Transcript MRI Infusion Pump

MRI Infusion Pump
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Ryan Augustine
Megan Buroker
Tim Eng
Nate Gaeckle
Gordy Lawrence
Christine Weisshaar
Background Information
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Magnetic Resonance Imaging
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Protons from water molecules
Gadolinium (contrast) controls the water molecules
Saline flushes
Bolus vs. Infusion
Spectris Solaris
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Wastes Gadolinium and Saline
Unable to supply different flow rates while in use
Creates a large gap between bolus and infusion
Images
Product Requirements
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No Ferrous Metals can be exposed
Must supply a flow rate between .25 mL/s and 5 mL/s
Control with ease
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Change infusion flow rates
Computer software
Maintain sterility
Move on to infusion immediately after bolus
Decrease waste of Gadolinium and Saline
Reliability
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2-3 protocols per day
Daily Usage
Proposed Design
Finger Pump
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Fingers oscillate to transport fluids
Operated by a camshaft or solenoid
Easy to keep sterile
Gear Pump
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Simple mechanism
Gears rotate to
transport fluids
Difficult to maintain
sterility
Peristaltic Pump
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Motor rotates
segments that move
fluids
Creates a vacuum
Easy to keep sterile
Proved itself in
medical applications
Motor
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Bell-type armature motor
Non-ferrous
Symmetrically balanced permanent magnet
Speed linearly proportional to voltage
Problems and Future Considerations
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Magnetic shielding for servo motors
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MuShield
Calculations for desired operation
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Torque needed by motor
Diameter of tubing
Properties of the two fluids
Alternatives
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Motor Driven Pump
Often contains metal material
 Cannot be next to scanner
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Dielastic Actuators
Malleable capacitors
 Elongates  used to propel gears
 New, not on market
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Our Solution
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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
Saline
Contrast
Pumps
Y Connector
To Patient
The Pump…
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Peristaltic Pump
Aluminum or titanium
rollers
Rollers propelled by gears
Gears driven by pressure
acting as motor
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Air, Water, Nitrogen, Oxygen,
CO2
Broader View:
Pressure
Pressure
Saline Line
Contrast Line
Pressure
Pressure
Rollers
Gears to
control roller
spin rate
To Patient
Problems
MRI interference
 Running cables from control room
 Safety of propelling gears
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Advantages
Saving money
 Set-up time reduced
 Preparation minimal
 Allows bolus & infusion to take place
during same scan
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Design Option 1
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Use a force driven
syringe pump
Force source
possibilities
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Gravity, gas under
pressure, elastic
materials, liquid under
pressure, or dielastic
actuators
Design Option 2
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Peristaltic pump
powered by a flywheel
and gear system
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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
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System applying force to bag reservoirs.
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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
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http://www.maztravel.com/enrique/tour3.html
http://www.animatedsoftware.com/pumpglos/pu
mpglos.htm
www.medrad.com
www.edmond/wheelchair.com/i_v__stands.htm