CT灌注成像对鼻咽癌的诊断、放疗及预后评估的价值

目的探讨CT灌注成像在评价鼻咽癌的诊断、放疗及预后评估等方面的应用价值。方法54例经病理学证实的鼻咽癌在放疗前行多层螺旋CT灌注扫描,其中18例在放疗50 Gy时再次行灌注扫描,将放疗前、后的灌注参数进行配对设计t检验。随访34例,随访时间21~61个月,中位时间52个月,以是否局部复发或/和转移为标准进行分组,并对各组病例放疗前肿瘤灌注参数进行独立样本t检验。所作统计学处理均采用SPSS 11.5软件。结果54例放疗前组织血流量、血容量、表面通透性、平均通过时间、强化峰值分别为(341.2±137.5)ml.100 g-1.min-1、(10.4±10.5)ml/100g、(65.5±17.3)ml.100g-1.min-1、(4.3±5.8)s、(55.9±14.7)Hu,放疗组灌注参数分别为(351.4±191.0)ml.100 g-1.min-1、(8.8±5.1)ml/100 g、(65.0±20.5)ml.100 g-1.min-1、(3.5±2.0)s、(46.6±13.5)Hu。放疗前与放疗组间灌注参数进行配对设计t检验,肿瘤强化峰值有显著性差异(P=0.006),其余各参数之间无统计学差异。复发/转移组与其他各组间放疗前灌注参数无统计学差异。结论灌注参数可以定量反映鼻咽癌的微循环特征。放疗前和放疗中的强化峰值有显著差异,表现为明显减低。灌注参数难以预测肿瘤放疗后复发及

CT perfusion in diagnosis of nasopharyngeal carcinoma and prognosis prediction after radiotherapy

Objective To assess the value of CT in diagnosis of nasopharyngeal carcinoma (NPC) and prognosis prediction. Methods Fifty-four cases of NPC proved by nasopharyngoscopy biopsy underwent multislice CT perfusion imaging before radiotherapy, of which 18 cases had second perfusion CT scan when radiation doses were escalated to 50 Gy. Paired-samples t-test was used to analyse the perfusion parameters of pre-radiation and post-radiation. Thirty-four cases were followed up for 21 to 61 months, with median of 52 months. The cases were divided into groups according to whether they had local recurrence or/and metastasis. The parameters of those groups before radiotherapy were assessed with independent-sample t-test. All the data were statistically processed with SPSS 11.5 software. Results Before radiotherapy, the tissue blood flow, blood volume, surface permeability, mean transit time, peak height of 54 cases were (341.2±137.5) ml·100 g^-1·min^-1, (10.4±10.5) ml/100 g, (65.5±17.3) ml·100g^-1·min^-1, (4.3±5.8) s and (55.9±14.7) Hu respectively. After radiation of 50 Gy, these parameters were (351.4±191.0) ml^-1·100g^-1·min^-1, (8.8±5.1) ml/100 g, (65.0±20.5) ml·100g^-1·min^-1, (3.5±2.0) s and (46.6±13.5) Hu respectively. On paired-samples t-test, there was significant difference in peak height between pre- and post-radiation data (P=0.006), while there was no statistic significant difference in other parameters. Between the group with recurrence or/and metastasis and other groups, there was no statistic difference in parameters of perfusion before radiotherapy. Conclusion Perfusion CT can reflect the microcirculation features of NPC quantitatively. After radiation of 50 Gy, peak height decreased significantly compared with that of pre-radiation. It is difficult to predict recurrence or metastasis of NPC after radiotherapy with the perfusion parameters.