Impact of Model-Based Iterative Reconstruction on Image Quality of Contrast-Enhanced Neck CT

Abstract

BACKGROUND AND PURPOSE: Improved image quality is clinically desired for contrast-enhanced CT of the neck. We compared 30% adaptive statistical iterative reconstruction and model-based iterative reconstruction algorithms for the assessment of image quality of contrast-enhanced CT of the neck.

Advanced Modeled Iterative Reconstruction in Low-Tube-Voltage Contrast-Enhanced Neck CT: Evaluation of Objective and Subjective Image Quality

“…Similar findings were reported by Gaddikeri et al 12 for modelbased iterative reconstruction compared with FBP in 140-kVp contrast-enhanced neck CT. Thus, the lower part of the neck remains a critical area to evaluate when applying dose-saving scan protocols, and application of these protocols should be considered on the basis of the indication for imaging.…”

“…[4][5][6] The interaction of these parameters is complex, and manual adjustments may result in nondiagnostic images. Thus, commercially available techniques, including tube current modulation, 7 automatic exposure control, 8,9 automated tube voltage adaptation, 10,11 iterative reconstruction, [12][13][14][15] and selective in-plane shielding (thyroid, eye lens, breast, and gonads), 16 have been introduced to support the radiologic technologist, physicist, and radiologist team in developing appropriate CT protocols. Reduced tube voltage can increase contrast-to-noise ratio (CNR) of iodine enhancing soft-tissue structures, while the radiation dose is substantially reduced.…”

“…4 The drawback of an increased image noise in low-tube-voltage examinations can be counteracted by iterative reconstruction, which reduces image noise compared with filtered back-projection (FBP). 12,14 Recently introduced advanced modeled iterative reconstruction (ADMIRE) performs detailed modeling in the projection data domain, result-ing in less noise and improved artifact suppression. 17 ADMIRE includes a local signal-to-noise relationship analysis and decomposes the image data into information and noise.…”

“…Gaddikeri et al 12 recently reported a substantial image noise reduction and increased SNR and CNR in 140-kV contrast-enhanced neck CT by using model-based iterative reconstruction compared with FBP. Nevertheless, image acquisition with 100 or 120 kV is more commonly encountered due to a lower radiation dose and improved iodine attenuation.…”

“…Prior studies have reported that the combination of a reduced tube voltage and an iterative reconstruction algorithm may allow substantial radia- tion dose reduction without impairment of image quality. [12][13][14]26 Third-generation DSCT has improved tube efficiency at lower tube voltages and is equipped with a model-based ADMIRE algorithm to provide adequate image quality in low-tube-voltage acquisitions. ADMIRE has been shown to provide an improved 3D regularization process, which results in better noise reduction in the image domain.…”