THE VEINS IN YOUR LEGS
An understanding of varicose veins and venous insufficiency begins with understanding the unusual arrangement of the veins in your legs. You really have two venous systems. You can see the superficial veins under your skin. When these become dilated and tortuous, they are called varicose veins. The word "varicose" comes from the Latin for dilated. The longest and largest of these veins is connected to the femoral vein and courses down the inner aspect of your thigh and leg. It is called THE GREATER (longer) SAPHENOUS VEIN. Another large superficial vein begins behind the knee and runs down the back of the calf of your leg. It is THE LESSER (shorter) SAPHENOUS VEIN. Both have branches that extend under the skin.

The second venous system in your legs, comprising the deep veins, begins with the femoral vein and runs deep inside the leg muscles. The deep veins carry the greatest portion of blood from your legs to be returned to your heart. That is no small amount, as the leg veins may hold as much as 70 percent of your total blood volume, depending on your posture.

The superficial veins are connected to the deep veins by short veins called PERFORATING VEINS. It is important to realize that the superficial veins drain through these perforating veins directly into the deep veins. As blood flows faster and faster through the deep veins to return to your heart, the flow literally sucks blood out of the superficial veins and empties them. If the deep veins are obstructed, that will affect the superficial veins as well. But you can have abnormalities of the superficial veins and have normal deep veins. This is often the case when one has uncomplicated varicose veins, without symptoms.

Another unique feature of the veins in your legs is that they have valves. These are just two flaps that open and allow the blood to flow toward your heart. They float open with the blood flow. They flap together to prevent the blood from flowing backward toward your toes. There are two distinct features of varicose veins. First, they are swollen and dilated, and second, the valves inside them do not work. The veins are thin-walled, but they do contain a muscular layer and elastic fibers. When the elastic and muscular layer are overstretched, the vein is a lot like a balloon that has been blown up too often - a dilated sac. Because of the vein's dilation, the flap-like valves do not quite meet. They cannot prevent blood from flowing backward toward your toes. As a result, when you are standing, the blood tends to run downhill and accumulates in the vessels in your lower legs, causing discoloration and swelling.

There are also valves in the perforating veins to prevent blood from flowing backward out of the deep veins into the superficial veins. When a perforating vein is dilated, its valves are incompetent, too. The point where it connects to the superficial veins may be especially large and rounded under the skin. These points are sometimes called "blow-outs."

GRAVITY
Since man is about the only one of earth's creatures to rely exclusively on walking upright for mobility, humans are the only creatures to have varicose veins. Varicosities have not been reported in four-legged animals. Man's upright posture in the field of gravity is what makes the difference. If we lived in a gravity-free environment, there would be fewer people with varicose veins and venous disease would cause far fewer problems.

One of the worst things you can do for varicose veins - and an important factor in causing them - is to stand or sit still. You can appreciate the problem by thinking of the city water tower. The taller the tower, the greater the water pressure. A column of blood follows the same principles of physics. The veins and arteries in your body are columns of blood. When you stand up, the columns of blood are at their tallest height. Without considering any factor other than gravity, the pressure in the ankle inside the veins of a 5 foot 10 inch individual while standing will be 80 to 100 mm Hg. That is how much pressure a column of blood from the foot to the top of the heart in such an individual would cause. When you are lying down, gravity does not increase the pressure in the ankle. It is like laying a water tower on its side and losing the gravity-pressure effect. The pressure inside the veins at the ankle is only about 10. When sitting the pressure in the ankle is not as high as when standing, but still much higher than when lying flat.

Why does the change in pressure make so much difference? The increased pressure helps to distend the veins. You can see this effect by doing an experiment with your hand. First be sure there is no constriction around your arm or wrist, such as a watch band. Now, while sitting upright, let your hand hang down at your side. See the veins in the back of your hand pop out. They are distended because of the column of blood from your shoulder to the back of your hand. Now raise your hand and hold the back of your hand level with your eyes. Watch the veins collapse. The pressure caused by gravity has been eliminated. The veins are no longer distended. Standing still creates a significant increase in pressure in the weak-walled veins and, in time, this can result in the overstretched state of varicose veins.

