Takahashi M
Department of Radiology Kumamoto University School of Medicine.
Rinsho Shinkeigaku. 1995 Dec;35(12):1567-8.
With the recent development of MR techniques, it has become possible to obtain angiographic images (MRA) of relatively good quality with use of MR. The major indications of MRA have been to elucidate the MR findings on spin echo images when vascular lesions are suspected and to use MRA for conventional angiography when the latter is contra-indicated or additional information is needed. Follow-up studies of vascular diseases can be easily performed with MRA. The sensitivity of this technique for cerebral aneurysms is 73.6%, whereas specificity is 76.2%. The sensitivity and specificity for cerebrovascular diseases are 88.7% and 97.4% for stenoses of more than 50.0%. Because of rather limited diagnostic accuracy, this technique cannot be applied freely for screening of cerebral diseases, especially in mass survey for unruptured cerebral aneurysms. There have been many new techniques proposed for improvement of spatial resolution of MRA, including magnitisation transfer contrast (MTC), tilted optimized non-satulation excitation (TONE) and high resolution images. With full development of these new techniques, MRA will be used more freely in the diagnosis of vascular diseases.
随着磁共振（MR）技术的最新发展，利用MR获得质量相对较好的血管造影图像（MRA）已成为可能。MRA的主要适应证包括：当怀疑有血管病变时，阐明自旋回波图像上的MR表现；当传统血管造影禁忌或需要额外信息时，将MRA用于传统血管造影。利用MRA可以轻松地对血管疾病进行随访研究。该技术对脑动脉瘤的敏感性为73.6%，特异性为76.2%。对于超过50.0%的狭窄，脑血管疾病的敏感性和特异性分别为88.7%和97.4%。由于诊断准确性相当有限，该技术不能随意用于脑部疾病的筛查，尤其是在未破裂脑动脉瘤的大规模筛查中。为提高MRA的空间分辨率，已经提出了许多新技术，包括磁化传递对比（MTC）、倾斜优化非饱和激发（TONE）和高分辨率图像。随着这些新技术的充分发展，MRA将在血管疾病的诊断中得到更广泛的应用。
