Optical observation of contrast agent destruction

Fragmentation of an ultrasound contrast agent on the time scale of microseconds provides opportunities for the advancement of microvascular detection, blood flow velocity estimation, and targeted drug delivery. Images captured by high-speed imaging systems show destruction of a microbubble during compression. Peak wall velocity of -700 m/s and peak acceleration of 1.2 x 10(12) m/s(2) is observed for insonation with a peak pressure of -1.1 MPa and a center frequency of 2.4 MHz. Theoretical calculations of wall velocity and acceleration using a modified Rayleigh-Plesset model predict a peak negative wall velocity of -680 m/s and peak acceleration of 2 x 10(12) m/s(2). (C) 2000 American Institute of Physics. [S0003-6951(00)03030-8].