The increased pressure inside the veins while standing decreases the normal return of fluid from the tissues into the circulation. That is how standing causes swelling of the feet and ankles in the presence of varicose veins, and to some extent in people without varicose veins. The tissues literally fill up with fluid while you are standing and then empty into the veins when you are lying down. That is why swelling in the feet and ankles tends to disappear after a night's sleep.

When you are sitting, the column of blood is not so tall and the pressure in the veins in the ankles is less. But sitting may also involve compression of the backs of the thighs. This can obstruct the veins in the leg and impede normal forward flow toward the heart. Prolonged sitting can make swelling in the ankles worse. It is worth mentioning that prolonged pressure on the back of the thighs may also cause clots (thrombosis) in the deep veins, which is dangerous and may contribute to chronic venous insufficiency. That is one reason why you should get up and walk around every so often if you must sit, as during a long trip. A clot in the deep veins may also dislodge and go to the lungs, which is a life-threatening situation.

The heart is the point of reference in your circulation for the pressure effects from gravity. At all points below the heart, the pressure is increased because of gravity. The greater the distance below the heart, the greater the pressure will be. The pressure will be decreased at all points above the heart, and the greater the distance above, the lower the pressure. when you are sitting upright, the veins in the neck will normally collapse because there is no effective pressure to keep them full. But when you lie down, you can see the neck veins become distended with blood. It is like the experiment with the veins on the back of your hand.

CAUSE AND SYMPTOMS
Because varicose veins alone do not interfere that much with the venous circulation, they may not cause any symptoms at all. When they do, the symptoms usually start with mild aching, a feeling of heaviness or cramps. It is well to remember that varicose veins can be stripped out entirely and that does not interfere with venous circulation of the legs, so it is not surprising that they don't always cause symptoms.

Why do some people have varicose veins and others do not? Most people are exposed to the same degree of pressure in the veins of their legs. You could ask the same question about hernias. Some people seem to have veins that have weak walls. There definitely is a familial tendency to developing varicose veins. If a young woman's mother and her relatives have varicose veins, she is more likely to develop them, too. Such a family history is a good reason to take extra precautions to prevent venous distention.

One reason women are more prone to varicose veins than men is because of pregnancy. In some women, the veins become inflamed during pregnancy. But the mechanical factors are the most common problem. As the pregnant uterus enlarges, it presses directly against the main veins that drain the legs. This obstruction increases pressure in the entire venous system in the legs. Incidentally, an enlargement inside the abdomen, such as a tumor, may have a similar effect. Obesity is more common than a tumor, and when a person is overweight there is as much fat accumulated inside the abdomen as there is under the skin. That intra-abdominal pressure can affect the veins to some extent.

Prolonged standing is a factor. Individuals with occupations that require standing are more likely to develop varicose veins. But don't overlook the effects of pressure or constriction of the legs that prevents normal venous blood flow, such as girdles and tight underwear. A tight garter may induce swelling because of increased pressure inside the veins. As a rule, it is wise to avoid any garment that constricts the thigh or leg in any way.

Varicose veins may be secondary to chronic venous insufficiency - inadequate drainage of the deep veins. When the deep veins do not function properly, it is impossible for the superficial veins that drain into them to empty properly, and they tend to accumulate blood. The end result is dilation of the varicose veins.

VENOUS INSUFFICIENCY
Chronic venous insufficiency means an inability to pump venous blood back toward the heart, and it usually means major defects in the deep veins. Those defects are commonly a complication of thrombophlebitis, when a clot forms in the deep veins. A clot may cause immediate swelling of the leg because the major mechanism to transport blood out of the leg is blocked. There is an immediate swelling of the leg because the major mechanism to transport blood out of the leg is blocked. There is an immediate rerouting of blood through the superficial channels. As the clot is at least partially resolved, more normal blood flow is restored and the swelling subsides. But the damage may have been done, and where there was a clot, the valves in the deep veins may have been destroyed. When this happens, the blood accumulates in the deep veins and exerts increasing pressure at each lower level toward the ankle, the pressure being the highest at the level of the foot, because of the influence of gravity. This would go unnoticed if the valves in the perforator veins that connect the deep veins to the superficial veins remained competent, but they do not. They are either damaged from the original thrombophlebitis or the constant exposure of the perforator veins and the high pressure in the deep veins cause them to become incompetent. That affects the superficial veins, and it also allows venous blood to accumulate under high pressure in the outer tissues of the leg. The location of the incompetent perforator veins will determine the area of the leg or ankle that is affected. Commonly, this is the area at the level of the ankle bone to about half way up the leg.

