Cacophony of claims marks commercial introduction of 64-slice scanners

CT vendors delivered on promises made a year earlier with the delivery of 64-slice scanners. As the RSNA show floor opened, each of the four major vendors - Siemens, GE, Philips, and Toshiba - was either shipping these megaslice scanners or planning to begin doing so in early 2005. The offerings, however, were anything but homogeneous. The differences became apparent in each company's presentation of its products and discussion of its competitors.

Claims and comments revolved around the number of slices as well as product status. Several industry execs took issue with the moniker applied to Siemens' Sensation 64, noting that the scanner, which has 32 detector elements, generates 64 slices by waggling the flying focal spot. Siemens shot back that resolution, not detector elements, was the issue and that customers clearly agreed, as the company had installed 45 such systems worldwide including 16 in the U.S., putting it well ahead of its competition.

Toshiba was second as of the start of the meeting, with six systems installed worldwide and a seventh due in January. Philips and GE each had one.

Toshiba's Aquilion 32, GE's LightSpeed Pro 32, Philips' Brilliance 40, and Siemens' Sensation 40 were presented as lower priced alternatives. Philips and Toshiba showcased niche scanners for oncology, while Siemens dotted the landscape with CTs at a variety of price points. Hitachi joined the fray with a quadslice scanner and plans to produce a 16-slice CT later in 2005.

GE Medical Systems

LightSpeed VCT moved to the head of GE's CT commercial portfolio on the heels of clinical tests performed since midyear at its Froedtert Hospital luminary site. General availability was pegged for early 2005.

• LightSpeed VCT with V-Res Detector and Performix Pro tube features a 64-row detector delivering 64 slices for 40-mm coverage with 0.625-mm slices at a rotational speed of 350 msec. Heart scans are completed in four beats.

• LightSpeed Pro32 offers an intermediate alternative for customers seeking premium performance at a lower cost. Static organs are imaged in two seconds. The heart is scanned in 12 seconds. Whole-body scans are done in a breath-hold.

• Xtream, a reconstruction and data storage platform shown at the 2003 RSNA meeting for the LightSpeed Pro16, was demonstrated as a key component of the Pro 32 and VCT. Xtream includes productivity tools such as reconstruction filters that present slices at different thicknesses, offering different levels of noise and image quality, and different reformatting tools. Reconstruction times are boosted from six to 16 frames per second.

• The Realize portfolio of professional services provides marketing, workflow, productivity, and applications training to the buyers of the LightSpeed VCT.

Hitachi Medical Systems America

Once a supplier of CT scanners to U.S. customers under the Philips label, the company lost its footing in North America when Philips began producing its own scanners following the introduction by competitors of multislice CTs. Philips' transition to in-house development was solidified in 2001 with the purchase of Marconi Medical Systems. Hitachi now has returned to the U.S. market with its own line of multislice scanners.

· CXR 4, Hitachi's quadslice scanner, has already entered the U.S. as part of the company's Sceptre P3 PET/CT. It will solo in early 2005, as Hitachi targets imaging centers and other facilities that own its Airis open MR scanners.

· A 16-slice work-in-progress is in development. Commercial release could come as early as mid-2005.

Philips Medical Systems

Philips framed its Brilliance 64 as heir to its superpremium CT offering, talking up early results from tests conducted at Carmel Hospital in Haifa, Israel. By the RSNA meeting, the company had installed eight less powerful, 40-slice systems, which began shipping routinely in early October to luminary sites around the world. Philips also offers a portfolio of six-, 10-, and 16-slice scanners.

• Brilliance 64 complements the 40-slice CT that Philips put into full production two months before the RSNA meeting began. The 64-slice scanner was showcased at the Journées Françaises de Radiologie congress in Paris and is scheduled to begin shipping in mid-2005. It is designed to generate 64 thin slices with 0.6-mm resolution spread over a 40-mm area. By comparison, the 40-slice detector sandwiches 0.6-mm slices between 1.2-mm slices on either end.

• Brilliance CT Private Practice CV (cardiovascular) led Philips' niche offerings. The dedicated cardiac CT system, introduced in late September at the Transcatheter Cardiovascular Therapeutics conference, was customized for use by cardiologists in private practice.

• Brilliance CT Big Bore Oncology, shown weeks earlier at the American Society for Therapeutic Radiology and Oncology meeting, promises better image quality, faster workflow, and shorter exam time. The 16-slice dedicated radiation oncology CT facilitates breast positioning, prostate treatment, respiratory gating studies, integrated absolute marking, and functional CT exams. The CT localization tool allows clinicians to localize the tumor and mark the patient for therapy delivery without leaving the console. The 85-cm bore allows clinicians to measure body mass and better target the location and size of tumors. Its 60-cm field-of-view promises improved geometric accuracy and uniformity when planning treatments.

