A 19 year old female with a past medical history of autism and anxiety presents with right lower extremity swelling and pain. Two weeks ago, she developed right lower back pain with radiation into her right hip and leg which she describes as sore. She is sexually active and was started on hormonal contraception 2-3 months ago. Vital signs include BP 117/75, HR 108, RR 18, SpO2 99% RA, T 97.5F. The patient’s right lower extremity is neurovascularly intact with tenderness to palpation and swelling without color change. A right lower extremity ultrasound is shown below. What’s the diagnosis? How is this ultrasound performed?
Answer: Right Common Femoral and Popliteal DVT
DVT Ultrasound Evaluation: must evaluate at least 2 regions, typically femoral and popliteal veins
Femoral Vein
- Most often performed using the linear probe (curvilinear probe may provide greater penetration for larger body habitus)
- Start just distal to the groin where the iliac vein becomes the common femoral vein
- Follow common femoral vein down to where the common femoral splits off into greater saphenous, femoral, and the deep femoral vein (approximately mid-thigh) and continue to follow the femoral vein until at least the mid-thigh, compressing in 1 cm increments to ensure compressibility of veins throughout
Popliteal Vein
- Place probe on posterior aspect of the knee and look for popliteal vein (superficial to popliteal artery)
- Follow popliteal vein and compress in 1 cm increments to ensure compressibility until the vein divides into the fibular, posterior tibial and anterior tibial veins
DVT Ultrasound Pearls:
- A vein is compressible if the walls touch with compression – if you are pushing hard enough to compress the artery but not the vein, there is likely a DVT!
- Evaluation of femoral and popliteal regions is crucial because a DVT within either of these veins is considered “proximal” and requires medical management with anticoagulants and further evaluation for iliac/IVC involvement or pulmonary embolism.
- Clinical diagnosis of DVT is typically unreliable due to the infrequency of classic findings (edema, warmth, erythema, pain, and tenderness) which are only present in 23 to 50 percent of patients
- Venogram remains the “gold standard” for the diagnosis of deep venous thrombosis. However, ultrasound is the most accurate non-invasive test to diagnose deep venous thrombosis.
This patient received prompt anticoagulation in the ED and after being admitted, received a CT venogram revealing acute deep vein thrombosis in the infrahepatic inferior vena cava, bilateral common iliac, bilateral external iliac, bilateral internal iliac and bilateral common femoral veins requiring percutaneous mechanical thrombectomy!
References:
Baker M, Anjum F, dela Cruz J. Deep Venous Thrombosis Ultrasound Evaluation. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-.
