In vitro analysis of gallstone composition with spectral CT / 中国医学影像技术

ABSTRACT

Objective: To explore the value of spectral CT in differentiating pure and impure cholesterol stones. Methods: Spectral CT was used to scan in vitro gallstones, and infrared spectroscopy spectrum was used to observe the composition and classification of gallstones. ROIs were outlined in the axial, coronal and sagittal maximum planes of gallstones. Spectral CT indexes, including spectral curves, CT value, CT slope, effective atomic number (Zeff) and calcium-water ratio (CWR)) of the stones were acquired. Mann-Whitney U test was used to analyze the differences of parameters among different gallstone groups and subgroups. ROC curve was used to determine the diagnostic threshold, sensitivity, specificity, positive predictive value and negative predictive value of pure and impure cholesterol stone group. Results: There were significant differences of CT parameters between pure and impure cholesterol stone groups (all P0.05). Conclusion: The parameters of pure and impure cholesterol stones have good diagnostic efficacies. There are differences of energy spectrum curves of gallstones with different compositions.