What is the initial test to order for a patient presenting with varicose veins?

Initial Diagnostic Test for Varicose Veins

Duplex ultrasound of the lower extremity is the recommended initial test for patients presenting with varicose veins. 1

Rationale for Duplex Ultrasound as First-Line Test

• Duplex ultrasound is widely recognized as the gold standard first assessment for evaluating the lower extremity venous system in patients with varicose veins 1
• It provides comprehensive evaluation of both the deep and superficial venous systems, including:
  • Great saphenous vein (GSV) and small saphenous vein (SSV) assessment 1
  • Accessory saphenous veins evaluation 1
  • Identification of perforating veins 1
  • Assessment of alternative refluxing superficial venous pathways 1

Key Components of Duplex Ultrasound Evaluation

• Examination should include both transverse and longitudinal planes of venous structures 1
• Assessment for venous reflux (retrograde flow >500 ms), which is the primary pathophysiologic mechanism in varicose veins 1
• Evaluation of respiratory variation and cardiac pulsations to confirm patent pathway to the heart 1
• Mapping of vein anatomy similar to contrast venography but with added hemodynamic information 2
• Assessment of vein valve function and perforator vein reflux 2

Advantages Over Other Imaging Modalities

• Non-invasive procedure with no radiation exposure 1, 2
• Provides both anatomic and hemodynamic information in a single test 2
• Allows direct preoperative marking of the skin for surgical planning 3
• Superior to venography for detecting variant varicosis in most cases 3
• Excellent agreement with venography in grading saphenous vein reflux 3

Clinical Implications

• Accurate duplex ultrasound assessment helps guide appropriate treatment selection 4
• Identifies underlying venous reflux even in the absence of visible bulging veins (so-called "hidden varicose veins") 4
• Should be performed in the erect position by a specialist trained in ultrasonography 4
• Essential for detecting arteriovenous anastomoses that may contribute to varicose vein etiology 5

Special Considerations

• For patients with extensive unexplained leg swelling, iliac veins should also be imaged to exclude isolated iliac DVT if proximal ultrasound is negative 1
• In cases where ultrasound is impractical (e.g., excessive subcutaneous tissue, leg casting) or nondiagnostic, alternative imaging such as CT venography or MR venography may be considered 1
• For suspected pelvic-origin varicose veins in females, additional imaging of the IVC and iliac veins may be appropriate 1

Duplex ultrasound provides the most comprehensive initial assessment of varicose veins, offering both anatomical and functional information that is crucial for treatment planning and clinical decision-making.