ARRS: Lower tube voltage slashes dose without impacting quality

Radiation dose in lumbar spine CT can be cut 41 percent by accounting for patient size, according to a study abstract in the electronic exhibit program at the American Roentgen Ray Society Annual (ARRS) annual meeting in Washington, D.C.

Researchers at Yeouido St. Mary’s Hospital in Seoul, Korea, sought to assess the effect of lowering tube voltage to reduce radiation dose on image noise.

At total of 107 patients were included in the study, and were imaged using semi-automated attenuation-based tube potential selection, which optimized tube potential at 100 kilovoltage, as opposed to 120 kilovoltage, according to Junghyun Lim, MD, lead author of the study, and colleagues.

Images were reconstructed using either filtered back projection or iterative reconstruction, and based on the subjective review of two musculoskeletal radiologists, either method resulted in images of diagnostic quality at the lower tube voltage. Objective measures of image noise favored iterative reconstruction, according to Lim.

The reduction in tube voltage decreased radiation dose from a mean of 21.78 mGy to a 12.77 mGy.

In a press release, Lim noted that his facility, which performs up to 150 lumbar CTs a month, now conducts them at 100 kilovoltage using filtered back projection based on the results of this study.