• Brilliance Workspace 2.0 user environment supports the Philips MSCT portfolio. This latest version of Workspace supports the assessment of lung nodules and emphysema and cardiac CTA. A virtual colonoscopy package features a detailed view, called Filet, which presents the interior colon as a landscape, facilitating interpretations. Included in the upgrade are Philips' proprietary CT Viewer and volume intensity projection rendering.

Siemens Medical Solutions

Siemens' 64-slice CT premiered as the most widely adopted superpremium scanner, with 45 installations worldwide at the time of the RSNA meeting and 100 projected by year's end. Speed 4D technology built into the premium scanners features tube technology that allows 0.37-second gantry rotation and faster cooling, as well as optimized data reconstruction algorithms and automated x-ray dose calculations. The Sensation 64 and its 64-slice sidekick Sensation Cardiac complement the Sensation 16 general-purpose workhorse. The Sensation scanners are joined this year by a 40-slice CT. Leading their supporting cast is a new dual-slice entry-level system, a 20-slice system dedicated to oncology, and a family of Emotion scanners with as many as 16 slices.

• Spirit, a newly developed dual-slice product, is slated for release this spring. The scanner, which produces 1-mm slices, is being positioned as a cost-effective replacement for single-slice scanners, a first purchase, or an additional CT in overworked facilities. It has a gantry aperture of 70 cm and can be configured to operate at rotational speeds of 1 or 0.8 seconds.

• Sensation 40, scheduled for a summer release, generates 40 slices per rotation, achieving isotropic resolution of better than 0.4 mm. The system incorporates many of the same subsystems as the Sensation 64, including a high-performance Straton x-ray tube and z-Sharp flying focal spot, which creates two nearly simultaneous data points per detector element.

• Emotion 16 is the newest and highest end member of the upgradable Emotion family of CTs.

• Sensation 64 utilizes a flying focal spot and 32-row detector to produce 64 slices per rotation. At a standard gantry speed of 370 msec, it can achieve a temporal resolution as short as 94 msec.

• Sensation Cardiac, a dedicated cardiovascular system, comes standard with calcium scoring, vessel view, an Argus heart-function tool, Speed 4D workflow package, and 330-msec rotation. These are options on the general-purpose Sensation 64. At the accelerated speed possible with the dedicated cardiovascular system, the Sensation Cardiac 64 generates 200 slices per second with a temporal resolution as short as 83 msec, which is achieved by mathematically recalculating data obtained during ECG gating.

• Sensation Open, announced in April 2004, is a 20-slice CT with an 82-cm FOV and an 82-cm bore. The system is dedicated to oncology applications.

• Virtual colonography software debuted with polyp-enhanced viewing. PEV is designed as a second-read tool for automated identification of lesions in the colon. It gives a computer-assisted "second pass" over the patient data that promises increased detection accuracy and reduced reading times. Works-in-progress include software designed to process CT data to remove bone, support body perfusion, and allow respiratory gating for radiotherapy planning.

Toshiba America Medical Systems

By the start of the RSNA meeting, Toshiba Medical Systems had installed six 64-slice scanners: four in the U.S., one in Germany, and another in Japan. Aquilion 64 is slated for full production in Q1 2005. The company's 32-slice scanner, already in commercial production, is upgradable to 64 slices with the addition of data channels.

• Aquilion 64 CFX is designed to examine peripheral vessels, identify soft plaque, and measure coronary stenosis. The 64-slice scanner uses the same detector as the Aquilion 32 but includes twice as many data channels, which allows the individual use of all 64 detector rows.

• Aquilion 32 CFX is designed as a cost-effective alternative offering a field upgradable path to 64 slices.

• The 64-row Quantum detector built into the Aquilion 64 and Aquilion 32 supports isotropic scanning and advanced image reconstruction technology, delivering slices with a thickness of either 0.5 mm or 1 mm.

• A work-in-progress 16-slice scanner, the Aquilion LB (large bore), is being developed for oncology applications. The LB offers a 90-cm bore, 85-cm display FOV, and 70-cm acquired FOV. A board positioned on the patient table puts the patients at a 25 upward tilt for radiotherapy simulation.

• SurePlaque, a software capability fresh from FDA clearance, creates curved reconstructions through the vascular 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, designed for use on Aquilion CFX cardiac scanners, calculates total plaque volume over the length of the scan and distinguishes between lipid-rich and fiber-rich plaques. SurePlaque is one of the Sure software options designed to automate complex CT imaging studies.