Veins of the Legs – Normal and Abnormal

Our legs receive blood from the heart to nourish the skin and tissues with oxygen and nutrients. Arteries deliver this blood which is pushed through the body from the contraction of the heart muscle. Once the blood arrives in the leg and foot it must begin a journey returning to the heart which is the function of our veins. This blood flow in the veins occurs against gravity, moving up the legs back to the heart.

How is this accomplished? When you consider it, there is no pump in the foot to propel blood up the leg against gravity. Blood is propelled out of the leg by the contraction of the muscles of the calf squeezing the veins and pushing the blood back toward the heart. The blood is directed up towards the heart through a series of one-way valves. The valves prevent the blood from flowing back down the leg by opening in the direction of the heart and closing when blood tries to move towards the feet with gravity.

Normal Vein Valves

In the healthy leg, vein valves protect the leg veins from becoming distended from a build up of pressure. Varicose veins occur when these vein valves become aged or damaged, allowing blood to flow towards the feet resulting in a build up of pressure in the veins resulting in vein enlargement. This is referred to as venous reflux.

Abnormal Valve

Venous reflux causes abnormal veins and their branches become progressively dilated. When we evaluate patients with varicose veins we determine where the broken vein valves are located and formulate a plan for correcting the problem based on a clear understanding of the venous ultrasound map.

Varicose Vein Patterns

Different patterns of vein problems exist. Each pattern tells the doctor where the most likely site of venous reflux exists. Treating varicose vein problems early prevents worsening of the patterns of venous disease.

Varicose Vein Patterns

Venous Reflux

The most common cause of varicose veins is reflux in the Greater and Lesser Saphenous Veins. Valves that have failed transmit pressure down the vein causing enlargement of the vein branches along the course of the GSV. The typical location of vein clusters in GSV and LSV reflux are shown below.

Greater Saphenous Vein Reflux

The photograph shows the pathway of the GSV as marked on the skin. Varicose veins on the calf are branches varicosities of the main vein.

Reflux occurs when vein valves are broken which allows blood to move down the vein towards the foot under the force of gravity. Usually it is the vein valve at the top of the leg which becomes incompetent first. Blood moves down the vein under pressure to the next valve which eventually fails. Each subsequent valve fails as more pressure is forced upon it from above. This causes veins to dilate and become varicose veins.

Normal Valve Function

Normal Valve Function

An example of normal veins and vein valves is presented above. All the valves are closed and will only allow blood to flow up towards the heart. When valve failure occurs so that pressure is allowed to enter the superficial veins, other vein segments and vein valves will become dilated and permit vein blood flow to move away from the heart and down towards the feet as illustrated below.

Abnormal Valves

Veins that become dilated can be seen in many sizes, shapes and colors. Large caliber varicose veins, small veins or venules as well as spider veins or telangiectasia can occur as a result of pressure buildup in the venous system. Examples of large veins and spider veins are seen below.

Large Varicose Veins (Reflux)

Spider Veins

Vein Treatments

The recommendations we make for the treatment of veins depends upon the type, location, and the results of venous duplex testing. There are three basic treatment scenarios: venous reflex, large caliber varicose veins, and spider veins. Most patients have a combination of these vein disorders.