, Hull RD, Patel KC, et al. D-Dimer for the exclusion of acute venous thrombosis and pulmonary embolism: a systematic review. Ann Intern Med. 2004;140:589-602. (Level I evidence). View the reference
- Goodacre S, Sampson FC, Sutton AJ, Mason S, Morris F. Varaition in the diagnostic performance of D-dimer for suspected deep vein thrombosis. Q J Med. 2005;98:513-27 (Level II evidence). View the reference
- Ho WK, Hankey GJ, Lee CH, Eikelboom JW. Venous thromboembolism: diagnosis and management of deep venous thrombosis. Med J Aust. 2005;182:476-81. (Review article)
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