DVT?

USSRU consensus 2018

Swollen painful leg; the answer starts or withholds anticoagulation tonight.

Answer the surgeon

Start anticoagulation; iliofemoral extent may prompt specialist evaluation, while selected patients with isolated calf DVT may be managed with serial imaging rather than immediate anticoagulation.

Your answer must state:

Non-compressibility — the primary direct criterion in accessible venous segments
Most proximal and distal extent by segment: common femoral, femoral, popliteal, calf veins
Occlusive vs non-occlusive
Acute venous thrombosis vs chronic postthrombotic change vs indeterminate
A free-floating proximal tail

Key and direct findings

1.Vein that does not compress
Incomplete apposition of the walls under transducer pressure is the primary direct criterion in accessible segments; Doppler findings and morphology add context.
Pitfall: Compress gently over a fresh free-floating clot — the diagnosis does not need force.

Supportive signs & checks

1.Absent phasicity or augmentation at the CFV
Loss of respiratory phasicity or of augmentation on calf squeeze at the common femoral vein points to iliac obstruction above the probe.
2.Age and postthrombotic features
Acute thrombosis typically distends the vein with soft, relatively hypoechoic material. Echogenic rigid material, a contracted vein, thick walls, synechiae, and recanalized channels favor chronic postthrombotic change. If features overlap, report the finding as indeterminate rather than guessing its age.
3.The femoral vein is a deep vein
Never let the obsolete 'superficial femoral' name reach a report — clinicians have withheld anticoagulation over it.
Pitfall: Report it as 'femoral vein' and, if thrombosed, explicitly as a deep vein DVT.
4.Duplicated systems
The femoral and popliteal veins are duplicated in a substantial minority — a patent twin channel can hide a thrombosed one.
5.Look for the alternative explanation
A Baker's cyst, hematoma, or muscle tear explains the swollen leg without DVT — find it and say it.

Wet-read snippets

Fill the blanks, then copy into your preliminary report.

Positive

Acute DVT: non-compressible ___ vein from ___ to ___, ___ (occlusive / non-occlusive). Most proximal extent: ___.

Negative

Comprehensive duplex from thigh through ankle demonstrates fully compressible deep veins with no acute venous thrombosis. Normal selected-site Doppler waveforms. Incidental: ___ (Baker's cyst / none).

Sources

SRU multidisciplinary consensus on US for lower-extremity DVT — Needleman L et al. Circulation (2018)
Antithrombotic therapy for VTE disease: second update of the CHEST guideline — Stevens SM et al. Chest (2021)

Content review: Content pending clinical review · 2026-07-15

Educational reference for trained clinicians. Verify every result against the cited original guideline before use. Not a substitute for clinical judgment or medical advice.