phlebography

Phlebography, also called venography, is a radiographic examination of the venous system performed after the administration of a radiopaque contrast agent. By outlining the veins on X-ray images, it provides detailed information about venous anatomy and patency.

Most phlebography is catheter-directed, with contrast injected into a peripheral vein (commonly in the leg or arm) and fluoroscopic imaging used to visualize the venous segments. In leg venography, techniques are described as ascending or descending, depending on the direction of contrast flow, and aim to visualize the superficial and deep venous systems from the foot to the pelvis.

Indications include evaluation for suspected venous thromboembolism when noninvasive tests are inconclusive, assessment of chronic venous insufficiency, preoperative mapping of venous anatomy for bypass or access procedures, and investigation of venous obstruction or vascular malformations.

Phlebography is invasive and uses ionizing radiation and iodinated contrast, carrying risks such as allergic reaction, contrast-induced nephropathy, venous injury, and procedure-related hematoma. With the advent of duplex ultrasonography, CT venography, and MR venography, phlebography is now largely reserved for selected cases or for interventional planning.

Historically, venography was a standard tool for venous imaging before noninvasive modalities became widespread. Today, it remains a useful technique in certain centers where detailed venous mapping is required or when other imaging modalities are inconclusive.