So why, ask two experts at The Johns Hopkins Hospital in Baltimore, should we think that the imaging-based virtual autopsy, or “virtopsy,” is ready to replace the traditional direct physical inspection of the body’s internal organs?

Pathologist Elizabeth Burton, MD, deputy director of the autopsy service at Johns Hopkins, said that despite the dazzling postmortem scans depicted on such TV series as Bones and the various CSI shows:

The traditional autopsy, though less and less frequently performed, is still the gold standard for determining why and how people really died.

Dr. Burton was quoted in a Johns Hopkins news release. She and Johns Hopkins clinical fellow Mahmud Mossa-Basha, MD, state their case in an editorial in today’s edition of Annals of Internal Medicine.

A German study in the same issue shows some of virtopsy’s strengths and limitations. Among 47 people who underwent both virtual and conventional autopsies, 102 new diagnoses were found. Virtual autopsy by CT scan missed 20.8 percent of the new diagnoses, particularly air pockets in collapsed lungs (which can impede breathing) and bone fractures. Conventional autopsy missed 13.4 percent, most commonly heart attack, pulmonary emboli, and cancer.

That suggests that the best approach would be a combination of traditional autopsy with scanning. Dr. Burton agreed. “It’s not a question of either traditional autopsy or virtopsy,” she said. “It’s a question of what methods work best in determining cause of death.”

For example, she said, imaging can pick up a spot on a lung. But it can’t tell whether that spot is cancer, a fungal infection, tuberculosis-related granuloma, or a benign mass. For that, you need a physical examination.

On the other hand, a conventional autopsy without scanning might have missed that spot altogether. “Steady progress in imaging technology is refining conventional autopsy,” said Dr. Mossa-Basha, “making it better and more accurate.”

Related seminar: Imaging Advances: Abdominal, Thoracic, Skeletal

University of Pennsylvania engineers coated iron oxide nanoparticles with glycol chitosan, a sugar-based polymer that reacts to acids. The sugar keeps the particles from binding or being absorbed by the body, but this particular formulation allows them to become ionized in acidic environments and thus attracted to such areas.

Enter the Warburg effect: Most healthy cells are aerobic, getting energy primarily from oxygen, but cancer cells are anaerobic, getting energy from glucose and turning it into lactic acid. Cancer cells also disrupt the blood flow around them, making it harder for the body to clear away the acid.

So acid-attracted iron oxide nanoparticles will cluster around tumors and make them stand out on MRI images. Said Andrew Tsourkas, PhD, who did the research along with graduate student Samuel H. Crayton:

One of the reasons we like our approach is that it hits a lot of tumors; almost all tumors exhibit a change in the acidity of their microenvironment.

Dr. Tsourkas, an associate professor of bioengineering at Penn’s School of Engineering and Applied Science, was quoted in a Penn news release. The research was published in the December 27 issue of ACS Nano.

The new coating could work well for other uses too, Dr. Tsourkas said:

You can take any nanoparticle and put this coating on it, so it’s not limited to imaging by any means. You could also use it to deliver drugs to tumor sites.

It gets better: The more malignant a tumor, the more it disrupts blood vessels, and therefore the more aciditic its environment. So the new nanoparticles do a good job differentiating malignant from nonmalignant tumors.

That could particularly benefit patients getting an MRI scan as a secondary breast cancer screen. MRI’s high sensitivity but low specificity can work against it, as Dr. Tsourkas explained: “The screening detects a lot of tumors, but many of them are benign. Having a tool like ours would allow clinicians to better differentiate the benign and malignant tumors.”

That explains why the research was funded partly by the Department of Defense Breast Cancer Research Program (yes, such a thing exists).

Related seminar: CT/MRI of the Abdomen and Pelvis

More than $8 million in grants from the National Cancer Institute (part of the National Institutes of Health) are fueling the initiative. It builds on advanced imaging tools that the center has developed over the past decade.

