Patent ID: 6224554
Filing Date: 2001-05-01
Classification: A61B

Abstract:
A method for measuring ambient pressure at a region of interest in a fluid-filled body cavity or vessel comprising the steps of:(a) introducing into said cavity or vessel a composition of gas-containing microbubbles, said microbubbles having a predetermined fragility threshold, said fragility threshold correlating the disintegration response of said microbubbles to a combination of fluid and applied acoustic pressure, said acoustic pressure being applied from an ultrasonic energy producing source and said composition having predetermined acoustic response properties correlating to ambient pressure of a surrounding fluid;(b) applying an ultrasonic signal at said region of interest within said cavity or vessel at a power level sufficient to cause acoustic pressure to disintegrate a microbubble population, said power level being above or equal to said predetermined fragility threshold;(c) detecting the returned acoustic signals backscattered from the population of disintegrating and intact microbubbles remaining at said region of interest;(d) correlating said returned acoustic signals to said predetermined acoustic response properties of said composition to determine said ambient pressure at said region of interest;(e) repeating steps (a)-(b).