A review on the techniques used in prostate brachytherapy

Prostate brachytherapy is a validated treatment for prostate cancer. During the procedure, the accuracy of needle placement is critical to the treatment’s effectiveness. However, the inserted needle could deflect from the preset trajectory because of the needle deflection, tissue shifting caused by the interaction between the needle and soft tissue, as well as the effects of pre-inserted needles. There are significant challenges in needle placement areas, especially in prostate brachytherapy, because multiple needles are required for the effectiveness of radiation. To overcome these limitations, relevant research is carried out in mechanical, computer science, and material science areas. With the development of surgical robotics, researchers are also exploring the possibilities of raising the accuracy of needle placement with surgical-assisted robotics. This study provides a review over the last 3 decades in each of the component research areas that constitutes a surgical robotics system, including needle steering approaches, needle-tissue deformation models, path planning algorithms and different automatic level surgical robotics systems used for prostate cancer treatment, especially prostate brachytherapy. Further directions for researchers are also suggested.