Diagnostic Imaging at 30

November 2, 2009
James Brice

Volume 31, Issue 11

These are hard times for magazines, especially ones that devote themselves to medical practice.

These are hard times for magazines, especially ones that devote themselves to medical practice.

The industry has experienced a historic shift from print to web-based communications just as many of the companies that have traditionally supported Diagnostic Imaging have reduced their advertising because of the current imaging equipment sales recession. The slowdown stems from lower federal reimbursement rates due to the Deficit Reduction Act of 2005, the financial crisis of 2008, and the uncertainties of the healthcare reform debate of 2009.

It's a hell of a time to celebrate our 30th birthday. But if our past can be taken as prologue, then many lessons about past downturns and recoveries can be found in the 360 issues that document our 30-year history. Slumps have happened before. Diagnostic Imaging was also awfully thin in the healthcare reform year of 1993. Display advertising sales dropped by half that year, while pundits claimed that radiology would never be the same.

Fast-forward to 1997 and our financial fortunes have fully recovered in a record year for imaging equipment sales. Rather than losing one-quarter of their income as predicted, radiologists would see their average compensation more than double by 2005.

Stark differences can also be seen in Diagnostic Imaging's coverage of healthcare reform in 1993 and 2009. Sixteen years ago, we sat back passively and let reform unfold and then unravel on its own before considering in our pages what it all meant for radiology. This time Diagnostic Imaging has a Washington-based editor and a daily news portal at www.diagnosticimaging.com to follow the movement of legislation through the House and Senate. Our coverage is far superior to what it was 16 years ago.

And the radiological practices and imaging modalities that have served as the focus of our coverage for three decades are also improved. The American College of Radiology's Congressional lobbying efforts have been broadened and strengthened to deal with the unremitting challenge of legislative threats since DRA passage, according to Dr. James Thrall, chair of the ACR board of chancellors.

QUALITY AND SAFETY

In terms of quality and safety, the ACR intervened when the unregulated expansion of breast imaging services threatened public confidence in screening mammography. Reports in Diagnostic Imaging described formation of the ACR's mammography accreditation program in 1987 and how Congress used it as a model for Mammography Quality Standards Act regulations implemented in 1992.

Great improvements in mammographic image resolution, reading quality, and dose exposure were made during Diagnostic Imaging's first decade, but the quality of mammography practice remained uneven until the ACR and federal government intervened, according to Dr. Stamatia Destounis, a mammographer with the Elizabeth Wende Breast Clinic in Rochester, NY.

Certainly, the patient benefited from all this regulation because the equipment was accredited, the technologist was accredited, and so was the doctor performing the study, she said.

At the ACR, controversies concerning field strength and MRI drew our attention as the organization's accreditation program was expanded to that modality and to breast ultrasound, stereotactic breast biopsies, CT, MR, PET, nuclear medicine, and radiation oncology.

The quality of radiological research has improved since the creation of the ACR Imaging Network in 1998. More than 30 multicenter clinical trials arising from ACRIN's decade-long collaboration with the National Cancer Institute have addressed the need for evidence by measuring the clinical efficacy of digital mammography, CT-based lung cancer screening, CT colonography screening, and other emerging imaging applications.

Diagnostic Imaging reported on ACRIN's involvement with the National Oncologic PET Registry from the program's inception in 2005, to test the impact of a wide range of new cancer-related applications on patient management, to the publication of results in 2009 that led the Centers for Medicare and Medicaid Services to grant reimbursement for those procedures without reservation.

The magazine devoted a cover story in February 2002 to an exclusive interview with Dr. Elias Zerhouni, the first radiologist to be appointed chair of the National Institutes of Health. Zerhouni placed the potential of diagnostic imaging in context with his vision of medical research based on the genetic underpinnings of disease and molecular-level opportunities for earlier diagnosis and improved treatment.

Diagnostic Imaging also tracked the debate leading to the creation of the National Institute of Biomedical Imaging and Bioengineering, a national institute devoted specifically to medical imaging research. In June 2008, an exclusive interview with executive director Dr. Roderic Pettigrew described how medical imaging will contribute to the proactive practice of diagnostic imaging in the 21th century.

TRACKING SELF-REFERRAL

Diagnostic Imaging has tracked physician self-referral since Dr. Bruce Hillman's damning studies of the practice in the early 1980s helped lead to federal Stark laws prohibiting it. We covered loopholes in the law and developed a close association with Dr. David Levin and Dr. Vijay Rao and their research on Medicare utilization growth among cardiologists and from in-office self-referral.

