下肢动脉电子束CT血管造影及三维成像初探

Electron beam computed tomographic angiography and three dimensional reconstruction of lower extremity arteries

目的:探讨电子束CT(EBCT)血管造影对下肢动脉病变的扫描和三维成像方法以及临床应用价值。方法:18例可疑下肢动脉病变的患者行电子束CT连续容积增强扫描(CVS)和三维重建成像。三维重建方法主要应用最大密度投影法(MIP)、曲面重建法(CPR)和容积再现法(VR)。结果:动脉硬化闭塞症12例,正常5例,其中1例为正常胫后动脉受肿瘤压迫而致狭窄症状。外伤致假性动脉瘤1例,MIP、CPR及VR法均可显示髂外动脉至踝以上下肢动脉主干,MIP与CPR成像最清晰,VR成像血管边缘欠清晰,可夸大狭窄的程度。结论:电子束CT是快速、无创的下肢动脉疾病检查方法,有较好的诊断准确性和应用前景。限度是空间分辨率低,对三级以下分支血管显示欠佳和扫描长度受限制。

Objective: To investigate the clinical values, scanning skills and three dimensional reconstruction methods of electron beam computed tomographyEBCT in the diagnosis of arterial disease of lower extremity. Methods: Eighteen patients who were suspected of having arterial disease of lower extremities underwent continuous volume scanning of EBCT and three dimensional reconstruction with maximum intensity projectionMIP, curved planar reformatCPR and volume renderingVR. Results: Twelve of the 18 patients had lower limb atherosclerosis, 5 cases had normal lower limbs arteries, while in 1 case of the normal posterior tibial artery was compressed by a lipoma. One case had traumatic pseudoaneurysm of the left femoral artery. Conclusion: EBCT is a high speed and noninvasive examination for arterial disease of lower limbs with good diagnostic accuracy and application values. The limitation of EBCT is that the spatial resolution of the 3rd 4th grade branches of the lower extremity artery is low, and also the scanning length of the artery is limited.