Background]-In a combined endoscopic third ventriculostomy (ETV) and endoscopic tumor biopsy (ETB) procedure, an optimal tool trajectory is mandatory to minimize trauma to surrounding cerebral tissue.[Objective]-This paper presents wire-driven multi-section robot with push-pull wire. The robot is tested to attain follow-the-leader (FTL) motion to place surgical instruments through narrow passages while minimizing the trauma to tissues.[Methods]-A wire-driven continuum robot with six sub-sections was developed and its kinematic model to achieve FTL motion was proposed. An accuracy test to assess the robot's ability to attain FTL motion along a set of elementary curved trajectory was performed. We also used hydrocephalus ventricular model created from human subject data to generate five ETV/ETB trajectory and conducted a study assessing the accuracy of the FTL motion along these clinically desirable trajectories.[Results]-In the test with elementary curved paths, the maximal deviation of the robot was increased from 0.47 mm at 30 degrees turn to 1.78 mm at 180 degrees in a simple C-shaped curve.

The integrated design simplifies the robotic system and facilitates use of the robot. Compared with the commercialized robots, the proposed MIS robot achieves similar functions and features but with a smaller size and less weight.

This hand-eye coordination model provides evidence for robotic design, surgeon training, and robotic initialization to achieve dexterous and safe manipulation in surgery.

Purpose: The challenge of catheter‐tip visualization for interstitial needle placement in gynecologic brachytherapy remains unmet. We evaluate an approach to actively track tip locations and visualize catheter trajectories and surrounding soft‐tissue in real‐time during an intervention. The methods include development of clinical needles with magnetic resonance (MR) tracked microcoils, an MR tracking and rapid imaging sequence and integration with a graphical workstation for visualization. Methods: An active tracking device was built based on a commercial catheter which consists of a hollow tube and a central needle with microcoils at the distal end. An MR tracking sequence was developed (isotropic resolution: 0.6 mm, frame rate: 40 updates/sec). It runs continuously during navigation or interleaves with real‐time imaging (3 frames/sec), where image position/orientation are automatically set to provide visualization of anatomy around the catheter. The catheter‐tip position/orientation was passed to the workstation for visualization. Needle shapes were superimposed on pre‐acquired high‐resolution images or on the intra‐procedural images. Results: MR‐guided catheter placement procedures were conducted in a gel phantom and an animal model. High‐resolution 3D MR scans were acquired and loaded into the workstation for navigation. During insertion, the catheter tips were visualized advancing on a 3D anatomic model and on assigned planes. Real‐time imaging with slice continuously updating at the instantaneous tip positions was also performed. Both methods served well to guide catheter placement. After insertion, complete catheter trajectories were rendered by recording tip positions as needles were pulled out and overlaid on the images, to support treatment planning. Conclusion: We demonstrated the feasibility of active catheter tracking and visualization in MR‐guided brachytherapy. This will facilitate accurate and time‐efficient catheter insertion by providing on‐line identification of catheter position, and visualization of anatomy ahead of the catheter tip. This enables identifying preferential paths to target locations, and reduces the risk to critical organs. Funding sources: NIH P41 EB015898; AHA 10SDG261039