Contrast Material Injection Can Be Reduced in Elderly Patients
A study conducted by the Department of Technical Radiology at the Nagoya University School of Health Science, Nagoya, Japan, found that the dose of contrast material for elderly patients can be effectively reduced by at least 10% for multidetector CT (MDCT) examinations of the pancreas and biliary regions.
The report, which appeared in the August 2006 edition of the American Journal of Roentgenology,1 assessed 112 patients ranging from 23 to 80 years of age who had known or suspected pancreatobiliary disease, divided into three groups. Group 1 included patients aged 60 or younger whose contrast injection was 0.08 mL/kg/s; Group 2 included patients older than 60 whose contrast injection was 0.08 mL/kg/s; and Group 3 included patients older than 60 with a contrast injection of 0.07 mL/kg/s.
According to the study, “When interpreting CT images acquired using [standard contrast injection] protocol in our clinical practice, we noted that in some examinations of elderly patients, because contrast enhancement of the pancreatic parenchyma in pancreatic phase images was too intense, the standard settings for window width and level used at our institution had to be adjusted to evaluate the parenchyma in detail.”
Contrast enhancement in the aorta, portal venous system, pancreas, and liver was assessed quantitatively. Two radiologists, who were unaware of the patients’ clinical information or the injection protocol used to acquire the CT images, ranked the degree of contrast enhancement on a scale of 1 to 5; the results for different age groups were then statistically compared.
Researchers used a 16-slice Aquilion CT from Toshiba America Medical Systems, Tustin, Calif. Nonionic contrast material with an iodine concentration of 300 mg I/mL was injected at a fixed duration of 30 seconds, and a 5% dextrose flush was injected at a fixed rate of 5 mL/s over 6 seconds immediately following contrast material injection. The injection rate was reduced by 10% for Group 3.
The two radiologists assessed and ranked the images based on specific clinical criteria. For example, in arterial phase scanning, the reviewers assessed whether the images were suitable for delineating the peripancreatic arteries; they also identified images in which arterial enhancement was sufficiently high and in which pancreatic and portal venous assessment was low. In pancreatic phase scanning, the reviewers looked at whether the images were suitable for delineating the pancreatic and bile ducts and detecting pancreatic carcinomas by achieving “intense and homogeneous” enhancement of the pancreatic parenchyma.
Compared with Groups 1 and 2, Group 3 effectively achieved an effective 12.2% reduction in the volume and rate of contrast material injection. In the discussion portion of the report, researchers note that increasing the amount of injected contrast material results in higher costs and a greater risk of complications like renal dysfunction and extravasation, providing dual incentives for administering contrast material at a specific volume and rate.
“In conclusion,” the researchers write in the study, “we recommend reducing the dose and rate of contrast material injection by at least 10% in patients more than 60 years old for multiphase contrast-enhanced CT studies of the pancreatobiliary region with an MDCT scanner. It should be noted that this helps to reduce both the cost of the examination and the risk of complications.”
Reference
Itoh S, Ikeda M, Satake H, Ota T, Ishigaki T. The effect of patient age on contrast enhancement during CT of the pancreatobiliary region. AJR Am J Roentgenol. 2006;187:505–510. Available at: www.ajronline.org/cgi/content/abstract/187/2/505. Accessed October 20, 2006.
Retrospective Study Shows Obesity Affects Image Quality
A study conducted by Uppot et al showed a significant difference between the weight of patients with habitus-limited reports and the weight of patients with reports that were not habitus limited, suggesting that obesity has an adverse affect on image quality. The study was performed retrospectively by searching radiology reports from 1989 to 2003 for the phrase “limited due to body habitus.” Trends in the number of such reports were calculated for every year, and linear regression analysis was performed. The number of habitus-limited reports corresponds with the average prevalence of obesity in Massachusetts over time, providing further evidence that the limitation arose from patient weight and not other related factors.
Overall, 0.15% of reports identified between 1989 and 2003 were habitus-limited, with the average age of patients at 57.1; female patients accounted for 65.2% of reports, male patients 34.8%. The average weight of 200 randomly selected habitus-limited patients was 239 pounds, whereas the average weight of 200 randomly selected patients was only 162 pounds. Further independent-samples tests showed a significant difference between the weights of patients in the two groups.
The study, published in the August issue of Radiology, also notes an evident trend toward more habitus-limited reports, with the percentage increasing from 0.10% in 1989 to 0.19% of all reports by 2003. The modality most frequently limited by habitus was abdominal ultrasound, followed by chest radiography, abdominal radiography, abdominal CT, chest CT, and MRI.
The report explains that although the number of habitus-limited reports is relatively small, radiologists are increasingly challenged with accommodating obese patients on standard CT or MR imaging tables, particularly with the growing number of gastric bypass surgeries. “At our institution, all of these patients undergo postoperative contrast-material–enhanced imaging to ensure there are no anastomotic leaks. The weight of these patients can exceed the weight limit of the fluoroscopy table. In this case, the examination is limited to obtaining poor-quality serial chest and abdominal conventional radiographs.”
