Inventors:
Larry S. Matthews - Ann Arbor MI
Steven A. Goldstein - Ann Arbor MI
Assignee:
Board of Reagents of the University of Michigan - Ann Arbor MI
International Classification:
A61B 502
Abstract:
This invention provides a means of measurement tissue pressure in muscle compartments and other regions in humans and other animals. An appropriate length, for example, 6 to 12 inches of thin plastic tubing, typically less than 3 mm outside diameters, is prepared as a working part of the tissue pressure transducer. A portion of the plastic tubing including the thin wall section such as a bubble is inserted into the muscle tissue for which pressure measurement is desired to be made. A fluid is circulated through the tubing at a constant flow rate. When the internal pressure of the tubing is greater than the external pressure, the bubble expands and there is no increase in the flow resistance of the system. When the pressure on the outside exceeds the normal system operating pressure, the thin wall section or bubble contracts, resistance to flow increases, and the system pressure increases. This increase in system pressure is directly proportional to tissue pressure.