March 20, 2014 | The yellow bird on the little badge that Tobias Struffert, MD, wears attached to his lead apron looks as if Twitter® had expanded into the hardware business. However, this bird indicates a gadget with quite a different hashtag: real-time radiation dose management.
Text: Doris Pischitz
Photos: Jürgen Hinterleithner
When Dr. Tobias Struffert, senior physician in the Neuroradiology Department at University Hospital Erlangen, Germany, prepares for an intervention, he dons his scrubs along with the film dosimeter and his lead apron, and then clips on an additional item: a 4 x 4 centimeter badge with a yellow bird printed on it. The badge is part of RaySafe i2TM, an active dosimetry system that gives real-time insight into personal radiation exposure, as well as access to time-stamped dose data.
Value of Real-time Dose Information
Radiation dose data collected by the RaySafe i2 dosimeter during each intervention is transferred directly to a touchscreen display right next to the angiography system’s displays. Struffert has been using it for 18 months now, along with the conventional film dosimeter required by German law. This film dosimeter has to be sent to the Munich-based Helmholtz ISS Institute of Radiation Protection every four weeks for analysis. “When you get the data back, there’s no way of finding out when and why a dose might have been recorded,” says Struffert. He recalls an incident some years ago when the analysis showed a peak of seven millisievert, highlighted by the hospital’s radiation safety officer. “I had no chance to find out when, why or during which procedures I was exposed to such a high radiation dose,” Struffert says.
Immediate Measures Against Scatter Radiation
RaySafe i2, by contrast, not only records time codes along with data but also enables Struffert and his team to react to any peaks immediately during the ongoing intervention. “RaySafe gives us immediate feedback about the current scatter radiation. This enables us to react directly,” says Struffert. For example, he quickly realized how important it is to place the lead glass barrier correctly and adjust it each time when repositioning the patient table or the C-arm.
Typical vs. Individual Radiation Dose Patterns
With the badge connected to a computer via a docking station, Struffert can also read out, save, and analyze the time-stamped data from past exams. By looking up the respective exams in the hospital’s picture archiving and communication system (PACS), he found typical dose curves for standard diagnostic exams and also realized that each interventional case is individual not only from a clinical perspective – and thus has its own distinct dose curve. To allow him to look more closely into these patterns, Struffert would need an automated connection between the angiography system, the PACS, and the RaySafe system.
“The Future Dosimetry is Digital.”
Struffert also sees RaySafe’s potential in interventional cardiology. “With an intervention in the thorax, the interventionalist is much closer to the X-ray source than I am as a neuroradiologist.” He is certain that lawmakers will sooner or later require real-time dosimetry: “The future is digital.”
And now, how did the little yellow tweeting bird get onto the badge? It’s a canary. Coal miners used to bring them underground to warn them of life-threatening concentrations of carbon monoxide, but unlike RaySafe i2, when the birds went quiet it meant imminent danger.
Doris Pischitz is Chief Editor at Siemens Healthcare.