Mayo Clinic researchers in Rochester, Minn, have shown promising results of new protocols to reduce radiation dosages used to acquire perfusion and other CT images.

At the 52nd Annual Meeting of the American Association of Physicists in Medicine, a presentation titled “20-Fold Dose Reduction Using a Gradient Adaptive Bilateral Filter: Demonstration Using in Vivo Animal Perfusion CT” was given by Mayo Clinic medical physicist and radiologists, Cynthia McCollough, PhD.

McCollough showed results of a new image-processing algorithm that could significantly lower radiation dose during CT perfusion. According to the presentation, the Mayo team’s new algorithm produces a high-quality perfusion CT with up to 20 times less the radiation used under existing protocols.

The new technique involves detecting changes in blood volume and flow that reveal injuries to vessels or a tumor’s response to treatment. Information from each consecutive scan is digitally cross-referenced with other images taken during the exam to improve image quality and reduce distortions.

While this technique has thus far been used in animal models only, the researchers are now looking to apply the methodologies into clinical practice.

Another team of Mayo radiologists and physicists recently implemented a new routine head CT protocol that reportedly cuts radiation dose by nearly 50 percent.

Head CT doses are typically 75 mGy. With Mayo’s new head CT protocol, patients are exposed to a dose of only 38 mGy.

Mayo neuroradiologist David DeLone, MD, said in the press announcement that Mayo clinicians using the new head CT protocols are obtaining high-quality images, more consistently and in shorter times.

For information, visit

(Source: Press Release)