扩散张量成像在颅内良恶性肿瘤诊断中的价值

目的分析扩散张量成像（DTI）在颅内肿瘤定性诊断中的价值。方法搜集经手术病理证实的颅内良恶性肿瘤患者31例，其中良性肿瘤17例，恶性肿癯14例。31例患者均行常规MRI和DTI检查。结果在颅内肿瘤常见的MRI征象中，肿瘤内出血、不均匀强化及中重度瘤周水肿提示恶性肿瘤，而包膜、颅骨改变则提示良性肿瘤可能。良性肿瘤实质区DCavg值较恶性肿瘤高（P〈0．05），瘤周水肿区FA值较恶性肿瘤高（P〈0．01），良性肿瘤实质区FA值及瘤周水肿区DCavg值与恶性肿瘤相比差异均无统计学意义（均P〉005）。良性肿瘤瘤周水肿区白质纤维束以受压移位为主，而恶性肿瘤则有较多的瘤周水肿区白质纤维束破坏，两组之间瘤周水肿区白质纤维束改变的差异有统计学意义（P〈0，01）。结论DTI肿瘤实质区DCavg值、瘤周水肿区FA值及白质纤维束改变，对颅内良恶性肿瘤的鉴别具有重要的价值。

Differential diagnosis of intracranial benign and malignant tumors with diffusion tensor imaging

Objective To investigate the value of diffusion tensor imaging （DTI） in differential diagnosis of intracranial be- nign and malignant tumors. Methods Thirty-one patients with intracranial tumors, including 17 cases of benign tumor and 14 cases of malignant tumors were confirmed pathologically; all patients underwent conventional plain and contrast-enhanced MRI and DTI scans. Results Among common MRI signs, hemorrhage, heterogeneous enhancement and moderate-severe edema may suggest the malignant tumors, while encapsulation and bone changes may suggest benign lesions. DCavg value of solid region of intracranial benign tumors was higher than that of malignant lesions （P 〈 0.05）. FA value of edematous region surrounding benign tumors was higher than that of malignant lesions （P 〈 0.01）. There was no significant difference in FA value of solid region and DCavg value of edematous region between benign and malignant tumors （P 〉 0.05）. Compression and shifting of white mat- ter fiber was predominated in benign tumor, while destruction of white matter fiber was common in malignant tumors. There was significant difference in shape changes of white matter fiber between benign and malignant tumors （P 〈0.01）. Conclusion The DCavg value of solid region of tumors, FA value of edematous region surrounding tumors and shape changes of white matter fiber in diffusion tensor imaging are of value in differential diagnosis of intracranial benign and malignant tumors.