目的 探讨64层CT灌注成像(CTPI)早期诊断放射性肺损伤(RILI)的临床价值。方法48例接受术后放疗的上段食管癌患者(照射总剂量均为60Gy),放疗前及放疗1/2总剂量时间点(30Gy)行CTPI检查,同期检测外周血中肿瘤坏死因子(TNF-a)、转化生长因子(TGF-β),分析发生RILI(A组)与未发生RILI(B组)患者的血清细胞因子、常规CT表现及CTPI灌注值[相对血流量(rrBF)、相对血容量(rrBV)、相对毛细血管通透性(rrPS)]的变化,采用随机区组设计t检验比较两组间血清细胞因子、CTPI灌注值的差异,采用x2检验比较常规cT与CTPI对RILI检出的差异。结果48例患者中,18例发生RILI(A组)。A组放疗前外周血TNF-a和TGF.B1分别为(36.1±15.0)ng/L、(17.54-9.8)μg/L,放疗后分别为(30.4±14.9).g/L、(14.3±7.6)μg/L,放疗前后的差异无统计学意义(t值分别为1.14、1.10,P值分别为0.264、0.279)。放疗1/2总剂量时,A、B两组的外周血TNF—a分别为(30.4±14.9)、(28.9±14.7).g/L,TCF—B,分别为(14.3±7.6)、(14.4±6.0)μg/L,两组间差异无统计学意义(t值分别为0.33、1.23,P值分别为0.746、0.227);但A组常规CT图像上有2例出现阳性征象。受照射肺组织rrBF、rrBV、rrPS照射前,A组分别为1.01±0.13、1.01±0.07、1.03±0.15,B组分别为1.01±0.09、1.00±0.12、1.01±0.17;照射后,A组分别为1.32±0.19、1.30±0.20、1.38±0.20,B组分别为1.20±0.14、1.21±0.09、1.06±0.16。A组受照射肺组织rrBF、rrBV、rrPS均较照射前显著增高,差异有统计学意义(t值分别为5.67、5.97、6.11,P值均为0.000);B组的rrBF、rrBV较照射前有增高,差异有统计学意义(t值分别为6.52、7.84,P值均为0.000),rrPS无明显变化,差异无统计学意义(t=1
Objective To explore the value of 64-slice CT perfusion imaging(CTPI) in the early diagnosis of radiation-induced lung injury (RILI). Methods Forty-eight patients with upper esophageal cancer resection underwent CTPI before and after radiotherapy, and the TNF-a and TGF-β1 were measured from patient's peripheral blood. Serum cytokine, conventional CT appearances and CTPI parameters (rrBF, rrBV, rrPS) in patients with RILI( Group A) and non-RILI (Group B) were compared and analyzed. A randomized block design t-test was used for comparison of serum cytokines and perfusion values between the two groups. The Chi-square ( X2 ) test was used for comparison of detection rate between conventional CT and CTPI. Results RILl occurred in 18 of 48 cases (18/48, Group A). In Group A, TNF-a and TGF-β1 pre- and pos-radiation were (36.1±15.0),(30.4 ±14.9) ng/L and (17.5 ±9.8), (14.3 ±7.6)μg/L, respectively, and there were no statistically significant differences (t = 1.14, 1.10, P =0. 264, 0. 279). At half-dose time point of radiation, there were no significant differences for TNF-a and TGF-β pre- and pos- radiation [(30.4±14.9),(28.9±14.7) ng/L and (14.3±7.6), (14.4±6.0) μg/L, respectively] between Group A and B ( t = 0. 33, 1.23 ; P = 0. 746, 0. 227). The rrBF, rrBV and rrPS of post-radiation from Group A were significantly higher than those of pre-radiation ( t = 5.67,5.97, 6. 11, P = 0. 000, 0. 000,0. 000) , the rrBF and rrBV of post-irradiation from Group B were significantly higher than those of pre-irradiation (t =6. 52, 7. 84, P =0. 000, 0. 000). There was no significant difference for rrPS in Group B pre- and post-radiation (t = 1.36,P =0. 178). There were significant differences for all perfusion values detected from radiation lung fields between Group A and B (t = 2. 32, 2. 18, 6. 04, P = 0. 025, 0. 034, 0. 000). Taking rrPS = 1.28 as a threshold value on ROC, the sensitivity and specificity of CTPI for diagnosis of RILl w