Zaver Bhujwalla, PhD, director of the center and principal investigator for the initiative, explained in a Johns Hopkins news release the scope of the effort:

By harnessing the very latest technology in noninvasive imaging—using any single or combination imaging modality of MRI, CT, SPECT, PET, laser optics, or ultrasound—we expect to develop tests that detect cancer faster and earlier, distinguish spreading or metastatic tumors from dormant ones, and develop better and more tolerable chemotherapy drugs that only attack cancerous cells, leaving healthy cells alone.

Wow.

Here are some specific lines of investigation:

• Using MRI to find proteins or other small molecules that could represent the earliest metabolic and biological changes in the formation of breast cancer.
• Using laser imaging to analyze collagen fibers in breast cancer tumors, which form distinctive patterns in metastatic cancer.
• Using SPECT, MR scanning, and optical- or laser-guided imaging to identify cancerous prostate cells by detecting a protein found only on such cells’ outside layer.
• Using PET scans to guide a viral-activated drug, bortezomib, to kill Kaposi’s sarcoma cells.

Other research teams will explore the speed of skin cancer progression, the amount of tumor shrinkage during pancreatic cancer treatment, the process by which cancer spreads to the lungs, and treatments to prevent the spread of kidney cancer to the bones.

This could be very exciting stuff. We’ll check back to see how things progress.

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Thanks to all of you for reading us this year. We’ll keep trying to be useful, interesting, and, yes, even fun in 2012. Please continue to check us out here at Radiology Daily, on our Facebook page, and on our Twitter feed. Happy new year!

Related seminar: Abdominal & Pelvic Imaging: CT/MR/US

The study, released this week, covered providers who travel to nursing facilities, private homes, and other nonclinical locations to provide X-rays of the extremities, pelvis, spine, skull, chest, and abdomen.

The inspector general found that 20 suppliers “exhibited questionable billing patterns.” Specifically, those suppliers billed Medicare for a total of $12.8 million for return trips to nursing facilities on the same day. Those payments may or may not have been legitimate. As the study said, “Claims data do not provide sufficient information to determine whether the supplier billed correctly for two separate trips to the facility or whether the supplier administered tests to the two beneficiaries during a single trip and incorrectly claimed full reimbursement of the transportation component for each beneficiary.”

The study found another $6.6 million in clearly incorrect payments. Medicare covers portable X-ray services only if they were ordered by a physician. The study found $4.3 million in payments for X-rays ordered by nurse practitioners, $1 million ordered by physician assistants, $900,000 ordered by podiatrists, and $400,000 ordered by registered nurses, chiropractors, and other nonphysicians.

The inspector general suggested that Medicare tighten its procedures, follow up on the questionable payments, and collect the $6.6 million in overpayments. The Centers for Medicare and Medicaid Services agreed.

So our government is trying to be more efficient and root out fraud. We applaud that. But couldn’t the inspector general more effectively use its resources by going after bigger fish?

Don’t get us wrong; we’re not in any way endorsing fraud or errors in Medicare payments. But Medicare paid about $225 million for portable X-ray services in 2009—out of total Medicare payments of $454 billion. That’s about five hundredths of 1 percent. Of the 352 suppliers of portable X-ray services that the inspector general studied, it found possible billing problems with only 20.

Frankly, this report seems to be, if anything, a vindication of the portable X-ray industry. When it comes to billing practices, the vast majority of suppliers seem to be following the rules.

Related seminar: Imaging Advances: Abdominal, Thoracic, Skeletal

Breast-cancer researcher Mina Bissell, PhD, explained:

Our data show that at lower doses of ionizing radiation, DNA repair mechanisms work better than at higher doses. This nonlinear DNA damage response casts doubt on the general assumption that any amount of ionizing radiation is harmful and additive.

