Ultrasound-CT protocol for appendicitis eval could bring big savings

An ultrasound-CT protocol for appendicitis evaluation provides potentially larger savings over the standard CT-only protocol, according to a study published in the January 2014 issue of the American Journal of Roentgenology.

As concerns are raised about the rising cost of health care in the U.S., comparative effectiveness research becomes a critical way to assess the value of procedures and cut down on expenses. While appendicitis can be diagnosed by either CT or ultrasound, CT is more expensive and emits ionizing radiation. Ultrasound is slightly less accurate, but is less costly, widely available, and offers the benfit of no ionizing radiation.

Laurence Parker, MD, of the Thomas Jefferson University in Philadelphia and colleagues wrote, “This study considers whether using a slightly less accurate but less expensive imaging technique with no ionizing radiation exposure might offer more benefits than the current almost universal use of CT in appendicitis evaluation in the United States.”

The researchers utilized data from Centers for Medicare & Medicaid Services (CMS) datasets, national hospital discharge surveys, radiology information system cases, and U.S. Census Bureau life tables. Estimations were then made for the costs of imaging tests, excess surgeries, and excess surgical deaths for the ultrasound-CT protocol and the CT-only protocol.

Findings demonstrated a positive predictive value of 92.5 percent for CT and 91 percent for ultrasound. Upon analysis of CMS files, it was revealed that CT utilization was approximately two exams per patient and for ultrasound was almost zero. The cost of the CT-only imaging protocol was estimated to be $547 per patient, whereas the cost of a limited ultrasound study would be $88 per patient.

Cost savings in imaging (notwithstanding the cost of extra surgeries and extra surgical deaths) is estimated at $24.9 million for the U.S. population per year. According to model VII by the Committee on the Biological Effects of Ionizing Radiation, avoiding a 12.4 mSv exposure for 262,500 people would prevent 180 excess cancer deaths.

“We hope that the current study encourages further examination of the potential cost and radiation savings of ultrasound in appendicitis evaluation. It is hard to change a diagnostic practice that is regarded as successful. This study suggests large rewards for doing so,” wrote Parker and colleagues.