The pros and cons of 3T dominated discussions at each of the last few RSNA meetings but not the one in 2005. Vendors reached out in new ways, some to embrace clinical applications in the breast and heart and others to introduce functions aimed at boosting productivity, including software for operating MR by remote.
Aurora Imaging Technology
Aurora Imaging Technology offers a dedicated 1.5T breast MRI, featuring a 64-cm magnet bore and an enlarged elliptical focal point that enables imaging of both breasts, lymph nodes, and a segment of the chest in a single bilateral scan. Enhancements shown at the RSNA meeting boost the diagnostic power of the system.
- Ultra RODEO Plus uses specialized pulse sequences to suppress the visualization of fat and normal ductal tissue, which produce water and protein hot spots that can complicate MR images.
- AuroraCAD automatically recognizes and compensates for patient motion artifacts and distortions. It also simultaneously displays multiple image views and completes multiplanar reformats and maximum intensity projections.
- Aurora SUPERSHIM provides additional fat suppression to boost image quality, reduce artifacts, and visualize the axillae and breasts.
Oriented toward supporting biomedical research, Bruker has developed high- and ultrahigh-field scanners, collaborating with Siemens on the integration of its Total image matrix (Tim) technology into these systems. The recent development of a scalable receiver and transmitter architecture will enable new MRI applications in preclinical research and molecular imaging. The new architecture promises a fourfold increase in resolution, an expanded dynamic range, and raises signal-to-noise ratios. An order of magnitude increase in digital receiver bandwidth speeds up the acquisition times.
The Italian developer of extremity scanners chose Hologic to distribute in the U.S. two systems, the C-Scan and E-Scan. The two were featured at the Hologic RSNA booth in 2005. A third, Esaote's G-Scan, is an open scanner designed to image the limbs, joints. and spine. It tilts to place the patient in any position from supine to standing. The scanner, introduced by Esaote already at the 2004 RSNA meeting, has been installed in Europe and has received FDA clearance for marketing in the U.S. It has not yet been installed in the U.S., however, nor has Esaote assigned G-Scan as one of the systems to be distributed by Hologic.
The maverick of MR, Fonar is the only single-modality company still playing in this arena. It has carved a niche in orthopedic applications, particularly as they relate to the spine. The company's argument that its Upright MR provides information about patients in the standing position that cannot be obtained in the supine has won enough converts that the 100th such system was sited on Dec. 29. Fonar sought at the 2005 RSNA meeting to extend this argument to cardiac applications.
- True Flow Imaging of the cardiovascular system, a capability shown as an option on the company's Upright MRI, is designed to provide information about the size of the right ventricle as an indicator of pulmonary hypertension. The patient would sit, rather than lie down, during the scan. (Patients with congestive heart failure should not lie down.) Those with valvular heart disease might be better assessed, as they are standing in their normal physiologic posture, according to the company. Also benefiting from True Flow might be patients with myocardial ischemia resulting from coronary artery disease, as well as candidates for angioplasty or bypass surgery being assessed for coronary blood flow and patients with peripheral venous insufficiency.
- Open Room MR, first shown more than five years ago, received added attention in the days leading up to the meeting with the announcement that the company had shipped the first such unit to an orthopedic center in the U.K. The Fonar 360 will be assessed for its ability to support intraoperative MR procedures.
GE upgraded its high-end MR offerings and added an economically oriented 1.5T system. High-density coils developed for the company's previously launched HD 3T system were integrated into the new 3T system. GE plans to continue offering the HD 3T.
- Premium platforms Signa HDx 3T and the 1.5T Signa HDx are built on 32-channel architectures, featuring advanced reconstruction algorithms, and GE's specialized applications and technologies. These include releases of PROPELLER for motion-resistant brain imaging, VIBRANT-XV breast scanning, LAVA-XV body imaging, and TRICKS-XV time-resolved angiography. They are equipped with a new XVRE recon engine, advanced parallel imaging algorithms, new acquisition strategies, and an interlocking, high-density head-neck-spine coil system.
- Signa HDe, an economically priced, liquid-cooled 1.5T scanner, comes in four- and eight-channel configurations. Its small footprint takes about 30% less space than the flagship 1.5T system.
- Two new 3T peripherals are a breast coil, which supports multidimensional parallel imaging and biopsy capability, and a high-density hybrid extremity coil.
- A 1.5T peripheral vascular lower leg array provides images of the lower leg and foot vessels.
Hitachi Medical Systems America
Hitachi made its mark a decade ago in open MR scanning by releasing a succession of high-performance low-field scanners. After several abortive efforts to productize high-field MRs, the company in 2005 brought to market a system that may be well suited to the tastes of North American customers. Hitachi also released low-field open enhancements.
- Echelon combines the latest generation of compact magnet design with an eight-channel architecture and high-performance gradients capable of achieving a 30-mT gradient strength and 150T/m/sec slew rate. The system is scheduled to begin shipping by the end of first quarter 2006. Sales efforts will focus primarily on existing Hitachi MR customers.
- The next iteration, Version 5.0, is pending for Ascent, the operating system for the Airis II 0.3T and Altaire 0.7T products. The upgrades are intended to enhance image quality workflow, and clinical capability.
