摘要
目的探讨弥散张量成像（diffusion tensor imaging，DTI）对颅内环形强化病变的诊断价值。方法53例颅内单发环形强化病例术前行DTI扫描，分别测量病变坏死区、灶周水肿区及对侧正常脑实质的平均弥散系数（MD）值及各向异性分数（FA）值。并通过弥散张量纤维束成像（diffusion tensor tracking，DTT）观察病灶与白质纤维束的关系。结果脑脓肿坏死区的MD值为（0．60±0．13）×10^-3mm^2／s，FA值为0．18±0．03，高级别星形细胞瘤MD值为（2．76±0．26）×10^-3mm^2／s，FA值为0．07±0．02，脑转移瘤MD为（2．82±0．29）×10^-3mm^2/s，FA值为0．06±0．02，前者与后两者间差异有统计学意义（P〈0．01）。高级别星形细胞瘤水肿区的FA值（0．23±0．06）与脑转移瘤（0．17±0．06）和脑脓肿（0．15±0．03）两者水肿区FA值差异有统计学意义（P〈0．01）。DTT可以较准确地反映病灶与白质纤维柬的关系，为手术治疗及评估预后提供依据。结论坏死区MD值及FA值有助于脑脓肿与环形强化脑肿瘤的鉴别；水肿区FA值有助于脑星形细胞瘤与转移瘤、脑脓肿的鉴别；DTT能够为优化手术方案及评估预后提供一定帮助。
Objective To determine differential diagnostic value and clinical significance of diffusion tensor imaging （DTI） in high-grade astroeytomas, solitary metastasis and abscesses. Method 53 patients with intracranial solitary lesions which showed ring enhancement sign on contrast-enhanced T1- weighted images were enrolled in this study. Brain tissues were examined pathologically from 50 patients to confirm the intracranial occupational diseases. Three patients have been diagnosed with primary cancer plus brain solitary metastasis. DTI measurements were obtained from regions of interest （ROI） placed on central cavity, peri-edema and cerebral parenchyma of the normal side. Fiber tractography was reconstructed that diaplay the encountered patterns of tumor-related alteration to cerebral white matter. Results On DTI, the cavity of high-grade astrocytoma and metastases displayed as hypo-intense signal; most of the absecess cavities displayed high signal intensity except for one with an isodensity cavity. MD values and FA values aid the differentiation between tumors and abscesses. The abscess cavities showed restricted diffusion and anisotropy （ MD = 0. 60± 0. 13 ×10^-3mm^2/s, FA = 0. 18 ±0. 03 ）, whereas the central portion of high- grade astrocytoma （MD =2. 76 ±0. 26×10^-3mm^2/s, FA =0. 07 ±0. 02） and solitary metastases （2. 82 ± 0. 29 ×10^-3mm^2/s, FA = 0. 06 ～ 0. 02） showed unrestricted diffusion and isotropy. Abscesses could be differentiated by MD values and FA values in their cavities from brain tumors（ P 〈0. 01 ）. The peri-edemas were all depicted as hyperintense or iso-intense signals on DTI. The difference of FA values in the peri- edemas between high-grade astrocytomas and others was statistically significant （ P 〈 0. 01 ）. Furthermore, Fiber tractography and FA map could give a quick and intuitive overview of the displaced course of white matter tracts in three-dimensional space. Conclusions Our results suggest the potential role of the cavity MD values and cavity FA v
出处
《中华神经外科杂志》
CSCD
北大核心
2009年第3期255-258,共4页
Chinese Journal of Neurosurgery
关键词
成像
脑肿瘤
脑脓肿
Magnetic resonance imaging
Brain neoplasms
Brain abscess