The high pressure inside the veins causes fibrinogen, a blood protein that is essential to forming clots, to leak out into the tissues. It forms fibrin in the tissues. The enzymes that normally destroy fibrin inside the blood vessels do not exist outside in the tissues. The accumulated fibrin interferes with the circulation's ability to deliver oxygen and nutrients to the tissues. The fibrin accumulation and disturbance in circulation leads to formation of thick, hard tissue and the skin may be brownish. Since the tissues do not receive adequate circulation, they die, and an ulcer is formed - commonly called a varicose ulcer. Varicose veins - possibly as a complication of the deep vein and perforator vein insufficiency - are usually associated with the ulcer, but uncomplicated varicose veins, without deep vein disorders, seldom cause a varicose ulcer. In other words, the deep vein incompetence causes both the varicose ulcer and the varicose veins.

When a person is upright, the pressure in the deep venous system is very high because of gravity. With chronic venous insufficiency, this increased pressure is transmitted to the superficial veins and this results in swelling (edema) of the feet and ankles. When a person lies down, the pressure in the deep veins drops and the increased pressure in the superficial veins drops as well, allowing the fluid to be absorbed by the circulation and abolishing the swelling. In time, the swelling, fibrin accumulation and poor circulation lead to more persistent, doughy swelling of the involved areas with brownish discoloration over the skin, and sometimes a bluish cast from accumulated stagnant venous blood.

EXERCISE
Exercise is not harmful to varicose veins. Exercise of your legs increases the return of blood from your lower extremities to your heart. In the process, the pressure inside normal veins in the lower extremities actually falls. Although the pressure inside the veins at the level of the ankle while standing still may be equivalent to about 100 mm Hg, just taking one step causes the pressure to fall below 30. Merely shifting your weight may reduce the venous pressure to 20 or 30. The contraction of the muscles around the deep veins compresses them and squeezes blood up toward your heart. The blood doesn't flow backward because of the valves inside the veins. Contracting the calf muscles creates an external pressure around the deep veins in excess of 200. That is enough to compress the veins and squeeze the blood upward.

If the valves in the deep veins are incompetent, even through the blood is propelled upward during the contraction, the blood flows backward as soon as relaxation begins. As a result, the high pressure induced by gravity in the upright position is almost continuous and little is gained by exercise. But neither are matters made worse.

When the deep veins are competent, and the problem is simply varicose veins, exercise actually helps. Walking increases the speed of blood flow through the deep veins toward the heart. That helps to suck blood out of the superficial veins and into the deep veins. As the superficial veins empty, the pressure in them decreases. That is why it is not harmful, but actually helpful - for people who have uncomplicated varicose veins to exercise. Walking, jogging, running and cycling can all be helpful. Such exercise is much more healthy than standing. Standing and sitting are the things to avoid. Swimming is a particularly good exercise for people with chronic venous insufficiency. You eliminate the effects of gravity in causing high pressure in the veins and the exercise helps to promote circulation and remove excess fluid accumulation in the tissues.

If you have varicose veins or chronic venous insufficiency, it will help to wear medical graduated compression stockings that exert external pressure to the superficial veins. That helps to keep them from being stressed by the high pressure inside the deep vein. Such measures are important whether you are at rest or exercising.

ASSESSMENT
It is easy to see that you have varicose veins, but it is not so simple to determine if you have chronic venous insufficiency and to know the state of your underlying deep venous system. This is important in terms of management and treatment. Varicose veins should not be removed if the deep veins are blocked. Today, it is much easier to identify what part of the venous system is incompetent and to what degree.

