In the beginning there was the x-ray. And as a medical tool—though revolutionary—it was very limited. It would take the introduction of contrast agents—bismuth and barium—for the new technology to have a broader use (in this case being able to image the lumen of the intestine).

This point of convergence occurred about a century ago; and since then, the convergence of technologies and methodologies have allowed radiology to evolve into one of the key elements of health care’s tool kit. And while technological convergence in radiology is nothing new, the speed at which it is transforming imaging is.

Among the most notable areas is the use of contrast agents to diagnose the early stages of such diseases as Alzheimer’s, more rapid computational abilities, the combination of different modalities, and the use of imaging to enhance evidence-based medicine.

A Study in Contrast

While the use of contrast was the first technological convergence for radiology, James Thrall, MD, FACR, vice-chair of the American College of Radiology’s Board of Chancellors, notes that the use of new agents has moved imaging from the level of studying the organ to the molecular. “Now, we’re looking at the micrometers and nanometers. We’re looking at the metabolic processes,” he said.

Avid Radiopharmaceuticals Inc, Philadelphia, is among the companies leading the way to this new molecular imaging. The company is currently entering a second-phase study of a radiopharmaceutical designed to help detect the early occurrence of Alzheimer’s disease. The agent looks for amyloid plaque, a signal that a patient is suffering from Alzheimer’s.

The first phase of the study imaged about 100 patients, according to Dan Skovronsky, MD, PhD, president and CEO of Avid. The agent has yet to win US FDA approval. The convergence point is between the agent and PET/SPECT.

At this point in its development, Skovronsky sees the imaging study as one that will be handled by a nuclear radiographer. Currently, patients are coming from neurologists—who suspect that their patients may be prone to Alzheimer’s—as opposed to primary care physicians.

Skovronsky sees numerous benefits for the use of this radiopharmaceutical (which has yet to be named). The primary one is that he hopes it will become a way to prevent or manage Alzheimer’s. “You’ll be able to see if the patient has Alzheimer’s even if they are presymptomatic,” he said.

“If you can image the patient when they’re presymptomatic, then you can intervene earlier. Our hope is to make Alzheimer’s preventable.”

The advantage of metabolic and molecular imaging, according to Thrall, is that it helps to identify events before organ changes occur. “By going to the biologic source of the disease, we can detect it sooner in the occurrence of the disease,” he said. In the case of Alzheimer’s, the disease can begin its destructive work up to a decade before symptoms occur.

Skovronsky also hopes that the test will become part of the general battery of tests that a patient will undergo at key moments—like mammography and colonoscopy. He also points to the fact that the test itself is easy and robust enough to make it a tool that the medical community will want to adopt.

The other benefit the contrast agent has is that it can help pharmaceutical companies to identify if their drug regimens are helping to slow or cure Alzheimer’s. This is a natural development, according to Skovronsky. “Imaging and treatment have to go hand in hand,” he said.

Avid also is developing other products to screen for Parkinson’s disease and diabetes. Skovronsky does not see Avid’s imaging products as an end all. In fact, he hopes that someday there will be better and simpler nonimaging screening devices available, such as blood tests.

Thrall notes that molecular imaging is building on work done in the pharmaceutical industry. “Every molecular imaging test has to have targets,” Thrall said. “Radiology is not inventing the targets. We’re just hitting the targets identified by the pharmaceutical industry.” He notes that the number of agents available today—a handful—will likely increase to the hundreds as the efficacy of these tests are proven.

While contrast agents offer important diagnostic options for radiologists, Thrall identifies the computer as among the most important convergences.

A New Era

Thrall notes that radiology is entering an era of massive computing. He has observed this convergence firsthand during his 40-year career.

Thrall, who also is a radiologist at Massachusetts General Hospital, has been helping to study the benefits of supercomputing. “Iterative reconstruction yields spectacular gains,” he said. These gains include a reduction in radiation dose—by up to one fourth—and/or a benefit in improved resolution (though higher resolution can mean a higher radiation dose for the patient).

However, this ability to do massive supercomputing is still more a promise than an actual fact. “It still takes an hour to do the reconstructions, so it’s not practical today,” Thrall said.

Improved image processing also can help pharmaceutical companies, says Terry Hisey, vice chairman and industry leader of Deloitte’s Life Sciences Practice, including helping to design drug trials and accelerating the trial process. Hisey is a co-author of a Deloitte white paper, “Managing Pathways to Convergence in the Life Sciences Industry,” which examines points of convergence.

While the supercomputing technology is promising, Thrall cautions that much of the technology that will allow for the iterative improvement of radiology is coming from business and consumer applications. “We in radiology are the accidental tourists on the supercomputer information highway,” he said.

Computing and contrast agents are obvious points of convergence for radiology, but not all advances come from a different industry. Convergence can also come within radiology itself.

Thrall calls this type of convergence a “mash up,” and it involves two different data sources. An example of this is PET/CT, which is proving to be very successful. Thrall says that the next mash up will be PET/MRI, which will be used in neuro research.

The PET side of this new hybrid will be used to image neurotransmitters. The MRI side will be used to measure the blood flow.

Convergence not only is a question of changing the technology, but the way things are done—such as in evidence-based medicine.

Evidence-based Medicine

Paul Keckley, PhD, executive director of the Deloitte Center for Health Solutions, spent several years as the executive director of the Vanderbilt Center for Evidence-based Medicine, associate professor at Vanderbilt University School of Medicine, and an associate professor of Health Management at the Owen Graduate School of Business. While there, he was involved in several convergence projects. He oversaw clinical outsourcing ventures involving care team training, clinical information technology, data management, and evidence-based pathway construction and integration. It was while at Vanderbilt, working with 2,400 clinicians internally and externally with health plans, insurers, and joint ventures, that he helped to develop protocols to embed evidence-based systems within government health care.

