The Value Of Monochromatic Reconstruction Imaging Of Gemstone Energy Spectrum CT In Evaluation Of Hypovascular Small Metastases Of Liver

Objective:To explore the use of gem-spectral CT?GSCT?monochromatic reconstrection?MR?imaging to improve the image quality and its application value to hypovascular metastases of liver.Methods:46 patients with hepatic metastases were collected,that had 116 hypovascular lesions.All the patients contrast enhanced scanned on GSCT.At each phase of arterial?portal and delayed,calculate the contrast of liver metastases to liver parenchyma?C?and diference of liver metastases and liver parenchyma iodine concentration?IC?.According to median of diference choose the suitable phase for detection hypovascular liver metastases.Reconstruct 11 groups of monochromatic reconstruction?MR?and polychromatic reconstruction?PR?image during suitable phase.Acoording to C and CNR of liver metastases,the best MR was selected from 11 MRs.2practicedness doctors subjectivly evaluate image quality of best MR and PR in 5points.The best MR's objective indicators and subjective score compared with PR.Another 2 senior doctors independently interpret the best MR image and PR,and record each lesion according to the 5-point reliability method.Paired chi-square test was used to analyze the difference of the coincidence rate between PR and MR₆₀.The t-test was used to compare quantitative indexes such as lesion diameter and CNR in the consistent and inconsistent groups of PR and MR₆₀0 results.Results:The median of C and differenc of IC at arterial?portal and delayed phase were different?P<0.001?,The medians of portal pahase were highest.MR₆₀0 CNR,subjective score,and detection rate were higher than PR?P<0.05?,and there were significant differences in lesions with a diameter of<10mm?P<0.05?.Conclusion:Compared with PR,MR₆₀0 improves the image quality and the detection rate of hypovascular liver metastases,and has a better detection rate for small lesions.