![]() ![]() Except for the smallest airway, MBIR enabled significant reduction in both the relative bias and angular standard deviation of the WT, particularly at low radiation dose levels the SSQ was reduced by 50%-96% by using MBIR. For FBP, the relative bias and the angular standard deviation of the measured WT increased steeply with decreasing radiation dose. Compared with FBP, MBIR improved the CNR of the airways, particularly at low radiation dose levels. Finally, the particular kV-mAs combination and reconstruction algorithm that minimized radiation dose while still achieving a reference WT quantification accuracy level was chosen as the optimal acquisition and reconstruction settings.The wall thicknesses of seven airways of different sizes were analyzed in the study. For each airway and reconstruction algorithm, the overall performance of WT quantification across all of the 20 kV-mAs combinations was quantified by the sum of squares (SSQs) of the difference between the measured and nominal WT values. For each kV-mAs combination and each reconstruction algorithm, the contrast-to-noise ratio (CNR) of the airways was measured, and the WT of each airway was measured and compared with the nominal value the relative bias and the angular standard deviation in the measured WT were calculated. Both FBP and a commercial implementation of MBIR (Veo(TM), GE Healthcare) were used to reconstruct CT images of the airways. The purpose of this work was to study the impact of radiation dose and MBIR in the MDCT assessment of airway WT.An airway phantom was scanned using a clinical MDCT system (Discovery CT750 HD, GE Healthcare) at 4 kV levels and 5 mAs levels. The recent commercial implementation of the statistical model-based iterative reconstruction (MBIR) algorithm, instead of the conventional filtered back projection (FBP) algorithm, has enabled considerable radiation dose reduction in many other clinical applications of MDCT. Multidetector computed tomography (MDCT) has recently been used to evaluate airway WT, but the potential risk of radiation-induced carcinogenesis-particularly in younger patients-might limit a wider use of this imaging method in clinical practice. Wall thickness (WT) is an airway feature of great interest for the assessment of morphological changes in the lung parenchyma. Vice Provost for Undergraduate Education.Office of Vice President for Business Affairs and Chief Financial Officer.Office of VP for University Human Resources.Stanford Woods Institute for the Environment.Stanford Institute for Economic Policy Research (SIEPR). ![]() Institute for Stem Cell Biology and Regenerative Medicine.Institute for Human-Centered Artificial Intelligence (HAI).Institute for Computational and Mathematical Engineering (ICME).Freeman Spogli Institute for International Studies.Stanford Doerr School of Sustainability. ![]()
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