**4.2 Radionuclide seed implantation**

Radionuclide seed such as 125I、103Pd、198Au implantation has been used in lots of clinical departments. Mostly 125I seeds (Figure 13) have been chosen as the proper one. Iodine-125 delivers a higher radiation dose to the patient due to the half life of 60 days and 125I seeds planted have been used in the therapy of solid tumors.

Fig. 13. 125I seed is used in the therapy of solid tumor by implantation.
