GIGO applies here, but with much greater consequences. Conversely, good information in results in more valuable consultation out in the form of the Radiology reports. See this article for how the authors “found improvement in quality of histories provided on requisitions for unenhanced head CT after a fairly simple intervention in the ED. In addition to aiding interpretation, improved clinical information significantly reduced time in receiving payment for the studies.” This results in a “win” for all, including likely improved quality of care for patients.
This article goes straight to the heart of the challenge of tailoring care to each individual patient. Such a tailoring challenge bumps up against algorithmic appropriateness analyses, particularly those which are computerized for decision support. Generalized appropriateness may not ideally apply to individual patients and their unique situations.
How we balance these challenges is to be worked out – to fail at this challenge would be to compromise care, both overall and individually. The coming 5 years will be very interesting for this balance.
The American College of Radiology’s (ACR) CT Dose Index Registry (DIR) program was introduced in May 2011. The DIR is a data registry that allows institutions across the United States to send their anonymized CT exam dose information to the ACR to be saved in a database at ACR. Institutions are then provided with semi-annual feedback reports comparing their results by body part and exam type to aggregate results for adult and pediatric exams. Facilities can then compare their CT dose indices to regional and national values.
At UW, we enrolled in the DIR in May 2011 and since then have been sending encrypted DICOM structured dose report files from all of our CT scanners to ACR. Doing so required collaboration between ACR, IT, PACS personnel and the on-site physicist. Implementation involved several challenges, including software installation and data transmission consistency problems. Since numerous institutions are involved, the ACR required an exam mapping process via the Radlex Playbook to unify the protocol classification. This mapping process has been the most challenging factor in the implementation process. These challenges have been overcome and data is being successfully transmitted to and analyzed by the ACR.
The first report comparing adult patient dose data (CTDI and DLP by medical examination and by scan) between our site and others around the region and country was made available in January 2012 and the second one in September 2012. For each exam, the report includes box-plots and histogram data for a variety of standard protocols. The second report estimated the size specific dose estimate from the scout for each patient exam.
The ACR CT Dose Index Registry program has been very successful and is a useful tool for dose data mining and will eventually establish national benchmarks for CT dose indices.
For more information on the Registry, please see this article here!
According to a new study based on the International Early Lung Cancer Action Program (I-ELCAP), lung cancers identified in low-dose CT screening programs are similar to those identified by non- screening means. The research results, which were released on March 27 in Radiology, further alleviate concerns that cancers detected through low- dose CT screening are less aggressive than those found through other means, and therefore demand less attention and resources. In fact, the frequency of small-cell carcinoma and adenocarcinoma were similar for cancers detected through screening programs and outside the screening setting.
This study is another brick in the wall of evidence building for the value of low radiation dose CT lung cancer screening in high risk asymptomatic smokers. Regardless of whether nodules are solid or “ground glass” (non-solid), growth occurs that is similar in the screened populations and in those detected of having lung cancer due to symptoms.
While it is true we do not yet have a data-based analysis of costs versus quality life years saved, the evidence that screening is worthwhile continues to become stronger. “The CT scanners we have now are really phenomenal,” with resolution that continues to improve as the radiation dose falls, “so that the amount of information you can get out of them for emphysema, for coronary artery risks, and so on, continues to increase,” says Dr. Claudia Henschke, lead author of this study.
She goes on to point out that cancers detected via low dose CT screening “are real cancers that would kill you if they weren’t discovered early, so it kind of underscores again the data that we had shown in ELCAP and that NLST (National Lung Screening Trial) has shown — that screening for lung cancer saves lives.” And that is the key takeaway.
I recently came across a study that questioned the cost- effectiveness of low-dose CT scans for lung cancer screening. As I’ve discussed before, there is sufficient and sound research validating that among high- risk individuals, low-dose lung cancer screening is a life saving process. However, this article claims that the medical imaging procedures may be too costly for the United States, “a nation struggling to control growing health care costs, even though some lives would be saved.”
This article clearly shows how charges relate to the execution of healthcare. At standard charges, screening CT of patient’s at high risk for lung cancer may not be cost effective. But, if these are regarded as add-on incremental cases and are priced at marginal cost (approximately $200), the screening equation may change and become financially viable from society’s prospective.
