Medical Device Daily

GE Healthcare (Waukesha, Wisconsin) reported winning FDA clearance for its new wide bore computed tomography (CT) system, which consists of two configurations and, according to the company, is the “most powerful 16-slice wide bore CT.”

One configuration, the LightSpeed Xtra, is designed to enable the obese or morbidly obese (meaning those more than 100 pounds overweight) to be able to undergo the procedure, which many now are prohibited from doing because they are too big to fit into the system. It is also geared to interventional use and trauma cases.

The other configuration, the LightSpeed RT 16, is a CT scanner which is designed to enable advanced imaging for radiation therapy planning, which has increasingly become the norm in radiation therapy prior to administering treatment.

“We had a lot of interest from a number of our radiology customers around using the wide bore system that we had for obese patients for interventional purposes,” Kelly Piacsek, global product manager for radiation oncology at GE Healthcare, told Medical Device Daily. “But we did not feel like the power and the speed of that system was capable of supporting those applications, and that's why we went to this new system.”

According to Piacsek, 16 slices in a radiology environment is “more applicable than four [slices],” which are individual images.

Whereas the standard gantry opening, or large circle through which the body fits on a board, is 70 cm, the LightSpeed RT16 offers “better patient positioning” with an 80 cm gantry opening for radiation therapy planning.

“GE was the first to market with multi-slice bore technology for radiation therapy, and now we have the most versatile wide bore system available,” said Gene Saragnese, vice president and general manager of the company's global Molecular Imaging and CT business.

Piacsek said that while all of the major vendors offer a multislice wide bore scanner, GE is the only one which offers, as part of its standard scanner configuration, “high power,” which is a 100k power generator. The LightSpeed's performance X-ray tube “delivers up to 800 mA,” she said.

“The reason that's important is because we have larger patients, and if you don't have enough tube power, you can't necessarily get the diagnostic image quality that you're accustomed to seeing with smaller patients,” she said.

GE said that according to the American Obesity Association (Washington), more than 20% of the U.S. population is obese, with 6 million Americans morbidly obese.

GE said its VT 2000 table has been “optimized for accuracy of table movement when imaging large patients.”

“Actually, we find that most of our customers claim that they've had to turn away a number of patients,” she said. “Even if that number is small, the question is really, 'Are we denying care to a subset of our population that really needs it?' And when you think about coronary artery disease and other diseases that are very common in obese populations, the one thing that they could truly benefit from is CT.”

In other words, she said, even if only a few are being turned away, “those are the people that really need the care, [and] we need to make sure that we're providing a technology that covers the whole population.”

As for the LightSpeed RT16, it is needed because, increasingly, radiation therapy has evolved and now often includes such things as proton therapy or Gamma knife or other “really high precision treatments,” she said, making the need for 16-slice – which essentially is designed to provide more and better images of the targeted tumor or lesion – more necessary.

“Up until this point, four-slice or single slice has been relatively adequate for radiation oncology,” she said. “But as the therapy evolves, the imaging technology has really needed to follow that. So, that's a big part of why we went down this technology pathway, as well.”

Both of the new LightSpeed configurations are equipped with 3D Dose Modulation, which in the standard 70 cm gantry has previously resulted in “up to a 30% dose reduction” in radiation, because of the precision of the imaging.

“With radiation and CT, one of the things we want to do is keep the radiation exposure as low as possible, and the 3D Dose Modulation allows us to survey the patient before they're actually scanned to determine how dense and how large they are,” she said.

Then, using “sophisticated algorithms,” the dose can be matched more precisely to the patient.

Through the remainder of 2006, GE said it will set up pilot sites and conduct studies using both LightSpeed RT16 and LightSpeed Xtra. Both configurations are expected to be fully commercially available in early 2007.