Dr. Bissell, who holds the title of distinguished scientist at the Berkeley Lab’s Life Sciences Division, was quoted in a lab news release. The findings have particular significance for those who undergo such low-dose medical imaging procedures as mammograms.

The lab revealed the results of its research in a freely available study published online Monday in Proceedings of the National Academy of Sciences.

The decreased risk at low doses derives not from the amount of damage caused by the radiation but rather from how the body fixes the damage. The researchers found that after low doses of radiation, the body repairs double-strand DNA breaks (meaning the double helix is completely severed) on site. It’s a relatively simple procedure with relatively little chance of error.

But as doses increase, creating more double-strand breaks, the broken strands congregate at “radiation-induced foci” (RIF), which are aggregations of repair proteins. With lots of repairs going on at once, the opportunities for mistakes increase.

“We hypothesize that, contrary to what has long been thought, double-strand breaks are not static entities but will rapidly cluster into preferred regions of the nucleus we call DNA repair centers as radiation exposure increases,” said Sylvain Costes, PhD, a biophysicist who led the study.

“As a result of this clustering,” Dr. Costes said, “a single RIF may reflect a center where multiple double-strand breaks are rejoined. Such multiple repair activity increases the risks of broken DNA strands being incorrectly rejoined, and that can lead to cancer.”

The researchers are looking into whether their results, achieved with a single human breast cell line, will hold up with different lines and different breast cells. Stay tuned.

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MRI powers a tiny wireless camera that navigates the digestive system. Science fiction? Find out on our Facebook page.

Related seminar: ALARA — CT (As Low As Reasonably Achievable)

The Wall Street Journal reported Friday that the Indianapolis-based company, which insures about 34 million people, will cover the scans for those who match the characteristics of participants in the National Lung Screening Trial.

As we’ve mentioned a couple of times, the trial found such positive results from screening with low-dose helical CT lung scans—a 20 percent lower risk of dying from lung cancer compared to screening with standard chest X-rays—that the National Cancer Institute stopped the trial early.

So WellPoint will cover those who have smoked at least the equivalent of a pack a day for 30 years, are 55 to 74 years old, and, if they’ve quit smoking, did so within the past 15 years.

John Whitney, MD, a WellPoint medical director, told the Journal:

This was the first time a really well-done study showed you could save lives by screening with this technique.

However, because of such “potential downsides” as the risk of false positives and the extra radiation dosages from the CT scans, Dr. Whitney said, “We think the evidence only supports screening for the population they studied and showed a benefit in.”

For now, WellPoint will cover annual scans for three years, again closely following the study.

Also for now, no other insurers seem to be following WellPoint’s lead. Cigna, Aetna, and UnitedHealth Group all did tell the Journal they were keeping an eye on the issue.

A lot of medical institutions, ranging from big hospitals to storefront clinics, have been promoting CT lung scans because, of course, they see potential profits. And WellPoint, of course, sees potential savings for itself if the scans can find cancer early enough that it can be treated relatively inexpensively.

Maybe everybody’s right and patients will benefit too. Wouldn’t that be lovely?

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We can’t promise that today’s Facebook post will be lovely, but we’ll do our best to make it interesting.

Related seminar: Cardiovascular & Pulmonary Imaging

B.C. Wang, PhD, studies molecules. (He’s Ramsey-Georgia Research Alliance Eminent Scholar in Structural Biology at the University of Georgia in Athens). X-ray crystallography—bombarding molecules’ crystalline forms with X-rays—reveals the position of chemical bonds and other important properties.

However, large molecules, which are especially important in drug development, don’t handle X-rays as well as small molecules do. In a University of Georgia news release, Dr. Wang explained:

A macromolecular crystal can only withstand a certain amount of X-ray dose before it is destroyed as a result of radiation damage. Obtaining accurate and complete diffraction data sets of these crystals is very important.

