Advanced visualization allows radiologists, surgeons, and other specialists to determine the extent of a medical problem and plan for treatment very quickly. The decision to operate, or not, can be made with more confidence. The thin-client model lets clinicians access and manipulate data from any computer. Advances under way will incorporate artificial intelligence, better integration with PACS, and the ability of users to choose and incorporate best-of-breed solutions.
Diagnosing appendicitis via CT can be difficult, says Gregg Gaylord, MD, director of diagnostic imaging at St. Nicholas Hospital in Sheboygan, Wis. With advanced visualization, he can put the images into multiplanar reformat for coronal or oblique views and spin the whole study around to be sure there is inflammation. "The decision can be made instantly."
Gaylord also uses advanced visualization to quickly determine whether stroke patients have clots. "We can have the CT angiograms up in minutes and see if there are clots and where they are in the brain. Before we had to have techs do reconstructions, and it was a mess." It took hours, sometimes even overnight, for the CT techs to perform the reconstructions.
In one case that showcases the dramatically improved patient care advanced visualization can deliver, a male patient was admitted with a one-week history of recurrent transient ischemic attacks. A CT scan of the brain was negative, and he was then referred for immediate MRI and MR angiography. A non-contrast MRI displayed multiple small areas of diffusion-weighted abnormalities in the distribution of the right middle cerebral artery and the right lenticulostriate arteries. Following the diffusion weighted study, a 3D time-of-flight non-contrast brain MRA was performed. The data set was automatically transferred from the MR scanner to the TeraRecon AquariusNET server and was immediately available for analysis on the AquariusNET viewer. Even before the remainder of the MRI study could be completed, Gaylord was able to determine that there were no large intracranial embolic lesions. The views were available without the MR technologists having to process the images on the MR computer. Using AquariusNET, all views were easily captured, saved to PACS, and were immediately available to the vascular surgeon and neurologist in their offices for review.
Thin-client capability is invaluable, says Gaylord. Think thin-client first and then worry about the workstation, he recommends. If you need full cardiac capabilities, then the workstation is still a necessity. However, "at some point, the thin-clients will be able to do that."
Steven Strobbe, DO, CEO, of Gulf Coast Medical Center in Port Richey, Fla., agrees that thin-client is the way to go. He uses Vitrea 3D software from Vital Images as well as the company's VITALconnect web solution. He knows the advantages of thin-client firsthand. He often spends time at his home in Alaska but can access his practice's workstation and manipulate the data through a web browser. "Thin-client is where everything is going." This ability to access and manipulate data from any location saves money and lets physicians be mobile.
Strobbe points out that not every practice can afford high-powered workstations, let alone $2 million for a 64-slice CT scanner. "Cardiologists need to be able to interpret exams — that's why thin-client networks are very important," he says. "They can sign in from a conventional PC and provide an interpretation from their office." And with coronary CT angiography emerging as the new gold standard for heart disease over cardiac catheterization, the process needs to be as efficient as possible. "You cannot have cardiologists and radiologists always have to go to high-powered workstations and work these cases up." The setup also lets imaging studies be viewed in a format that allows cardiologists and radiologists to quickly interpret from their office.
Three-dimensional imaging helps improve efficiency of heart disease cases by reducing the large data set to just the critical decision-making images. When a patient is scanned, there are 2,000 to 3,000 images. "You cannot look at them all. It would take forever," Strobbe says. Once he has a 3D heart to look at, he may only need to look at 100 images and sometimes, depending on the amount of disease, only 25 to 30 images.
With the rate of heart disease on the rise, determining which patients really need treatment is an important benefit of advanced visualization, says Robert Schwartz, MD, a cardiologist at the Minneapolis Heart Institute. "You can separate patients who have disease from those who have the start of disease. Advanced visualization provides a very clear differentiator. That's really a key application of the technology."
More clinical trials are needed to make this truly evidence-based, Schwartz says. But, "the clinical applications are very strong and emerging. Most people doing it understand that it is a key player of cardiac practice in the future. It's the cornerstone of coronary artery imaging."
Yet another upgrade
Laurie Sebastiano, MD, is a radiologist at St. Luke's Hospital in Bethlehem, Pa., using AW Suite 3D rendering software from GE Healthcare. She has been using GE software for at least eight years, and one advantage is it has all the same tools, buttons, and appearances that she and her colleagues are used to. The AW Suite is integrated with the GE Centricity PACS so that no one has to go to a freestanding 3D workstation to use the software. "Current versions of PACS software are so integrated that you can freely work between the two and cross-reference. We have 3D software rendering connected real time to 2D images."
The majority of images Sebastiano reads are body CTs. "When you have these kinds of large-volume studies that are thin section, multiple images, there's an advantage to looking at the data in more than one plane. Sometimes it's easier to look at it in reformatted coronal plane than in the axial." She finds that she can better appreciate an abnormality in the coronal plane. "And, it's particularly nice for viewing the aorta or other structures that run in a plane perpendicular to the acquisition plane. It's easier to understand vascular anatomy when you have the freedom to manipulate the planes."
