Varicose veins greater than 3 mm over the thigh or calf are generally associated with:

The presence of varicose veins greater than 3 mm, especially over the thigh or calf, is commonly associated with accessory branches of the saphenous system. These accessory veins can contribute to the development of varicosities when they become incompetent, leading to increased venous pressure and subsequent varicose vein formation.

Accessory branches of the saphenous system often exist to help drain blood from the lower extremities and can become dilated and tortuous when the primary drainage pathways are compromised. This is particularly true in cases where the saphenous veins experience valvular incompetence. The development of varicose veins in this context indicates a disruption in normal venous return, where accessory branches may take on more workload to compensate.

Understanding this association is crucial for a phlebology sonographer, as it helps inform the diagnosis and potential treatment methods for managing venous insufficiency and its complications.