Robotic MR-guided high dose rate brachytherapy needle implantation in the prostate (ROBiNSon)-a proof-of-concept...

Area of Science:

• Medical Robotics
• Radiation Oncology
• Magnetic Resonance Imaging

Background:

• High-dose-rate (HDR) brachytherapy is a crucial treatment for prostate cancer.
• Accurate needle placement is essential for effective HDR brachytherapy.
• MR-guidance offers superior soft-tissue visualization for precise targeting.

Purpose of the Study:

• To develop and assess a robotic needle implant device for MR-guided HDR prostate brachytherapy.
• To evaluate the feasibility and spatial accuracy of robotic HDR brachytherapy for intraprostatic targets.
• To quantify the accuracy of robotic needle insertion and prostate movement during the procedure.

Main Methods:

• A robotic system compatible with a 1.5 T MR scanner was utilized.
• Needle insertion was robotically controlled, guided by fused intraprocedural and diagnostic MR images.
• Spatial accuracy was assessed by measuring needle tip to target errors (NTG-error and NTT-error) and prostate deformation.

Main Results:

• The robotic device successfully placed needles to the planned depth in all five patients.
• Mean Needle Tip to Geometrical Target (NTG) error was 3.2 mm, and Needle Tip to Treatment (NTT) error was 4.5 mm.
• Prostate movement was less than 3 mm, and no acute toxicity was reported, indicating adequate feasibility.

Conclusions:

• MR-guided robotic needle insertion is a feasible technique for HDR prostate brachytherapy.
• The system demonstrated good spatial accuracy, with mean geometric error of 3.2 mm.
• The robotic approach shows promise for improving precision and safety in prostate brachytherapy.