Volumetric imaging drives 3D processing portability

December 1, 2005

Radiologists can't get around the surge in volumetric imaging. Sixty-four-slice CTs and 3T MRs are producing data faster then ever. But relief is on the way.

Radiologists can't get around the surge in volumetric imaging. Sixty-four-slice CTs and 3T MRs are producing data faster then ever. But relief is on the way.

Vendors at the RSNA meeting are expected to showcase numerous ways to handle these data. Many involve thin-client solutions, a technological trend hatched in the wake of multislice CT and weaned on the realization that clinicians throughout an enterprise need access to postprocessing techniques, not just the few with high-performance, stand-alone workstations.

That is not to say these workstations have completely lost their place. Specialized techniques, such as those focused on a single modality or addressing one application, may require computing-intensive platforms. But even workstations designed to handle the most advanced and specialized capabilities are being equipped to support multiple modalities and other applications.

Exhibitors at the RSNA meeting will display workstations optimized for digital mammography but capable of displaying images from other modalities. Software developed for virtual colonography will migrate from dedicated to generic platforms.

PACS and other specialized thin-client networks already support a vast array of postprocessing capabilities, which vendors are tweaking to improve ease of use and productivity. In October, GE Healthcare released a software option for its Advantage Workstation that extends advanced processing to users logging into the network from a remote PC or laptop. AW RemoteAccess allows multiple users to access a single host to perform interactive maximum intensity projection and multiplanar reformatting tasks on exams available at the workstation. Alternatively, a single remote user can take over the workstation remotely, performing functions as if the work was being done in person.

TeraRecon has built an entire network on the concept of providing remote operations. Its AquariusNET is a 3D enterprise server/thin-client solution that integrates advanced processing tools into the PACS workflow. At the RSNA meeting, TeraRecon will introduce upgrades to its AquariusNET that allow operators to shuttle between 2D and 3D, including some of the most advanced postprocessing capabilities available, according to Steve Sandy, vice president of marketing for TeraRecon. Among these will be virtual colonography flythoughs, advanced segmentation of the cardiac tree, bone removal, stent-graft planning, and brain perfusion analysis. These features are built around robust algorithms that reduce the time needed for reconstructions.

Barco has upgraded its Voxar 3D software to handle the large studies advanced CT and MR scanners produce. Version 5.1, which will be featured at the RSNA meeting, reduces reading time and improves productivity, according to the company. Like its predecessors, Version 5.1 is integrated into PACS developed by various vendors.

"Radiologists' workflow is centered around what they do on their PACS, so having 3D on their PACS workstation is really important," said Carter Yates, senior director of marketing of Barco's Voxar product group.

Layered on top of Barco's new 3D software is VesselMetrix, a vascular analysis module. The software helps assess stenosis, plan stents and stent-grafts, and track the stent-grafts' effectiveness.

VesselMetrix simplifies reading both CT and MR angiography studies by segmenting enhanced vessels from surrounding tissues, locating stenosis and aneurysm contours and diameters, labeling key features, and creating summary image sets. The radiologist need only identify the anatomic region of interest and the extent of the analysis to be done.

"It will find the vessel, pick relevant views, and, depending on what is being done, search for a stenosis or aneurysm, plan a stent or stent-graft, or track the stent-graft that was done," Yates said.

This kind of automation is essential to improving productivity, as is designing the software to fit seamlessly into the everyday routine.

"Making these tools easy to use is the key to making them effective for radiologists," he said.

Barco is not alone in its advocacy. Viatronix has pioneered automatic postprocessing, most notably for virtual colonoscopy, but also for calcium scoring and vascular exams. The software was previously attached to a particular hardware platform. At the RSNA meeting, Viatronix will offer the option to purchase just the software.

"As long as customers have a high-end workstation, they can buy our CD and take advantage of our advanced postprocessing techniques," said Zaffar Hayat, Viatronix president.

Added to the vascular model this year is the capability of analyzing the coronary arteries. As with large vessels such as the carotids, aorta, and iliac arteries, the data from the coronaries will be automatically processed, labeled, and isolated in 2D and 3D. The automatic postprocessing is especially important for specialists who read many cases per day, said Frank Dachille, Ph.D., director of R&D for Viatronix.

"The default software that comes with a scanner can do the job, but it will take 40 minutes on average per case. That is not acceptable to someone doing 20 cases a day," Dachille said.

Merge Healthcare offers RIS/PACS, advanced visualization, and clinical imaging applications, as well as Web-enabled image distribution solutions through its Cedara Software subsidiary. Customers want total integration of data in the back end (DICOM), in the workflow (clinical exam), and in the downstream product delivery (report), said Tim Kulbago, vice president of product innovation for Merge eMed.

"Plumbing, workflow, and delivery-if you don't have all three, you only deliver a fraction of the value," he said.

Cedara serves the high-end user with products such as its breast ultrasound computer-aided detection system, while Merge serves the second-tier market with its concept of unified single-system strategy. This involves integrating RIS, PACS, clinical applications, electronic medical record, and more with a single desktop/single system.

Cedara will showcase I-ReadMammo, a soft-copy reading workstation that saves users time by allowing them to determine image layout, presentation, and view order. The company will also feature B-CAD, the first CAD system for breast ultrasound, which will be shown integrated with the I-ReadMammo.

Merge has for years offered its e-Film Workstation for the less experienced user or those new to the digital world. The low-cost software product can be downloaded from the company's Web site. Now users can purchase plug-in programs that enable them to perform higher end exams such as virtual colonoscopy, calcium scoring, lung nodule detection, and 3D/4D reconstruction.

Vital Images has transformed advanced visualization and analysis of CTA and MRA data with its Vitrea platform. But access to advanced visualization functionality has been limited to locations where Vitrea was present. ViTALConnect allows radiologists to use PCs or notebook computers to access visualization using a thin-client Web-enabled browser. Early applications were limited to 2D images, but that will change, according to Jeremy Rollie, senior marketing manager. The company now offers the ability to use ViTALConnect for 3D and 4D visualization.

"The biggest trend in the market now is to have total image distribution. Radiologists want to sit in one place, whether at home or the hospital, to do image manipulation, and they want it integrated with PACS and RIS," Rollie said.

Low-cost but powerful solutions may spike in the future, as technologies developed for the video gaming market find applications in medical imaging. Video game graphics cards are the first to have an impact.

PACS developer Emageon, which provides key components designed to manage large volumes of medical images, is taking advantage of OpenGL, a standard for graphics cards. The company has already released a software package using OpenGL for 2D imaging and will showcase OpenGL for 3D navigation at the RSNA meeting, said Mark Gehring, chief technical officer of Emageon.

Emageon is leveraging OpenGL to boost the postprocessing performance of its PACS. It will provide radiologists with a hanging protocol that might include a 3D volume-rendered image in one view port, a multiplanar reconstruction in a second, and other protocols in a third.

"It's all part of the workflow, and the user interface is consistent," Gehring said. "Radiologists do not have to learn a different set of tools to use the 3D imaging."

Mercury Computer is taking this idea to the next level, adapting the microprocessor that will power Sony's PlayStation 3 for medical imaging products. The Cell processor was developed over the last four years by IBM, Toshiba, and Sony Group. It combines eight synergistic computing elements and a controller into a single 64-bit central processing unit, all sharing the same memory and delivering peak performance of more than 200 billion operations per second.

The first products using this technology could debut at the RSNA meeting, and they will definitely be onboard medical imaging systems in early 2006.