A phantom study using dual-energy spectral computed tomography imaging: Comparison of image quality between two adaptive statistical iterative reconstruction (ASiR, ASiR-V) algorithms for evaluating ground-glass nodules of the lung

• Published in: Journal of cancer research and therapeutics Vol. 17; no. 7; pp. 1742 - 1747
• Main Authors: Li, Jun, Gao, Jun, Wang, Guangli, Cui, Dingye, Deng, Kai
• Format: Journal Article
• Language: English
• Published: India Wolters Kluwer India Pvt. Ltd 01.12.2021; Medknow Publications and Media Pvt. Ltd; Medknow Publications & Media Pvt. Ltd
• Subjects: Algorithms; Comparative analysis; CT imaging; Diagnosis; Humans; Image processing; Lung - diagnostic imaging; Lung tumors; Methods; Noise; Radiation Dosage; Radiographic Image Interpretation, Computer-Assisted - methods; Signal-To-Noise Ratio; Tomography; Tomography, X-Ray Computed - methods; China; computed tomography; image quality; pulmonary nodules; spectral computed tomography; Adaptive statistical iterative reconstruction
• ISSN: 0973-1482; 1998-4138; 1998-4138
• DOI: 10.4103/jcrt.JCRT_1780_20

Aims: To assess the image quality of the two adaptive statistical iterative reconstruction (ASiR and ASiR-V) algorithms for evaluating ground-glass nodules (GGNs) of the lung. Subjects and Methods: The chest phantom with ground-glass simulated pulmonary nodules was scanned by dual-energy spectral computed tomography (CT) using gemstone spectral imaging mode. The image was reconstructed with ASiR and ASiR-V from 0 (FBP) to 90% blending percentages, respectively. The average noise and signal-to-noise ratio (SNR) of reconstruction images were calculated. The data were statistically analyzed. Results: Compared with FBP, as the percentage of ASiR and ASiR-V increased from 10 to 90%, image noise reduced by 3.7%-45.2% and 14.1%-73.8%, respectively, and the SNR increased accordingly. There was significantly higher SNR value of ASiR-V images as the percentages of IR increased to 50% or greater, compared to those of ASiR. Subjective image quality scores of ASiR and ASiR-V improved significantly as percentage increased from 10 to 80% for ASiR and ASiR-V (peaked at 60% for both of them). Conclusions: Both ASiR and ASiR-V can reduce the image noise and improve the objective image quality for presenting pulmonary nodules on dual-energy spectral CT imaging compared with FBP. ASiR-V provided further image quality improvement than ASiR, and both ASiR and ASiR-V 60% had the highest image quality score.