June 2014

Advancing Visualization
By Leesha Lentz
Radiology Today
Vol. 15 No. 6 P. 10

By providing more than just images, radiologists can bolster their consulting relationships with other physicians. Quantitation is proving a good first step.

Advanced visualization typically brings to mind 3D images. However, in the coming era of value-based care, providing the image may not be enough.

“We thought that our job originally was to say, ‘Here is the data set and the 3D volume, and now it’s up to you to do the quantitation if you believe it’s worthwhile,’” says Paul Chang, MD, FSIIM, a professor of radiology and the vice chair of radiology informatics at the University of Chicago Medical Center.

He says radiologists originally were morphologically driven, providing 3D images along with data sets and expecting their clinical colleagues to make their own quantitative assessment. But there’s a growing sense that radiologists should take greater responsibility in the role of quantitation. “I think one of the signs of the maturation of advanced visualization is that we in radiology understand that we have to evolve beyond purely the morphologic, the structural, the anatomic,” Chang notes. “We have to move from that to functional, quantitative, physiologic data.”

As radiologists embrace quantitation, they’re exploring how to use advanced visualization applications to better patient care and potentially increase collaboration between themselves and clinical colleagues. “One thing we’ve seen [from radiologists] is the desire to collaborate with other clinicians to evaluate clinical decisions and to determine the diagnosis and treatment plan for their patients,” says Nichole Gerszewski, a brand manager at Vital Images, a Toshiba Medical Systems Group company.

For example, Gerszewski says radiologists are adding quantitation to reports and adding value to their services with applications such as Vital’s TAVR (CT Transcatheter Aortic Valve Replacement), which can measure the aorta and provide that information to the cardiologist. “Going above and beyond like this is becoming more common,” she says.

Procedure Planning
Bradley Erickson, MD, PhD, a radiology professor at the Mayo Clinic in Rochester, Minnesota, agrees that in the past, the technology was about visualization, but it’s increasingly becoming more about quantitation. At the Mayo Clinic, he says, radiologists and other physicians use advance visualization tools in multiple clinical areas, particularly endovascular treatment planning.

“Advanced visualization is used as a step in planning endovascular procedures,” Erickson says. “They are starting to create custom grafts based on measurements from a CT angiogram. For instance, we can measure the size of the aorta at various points as well as where important vessels branch off of the aorta so that a company can then make a custom graft that matches that particular patient’s anatomy. And without that ability to make those unique patient measurements, [that customization] really isn’t feasible to do. If the endovascular graft has a branch point that’s not where the patient’s branch point is, then it doesn’t do any good.”

The clinical applications allow for aortic measurements, which then may provide more data for cardiologists and surgeons when planning treatments. “Clinicians want to make sure they are getting all the information they need, and radiologists now are able to provide richer information for confidence in clinical decisions,” Gerszewski says.

She adds that Vital representatives recently visited an end user of its TAVR application at a prominent cardiovascular facility, where a multidisciplinary team meets weekly to thoroughly review and discuss patient candidacy for TAVR procedures. “They share the images and show what the issues are in the patient and patient history,” Gerszewski says, “and they use these images to collaborate with each other to determine if TAVR is a good option for each patient.”

Gerszewski says radiologists “are helping referring physicians by building their armamentarium and providing them with the tools they need to make efficient and informative decisions about their patient’s diagnosis [and treatment].”

In addition to cardiology, quantitation also is important in brain studies and assessment. “One example where we do measurements of the brain is in some patients that have epilepsy that just can’t be controlled by medication,” Erickson says. The treatment involves surgeons removing the part of the brain that excites the epileptic episodes. Planning this therapy requires precise measurements because “the differences can be subtle enough where they are not visually apparent, and you really do need to do the precise quantitation to identify the difference.”

Lawrence Tanenbaum, MD, an associate professor of radiology at Mount Sinai Hospital in New York, says he uses clinical applications from Olea Medical, especially Olea Sphere software, for evaluating patients with acute stroke or brain tumors. Advanced visualization “significantly enriches the value of the imaging examination,” he says. “Many times, without the additional physiologic information, our exams aren’t as helpful to our clinical associates as we would like them to be. Validated, accurate, and reliable quantitative assessment takes us to the next step in disease characterization.”

