Teleoperated and Automated Control of a Robotic Tool for Targeted Prostate Biopsy.

This work presents a robotic tool with bidirectional manipulation and control capabilities for targeted prostate biopsy interventions. Targeted prostate biopsy is an effective image-guided technique that results in detection of significant cancer with fewer cores and lower number of unnecessary biopsies compared to systematic biopsy. The robotic tool comprises of a compliant flexure section fabricated on a nitinol tube that enables bidirectional bending via actuation of two internal tendons, and a biopsy mechanism for extraction of tissue samples. The kinematic and static models of the compliant flexure section, as well as teleoperated and automated control of the robotic tool are presented and validated with experiments. It was shown that the controller can force the tip of the robotic tool to follow sinusoidal set-point positions with reasonable accuracy in air and inside a phantom tissue. Finally, the capability of the robotic tool to bend, reach targeted positions inside a phantom tissue, and extract a biopsy sample is evaluated.

Modeling and Operator Control of a Robotic Tool for Bidirectional Manipulation in Targeted Prostate Biopsy.

This work introduces design, manipulation, and operator control of a bidirectional robotic tool for minimally invasive targeted prostate biopsy. The robotic tool is purposed to be used as a compliant flexure section of active biopsy needles. The design of the robotic tool comprises of a flexure section fabricated on a nitinol tube that enables bidirectional bending via actuation of two internal tendons. The statics of the flexure section is presented and validated with experimental data. Finally, the capability of the robotic tool to reach targeted positions inside prostate gland is evaluated.

Integrating robot-assisted ultrasound tracking and 3D needle shape prediction for real-time tracking of the needle tip in needle steering procedures.

BACKGROUND: Needle insertions have been used in several minimally invasive procedures for diagnostic and therapeutic purposes. Real-time position of the needle tip is an important information in needle steering systems. METHODS: This work introduces a robot-assisted ultrasound tracking (R-AUST) system integrated with a needle shape prediction method to provide 3D position of the needle tip. The tracking system is evaluated in phantom and ex vivo beef liver tissues. RESULTS: An average error of 0.60 mm was found for needle insertion tests inside the phantom tissue. The R-AUST integrated with shape prediction in the beef liver tissue was able to track the needle tip with an average and maximum error of 0.37 and 0.67 mm, respectively. The average error reported in this work is within the mean allowable needle placement error (<2.7 mm) in targeted procedures. CONCLUSIONS: Integration of R-AUST tracking method with needle shape prediction results in a reasonably accurate real-time tracking suitable for ultrasound-guided needle insertions.

Steering a Tendon-Driven Needle in High-Dose-Rate Prostate Brachytherapy for Patients with Pubic Arch Interference.

High-dose-rate brachytherapy (HDR BT) is a radiation therapy that places radioactive sources at cancerous tissue using needles. HDR BT offers better dose conformality and sparing of clinical structures, lower operator dependency, and fewer acute irritative symptoms compared to the other form of BT (low-dose-rate (LDR)). However, use of HDR BT is limited for patients with pubic arch interference, where the transperineal path to the prostate is blocked. This study aims to introduce a tendon-driven needle that can bend inside tissue to reach desired positions inside prostate. Initial experiments in a phantom tissue showed the feasibility of the needle to get around the pubic arch for placement at hard-to-reach target positions.