Monochromatic energy images from spectral CT in diagnosing X-ray negative biliary stones
10.3760/cma.j.issn.1007-8118.2016.07.009
- VernacularTitle:能谱CT单能量成像诊断胆道系统X线阴性结石
- Author:
Peipei XIE
;
Weiling XUAN
;
Jianping DING
- Publication Type:Journal Article
- Keywords:
Spectral CT;
Biliary X-ray negative stone;
Monochromatic energy images;
Biliary calculi;
Diagnosis
- From:
Chinese Journal of Hepatobiliary Surgery
2016;22(7):460-463
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the role of monochromatic energy images from spectral CT in diagnosing X-ray negative biliary stones.Methods 32 patients who were diagnosed to have X-ray negative biliary stones were retrospectively studied.They were examined by spectral CT scanning and the spectral CT data were loaded into a spectrum analysis software.The optimal contrast-to-noise ratio (CNR) of the monochromatic energy images were exposed and the contrast ratio between the X-ray negative stones and bile on the optimal monochromatic and hybrid energy CT images were compared,respectively.The monochromatic and hybrid energy CT images for diagnosing X-ray negative biliary stones were validated by two senior radiologists based on postoperative histology.Results The corresponding KeV of optimal CNR for X-ray negative stones were not quite consistent.They were 140KeV in 19 patients,40KeV in 8 patients,53KeV,57KeV,62KeV,64KeV and 73KeV in one patient each.The contrast between the negative stones and the adjacent bile were (6.4 ±5.6) HU on hybrid energy CT images and (50.4 ±24.4) HU on optimal monochromatic energy CT images.The Eff-Z of negative stones and bile were 6.6 ± 0.6 and 7.9 ± 0.2,respectively.In our study,the diagnostic accuracy of hybrid energy CT images was 34.38% and that of optimal monochromatic energy CT images was 78.13%.Conclusion The optimal monochromatic energy CT images were more valuable in diagnosing X-ray negative bile duct stones,which were obviously better than the hybrid energy images from traditional CT.