Recommended Imaging for Varicose Veins Evaluation
Duplex ultrasound of the lower extremity is the definitive initial imaging test for evaluating varicose veins and should be performed in all patients before any treatment is considered. 1, 2
Why Duplex Ultrasound is the Gold Standard
Duplex ultrasound is widely agreed upon as the first and best assessment of the lower extremity venous system for varicose veins. 1 This recommendation comes from the most recent 2023 American College of Radiology Appropriateness Criteria, which represents the highest quality guideline evidence available. 1
What the Examination Must Include
The duplex ultrasound evaluation should comprehensively assess: 1
- Condition of the deep venous system to rule out thrombosis or reflux 1
- Great saphenous vein (GSV) and small saphenous vein (SSV) for incompetence and reflux 1
- Accessory saphenous veins for reflux pathways 1
- Perforating veins - presence, location, and clinical relevance of incompetent perforators 1
- Alternative refluxing superficial venous pathways 1
- Evaluation in both transverse and longitudinal planes for complete anatomic assessment 1
Technical Requirements for Optimal Results
The examination should be performed with the patient in the erect (standing) position to properly assess venous reflux under physiologic conditions. 3 The study should ideally be performed by a specialist trained in venous ultrasonography. 3
Reflux is defined by specific time thresholds: 2
- >350 milliseconds in perforating veins 2
- >500 milliseconds in superficial and deep calf veins 2
- >1,000 milliseconds in femoropopliteal veins 2
When Alternative Imaging May Be Considered
CT Venography (CTV)
CTV is not a first-line examination but may be used adjunctively in rare cases where ultrasound is limited, such as in patients with severe obesity where characterization of lower extremity veins is suboptimal. 1 Given the high recurrence rate of 15-35% at 2 years post-intervention, detailed anatomic characterization before therapy can help ensure appropriate treatment selection. 1
MR Venography (MRV)
MRV is similarly not first-line but can be used adjunctively in rare cases where ultrasound imaging is limited, characterization is suboptimal, or when avoiding iodinated contrast is necessary. 1
Catheter Venography
There is no relevant literature supporting catheter-directed venography of the lower extremity or iliac veins as routine evaluation for varicose veins. 1 While catheter venography can evaluate descending venography for deep vein reflux, it is not recommended for standard bilateral GSV insufficiency with visible varicose veins. 1
Critical Pitfalls to Avoid
Do not proceed with any varicose vein treatment without duplex ultrasound confirmation, even for small cosmetic varicosities, as most have underlying venous reflux from saphenous, perforator, or local feeding veins that must be identified. 3
Ultrasound must be performed within 6 months of any planned intervention to ensure accurate anatomic and hemodynamic assessment for treatment planning. 4
The examination is operator-dependent, so results can be limited by inadequate technical expertise, bandages, casts, or patient pain. 2 Ensure the study is performed by experienced personnel.