Radiation Protection in Gastroenterology
The use of ionizing radiation in gastroenterology is somewhat in transition. In the past, gastroenterologists performed a variety of interventions involving radiation exposure, including performing gastrointestinal X-ray studies, placement of small bowel biopsy tubes, oesophageal dilation, and assistance with colonoscopy, as well as diagnostic and therapeutic procedures on the pancreatico-biliary system during ERCP (endoscopic retrograde cholangiopancreatography). Most of the current X ray exposure is from ERCP, luminal stents and dilation while the other procedures are becoming supplanted by improvements in diagnostic equipment and techniques. Gastroenterologists who are involved in ERCP procedures may work at specialized centres and may perform multiple procedures daily. In many circumstances where fluoroscopic and/or X ray equipment are used, gastroenterologists have the opportunity to minimize risk to patients, staff and themselves.
When fluoroscopy is used to assist with colonoscopy, dilation or luminal stent placement, the least amount of fluoroscopy time possible is recommended.
During ERCP, fluoroscopy is used to verify position of the endoscope and its relationship within the duodenum. The placement of catheters and guide wires is also verified fluoroscopically. Once contrast injections are performed, fluoroscopy is used to evaluate the anatomy of the ductal systems of both the biliary tree and pancreas, and to help define potential diseases present. Photographic documentation is usually obtained to record the findings, either by capturing the last fluoroscopic image or spot radiographs. Finally, the use of fluoroscopy to assist therapy, such as sphincterotomy, stone extraction, biopsy or cytology, and stent placement is required. Additional devices that allow direct visualization of ductal anatomy may ultimately reduce the need for fluoroscopy.