Leg%20Compression%20Device%20to%20Assist%20in%20Ultrasound%20Testing%20for%20Deep%20Vein%20Thrombosis

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Leg Compression Device to Assist in Ultrasound
Testing for Deep Vein Thrombosis

• Design Team Mark Rawls and Jordan Winston
• Advisors Dr. Raul Guzman and Dr. Paul King

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What is Deep Vein Thrombosis?

• Deep vein thrombosis (DVT) refers to the
  formation of a thrombus (blood clot) within a
  deep vein, commonly in the thigh or calf.
• Symptoms include fever, rapid heart rate, pain
  and swelling in the area
• If not diagnosed and treated, a pulmonary
  embolism can result which can be life threatening

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Problem Formulation

• Technicians attempting to perform the venous
  duplex test for Deep Vein Thrombosis must
  position an ultrasound transducer, manipulate an
  ultrasound console and squeeze the patients leg.
  Therefore, the technician has more tasks to
  perform than available hands.

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Current Testing Process
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Potential Solution Directions

• Innovations Workbench was used to develop
  potential solutions
• Affixation of Transducer to Leg
• Relocation of Ultrasound controls
• Device to Compress Leg

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Effective Solution Direction

• Fixing a transducer to the leg is not feasible
  due to the amount of shifting and compensating
  that is required during the test
• Relocating the ultrasound controls to the
  transducer is not feasible due to the immense
  cost involved in re-designing the common
  ultrasound machine
• Designing a device to compress the leg is the
  most feasible option in both cost and practicality

Courtesy http//www.hku.hk/surgery/vdc/vdc_diagn
ostics.htmDuplex
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Leg Compression Device Demands/Desires

• Demands
• Adjustable Size
• Attachment at Variable Locations
• Foot Control
• Safety Concerns
• Rapid Squeeze/Release
• Durability
• Desires
• Easy attachment
• Easy Detachment
• Variable Pressure
• Inexpensive Assembly

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Potential Design Solutions/Evolution
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Design Comparison
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Final Design Selection 2
Maximum applied force can be set on the foot
pedal through calibration bolt Pulse force is
applied at approximately a 31 advantage Pump
attached with hinges to accommodate motion of
arms.
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Device Specifics

• A hydraulic system for the compression device was
  selected for its simplicity and rapid response
• The maximum necessary span of our device was
  found to be 22 cm
• The maximum force of the pinch needed for the
  device is about 20 pounds of force (89 Newtons)
• The device is equipped with a safety pressure
  valve and a calibration bolt to control the
  maximum force applied during compression

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Market Potential
Market Potential

• 600,000 patients per year are hospitalized for
  DVT in North America
• Approximately 6000 registered hospitals in the
  U.S.
• Initial market for the device will be about 3,000
  units
• Each unit could be sold for around 333,
  corresponding to 1,000,000 in initial income
• Subtracting 500,000 for patent protection,
  regulatory approval, manufacturing costs, and
  marketing leaves an initial profit of 500,000
• In the future, with approximately 10 replacement
  annually, and costs decreasing to 25 of income,
  the device could generate an additional 75,000
  per annum in profit

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Ideas for Further Innovation

• Slotted arms on body of compression device
• Make arm moveable about pivot point (like an
  expandable wrench)
• Telescoping force pump at top of device for
  extended range of motion/compression

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Design Timeline