Improve MRI Safety in Existing Facilities
By Tobias Gilk
The past few years have brought an increasing awareness of both patient and staff safety in the MRI suite. The labeling standards set forth by both the American Society for Testing and Materials [ASTM International], West Conshohocken, Pa, and the FDA, Rockville, Md; the American College of Radiology’s White Paper on MR Safety; and hosts of new products and educational programs are dedicated to enhancing safety in this part of the hospital. These new resources are great for planned facilities, but what about for existing MR suites?
Some imaging providers decided that operational MRI equipment, vital to daily clinical and financial needs, cannot be shut down to accommodate safety improvements. This assumes, wrongly in many cases, that there is no penalty for inaction.
With sufficient patient volumes, an MRI should generate roughly $1,000 per hour of operation. An incident that interrupts a day of scanning will cost a facility $10,000 to $12,000 in lost revenue. Add in vendor services, plus equipment damage, and damages from a small accident can rapidly approach a six-figure price tag. An accident in 2005 in which a floor polisher was “sucked” into an MRI in Seattle cost the hospital more than $200,000. These sorts of major missile-event accidents may be occurring with an average frequency of once every 5 years for every MRI, and many indicators are pointing to rising rates of these and other types of MRI accidents.
Short of knocking down an existing facility and starting over, what is an MRI provider to do to improve safety—and reduce the associated financial risks?
Evaluate existing patient screening protocols, both for clinical screening of contraindicated implants or foreign bodies and for physical screening for carried or worn ferromagnetic materials. One academic medical center discovered that half of its successfully screened patients were later found to have ferromagnetic materials on their person! Reconsider where and how these screenings are now done and how you might improve on those processes.
Consider the use of ferromagnetic detection systems. Unlike conventional airport-style detectors, this new breed of devices has been specifically designed to be used for screening MRI patients and will not alarm on metals generally safe in the magnet room, such as aluminum or nonferrous stainless steel. These are available in many different formats, from zone detectors to walk-through portals to handheld detectors, all with differing levels of sensitivity. Retrofitting these new products in an existing MRI suite often requires little more than an outlet.
Observe how people and objects enter the areas near the magnet room. What means do you have of limiting access, even restricting untrained facility staff? Sixteen layers of security and screening for patients are of limited value if untrained housekeeping staff can enter the department unsupervised and wander freely. Sometimes, this requires nothing more than installing a lock and a closer on an existing door.
Dozens of other considerations contribute to improving safety in MRI suites. One of the best resources to help identify many of these is the ACR White Paper on MR Safety,1 an updated version of which is due to be published soon. Although there are costs involved, facilities without the time or resources to conduct in-house evaluations may be well advised to invest in the advice of experts in MRI safety and suite planning.
Ultimately, improving safety is about improving your processes. This can lead to many unintended benefits, such as greater patient satisfaction and enhanced throughput, making an even stronger case for improving safety in existing MRI facilities.
Tobias Gilk is an associate architect for Junk Architects, Kansas City, Mo, which specializes in MRI suite planning and consulting. He also is an editor of the MRI Newsletter (www.mri-planning.com) and a member of the American College of Radiology’s MR Safety Committee.
New Census Shows Double-Digit Growth in PET Patient Studies
A recent report released by the Medical Information Division of IMV Ltd, Des Plaines, Ill, shows steep growth in PET studies. The census shows that approximately 1,129,900 clinical PET patient studies were performed in the United States in 2005 at 1,725 hospital and nonhospital sites; technology used includes dedicated PET/CT or PET scanners, mobile PET/CT or PET scanners, and nuclear medicine cameras with coincidence detection.
“The PET imaging market is experiencing double-digit growth, with studies increasing 60% from 706,100 patient studies in 2003, for an average annual growth rate of 26.5% over the 2-year period,” Lorna Young, senior director of market research at IMV, summarized in a press release. “PET/CT scanners have become the preferred technology for PET imaging, as the integration of the functional PET images with the anatomical visualization of CT has allowed more accurate and faster diagnosis. Although the proportion of PET/CT scanners versus PET scanners installed to date is about 55%, more than 90% of the units installed in 2005 were PET/CT scanners.”
The report charts trends in PET and PET/CT patient studies by procedure type, PET and PET/CT installed base by manufacturer and year of installation, planned purchases, radiopharmaceutical utilization and expenditures by supplier, and site operations characteristics.
“PET imaging is still relatively new,” Young said, “and sites are developing experience with PET imaging. While 1,725 sites offer PET imaging, nearly 1,000 of these sites use a mobile service provider, typically for 1 to 2 days per week, and 735 sites own one or more fixed PET or PET/CT scanners.”
The report’s other key findings include:
of the studies performed on PET or PET/CT scanners, 93% are for oncology applications, with the other 7% representing cardiology and neurology applications;
nonhospital locations account for 60% of all fixed PET or PET/CT scanners, while 40% are installed in hospitals; and
the five states with the highest PET study volume are California, Florida, Texas, New York, and Pennsylvania.
The full report is available along with the license to access IMV’s database of PET imaging information, or it can be purchased separately at www.imvlimited.com/mid.
