AJR: Reconstruction technique reduces radiation dose during CT
A new CT technique could allow for the reduction of up to 65 percent of the radiation dose patients receive during a routine whole-body scan. This radiation reducing tool, adaptive statistical iterative reconstruction, is described in a study published in the Sept. issue of the American Journal of Roentgenology.

Iterative reconstruction allows radiologists to reduce the noise in an image and improve image quality, while significantly reducing the radiation dose, according to the authors.

Amy K. Hara, MD, from the department of diagnostic radiology at the Mayo Clinic in Scottsdale, Ariz., and colleagues performed CT scans using the newly adapted low-dose ASIR method and the standard dose method without ASIR both on a phantom and 12 patients.

"We found nearly identical image quality using the reduced dose CT method with ASIR compared with the standard dose CT method without ASIR," said Hara.

In the study, patient radiation doses were reduced up to 65 percent using the low-dose iterative reconstruction method, according to the authors. They reported that average radiation dose delivered during the low-dose CT with iterative reconstruction was 470 mGy; the average dose delivered using the standard dose CT without IR was 894 mGy.

Based on their findings, the authors concluded that their study is significant because it shows that the low-dose ASIR method can significantly decrease the radiation dose along with the many risks associated with radiation exposure. “In future studies, it will be important to not only evaluate image quality but to assess diagnostic accuracy,” they wrote.

"Finding a way to reduce radiation dose for routine body CT imaging has been an ongoing concern for many… ASIR is new to CT but in our practice it has been very successful," Hara said.