Dr. Alan Kaye, president of Advanced Radiology Consultants in Bridgeport, CT, blames in-office self-referral for the transformation of high-tech imaging from its status as the darling of the medical world to a target for regulation and rate cutting.

“Not long ago, imaging was ranked third on the top 10 list of medical developments in the twentieth century,” he said. “Now, that distinction is lost because of the focus on costs and the excesses of self-referral.”

BIRTH OF MRI

Diagnostic Imaging coverage in the early 1980s introduced radiologists to MRI, described its basic physics, and tracked the modality through the FDA's regulatory process and into clinical use. A high point in our coverage came in 2003 in the aftermath of the Nobel Prize for Medicine being awarded to Paul C. Lauterbur, Ph.D., and Sir Peter Mansfield but not to inventor Dr. Raymond Damadian. We interviewed Damadian to get this story and used our sources in Sweden and elsewhere in Europe to learn why he was denied the prize.

The magazine also covered the many wars of words characterizing competition over MRI's development. Dr. William Bradley, chair of radiology at the University of California, San Diego remembered the field-strength wars. High field strength enthusiasts touted the high signal-to-noise ratio of 1.5T MRI, while midfield-strength backers argued contrast-to-noise was the more pertinent measure.

Battles among equipment vendors led to stronger and faster gradients, enabling better MR angiography and body applications that arose in the early 1990s. The early 2000s are remembered for multichannel radiofrequency receiver wars touting higher and higher acceleration factors and increasing numbers of RF receiver channels, which enabled parallel imaging techniques.

There were battles over whether 3T should be established as the new gold standard for clinical high-field imaging, and a long series of articles in Diagnostic Imaging on optimizing every aspect of the modality for 3T field strength. The bore wars-a pun that Bradley probably intended-was recently fought over new ultrawide-bore scanners.

Functional MRI, the ability to indirectly map brain neural activation by measuring blood oxygenation, revolutionized neuroscience, according to Thrall. Researchers at Massachusetts General Hospital, the University of California, Los Angeles, and other institutions have been prolific in publishing fMRI studies covering everything from love to hate and the cognitive benefits of Google.

“There is a joke that fMRI made psychology into a hard science because it is reproducible and quantitative,” Thrall said.

MULTISLICE REVOLUTION

The term “revolutionary” also applies to recent experience with computed tomography. If MRI dominated the first third of Diagnostic Imaging's history, then CT has been the star for the most recent third of our run.

For Dr. Elliot Fishman, a professor of radiology and oncology at Johns Hopkins University, the multislice revolution reinvented CT at all levels. CT progressed from single- and dual-slice technologies in the 1990s through generations of four-, eight-, 16-, 64-, 128-, 256-, and 320-slice technologies that increased the modality's speed and diagnostic capabilities in steep increments through the 2000s.

The improvement wasn't just a matter of capturing the entire liver in 0.5 sec instead of 30 sec. The art of living imaging revolves around timing. With 64-slice scanning, the technologist can now capture thin slices of the liver at multiple points during the arterial and venous phases, Fishman said.

Diagnostic Imaging covered the downside of the multislice CT revolution as well. We devoted two cover stories to the risks of ionizing radiation in the early 1990s. We passed along advice about modifying system settings for pediatric CT, and covered the pros and cons of reports predicting a future cancer epidemic from the current explosive growth of the modality.

Diagnostic Imaging's coverage described the solutions to as well as the problem of ionizing radiation. We devoted coverage to the Image Gently program to educate physicians and the public about ways to eliminate unnecessary risk. And we've emphasized the importance of iterative reconstruction to maintain high image quality and reduce radiation dose.

Ultimately, MSCT is all about im-proved imaging. It acquires thin slices of the whole abdomen in seconds. The whole heart, including coronary arteries, the brain, and vascular maps of the abdomen-all once thought to be out of reach of the modality-are now possible with MSCT.

“Because of added speed and resolution, a CT scan is now like an angiographic study,” Fishman said. With fast scanning and thin-section isotropic data, every study we do is basically some sort of angiogram.”

Radiologists turned to 3D workstations, software, and volumetric imaging to deal with the unprecedented amount of information figuratively piled to the ceiling from every scan.

