Diagnosing spider veins is easy! Sadly, anyone can see them. However, it's important to know that they are purely a cosmetic condition and are unrelated to any serious underlying venous disease.
They are simply dilated superficial veins and do not indicate any damage to the deeper veins that carry blood to the heart.
Therefore, an ultrasound of the veins of the legs is not necessary when seeking treatment for spider veins.
This kind of ultrasound should only be done if there are other signs of chronic venous insufficiency such as varicose veins, leg swelling and skin color changes.
A varicose vein which indicates a medical problem is very different from a spider vein. It’s a large bulging vein that raises the surface of the skin. Patients with varicose do need ultrasounds.
If your doctor recommends an ultrasound based only on your spider veins please get a second opinion.
It would be an unnecessary test if there is no sign of deeper underlying disease like varicose veins. Be especially careful if you are offered treatment for your deep veins like ablation or surgery if your only problem is spider veins. Instead, run to a fellowship trained vascular surgeon who will give you what you need with no unnecessary procedures.