Imaging with Multiple Aperture Medical Ultrasound and Synchronization of Add-On Systems

Abstract

The benefits of a multi-aperture ultrasound probe can be achieved with add-on devices. Synchronization and correlation of echoes from multiple transducer elements located in different arrays is essential to the successful processing of multiple aperture imaging. The algorithms disclosed here teach methods to successfully process these signals when the transmission source is coming from another ultrasound system and synchronize the add-on system to the other ultrasound system. Two-dimensional images with different noise components can be constructed from the echoes received by individual transducer elements. The disclosed techniques have broad application in medical imaging and are ideally suited to multi-aperture cardiac imaging using two or more intercostal spaces.

What is claimed is: 
     
         1 . A method of synchronizing an add-on ultrasound system to a host ultrasound system, comprising the steps of:
 transmitting ultrasound pulses from a host ultrasound probe using a host ultrasound processor of the host ultrasound system;   receiving the ultrasound pulses with an add-on ultrasound probe of the add-on ultrasound system; and   synchronizing the add-on ultrasound system to the pulses transmitted from the host ultrasound probe by processing data from a tap that couples the host ultrasound system to the add-on ultrasound system with an add-on ultrasound processor of the add-on ultrasound system.   
     
     
         2 . The method of  claim 1  wherein the receiving step further comprises receiving the ultrasound pulses with a plurality of add-on ultrasound probes of the add-on ultrasound system. 
     
     
         3 . The method of  claim 1  further comprising displaying ultrasound images of tissue from the add-on ultrasound system. 
     
     
         4 . The method of  claim 1  wherein the transmitting step comprises transmitting ultrasound pulses into tissue. 
     
     
         5 . An ultrasound imaging system, comprising:
 a host ultrasound imaging system comprising a host transmit probe configured to transmit ultrasound pulses and a host processor;   an add-on ultrasound imaging system comprising an add-on receive probe configured to receive ultrasound pulses from the host transmit probe and an add-on processor; and   a tap connecting the add-on processor to the host transmit probe, the tap enabling the add-on processor to determine a start time and a direction of the ultrasound pulses transmitted from the host transmit probe.   
     
     
         6 . The system of  claim 5  wherein the add-on processor is configured to process data from the tap to synchronize the add-on ultrasound imaging system to the host ultrasound imaging system. 
     
     
         7 . The system of  claim 5  further comprising a display adapted to display ultrasound images from the add-on processor. 
     
     
         8 . The system of  claim 5  further comprising a second add-on receive probe. 
     
     
         9 . The system of  claim 5  wherein the start time is determined by identifying an interval between amplitude peaks that is substantially larger than a pulse repetition interval. 
     
     
         10 . The system of  claim 5  wherein the start time is determined by identifying a large change in peak amplitudes during successive scan lines. 
     
     
         11 . The system of  claim 5  wherein the start time is determined by identifying when a peak amplitude changes from a low to a high or vice versa.