A new high frequency destruction/reperfusion system

In order to improve the resolution of contrast-assisted imaging systems, we have created a high frequency destruction/reperfusion imaging system with a spatial resolution of 160 by 160 μm. The system utilizes a 1 MHz cylindrically focused transducer for destruction and a 25 MHz spherically focused transducer for pulse/echo imaging. Using a new estimation technique, flow constants proportional to absolute flow rate were estimated from B-mode time-intensity curves. The in vitro results indicate a correlation between the actual flow velocity and the estimated rate constant. In vivo images are presented showing blood perfusion in the ciliary processes and iris of the rabbit eye. Potential applications of this system include high-resolution perfusion assessment in small animals.