A new study says that in elderly patients who are undergoing multi-detector CT examination of the pancreas and biliary region, doctors may safely reduce the dose of a contrast agent by 10 percent. Doing this will reduce the costs as well as the risks associated with the tests, according to the study. The Department of Technical Radiology at Nagoya University School of Health Science in Nagoya, Japan undertook this study.
"When interpreting CT images acquired using the established protocol in our clinical practice, it was noted that in some examinations of elderly patients, contrast enhancement of the pancreatic parenchyma was too intense," said Shigeki Itoh, MD, lead author of the study. "Therefore, we speculated that it might be possible to reduce the dose and rate of contrast material injection without adversely affecting the degree of contrast enhancement in elderly patients," said Dr. Itoh.
The study included 112 patients, ranging from 23-80 years old who had known or suspected pancreatobiliary disease who were split into three groups (60 years old or younger with a contrast injection of 0.08 milliliters/kg/sec, 60 years old or older with a contrast injection of 0.08 milliliters/kg/sec, and 60 years old or older with a contrast injection of 0.07 milliliters/kg/sec).
Group 3 had a 12.2% reduction in the volume and rate of contrast material injection. According to previous studies, contrast enhancement in the vessels and the organs of the abdomen increases with an increase in the volume and rate of contrast material injection. However, Dr. Itoh said that this wasn't the case in his study. Dr. Itoh noted it is essential to administer contrast material only at the volume and rate needed to achieve an adequate level of contrast enhancement for diagnosis.