MR动态增强时间减影技术对肺癌体循环血供定性及定量评估的价值

The value of MR dynamic time-resolved subtracted imaging in evaluating the blood supply by systemic artery in patients with lung cancer

目的 探讨MR动态增强时间减影技术在肺癌体循环血供定性及相对定量评估中的应用价值。方法 对 5 1例经细胞学或 /和组织学证实的肺癌病例采用FSPGR序列行增强后灌注扫描 ,将强化前与造影剂首过期肺循环不同时相的图像进行数字减影处理。根据时间信号曲线测量肺癌肿块 (M )、正常肺实质(PP)、肺动脉干 (PA)及降主动脉 (DA)的增强起始时间 (ST)、峰值时间 (PT) ,以及肿块与正常肺组织在PA期和DA期信号增强率 (EMP、EMA、EPP、EPA) ,结合PA及DA期减影图像 ,确定肺癌血供来源。结果 5 1例首过期时间减影图像显示 ,肺动脉期 7例癌块为低信号 ,2例为中等信号 ,其余无信号 ;主动脉期 5 1例癌块均为高信号。正常肺组织ST[( 5 .90± 0 .5 1)s]和PT[( 12 .75± 0 .67)s]稍延后于肺动脉的ST[( 4 .19± 0 .43 )s]和PT[( 10 .5 9± 0 .66)s] ,肺癌肿块的ST[( 11.0 3± 0 .80 )s]和PT[( 3 3 .62± 3 .0 6)s]滞后于主动脉ST[( 9.43± 0 .5 9)s]和PT[( 19.81± 4.14 )s]。肺癌肿块的EMA明显高于EMP( 91.47%± 18.83 %vs 15 .3 8%± 11.0 3 % ,P <0 .0 0 1) ,肺实质的EPP明显高于EPA( 2 73 .83 %± 48.60 %vs 14 0 .65 %± 2 4.40 % ,P <0 .0 0 1)。结论 MR动态增强时间减影技术可望成为肺癌体循环血供定性及相对定?

Objective To explore the application value of MR dynamic time resolved subtracted imaging in qualitative and quantitative assessment of blood supply by systemic artery in patients with lung cancer. Methods A prospective study using MR FSPGR pulse sequence dynamic scan after contrast enhancement was undertaken in fifty one patients with lung cancer which were proved by cytology or/and histology. The time resolved subtracted imaging were acquired using the pre and post enhanced images in different phases of pulmonary circulation during the first pass period (FPP) of contrast agent. The time signal curves of FPP at four ROI placed on pulmonary artery (PA), descending aorta (DA), mass (M) and contralateral pulmonary parenchyma (PP), and the ST (start time) and PT (peak time) of those four ROI were measured. The enhancement ratio of the signals of M/PP at PA/DA peak time (E MP , E MA , E PP , E PA ) were calculated. Results According to the time resolved subtracted imaging during PA phase, intensity of the signal was low in 7 cases, medium in 2, but not enhanced in other 42 cases. All the 51 cancer masses were remarkably enhanced during DA phase. During FPP, the ST [(5.90±0.51)s] and PT [(12.75±0.67)s] of PP were slightly later than the ST [(4.19±0.43)s] and PT [(10.59±0.66)s] of PA, while the ST [(11.03±0.80)s] and PT [(33.62±3.06)s] of cancer masses were later than ST [(9.43±0.59)s] and PT [(19.81±4.14)s] of DA. E MA was significantly higher than E MP (91.47%±18.83% vs 15.38%±11.03%, P<0.001), while E PP were remarkably higher than E PA (273.83%±48.60% vs 140.65%±24.40%, P<0.001). Conclusion MR dynamic time resolved subtracted imaging is feasible to be a non invasive technique in qualitative and relatively quantitative assessment of blood supply by systemic artery in patients with lung cancer.