Acuson debuts harmonic technique at ASE for difficult-to-image patients

Sequoia C256 package will be migrated to other platforms

Ultrasound vendor Acuson last week introduced its version of a new imaging technique that promises to reduce artifacts and improve image quality in difficult-to-image patients. Acuson joins other ultrasound vendors that are exploring the use of harmonic imaging, a method of processing ultrasound echoes that are multiples of the original signal.

Harmonic imaging adds even more information to scanners that are configured to recognize second-harmonic waves, which have traditionally been rejected by ultrasound scanners as noise. With harmonic imaging, scanners can process diagnostic information from wave echoes that are twice the frequency of the original sound wave. This has particular benefit in difficult-to-image patients who require the deeper penetration possible with low-frequency waves. With the higher frequency gained from the second-harmonic wave, clinicians can gain the benefits of a lower frequency echo with the improved image quality garnered from higher frequency echoes. Harmonic imaging also offers the added benefit of reduced image clutter.

At last week's meeting of the American Society of Echocardiography in Orlando, Acuson released Native Tissue Harmonic Imaging for use on its Sequoia C256 echocardiography scanner. The technique, the first step in Acuson's development of a package of harmonic-imaging techniques, adds software programming to Sequoia C256 and uses Acuson's existing 3V2c and 5V2c transducers to image the second-harmonic signal. Sequoia then employs its coherent imageformer to generate the image, using both phase and amplitude data in the ultrasound signal.

"The advantage of Native Tissue Harmonic Imaging is that it clears the clutter away from these tissues and enhances their presentation in the image so that you get a more precise definition of the heart walls," said John Davidson, cardiology marketing manager for Acuson.

Among the difficult-to-image patients likely to benefit from this technique are overweight patients and those who have overlying lung tissue, breast implants, congestive pulmonary disease, narrow rib spaces, or a thick chest wall, according to Acuson.

Clinical evaluations of the technique were performed at the Cleveland Clinic Foundation and the Mayo Clinic in early June. Shipments of the upgrade also began this month. Acuson expects to migrate elements of this technology to other platforms in the Acuson product family, Davidson said.

Native Tissue Harmonic Imaging is priced at $15,000 for a new scanner and $20,000 as an upgrade. The other component of Acuson's harmonic package is contrast-agent imaging, which will be available by mid-1998 and will cost $10,000 for new systems and $15,000 for upgrades, Davidson said.