腹主动脉瘤术前CT血管造影重建方法的选择

The choice of multi slice computer tomography angiography reconstruction methods in the pre-operative abdominal aortic aneurysms

目的探讨综合应用CT血管造影（CTA）多种重建方法对腹主动脉瘤（AAA）腔内隔绝术术前腹主动脉瘤测量影像学评估的价值。方法回顾分析2009年6月至2011年3月共100例AAA多排螺旋CT血管造影（MSCTA）资料，并分析其中83例成功实施主动脉腔内修复术（EVAR）患者的MSCTA影像学资料，应用容积再现、多平面重建、最大密度投影和曲面重建分别测量EVAR术相关各解剖学数据，并对照单纯应用轴位影像数据测量，比较各测量值之间的差异。结果15例（15．0％）行外科腹主动脉人工血管置换术，2例（2．0％）临床定期随诊，未行手术治疗，83例（83．0％）行EVAR术治疗。行EVAR术治疗的83例患者中，Ⅰ型2例（2．4％）；Ⅱ型66例（79．5％），其中Ⅱa型35例、Ⅱb型18例、ⅡC型13例；Ⅲ型15例（1t．1％）。对比83例行EVAR术病例的MSCTA不同重建方法与轴位测量间数据，近端瘤颈长度、瘤体长度、髂总动脉长度，远端瘤颈长度、近端瘤颈内径、远端瘤颈内径、髂总动脉内径等各测量值差异有统计学意义。单纯应用轴位成像测量，会高估血管内径线，而对长度测量则会导致低估。结论单纯应用轴位影像或仅根据DSA测量数值均会导致较大的测量误差，应综合应用MSCTA多种重建方法直观显示AAA的形态学变异、腔内精确结构及分支血管关系，精确测量AAA与治疗相关的主要径线，为临床治疗方法的选择提供有力依据。

Objective To assess the clinical value of integrated applications of multi slice computer tomography angiography （MSCTA） and multiple reconstruction methods in pre-operative abdominal aortic aneurysms. Methods The MSCTA data of 100 abdominal aortic aneurysms（AAA） from June 2009 to March 2011 were analyzed retrospectively. And the parameters that endovascular aortic repair（EVAR） required were measured by volume rendering techique, mulit-planar reformation, maximum intensity projection and curved planar reformation reconstruction seperately in 83 eases which had underwent EVAR successfully. Compared with single axis view of measure- ments, the differences between MSCTA different reconstruction methods were assessed. Results Traditional surgeries were performed in 15 cases, clinical follow up were performed in 2 eases, and EVAR were performed in 83 cases. In 83 eases which underwent EVAR, 2 cases were type Ⅰ（2.4%）, 66 eases were type Ⅱ（79.5%） ,in which 35 cases were type Ⅱ a, 18 cases were typeⅡb, 13 cases were type Ⅱe, and 15 cases were type Ⅲ（18.1% ）. The parameters including the length and diameter of proximal and distal neck, the bilateral common iliae arteries, the diameter of bilateral external iliac arteries, the length of aneurysm, and the angles were measured in MSCTA. Compared with the single axis view of measurements, there was significance differences. Conclusions The abdominal aortic aneurysm measured by single axis view can lead to an error measurements of length. The integrated applications of MSCTA and multiple reconstruction methods can describe the details of AAA.