Key among these was imaging. “This was important and central to our focus because most evidence-based [approaches] are diagnostic and therapeutic,” Keckley said.

He notes that the therapeutic side of evidence-based medicine has a “fair momentum,” and now the focus is on the diagnostic side of the equation. “What we’re adding now is a whole new area; a natural ying-yang,” Keckley said.

Lack of Resources

Imaging is dependent on many things, including raw materials. And while convergence is an engine of change, the fuel that keeps radiology running is becoming scarce.

This is because the last producer of Technetium (Tc-99m), Atomic Energy of Canada’s Chalk River reactor in Ontario, ceased production recently. The production facility was shut down after inspectors discovered, during routine maintenance checks, that the plant had been operating for a year “without the required emergency power system connected to two cooling pumps,” according to a December 12 Associated Press report.

About 50% of Technetium, the most common isotope used by US radiologists, comes from this one source. Though urgent cardiology studies can be performed with Thallium-201, Technetium is the key element in bone, lung, and renal scans. “This points to vulnerability [of imaging],” said Manuel Brown, MD, chairman of the American College of Radiology’s Commission on Nuclear Medicine. “It’s very important to have a reliable source of radioisotopes.”

According to a press release issued by the American College of Radiology, Mallinckrodt Medical—a subsidiary of Covidien—was able to secure the radioisotope from its production facility in the Netherlands. However, the company could not make up the deficit caused by the closure of the Canadian factory.

The good news is that the Canadian government, according to the Canadian Press, took steps to reopen the factory, bypassing its own rules and suspending oversight by the Canadian nuclear regulatory authorities for 120 days. Ultimately, on December 16, Atomic Energy of Canada returned its National Research Reactor to service.

But this might be a quick fix for a more fundamental problem. “Having radioisotopes is really critical to the delivery of medicine in the United States,” Brown said.

—C.A. Wolski

One example of this diagnostic convergence is with interventional radiology and oncology, which is leading to the use of nontissue samples in order to diagnose cancer. “Interventional radiology has had the most significant diagnostic shift,” he said.

While evidence-based medicine is a byword for many clinicians, pressure points are building over the use of imaging with a concern that there is not enough benefit from the increasing numbers of imaging tests. Keckley argues that by using the new capabilities and the diagnostic advantages “with the signs and symptoms of disease, you get better data early on.”

This form of evidence-based medicine, which is impacted by the continuing convergence of new technologies, is causing core competencies to change as well. “Now you have to learn bedside. It’s becoming a lifelong-learning approach,” Keckley said.

Keckley has spent much of his career—including a stint working with Great Britain’s National Health Service—examining, developing, and expounding evidence-based approaches. But he is also—not surprisingly—cautious about the changing face of radiology and medicine in general. “[The new technologies] are cool, but they’re not everything,” he said. “The neat part about evidence-based medicine is that you can never declare victory.”

No matter the point of convergence, one thing is inescapable; the practice of radiology is changing and converging as well.

Changing Role of Radiologists

Thrall says that considering that 25% of United States-based radiologists are from another country, there should be little concern that anyone practicing today will be out of a job. But that does not mean that the job is not changing. “I think that increasing sophistication will force more specialization. That’s where there’s value,” he said. “There will be increased stratification. In smaller markets, there will still be a need for a generalist. What we’re going to see is an increasing horizontal stratification from traditional generalist to molecular imagers who are just as knowledgeable as neurologists. We need both kinds of radiologists.”

Deloitte’s Keckley sees the general radiologist as an endangered species. But this general observation generates more questions for him. “How do professional providers—the soft tissue guys—adapt to the ?intrusiveness’ of more accurate to earlier stage diagnosis? How do we change the treatment algorithm?”

Keckley notes that we are already seeing changes in other ways. He sees the Marcus Welby model of the older, less evidence-based, autocratic physician giving way to a younger, more tech-savvy, and increasingly diverse (about one third of radiologists are now women) one. “It’s a different world,” he said.

Hisey gives a snapshot of the future role of the radiologist. “We believe that the further out the convergence continuum the radiologist won’t just be imaging, he’ll be the disease-management coach,” he said.

Imaging centers and hospitals also will experience a change in their roles in the health care continuum and the competencies they will need to have. It will all depend on whether these organizations offer primary or tertiary levels of care, Thrall said. If it’s the latter, they will need to offer much more sophisticated models of care than the former.

Deloitte’s Hisey predicts that the far future may see a world where “smart imaging” technology will be part of every home and residents will be able to image themselves and send it to a radiologist for interpretation. He also predicts an increase in retail imaging—such as the mediclinic, and remote reading.

Thrall also sees that the internist’s role will change as well. They will increasingly need a broader base of knowledge, one that a single human being cannot possibly retain in order to make the right imaging decisions for their patients. Again, this is another point of convergence. “At Mass General, we have a computer order entry system,” Thrall said. “It’s a matrix of 12,000 entries that cover the reason and what test the primary care physician is ordering. The system then gives a reasonableness score and other imaging options, which have hotlinks to concise entries about these tests. For instance, when is it efficacious to order a CT/MRI for a headache?”

No matter how convergence is affecting them, Hisey says that radiologists have more opportunities today. “It’s changing the way they do things and what they do,” he said. “I don’t think they should be scared. I think they should be enthusiastic and seize on [the convergences].”


C.A. Wolski is a contributing writer for Medical Imaging. For more information, contact .