脑血管疾病TOF法磁共振血流成像的初步探讨

Preliminary Experience with Intracranial Vascular Lesions Studied with Three-Dimensional Time of Flight MR Angiography

笔者搜集了７０例诊断明确的脑血管疾病ＭＲＡ资料进行分析。其中２２例经Ｘ线脑血管造影证实。所有患者均进行了三维ＴＯＦ法ＭＲＡ扫描。结果表明，三维ＴＯＦ法能清楚地显示出脑动脉瘤、血管畸形、大动脉的狭窄和阻塞等血管病变，但由于饱和作用的影响，不能显示小动脉分支和静脉血管，并且在血管狭窄的显示方面存在着夸张作用和假象。与Ｘ线血管造影相比，ＭＲＡ虽具有成像迅速、无创伤等优点，但在小血管病变及血管狭窄的显示方面仍有不足。

The authors assessed the clinical application of MR angiography techniques in the e-valuation of cerebrovascular diseases. Twenty patients with the least likelihood of cerebrovascular disease(control group)and 50 patients with highly suspected cerebrovascular disease were imaged with 3D TOF sequence. The results showed that 3D TOF technique was most helpful in evaluation of intracranial aneurysms, vascular dysplasia, and occlusive disease of major vessels,but failed to show any abnormali-ty of slowly flowing blood because of saturation effect and tended to exaggerate the extent of vascular stenosis. In comparison with coriventional contrast angiography,MRA is noninasive,Without radia-tion,and hence is a safe method.It can provide 3D vascular informations in a short examination time.The disadvantages of MRA include less spatial resolution, signal loss from complex flow,problem from patient motion, and inadequate depiction of lesion with slow flow.