MRI动态增强技术对鼻咽癌放疗后局部纤维化与复发的诊断研究

目的本研究对鼻咽癌放疗后复查的患者行MRI动态增强检查,旨在了解肿瘤局部纤维化与复发的动态增强特点,探讨动态增强MRI技术在鼻咽癌放疗后局部复发与纤维化的鉴别诊断中的价值。方法将我院从2011年3月到2013年6月的67例经放射治疗后的鼻咽癌患者分为2组：放疗后局部纤维化组38例及复发组29例,男45例,女22例;年龄22-72岁,平均42±1.5岁。行MRI动态增强后,行常规增强T1WI扫描。测量他们注射钆喷酸葡胺（Gd-DTPA）后0s至3min期间病变同一区域各时相的T1WI信号强度。应用分析软件测量ROI的信号强度,获取两组病例动态增强的时间-信号强度曲线（TIC）并对其达峰时间（PT）、曲线最大斜率（Slopemax）、曲线下面积（AUC）三个参数进行统计学分析。结果放疗后鼻咽癌局部纤维化组达峰时间（PT）低于复发组的达峰时间,经过样本均数方差分析,纤维化组与复发组比较,差别无统计学意义（p〉0.05）。放疗后鼻咽癌患者纤维化组曲线最大斜率（Slopemax）明显低于复发组的最大斜率值（Slopemax）,差别具有统计学意义（p〈0.05）。放疗后鼻咽癌患者纤维化组曲线下面积（AUC）低于复发组的曲线下面积（AUC）,差别无统计学意义（p〉0.05）。结论 MRI动态增强技术对鼻咽癌放疗后局部复发与纤维化的鉴别具有重要的临床意义。

Diagnosis Research of Dynamic Enhanced MRI in Nasopharyngeal Carcinoma Radiofibrosis and Recurrent

Objective This study was designed to investigate the characteristics of nasopharyngeal carcinoma recurrence （RNPC） and fibrosis （RF） on dynamic enhanced magnetic resonance imaging （DMRI） technology, calculated the dynamic change of T1WI signal intensity to value of RNPC and RF based on DMRI diagnosis. Methods A total cases of 67 NPC patients of our hospital from March 2011 to June 2013 were divided into 2 groups： 38 in RF group and 29 in RNPC group, male 45 cases, female 22 cases; Age 22-72ys, average 42±1.5ys. After conventional plain MRI scan of nasopharynx, DMRI and conventional contrast enhanced T1-weighted imaging （T1WI） were performed. A circle area in tumoral parenchyma was selected as region of interest （ROI） , the T1WI signal of ROI was measured during the period from 0s to 3 mins after injection of Gb-DTPA, and the dynamic time-signal intensity curves （TIC） of the two types of turmor were obtained and compared. Maximal contrast enhancement ratio （MCER）, Peak time to MCER （PT）, The area under the concentration time curve （AUC） were measured. Results The PT of RF group is lower than those of RNPC group, after sample mean variance analysis, no significant differences of PT were found between the two groups （p〉0.05）. The Slopemax of RF group is significantly lower than those of RNPC group, with statistically significant difference （p〈0.05）. The AUC of RF group is lower than those of RNPC group, with no significant differences （p〉0.05）. Conclusion DMRI may provide important clinical information for differential diagnosis of RNPC and RF.