ULTRASOUND UPS AND DOWNS

Moore's law, the theory that the computing power of integrated circuits would double every two years into the foreseeable future, has had a greater effect on diagnostic ultrasound than on other modalities. More transistors in smaller spaces have allowed vendors to miniaturize ultrasound scanners, permitting them to be used anywhere in the hospital and by more types of medical practitioners.

More integrated circuits in the same amount of space have boosted the technical capabilities of high-performance ultrasound for diagnostic radiologists. Ultrasound images have become less user-dependent and easier to interpret because of harmonic detection, frequency compounding, and vastly improved speckle control.

Real-time 3D imaging was introduced in echocardiography and general imaging in the early 2000s. Recent innovations have revolved around electronic symmetrical focusing and beam-steering in any direction.

Volumetric ultrasound allows the radiologist to navigate the 3D images, in a way already possible with CT, to identify anatomic landmarks around areas of interest and to examine diseased tissue from several orientations.

Ultrasound elastography will soon play a role in breast imaging to differentiate the borders of spiculated masses, according to Flemming Forsberg, Ph.D, a professor of radiology at Thomas Jefferson University Medical Center in Philadelphia. Dr. Jonathan Rubin, director of ultrasound at the University of Michigan, predicts ultrasound elastography will be broadly applied to detect many types of cancer.

Still, times are tough for diagnostic ultrasound. A 2007 cover story in Diagnostic Imaging described how applications development for the modality had slowed because of FDA reluctance to grant clearance to microbubble contrast media. Its decision to issue a black box warning against contrast in the only cardiac application where it may be used in the U.S. galvanized the cardiology community, Forsberg said.

The FDA remanded the order after the American Journal of Cardiology reported on a study from the Mid-America Heart Institute in Kansas City, MO, which found that 58,000 patients who received contrast-echocardiography were 24% less likely to die in the day after the procedure than 4.2 million who underwent unenhanced ultrasound heart imaging.

Since then, the FDA has granted an application by Bracco Diagnostics to move forward with its new drug application for SonoVue, a microbubble contrast medium. A multicenter trial examining the value of enhanced ultrasound for liver lesion characterization is under way, and FDA approval could come as soon as 2011.

CRAFTY IR

Interventional radiologists have constantly needed to reinvent themselves and the technology they use in practice. By the 1990s, they had created and demonstrated the efficacy of a series of minimally invasive transluminal interventional techniques that seemed to assure their professional future.

But it was not to be. Interventional cardiologists and vascular surgeons took over those applications in peripheral vasculature, forcing interventional radiologists to develop alternative methods.

We have reported the highlights of those efforts over time. Well-established IR methods always seem to evolve into new techniques, according to Dr. David G. Dixon, an interventional radiologist at St. Luke's Hospital in Kansas City, MO. The 75-year-old Dixon was performing fluoro-guided angiography in 1977 when he learned about Dr. Andreas Grüntzig's invention of the balloon catheter. Interventional radiologists were soon using the new devices for transhepatic biliary drainages and internal stenoses. The technique was then applied to clearing arterial plaque from vessels and assisting with stent placements.

The development of image-guided RF ablative therapy was also evolutionary as it grew out of techniques for performing percutaneous biopies, Dixon said. Any mass that could be biopsied could also be ablated with RF, laser, or cryogenic probes guided by fluoroscopy, ultrasound, or MRI.

“To be a good interventionalist, you have to be knowledgeable about all the toys on the shelf,” he said.

One focus of IR practice in the 2000s migrated to nonvascular interventions as Dr. Douglas Beall built his practice in Oklahoma City.

Most of the items on Beall's menu of services did not exist when Diagnostic Imaging began covering IR. They include epidural injections, functional anesthetic discography, RF neurotomy for facet and sacroiliac joint pain, RF nerve ablation, celiac plexus neurolysis, vertebroplasty and kyphoplasty, vertebral body fusions, and placement of X-Stop spinal implants.

“We were forced to shift into these new areas,” Beall said. “It is all about survival of the fittest. Our ability to change makes us fit.”

FROM NUC MED TO MOLECULAR IMAGING

Survival and evolution are also cogent themes for nuclear medicine, another branch of the diagnostic imaging family that has reinvented itself over time. The applications of single-photon imaging grew steadily in the 1980s and 1990s, with adoption of technetium-99m as the radioisotope of choice, dual- and triple-head cameras, and attenuation-correction methods.

