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Growths and Malformations of the Vessels

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Growths and malformations of the vessels (angiomas) are collections of abnormally dense blood or lymph vessels, usually located in and below the skin, that cause red or purple discolorations.

Growths and malformations of the vessels often appear at birth or soon afterward, and some may be referred to as birthmarks. Examples include hemangiomas, port-wine stains, lymphangiomas, pyogenic granulomas, and spider angiomas. These different growths and malformations are usually recognized by their appearances, thus biopsies are rarely necessary. About one third of all newborns have some type of growth or malformation of the vessels, many of which disappear by themselves.

Hemangiomas

Hemangiomas are abnormal overgrowths of blood vessels that can appear as red or purple lumps in the skin and on other parts of the body.

Hemangiomas develop soon after birth and tend to enlarge rapidly during the first 6 to 18 months of life. After this, they begin to shrink. About three quarters of hemangiomas disappear by age 7, although the skin that remains is often slightly discolored or scarred.

Superficial hemangiomas (strawberry hemangiomas, cherry angiomas), the most common type of blood vessel growth, occur on or near the surface of the skin. They appear as raised, red, irregular growths or patches that range from tiny bumps to large, deforming swellings 3 or 4 inches across. They usually occur on the torso and can number from a few to dozens. Superficial hemangiomas are harmless; if they are bothersome, a doctor can remove them with an electric needle or laser.

Deep hemangiomas (cavernous hemangiomas) grow within the skin and deep beneath it. They cause the skin to bulge and may be purple or, if they are very deep, flesh-colored. Most deep hemangiomas grow between ¼ inch and 2 inches across, although sometimes they grow much larger. More than half occur on the head and neck. Sometimes, hemangiomas develop in organs, such as the liver (see Tumors of the Liver: Hemangioma).

Superficial and deep hemangiomas do not cause pain but occasionally break open (ulcerate) and bleed, which can be difficult to stop. Hemangiomas around the eye may grow large enough to block vision, which can lead to permanent vision loss if uncorrected. Hemangiomas may also block the nose or throat, which can obstruct breathing.

Because hemangiomas often go away on their own, doctors do not treat them when they first appear unless they grow rapidly, obstruct vision or breathing, ulcerate, or are cosmetically distressing. Doctors usually treat any facial hemangiomas that have not gone away by age 5 or 6.

When treatment is required, doctors inject small superficial hemangiomas with corticosteroids or surgically remove them if the injections do not work. People with rapidly growing or large, ulcerating hemangiomas take corticosteroids by mouth. For older children in whom the hemangioma has shrunken, laser therapy or surgery may improve the appearance of the skin.

Using Lasers to Treat Skin Problems

A laser is a device that produces a thin, very intense beam of light that has one particular color (wavelength). Laser beams can be very powerful, containing thousands of watts of energy. But because this energy is in the form of light, it does not affect human tissue until it is absorbed. Whether tissue absorbs laser light depends on the color of the tissue and the color of the light. For example, red blood vessels absorb yellow, blue, and green light best, so lasers of these colors are used to selectively target blood vessels in the treatment of hemangiomas. Other colors are used to target different conditions. Laser beams may be continuous, like a flashlight, or briefly pulsed in individual flashes. The pulse duration helps determine the depth and amount of effect of the laser beam.

Laser treatments are sometimes combined with photodynamic therapy, in which certain light-absorbing chemicals are applied to skin tumors or given intravenously. When these chemicals are struck by laser light, they break apart into substances that help destroy the tumor.

Blood vessel growths, such as hemangiomas, and malformations, such as port-wine stains, are commonly treated with laser therapy. Laser therapy is also used to remove unwanted hair, tattoos, skin discoloration, scars from acne or sun damage, and cancerous tumors.

Port-wine Stains

Port-wine stains (capillary malformations, nevi flammeus) are flat pink, red, or purplish discolorations present at birth due to malformed blood vessels.

Port-wine stains are harmless, permanent discolorations. However, their cosmetic appearance may be psychologically bothersome or even devastating. The stains appear as smooth, flat pink, red, or purple patches of skin. Port-wine stains may be small or may cover large areas of the body. Stains that appear on the nape of the neck of newborns have been referred to as stork bites. Very rarely, port-wine stains appear in conjunction with Sturge-Weber syndrome, a rare hereditary disorder that leads to mental retardation and growth deformities.

Small port-wine stains can be covered with cosmetic cover-up cream. If a stain is bothersome, its appearance can be greatly improved with laser therapy (see Using Lasers to Treat Skin ProblemsSidebar).

Lymphangiomas

Lymphangiomas (lymphatic malformations) are skin bumps caused by a collection of enlarged lymph vessels—the channels that carry lymph (a clear fluid related to blood) throughout the body.

Lymphangiomas are uncommon, but usually appear between birth and age 2. They may be tiny bumps or large, deforming growths. Lymphangiomas do not itch or hurt and are not a form of cancer. Most lymphangiomas are yellowish tan, but a few are reddish. When injured or punctured, they release a colorless fluid. Although treatment is not usually needed, lymphangiomas can be removed surgically. However, such surgery requires the removal of many layers of skin and underlying tissue, because lymphangiomas grow deep beneath the surface.

Pyogenic Granulomas

Pyogenic granulomas are scarlet, brown, or blue-black slightly raised areas caused by increased growth of capillaries (the smallest blood vessels) and swelling of the surrounding tissue.

The condition develops rapidly, usually after injury to the skin. For unknown reasons, large pyogenic granulomas may develop during pregnancy, appearing even on the gums (pregnancy tumors). Pyogenic granulomas appear as ¼- to ½-inch growths that rise from the surface of the skin. They do not hurt, but they bleed easily when bumped or scratched because they consist almost entirely of capillaries.

Pyogenic granulomas sometimes disappear by themselves, but if they persist, a doctor usually removes them surgically, with laser therapy, or with an electric needle (electrocoagulation). A sample of tissue may be sent to a laboratory to ensure that the growth is not a type of melanoma or other skin cancer. Sometimes pyogenic granulomas recur after treatment.

Spider Angiomas

Spider angiomas are small, bright red spots consisting of a central dilated blood vessel surrounded by slender dilated capillaries that resemble spider legs.

Many people have a few spider angiomas, which are often referred to as "broken" blood vessels. Spider angiomas on the face are commonly seen in fair-skinned people and are thought to be due to sun exposure. In most people, there is no known cause, but people with cirrhosis often develop many spider angiomas, as do many women who are pregnant or who are using oral contraceptives. Spider angiomas are not present at birth.

Spider angiomas appear as tiny, hard-to-see red spots less than ¼ inch across. They are harmless and generally cause no symptoms; they are only of cosmetic significance. Spider angiomas that develop during pregnancy or oral contraceptive use usually disappear on their own 6 to 9 months after childbirth or after discontinuing oral contraceptive use. If treatment is desired for cosmetic reasons, a doctor can destroy the central blood vessel with laser therapy or with an electric needle.

Last full review/revision February 2003

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