Imperium targets artifacts with new ultrasound system

January 19, 2000

Ultrasound device manufacturers consistently seek to reduce artifacts that compromise image quality, as well as to develop smaller, less expensive devices. A private Rockville, MD-based firm, Imperium, hopes to enter the market with a product it believes

Ultrasound device manufacturers consistently seek to reduce artifacts that compromise image quality, as well as to develop smaller, less expensive devices. A private Rockville, MD-based firm, Imperium, hopes to enter the market with a product it believes will address these issues for extremity imaging using optical technology concepts and an ultrasound method it believes to be unique in the industry.

Imperium’s Acoustocam employs a probe encasing a lens about two inches in diameter, which is placed on the skin and focuses returning ultrasound beams onto the unit’s sensor, a semiconductor chip with a 2-D array of 128 x 128 elements. The sensor differs from a typical transducer in that it is used only as a receiver for the ultrasound beams, not as a source. It produces images at 30 frames per second with resolution of 100 to 200 microns. Acoustocam’s ultrasound transmission source can be either built-in or external to the unit. The device includes software that processes the image and displays it as standard video output.

Acoustocam’s lens technology allows it to produce high-resolution images without speckle, according to Bob Lasser, vice president of Imperium. Traditional ultrasound transducers consist of a series of elements, hardwired in place, that electronically move the beam back and forth across the tissue. With this sweeping motion, an ultrasound device gathers data, which is then corrected for artifacts by a computer program. When placed against the tissue to be imaged, Acoustocam’s probe focuses information generated by the ultrasound wave before it gets to the receiver array, thereby producing better quality images, according to Lasser.

“We use ultrasound like a floodlight, rather than sweeping across tissue. When the waves hit the tissue, they scatter, and then our lens focuses them on our sensor. The sensor focuses the information before it is displayed,” Lasser said. “Our images look like real-time x-ray, and we’re getting high-resolution pictures of tendons in the hand and breast cysts, as well as wrist and ankle images.”

Since Acoustocam’s ultrasound transmission source can be either built-in to the camera or used externally, one of the device’s particular features is its ability to perform what Imperium calls “through transmission ultrasound imaging,” in which the ultrasound wave source is placed on one side of the item to be imaged, while the probe/sensor unit is placed on the other side to collect the data. This kind of imaging expands ultrasound’s potential beyond its traditional applications, Lasser said. The company believes Acoustocam could be used for breast biopsy guidance, breast cyst, musculoskeletal, and ob/gyn imaging, and breast, prostate, and testicular cancer imaging. Other future applications could include assessing the tendons and vessels of the hand, wrist, and foot, making it a low-cost way to evaluate tendons of extremities after trauma, according to Dr. Matthew Freedman, clinical director of Georgetown University Medical Center’s division of imaging sciences in Washington, DC, at which Imperium has installed Acoustocam for clinical research use.

The company builds its own components from off-the-shelf materials, which allows it to produce Acoustocam at a low cost: Imperium expects to sell the device for $60,000 or less. And without the processing electronics necessary in a typical ultrasound machine, the device weighs only a few pounds, Lasser said.

Imperium was established eight years ago by Marvin Lasser, former chief scientist for the U.S. Army. Since then, the company has been developing its ultrasound device for industrial markets, and is currently under contract to build a hand-held version of Acoustocam for the U.S. Navy, to be used to inspect aircraft for corrosion. Imperium hopes to sell Acoustocam to OEMs, rather than competing directly in the ultrasound market, Lasser said. The company will rely on these future OEM partners for help with applying for regulatory approval for Acoustocam, depending on the application for which the OEM chooses to use the device. Imperium has placed two of its devices for research purposes: one at Georgetown and another at Overlook Hospital in Summit, NJ.