Guided Biopsy Needle

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Guided Biopsy Needle

• Group 21
• Swati Shimpi
• Arya Zahedi
• Mentors
• Dr. Sam Bhayani
• Stephen Dryer
• Instructor
• Dr. Joseph W. Klaesner
• BME 401 Progress Report Presentation
• April 20th, 2005

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Project Overview

• Objective
• To design a device, for clinical use, which
  enables renal biopsy to be performed with greater
  efficiency.
• Rationale
• Reduce the failure rate of current biopsy
  procedures to more effectively diagnose Renal
  Cell Carcinoma (RCC).
• Challenge
• To confirm renal penetration by distinguishing
  between renal parenchyma and perirenal adipose
  tissue.

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Project Overview

• Current Biopsy Procedures
• Blind biopsy (500)
• Ultrasound CT or guided biopsy (1000-1500)
• Laparoscopic biopsy (20,000-25,000)
• Problems
• Renal confirmation
• Repeated procedures
• Risk of bleeding
• Potential costs

Source Dr. Bhayani, Wash U Division of Urologic
Surgery
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Guided Biopsy Needle

• Solution/Need
• Smart Biopsy Needle
• Confirmation of Kidney entrance
• Less risk of bleeding
• Real time measurements
• Specifications
• Guide biopsy needle via bioelectric probe
• Biopsy probe should provide real time
  measurements
• Probe should easily function in clinical setting
• Be able to penetrate at least 5 cm into tissue in
  a minimally invasive fashion at its tip
• Needle material should be bio-compatible

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Distinguishing Between Fat and Renal Tissue
Conductivity and Relative Permittivity vs.
Frequency
Source Bronzino, Joseph D., The Biomedical
Engineering Handbook. CRC Press.
Hartford, CN. 1995. Pgs. 1338-1339.
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Final Design of Guided Biopsy Needle
Components of Guided Biopsy System

• Parallel-plate electrodes
• Thermistor
• Polyurethane insulator
• Insulating fiberglass cylinder
• Disposable biopsy needle
• Biopsy needle adapter
• Impedance probe adapter
• Handheld base
• Safety tab
• Cannula/Stylet thumb tab
• Input/Output port
• Coaxial cable
• LCR Meter (HP 4275A)

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Calculations

• Complex Impedance
• Z R (j2pfx)
• Real part R and imaginary part j2pfx
• Where x represents either C or L and
• 1/-j capacitance
• j inductance

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Calculations cont

• Having real and imaginary part
• Calculate magnitude and phase term
• Magnitude
• Phase

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Magnitude and Phase of the Impedance
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Cost Analysis

• Disposable Needle 100
• Disposable Probe 100
• Biopsy Needle Base 150
• LCR meter and analyzer 5000
• Total Cost 5500

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THANK YOU