Diagnostics & Imaging Week

About 62 feet below the ocean near Key Largo, Florida, a team of astronauts from the National Aeronautics and Space Administration (NASA; Houston) and the Canadian Space Agency (Longueuil, Quebec) – called “aquanauts” – will put SonoSite’s (Bothell, Washington) MicroMaxx system to the test.

Can the crew members, most without medical backgrounds, learn to interpret diagnostic images generated on the company’s hand-carried ultrasound system, and via telemonitoring, repair a musculoskeletal injury? And can the MicroMaxx withstand the rugged extreme conditions aboard the underwater laboratory in a remote and harsh environment, designed to mimic what astronauts would experience in space?

The test is scheduled to be conducted in April as part of an 18-day experiment on the ninth mission of NASA Extreme Environment Mission Operations (NEEMO 9), designed to demonstrate and evaluate diagnostic and therapeutic technologies in performing remote surgery.

“I would expect [the MicroMaxx] is going to perform very, very well,” Drew D’Aguilar, general manager of SonoSite Canada (Markham, Ontario), told Diagnostics & Imaging Week.

D’Aguilar’s prediction is based on the performance of an earlier-generation ultrasound system – SonoSite’s Titan – that was used on a previous NEEMO mission.

“On NEEMO 7 in 2004, our hand-carried Titan system performed excellently when it was used to evaluate the abdomen for gallstones, kidney stones and blunt trauma to the chest,” D’Aguilar said. “We are proud and delighted that MicroMaxx has been selected for NEEMO 9, and that SonoSite continues to participate in this program.”

MicroMaxx, Sonosite’s top-end ultrasound product launched for worldwide sales last spring, provides “a higher level of ultrasound, gives better image quality and better color sensitivity” compared to the second-generation Titan system, D’Aguilar said.

Each aquanaut will use the notebook-sized MicroMaxx to perform a diagnostic ultrasound of an injured knee prosthetic under the direction of radiologists and surgeons at the Center for Minimal Access Surgery (CMAS) at McMaster University (Hamilton, Ontario).

After the medical experts in Ontario review the images, sent via satellite from the MicroMaxx aboard the 82-ton Aquarius submarine, they will remotely diagnose the injury and direct the aquanauts to deliver the appropriate treatment. The aquanauts will then be telementored to perform either a simulated arthroscopy of the knee or an external fixation for dislocation.

“In zero gravity, astronauts can suffer severe joint trauma that would require a fellow crew member to identify and treat an injury,” said Julian Dobranowski, MD, chief of Diagnostic Imaging at St. Joseph’s Healthcare (Hamilton), where CMAS is located. “They need systems that can perform under extreme conditions and be deployed quickly in a very tight space. We selected MicroMaxx for this experiment because of its small size, its excellent imaging capabilities, ease of use, and ruggedness.”

A key point of the experiment, according to D’Aguilar, is that the aquanauts who will be using the ultrasound equipment are not trained ultrasonographers, and he said that was another strength of SonoSite’s system. “Our systems are very easy to use, so they’re easy to teach to people.”

What makes the MicroMaxx better than the Titan for the musculoskeletal application on NEEMO 9 is high-performance features such as a 13-6 MHz high-frequency linear array transducer, designed to provide high resolution of superficial structures.

This is “an ordinary feature of a traditional big system, but on a system of this size, that is a very high-end feature,” D’Aguilar said. “It puts the MicroMaxx closer to the capabilities of the very large, expensive [ultrasound] systems.”

Weighing less than 8 pounds and built to withstand the rigors of mobile use, the rugged MicroMaxx system can run on battery power for up to four hours, boots up in seconds and can be carried by hand, enabling clinicians to immediately deliver care whenever, and wherever, it is needed.

According to NASA, long-distance healthcare, like the telemonitoring and remote surgery tested on NEEMO, could be keys to maintaining the wellness of astronauts and responding to medical emergencies during space missions.

D’Aguilar noted that, in space, ultrasound is a superior diagnostic method to X-ray. “First of all, [hand-carried ultrasound] is smaller, very portable, very easy to use and doesn’t have the X-ray dose. Ultrasound is not invasive and X-rays are,” he said, adding: “In space, X-ray is difficult to manage. You don’t want X-rays banging around inside, because X-rays just sort of keep going.”

Other medical device companies with technology to be tested on the NEEMO 9 mission include MD Robotics (Brampton, Ontario), Stryker (Kalamazoo, Michigan) and GE Canada (Mississauga, Ontario). “Splash-down” is scheduled for April 3, 2006.

SonoSite, which began as a division of ATL Ultrasound, now part of Philips Medical Systems, was spun off as a public company in 1998 to create hand-carried ultrasound devices that could be used at the point of patient care.