So Dr. Wang and his team tried doing several low-power scans of the same crystals (specifically, bovine insulin crystals) instead of a single higher-power scan. The weaker scans delivered the same total radiation dose as the single higher-power scan would have. They also produced much better data than the single scan. For details, see the study, published online this month (open access) in the journal Foundations of Crystallography.

Adapting this technique to human imaging could produce better-quality scans while reducing radiation exposure, though Dr. Wang cautions that such applications will not be ready for clinical use anytime soon.

Of course, there will be problems to overcome. For one thing, bovine insulin molecules are generally better at holding still than people are. And Dr. Wang’s team uses X-ray data in a different form from the familiar human X-ray image. But, obviously, such multislice technologies as CT have overcome similar issues.

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Follow us on Twitter, and we’ll feed you a handful of carefully chosen radiology-related morsels each week that we think you’ll find interesting, or at least amusing.

Related seminar: ALARA-CT (As Low As Reasonably Achievable) (free shipping ends tomorrow!)

It comes from the Medical Imaging & Technology Alliance (MITA), a trade group for makers of medical imaging equipment. So perhaps it’s not so surprising.

MITA said in a Wednesday news release that, according to its own analysis of Medicare data, spending on imaging for each Medicare beneficiary has decreased 13.2 percent since 2006. In addition, the release said, imaging utilization per beneficiary decreased by 3 percent in 2010. Spending for Medicare services other than imaging has increased by 20 percent since 2006, and overall utilization increased by 2 percent in 2010, MITA said.

David Fisher, MITA’s executive director, said the reduction in imaging spending and use may be harming Medicare patients:

It is unsettling to see these accelerating declines in Medicare beneficiaries’ use of medical imaging services during a time of tremendous advances in imaging and radiation therapy technologies, which have become increasingly integral to medical best practices and early disease detection. This disconnect raises serious concerns about whether or not patients are receiving the care they need.

Somehow, we can’t see the congressional “super committee” bursting out of its phone booth, or its locked meeting room, or wherever it’s been thrashing out deficit-reduction proposals, and saying, “Sure, cut spending on Social Security, the military, our salaries, and everything else, but we really need to increase Medicare spending on imaging.”

Still, as MITA points out, imaging reimbursements have been cut seven times in six years, with payments for such services as bone density screenings, arm and leg artery X-rays, and brain MRI reduced by more than 60 percent. And further cuts have been proposed. Are Medicare patients in fact now getting second-rate care … well, maybe that’s too strong; let’s say suboptimal care in terms of imaging?

MITA also quotes John A. Patti, MD, chair of the American College of Radiology Board of Chancellors, as saying, “Current evidence, including this analysis, debunks the myth that imaging is significantly overused and somehow responsible for escalating health-care costs.”

Dr. Patti adds:

According to these data, the goal of bending the cost curve has indeed been achieved for medical imaging. Any further reductions would represent socially irresponsible policy.

Of course, the fact that a piece of legislation might be socially irresponsible has never stopped Congress before.

Related seminar: Radiology Review Course

CSX Transportation, the target of thousands of lawsuits over the years alleging that it exposed employees to lung-damaging asbestos, has turned the tables and sued Dr. Harron and three Pittsburgh lawyers.

The lawyers filed thousands of asbestos lawsuits in West Virginia courts. Dr. Harron, according to a pair of New York Times articles in 2005 and 2007, provided X-ray readings and written medical reports backing claims of asbestos-caused lung damage filed on behalf of more than 88,000 people.

According to the Times, Dr. Harron ended his regular radiology practice in the mid-1990s and began reading compensation-case X-rays full-time. The paper said he read as many as 150 a day, charging $125 for each report he produced.

In 2005, Dr. Harron supplied diagnoses of silicosis, a lung disease caused by exposure to silica, in a federal trial in Texas. Federal District Court Judge Janis Graham Jack found that Dr. Harron’s diagnoses did not rely on physical examinations, as the reports under his name claimed, but rather on X-rays and medical histories taken by law firms or screening companies (which set up X-ray screenings to look for silicosis victims and which were not staffed by doctors).

