1. Steerable Needle for Core Biopsy
Team Members
Evan Rogers – Leader
Tyler Allee – BWIG
Kristen Sipsma – BSAC
Betsy Appel – Communicator
Client
Fredrick Kelcz, Ph.D, M.D
Department of Radiology
UW Medical School
Advisor
Willis Tompkins, Ph.D.
Department of Biomedical Engineering

2. Presentation Overview
Problem Statement
Client Requirements
Background
Core Biopsy
Current Devices
Design Alternatives
Future Work

3. Problem Statement
Radiologists perform image guided biopsies and sometimes the target mass is missed, requiring the biopsy needle to be withdrawn and redirected. This process is time consuming and painful for the patient. Therefore, radiologists need a biopsy needle that contains a tip which can be steered inside the body.

4. Client Requirements Needle size <14 gauge
Must extract a core sample of tissue
Compatible for use with CT and Ultrasound
Steering must not damage adjacent tissue
Distal 1-2 cm of needle should be steerable
Must have intuitive external control mechanism
Single use device
Core VS FNA

5. Background – Biopsy Method
Local anesthetic is injected
Ultrasound is placed on surface of body to guide needle placement
Needle is inserted along line created by ultrasound to obtain sample

6. Background: Core Biopsy
Core biopsy removes 1-3 cm sample of tissue using a hollow needle
Reasons for core biopsy
Much larger sample taken than with fine needle aspiration (FNA)
Higher diagnostic accuracy rate (93% vs. 88% for FNA in diagnosing lymphomas)
Tissues Biopsied: Liver, Abdomen, Breast

7. Cook’s Quick Core Biopsy Needle
Current Devices
Rigid needle
Spring-loaded tissue capture
Rapid firing of outer sheath cuts quickly to minimize tissue damage
Single Use
Cook’s Quick Core Biopsy Needle

8. Current Device: PneumRx
Designed for FNA of lung
Co-axial design
Semi-rigid outer piece
Removable rigid inner piece
Steerable inner piece
Joystick allows steering in 2 planes

9. Coaxial Biopsy Needle Design
Semi-rigid outer needle with rigid inner needle is inserted into body
Rigid inner needle can be replaced with semi-rigid steerable needle
Passive steering due to beveled needle tip
Tissue is cut by movement of outer sheath

10. Coaxial Biopsy Needle Design

11. Joint Biopsy Needle Design
Floating elastic joint
Steerable by external push buttons
Semi rigid core bends with joint
Cutting action is provided by needle tip

12. Future Work Incorporate coaxial needle with steerable joint
Identify rigid and semi-rigid materials
Model needle mechanisms on larger scale to demonstrate properties and show how it works

13. References
Yang, Yi Jun and Damron, Timothy A., “Comparison of Needle Core Biopsy and Fine-Needle Aspiration for Diagnostic Accuracy in Musculoskeletal Lesions” ARCHIVES OF PATHOLOGY & LABORATORY MEDICINE,  Jul 2004

14. Questions?