Transcervical Thymectomy for Myasthenia Gravis

Myasthenia gravis is an autoimmune neurologic disease that results when the thymus, a normally dormant gland in the chest, begins producing antibodies that interfere with the muscles' ability to contract. The symptoms may include droopy eyelids; double vision; weakness in the face, neck, arms and legs; and/or difficulty in swallowing. Myasthenia gravis can have a serious impact on the simple activities of daily living.

Thymectomy
Most experts agree that removing the thymus gland (thymectomy) improves the course of the disease by reducing or eliminating the symptoms. However, improvement may take months or years. Thymectomies traditionally have been performed by dividing the breastbone down the middle of the chest, the same incision used by cardiac surgeons for heart surgery. Because of the extent of the incision used with the traditional approach and several weeks of recovery time, many people with myasthenia wait until their illness has progressed before having the operation.

Minimally Invasive Transcervical Thymectomy
When the thymus is removed through a neck incision alone, the operation is called a transcervical thymectomy. Surgeons first performed the transcervical thymectomy in 1912 for a patient with myasthenia gravis. A newer technique is used by Washington University thoracic surgeons. This technique involves a 1 1/2-inch incision at the bottom of the neck, just above the breastbone [sternum]. No bone is divided and only the skin is cut. A special retractor was developed to perform the surgery. This device allows the surgeon to see the thymus gland directly from the neck without the need to open the chest. G. Alexander Patterson, MD, Bryan F. Meyers, MD, and other thoracic surgeons at Washington University School of Medicine and Barnes-Jewish Hospital, now have performed more than 200 of these procedures.

Contraindications of the Transcervical Thymectomy
The transcervical approach should not be used for patients with thymoma (tumor of the thymus) and should be done only by surgeons trained and experienced in this highly specialized procedure.

Method
Washington University thoracic surgeons perform the transcervical thymectomy through a 1 1/2-inch incision in the lower portion of the neck. With the use of special instruments, the surgeon is able to see into the chest and remove the thymus gland. Because the operation is performed through a small incision, and because no major muscles, ribs or other bones are injured, recovery is rapid and there are no postoperative restrictions on activity.

What to Expect
A neurologist trained in the care of myasthenia gravis evaluates all patients considering thymectomy to assess their symptoms and the extent of their disease. The neurologist assesses whether the patient would benefit from a medical treatment called plasmapheresis before undergoing surgery. In patients with severe weakness, plasmapheresis is considered before surgery to reduce the level of harmful antibodies in the blood. The removal of these antibodies improves muscle strength before the operation. Patients are admitted to the hospital either the day before surgery or the day of surgery, depending upon their health status. The surgery takes approximately 90 minutes to complete. Our operating room staff members specialize in thoracic surgery and are experts in caring for the thymectomy patient. After surgery, the patient is monitored in the recovery area until stable and then is moved to the Thoracic Surgery Observation Unit. This unit has nurses specially trained in the care of the thymectomy patient. Patients are discharged directly from the observation unit to home, usually the next day. The average time from surgery to discharge is 24 to 36 hours. Patients have a single follow-up appointment with the surgeon and then are released with follow-up care to be provided by their neurologist.

Advantages of the Transcervical Thymectomy
Patients with myasthenia gravis who choose transcervical thymectomy are more likely to have their thymus gland removed early in their disease. Therefore, these patients’ symptoms are less likely to progress. The standard approach to thymectomy uses a chest incision and requires an average hospital stay of five to seven days, while the transcervical thymectomy allows the patient to leave the hospital the following day. Furthermore, following the transcervical approach, patients can return to normal activities within a day or two, whereas with the open-chest approach, recovery time is a matter of weeks. Transcervical thymectomy patients experience less pain and fewer postoperative complications than do patients who require the open chest procedure.

Results
Patients have ranged from 12 to 71 years of age. Before surgery, the patients had an average Osserman score of 2.65 (meaning they have slight-to-moderate generalized weakness or swallowing difficulties). No patient required blood transfusions or postoperative respiratory support. Seventy-one percent of the patients had a very significant improvement (no generalized weakness and no requirement for the medication Mestinon). Twenty-one percent of patients showed modest improvement, and only 8 percent showed no improvement at all.

Careful follow-up of patients undergoing the transcervical approach has been obtained for up to 10 years. The results are equivalent to those seen after open-chest procedures. Immediately following the operation, the patient continues to take the same medication as he or she was taking before the operation. However, over the following months and years, the majority of patients regain normal muscle strength and many experience complete remission — that is, no weakness and no requirement for medication. The main value of the transcervical thymectomy is to encourage the early removal of the thymus gland in patients with myasthenia gravis, thus increasing their chance for complete remission.

For a thoracic surgery consultation, call (888) 287-8741.