Nuclear technologists need to lead facility accreditation efforts
The means of accreditation is through adherence to established guidelines for acquisition and processing. Therefore, acquisition protocols will need be more clearly defined, said Dunn at the 2008 American Society of Nuclear Cardiology (ASNC) conference.
Acquisition varies depending upon whether it is rest/stress, stress/rest, two-day protocol or stress only protocols. While two-day protocols are not the most convenient in office settings, they provide the best images, said Dunn, technical director of nuclear cardiology at Maine Cardiology Associates in South Portland, Maine.
He cautioned that gating patients with irregular heart rates, especially patients with atrial fibrillation or frequent ectopy, can lead to an inaccurate determination of ejection fraction and wall motion due to counts being placed in wrong bins and significant variation of R-R interval, as well as greatly increased imaging time that can lead to increased patient motion.
He also stressed the need to be “careful with some systems in gating patients with pacemakers, as they will detect the pacer spike, which will lead to an overestimated heart rate and counts being placed in wrong bins.” His advice: disable the pacer before imaging, if possible.
To avoid rescans, it is essential that nuclear medicine technologists review each set of images before releasing a patient to ensure there is not excessive motion, artifact, bowel interference or corruption of data. “If you have poor image quality for any reason, it is much easier to immediately rescan the patient than to reschedule another appointment,” Dunn noted.
For processing considerations, he said that it is essential that the technologist and reading physician collaborate to create specific defaults for processing, which usually requires customizing default settings to physician preferences. “You must create settings for all of your imaging protocols, such as one-day, two-day or dual isotopes. Once these settings have been created, it is essential that the technologist does not change them—such as changing filters or frequency cutoffs—unless under the direct supervision of the reading physician,” Dunn stressed.
He also advised technologists to review all raw data—motion, artifacts, quality of images—before processing, adding that it is particularly important to have both rest and stress images aligned the same, so they can be evenly and equally compared.
“With the ever-increasing scrutiny on image quality and the inevitable need for all U.S. facilities to be nationally accredited, it is incumbent upon nuclear medicine technologists to provide the highest quality studies to its providers for purposes of certification and reimbursement,” Dunn said.