One of the longest awaited events in radiological history will happen Oct. 24, when Philips Medical Systems unveils its Panorama 1.0T open MR scanner at a Las Vegas outpatient clinic owned by Nevada Imaging Centers.
It will not be the first truly high-field MR system to enter clinical service. That honor belongs to Siemens Medical Solutions, which has installed three 1T Rhapsody systems at sites in the U.S. The Philips scanner has a special distinction, however. It is the only 1T open MR designed for mass production.
Routine deliveries of Philips' Panorama 1.0T are scheduled to begin in 2005, more than five years after the industry first promised such a product. It will be worth the wait, according to Jacques Coumans, Philips vice president of MR global marketing. He predicted the scanner will produce images as good as or better than those achieved at 1.5T at comparable speed, while offering the patient benefits of an open design.
Philips will have to make good on all these claims, if its new product is to succeed. Panorama 1.0T will carry a hefty price tag.
"We will position the 1T open under the 3T (in price) but above the 1.5T, because we feel the value proposition warrants such a price positioning all around the world," Coumans said. "With this product you do not have to worry about the issue of claustrophobia. You have an incredibly large field-of-view, an unexpected boon of fewer artifacts than at 3T or 1.5T, and optimal T1 contrast, which for almost all anatomies provides higher contrast-to-noise ratio."
The actively shielded vertical field superconducting magnet operates on the same platform as the company's cylindrical Achieva. It relies on specially designed coils, however. With these coils, the Panorama 1.0T offers image quality comparable to those of a 1.5T scanner, according to Coumans.
"We have proof of images coming off the unit that are matching the 1.5T cylindrical systems coming out of our factories and those of our competitors," he said. "We have seen that in all anatomical areas."
Scan speed is comparable to what can be achieved with conventional 1.5T systems, he said.
"It has to do with the coils we have made for the vertical field," Coumans said. "They are much more efficient than those for the traditional horizontal cylindrical field systems."
Purchasers of the new system may receive another benefit. Preliminary tests done by Philips indicate that the Panorama 1.0T produces fewer artifacts than 1.5T systems when running cardiac protocols. These apply to the heart and coronaries.
"In the past, neither we nor our competitors had really focused on optimizing cardiac protocols at 1T," he said. "We had all been focusing on 1.5T and even 3T. We are now seeing that the Panorama 1.0T has something more to offer that we ourselves were very surprised about."
Getting to this point has been a roller coaster of expectations and disappointments. Philips announced its intention to build a 1T open scanner at the 2000 RSNA meeting, one year after Siemens unveiled a work-in-progress 1T open scanner. Both companies were responding to GE's release in 1999 of the Signa OpenSpeed, a 0.7T open MR positioned as a high-field scanner.
At the RSNA meetings that followed, Philips and Siemens displayed their own 1T open systems with various refinements and renewed promises. Siemens was the first to develop a clinical prototype, installing three Rhapsody scanners at U.S. sites in 2002. All three are still operating.
But the company abandoned the product, choosing instead to go with an ultracompact cylindrical 1.5T scanner with a wide bore. That scanner, the Magnetom Espree, is being promoted as the first in a new class of MR scanner (SCAN 7/30/04).
Siemens chose this alternative at least partly because of difficulties in coming up with a design that could be economically manufactured (SCAN 6/12/02). Earlier this year, the company added the claim that the market had lost interest in high-field open scanners and would not purchase such systems. Coumans dismisses this claim.
"We think there is a market for a high-end open MR system with an image quality that matches 1.5T cylindrical systems and has none of the claustrophobia-related issues or restricted field-of-view that 1.5T systems have," he said. "Our early customer feedback so far proves the point."
Philips designed the magnet, which is being supplied by its partner Intermagnetics General, to contain the 5-gauss line to an area typically associated with 1.5T cylindrical units. This overcomes the siting problems that had been an issue with earlier 1T open designs, according to Coumans. The company also reengineered the magnet and gradient system to reduce costs, which had been prohibitively high.
Panorama 1.0T will work in concert with two dockable tables, allowing one patient to be moved into and out of the magnet while a second is being prepared. This configuration is designed primarily for high-throughput sites but is also amenable to interventional suites.
"We are looking with a few customers into the option of using the 1T open for neurosurgical and catheter interventions," Coumans said. "But those are research projects and we do not intend to bring out the interventional version for the next 12 to 18 months."