双能量CT虚拟平扫在颈部扫描中的应用价值OACSTPCD

Objective:To explore the image quality and radiation dose of virtual non-contrast(VNC)dual-energy CT(DECT)in neck CT examination.Methods:A total of 49 patients who underwent true non-contrast(TNC)DECT were retrospectively collect-ed.Objective image quality(submandibular gland,thyroid gland,sternocleidomastoid muscle,internal jugular vein,fat,cervical vertebra and tracheal gas),noise,signal-to-noise ratio(SNR),and subjective score were compared between TNC and VNC images.The radiation dose including volume CT dose index(CTDIvol),dose length product(DLP)and effective dose(ED)were com-pared between TNC DECT and single DECT.Results:No signif-icant differences in CT values of submandibular gland,internal jugular vein,sternocleidomastoid muscle and tracheal gas were found between VNC and TNC images(all P>0.05).Compared with TNC image,the CT values of thyroid gland and cervical vertebra in VNC image was significantly lower,while the CT value of fat in VNC image was significantly higher(all P<0.05).There were no signif-icant differences between VNC and TNC in noise[(2.80±1.28)HU vs(2.60±0.79)HU,t =-0.901,P>0.05]and SNR(25.14±9.85 vs 26.36±9.46,t = 0.630,P>0.05).DECT was significantly lower than TNC DECT in CTDIvol[(7.48±0.33)mGy vs(19.67±1.21)mGy,t = 68.808,P<0.05],DLP[(194.06±22.90)mGy.cm vs(503.82±66.11)mGy.cm,t = 31.308,P<0.05]and ED[(0.41±0.05)mSv vs(1.06±0.14)mSv),t = 31.308,P<0.05].Conclusion:VNC imaging can guarantee approx-imately comparable image quality as TNC imaging,and reduce the radiation dose of neck DECT.