MR vendors repackage and reorganize existing products

This year¹s RSNA meeting held few surprises in MR, as manufacturers updated prospective customers on progress in equipment development but unveiled no new systems. Despite more than two years of talk, the commercial release of 1T open scanners remains elusive, as the promoters of this technology continue to clinically validate their equipment.

Siemens¹ Rhapsody is operating at only one clinical site, in Germany, although a second unit is scheduled for U.S. installation by February. Philips¹ Panorama 1T is running, but only at Philips. The commercial absence of these systems has allowed GE and Hitachi to pitch their 0.7T scanners as the market¹s only higher field open products.

The 3T segment was noteworthy at the RSNA exhibit more for the effects of consolidation than for technological progress, as the first fatality of Philips¹ acquisition of Marconi surfaced. Philips executives announced their decision to continue developing their Intera 3T whole-body product and to drop Marconi¹s version. Intera 3T is still pending FDA clearance. Siemens¹ whole-body Trio has passed FDA review, but is not yet in production. GE executives leaped on that fact, pointing out that their 3T whole-body system had been commercially available for much of 2001.

For the most part, vendors seemed content with the status quo, offering iterative upgrades, shuffling products, or naming works in progress. Standouts included GE¹s repackaging of the 1.5 and 1T MR/i as Infinity, a name change based largely on new software; Philips¹ decision to classify the Infinion 1.5T scanner as ³open,² despite its conventional, albeit ultracompact, cylindrical bore; and the rash of names (GE¹s ASSET, Siemens¹ iPAT, Toshiba¹s SPEEDER) coined to describe proprietary versions of sensitivity encoding. Philips first popularized the technique as SENSE. True to form for this RSNA meeting, shipping dates for the new sensitivity encoding technologies range from mid- to late 2002.

Aurora Imaging Technologies

The only maker of a dedicated MR mammography scanner, Aurora has focused primarily on demonstrating the clinical validity of its 0.5T system. The scanner, which includes a 64-cm bore and can image patients up to 500 pounds, has been installed at five clinical centers across the U.S.

• Promotional efforts center on the use of MR mammography as a screening device as well as its use in patient assessment for the extent of cancer, presurgical planning for removal of tumors, and evaluation of breast implant integrity.
  
• A work-in-progress MR-compatible biopsy device was featured. Clinical studies of the device are under way at Faulkner Hospital, a 130-bed community teaching facility near Boston.

Esaote/GE Lunar

Esaote has supplied scanners to Lunar since 1993. The relationship continued after GE Medical Systems acquired Lunar in 2000, allowing GE Lunar to sell Esaote-built dedicated extremity scanners in the U.S. while the Italian manufacturer sells them in other world markets. Esaote has also continued supplying Siemens with one of these products (E-Scan), which has been modified slightly to create the Magnetom Jazz.

• C-Scan was unveiled as the successor to Esaote¹s eight-year-old Artoscan extremity system. The new product has the same 0.2T magnet as the Artoscan, but offers a more compact design, a new computer, and updated software. The new scanner integrates DICOM as a standard capability.
  
• E-Scan, an open-style dedicated extremity scanner, features a new flexible ³universal² coil for shoulder and hip imaging.

Fonar

Fueled by civil court judgments and out-of-court settlements with major manufacturers, the company has brought several new scanners into production in recent years, notably its stand-up MRI, called Indomitable. It was among six products the company featured at the meeting.

• Two users of the stand-up scanner presented clinical results at the Fonar booth that highlighted dynamic imaging and the advantages of weight-bearing imaging.

GE Medical Systems

The company has assembled one of the most comprehensive product offerings in the industry, including cylindrical whole-body scanners available at 3, 1.5, and 1T, as well as open systems at 0.35 and 0.7T.

• New in name but old in hardware, the 1.5 and 1T Signa Infinity is identical to its predecessor, the MR/i, except for a software upgrade called Release 9. The software features 15 applications packages, including fluoro-triggered MR angiography, comprehensive cardiovascular imaging, 3D prostate imaging, 3D brain spectroscopy, and ultrafast breath-hold abdominal imaging.
  