As with any screening program, the first caveat is to “do no harm” – hence an ultra-low dose CT technique would be advantageous. Similarly, figuring out how to keep the cost way down will be critical. I think we can….
If you work in radiology, chances are that you are aware of the Image Wisely campaign. Created by the Joint Task Force on Adult Radiation Protection (made up of members of the American College of Radiology and the Radiological Society of North America), the American Association of Physicists in Medicine (AAPM), and the American Society of Radiologic Technologists (ASRT), the campaign strives to lower the amount of radiation used in medically necessary imaging studies and to eliminate unnecessary procedures.
I am proud to say that I have taken the pledge, with over 12,000 other health care professionals, to image wisely by optimizing the use of radiation when imaging patients.
The Image Wisely campaign is a very impactful undertaking which deserves the attention and participation from all of us in Radiology. The pledge raises awareness and commitment to maximizing the ratio between information obtained for minimal dose utilization. In addition, the pledge assists with low dose protocols and good practices, plus equipment operation is included.
I urge all to read the website closely and understand the goals of the campaign. Then take the pledge today!
Recently, the National Comprehensive Cancer Network has come forward in favor of lung cancer screening with low-dose CT. The NCCN is the first professional organization to perform the comprehensive review and update their recommendations to promote lung cancer screening.
This update further validates the key concept that high risk patients benefit from screening. High risk patients for lung cancer diagnoses are those who are multiple pack year smokers for 25 of more years. For these individuals, low- dose CT screening reduces the number of lung cancer deaths by 20 percent.
While we don’t really know the full cost of a screening program – such as the costs of working up false positive CT findings, the benefit in lives saved seems to justify considering screening now.
Fortunately, the CT technique for screening is low dose and involves low radiation dosage.
RSNA (Radiological Society of North America) is the largest annual trade show in the world, with about 55,000 people in attendance for the 6 day event in Chicago, Illinois. The expo includes a large number of presentations and courses on science and modern radiology.
RSNA 2011’s two main themes were lower radiation dose in diagnostic radiology imaging (especially CT) and new technology. For lower dose, there was much material on tailoring a CT scan exactly to an individual patient – based on their body size, their cardiac output, their disease process, or the type of diagnostic challenge. Additionally, a lot about new iterative reconstructions in CT – both statistical and model based, was presented. Either method lowers dose a lot, but model based results in lowered radiation exposure by up to 80%.
New technology presentations and courses covered a range of topics including dual energy CT for better tissue characterization, and the combination of imaging modalities in one platform – like SPECT/CT, or PET/MR. These combined modalities may provide a better combination of disease identification plus precise localization.
In all, RSNA 2011 offered great insights and interesting presentations. Did you attend? Share your thoughts below!
A recent presentation at the 2011 International Society for Computer Topography (ISCT) meeting in San Francisco highlighted the effectiveness of using dual- energy CT for abdominal imaging. This CT- technique has become more promising for uncovering certain pathology that has otherwise been hidden by traditional diagnostic imaging procedures.
Dual- energy CT- by whatever technology – can be configured to employ less radiation than single energy CT. But for some specific applications, it produces more diagnostic and specific information. Dual- energy CT currently may be the best radiology technique for characterizing urinary tract stones to their chemical composition (which determines whether medical, shockwave, or laser therapy will be required), characterizing small renal masses, and characterizing liver masses into cyst versus tumor.
Additionally, dual- energy CT may apply to better detecting minimal liver tumors, lowering the amount of iodine needed for CT angiograms, and creating virtual non- contrast scans. The latter may reduce the overall CT radiation dose of a multi- phase study by 20 to 50 percent!
While dual- energy is still relatively new to the field, it is clear that it is a promising technique for CT dose reduction, while maintaining imaging quality. Further research and testing will be conclusive of the absolute benefits of dual- energy CT.
The RSNA 2011 conference marks the 97th Scientific Assembly and Annual Meeting. This event, the world’s premier medical meeting for radiologic professionals, is being held on November 27 through December 2 at the McCormick Place in Chicago. The annual conference includes unparalleled education and professional development, networking opportunities, and a cutting- edge technical exhibition.
I will be involved in a number of events, both as a presenter and an author. The presentations that I will be involved in include:
• Presenter- Hot Topics: Dual- Energy CT on Tuesday, November 29 from 7:15 am to 8:15 am.