PREVENTION AND TREATMENT
It is impossible to prevent an inherited tendency toward having varicose veins, but it is certainly possible to take measures that will help. Remember that varicose veins are veins that have been stretched so often that they become chronically dilated. The trick is to limit the opportunity to distend the veins. That means medical compression stockings in individuals with a strong family history of varicose veins. It means avoiding occupations that require prolonged standing, and it means being careful about how you sit. Always try to sit in a chair that is low enough or with the seat tilted in such a manner that there is little or no pressure on the back of the thighs. do not sit for prolonged periods of time. Do get up and walk around to speed up circulation through your veins. And it is important for women who are pregnant to wear compression stockings at least during the last trimester of pregnancy.

The use of pressure garments is helpful. Medical graduated compression stockings are designed to provide the greatest pressure at the level of the ankle and diminishing pressure as the stocking goes up over the thigh. This design is important to prevent tourniquet-like compression to the leg. You should know that many stockings that provide mild pressure are not adequate to prevent tissue swelling and the complication of varicose veins and venous insufficiency.

In many instances the chief indication for treatment of varicose veins is cosmetic. This is most often true of the smallest varicose veins called "spider veins." These very small veins that become dilated do not mean that the larger veins that form the major superficial venous system will necessarily become or already are varicose veins. There is an inherited tendency to have spider veins. The condition is aggravated by prolonged standing, injury or pregnancy. Spider veins often cause a mild burning sensation, although they may be asymptomatic. Today, these are treated successfully by injecting the vein, or cluster of spider veins, with a sclerosing solution. This irritates the tiny vessels to scar and disappear. The procedure is like having a mosquito bite.

Laser treatment is sometimes used on spider veins. Its objective is to heat the blood in the vein, "cooking" or coagulating it to obliterate the vessel. It is effective on the tiniest of vessels but is not appropriate for varicose veins since it can create severe scarring of the skin along the path of the vein. Endovenous laser ablation is used for these large varicose veins.

When the venous problem is limited to varicose veins (the superficial venous system) they can also be treated by sclerotherapy. A sclerosing agent (usually sodium tetradecyl sulfate) is injected directly into the varicose veins and it irritates and collapses the lining of the vein. The inner surface of the collapsed vein grows together and obliterates the vein. To use the technique successfully, the vein must be collapsed and then compressed with medical compression stockings. If this is not done, clotted blood may be trapped within the vein and hold it open. Trapped blood is later absorbed, leaving the varicose vein still present. After a treatment, the patient can resume walking immediately. Medical compression stockings are worn constantly for a few days, then only during waking hours for the remainder of the compression period.

The other commonly used method of removing varicose veins is to strip them out surgically. This procedure involves passing a stripper - a flexible rod-like device - through an incision in the vein at the ankle all the way to the groin for the greater saphenous vein. The stripper is sutured to the saphenous vein in the groin. All the branches of the vein are excised or stripped as well. The perforator veins are identified and tied off through small incisions. When all the branches and perforating veins have been removed or tied, the long vein is literally pulled out from the top to the ankle. The leg is bandaged and walking around is allowed the first postoperative day. The bandages may be removed the next day and the patient must then use medical gradient pressure stockings for 10 to 14 days.

There is considerable disagreement about whether sclerotherapy or stripping should be used. Sclerotherapy has the advantage of being an office procedure and does not require hospitalization. It does not leave surgical scars and is less expensive and less painful. Recurrences of varicose veins do occur with both procedures, and some doctors believe recurrence occurs earlier after sclerotherapy than after stripping. Recurrences are normally retreated as before, a simpler procedure for sclerotherapy than surgery. Patients with recurrences who are allowed to choose how to have the recurrences treated nearly always choose sclerotherapy over surgery. Studies show that patients who choose sclerotherapy over surgery cite these as the most important advantages: they want to minimize pain and scarring, want to avoid anesthesia, don’t like the idea of being cut open, don’t want the risk of wound infections, want the ability to continue to work and exercise, and want to avoid hospitalization.