Acuson made a splash at the American College of Cardiology conferencein Anaheim, CA, last month with the introduction of its works-in-progressDoppler tissue imaging (DTI) technique. While ultrasound vendorshave attempted in the past to eliminate tissue
Acuson made a splash at the American College of Cardiology conferencein Anaheim, CA, last month with the introduction of its works-in-progressDoppler tissue imaging (DTI) technique. While ultrasound vendorshave attempted in the past to eliminate tissue motion artifactsin Doppler color-flow imaging of blood flow through vessels andthe heart, DTI turns the process on its head to focus on tissuemotion. The technique may provide new information by using theold Doppler signals in a different way.
"The problem looking into the heart with ultrasound isthat we don't have a very good technique that shows perfusion.There isn't a good (ultrasound) technique for looking at the viabilityof muscle to recover after infarct. This technique (DTI) hasthe potential to do that," said Dr. George Sutherland, seniorresearch fellow with the British Heart Foundation and a consultantcardiologist for the University of Edinburgh.
Initial clinical studies of DTI have been performed at boththe University of Edinburgh and the University of Michigan inAnn Arbor.
DTI offers the hope that ultrasound technology may accomplishsome of what positron emission tomography can do in determiningwhen myocardium is salvageable after a heart attack--but at aconsiderably lower price.
"This is the first time in cardiology that we have beenable to (judge tissue viability) with ultrasound. It would benice to do it with ultrasound because it is a bedside technique.PET scanners are huge machines we have to take the patient to,"Sutherland said.
The DTI technique seems to have little function outside ofdiagnosing patients with coronary artery disease, but that iswhere improvement is particularly needed in cardiology, he said.
Rather than producing a gray-scale image of the heart, DTIproduces a color-encoded image. Variations in the color of themoving myocardium provide information that may not be detectableif the gray-scale image quality is poor.
DTI is one important result of Acuson's increased expenditureson research and development, said William Varley, vice presidentof marketing.
"Acuson spent $48 million on R&D (in 1992). A largepercentage of that has gone to cardiology development," hesaid.
ART will be offered as an option on all new systems and forfield installation on Acuson's installed base of over 8000 ultrasoundscanners worldwide. Acuson says ART will improve image qualityin a broad range of clinical applications, including abdominal,obstetrical, vascular and small parts imaging.