Diasonics unveils work in breast tissue imaging

Elastography papers presented at AIUM

Ultrasound vendors wounded by sluggish scanner sales are lookingfor a means to kickstart the market. One way is to acceleratedevelopment of new applications for the modality that might sparka rally in equipment purchasing.

One of the most promising potential applications of ultrasoundis to use it for the detection of differences between malignantand benign breast lesions, thus avoiding unnecessary biopsy. Lastmonth Diasonics Ultrasound became the latest vendor to unveilits technique for tapping into what could be a significant newmarket.

Diasonics of Milpitas, CA, is sponsoring research at the Universityof Texas in elastography, a technique that uses ultrasound andtissue compression to visualize the differences between normaland abnormal tissue. University of Texas researchers presentedtwo papers at last month's American Institute of Ultrasound inMedicine meeting describing their work on the technique.

Elastography involves measuring the elasticity of tissue beforeand after breast compression, according to Diasonics presidentand CEO Bruce N. Moore. By comparing changes in the elasticityof tissue under compression, clinicians may be able to determinewhether or not a lesion is malignant or benign.

Clinicians using elastography first conduct a normal ultrasoundscan without breast compression. Compression is then applied andanother image taken. One image is subtracted from the other usingan algorithm in the scanner. The University of Texas researchershave found that malignant lesions react differently than benigncysts when under compression, and these differences in elasticityare detected and measured by the algorithm. The result is displayedas an elastogram.

While the technique uses gray-scale ultrasound, it does notmeasure differences in gray scale, Moore said. Elastography'sability to detect differences in tissue elasticity is enhancedby recent improvements in Diasonics' gray-scale imaging, however.

The University of Texas research is being led by Dr. JonathanOphir. At the AIUM meeting, Ophir presented papers on the acousticaland mechanical properties of elastography images, as well as methodsto improve the signal-to-noise ratio in elastograms.

Diasonics has been sponsoring the research for several yearsand plans to file either a 510(k) or premarket approval application(PMA) with the Food and Drug Administration to commercialize elastography,according to the company.

"The work has been done in terms of proving the validityof the technique," Moore said. "Now we are working onthe commercialization of the technology."

Elastography could be performed using the current architectureof Diasonics scanners, Moore said. Scanners would have to be modifiedwith a compression device to conduct the technique, however. Whilethe initial work on elastography is in breast imaging, the techniquecould have applications in other areas, he said.

Competitor ATL is taking a different approach to breast tissuevisualization. Earlier this year the Bothell, WA, firm filed apremarket approval application (PMA) with the Food and Drug Administrationfor the use of HDI (high-definition imaging) technology to differentiatemalignant from benign masses (SCAN 1/19/94).