1. What is a seroma?
A seroma is a pocket of lymph fluid within a cavity inside the body. This fluid, also called serum, is the portion of blood that remains after red and white blood cells have been removed. A seroma can occur after liposuction, but it is not a serious complication. A seroma will usually disappear gradually over several weeks or months without treatment. A surgeon may drain the seroma to resolve it more quickly. Seromas can be caused by the use of a large cannula during liposuction or an aggressive technique. Seromas commonly result from ultrasonic assisted liposuction. Seromas rarely occur when surgeons use the tumescent liposuction with microcannulas and leave incisions open for drainage.
2. What causes the seromas associated with liposuction?
Seromas occur during liposuction when the lymphatic vessels within the fatty tissue are traumatized during surgery. Lymphatic vessels are small tubular structures that drain tissues or fluids that leak out of capillary blood vessels. Lymphatic vessels can be ruptured by the use of large cannulas, which create large cavities in the fatty tissue and can remove lymphatic vessels altogether. When this happens, seromas can form after liposuction. Seromas are also common after ultrasonic assisted liposuction because ultrasonic cannulas create heat that injures blood vessels and lymphatic vessels. When lymphatic vessels are damaged or removed during liposuction, the fluid collects within the empty cavities where fat was removed. These cavities are fluid are seromas.
3. How can seromas be prevented?
Seromas can be prevented if the surgeon avoids surgical trauma to the lymphatic vessels and if he leaves incisions open to encourage draining of serum from the areas treated with liposuction.
The use of microcannulas can reduce the risk of seromas because they are small in diameter. Microcannulas make small tunnels within the fat deposits so there is less chance of a seroma forming. Large cannulas create larger cavities within the fat and are more likely to damage lymphatic vessels, thus causing seromas.
Another way seromas can be prevented is by leaving the incisions open for drainage. When the incisions are closed with stitches, fluid is trapped under the skin where it stagnates in the cavities in the fat. This can result in a seroma. If the incisions are left open to drain and compression garments are worn, the fluid left over from the tumescent liposuction is allowed to drain and the tunnels within the fat collapse. The collapsed cavities do not provide a place for fluid to collect so it drains out of the body. Therefore a seroma cannot form.