摘要
目的探讨MRDTI在评价胶质瘤病理等级与毗邻纤维束状态之间相关性的价值。方法选择24例经手术及组织病理学证实的胶质瘤患者，术前行常规MRI、DTI。在各向异性分数（FA）图上，ROI设定在瘤周纤维束FA值最低点（FAa）及对侧半球对称区域（FAc），测量出FAa及FAc值，在相同层面ADC图的相同位置，测量出ADC值最低点（ADCa）及对侧半球对标区域ADC（ADCc）值，计算出相对FA值（rFA）和相对ADC值（rADC）。利用纤维束追踪技术重组出肿瘤周围纤维束三维图，根据纤维束三维图对纤维束的状态（推移、浸润或者破坏）进行评价。rFA、rADC及瘤周纤维束的状态与胶质瘤的病理级别之间的关系进行独立样本t检验及趋势χ^2检验。结果24例胶质瘤患者，其中低级别胶质瘤11例，高级别胶质瘤13例。低级别胶质瘤的rFA值为0．65±0．19，rADC值为1．43±0．50，重组的瘤周纤维束追踪图主要呈被推移或者浸润；高级别胶质瘤的rFA值为1．51±0．39，rADC值为1．70±0．27，重组的瘤周纤维束追踪图主要呈被浸润或者被破坏。rFA值在高级、低级别胶质瘤之间差异有统计学意义（t=8．504，P=0．000），而rADC值差异无统计学意义（t=-1．435，P=0．165）；纤维束的状态在高级、低级别胶质瘤之间差异亦有统计学意义（χ^2=5．882，P=0．015）。结论胶质瘤的病理等级影响瘤周纤维束的状态，rFA可作为一个参考指标，有助于鉴别胶质瘤的恶性程度；DTI可清楚显示肿瘤与周围白质纤维的解剖位置关系，并能显示瘤周纤维束的病理状态，指导治疗方案的制定。
Objective To investigate the relationship between the grade of gliomas and the status of adjacent fiber tract with DTI. Methods MRI and DTI were performed in 24 patients with histologically confirmed brain gliomas. Regions of interest were placed in the white matter adjacent to the tumor with the lowest FA（FAa） and in the white matter of the contralateral hemisphere（FAc）. The values of FAa and FAc were measured. In the regions of the same slice, the values of ADCa and ADCc were measured. Relative fractional anisotropy ratios （rFA） and relative apparent diffusion coefficient ratios （rADC） were also calculated. The status of fiber tracts adjacent to the gliomas were characterized as displacement, infiltration or disruption. Fiber tracking using the Fiber Assignment by Continuous Tracking （FACT） method was performed to investigate the integrity of white matter tracts in the surrounding border zone of the gliomas. The correlation of rFA, rADC, the state of adjacent fiber tracts, and the grade of gliomas were analyzed statistically by using independent sample t test and tendency χ^2 test. Results Eleven of the 24 tumors were demonstrated as low grade gliomas （ WHO grade Ⅰ - Ⅱ ） and 13 were high grade gliomas （ WHO grade Ⅲ-Ⅳ）. The average rFA and rADC of the low grade gliomas were 0. 65 ± 0. 19 and 1.43 ± 0. 50 respectively. Most of fiber tracts in the periphery of the low grade gliomas were displaced or infiltrated. Theaverage rFA and rADC of the high grade gliomas were 1.51 ± 0. 39 and 1.70 ± 0. 27 respectively. Most of fiber tracts in the periphery of the high grade gliomas were infiltrated or disrupted. Significant difference was found for rFA （ t = 8. 504, P = 0. 000 ） and but not for rADC （ t = - 1. 435, P = 0. 165 ） between low grade and high grade gliomas. Significant difference existed between the state of fiber tracts adjacent to gliomas and low and high-grade（ χ^2 = 5. 882, P = 0. 015 ）. Conclusions The malignancy of gliomas influences the state of fiber tracts in the vicinity of tumors, rFA can serve as a reference for distinguishment of high-grade and low-grade gliomas. DTI can depict the localization of gliomas and the adjacent fiber tracts. The state of fiber tracts can also be identified by DTI. It is helpful for the therapeutic plan of the tumors.
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2009年第4期343-346,共4页
Chinese Journal of Radiology
基金
安徽省科技攻关基金资助项目（07010302202）
关键词
神经胶质瘤
磁共振成像
弥散
病理学
Glioma
Diffusion magnetic resonance imaging
Pathology
