Dustin Borg, ME
Patrick Henley, BME
Ali Husain, BME
Nick Stroeher, BME
Advisor: Dr. Joel Barnett
What is Plasma?
Plasma is a state of matter with enough free charged particles so
that its dynamics are heavily influenced by electromagnetic forces.
 gaseous fluid-like mixture of ions, free
electrons,radicals and excited atoms and
molecules
The Plasma Needle uses Low-Temperature Plasma (LTP)
 small fraction of neutral particles in gas are ionized
 electrons are high energy; ions are ambient temp.
 retains neutral charge
http://solar.physics.montana.edu/martens/plasma/
Problem
http://www.coconut-info.com/diet_and_disease.htm
http://www.ynhh.org/healthlink/cardiac/cardiac_9_00.html
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Plaque can build up in blood vessels leading to infarctions, stoppage
in blood flow or possibly to heart attack
Subjects [with] cholesterol, were about two-and-a-half times more likely to
have advanced plaque blockages in their coronary arteries
Heart disease is America's major killer
Severe blockage due to arterial plaque, a clot, a spasm, or any combination of
these, may lead to a myocardial infarction, the dreaded heart attack, resulting
in cardiac dysfunction and often rapid death
http://www.2sourcesofcholesterol.com/2sourcesofcholesterol/images/your_cholesterol/artery_plaque.jpg
Possible Solution?
Cholesterol builds
underneath the
endothelium tissue at
early stages of arterial
blockage
Slowing – or possibly
eliminating – the buildup
of cholesterol beneath
endothelium tissue can
hypothetical lower the
risk of arterial blockage
The Development of a Smart-Scanning Probe for the Plasma Needle, Ewout van der Laan
Current Known Effects of
Plasma on Cell Tissue
Plasma Needle likely damages CAM proteins so that cholesterol is not
able to bind to the endothelium cell wall as easily, therefore
meaning less cholesterol builds in artery
Destruction of CAM  proliferation of free radicals (O, OH);
previous research shows that plasma does disperse free radicals
in a localized area. Amount of free radicals at a specific point
depends on the distance from the plasma
Project Goal
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Design and Build a Working
Plasma-catheter
– Construct functioning basic plasma needle
prototype
– Design catheter
– Build catheter design incorporating
functioning plasma needle
– Characterize plasma-catheter prototype
– Refine design to suit surgical needs
Requirements to Meet
Goals
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Flexibility:
– Tungsten electrode
– Bending catheter should not affect gas helium flow
– Insulating material
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Safety:
– Minimal He flow
– Possibly requiring a separating material between plasma
discharge and biological tissue
– No blood flowing into catheter and no bubbles going into
bloodstream
Our Progress So Far
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Faculty Consultation
–
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Welding Experts
High Frequency Electronics Technician
Cardiovascular Surgeon
Electrode Researcher
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Commissioning of Glass Test Rig to Specifications
Arranging for Suitable Lab Space
Acquisition of Necessary Electronic Components
Acquisition of He Flow Equipment
Purchasing of Other Necessary Materials
Design of Test Rig Prototype
Arranging for Experimental Setup
Design of Catheter
– Research into Operating Parameters
– Brainstorm Potential Designs
– Selection of Best Design
Plasma Needle Operating
Characteristics
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RF Frequency = 13.56 MHz (universal)
P-P RF Voltage ~ 200 - 400 V
Power Level ~ 100 – 400 mW
Needle Resistance = 1.1 ohm
Needle Capacitance = 28.8 pF
Plasma Resistance = 2 ohms
 (Plasma discharge purely resistive)
 Helium Flow = 0.1L/min
 Minimum Ignition Voltage = 250 V
Plasma Needle Prototype
Experimental Setup
First Test Rig
glass
teflon coating
5 cm
2 mm
RF
tungsten
Diameter of Tungsten Needle = 0.3mm
Length = 5cm
Material: Glass
helium
Revised Test Rig
Modifications:
1) Lengthened Input Opening
2) Enlarged Input Diameter
58 mm
25 mm
35 mm
50 mm
2 mm
Needle
coating
Hypodermic
Needle
Hypodermic Needle
4.3 mm
Electrode
Electrode
coating
Shaft
Length: 5 cm
Teflon Coating for Needle
Outer Diameter: 4 mm
Glass
Inner Diameter: 2 mm
Electrode's Teflon Coating
Electrode Diameter: .3 mm
Tungsten Electrode
Helium flow
Detailed View of
Electrode Input
Teflon Needle
Insulation
Tungsten electrode
10 mm Teflon overlap
25 mm needle tip
RF
Stainless Steel
Hypodermic needle
Teflon Electrode
Insulation
Function Generator
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RF Signal: 13.56 MHz
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Max Power Output: 10 W
(Courtesy of our Dutch colleagues)
Variable Matchbox
Z-11 QRP Automatic Antenna Tuner
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Manufacturer: LDG Electronics Inc.
Size: 5.0 x 6.5 x 1.3” enclosure
Tunes 6-800 ohm loads
Tuning time: .1-3 sec
1.8 – 30.0 MHz Coverage
Power range: .1-30 W
Z-11 QRP Automatic Antenna Tuner
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Config: Switched “L” network
Microprocessor Controlled
Inductor range: 20 uH
Capacitor range: 2700 pf
Ramsey QRP Power Meter
 Continuous measurement from 1µWatts to 50Watts
 Allows measurement of both forward and reflected power
http://www.ramseyelectronics.com/cgi-bin/commerce.exe?preadd=action&key=PM10DC
Helium Source
and Flow
Meter
 Helium on hand in EE
Welding Lab
 Flow meter is calibrated for
really small flows
 External needle valve
possibly needed
Costs
Item
Cost
RF Generator
$0
Ramsey QRP Power Meter
$164.95
LDG Z-11 QRP Autotuner
$125.95
Cole-Palmer Flow Meter
$179
Electric Connections
$23.24
Tungsten Wire
$3.55
Teflon Tubing
$5
Hypodermic Needles
$66
Glass Test Rig
$50
Sum
$617.69
Catheter Designs
5 cm
35 mm
2 mm
Flexible Catheter
20 mm
Electrode
coating
Hypodermic
Needle
4.3 mm
Helium flow
Electrode
Potential Internal
Catheter Configurations
(end view)
Immediate Goals
(through beginning of April)
1. Construction of plasma needle prototype
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Assess need for external needle valve
Construct experimental setup in EE Welding Lab
Run simulation and make necessary modifications
2. Contact Coordinating Group
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Clarify necessary parameters for plasma characterization
Confirm parameters for final catheter design for use in rabbit
test subjects
Establish communication with researchers planning to conduct
animal testing
3. Catheter Design Work
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Continue discussions with local medical professionals
Meet with Vanderbilt Catheter Lab specialists
Construct catheter prototype
Conduct laboratory testing to characterize catheter
Timeline
December
January
Gas Plasma &
Catheter Research
Research & Design
of Catheter
February
March
April
Catheter
Construction
Construction of
Functioning Plasma
Needle Prototype
Physical Testing and Refinement
of Plasma Catheter
Our Dutch Counterparts
Willem-Jan van Harskamp,
Applied Physics
Vivian Roode, BME
Gijs Snieders, BME
M. van Vlimmeren, BME
Advisor: Dr. Eva Adamowicz
Level of Development of
Plasma Needle Technology
Completed:
 Evaluation of the electrical characteristics of the plasma
needle
 Sensing the gap width by monitoring the discharge power
consumption
 Adapted positioning sensor
Current:
 Design Plasma-Catheter
Future:
 Testing in animal blood vessels