| It occurred to me it might be possible to augment the protection so you could work behind the screen and yet still be as functional right near the table. Martin Magram, M.D. Invention Aims to Eliminate Physician Radiation Exposure During Angiography Plato’s adage about necessity being the mother of invention has proven true again. A Maryland radiologist’s dissatisfaction with traditional radiation safety precautions during coronary angiography led him to create a new device that he said nearly eliminates radiation exposure to the physician. Martin Magram, M.D., an assistant professor in the Department of Diagnostic Radiology at the University of Maryland Medical Center in Baltimore, said the longer curved handle he developed to attach to the patient table gives him flexibility in performing coronary angiograms while significantly cutting his own radiation exposure. The handle, he said, allows the physician to remain safely behind the lead plastic shield while retaining table control for panning.
“It has always bothered me that the head, arms and legs are exposed. We wear a lead apron and some of us wear lead glasses and a thyroid shield, but that’s not enough,” said Dr. Magram. “It occurred to me it might be possible to augment the protection so you could work behind the screen and yet still be as functional right near the table.” A study Dr. Magram conducted to test his invention attracted attention via the annual meeting of the American Roentgen Ray Society (ARRS) in Vancouver, British Columbia, earlier this year. Using his technique and recording radiation exposure to various parts of the physician's body during coronary angiography on 25 patients, Dr. Magram compared the results to physician's radiation exposure during 25 procedures using conventional radiation protection. The new table control device, he concluded, reduced radiation exposure to the physician's head, arms, and legs by 90 percent. Dr. Magram’s curved extension bar replaces the traditional short handle. “The extension bar is rather like a broomstick, which is a yard long and curves behind the leaded glass panel,” he said. He added that his goal was to put the physician as far out of danger as possible, while still being able to do his or her job effectively. “You don’t have to be standing right next to the table if you need to pan while you’re doing the angiogram that is moving the table with the patient on it,” Dr. Magram said. “By standing behind the shield and moving the table with the bar connected to the table, your entire body is protected from radiation, so you get only about one tenth of the radiation that you would have gotten without the shield and bar.”
Ergonomics Still an Issue Whether the technique can be modified to suit the needs of other radiologists remains to be seen. It has been tested only during coronary angiography. Donald L. Miller, M.D., professor of radiology at the Uniformed Services University in Bethesda, Md., acknowledged the widespread physician interest in radiation protection. Since the principle of “as low as reasonably achievable” (ALARA) still guides institutions—which check exposure regularly via badges and review the practices of staff members who receive 10 percent and 25 percent of the permitted annual dose—safety research collaborations between angiographers and interventional radiologists also continue to investigate ways to improve protection. Dr. Miller said that while Dr. Magram’s device does reduce radiation dose to the body, it doesn’t address an issue just as troublesome to physicians—the ergonomic problems associated with the lead aprons routinely worn to shield the body. Weighing between 9½ and 13½ lbs., the aprons stress the neck and spine and may cause significant injuries. Because Dr. Magram’s reported reduction in radiation exposure occurred while he was wearing a lead apron, said Dr. Miller, his technique does little to address those stress issues. “Most of us who do this work think there is a clear relationship between spine problems suffered by some physicians and the kinds of positions we are in and the weight of the lead protection,” said Dr. Miller. Working Toward Eliminating Lead Gowns Dr. Miller added that interventional radiologists’ need to stand in various places around their patients might prevent them from utilizing the technology. “The area of interest of the patient’s anatomy can be anywhere from the head to the foot and the operator could be standing anywhere. In coronary angiography, the operator is standing at the patient’s hip and that’s a relative constant for most cardiology procedures,” said Dr. Miller. However, Dr. Magram said that because he was able to clearly demonstrate a significant exposure reduction, this encourages further exploration of his technique and others like it. “Previously people did things a certain way and that’s how we were taught. Now we are rethinking all this,” he said. The new technique may eventually free physicians from the need to wear lead gowns, Dr. Magram explained. “As the sophistication of radiologic diagnostics has increased, it is tragic when a physician can no longer perform procedures because the lead gowns cause onset of neck or back degeneration and the physician becomes unable to tolerate the weight of a lead gown,” he said. “This may extend by years their ability to apply the skills they have developed over long careers of serving patients.”
Dr. Miller said that even as new techniques are developed and evolve, the basic principles of radiation safety will always apply. “Keeping the image receptor as close to the patient as possible, collimating tightly around the area of interest, using reduced-dose pulsed fluoroscopy and limiting fluoroscopy time and the number of angiographic images, will reduce dose to both the patient and operator,” he said. RSNA Extra: To read the abstract for “Reduced Physician Radiation Exposure during Coronary Angiography with New Radiation Protection Technique,” presented at the 2006 annual meeting of American Roentgen Ray Society, go the RSNA News Extras page at RSNA.org/Publications/rsnanews/extras.cfm. Radiation Dose Optimization and Safety at RSNA 2006 Special considerations for angiography will be among the topics examined during the RSNA 2006 Categorical Course in Diagnostic Radiology Physics. In addition to angiography, the course will also touch on fluoroscopy, CT and mammography. Attendees may register for individual sessions of the course. To register for these sessions or any other courses, go to rsna2006.rsna.org and click on Registration, Housing & Courses. Categorical Course in Diagnostic Radiology Physics: From Invisible to the Visible—The Science and Practice of X-Ray Imaging and Radiation Dose Optimization RC125: Introduction, Radiographic Image Formation and Characteristics, Measures of Image Quality RC225: Medical Radiation Dosimetry, Radiation Risks in Diagnostic Radiology, Balancing Risks and Benefits in Medical Radiography RC325: A. Computed Radiography/Digital Radiography: Adult, Pediatric and Radiologist, Perspective of Controlling Dose and Study Quality RC425: Fluoroscopy (Gastrointestinal): Dose, Clinical Practice—Controlling
Dose and Study Quality RC525: CT: Dose and Image Quality RC625: Clinical Practice: Controlling Adult and Pediatric Radiation Dose and Study Quality RC725: Special Procedures (Angiography): Dose, Image Quality and Clinical Practice RC825: Mammography: Dosimetry, Screen-Film and Digital | 