In 2005, the company released a nonmagnetic infusion pump designed for use in fields including 3T. IRadimed enhanced the capability of this device, called the 3850 MRidium Pump, with two new accessories at the RSNA meeting. One, a remote control option, is designed to allow staff to view and control the pump without staying in the MR suite during the scan. The second accessory, the 1057 MRidium Vented Syringe Adapter IV Set, allows delivery of small doses from 10 to 60 mL while using only 4 mL to prime the micr-bore tubing set.
The developer of MR contrast infusion pumps exhibited its next-generation Continuum MR Compatible Infusion System. The system provides measurements for an expanded selection of medications, sedatives, and anesthetic agents. New ease-of-use features reduce the potential for confusion and programming errors.
Minneapolis-based MR Instruments is leveraging proprietary technology, built on transverse electromagnetic properties, to create MR coils for use at 3T and above. The company made its first appearance at the 2005 RSNA meeting, displaying the technology under the brand Cheetah Coils. The 15-element head coils, designed for use on GE and Siemens 3T systems, were shown alongside 3T extremity coils available in large, medium, and small sizes. The company also announced the release in early 2006 of multichannel, transmit/receive, and multinuclei coils. The coils promise to generate up to 30% more signal and use 40% to 60% less energy than head coils now shipping with 3T scanners. Improved performance means shorter scan times, better images, and improved patient safety.
ONI Medical Systems
The company's OrthOne dedicated extremity scanner is the only one of its type with a 1T field. The company showcased the system with a new operating system that speeds data flow and a knee coil that offers improved signal-to-noise. More than 75 OrthOne systems have been installed worldwide.
Philips Medical Systems
Fitting scanners of differing field strength in the same compact frame has been a hallmark of Philips for a decade and a half. It is part of a broader focus on space management that has led the company to create patient-friendly scanners and environments, as well as easy-to-use technologies for the staff. The company has the only 1T open MR scanner, which is bolstered by two lower field open systems and the Achieva series of closed-bore 1.5T and 3T systems.
- SmartExam automates the planning, scanning, and processing involved in MR scans. Doing so decreases overall exam time, while increasing consistency and reliability. The algorithm runs on all Philips MR systems.
- Diffusion Body Scanning is designed to improve detection of lesions throughout the body.
- FiberTrak visualizes white matter fibers in the brain, providing a road map that neurosurgeons can use to avoid or minimize damage to the neurological pathways that control speech and movement.
- k-t BLAST boosts the speed of cardiac MR by a factor of five, reducing scan times for the heart and making cine cardiac MRI in a single breath-hold a reality.
- 4D-TRAK (4D Time-Resolved Angiography using Keyhole) makes MR angiography up to 60 times faster, allowing the visualization, for example, of feeding and draining arteries and veins in arteriovenous malformations.
- 2k Imaging, achieving 2048 x 2048 matrix resolution, allows users to zoom regions of interest.
Siemens Medical Solutions
Tim, the Total imaging matrix that serves as the foundation for advanced applications on Magnetom scanners, is the center of Siemens' MR universe. The technology has migrated throughout the company's high-performance scanners and is the focus of discussions on Siemens 3T and 1.5T products. The company complemented this coil technology with new software and clinical capabilities.
- Expert-i, which is pending FDA clearance, promises to allow expert collaboration on challenging examinations regardless of how far away the expert may be. The remote control technology allows distant operators to take control of the system on their PCs while patients are being scanned, inputting sequences and viewing data in real-time.
- syngo Susceptibility Weighted Imaging (SWI) helps visualize bleeding in stroke and brain trauma patients, contusions and shearing injuries, and minute intracranial vascular malformations.
- syngo Reveal is a body diffusion technique designed to help differentiate lesions throughout the body, particularly malignant from benign ones.
- syngo GRAPPA offers faster spine and cardiac imaging, offering a small field-of-view to provide very high spatial resolution.
Toshiba America Medical Systems
The U.S. arm of Toshiba had long depended on its low-field open MR scanner, the 0.35T Ultra (and its predecessor Opart) for revenues from the MR market. That changed a few years ago with the commercialization of the 1.5T Vantage, an ultrashort-bore system. Much of the attention in the Toshiba booth during the 2005 RSNA meetings was focused on hardware and software advances affecting Vantage.
- Vantage ZGV work-in-progress offers new sequences and a faster CPU, called Mach 8, which reconstructs 1230 images per second. Gradient strength is 33 mT/m. Slew rate is 200 mT/m/sec. The system is being evaluated at the Steinberg Diagnostic Medical Imaging Center in Las Vegas.
- F2 Edition/Version (V7) software and hardware enables improved applications for advanced imaging procedures, including Body Vision, Contrast-Free Improved Angiography, Fresh Blood Imaging, Water Excitation, and Whole Heart Imaging. F2 is compatible with Vantage AGV, MGV. and XGV platforms. (It will work on the ZGV, when it enters the market.)
- JET motion correction software allows patient data to be reconstructed, while sharpening and refining images that may have been unusable due to patient movement.
- Dual Uniform Overlay allows the use of two SPEEDER coils simultaneously, thereby extending the field-of-view. Using DUO, an entire torso from neck to pelvis can be acquired in a single exam.
- Breast SPEEDER coil, an advanced seven-channel coil, allows improved diagnosis and interventional procedures.
- Two work-in-progress coils are one for long bones such as the humerus and femur and another for a 32-channel head/spine coil.