Jack made a more damaging charge: “When Dr. Harron first examined 1,807 plaintiff’s X-rays for asbestos litigation, he found them all to be consistent only with asbestosis and not with silicosis.” But after reexamining X-rays of the same 1,807 people “for silica litigation, Dr. Harron found evidence of silicosis in every case.”

It’s rare that one person would develop both diseases. The judge, a former nurse, concluded that the diagnoses “were manufactured for money.” She wrote:

The record does not reveal who originally devised this scheme, but it is clear that the lawyers, doctors and screening companies were all willing participants.

Now, CSX is taking aim at Dr. Harron. The Record, a West Virginia legal journal, reported that CSX filed a complaint in October alleging that Dr. Harron had supplied fraudulent asbestosis diagnoses. It said Dr. Harron had lost his medical license in seven states and had invoked his Fifth Amendment privilege against self-incrimination 392 times in a deposition and once before a congressional subcommittee.

On November 7, a lawyer for Dr. Harron, Jerald Jones, responded with a court filing saying that Judge Jack’s allegations were false and that CSX’s complaint had slandered and defamed Dr. Harron. Jones wrote:

All and each of the allegations and statements made by the plaintiff are false, maliciouis, and untrue.

Regarding Dr. Harron’s loss of his medical license in seven states, Jones wrote that “the cause was Judge Jack, not misconduct, as no misconduct was ever established.” Regarding the invoking of the Fifth Amendment, Jones wrote that Dr. Harron did so on the advice of a lawyer.

All we can say is: what a mess.

Related seminar: Cardiovascular & Pulmonary Imaging

Interestingly, the study found that electronic health information exchange (HIE) use increased some types of imaging, notably chest X-rays.

Mark Frisse, MD, professor of biomedical informatics at Vanderbilt University Medical Center in Nashville, led the study. A Vanderbilt news release quoted him as saying:

This is the first study to show that, on a citywide basis, investments in technology can save medical costs by improving care. We took the ‘Tennessee simple’ approach and built a low-cost system that said, ‘Folks, if you do it simply and build it up, doing the right thing can save you money.’

ED physicians used the system, accessed through a secure Web portal, only when they thought it might be useful—which turned out to be 6.8 percent of the time.

Eleven EDs had full electronic access. The 12th did not until the very end of the study period. That hospital, which was the busiest (20 percent of total regional ED visits), relied on printed-out summaries and could inquire for more complete data. The study calls this the “mixed-access group.”

The 13-month study compared nine outcomes: ED-originated hospital admissions, admissions for observation, lab tests, head and body CT scans, ankle and chest X-rays, outpatient surgery, and echocardiograms. Each HIE-use patient was matched with a similar patient for whom doctors did not use the HIE.

Decreased admissions for the HIE-access cases over the 13 months saved $2,059,588, according to the study. CT scans also decreased, but not uniformly. At full-access EDs, head CTs and chest X-rays increased while body CTs and lab tests stayed flat. At the mixed-access hospital, head and body CTs and lab tests decreased while chest X-rays stayed flat.

The study (which is open-access) doesn’t comment on those differences except to say: “We speculate that the small but significant increase in chest X-ray use in inner-city ED within the direct access group is an example of differences in provider motivation.” Knowing the patient population each hospital serves would probably be enlightening, but the study does not identify the hospitals.

Patients could opt out of HIE participation, but only 1 percent to 3 percent did. Dr. Frisse said the system safeguards patient privacy. “It makes available only the information you choose, and it can only be used when you are needing care,” he said. “It is far more secure and useful than paper.”

He is definitely an enthusiast:

Our people believe that the savings from this study are less than 2 percent of the overall savings these technologies can afford if every physician’s office is connected. And we are absolutely convinced and committed to extending this approach to every health care setting.

Related seminar: National Diagnostic Imaging Symposium™