正常肝脏CT灌注成像技术及灌注参数图像重建方法探讨  

CT Perfusion Imaging Technology and the Image Reconstruction Method of Perfusion Parameters

作　　者：王守安[1] 白人驹[2] 孙浩然[2] 征锦[1] 

机构地区：[1]扬州大学临床医学院江苏省苏北人民医院CT室,江苏扬州225001 [2]天津医科大学总医院放射科

出　　处：《实用放射学杂志》2007年第3期342-346,共5页Journal of Practical Radiology

摘　　要：目的 探讨肝脏CT灌注成像扫描程序、灌注参数计算和灌注参数图像重建方法。方法 对30例无任何肝脏疾病的正常肝脏进行同层动态增强扫描，用最大斜率法进行肝脏CT灌注参数的计算，利用去卷积法的图像重建功能，经改进后进行肝脏CT灌注参数图像的重建，重建出肝动脉灌注量（HAP）、门静脉灌注量（PVP）、肝动脉灌注指数（HPI）及门静脉灌注指数（PPI）等4种图像。结果 最大斜率法计算的正常肝脏CT灌注参数：HAP、PVP、全肝总灌注量（TLP）、HPI、PPI分别为（0．3355±0．1269）ml·min^-1·ml^-1、（1．1034±0．2065）ml·min·ml^-1、（1．4389±0．2398）ml·min^-1·ml^-1、（23．3±10．2）％、（76．7±10．2）％；在重建出的HAP图像上，肝实质呈中等程度的灌注，在PVP图上肝实质呈明显均匀高灌注，在HPI和PPI图上的表现分别与HAP和PVP类似。在重建图像上测得的HAP、PVP、HPI、PPI分别为（0．3489±0．12）ml·min^-1·ml^-1、（1．2084±0．37）ml·min^-1·ml^-1、（22．41±8．31）％、（77．59±8．31）％，并据HAP、PVP计算出的TLP为（1．5573±0．42）ml·min^-1·ml^-1，与最大斜率法结果比较均无显著性差别。结论 采用1次屏气，注射40-50ml对比剂，注射速度为4—5ml·s^-1，从注射对比剂后7—9s开始连续扫描45s共45层的扫描方式，基本能反映各组织结构的血液动力学变化过程，是较理想并实用的扫描方案；采用改进后重建方法重建出的灌注参数图像，能直观地反映肝脏的血流灌注特征，是一种简单实用的灌注图像重建方法，值得进一步临床应用和推广。Objective To explore a optimal CT scanning sequence , the calculation method of perfusion parameters and the image reconstruction method of perfusion parameters of liver. Methods Perfusion CT was performed in thirty volunteers, five perfusion parameters such as HAP , PVP , TLP , HPI,PPI were obtained with maximum slope method,four images such as HAP,PVP,HPI,PPI were reconstructed with modified - deconvolution method. Results HAP,PVP,TLP,HPI,PPI of normal liver were （0.3355±0. 1269）ml · min^-1 · ml^-1 , （ 1. 1034 ± 0. 2065 ） ml^-1· min^ -1· ml^ - 1, （ 1. 4389 ± 0. 2398 ） ml · min^ - 1· ml^ -1 , （ 23.3 ± 10.2 ） % , （ 76.7 ± 10.2 ） % respectively. Normal parenehyma appeared as intermediate perfusion at the HAP image, and as high perfusion at the PVP image, the appearance of which at the HPI image and the PPI image were similar to that at the HAP image and the PVP image respectively. HAP ,PVP,HPI and PPI measured at the reconstructed images were （ 0.3489 ± 0.12 ） ml · min ^- 1 · ml^ -1, （ 1. 2084 ± 0.37 ） ml · min^ -1 · ml^ - 1, （ 22.41 ± 8.31 ） % and （ 77.59 ± 8.31 ） % respeetively,TLP calculated by HAP, PVP were （ 1. 5573 ± 0.42 ） ml ·min ^-1 · ml ^- 1. The resultes had not obvious difference compared with that of maximum slope method. Conclusion The method of CT scanning that a single slice through the portal hepatis is repeatedly scanned for 45 s during a single breath - holding after 7 - 9 s of intravenous bolus injection of 40 - 50 ml nonionie contrast media at a rate of 4 - 5 ml · s^ -1 is a optimal and practical scanning method of hepatic CT perfuion, by which the process of hemodynamie change of tissue and structure can be approximately reflected. The perfusion parameter images reconstructed by modified - deeonvolution method can directly display the perfusion character of blood flow of normal liver,so this method is a simple and practical CT perfusion image reeonstraetion method, it is worth for further clinical application and widely spread.

关 键 词：肝脏 体层摄影术 X线计算机 灌注成像 

分 类 号：R322.47[医药卫生—人体解剖和组织胚胎学] R814.42[医药卫生—基础医学]