Tang Y M, Ngai S, Stuckey S
Department of Radiology, Princess Alexandra Hospital, Brisbane, Qld, Australia.
AJNR Am J Neuroradiol. 2006 Mar;27(3):609-11.
The purpose of this study is to investigate the diagnostic utility of fluid-attenuated inversion recovery (FLAIR) in differentiating between glioma and metastasis by assessing for nonenhancing adjacent cortical signal intensity abnormality in patients who present with a solitary enhancing cerebral lesion.
After approval from the institutional ethics committee was obtained, the MR imaging studies of 70 patients with a solitary enhancing lesion, without previous surgery or treatment, were reviewed. The axial FLAIR studies were initially reviewed for cortical involvement. If cortex involvement was detected, comparison with the axial T1, with and without gadolinium enhancement, was made to determine whether the cortex involvement was in an area without enhancement. If this was the case, the study was considered positive for glioma. Statistical analysis consisted of binary logistic regression and a 2 x 2 contingency table.
Involvement of the adjacent cortex with FLAIR signal intensity abnormality but without enhancement was seen in 19 of 70 patients; 16 were gliomas and 3 were solitary metastasis. The sensitivity and specificity of this finding were 44% and 91%, respectively. The positive predictive value for glioma was 84%.
FLAIR, when interpreted in concert with pre- and postgadolinium T1-weighted images, may be useful in differentiating glioma from metastasis when a solitary enhancing cerebral lesion is present. The presence of nonenhancing adjacent cortical involvement in a solitary enhancing lesion is a frequent and relatively specific sign.
本研究旨在通过评估孤立性强化脑病灶患者非强化的相邻皮质信号强度异常，探讨液体衰减反转恢复序列（FLAIR）在鉴别胶质瘤与转移瘤中的诊断价值。
在获得机构伦理委员会批准后，回顾性分析70例未经手术或治疗的孤立性强化病灶患者的磁共振成像（MR）研究资料。首先对轴位FLAIR图像进行皮质受累情况评估。若检测到皮质受累，则与轴位T1加权像（有无钆剂增强）进行对比，以确定皮质受累区域是否无强化。若存在这种情况，则该研究被视为胶质瘤阳性。统计分析包括二元逻辑回归和2×2列联表分析。
70例患者中有19例出现相邻皮质FLAIR信号强度异常但无强化；其中16例为胶质瘤，3例为孤立性转移瘤。这一发现的敏感性和特异性分别为44%和91%。胶质瘤的阳性预测值为84%。
当存在孤立性强化脑病灶时，FLAIR序列与钆剂增强前后的T1加权像联合解读，可能有助于鉴别胶质瘤与转移瘤。孤立性强化病灶中出现非强化的相邻皮质受累是一个常见且相对特异的征象。
