Impact of hybrid iterative reconstruction on unenhanced liver CT

• Published in: British journal of radiology 2017-02, Vol.90 (1070), p.20150670-20150670
• Main Authors: Kondo, Masatoshi, Nishie, Akihiro, Fujita, Nobuhiro, Morita, Koichiro, Shirasaka, Takashi, Arimura, Hisao, Nakamura, Yasuhiko, Honda, Hiroshi
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Carcinoma, Hepatocellular - diagnostic imaging; Female; Humans; Liver - diagnostic imaging; Liver Neoplasms - diagnostic imaging; Male; Middle Aged; Physics and Technology; Radiographic Image Interpretation, Computer-Assisted - methods; Reproducibility of Results; Retrospective Studies; Tomography, X-Ray Computed - methods
• ISSN: 0007-1285; 1748-880X
• DOI: 10.1259/bjr.20150670

To clarify the impact of hybrid iterative reconstruction (HIR) and filtered back projection (FBP) on unenhanced liver CT. 30 patients with hepatocellular carcinoma (HCC) underwent unenhanced CT. The images were reconstructed with FBP and weak (Level 1), mild (Level 4) and strong (Level 7) levels of HIR (iDose ; Philips Medical Systems, Cleveland, OH). Quantitatively, attenuations of the HCC (with the largest lesion in each case), hepatic parenchyma (the average of four segments) and image noise (standard deviation of the attenuations in hepatic parenchyma) were compared between the four kinds of reconstruction using the two-tailed paired t-test. Qualitatively, liver lesion conspicuity and characterization were also compared using the Wilcoxon signed-rank test. Attenuation of the liver lesion with the strong level of HIR was significantly higher than that with FBP (p = 0.0005). Attenuations of hepatic parenchyma with all three HIR levels were significantly lower than that with FBP (p ≤ 0.0002 in all comparisons). Image noise with each of the three HIR levels was significantly smaller than that with FBP (p