Institutional members access full text with Ovid®

Share this article on:

Performance of Iterative Reconstruction and Automated Tube Voltage Selection on the Image Quality and Radiation Dose in Abdominal CT Scans

Desai, Gaurav S. MD; Fuentes Orrego, Jorge M. MD; Kambadakone, Avinash R. MD; Sahani, Dushyant V. MD

Journal of Computer Assisted Tomography: November/December 2013 - Volume 37 - Issue 6 - p 897–903
doi: 10.1097/RCT.0b013e3182a73fa6
Abdominal CT Techniques and Dose Optimization

Objective To study the impact of sinogram-affirmed iterative reconstruction (SAFIRE) and concurrent application of automated tube voltage selection (ATVS) on image quality (IQ) and radiation dose.

Methods A phantom was scanned using various computed tomography (CT) parameters (kV, 80–120; mAs, 50–200). Abdomen contrast-enhanced CT (CECTs) in 170 adults were performed using dose-modified protocols: in 145 patients (group I), ATVS was applied (mAs, 111–649); in 25 (group II), the kV was fixed at 120 (reference mAs, 150). In 95 patients, standard-dose (SD) scan was available. Two readers evaluated the IQ of filtered back projection (FBP) and SAFIRE (levels 1, 3, and 5) images.

Results In phantom, nonlinear drop in noise with increasing strengths of IR (levels S1–S5) was noted. The dose-modified IR scan was rated diagnostic in all 170 patients, with IQ score comparable to that of SD-FBP (P = 0.3). Lower kV (100/80) was prescribed by ATVS in 70% examinations in group I. In comparison with SD-FBP, the mean dose in CT dose index in group I (IR, 3.2 mGy; SD-FBP, 13.02 mGy; P < 0.0001) and in group II (IR, 4.8 mGy; SD-FBP, 11.8 mGy; P < 0.001) was 75.4% and 59.3% lower.

Conclusions Use of SAFIRE and ATVS provides diagnostic quality images at 59.3% to 75.4% reduced dose compared with SD-FBP scan.

From the Department of Radiology, Division of Abdominal Imaging and Intervention, Massachusetts General Hospital, Harvard Medical School, Boston, MA.

Received for publication May 2, 2013; accepted July 19, 2013.

Reprints: Dushyant Sahani, MD, Division of Abdominal Imaging and Intervention, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114 (e-mail: dsahani@partners.org).

The study was not funded by any agency or CT manufacturer.

The authors report no conflicts of interest.

Copyright © 2013 Wolters Kluwer Health, Inc. All rights reserved.