Effect of reconstructed slice thickness on the display of hepatocellular carcinoma in virtual non-contrast scan of dual-layer detector spectral CT(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2022年第12期
- Page:
- 1495-1501
- Research Field:
- 医学影像物理
- Publishing date:
Info
- Title:
- Effect of reconstructed slice thickness on the display of hepatocellular carcinoma in virtual non-contrast scan of dual-layer detector spectral CT
- Author(s):
- XIE Mengzhen; WU Bin; XU Liqiang; LIU Yubao; WANG Jindian; ZHAO Yanbo; GAO Junwen
- Medical Imaging Center, Shenzhen Hospital of Southern Medical University, Shenzhen 518110, China
- Keywords:
- Keywords: hepatocellular carcinoma dual-detector spectral CT virtual non-contrast scan radiation dose
- PACS:
- R816.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2022.12.007
- Abstract:
- Abstract: Objective To explore the optimal slice thickness for virtual non-contrast scan (VNC) of dual-layer detector spectral CT of hepatocellular carcinoma (HCC). Methods The imaging data of abdominal CT scan of 73 HCC patients were analyzed retrospectively. The true non-contrast (TNC), arterial VNC (VNC-a) and portal VNC (VNC-p) images with the slice thickness of 5, 3 and 1 mm were evaluated and compared in terms of CT number, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and noise (SD). The consistency of the CT number between TNC image and VNC image was analyzed using Bland Altman plot scatter diagram, and the image quality was evaluated using 5-point method. Results Compared with TNC images, VNC-a and VNC-p images of different slice thicknesses had higher SNR and lower SD (P<0.05), but there was no statistical difference in CT number and CNR (P>0.05). The pairwise comparison within the group revealed that VNC-p images with the slice thickness of 5 and 3 mm had lower SD and higher SNR than VNC-a images (P<0.05), and that for the slice thickness of 1 mm, SD and SNR were close in VNC-p image and VNC-a image (P>0.05). For the slice thicknesses of 5 and 3 mm, the CT numbers of VNC-a image, VNC-p images and TNC images were in good consistency, of which 3 mm VNC-p image has the lowest proportion of data points outside the LOA (1.4%) and had the best consistency with TNC. The subjective score of 1 mm VNC-p images was the highest among all images. For 1 mm slice thickness, the subjective score of VNC-p image was significantly higher than TNC image and VNC-a image (P<0.05) for VNC-p images, the image with 1 mm slice thickness significantly higher than those with 5 and 3 mm slice thicknesses (P<0.05). Cancellation of TNC and direct enhanced scan reduced the radiation dose by 34.57%. Conclusion The application of VNC of double-layer detector spectral CT is affected by slice thickness. VNC-p image with the slice thickness of 3 mm has the highest consistency in CT number, the lowest SD and the highest SNR, which can be used for objective measurement and VNC-p image with the slice thickness of 1 mm shows the best outline and details of the lesion, and can be used for subjective evaluation.
Last Update: 2022-12-23