RSNA 2017: Imaging Informatics Preview

Type of dose monitoring software affects SSDE results

By Erik L. Ridley, staff writer

October 30, 2017 --

Tuesday, November 28 | 3:40 p.m.-3:50 p.m. | SSJ22-05 | Room S403B
An Italian team found that four commercial radiation dose monitoring software applications calculated size-specific dose estimates (SSDEs) differently, potentially affecting data comparisons between institutions.

Radiation dose monitoring systems play an important role in the registration and analysis of the dosimetric index from x-ray procedures, supporting users in managing the data and calculating patient-specific dose metrics such as SSDE, said Sergio Zucca, a medical physicist at the Azienda Ospedaliera Brotzu in Cagliari, Italy.

Seeking to verify the accuracy of SSDE calculations, the group acquired CT images using an anthropomorphic phantom on the same scanner and then applied Matlab (MathWorks) software to calculate SSDE from water-equivalent diameter or effective diameter, using the image at the center of the scanning region or the average of all of the axial images. Next, the researchers compared those calculations with those recorded by Radimetrics (Bayer HealthCare), DoseWatch (GE Healthcare), NexoDose (Bracco Imaging), and RDM (MPTronic).

The team confirmed that SSDE evaluation could be affected by the different calculation methods implemented in each software application.

"In particular, relevant differences were found in scanning regions with a high variation of patient attenuation (e.g., neck and shoulder) or when the patient was off-centered within the [field-of-view]," Zucca told

The study results highlight the equipment selection and commissioning process for radiation dose monitoring software; medical physics experts, radiologists, technologists, and IT should take part in a team effort, he said.

"Before clinical usage, [the software's] data registration, analysis, and calculation should be carefully reviewed under the responsibility of a [medical physics expert]," Zucca said. "This seems to be particularly true in a multi-institutional framework, as each user should be aware of the quality and limitation of his data, in order to compare findings."

Get all of the details by attending this Tuesday afternoon presentation.