Experts discuss the basics of radiation quality control and quality assurance programs.
Bill Zimmermann, engineering manager/physicist, Fluke Biomedical, with a colleague.
If you ignore [radiation] quality assurance and quality control, you will just get burnt big,” said Frederic Mis, PhD, CHP, recently retired owner of Multi Industrial Services in Webster, NY—without intending any pun. Mis specializes in radiation quality control and quality assurance, assisting institutions with their radiation safety programs. Clients include nuclear power plants, veterinarian clinics, and health care organizations.
Inadequate quality control can have many negative consequences for any organization. In health care, poor QC can result in physical harm to patients, staff, and even visitors. “[Consider] the dental office, podiatrist, or a patient sitting in the hallway waiting—they are all at risk for exposure. Facilities with bad designs can have a lot of exposure. In some cases, I’ve noticed more than the average power plant worker gets (due to the nature of their job),” Mis said.
Mis has worked with health care facilities where “radiation protection is almost perceived as an accessory,” while other institutions have quality control and quality assurance programs in place to ensure low-dose efforts. Both extremes, and those in between, all share the same challenge of maintaining adequate programs, incorporating the latest evidence, and keeping complete documentation. A good program will encompass all aspects of radiology.
Quality control and quality assurance aren’t just about dose; image quality is also ensured. “What are we getting for our exposure? Are we getting good resolution? Are we getting good information? Are we able to help the attending physician make the best diagnosis possible?” Mis asks.
If the answer is no, the end result could be misdiagnosis of a disease or the wrong determination of trauma (eg, missed fractures). “In the case of nuclear medicine, there could be a poor understanding of blood flow or a missed opportunity to catch a tumor at its earliest stages,” Mis said. QA/QC radiology programs are key to avoiding these repercussions.
Why QA/QC?
Fluke Biomedical offers the tools and testing equipment to support a quality assurance/quality control program.
Successful quality programs will protect not only the patient, but also the medical staff and the bottom line. Mis has been approached in the past by concerned staff who suspect their equipment is leaking radiation. “When that happens, it’s usually the last stage of something going wrong,” said Mis, who is “fairly confident” that in those cases he will ultimately find something that agrees with the employees’ gut feelings.
Of course, by then, the problem has often become more complex and more expensive to resolve, if a solution even remains possible. In many cases, late-stage problems require replacement rather than repair.
If Mis deems a piece of radiation equipment unsafe or defective, he will terminate the ability of the users to operate it. “That’s an expensive problem for them. If they’re beginning to sense that something is not quite right, they should call in outside help earlier. They’ll be amazed at how much they are able to save,” said Mis.
QA/QC can also help to protect revenues by ensuring continued operation, reducing liability and enhancing reputation through proven safety. In some instances, such as mammography through the Mammography Quality Standards Act and Program (MQSA), there is no choice; radiation regulations have already been established. In other cases, regulation is around the corner. In 2012, imaging centers that offer advanced imaging services (CT, MR, nuclear medicine, and PET) will need to be accredited by one of three CMS-designated bodies to continue to receive relevant reimbursements.
Accreditation programs already cover quality control and quality assurance measures, and facilities that do not meet the specific requirements of the accrediting organization are in danger of revocation. This can impact reimbursement as well as reputation. “If you’re a mammography facility and you lose that, you’re pretty much out of business,” said Bill Zimmermann, engineering manager for Fluke Biomedical, headquartered in Everett, Wash.
A Team and Tools
Fortunately, each facility can implement the methods and tools that work best for its specifics, as long as the program meets the regulatory standards. For instance, some facilities will use in-house staff, while others may rely on consultants, like Mis.
In-house staff who manage radiation QC/QA programs may include medical physicists, biomeds/clinical engineers, and/or technicians. These teams are often found in larger facilities; smaller facilities generally lack the resources to support an in-house program. Instead, they hire contractors to come in on a regular basis to perform quality checks per state regulations, which can vary depending on the institution, according to Mis.
Tools, both physical and digital, can help with the actual details of a quality program, from testing and measurements to documentation and analysis. Persons in charge of QA/QC take measurements related to dose, performance, and quality through the entire spectrum of radiation medical imaging devices—”from the film cassettes or the digital image receptors all the way up to the monitors or the film processors,” Zimmermann said.
The Process and Products
Because of the variety of modalities and measurements, a range of tools is often used to acquire data. Fluke Biomedical seeks to continuously expand this range so as to keep up with technology. The company offers equipment used to make the measurements that support a quality program, including phantoms, test patterns, dosimeters, and mammography-specific tools.
In addition to developing new technologies, Fluke also seeks to improve its standards. “We always strive for better accuracy. And over time, accuracy has improved, but probably the biggest strides have been in convenience, usability, and features like that,” Zimmermann said.
Improvements are both large and small. Newer smart features include the ability to turn a system on and find the previous settings still intact as well as a fluoroscopy test that automatically determines the type of fluoro beam on its own (continuous versus pulse).
Fluke’s newest family of products, the TNT 12000 X-Ray Test Tools System, includes a wireless detector, dosimeter, mA/mAs measurement, wireless display, and test automation software. “It provides a complete tool kit for all of the diagnostic x-ray QA measurements that a physicist, biomed, clinical engineer, or service engineer would need to make,” Zimmermann said.
With one exposure, the TNT 12000 measures kVp, radiation dose, dose rate, time, and half-value layer (HVL). The TNT 12000 DoseMate dosimeter and ion chambers enable greater accuracy than previous models in the dose and dose-rate measurement of radiographic, dental, fluoroscopic, and CT imaging systems.
Zimmermann believes the product’s greatest advantage is the wireless capability. “There are no cables to connect or disconnect. Ease of use is much better than with our older products. And eliminating those long, expensive cables saves money in the long run,” Zimmermann said.
The TNT 12000 has become a fast favorite of Mis’s. “I like the 12000 a lot, in particular because it puts out information in a fashion that’s organized so I can, at a glance, begin to correlate output versus results and see consistency. I don’t even have to see the film. With the Fluke 12000, I can predict what that film will look like and whether the device is going to meet standards just after a couple of shots because everything is laid out nicely for me,” Mis said.
The results are so evident that Mis likes to perform the test with the equipment owner or manager present. “If an untrained eye can recognize right away that the device is performing well or has an issue, it’s much easier when I tell them they need to replace their equipment. It’s not me, but what the machine is saying,” Mis said.
One of Mis’s most telling measurements is repeatability. If a device shows consistent error when measured (say, the device indicates 80 kVp, but test measurement is 70 kVp, every time), the instrument has a bias. If the institution takes measures to counteract the bias, it is not a serious problem. If, however, error is inconsistent (the device indicates 80 kVp, but is measured at 50 kVp in one test and 80 kVp in another), “the equipment then becomes a contributing cause to a missed diagnosis,” Mis said. And no one wants to experience that burn.
Renee Diiulio is a contributing writer for Axis Imaging News.
