Toshiba prepares one-two punch in multislice CT

November 5, 2004

Toshiba's strength in CT is an outgrowth of its development of sensor technologies in key modalities. Efforts in CT have produced a 64-slice detector, which will be showcased at the RSNA meeting as part of a continuum of engineering that already extends to a 256-slice detector prototype. The company will display the prototype as evidence of its technological prowess.


CT angiograms of the brain indicate the power of Toshiba's Aquilion 32. (Provided by Toshiba America Medical Systems)Toshiba's strength in CT is an outgrowth of its development of sensor technologies in key modalities. Efforts in CT have produced a 64-slice detector, which will be showcased at the RSNA meeting as part of a continuum of engineering that already extends to a 256-slice detector prototype. The company will display the prototype as evidence of its technological prowess.While detector technology is Toshiba's core competence, it is also the means for implementing a broader strategy of upgradability. That is the message Doug Ryan, Toshiba America's CT business unit director, wants to convey at the RSNA meeting."Our focus this year will be on the Aquilion family, not just one key product," he said.The company will promote the Aquilion 32 as a stepping-stone to the Aquilion 64. The major difference between the two is the number of data channels leading to the detector rows, as each is designed around the 64-row Quantum detector. The 32-slice scanner, which will be in production by year-end, can be field-upgraded later to the 64-slice version with the addition of software and data acquisition boards, Ryan said."We are sending a message to our customers to take the 32 today, develop their cardiac applications, and when they see CPT codes and reimbursement kick in, probably in 2006, upgrade to 64-slice technology," he said.The Quantum Detector, the common thread that ties these systems together, has 64 individual 0.5-mm elements. Field-upgrading 32-slice versions to 64, therefore, should be relatively easy: Just add the extra channels.Toshiba is already laying the groundwork for the development of advanced applications suited to a 64-slice detector, especially those that address cardiovascular issues. An Aquilion 64 CFX optimized for vascular study has been operating at Fujita Health University in Japan since March. Luminaries in the U.S. are preparing to work with similarly equipped systems. Johns Hopkins began operating a 32-slice Aquilion earlier this year and could upgrade to 64 next year. Beth Israel Deaconess Medical Center was scheduled to take delivery of a 32-slice scanner in October with the intent of upgrading to 64 slices later on.As these sites upgrade from 32 to 64, they will chart a path for other Toshiba customers to do the same. This upgradability makes a persuasive argument for buying an Aquilion 32 CFX, according to Koji Honjoh, group manager of Toshiba's international business group for CT. The new system offers 1.8 meters of scan coverage, achieving a longitudinal resolution between 0.35 mm and 0.4 mm, even in body regions prone to streak artifacts."We are convinced that Aquilion 32 is far superior to the current 16 in clinical value, not only for cardiac but for radiology procedures," Honjoh said.Clinical testing of the 32-slice version has produced an artifact-free lumbar myelogram of a patient with double fusion rods in the spine. A nine-second scan of a cirrhotic liver shows the portal venous phase in extraordinary detail. Scans of abdominal aortic aneurysms demonstrate fine vessels leading to the kidneys. Cardiovascular applications may benefit most from the 32- and 64-slice Aquilions. Luminaries are hopeful that coronary CT angiography will reveal relevant obstructions in the coronaries and bypass grafts, as well as areas of necrosis and hibernation in the heart. Combined with stress, which would likely be induced pharmacologically, advanced Aquilion technologies might provide enough data to formulate a comprehensive assessment of a patient's cardiovascular health.The advantage of a 64-slice configuration is seen primarily in its time saving. An Aquilion 16-slice scan of the heart takes 25 seconds, and a 32-slice scan cuts the time to about 15 seconds, according to Honjoh. Going to 64 slices decreases scan time to the single digits. "This reduces the chance of running into irregularities or variations in heart rate," he said. "That is why we have decided to go to 64." Persuading prospective customers to jump from 16 slices to 32 and later to 64 is essential to Toshiba's strategy for improving its position in the ranks of CT providers in the lucrative U.S. marketplace. Just adding slices, however, will not be sufficient. Clinical utility is key to the adoption of more advanced technologies.Toshiba's answer is its suite of Sure algorithms, which handle tedious and difficult tasks. SureCardio turns CT data into motionless volumetric coronary angiograms. In one patient, this algorithm demonstrated not only two implanted stents but soft plaque that had begun to creep into one of them."The aim is to make cardiac CT easy," said Jeff Hall, Toshiba CT application development specialist.At the RSNA meeting, the company will highlight SurePlaque, which Ryan hopes will soon be ready for commercial release. The algorithm, developed in collaboration with luminaries at Johns Hopkins, creates curved reconstructions through the region of interest, segments the vessel, then draws the outer wall of the artery and quantifies the plaque over a defined length of the vessel. The algorithm calculates total plaque volume over the length of the scan and distinguishes between lipid-rich and fiber-rich plaques."It is certainly one of the pioneering technologies from Toshiba in that it not only quantifies plaque but assigns a clinical value to it," Ryan said.SureConnect is also likely to be in the Toshiba spotlight at the RSNA meeting. This member of the family focuses on workflow and IT compliance with the Integrating the Healthcare Enterprise initiative.The Sure algorithms are designed to be forward-compatible through Toshiba's planned slice growth from 16 to 32 to 64. They will remain so for the 256-slice scanner that Toshiba is already testing. The prototype has limited resolution, but that is expected to change. "The detector is there, but the gantry is not ready yet for release. We're still waiting on the computer system to catch up," Ryan said.