TRANSCUTANEOUS ELECTROMAGNETIC FLOWMETRY: VOLTAGE DISTRIBUTION IN A BLOOD VESSEL - LIMB SEGMENT CYLINDRICAL MODEL
Authors not listed
Researchers developed a cylindrical model to estimate popliteal artery flow from skin voltages measured during brief magnetic field exposure.
Plain English Summary
The method uses a concentric three-media cylindrical model to estimate popliteal artery flow from skin surface voltages. Subjects lie supine with the leg in a 16 cm magnetic pole gap while EEG electrodes detect voltages under 100 µV for less than two minutes. In an example with 100 cc/min flow, the maximum skin voltage was 5 µV while the maximum vessel voltage reached 86 µV. Calculated current densities were well below levels known to excite membranes or damage blood, and subjects reported no sensation.
Why This Matters
The voltage at each point depends on radial and angular position, vessel and segment radii, and electrical conductivities, and is directly proportional to magnetic field and flow rate. A maximum electric field of 0.6 mV/cm and current density of 0.05 pA/cm² occur at the vessel center. Standard ECG electrodes are placed on the lower thigh and connected to an EEG preamplifier. The voltage equations are derived from the generalized Ohm's Law and the Poisson/Laplace equations. The model has been extended to measure brachial and bilateral common carotid flows using conformal transformation and superposition.
Show BibTeX
@article{transcutaneous_electromagnetic_flowmetry_voltage_distribution_in_a_blood_vessel__g5414,
author = {Unknown},
title = {TRANSCUTANEOUS ELECTROMAGNETIC FLOWMETRY: VOLTAGE DISTRIBUTION IN A BLOOD VESSEL - LIMB SEGMENT CYLINDRICAL MODEL},
year = {n.d.},
}