家兔肝脏低剂量CT灌注成像的可行性研究

目的:探讨低剂量CT灌注成像对家兔肝脏灌注成像参数及图像质量的影响。方法:对9只家兔行常规剂量、中等剂量和低剂量肝脏CT灌注成像,对图像进行后处理,测量肝脏灌注参数值,包括肝血容量(BV)、肝血流量(BF)、肝动脉灌注量(APL),并对获得的肝脏灌注图进行主观质量评分,对3组灌注参数值和图像质量评分进行统计学分析。同时记录三种条件下的辐射记录值。结果:低剂量组、中等剂量组和常规剂量组的BF、BV、APL值差异无统计学意义(P>0.05)。低剂量组、中等剂量组和常规剂量组图像主观评分分别为(4.11±0.65)分、(4.38±0.61)分和(4.56±0.58)分,2名医师观察者间一致性较好(Kappa值为0.507)。低剂量组所接受辐射剂量远低于常规记录,容积CT剂量指数(volume CT dose index,CTDIvol)和剂量长度乘积(dose length product,DLP)均下降了75%。结论:基于降低管电流方式的家兔肝脏低剂量CT成像是可行的。

The feasibility study of hepatic low-dose CT perfusion imaging in rabbit

Objective:To explore the effect of hepatic lose-dose CT perfusion imaging for perfusion parameters and image qual-ity. Methods:9 rabbits were undergone routine dose,median dose and low-dose CT perfusion scanning. The original images were pro-cessed by perfusion software. The value of blood volume ( BV) ,blood flow ( BF) and arterial liver perfusion ( ALP) were measured and image quality were evaluated, and statistical analysis was performed. Results:The differences of BF, BV, and ALP among the three groups were not statistically significant (P>0. 05). The scores of image quality in routine dose group,median dose group and low-dose group were 4. 11 ± 0. 65,4. 38 ± 0. 61 and 4. 56 ± 0. 58,respectively. The two reviewers keep good consistency. Kappa value of two re-viewers was 0. 507. Compared with the routine dose group,the value of CTDIvol and DLP of the low-dose group decreased 75%. Con-clusion:Low-dose hepatic CT perfusion imaging based on reducing tube current in rabbit was feasible.