Pavone P, Catalano C, Di Girolamo M, Albertini Petroni G, Marsili L, Passariello R
Istituto di Radiologia, Università di Roma La Sapienza.
Radiol Med. 1993 Nov;86(5):579-86.
Magnetic Resonance Angiography (MRA) is the latest diagnostic technique for the noninvasive evaluation of cardiovascular conditions. This technique has proved to be especially useful in the study of carotid arteries. All the clinical studies reported to date have been obtained at high or medium field strength; our purpose is to assess the clinical value of MRA in the evaluation of carotid arteries at low field strength. All the exams were performed with an 0.2 T permanent magnet, using the 2D time of flight (TOF) technique, the only one which is currently available on our equipment. Forty-two patients with clinical diagnosis of cerebrovascular insufficiency were examined. In all cases MRA findings were confirmed with digital subtraction angiography (DSA), which was considered the gold standard. The double-blind evaluation of the results showed high agreement of the two techniques in 70 of 84 carotid arteries. A mild tendency to overestimation was observed in 4 normal cases considered as mild stenoses on MRA, in 2 cases with mild stenosis considered as discrete stenoses on MRA and in 1 case of severe stenosis considered as an occlusion on MRA. Underestimation was seen in 1 case of mild stenosis considered as normal on MRA, in 2 cases of discrete stenosis which appeared as mild stenoses on MRA and in 2 cases of occlusion considered as severe stenoses. Our study showed high agreement between MRA and DSA results, which means that high quality exams can be obtained even at low field strength. Further progress can be expected when 3D TOF and phase-contrast techniques will be introduced.
磁共振血管造影（MRA）是用于心血管疾病无创评估的最新诊断技术。该技术已被证明在颈动脉研究中特别有用。迄今为止报道的所有临床研究均在高场或中场强度下进行；我们的目的是评估低场强下MRA在颈动脉评估中的临床价值。所有检查均使用0.2 T永磁体进行，采用二维时间飞跃（TOF）技术，这是目前我们设备上唯一可用的技术。对42例临床诊断为脑血管供血不足的患者进行了检查。在所有病例中，MRA结果均通过数字减影血管造影（DSA）得到证实，DSA被视为金标准。对结果的双盲评估显示，在84条颈动脉中的70条中，两种技术高度一致。在4例正常病例中，MRA将其视为轻度狭窄，存在轻度高估倾向；在2例轻度狭窄病例中，MRA将其视为离散狭窄；在1例严重狭窄病例中，MRA将其视为闭塞。在1例轻度狭窄病例中，MRA将其视为正常，存在低估情况；在2例离散狭窄病例中，MRA将其显示为轻度狭窄；在2例闭塞病例中，MRA将其视为严重狭窄。我们的研究表明MRA和DSA结果高度一致，这意味着即使在低场强下也能获得高质量的检查结果。当引入三维TOF和相位对比技术时，有望取得进一步进展。
