Toshiba hatches plan to nurse interest in high-performance MR

Looks to compact high-field scanner, long-term

Toshiba America Medical Systems has yet to participate in the growth that has typified the MR industry over the past several years. Although the company earned a reputation for engineering excellence in midfield scanning with its Opart superconducting system in the mid- to late 1990s, the character of the marketplace has recently favored high-field MR, where Toshiba is weakest. But Toshiba plans to change that.

Company strategists have come up with a two-pronged attack. First, in the near term, the company will emphasize high-performance versions of existing mid- and high-field products. It has enhanced its Excelart 1.5T with more powerful gradients and parallel imaging technology and tricked out its Opart 0.35T system with improved gradients. Second, in the long term, Toshiba will shift from the relatively long bore Excelart to an ultracompact system featuring the same magnet as the one built into Philips' (formerly Marconi's) Infinion 1.5T.

"We see this as having the potential to lead us forward in the high-field market," said Anita Bowler, product manager of the Toshiba America MRI business unit.

For the remainder of this year, an expanded and enhanced Excelart will carry the burden of high-field sales for Toshiba. Two configurations, the AG and XG, will be sold. Members of the new Excelart family introduced at the RSNA meeting are differentiated primarily by gradient strength. Excelart AG has a gradient amplitude of 30 mT/m and a slew rate of 50 T/m/s, while XG has a gradient amplitude of 30 mT/m and a slew rate of 130 T/m/s.

Each can be configured with "spin" technology, which includes Toshiba's proprietary Speeder parallel acquisition technology. The "S" (spin) configuration of both the AG and XG comes with a 16-channel QD receiver coil and promises to triple scanning speed while producing images in any plane.

Meanwhile, Opart will get a big brother, a souped up version called Ultra. This new iteration, shown for the first time at the RSNA meeting, is built around gradients that achieve an amplitude of 25 mT/m and slew rate of 100 T/m/s. This combination supports advanced clinical applications, high-resolution imaging, and fast scanning that the company claims are comparable to those of high-field systems, while retaining Opart's open environment. New imaging techniques available on Ultra include single-shot echo-planar imaging diffusion, TrueSSFP (steady-state fast precession), SuperFASE, and black blood MR angiography.

"Our four-post design gives us the capability to push the gradients to support these applications," Bowler said.

The company's long-term ace in the hole is an ultracompact high-field scanner based on the same magnet that Oxford Magnet Technology of the U.K. provided for Philips' Infinion 1.5T. The magnet first entered the marketplace in the MR portfolio of Marconi Medical Systems. The sale of Marconi Medical to Philips brought Infinion to Philips, where it was positioned initially at the head of Philips' open MR offerings. Philips argued unsuccessfully that patient lines of sight qualified the cylindrical system as an "open" product. The company has since abandoned that idea, describing the Infinion as being in a class by itself. If Toshiba has its way, however, this classification will be short-lived.

A Toshiba beta unit incorporating Oxford's ultracompact magnet is scheduled for clinical tests in July 2003. Commercial launch is set for the 2003 RSNA show.

Although the magnet will have exactly the same dimensions as the one in Philips' Infinion 1.5T, Toshiba plans to position the new product as the industry's most compact MR scanner. The rationale is that the new product's cowling will be swept back to create the smallest footprint of any general-purpose high-field MR scanner on the market, according to Bowler.

But Toshiba still has a lot of work to do. At the RSNA meeting, the magnet bore was shown by itself, because engineers had not yet finished designing its patient table. The mock-up sans table was shown, because Toshiba wanted to make a statement.

"We want customers to understand that we are in the 1.5T market to stay," Bowler said. "We are looking into a new design, and we think it will help make us successful."