By Juliana Bunim
As concerns mount about unregulated radiation dosages from CT scans, Rebecca Smith-Bindman’s study will examine if ultrasound is a viable alternative for patients with renal stones.
Smith-Bindman, MD, a professor of radiology at UCSF, recently received a $9.2 million comparative effectiveness award through the federal economic stimulus package known as the American Recovery and Reinvestment Act (ARRA).
The ARRA grant is to study whether emergency room patients with renal stones can be treated as effectively with ultrasound as radiation-delivering CT scans. The grant follows Smith-Bindman’s research published last December that found radiation doses from common CT procedures vary widely and are higher than generally thought, raising concerns about increased risk for cancer.
That research reviewed procedures performed on 1,119 patients at four San Francisco Bay Area institutions over five months and found a 13-fold variation between the highest and lowest radiation dose for each type of CT procedure.
“Dose awareness has increased profoundly in the last six months, and at UCSF, we’re really making a concerted effort to try and reduce the doses associated with a large number of CT scan types,” said Smith-Bindman. “That’s resulted in improved safety by lowering the dose for the same study type. “
The grant is among more than 45 awards UCSF has received through ARRA that have been targeted towards understanding of what works – and doesn’t – in real-life hospital and clinic practice settings. Known as comparative effectiveness research, the projects involve multiple medical centers throughout the nation, assessing actual clinical practice and patient outcomes in areas ranging from prenatal testing and children’s oral health to treating stroke and traumatic brain injuries.
The grants are particularly significant in the ongoing debate over health care reform, with the increasing scrutiny on both the cost of health care and the quality provided. In that context, comparative effectiveness research – or identifying the best practices among different health care models in preventing, diagnosing, treating, and monitoring disease — has been touted as one possible solution to rising health care costs.
Decreasing Exposure to Radiation
The ARRA grant will address a concrete way to decrease the amount of unknown radiation patients receive from medical imaging. The goal of the grant is to assess a broad range of outcomes (including accuracy, safety, cost and effectiveness) that may be associated with the choice of initial imaging test The broad goal is determine if it is possible to reduce the number of CT scans performed in patients with suspected renal stones, by replacing them with ultrasound scans that are not only less expensive, but safer as they does not expose patients to radiation, said Smith-Bindman.
Renal stones were chosen for the study because they are a common reason patients go to the emergency room, and a CT scan is now the typical test used for diagnosis.
“In the past, as recently as 15 years ago, the number of patients who went to the ER with acute flank pain who would be imaged with CT would be in the ball park of 10 percent percent. Now 85 percent of these patients get imaged with CT,” she said.
“Renal stones are a good target disease to start with because it’s an area where we can really change practice. Patients with renal stones get repeatedly scanned, yet they’re typically young, healthy patients. It’s a group where radiation could be particularly harmful and where we have another alternative test that may be just as good, if not better.”
The three-year trial will take place in 10 hospitals across the country and involve approximately 3,500 patients who go to the ER with renal stones. They will be treated in one of three arms of the study:
- Randomized to the radiology department for a CT scan
- Randomized to the radiology department for an ultrasound and
- Randomized for an ultrasound in the ER itself, where all ER physicians in the trial are trained to do an ultrasound.
According to Smith-Bindman, no patient in the study is at a disadvantage, regardless of which arm he or she is randomized into. “To randomize patients into three arms I had to feel all arms were equally good. In this case I feel there’s equipoise. It’s an area where all the options are good and our study will find out which one is best. “
The patients will be followed for a year after their initial visit to determine the differences in outcomes based on randomization including quality-of-life issues, pain differences, need for a different kind of procedure and later hospitalizations.
“We’ll look at which arm is least and most cost efficient, how long the patient stays in the ER, misdiagnosis and accuracy,” said Smith-Bindman. “My goal is to try to improve the choice of diagnostic test for this clinical situation.”