What is chronic venous insufficiency?
Chronic venous insufficiency is a debilitating leg problem in which blood does not flow normally up through the veins in the legs toward the heart. In normal veins a series of specialized, one-way valves work together, opening to allow blood to flow upward, then closing to keep the blood from flowing back toward the feet. Venous insufficiency occurs when valves are damaged or not functioning properly. As the valves deteriorate, blood leaks or flows backward and pressure in the vein increases, stretching and dilating the vessel. Blood stagnates (pools) in the veins of the lower legs, increasing the blood pressure in the legs, and causing chronic inflammation in the veins.
People with long-term, untreated venous insufficiency sometimes develop open sores in the skin called venous ulcers. Ulcerations develop in areas where blood collects and pools, as swelling there interferes with the movement of oxygen and nutrients through tissues. Over time a visible ulcer develops on the skin. Venous ulcers usually appear just above the ankle on the inside of the leg. If they are not treated they can become quickly infected or even gangrenous.
What are the risk factors and symptoms for chronic venous insufficiency and venous ulcers?
The incidence of venous insufficiency rises with age, and is also linked to a family history of varicose veins, a sedentary lifestyle, or to jobs that require people to spend many hours on their feet. Venous insufficiency can also be caused by a partial blockage of the veins, for example by a blood clot (a condition called deep vein thrombosis or DVT).
The most common early symptom of venous insufficiency is chronically swollen ankles; the feet and calves may also swell. The swelling can be accompanied by a dull aching, cramping, or feeling of heaviness in the legs and feet that becomes worse after prolonged standing.
As the condition progresses, people with venous insufficiency develop brown patches and deteriorating (flaking or hardening) skin around the ankles. If venous insufficiency is not treated, venous ulcers may develop on the lower legs.
What diagnostic tests may be needed for venous insufficiency or venous ulcers?
In addition to a complete medical history and physical examination, diagnostic procedures for chronic venous insufficiency may include any, or a combination, of the following:
Duplex ultrasound. This is a type of vascular ultrasound procedure done to assess blood flow and the structure of the leg veins. The term "duplex" refers to the fact that two modes of ultrasound are used - Doppler and B-mode. The B-mode transducer (like a microphone) obtains an image of the vessel being studied. The Doppler probe within the transducer evaluates the velocity and direction of blood flow in the vessel.
Magnetic resonance venography (MRV). This is a diagnostic procedure that uses a combination of a large magnet, radiofrequencies, and a computer to produce detailed images of organs and structures within the body. An MRV uses magnetic resonance technology and intravenous (IV) contrast dye to visualize the veins. Contrast dye causes the blood vessels to appear opaque on the x-ray image, allowing the physician to visualize the blood vessels being evaluated. MRV is useful in some cases because it can help detect causes of leg pain other than vein problems.
What are the treatments for chronic venous insufficiency and venous ulcers?
Chronic venous insufficiency
There are several minimally invasive treatments for venous insufficiency, which are aimed at reducing swelling and improving the return of blood to the heart.
Elevating the legs (above the heart) when not standing helps the blood return to the heart, decreases blood pooling, and ultimately decreases swelling.
Exercise, which stimulates the calf muscles and increases circulation, may also be recommended.
Doctors treat venous ulcers by working to prevent infection and promote healing of the wound. Many novel treatments, outlined below, are now available to help heal venous ulcers.
Topical creams. Doctors sometimes advise patients to use a topical cream containing hydrocortisone to minimize itching, provided it is not applied to open skin. Anti-fungal creams can also prevent infection from developing on the skin of the feet and toes. However, people with venous insufficiency are advised not to use antibiotic creams because they worsen inflammation.
Compression stockings. The most common treatment for venous insufficiency is compression stockings. These special stockings apply constant, even pressure to the leg. This increases circulation and prevents blood from flowing backward, thereby reducing much of the swelling caused by the disorder. In addition, compression stockings can help prevent venous ulcers from forming or can help accelerate the healing of an existing ulcer. Compression stockings have to be worn daily to be effective. Doctors may also prescribe medication to thin the blood, particularly in patients with a high risk of blood clots.
Unna boots. An Unna boot is a moist gauze bandage that is applied around the lower leg, from the region of the ulcer to just below the knee. The gauze hardens to form a snug boot on the leg. The support from the boot helps improve blood flow in the veins and heal the ulcer. The boot stays on for 48 hours to two weeks and then is replaced if the wound has not healed.
Transparent dressings. A transparent dressing is a clear, plastic-like film that is applied over the wound. The dressing is changed every 5 to 7 days. A support stocking is worn over the dressing to help hold it in place and improve circulation in the leg and foot.
Hydrocolloid dressings. A hydrocolloid dressing is a specialized bandage with a breathable outer layer that keeps liquid, bacteria, and viruses out, and an inner layer that absorbs drainage from the wound to promote healing. The dressing also helps to remove any non-living tissue from the wound (a process called debridement). The dressing is changed every 1 to 7 days.
Growth factors. Growth factors are investigational medications that doctors apply to the wound in the hope of promoting the growth of new tissue.
Occasionally, your physician may recommend either surgical therapy or catheter-based interventional treatment for your chronic venous insufficiency or venous ulcers. Doctors may sometimes perform surgery to remove any non-living tissue from a wound to promote its healing. This surgical procedure is called debridement. Other interventional treatment may include vein ablation.
Debridement. During debridement vascular specialists surgically remove all non-viable, infected tissue and bone from a non-healing ulcer. This process activates blood component called platelets and growth factors, which both promote healing. Doctors often perform debridement if a patient with a venous ulcer shows signs of infection including fever, elevated white blood count, and persistent or increased drainage.
Laser treatment. Laser treatment may be indicated for chronic venous insufficiency in which certain veins in the leg are needed to closed permanently to reduce the pressure around the venous ulcers. Until recently, laser treatment was mainly used for treatment of spider veins on the face. However, newer laser technology can now effectively treat abnormal veins in the leg as well. There are several types of lasers that may be used to treat varicose veins. The physician inserts a tiny fiber into a varicose vein through a catheter. The fiber sends out laser energy that destroys the diseased portion of your varicose vein. The vein closes and your body eventually absorbs it.
Closure ablation. Ablation involves the insertion of a thin, flexible tube called a catheter inserted into abnormal veins in the leg. The tip of the catheter heats the walls of the vein using radio frequency energy (also known as closure procedure) and destroys the vein tissue. Once destroyed, the vein is no longer able to carry blood and is absorbed by your body.