dustin borg, me patrick henley, bme ali husain, bme nick stroeher, bme advisor: dr. joel barnett

Dustin Borg, MEPatrick Henley, BMEAli Husain, BMENick 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 moleculesThe 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/

ProblemPlaque 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 arteriesHeart disease is America's major killerSevere 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.ynhh.org/healthlink/cardiac/cardiac_9_00.htmlhttp://www.coconut-info.com/diet_and_disease.htm

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

http://www.2sourcesofcholesterol.com/2sourcesofcholesterol/images/your_cholesterol/artery_plaque.jpg

Current Known Effects of Plasma on Cell TissuePlasma 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 plasmaThe Development of a Smart-Scanning Probe for the Plasma Needle, Ewout van der Laan

Project GoalDesign and Build a Working Plasma-catheter Construct functioning basic plasma needle prototypeDesign catheter Build catheter design incorporating functioning plasma needleCharacterize plasma-catheter prototypeRefine design to suit surgical needs

Requirements to Meet GoalsFlexibility: Tungsten electrodeBending catheter should not affect gas helium flowInsulating material

Safety:Minimal He flowPossibly requiring a separating material between plasma discharge and biological tissueNo blood flowing into catheter and no bubbles going into bloodstream

Our Progress So FarFaculty ConsultationWelding ExpertsHigh Frequency Electronics TechnicianCardiovascular Surgeon Electrode ResearcherDesign of Test Rig PrototypeArranging for Experimental SetupCommissioning of Glass Test Rig to SpecificationsArranging for Suitable Lab SpaceAcquisition of Necessary Electronic ComponentsAcquisition of He Flow EquipmentPurchasing of Other Necessary MaterialsDesign of Catheter Research into Operating ParametersBrainstorm Potential DesignsSelection of Best Design

Plasma Needle Operating CharacteristicsRF Frequency = 13.56 MHz (universal)P-P RF Voltage ~ 200 - 400 VPower Level ~ 100 400 mWNeedle Resistance = 1.1 ohm Needle Capacitance = 28.8 pFPlasma Resistance = 2 ohms(Plasma discharge purely resistive) Helium Flow = 0.1L/minMinimum Ignition Voltage = 250 V

Plasma Needle Prototype Experimental Setup

First Test RigDiameter of Tungsten Needle = 0.3mmLength = 5cmMaterial: Glassglassteflon coatingtungstenheliumRF5 cm2 mm

Revised Test Rig Modifications:Lengthened Input OpeningEnlarged Input Diameter

50 mm35 mm2 mm58 mm Electrode coatingNeedle coatingElectrode Hypodermic Needle Helium flow25 mm 4.3 mmShaftLength: 5 cmOuter Diameter: 4 mmInner Diameter: 2 mmElectrode Diameter: .3 mm

Teflon Needle InsulationStainless SteelHypodermic needleTungsten electrodeTeflon Electrode Insulation10 mm Teflon overlap25 mm needle tipDetailed View of Electrode Input

Function Generator(Courtesy of our Dutch colleagues)

RF Signal: 13.56 MHz

Max Power Output: 10 W

Variable MatchboxZ-11 QRP Automatic Antenna Tuner

Manufacturer: LDG Electronics Inc.Size: 5.0 x 6.5 x 1.3 enclosureTunes 6-800 ohm loadsTuning time: .1-3 sec1.8 30.0 MHz CoveragePower range: .1-30 W

Z-11 QRP Automatic Antenna Tuner

Config: Switched L networkMicroprocessor ControlledInductor range: 20 uHCapacitor range: 2700 pf

Ramsey QRP Power MeterContinuous measurement from 1Watts to 50WattsAllows measurement of both forward and reflected power

http://www.ramseyelectronics.com/cgi-bin/commerce.exe?preadd=action&key=PM10DC

Helium Source and Flow MeterHelium on hand in EE Welding LabFlow meter is calibrated for really small flowsExternal needle valve possibly needed

Costs

ItemCostRF Generator$0Ramsey QRP Power Meter$164.95LDG Z-11 QRP Autotuner$125.95Cole-Palmer Flow Meter$179Electric Connections$23.24Tungsten Wire$3.55Teflon Tubing$5Hypodermic Needles$66Glass Test Rig$50Sum$617.69

Catheter Designs 5 cm Electrode coatingElectrode Hypodermic Needle 20 mm35 mm2 mmHelium flow4.3 mmFlexible Catheter(end view) Potential Internal Catheter Configurations

Immediate Goals(through beginning of April)Construction of plasma needle prototypeAssess need for external needle valveConstruct experimental setup in EE Welding LabRun simulation and make necessary modificationsContact Coordinating GroupClarify necessary parameters for plasma characterizationConfirm parameters for final catheter design for use in rabbit test subjects Establish communication with researchers planning to conduct animal testingCatheter Design WorkContinue discussions with local medical professionalsMeet with Vanderbilt Catheter Lab specialistsConstruct catheter prototypeConduct laboratory testing to characterize catheter

TimelineDecember

January

February

March

April

Gas Plasma & Catheter ResearchConstruction of Functioning Plasma Needle PrototypeResearch & Design of CatheterCatheter ConstructionPhysical Testing and Refinement of Plasma Catheter

Our Dutch CounterpartsWillem-Jan van Harskamp, Applied PhysicsVivian Roode, BMEGijs Snieders, BMEM. van Vlimmeren, BME

Advisor: Dr. Eva Adamowicz

Level of Development of Plasma Needle TechnologyCompleted:Evaluation of the electrical characteristics of the plasma needleSensing the gap width by monitoring the discharge power consumptionAdapted positioning sensor Current:Design Plasma-CatheterFuture:Testing in animal blood vessels

Connects two circuits together via a network in such a way that the maximum transfer of energy occurs between the circuits. The max transfer occurs when the impedances of those two circuits are equal. (source and plasma)Tunable