—C. Vasko
Imaging Career Tracks: The Art of Administration
Building a network and other secrets to success from Roberta M. Edge, the AHRA’s 2006 Gold Award winner
By Dana Hinesly
Roberta M. Edge, CRA, FAHRA
The American Healthcare Radiology Administrators (AHRA), Sudbury, Mass, recognized Roberta M. Edge, CRA, FAHRA, with its 2006 Gold Award. An AHRA member for almost 2 decades, Edge is currently the director of imaging services at Sutter Gould Medical Foundation, Modesto, Calif. In a conversation with Axis Imaging News, she attributes much of the success in her career to her active participation in the organization, and identifies which qualities are most valuable in an administrator and what challenges face today’s imaging professionals.
IE: In earning the Gold Award, you have been acknowledged for making significant contributions to the profession of imaging and health care administration. Is there any one contribution of which you are most proud?
Edge: I am most proud of the writing I do, because I think it’s important that when people become seasoned in their profession, they pass on that knowledge. I’ve written, I’ve peer-reviewed articles on radiology management, and I’m also authoring some chapters in a series of textbooks that AHRA is developing for the CRA program. One of the things AHRA is committed to is passing knowledge on to future radiology administrators, which is why they created the Imaging Leadership Institute.
IE: What are some of the biggest changes that you have seen over the course of your career?
Edge: The business has changed, and expectations for people in these positions have changed. I would say that the vast majority of people who are in director and administrator roles were technologists first, which means we had science as the basis of our careers, not business backgrounds. When I had my first director’s job, people assumed I knew things because I had the title, and I found I didn’t know things that I felt I should have known. That’s when I went back and earned a master’s degree in health administration, which a lot of us are doing. The AHRA developed the CRA to help close that gap. The certification demonstrates that an individual has the minimum skills required to be a radiology director or administrator.
IE: What are some of the business responsibilities facing imaging directors now that they did not have to deal with in the past?
Edge: I think the largest change has been in the financial arena: handling budgets, negotiating contracts with vendors, and asset management—all of the things that fold into the financial responsibility of the position.
IE: How important has membership in the AHRA been to the development of your own career?
Edge: It’s pretty much been the lifeline. The AHRA membership has allowed me to network with people I never would have met otherwise. I became actively involved in 1994 as a membership chair for the Western region, and by making that step to accept a volunteer position, I suddenly started to meet people all across the country. And all of these very dear friends and colleagues from across this nation are invaluable. AHRA members will help you recognize your talents and the areas where you need support. By going into the educational offerings of AHRA, you are able to, in a short time, get a bunch of information that you weren’t able to get on your own.
IE: What are the greatest challenges facing an administrator today?
Edge: I think they are probably twofold. The first is people. Making sure you have good-quality employees, who do good-quality work, and are committed to providing excellent patient care. You also need to make sure they are recognized for it and help them develop their careers. And I think the other piece is trying to stay on top of all the information, all of the changes that occur on an almost daily basis—processes, technology—that impact how we deliver good quality patient care.
IE: How vital is a strong radiology administrator to the health of the department?
Edge: I think it’s critical. Your biggest role as an administrator is as an advocate for your people, from the radiologists to the front desk. The entire process of getting the patient in for an imaging service comes under your direction—hence, the title. You have to understand the process so you can advocate for the people, the dollars, and the equipment required to best take care of your patients.
IE: What do you see as the biggest growing need for administrators, in terms of challenges or skill sets?
Edge: It’s always been the case, but I think people skills are key. If you can’t defuse conflict, if you can’t have a reasonable conversation, if you can’t explain to the people you report to what you need, and if you can’t communicate to your staff the organizational goals and strategic plan of the organization, then you won’t be effective.
IE: What are the most important qualities an administrator should possess?
Edge: Integrity is number one. People have to know you say what you mean and mean what you say. You also need excellent organizational skills, people skills, and communication skills, both verbally and in writing. It’s important to have good negotiation skills, too, not just for getting the best deals for your affiliate or organization, but to be able to negotiate with other departments, management, and your staff to create a win-win situation. I also think you need to have a calm demeanor, so people feel that they can come to you with problems.
IE: What current project are you most excited about?
Edge: We’re expanding our services to provide service in Stockton, where we have not been able to provide care before. The building is slated to open on December 4 and will be a full-service facility, offering CT, MR, bone density, full-field digital mammography, DR, and digital fluoro—everything except nuclear medicine. We also will be building a replacement facility at our main clinic. It will grow from 6,700 to 15,000 square feet. Renovations will be completed in early 2008.
IE: What advice would you offer to an administrator starting out today?
Edge: Make sure you join AHRA and build your network. There is no AHRA member who doesn’t answer your phone calls or answer your e-mail. They are there to help you, and it saves you from reinventing the wheel and can help you get started on whatever it is you’re working on, because somebody has done it already. Being able to get that information from really experienced people is just a godsend. You can’t put a dollar figure on how valuable that is.
Dana Hinesly is a contributing writer for Axis Imaging News. For more information, contact .