While quantitation of morphology has been effective in aiding specialists and clinical colleagues in treatment planning, Chang says advanced visualization has entered a new phase, one that may prove important in cancer assessment. “Advanced visualization has gone beyond just merely morphology, even quantitation of morphology and anatomy,” he says. “It’s now going into function so, for instance, we are now providing advanced visualization that deals with perfusion, which is becoming very important in oncology. The treatments for cancer now have become so advanced that some of these treatments do not manifest themselves by completely killing or eliminating the tumor but rather making it indolent.”

In other words, cancer treatments may no longer reduce the tumor’s size, which was used as a marker of the treatment’s effectiveness. Instead, the tumor may be made to slow and remain unchanging; therefore, radiologists can’t rely on physical measurements but rather on physiology through perfusion. Chang says it’s becoming increasingly important to combine all of the information—3D images, morphology, and physiological or functional quantitation—to provide a well-rounded report to aid in patient care.

According to Chang, advanced visualization can provide tools that do multimodality correlation, giving users the ability to quickly view in one image a combination of both the morphology and the physiology, showing “the diffusion, the perfusion, and the temporal perfusion in one consumable, easy-to-understand representation.”

Utilizing Automation
When doing quantitative assessments, it’s imperative that radiologists provide consistency, which may present a problem when considering the variability when different radiologists use the clinical applications for different measurements. To mitigate human error, radiologists are trying to maintain consistency through training and software developments.

Tanenbaum emphasizes the importance of accessibility to advanced rendering around the clock and throughout the enterprise when dealing with patients with acute stroke. He says that Olea Sphere allows institutions to avoid concerns over variable technical personnel training levels across shifts. “Say a patient presents with stroke at 3 o’clock in the morning. Having the script-driven advanced visualization software process distribute the rendered perfusion images without the need for technologist or physician interaction is very powerful—trusting that the output is quantitative, accurate, and reliable is critical,” he says.

At Erickson’s facility, technologists are trained to obtain these measurements, especially when quantitating for cardiology. The training can reduce the variability that can occur and help technologists maintain a consistent output, especially if they’re accustomed to measuring areas such as the aorta’s opening every day. While a physician could perform this task, he or she would have to be available around the clock to meet the demand.

Improving Collaboration
Erickson says the best way to maintain collaboration between radiologists and other specialists is through clinical care conferences. For example, he attends specialty conferences in epilepsy and head and neck care. He says radiologists and specialists can discuss the more challenging cases at these events, and they may provide an opportunity for radiologists to present quantitative solutions.

“Sometimes people will say, ‘I wonder if you could measure that and whether it would help us in doing a better job in taking care of the patients,’” Erickson says. “And if there’s a radiologist around, they could say, ‘We can measure this or that, and that may help you better determine the correct implant if it’s orthopedic surgery or the difference in the brain or help in working with a company to develop an endovascular stent graft.’”

Chang believes that while advanced visualization does allow collaboration through the exchange of 3D images, collaboration can and must extend even further than that. “Advanced visualization is just a tool. It doesn’t mean we’re going to foster deep meaningful collaboration with our colleagues,” he says.

Real collaboration requires more than the radiology report. “So let’s say I do advanced visualization, all the fancy stuff that combines the 3D with the quantitation. The challenge we have now—and the limitation—is what’s the end result of that? It’s still the same-old narrative-based radiology report. Even with structured reporting, it doesn’t capture the richness of advanced visualization,” Chang says.

He sees the next step as combining advanced visualization’s tools and clinical applications with robust enterprise-level communication. He says children provide the clues to a better communicative platform. “When you look at our kids, they have 20 different ways to talk about trivial things with each other through Facebook and Twitter, but a lot of that is collaboration,” he explains. These social tools are real-time, multimedia solutions, and these qualities could inform a richer, more collaborative tool that fully realizes the abilities of advanced visualization, he notes.

Quantitation may be an important first step in collaboration with specialists and in patient care, but it will take a lot of ingenuity and creativity for advanced visualization to reach its potential for enterprisewide communication and collaboration that Chang envisions.

“I think a lot of the pushback on advanced visualization was that a radiologist would say, ‘Well, we don’t need that to make a diagnosis,’” Erickson says, “and that’s arguably true, but if you see the role of the radiologist as to help take care of the patients, then advanced visualization can be helpful in planning therapy and in communicating to the patient. So if we see our job as more than making a diagnosis but actually taking better care of patients, then advanced visualization can become an important part of our care process.”

— Leesha Lentz is an editorial assistant at Radiology Today.