Abstract
Background
320-row volume computed tomography (CT) allows CT dose to be reduced while maintaining image quality.
Purpose
To evaluate image quality of low-dose non-contrast temporal bone CT using single volumetric 320-row multidetector CT technique.
Material and Methods
A total of 125 patients were included in our study. Two low-dose protocols, including 135 kV tube voltage with 5 mAs tube current and 80 kV tube voltage with 5 mAs tube current, were chosen based on results of present phantom study. For evaluating subjective image quality, conspicuity of anatomic landmarks were assigned a score using a five-point scale. Objective image quality analysis was performed by analyzing regions of interest on axial soft-tissue and bone reconstructions. Effective dose was calculated from dose-length product.
Results
Mean effective radiation dose for 120 kV and 75 mAs protocol (control group) was 0.29 ± 0.04 mSv; for 135 kV and 5 mAs protocol (study group A), this value was 0.02 ± 0. 003 mSv; and for 80 kV and 5 mAs protocol (study group B), this value was 0.005 ± 0. 0009 mSv. Mean effective radiation doses of study group A and B were significantly lower than the control group (P < 0.001). Study group A and control group images showed no significant difference in image quality except for some anatomic landmarks. Study group B images had lower image quality than control group images.
Conclusions
Temporal bone CT with 135 kVp and 5 mAs can be performed at very low radiation exposure while maintaining high image quality.
Get full access to this article
View all access options for this article.
References
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