• Presenter- Refresher: Mind Your Own Business! Required Business Skills for Your First Job on Thursday, December 1 from 4:30 pm- 6:00 pm.
• Author/ Participant- Gastrointestinal Series: Scientific Formal Presentation (Dual-Energy CT of Hypervascular Liver Lesions: Evaluation of Lesion Contrast-to-Noise with Different Monochromatic keV Reconstructed Images) on Monday, November 28 from 9:50 am to 10:00 am.
• Author/ Participant- ISP- Health Services, Policy, and Research- Scientific Formal Presentation (Patient Knowledge and Perceptions about Radiation from Diagnostic Imaging) on Monday, November 28 from 3:30 pm to 3:40 pm.
• Author/ Participant- Neuroradiology Series: Stroke Imaging- Scientific Formal Presentation (Changes in the Measured Size of Atherosclerotic Plaque Calcifications in Dual-Energy CT of ex Vivo Carotid Endarterectomy Specimens: The Affect of Different Monochromatic keV Image Reconstructions) on Wednesday, November 30 from 11:00 am to 11:10 am.
For more information about RSNA 2011 and the presentations that I’ll be involved in, please see the meeting program.
A new study published in the March issue of the Journal of the American College of Radiology shows that the use of virtual colonoscopies at U.S. hospitals is increasing – even though the procedure is not covered by Medicare.
A neat feat of virtual colonoscopy is how the radiation dose associated with the exam has dropped considerably since it was introduced. Newer reconstruction techniques on newer CT scanners have made this possible.
While it is still true that Medicare will not pay for any type of screening (except mammography), some commercial insurance companies have realized the value of screening for colon cancer, particularly in high-risk patients. Screen CT colonography does well when compared to other tests for detecting colon tumors and polyps. And patient acceptance is higher because it is quick and less uncomfortable.
…for dead people.
Check out this interesting story, “Radiology Helps Unwrap Mummy Mystery,” about a radiology lab helping out a university museum with some mummy research. They were hoping that, through the use of CT scans, they’d learn some valuable information about the mummy and the person he once was.
What caught my eye was this quote: “Radiation protection is very important in living humans…but this concern was completely inapplicable to this situation. So we were able to do two things: we were able to use a much higher radiation dose and also use much thinner slices than we would typically use on living patients to examine them.”
Amusing, isn’t it? Dead people are willing to pay the price for images that look too good: high radiation.
One of the most common complaints of patients in the ER is abdominal pain, and as a recent article at TIME.com details, diagnosis is rarely straightforward. It is important to understand that the ER is different from other places where healthcare is provided. ER physicians see a broad spectrum of disease – from the insignificant to the life-threatening. There are great time constraints in the ER, as well, and follow-up care is hard to arrange (and may be unreliable) so there is pressure for a definitive diagnosis in a single encounter.
Physicians considering the CT scan to assist with diagnosis for abdominal pain or other illness and injuries should consider three questions:
1. Is CT the right test to do for this patient?
Many ER physicians are good at a answering this question, but it is also helpful to remember that the best expert on appropriate use is one phone call away: the radiologist. Having the patient’s EMR handy is important, too, in reporting how many CT scans this patient may have had historically, since this is a data-point in choosing whether or not to do CT. A national registry of individual patient cumulative radiation dose is coming to the U.S., similar to the one that now exists in the EEU, but it is not here yet.
2. If CT is the right test, what kind of CT?
With contrast or without? Oral contrast or not? Positive oral contrast or negative? One pass or three? Arterial or portal venous phase? Abdomen only or abdomen plus pelvis? Again, the radiologist is a valuable consultant for getting the most information about the patient’s condition at the least radiation cost.
3. How can the CT scan be done with the lowest possible radiation dose?
Finally, once the kind of CT exam is decided, how can it be done with the lowest possible radiation dose without compromising the diagnostic value of the scan. A well-informed radiologist can reduce the radiation dose per scan by up to 60 percent. For example, CT of the urinary tract with contrast now can be achieved in a single pass. Careful attention to CT imaging parameters can radically lower dose (low kVp, modulated mA, etc.). Limiting the length of the scan on the patient and careful centering of the patient by the tech can greatly reduce dose. In addition, newer scanners combine better detectors with more complex reconstruction algorithms to substantially lower dose and CT scan radiation risks.