There have been several questions on our Lymphedema forum asking about the surgical treatment options for lymphedema so I decided to provide a general discussion of the surgical management of lymphedema. The are several different surgical approaches to the treatment of lymphedema. For the sake of simplicity, most of the techniques involve the formation of an anastamosis between the lymphatic system and the venous system. An anastamosis is essentially a bridge or conduit from the lymphatic system to the venous system. The goal of these microvascular surgeries is to form a channel between the pooled and blocked lymphatic system and the venous system so that the venous system can remove the accumulated lymphatic fluid.

   A brief review the physiology of the lymphatic system is in order to help understand these surgical techniques. Arterial, or oxygenated blood is pumped from the heart to the various tissues. The oxygen is removed from the blood by the cells and cellular waste products are dumped into the blood from the cells. The deoxygenated blood is the venous blood and it flows back to the heart where it is pumped to the lungs to pick up more oxygen.

   All cells are bathed by a small amount of fluid that circulates around the cells and then drains into the lymphatic system. The lymphatic system arises from these tiny spaces between cells. In many ways, the lymphatic and venous system are similar since they both function to remove excess waste from cells. The lymphatic system differs from the venous system because it is a much more delicate system of channels. In addition, the volume of lymphatic flow is less than 10% of the flow of the venous system. The lymphatic system is so delicate that in many places the walls of the lymphatic channels are only a few cell thick. These channels are often difficult to identify under the microscope and it takes a trained eye to identify them. The lymphatic channels converge into larger channels and finally drain into the venous system before entering the heart.

   These lymphatic and venous systems, while separate, run in parallel. Therefore, a bridge can be formed between the two systems allowing for the drainage of excess fluid from an obstructed lymphatic system. As you might imagine, such bridges would have to be very small. In addition, once formed, flow could go from the lymphatic system to the venous system, but flow could also go from the venous system to the lymphatic system. Since the lymphatic system is frequently obstructed in cases of lymphedema, the lymphatic system is more likely to be a higher pressure than the venous system and the flow is likely to go from the lymphatic system to the venous system thereby alleviating the condition of lymphedema.

   While the concept of forming a surgical channel to remove excess lymphatic fluid is very appealing, forming an effective and stable anastamosis between obstructed lymphatic vessels and the venous system is technically very difficult. The trials that report on these techniques are often very small, the follow-up is often short and there is inadequate information about what happens to the patients in cases where the surgery was ineffective. A paper entitled, Microsurgical lymphovenous anastomosis for treatment of lymphedema: a critical review(1) was published from the Mayo Clinic several years ago and the authors followed their patients for an average of three years after the surgery. Their trial was also small, involving only 18 patients. The patients were mixed, some had secondary lymphedema, some had filariasis and some had primary lymphedema. 14 patients were evaluated and of these 14, 5 had improvement, 5 were unchanged and 4 had progression of their lymphedema at the time of last follow-up. The authors concluded that there was no objective evidence supporting the value of microsurgical treatment for lymphedema.

   One of the main concerns about using surgical approaches to the management of lymphedema is the probability of making the condition significantly worse. Patients with lymphedema have enough problems without making the condition worse with an invasive surgical procedure. One of the critical questions that must be addressed by these studies is the complication rate and the extent of worsening of edema experienced by these patients. There will be discussion of the surgical approach to the treatment of lymphedema at the upcoming NLN conference and I look forward to learning of any new and effective treatments.

   One of the more exciting possibilities is the use of growth factors that selectively stimulate the growth of lymphatic vessels. These growth factors have been identified recently and research is ongoing to understand how they work and whether they will be of benefit in the treatment of lymphedema. While this is only in the earliest stages of research, such technology offers the promise of effective therapy in the future.

   One of the problems with these by-pass surgeries is that the by-pass tract becomes blocked soon after the surgery. We learned this while studying cardiac by pass surgeries and surgeries to by pass obstructed veins in the legs. Since obstruction of the lymphatic by pass channels also appeared to occur, anastomoses were performed in dogs to determine the rate of blockage of lymphatic venous by-pass surgeries (2). By 8 months, 75% of the anasotmoses were blocked. The authors concluded that the rate of blockage was high; therefore, chances of success were better when several anastomoses were performed in the early stages of lymphedema, before significant tissue fibrosis and complete loss of lymphatic valvular function occurred.

   There have been relatively few papers written about these techniques from centers in the United States in recent years. Many of the publications have come from Russia, China and Japan.

   In a Russian study, 152 patients were followed for a period of 2 to 6 years after surgery to form an anastomosis between the lymphatic and venous systems (3). Approximately 2/3 of the patients demonstrated improvement; however, 1 of 3 patients did not improve or got worse. Only the abstract is available in English and the authors did not report the percent of overall percent changes in limb volume. In addition, they did not discuss the whether complications of the surgery were observed.

   In China, 110 patients with lymphedema of the were treated with microsurgery forming an anastomosis between lymphatics and veins (4). Ninety-eight patients with lymphedema of the extremities were followed-up for 26 months and about 2/3 of the patients demonstrated improvement. In those patients, the average reduction in circumference of the affected limb was 59%. However, there was no discussion of the long-term effects of the surgery or the results or complications among the patients that did not respond to the surgery.

   In Australia, 52 patients were treated by microlymphatic surgery (5). Significant improvement was observed in 22 patients (42 percent), with an average reduction of 44 percent of the excess volume. However, long-term results were not available. In addition, the authors concluded that better results can be expected with earlier operations because the patients usually have less lymphatic disruption.

   A recent article from Japan, reports the use of microsurgical lymphaticovenous implantation for the treatment of chronic lymphedema (6). This technique involves placing a lymphatic shunt in the area of obstruction. Only 8 patients were treated with this method and larger studies are need to assess the long-term benefit of this technique.

   One of the main concerns about using surgical approaches to the management of lymphedema is the probability of making the condition significantly worse. One of the critical questions that must be addressed by these studies is the complication rate and the extent of worsening of edema experienced by these patients. There will be discussion of the surgical approach to the treatment of lymphedema at the upcoming NLN conference and I look forward to learning of any new and effective treatments.

   One of the more exciting possibilities is the use of growth factors that selectively stimulate the growth of lymphatic vessels. While this is only in the earliest stages of research, such technology offers the promise of effective therapy in the future.