Another benefit Sebastiano appreciates is preformatted protocols. "The less manipulation a radiologist has to do, the better," she says. "The easier they make it, the faster I can get to the other end." Those preset buttons also make the software easier for new users to use, she says. "CTA reconstruction used to be hard to do — you needed to know the finer details of how to use it." Now, a first-time user can do 3D cerebral circulation and use the function that automatically grows out vessels.
Answers in seconds
Elliot Fishman, MD, director of diagnostic imaging and body CT at The Johns Hopkins University School of Medicine in Baltimore, Md., uses a Siemens Medical Solutions Leonardo workstation in conjunction with Siemens 16- and 64-slice scanners for several years. The workstation provides high quality and high throughput, he says. "That workflow allows us to keep up with today's volume. People want answers in seconds, not days. We need to do things very quickly and accurately."
Another plus of staying with one vendor's products is the rapid "half-life" of computer equipment. Most equipment becomes obsolete shortly after you buy it. With that in mind, Fishman is always thinking about the new technology. "We are doing a lot of interesting research and development, so it's critical that our vendor has a good track record and is pushing the envelope."
One important application for Fishman is 3D postprocessing on renal donors. He looks at arterial anatomy for preoperative planning and determining whether someone is a good donor and if so, which kidney to select. "Accuracy is 100 percent" he says. That means he can be more aggressive in terms of selecting patients and can plan and operate more quickly and effectively.
Like other advanced visualization software users, Fishman has seen a dramatic impact on cardiac imaging. "We do 3D mapping to look for aberrant arteries and to quantify stenosis. In cardiac CT, he can create 4D imaging — 3D plus motion. A single 10-second acquisition lets him see valves opening and closing, measure ejection fractions, and more.
Another area where advanced visualization is having an impact is in trauma. Fishman uses it to define the extent of injury and determine the best operative approach. "About 30 percent of the time, advanced visualization changes the surgical approach," he says.
And progress continues. Technology is taking advantage of what computers can do, Fishman says. Artificial intelligence, for example, means clinicians have the benefit of a co-reader that can sort through data and make suggestions. For more advances, growth is required in both abilities and applications. "You can develop the best workstation, but if you don't have the best CT data, it wouldn't be that helpful. You need a combination of quality, dynamic data with processing." Advances in cardiac imaging have only happened because clinicians can now obtain great cardiac data, he says. "Nobody developed ejection fraction functions when you couldn't see the coronary arteries well."
Incorporating advanced visualization into PACS and making it readily accessible to radiologists is essential, says James A. Brunberg, MD, professor and chair of the department of radiology at the University of California-Davis. That can be a challenge, he says, because many vendors don't have an application programmer interface that easily allows for this. "Several vendors would prefer that any use made of advanced imaging techniques be entirely through their brand name rather than allowing radiologists to choose best of breed," he says. Some vendors have improved in that area, but not all, he says. Brunberg uses Voxar 3D products from Barco, a company he says is leading the way.
Other advances in the field mean that individual workstations will become more and more powerful. "Microprocessor manufacturers are looking at ways to expand technology or incorporate simultaneous technology into their microprocessors so one workstation has the memory and computing power to perform multiple tasks," Brunberg says. Aside from the time duration required to read one study, radiologists frequently interrupt that reading to open another study. "That makes you lose attention to the detail of what you're looking at," he says. More powerful workstations mean they won't have to sit waiting while the thin-client interacts with a distant computer to retrieve data. "The radiologist won't have to physically or virtually leave by calling on a remote computer. Having it all on the radiologist's workstation I think is going to be a major advantage."
The computer gaming industry has led the changes and advancements coming to advanced visualization, Brunberg says. "It has allowed for the construction of video cards that have the capacities that are sufficient for what we need in diagnostic radiology." Also, new computer chips will dramatically speed up microprocessor capability, he says, letting a single workstation provide regular viewing plus interactive as well as motion and speech recognition.
Challenges still exist
Even as advanced visualization technology is improving efficiency and patient care, there are challenges. The learning curve for radiologists shouldn't be underestimated, Brunberg says. But once they become well versed, "they are defining the optimal software packages for what they need and what they want to do."
Another challenge is meeting the desire to incorporate best of breed, he adds. Finally, the point of commitment is difficult for some users, Brunberg says. "Should they jump on board with something that's available right now or wait another six months and see what else is going to be developed?"
There's no doubt that each user must address these questions. But anyway they look at it, "everything is moving totally digital," says Strobbe. "This is the most exciting field in medicine in the last five years. This new technology replaces invasive procedures so we can reduce cost, mortality, and morbidity."