We covered the introduction of Tc-99m sestamibi as an alternative to thallium-201 for cardiac imaging and new analytical software that drew the interest of cardiologists who would bring stress-rest myocardial perfusion imaging into their offices.

The magazine reported the setbacks and advances that led to the acceptance of fluorine-18 fluorodeoxygluose (F-18 FDG) PET as well. We covered how lobbying efforts in Congress by the Institute for Clinical PET and the work of Sen. Ted Stevens (R-AK) forced a recalcitrant FDA to grant regulatory approval for the agent. We described the implications of PET/CT and SPECT/CT.

Dr. Henry Wagner, a professor of environmental health sciences at the Johns Hopkins School of Public Health, said the new imaging platform introduced in the early 2000s brought about a marriage between radiology and nuclear medicine.

“Combining structure from CT and function and chemistry from PET was a major breakthrough in bringing nuclear medicine to the forefront of radiology, he said.

F-18 FDG came to symbolize the promise of molecular imaging. By measuring the biochemistry of cells, FDG has also had a major impact on pharmaceutical research. Micro-SPECT and micro-PET have been widely adopted for small-animal drug research, Wagner said.

TRIUMPHANT PACS

An idea conceived by radiologists while Diagnostic Imaging was in its infancy, picture archiving and communication systems (PACS) has become a universal feature of medical imaging in the U.S. All major hospital radiology departments are equipped with PACS, according to Dr. Eliot Siegel, chief of radiology and nuclear medicine at the VA Maryland Health Care System in Baltimore. About 60% of facilities have stopped producing x-ray films, and a majority of hospitals now depend on soft-copy interpretation on workstations for all of their imaging exams.

Because of PACS, digital images are now ubiquitously available. They can be transmitted anywhere in an institution or around the world. Ultimately, images and radiology reports archived in PACS and radiology information systems will also be stored in individual patients' electronic medical records.

Radiologists are no longer passive consumers of images on film, Siegel said. With the help of volume rendering and advanced visualization techniques, they have become interactive explorers and navigators through the virtual presentation of anatomy and disease. They are joined by computers now able to help them identify the presence of cancer in digital mammography, screening CT colonography, and lung cancer exams.

On the downside, PACS has tended to isolate radiologists.

“There is the potential to marginalize the role of the radiologist as [someone who] just provides imaging interpretation, rather than full consultations,” Siegel said.

PACS also encouraged the growth of teleradiology, another major source of news and features in Diagnostic Imaging over the years. Conceived as a way to allow radiologists to handle their on-call duties from home, teleradiology evolved in a way that eliminated late-night and weekend call entirely for many practices. A new industry emerged with some organizations establishing staffs and reading stations in Australia, Europe, and the Middle East to provide nighttime preliminary reads for hospital emergency rooms in the U.S. while it is daytime where the interpretations are performed.

Recent Diagnostic Imaging coverage has tracked how the nighttime services are making a bid for daytime businesses in direct competition with local radiology groups for hospital contracts. This trend threatens to degrade image interpretation into a commodity, Dr. Alan Kaye said.

Despite this possibility, PACS and associated informatics are destined to transform imaging, Siegel said.

“Radiology is changing from an art form to a much more quantitative, structured science,” he said.

The first step is the adoption of standard lexicons and radiology reporting templates of data based on clinical and imaging experience with specific diseases and development of links to patient electronic medical records.

In this future vision of imaging practice, part of the NIH's cancer Biomedical Informatics Grid project, the radiologist will input data describing specific characteristics of a case and his or her findings. A computer will perform a quantitative analysis combining the radiologist's assessment with its own analysis of the images and data drawn from the EMR and historical imaging information.

“We will personalize clinical decisions,” Siegel said.

Radiologists will influence whatever direction this new technology takes. They have always been attracted to interesting technologies, in part because they are more socially engaged than their reputation would credit them for, Siegel said. He is not surprised that they would be among the first medical specialists to embrace the EMR, or that they would attempt to make medical imaging a part of it.

“It is a part of our culture to acquire images, to take responsibility for storing and archiving images and making sure they are safe and sound. And then it's part of our culture to make sure those images are available to share with our colleagues,” Siegel said.

Such compelling trends are essential to publishing a popular magazine. The editors and publishers of Diagnostic Imaging will take the credit for bringing accurate, relevant, and journalistically sound news and features to the medical imaging community for 30 years. But it is the imaging community itself that deserves credit for always creating interesting stories to tell.