Team Members

1
Team Members

• BME 400
• Thomas Chia
• Jason Ethington
• Brent Geiger
• Kawai Chan

2
Client

• Bhudatt Paliwal Ph.D.
• Professor of Human Oncology and Medical Physics
• Director of Radiation, Oncology, Physics
• University of Wisconsin Hospital Radiation
  Oncology
• Tiezhi Zhang Ph.D.
• Assistant ResearcherHuman Oncology
  DepartmentUniversity of Wisconsin, Madison
•                   

3
Advisor

• Justin Williams Ph.D.
• Associate Professor
• Department of Biomedical Engineering

4
Abstract

• The goal of this device is to measure breathing
  patterns of lung cancer patients. Consistent
  breathing patterns are necessary for successful
  radiation treatment. The device uses a technique
  called resistance pneumography to detect a
  patients breathing pattern and convert it into
  an electrical signal. The signal is then
  acquired, processed, and displayed on a PDA
  device allowing the patient to practice
  consistent breathing patterns or monitor their
  breathing while undergoing radiation treatment.

5
Background

• 4-D Tomotherapy used to treat lung cancer
  patients
• Radiation concentrates on moving target tissues
• 3-Dimensional imaging of target tissues required
• Added time dimension

6
Design Motivation

• Tomotherapy treatment requires a consistent
  patient breathing pattern
• A consistent and repeatable breathing pattern
  would allow for more accurate tissue targeting
• Consistent breathing patterns would maximize
  cancerous tissue destruction and minimize healthy
  tissue damage

7
Design Criteria

• Design device to measure and display patients
  breathing pattern
• Display patients real-time breathing pattern
  against a guiding cycle
• Device must be small and portable
• Still function as a training device for used
  outside of treatment
• Can be used to monitor patient breathing while
  undergoing Tomotherapy treatment

8
Final Design

• Continuation from BME 301
• Final design includes modifications to three
  major components of the design
• 1. Sensing hardware
• 2. PDA and Data acquisition
• 3. User Interface and display of information

9
Previous Work Sensing Hardware
10
Sensing Hardware

• Miniature linear potentiometer attached to strap
  around patients chest
• Circumference of chest increases during
  inhalation and extends wire
• Extension of wire changes the resistance of the
  potentiometer
• Change is resistance produces an analog voltage
  output proportional to the length of wire
  extension

11
Sensing Hardware

• Modified strap to be as small as possible
• Only potentiometer attached to strap
• Power supply and controls away from chest strap
• Elastic portion of strap to increase accuracy

12
Data Acquisition

• Asus MyPal A620
• Windows PocketPC
• 400MHz Intel XScale
• Built-in Compact Flash (CF) drive
• Supports LabVIEW PDA

13
Data Acquisition

• Compact Flash Data Acquisition Card
• 24-bit Analog Input
• 2.5V built-in reference voltage (eliminates
  battery)
• Supports LabVIEW PDA

14
User Interface and Display

• LabVIEW 7.1 software program split into two
  parts

1) Guiding cycle acquisition -allows technicians
to capture the patients normal breathing pattern
and save it to a file
2) Patient Training -allows patient to view real
time breathing pattern against guiding cycle
15
Design Difficulties

• Defective data acquisition card was shipped to
  team
• Sent back to manufacturer
• Delayed LabVIEW PDA software development

16
Future Work

• Acquire working data acquisition card
• Meet with WARF for disclosure meeting
• Begin Human Trials
• Test device during Tomotherapy treatment

17
Special Thanks

• Dr. Bhudatt Paliwal
• Professor of Human Oncology Medical Physics
• Director Radiation
  Oncology Physics                        
• Tiezhi Zhang
• Assistant Researcher
• Human Oncology Department
• Justin Williams
• Professor Biomedical Enginneering
• University of Wisconsin Madison
• Adam Sweet
• National Instruments Consultant