The Development of the VascuMAP
Clinical arterial waveform analysis,
Non-Invasive
Blood Pressure,
Venous plethysmography, and
CW Doppler flowmeter design.
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Links on this page are PDF files explaining the engineering development of the VascuMAP and VascuDOP medical devices I designed between 1989 and 1996.
The VascuMAP performs both volume-calibrated air-cuff plethysmography as well as non-invasive blood pressures (NIBPs) anywhere on the limbs, fingers, or penis. It displays both the blood pressure as well as a volume-calibrated tracing of the pulse wave sensed by the air cuff.
The VascuDOP is a full-function 5MHz continuous-wave Doppler for calibrated vascular flow detection in arteries and veins.
The company that developed these world-class instruments, Carolina Medical Electronics in King, NC, unfortunately dissolved due to poor management. As the main designer of these instruments, I am making the advances incorporated into them available to future engineers. It is knowledge that should not be lost to posterity.
Here are the links to the VascuMAP files:
Development of the VascuMAP - A 21-page history of how the instrument came about.
Appendix A: VascuMAP Operators Manual
Appendix B: VascuMAP Maintenance Manual
Appendix C: VascuMAP Parts Specifications
Appendix D: Volcal Parts
,
Volcal Photo
Appendix E: VascuMAP Marketing Materials
Appendix F: VascuMAP FDA 510(k) Application
Appendix G: VascuMAP Studies:
1) The VascuMAP in Arterial Disease
2) The VascuMAP vs. The PVR
3) Dog Tail BP with the VascuMAP
4) Air Cuff Compliance Data
The VascuDOP has four outputs:
1) a stereo audio output for headphones (forward channel is on the left, reverse on the right).
2) Red and green LEDs on the front panel. Red shows velocity in the reverse direction, green shows the forward velocity.
3) Forward and reverse flow envelope signals from two calibrated frequency-to-voltage converters.
4) Galvanically-isolated Forward-Reverse or I-Q audio outputs (jumper selected) for connection to a separate computer running FFT display code.
Two VascuDOP boards were also combined into one research instrument - the DoubleDOP. This device was used for research to detect arterial flow transit times and also to detect any vascular debris in the cerebral circulation when surgical clamps are released. Only one transmitter was used to drive both 5-MHz probes in this instrument, because the devices had to be synchronized together to prevent one board interfering with the other. The only DoubleDOP ever made dissapeared into the Vascular Surgery department at Wake Forest Medical Center and was never seen again.
Here are the links to the VascuDOP and DoubleDOP instruments files that have survived the past thirty years:
VascuDOP Original Design: The PlugboardVascuDOP Production Design: The Printed Circuit Board
VascuDOP for the VascuMAP II: The Complete Vascular Instrument
The DoubleDOP: A Doppler for Transit Time Analysis
