Sunday, December 1 | 2:50 p.m.-3:00 p.m. | S5-STCE1-3 | Learning Center Theater 1
Carbon nanotube (CNT) sources for digital x-ray systems have clinical and environmental advantages over standard filament tubes in fluoroscopic imaging, according to a study presented in the session.
Amar Prasad Gupta, PhD, a research fellow at Harvard Medical School, will present a comparison between a CNT and a filament tube bought from different vendors. Both tubes were rated for use at a maximum of 70 kilovolts (kV), a maximum current of 3 milliamps (mA), and a focal spot 0.4 millimeters. The researchers measured and compared their physical dimensions and measured fluoroscopic patient dosage by operating the x-ray system in pulsed mode at 50 kV and 1 mA using a MOSFET circuit to switch digitally with 40-millisecond pulses at a 50% duty cycle. Next, they imaged a cadaver hand using a Varex flat panel at different kVps, but constant mAs with both tubes and compared image quality. Lastly, they interviewed the vendors about the manufacturing process of the tubes and compared the environmental impact during the production.
The digital CNT x-ray source was about 75% smaller, weighed about 50% less, and consumed 17% less energy producing x-rays of the same energy and current, according to the findings. Moreover, in the fluoroscopic setting, where the x-rays are continuous, the CNT x-ray tube produced approximately 44% less radiation dose due to perfect digital switching. The cadaver hand imaging at different magnification and kVps shows similar quality for both x-ray tubes, they noted. When comparing manufacturing process, the researchers found that CNT x-ray tubes have less carbon emissions because they are produced in simple vacuum ovens in huge quantities, whereas filament x-ray tubes are manufactured one by one using flammable gases.
Digital CNT x-ray sources are “the future of radiological imaging and sustainable in production,” Gupta and colleagues suggest, and they outperform conventional filament tubes in every aspect. That is better for patients, medical practitioners, and the environment, the team says.
Tune in to this session on value-based, equitable, and sustainable radiology to learn more.