• Like other such technologies, ASSET, GE¹s proprietary version of sensitivity encoding, relies on a set of phased-array surface coils and advanced pulse sequences to increase resolution and reduce scan time.
  
• TwinSpeed, although technically an optional configuration within the Infinity product line, was given special attention by GE as the only product of its type to incorporate two gradients. More than 40 systems have been shipped since the product was commercialized after the 2000 RSNA meeting.
  
• GE¹s 3T whole-body scanners began shipping this year. As of the RSNA meeting, three such units were operating at clinical sites and several were in the process of being installed.

Hitachi Medical Systems of America

The company that popularized the open scanner strummed familiar chords at the RSNA meeting, focusing on enhancements to its midfield open products, particularly the Airis II, and its most recent release, the higher field open Altaire.

• Routine clinical images highlighted the 0.7T Altaire, introduced at the 2000 RSNA meeting. These images establish a baseline for clinical performance, validating claims about high-field imaging on an open magnet, according to the company.
  
• Multi-array coil technology in a new cervical-thoracic-lumbar coil and a shoulder coil was shown for the Altaire.
  
• A neurovascular coil and a peripheral vascular coil that allows runoff studies are in the works for the Altaire. A work-in-progress cardiac imaging package, also designed for the Altaire, will allow coronary vessel angiography, using a multi-array cardiac coil.
  
• Sensitivity encoding technology, called preACQ (parallel receiver acquisition), is being developed to provide increased spatial and temporal resolution on the Altaire.
  
• Airis II upgrades include new pulse sequences, enhanced imaging capabilities, and expanded angiographic capabilities. Future R&D is focused on multi-array coils, particularly a head-neck coil and peripheral vascular coil, as well as advanced imaging sequences.
  
• Enhanced Airis II gradients support a slew rate of 30 mT, which improves echo-planar imaging.
  
• A breast coil designed to support diagnosis and biopsy on the Airis II is in development.
  
• The Airis II ³Scanogram² offers additional operator flexibility.
  
• DICOM capability adds modality worklist capabilities to storage and printing.

ONI

Last year the privately held start-up unveiled an ultracompact 1T extremity scanner. After working out the kinks uncovered at three clinical beta sites, the company has given the green light for full production to begin in early 2002.

• Improvements involve methods for damping out vibrations that cause MR signal interference. Fixes were related to methods for isolating these largely external sources of vibration.
  
• Upgrades include new pulse sequences, such as refinements affecting fast spin-echo.

Philips Medical Systems

With its acquisition of Marconi Medical Systems, Philips now lays claim to the widest selection of MR technologies, although several of these are works in progress. All members of Philips¹ family of Intera systems fit within the same compact footprint. Leading its line of open products is the Infinion 1.5T, an ultracompact cylindrical system, the in-house-designed Panorama 1T, and Marconi-designed 0.6T Infinion HFO (high field open), both of which are works in progress, and the 0.2T Panorama that Marconi was supplying to Philips prior to the acquisition.

• Positioning the Infinion 1.5T as an open product required a redefinition of the term ³open.² This was reasonable, according to the company, in light of the ³openness² of the Infinion¹s ultrashort bore.
  
• A Panorama 1T, operating in a company engineering bay, contributed images for display at the booth, supporting Philips¹ claims that the scanner is on track for commercial rollout in late 2002. The first clinical sites are due for installation at midyear.
  
• Intera 3T development supersedes that of the Marconi 3T whole-body product, which Philips has chosen to abandon. The very high field whole-body Intera is awaiting FDA clearance. The head-only 3T configuration is commercially available.
  
• A work-in-progress version of Philips¹ sensitivity encoding (SENSE) has been enhanced to boost spatial or temporal resolution by a factor of nine. A previous version of the technology, installed at more than 150 sites worldwide, increases resolution by a factor of four. SENSE is being added to the 3T development program as part of the body coil.
  
• Development of the Intera C/V, a 1.5T system optimized for cardiovascular work, has focused on expanding applications through multicenter clinical trials using SENSE to visualize the coronary arteries.
  
