Thymectomy in the adult mouse. A new approach.

: Adult mice were thymectomized using a retrosternal approach. The sternothyroid muscle was divided, the sternum was elevated, and the lobes of the thymus were removed by aspiration. The technique was used to thymectomize about 300 mice of several strains. The incidence of thymic remnants was less than 1% and losses from surgery were less than 10%.