MRI Infusion Pump Ryan Augustine Megan Buroker Tim Eng Nate Gaeckle Gordy Lawrence Christine Weisshaar

Background Information Magnetic Resonance Imaging Protons from water molecules Gadolinium (contrast) controls the water molecules Saline flushes Bolus vs. Infusion Spectris Solaris Wastes Gadolinium and Saline Unable to supply different flow rates while in use Creates a large gap between bolus and infusion

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Product Requirements No Ferrous Metals can be exposed Must supply a flow rate between .25 mL/s and 5 mL/s Control with ease Change infusion flow rates Computer software Maintain sterility Move on to infusion immediately after bolus Decrease waste of Gadolinium and Saline Reliability 2-3 protocols per day Daily Usage

Proposed Design

Finger Pump Fingers oscillate to transport fluids Operated by a camshaft or solenoid Easy to keep sterile

Gear Pump Simple mechanism Gears rotate to transport fluids Difficult to maintain sterility

Peristaltic Pump Motor rotates segments that move fluids Creates a vacuum Easy to keep sterile Proved itself in medical applications

Motor Bell-type armature motor Non-ferrous Symmetrically balanced permanent magnet Speed linearly proportional to voltage

Problems and Future Considerations Magnetic shielding for servo motors MuShield Calculations for desired operation Torque needed by motor Diameter of tubing Properties of the two fluids

Alternatives Motor Driven Pump Dielastic Actuators Often contains metal material Cannot be next to scanner Dielastic Actuators Malleable capacitors Elongates  used to propel gears New, not on market

Our Solution Stand: Holds standard size bags of saline and contrast at top Pump attaches to bag Tubing attaches to pump Come together with a Y connector Both fluids flow to patient To Patient Pumps Saline Contrast Y Connector

The Pump… Peristaltic Pump Aluminum or titanium rollers Rollers propelled by gears Gears driven by pressure acting as motor Air, Water, Nitrogen, Oxygen, CO2

Gears to control roller spin rate Broader View: Pressure To Patient Saline Line Contrast Line Gears to control roller spin rate Rollers

Problems MRI interference Running cables from control room Safety of propelling gears

Advantages Saving money Set-up time reduced Preparation minimal Allows bolus & infusion to take place during same scan

Design Option 1 Use a force driven syringe pump Force source possibilities Gravity, gas under pressure, elastic materials, liquid under pressure, or dielastic actuators

Design Option 2 Peristaltic pump powered by a flywheel and gear system Allows great flexibility when choosing type of power source Minimizes potential for air bubbles Easy to sterilize Can be made with nonferrous materials

Design Option 3 System applying force to bag reservoirs. Will be difficult if not impossible to determine outflow volume with a changing bag volume. How to apply force throughout the procedure as the bag is reduced in size?

References http://www.maztravel.com/enrique/tour3.html http://www.animatedsoftware.com/pumpglos/pumpglos.htm www.medrad.com www.edmond/wheelchair.com/i_v__stands.htm