• Intera I/T, a 1.5T system optimized for interventional and therapeutic applications, includes the combination MRI/angio x-ray angio suite operating at the University of California, San Francisco, as well as more recent linking of the MR scanner to a mobile x-ray C-arm, featured at the Philips booth.

Siemens Medical Solutions

Products include the Allegra dedicated 3T head scanner, a work-in-progress 3T whole-body system called Trio, the Sonata 1.5T dedicated cardiac system, 1.5T general-purpose Symphony, 1T Harmony, 0.2T Concerto, 0.2T Jazz (supplied by Esaote), and the work-in-progress 1T Rhapsody. The syngo user interface is common to all these systems.

• Maestro software, slated for rollout in July, promises to increase throughput and expand applications for the high-field conventional systems. The software, which will be compatible with all new and installed Sonata, Symphony, and Harmony scanners, will push routine tasks associated with scanning into the background. Advanced applications involve cardiac, neuro, ortho, angio, and spectroscopic exams.
  
• Motion correction technologies built into Maestro include 2D and 3D PACE (prospective acquisitions and correction). 2D PACE, which freezes organ motion, will have a major role in cardiac imaging with breath-hold and free-breathing protocols. 3D PACE corrects motion due to patient movement and should be useful in functional imaging of the brain.
  
• Maestro¹s Super MIP (maximum intensity projection) automatically reformats data in body areas selected by the operator.
  
• An improved user interface, part of Maestro, allows the operator to tailor a display with different data types, such as a dynamic cardiac loop or ECG signal, along with certain slices of the heart.
  
• Integrated parallel acquisitions technique (iPAT) is Siemens¹ proprietary sensitivity encoding technology. The technology has cleared the FDA and will be released in July along with the rest of Maestro.
  
• 3D-Vibe optimizes body imaging results, combining dynamic tissue visualization with MR angio.
  
• Sprint gradients, which operate at 30 mT with a slew rate of 75, have been developed for the 1.5 and 1T products. The gradient system fills a gap between the Ultra (20 mT/50 slew) and Quantum (30 mT/125 slew).
  
• Trio, the 3T whole-body scanner being developed in collaboration with Bruker, was installed at its first clinical site two weeks prior to the RSNA meeting. Whole-body scanning includes extremity, spine, and abdominal imaging.
  
• Rhapsody entered its first clinical site just weeks before the meeting. The second installation of the 1T open scanner, at a site in the U.S., is scheduled for early next year. Clinical images obtained with Rhapsody and shown at the Siemens booth were drawn from angio, spine, ortho, and neuro exams.
  
• Concerto¹s new array of coils all work with the company¹s Integrated Panoramic Array for imaging the head, body, spine, and extremities.

Toshiba America Medical Systems

The Opart superconducting open-style 0.35T scanner saved Toshiba from obscurity in the mid-1990s. The company continues to enhance the product while seeking access to the high-field segment through the use of quiet technology built into its 1.5T Excelart Pianissimo, first shown at the 1999 RSNA meeting.

• SPEEDER, Toshiba¹s version of sensitivity encoding, was unveiled for use in high-field imaging. The technology will be released commercially in the fourth quarter of 2002.
  
• Cardiovascular imaging enhancements have been incorporated into the Cardiac 2001 package for Excelart. SPEEDER will support growth in this application area.
  
• Interactive control at 1.5T allows the scan plane to be adjusted on the fly. Using this capability, the operator can home in on suspected pathologies or other points of interest.
  
• A virtual-reality ride featuring 3D glasses in a corner of the booth touted the ³quiet² of Excelart Pianissimo.
  
• Opart Version 4 software, scheduled for shipping in January, upgraded the company¹s flagship product. Improvements emphasize productivity, including a friendlier user interface and features that allow customization to the operator¹s specific wants or needs.
  
• Opart sequences were expanded to include high-contrast, T2-weighted imaging, as well as steady state free procession, the Toshiba equivalent of FISP.
  
• Work-in-progress gradients are being developed to allow a 100-mT slew rate. The new gradient technology, which is at least a year from commercial release, is possible because of the extraordinarily stable, four-post design of the magnet, according to the company n