TOMOKAZU SHOHJI, Presenter: Nothing to Disclose

Norio Nakata MD, Abstract Co-Author: Nothing to Disclose

Sosuke Higuchi RT, Abstract Co-Author: Nothing to Disclose

Atsushi Tachibana MSc, RT, Abstract Co-Author: Nothing to Disclose

Yoh Katoh RT, Abstract Co-Author: Nothing to Disclose

This software was developed to calculate organ dose from computed tomography (CT) value per pixel using monochromatic imaging created by dual-energy scans.

The CT system used was SOMATOM Flash (Siemens AG). A combination of 80 and 140 kV was used as the scan condition to create 80-keV head monochromatic images. Next, the CT value/linear attenuation coefficient transformation formula at 80 keV was derived using Catphan module, in which substances with a linear attenuation coefficient for each kind of energy as immediate values were embedded. The transformation formula was subsequently transformed to generate linear attenuation coefficient images by superimposing it on CT value images. Finally, each pixel dose was calculated by filtered back projection and using the strength distribution of the X–Y surface, reflecting the X-ray strength of a bowtie filter as well as linear attenuation coefficient images. Then, the value registered on the glass dosimeter (GD-352M) inserted into a head phantom was compared with the calculated value.

Calculate dose of lens, salivary glands, oral cavity, cerebellum, and cerebral, was higher than the measurement dose of the glass dosimeter. The margins of error between the measurement dose and the calculate dose were maximum 10 %.

Calculate doses are in good agreement with the measurement dose. By using this software, it is possible to obtain organ absorbed dose from monochromatic CT imaging with one click. And this software is useful for the evaluation of organ high cancer risk and children.

This software is useful for the evaluation of organ high cancer risk and children.

SHOHJI, T, Nakata, N, Higuchi, S, Tachibana, A, Katoh, Y, Ultra-fast One Click Organ Dose Calculation Software Using Monochromatic Imaging in Dual-energy CT Scans.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14013694.html