Wang Aimin,Tang Kun,Li Rui, et al. Imaging quality optimization of CT cerebral angiography by using single source spectral CT[J]. JOURNAL OF WEZHOU MEDICAL UNIVERSITY, 2016, 46(8): 600-603.
Abstract：Objective: To determinate the optimal keV levels of single source spectral CT by evaluating imaging qualities of CT cerebral angiography. Methods: A total of 53 cases underwent spectral CT were enrolled in this study. All images of cerebral angiography were reconstructed by software of spectral CT from 40 to 140 keV in 10 keV increments. The mean vessel attenuation and the contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR) of the following arteries: basilar artery, internal carotid artery, anterior cerebral artery, middle cerebral artery and posterior cerebral artery were measured and calculated respectively. Subjective assessment on imaging quality was performed by using a 5-point scoring system. The results of objective image quality among different keV levels were compared using one-way analysis of variance. For subjective assessment, the Nonparametric Wilcoxon test was used to analyze the differences in subjective scores. Results: The image noise at 70-140 keV levels was statistically lower than that at 40, 50 and 60 keV levels. The image CNR and SNR between 60 keV and 70 keV levels showed on statistically differences, but markedly higher than other keV levels (P<0.05). The scores of subjective image quality at 70 keV level were all higher than other keV levels including 60 keV level (P<0.05). Conclusion: The 70 keV level can be commended as an optimal keV setting for spectral CT cerebral angiography by improving image CNR, SNR and reducing image noise.
