1. Robotic Needle End Arm Effector for Integration With CT Scan
Team Members:
David Sun
Chris Willingham
Advisor:
Dr. Bradford Wood

2. Project Statement
A robotic system which reduces radiation exposure during CT assisted fluoroscopy while providing greater accuracy and precision is feasible (Cleary and Nguyen, 2001).
One of the primary limitations to this system is its ability to place instruments with the “touch” that a skilled physician provides (Stoianovici and Cleary 2002).

3. Problem Definition
CT assisted fluoroscopy allows surgical procedures such as tissue biopsy and ablation to be performed with several advantages over traditional techniques (Solomon 2002):
The method allows visualization for interventional procedures
Procedures are performed in real time
The process is faster and more accurate than traditional methods
Cases show greater success rates (improved patient outcomes)
The primary disadvantage to this method is the radiation exposure received by the physician during the procedure:
2mGy per procedure
500mSv annual limit
Each physician is thus limited to 4 procedures per year

4. Background

5. Project Goal
A successful resolution to this problem will remove the physician from the operating suite while addressing three main factors:
It will allow for respiratory motion in the craniocaudal axis.
It will provide an interface for various instruments at a common joint.
It will allow 6+ degrees of freedom during instrument placement, and free range of motion after placement.

6. Proposed Solution
We propose to modify an existing heart stabilizer to serve as the end arm effector for a surgical robot, providing and instrument which will:
Accommodate a variety of needle gauges
Provide an instrument which is rigid during needle placement, yet unlocks rapidly after placement to allow appropriate ROM
Interface with a specific robotic arm, but be easily adaptable to fit other systems

7. Procedural Example
Hepatitis C virus affecting 175 million people globally
80% develop chronic hepatitis C
8,000 – 10,000 deaths annually in US
No accurate noninvasive markers of the disease
Liver biopsy is used to establish the stage of the liver disease
Majority of patients with chronic hepatitis C will require a liver biopsy

8. Status Weekly conference call with our advisor Literature review
Patent search for similar devices (micropat.com)
Obtaining Medtronic robotic arm
Obtaining FlexSite device (Heart Stabilizer)
Obtaining biopsy needles (17 & 22 gauge)
Training SolidEdge program for future CAD design
Updated all information on website

9. System Flowchart

10. Future Work
Appointment with Dr. Lee Gordon to observe biopsy for operational constraints
Continue modification of heart stabilizer to interface with the robotic arm—possible cable attachments, electronic locking
Consult with machine shop for possible interface solutions
Produce a liver phantom via silicon gel polyurethane
Consult with Dr. Bob Galloway for modifications to proposed solution
Use SolidEdge™ 2002 to model end effector for prototype purposes
Prototype, testing, and early FDA requirements

11. Conclusion Current Situation? Problems? Chances of Success?
Finished research and brainstorm phase
Continuing design and modifications
Continue consultation with surgeons and engineers for feedback
Refine possible solutions
Problems?
Interfacing with multiple robotic arms
Needle interface
Electrical interface necessary for performance
Chances of Success?
Design idea is progressing well
Limiting design to a mechanical prototype to obtain testable results

12. References
Solomon, Stephen, et. al. Robotically Drive Intervention: A method of Using CT Fluoroscopy without Radiation Exposure to the Physician. Radiology Volume 225-Number 1.
Stoianovici, Dan, et. al. AcuBot: A Robot for Radiological Interventions. IEEE-TR&A.
Cleary, Kevin, et. al. State of the Art in Surgical Robotics:Clinical Applications and Technology Challenges. Computer Aided Surgery, August 2001.
Saadeh, Sherif, et. al. The Role of Liver Biopsy in Chronic Hepatitis C. Hepatology, Volume 33, 2001.

13. Contacts David Sun david.d.sun@vanderbilt.edu Chris Willingham