多层螺旋CT三维血管成像在颅内动脉瘤评价中的初步应用--与DSA的对比研究

目的通过与数字减影血管造影(DSA)的对比研究，初步探讨三维CT血管成像(3D—CTA)在颅内动脉瘤评价中的应用价值。资料与方法对24例临床疑有颅内动脉瘤患者进行3D—CTA和DSA。3D—CTA后处理技术包括多平面重建(MPR)、最大信号强度投影(MIP)以及容积重建(VRT)。3D—CTA和DSA分别由相互独立的放射科医师实施和诊断，分别记录动脉瘤的位置、大小、形态以及与周围动脉分支等的关系。同时调查神经外科医师及患者对两种影像手段的认可度。结果3D—CTA发现13例15个动脉瘤，遗漏1个直径1．2mm的动脉瘤，发现的最小动脉瘤长径为1.8mm。DSA发现14例16个动脉瘤。CTA在显示瘤颈以及相邻骨质结构上明显优于DSA，而DSA空间分辨率较高。神经外科医师多认为CTA可以用作颅内动脉瘤的筛查和术前评估，而DSA仍是金标准。患者对CTA的接受度较高。结论3D—CTA是检查颅内动脉瘤高度敏感的无创影像手段，它可以作为颅内动脉瘤筛查和术前评估的首选技术。

Evaluation of Intracraninal Aneurysms with Three Dimensional CT Angiography: Comparison with Digital Subtraction Angiography

Objective To evaluate the value of three dimensional spiral CT angiography (3DCTA) in the detection and characterization of intracranial aneurysms, compared with DSA.Materials and Methods 24 patients who suspected as harboring intracranial aneurysms by referring physicians were underwent both 3DCTA and conventional DSA. 3D postprocessing techniques included MPR, MIP and VRT. 3D-CTA and DSA were performed and reviewed by two independent blinded radiologists. The presence, location, size, and shape of the detected aneurysms were outlined. Presence of a neck and relationship of the aneurysm to adjacent arterial branches was also configured. Neurosurgeons and patients were surveyed about the preference of imaging criteria for preoperative evaluation. Results In our series, a total of 15 aneurysms were found in 13 patients via DSA, and 1 aneurysm with the diameter of 1.2 mm was missed in CTA. The minimum diameter of aneurysm detected by CTA was 1.8 mm. 16 aneurysms in 14 patients were found by DSA. Depiction of the neck and adjacent structures by CTA were significantly better than DSA, but DSA had higher spatial resolution. Neurosurgeons prefer CTA as a screening imaging and method of preoperative assessment, and DSA should still serve as a gold standard. Patients had high preference of CTA.Conclusion 3D-CTA has a high sensitivity of detecting intracranial aneurysms, and it is noninvasive, it may be proposed as a first choice modality for screening and preoperative assessment for intracranial aneurysms.