CAJ | 학술논문

目的研究新双源CT的虚拟平扫技术在肝脏扫描中的应用价值.方法 51例肝脏CT平扫和增强扫描患者在完成常规平扫、肝动脉期及门静脉期3期扫描后,采用肝脏虚拟平扫后处理软件生成虚拟平扫图像.采用Wilcoxon分析比较常规平扫和虚拟平扫图像的病灶显示,并利用t检验对比分析肝脏、肌肉的CT值、图像SNR,以及患者单期扫描时接受的辐射剂量和总辐射剂量容积CT剂量指数(CTDIvol)值和剂量长度乘积(DLP)值.结果虚拟平扫和常规平扫在病灶显示上无明显差异.虚拟平扫肝脏CT值(61.32±6.04)HU,大于常规平扫的(56.85±4.80)HU,差异有统计学意义(t=-3.927,P＜0.01);虚拟平扫图像SNR 11.28±2.78,大于常规平扫的8.65±1.56,差异有统计学意义(t=-5.590,P＜0.01).虚拟平扫CTDIvol总量(14.35±1.66)mGy和DLP总量(313.91±45.08)mGy·cm均低于常规平扫的(21.43±2.46)mGy和(469.02±66.22)mGy·cm,差异均有统计学意义(t值分别为16.168和13.132,P值均＜0.01).结论新双源CT的虚拟平扫技术在保证图像质量的前提下降低了辐射剂量,使其取代常规平扫成为可能.
목적 연구신쌍원CT적허의평소기술재간장소묘중적응용개치.방법 51례간장CT평소화증강소묘환자재완성상규평소、간동맥기급문정맥기3기소묘후,채용간장허의평소후처리연건생성허의평소도상.채용Wilcoxon분석비교상규평소화허의평소도상적병조현시,병이용t검험대비분석간장、기육적CT치、도상SNR,이급환자단기소묘시접수적복사제량화총복사제량용적CT제량지수(CTDIvol)치화제량장도승적(DLP)치.결과 허의평소화상규평소재병조현시상무명현차이.허의평소간장CT치(61.32±6.04)HU,대우상규평소적(56.85±4.80)HU,차이유통계학의의(t=-3.927,P＜0.01);허의평소도상SNR 11.28±2.78,대우상규평소적8.65±1.56,차이유통계학의의(t=-5.590,P＜0.01).허의평소CTDIvol총량(14.35±1.66)mGy화DLP총량(313.91±45.08)mGy·cm균저우상규평소적(21.43±2.46)mGy화(469.02±66.22)mGy·cm,차이균유통계학의의(t치분별위16.168화13.132,P치균＜0.01).결론 신쌍원CT적허의평소기술재보증도상질량적전제하강저료복사제량,사기취대상규평소성위가능.
Objective To assess the virtual non-contrast liver CT from dual-energy CT for the clinical application. Methods In total, 51 patients were included in the study, and all patients underwent multi-phase liver CT on a dual-source CT. The True non-contrast liver CT (TNCT) was performed in a single-energy acquisition mode, but the arterial and portovenous liver CT (VNCT) were performed in a dual-energy mode of 110 kV and 140 kV respectively. The virtual non-contrast CT images were derived from the arterial data using liver virtual non-contrast software. Between the true non-contrast CT and the virtual non-contrast CT, the image quality, mean CT HU values in the liver and muscle, signal to noise (SNR), the radiation dose of volume CT dose index (CTDIvol) and dose length product (DLP) in a single phase and total examination were compared with t test. Results There was no significant difference in the detection of liver lesions between TNCT and VNCT. The CT Hu values of muscle on both TNCT and VNCT images were almost equal. The CT HU values of liver on VNCT images were higher than that on TNCT images and the difference was significant [61.32 ±6. 04 vs. (56. 85 ±4. 80) HU, t = -3. 927,P＜0.01]. There was also significant differenc of SNR between TNCT (11.28±2. 78) and VNCT (8.65 ± 1.56) images( t =-5.590,P＜0.01). The CTDIvol and DLP of single phase were (7.07 ±0.85) mGy and (155.11 ±respectively, but in TNCT the total CTDIvol and DLP reached (21.43 ± 2. 46 ) mGy and (469. 02 ±significance, but the total CTDIvol and DLP were significantly different (t = 16. 168 and 13. 132, P ＜0. 01). Conclusion With the consequent reduction in radiation dose, the VNCT can replace TNCT as an imaging protocol in multi-phase abdominal CT examination in clinic.