Acuson's ART feature clears signal as firm positions for market upturn

Acuson and its founder/CEO Samuel H. Maslak are hitting the roadthis month to tout technology in a manner reminiscent of the ultrasoundvendor's initial launch of its high-end 128 scanner a decade ago.Similarities between 1983 and 1993 abound, not only in the launchlogistics for Acuson's Acoustic Response Technology (ART) signalprocessing upgrade, but also in the general interplay betweenthe market position of ultrasound, its growing clinical effectivenessand trends in the general health care delivery system, Maslaktold SCAN.

While health care costs will be contained further in the U.S.and abroad over the coming years, cost pressures were also evidentin 1983 with the implementation of reimbursement according todiagnosis-related groups within the Medicare system, he noted.Yet Acuson, in its first product launch, created a new upper tierin the market, proving that customers would pay extra for enhancedimage quality and clinical utility despite payment pressure. Ultrasoundis well positioned today to catch the upside of an increasinglycost-sensitive medical imaging market.

"If the new health care cost management programs comingout of Washington place an emphasis on covering more Americansat a lower per capita rate, ultrasound is the logical diagnosticimaging modality to benefit most from that," Maslak said.

Ultrasound will benefit from changes in the health care deliverysystem not by decreasing the cost--and quality--of equipment butby catering to the need of providers to balance cost and performancein a more competitive environment, he said.

"There isn't new value in reducing the cost and qualityof equipment. There is no innovation on the part of hospitalsthat would allow them to be more cost-effective providers,"Maslak said. "Taking the most expensive ultrasound (scanners),the equipment is already less expensive than the technician whouses the equipment. You don't have much leverage by reducing thecost, but you do have a lot to lose."

Following two years of slowing market growth after the late1980s boom, ultrasound appears poised on the brink of anotherperiod of rapid performance improvements, he said. With ultrasoundremaining more price-effective than most imaging modalities, performanceimprovements are likely to expand the use of ultrasound in newand existing applications.

"The next five years are going to show more dramatic advancesin (ultrasound) imaging capabilities and image quality than hasoccurred in the last five years," he said. "I am moreexcited about the prospects of ultrasound now than I have beenat any time in the past five or six years. Ultrasound is goingto emerge as the primary diagnostic imaging modality used by physicians."

One significant difference from a decade ago, however, is thatseveral of Acuson's competitors are also investing heavily inresearch and development. Of primary concern to Acuson in defendingits position atop the U.S. radiology ultrasound market is encroachmentby ATL. That vendor, which introduced its own signal processingupgrade last month (SCAN 4/21/93), appears to be taking sharefrom Acuson in a tight U.S. market.

As cost concerns increase, users will increasingly seek newvalue from the technology, Maslak said. Technological value canbe defined in terms of three criteria:

• increased diagnostic confidence leading to better patientcare;

• improvements permitting existing procedures to be performedmore efficiently; and

• changes that allow clinical customers to improve thefunction of their practices.

Acuson's Aegis image handling system (SCAN 10/21/92), whichwill begin commercial shipments this summer, is aimed both atimage improvements and greater efficiency. The vendor has alsosought to expand clinical flexibility by providing various configurationsof the basic 128-channel XP platform, including the mid-tier XP4 color system (SCAN 4/21/93) and the XP SP, a special procedurescardiac unit with intraoperative capability, introduced last month.

ART will be the main feature of seminars set up by Acuson in10 U.S. cities and a half-dozen locations in Europe and Asia.The technology focuses on improving image quality with a relativelyinexpensive upgrade option. Speed of exams can also rise withgreater clarity of image and ease of use of transducers, Maslaksaid.

Shipments of ART are expected to commence in the fall.

ART will cost 10% to 20% above existing Acuson system prices,depending on the configuration of features. All systems, includingthe XP 3 and XP 4, can be upgraded to the premium XP 10 with ART.Acuson will offer free upgrades from the black-and-white XP 3to the XP 4 for all users under warrantee or service contract.

"The XP 10 with ART, together with the (standard) XP 10and the XP 4, represent a whole new lineup of products for Acuson,"Maslak said. "They strengthen our focus on new value throughtechnology. We will have three products with different price andperformance points."

The objective of ART is to control variations in the spectrumof frequencies within an individual ultrasound pulse, accordingto Clay Larsen, director of marketing for general imaging. Thesespectrum changes, or tissue bandwidth aberrations, occur as amatter of course when relatively weak ultrasound pulses pass throughthe imperfect signal propagation medium of body tissue.

Tissue bandwidth aberrations include a shifting of the centerfrequency, a change in the bandwidth of frequencies and a distortionin the shape of the ideal frequency distribution. This distributionis plotted as a wide, bell-shaped curve called a Gaussian pulse,he said.

Signal control is performed automatically as the scanner isprogrammed for different procedures. For instance, when frequenciesare changed while using multihertz probes, the ART controls adjustaccordingly to maintain consistency in the signal frequency distribution.

ART adjusts signal-related parameters within the transducers,the transmission and receive electronics and in postacquisitionsignal processing. During the pretransmission steps, the ultrasoundwaves are altered in anticipation of subsequent distortions, sothe final frequency spectrum better resembles the theoreticalideal.

"Engineers used to think they would have to live with these(tissue bandwidth aberration) effects," Larsen said. "Nowwe have developed precise ways (of tuning) both electronics andtransducer processes to manage the shape of the pulse even afterit has gone through tissue at depth."

ART processing increases the amount of information that canbe extracted from the ultrasound pulse, thus enhancing borderdefinition, tissue texture and contrast resolution, Acuson maintains.Improved sensitivity at depth is found in pulsed and color-flowDoppler performance as well as gray-scale images.

Acuson does not claim to tune the signal according to the typeof tissue it is penetrating. Ultrasound technology has not progressedto the point where tissue signal effects can be determined onan organ-specific basis.

"We are not making a priori assumptions of how one typeof tissue will respond versus another," Larsen said.

However, since the parameters of the scanner are set differentlywhen imaging particular body objects, ART will also vary accordingly.