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An operation to remove the thymus.
It usually results in remission of myasthenia gravis with the help of steroids.
Indicated when thymoma are present in the thymus.
It is suggested MG patients with no evidence of thymoma may still benefit from thymectomy.
Surgical approaches to the removal of the thymus gland include: transternal, transcervical, or transthoracic, and video assisted.
The transsternal approach is most common and uses the same length-wise incision through the sternum used for most open-heart surgery.
The transcervical approach is a less invasive procedure that allows for removal of the entire thymus gland through a small neck incision, and no difference in success in symptom improvement between the transsternal approach and the minimally invasive transcervical approach.
A thymectomy is usually carried out in adults when the thymus loses most of its functional capacity after adolescence.
The thymus but retain a small portion of its function during adulthood.
Prior to adolescence the thymus processes and matures thymocytes, which become T-lymphocytes and are released into the circulation.
Released T-lymphocytes populate the lymphoid organs until needed.
Removal of the thymus as an adult has little immediate effect on the immune system as its role has been completed.
The thymus is critical for normal development of the immune system as infants who undergo thymectomy have reduced T cell counts that do not recover to normal levels, even after years of follow and have impaired immuneresponses to childhood vaccines.
Children with congenital heart defects, who undergo thyjmectomy have a reduced naïve T cell count that is persistent to adulthood.
Thymic hypoplasia as may be seen in DiGeorge syndrome results in no T-cell education, and therefore a severe compromise in T-cell-mediated and humoral responses.
Mortality in myasthenia gravis is less than 1%.
Among adult patients who have undergone thymus removal all cause mortality and the risk of cancer were higher among patients than among controls.
Thymectomy is associated with an increased risk of autoimmune disease, lower production of CD4 positive and Cd eight positive lymphocytes than controls and higher levels of proinflammatory cytokines in the blood.