磁共振肺动脉造影在肺动脉栓塞诊断中的应用价值评估

The clinical value of MRI pulmonary artery angiography in the diagnosis of pulmonary artery embolism

目的探讨MR T2-trufi序列及增强磁共振肺动脉造影(magnetic resonance pulmonary angiography,MRPA)在肺动脉栓塞诊断中的应用价值。方法选择成年健康中国大耳白兔30只,制备家兔肺动脉栓塞模型,分别进行CT肺动脉造影(computed tomography pulmonary angiography,CTPA)、MRPA及MR T2-trufi序列扫描,将肺动脉血管按照血管直径分级,并将各级肺动脉血管直径,血管边缘、密度/信号等基本数据以及肺动脉血栓检出结果进行比较。结果 13种检测方法的Ⅰ级血管直径差异无统计学意义(P>0.05);T2-trufi序列检出Ⅱ级血管直径大于CTPA和MRPA(P<0.05);Ⅲ级和Ⅳ级血管直径MRPA较CTPA和T2-trufi序列更大(P<0.05)。2Ⅰ级血管清晰度比较,T2-trufi和MRPA均不如CTPA,差异有统计学意义(P<0.05);Ⅱ级血管清晰度比较,T2-trufi序列和MRPA均不如CTPA,MRPA最差(P<0.05);Ⅲ级血管清晰度比较,T2-trufi序列和MRPA低于CTPA(P<0.05),T2-trufi序列与MRPA差异无统计学意义(P>0.05);Ⅳ级血管清晰度比较,CTPA高于T2-trufi序列和MRPA(P<0.05),T2-trufi序列与MRPA之间差异无统计学意义(P>0.05)。3Ⅱ级肺动脉血栓检出率比较,CTPA与T2-trufi序列差异有统计学意义(P<0.05);Ⅲ级肺动脉血栓检出率比较,CTPA高于T2-trufi序列、MRPA,差异有统计学意义(P<0.05)。结论 MR T2-trufi序列及MRPA在肺动脉栓塞诊断中具有强大的优势,但磁共振扫描时间和信噪比仍然是血管造影不可回避的弱点,故磁共振扫描目前不可取代CTPA检查,但可作为CTPA检查的有益补充。

Objective To discuss the value of MR T2-trufi bright blood sequence and contrastenhanced magnetic resonance pulmonary angiography（ MRPA） in the diagnosis of pulmonary artery embolism. Methods Thirty healthy adult Chinese white rabbit were chosen as experimental animal and were examined using computer tomography pulmonary angiography（ CTPA） 、MRPA and MR T2-trufi bright blood sequence separately. Their pulmonary arteries were graded by vessel diameter. The basic values such as vessel diameter,vessel edge and density in each grade of pulmonary artery were compared with each other and with the results of pulmonary artery embolism. Results 1In the display of vessel diameters,MRPA and CTPA,MR T2-trufi bright blood sequence had no significant difference in thedisplay of grade Ⅰ pulmonary artery（ P〈0. 05）; MR T2-trufi bright blood sequence detected a larger diameter than MRPA and CTPA in gradeⅡpulmonary artery（ P〈0. 05）; MRPA had a larger diameter than CTPA and MR T2-trufi bright blood sequence in Ⅲ and Ⅳpulmonary artery（ P〈0. 05）.（2）In the display of vessel clarity,CTPA was superior than MR T2-trufi bright blood sequence and MRPA in gradeⅠpulmonary artery（P〈0. 05）; CTPA was superior than MR T2-trufi bright blood sequence and MRPA in gradeⅡpulmonary artery,and MRPA was the worst（ P〈0. 05）; In grade Ⅲ and Ⅳpulmonary artery,CTPA was superior than MR T2-trufi bright blood sequence（ P〈0. 05）,and MRPA had no significant difference with MR T2-trufi bright blood sequence（ P〈0. 05）.（3）In the detection of pulmonary emboli,CTPA and MR T2-trufi bright blood sequence had significant difference in gradeⅡpulmonary artery（ P〈0. 05）; CTPA and MR T2-trufi bright blood sequence,MRPA had significant difference in grade Ⅲpulmonary artery（ P〈0. 05）. Conclusion MR T2-trufi bright blood sequence and MRPA pulmonary artery angiography had obvious advantage in the diagnosis of pulmonary artery embolism, but the examination time and signal-noise ratio are inevitable pitfalls. MR can not replace CTPA examination up till now,but can be an beneficial supplement.