Definition & Overview
Thymectomy is a surgical procedure to remove the thymus, a triangular-shaped gland located in the chest area, near the heart. It secretes several hormones and plays an important role in the body's immune system.
The thymus gland acts as a reservoir of T cells that protect the body from pathogens. It is very active during childhood and typically starts to shrink and lose its function as one reaches adulthood.
Thymus removal is performed as treatment of several types of medical conditions resulting from the abnormal functioning of the gland (such as myasthenia gravis) or when there’s an abnormal growth (tumour) in the gland.
Who Should Undergo & Expected Results
Thymectomy is typically performed on patients diagnosed with a condition known as myasthenia gravis, which is characterised by muscle weakness in the face, neck, arms, and legs. In this condition, the thymus gland starts producing antibodies that interfere with the muscle’s ability to contract. To avoid the debilitating effects of this disease, thymus removal can be recommended but only for those below 60 years of age and only if they exhibit advancing symptoms that greatly interfere with their daily routine.
Thymus removal is also advised for those suffering from thymoma or tumour growth in the thymus gland. Due to its close proximity to the heart and lungs, thymectomy is considered a good option to avoid the condition from metastasizing to other organs. This condition also impairs blood circulation, since the tumour can squeeze out nearby blood vessels. Several studies determined that thymectomy for thymoma treatment is most effective when done during the early onset of symptoms.
There is generally good outcome awaiting those who undergo thymus removal, especially young patients with generally healthy disposition. Hospitalization is required for a few weeks and patients are advised to avoid strenuous physical activities following the procedure.
It is important to note that some patients report worsening of symptoms right after the surgery but would gradually improve after several weeks or months. Long-term results, however, indicate improvement in the quality of life with patients being able to resume normal daily activities.
In treating myasthenia gravis, thymectomy can reduce the symptoms but the patient is still expected to take medications to achieve and maintain good results. Removing the thymus gland also improves the chances of achieving remission.
How Does the Procedure Work?
There are several approaches in performing thymectomy and the surgeon chooses the best option based on the specific condition being treated. One surgical technique is the transsternal thymectomy in which the surgeon makes one incision over the breastbone. Using a specialized tool, the breastbone is divided to locate and expose the thymus gland. The gland is then removed, along with any fat cells accumulating in the chest area, as these could contain thymus tissue with the regrowth potential. This procedure is typically done on those diagnosed with thymoma.
The surgeon could also opt to make an incision in the lower part of the neck in a procedure called transcervical thymectomy, which was originally developed to treat myasthenia gravis. It is recommended for those who have no tumour growth in the thymus gland. The breastbone is left intact and the gland is removed using a specialized tool.
Recent advancements in the field of medicine have paved the way for the introduction of minimally invasive robotic thymectomy and video-assisted thoracoscopic thymectomy. These procedures require the surgeon to make small incisions in the chest, where a camera and several small surgical tools are inserted. In robotic thymectomy, the surgeon uses robotic arms to locate and remove the thymus gland. The benefits of this technique include lesser trauma, reduced intraoperative complications, and shorter recovery period.
Possible Complications and Risks
Thymectomy is considered a major surgical procedure, which associated risks include bleeding and post-operative infections. The patient could also exhibit an adverse reaction to anaesthesia. There is also the possibility of injuring nearby organs, like the lungs and the heart that would add further complications to the procedure.
The surgeon also has to make sure not to damage the nerves near the thymus gland, since this would impair or debilitate the patient further.
Chest pains can be expected especially in the days immediately following the procedure. This would necessitate the use of medication to manage the pain.
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