Nonthrombotic Iliac Vein Lesions

Causes

The most common cause of NIVL is extrinsic compression of the iliac vein, most frequently by the right common iliac artery. Other causes can include:

• May-Thurner syndrome: This is a condition where the left common iliac vein is compressed by the right common iliac artery and the overlying ligament. It is more common in women (Click here to read more on May Thurner Syndrome)
• Endometriosis
• Pelvic tumors
• Fibrosis (scar tissue)
• Prior surgery

Symptoms

Many people with NIVL do not have any symptoms. However, when symptoms do occur, they can include:

• Leg swelling, especially in the evening or after standing for long periods
• Pain in the leg, which may worsen with activity and improve with elevation
• Discoloration of the skin
• Varicose veins
• Pelvic pain (more common in women)
• Leg ulcers (in severe cases)

Diagnosis

NIVL can be diagnosed using a variety of tests, including:

• Venous duplex ultrasound: This is a non-invasive test that uses sound waves to create images of the veins and measure blood flow.
• CT scan or MRI scan: These imaging tests can provide a more detailed view of the iliac veins and surrounding structures.
• Venography: This is an X-ray of the veins that is performed after injecting a contrast dye into the bloodstream.

Treatment

Treatment for NIVL depends on the severity of the condition and the patient’s symptoms. If there are no symptoms, no treatment may be necessary. For symptomatic patients, treatment options may include:

• Compression stockings: These garments help to improve blood flow in the legs and reduce swelling.
• Medication: Blood thinners (anticoagulants) can help to prevent blood clots from forming.
• Angioplasty and stenting: In this procedure, a balloon is used to open up the narrowed vein, and a stent may be placed to keep it open (Click here to read more on Angioplasty/ stenting)
• Bypass surgery: In severe cases, surgery may be necessary to create a new pathway for blood to flow around the blockage.