ASL在胶质瘤分级中的初步应用

目的评价动脉血质子自旋标记(ASL)技术在胶质瘤灌注中的临床应用价值.方法健康志愿者7名,颅内占位患者42例,经手术及病理证实其中胶质瘤35例,高级胶质瘤18例,低级17例.使用3.0 T MR成像系统对每人行常规扫描外,加扫可一次采集多层的第二版本Q2TIPS的ASL序列.观测所得相对脑血流量(CBF)图,数据使用SPSS 11.0软件包处理分析.结果在健康志愿者中ASL可清楚显示脑灰、白质及深部核团的血流分布不同.在患者中ASL显示了高级胶质瘤的高血流量和低级别的低血流灌注,并且可显示同一肿瘤不均匀的血流分布.相对肿瘤血流量(TBF)在高低级胶质瘤间有显著性差异(P＜0.00001).结论ASL可用于脑肿瘤微血管灌注的评估,有助于区分低级和高级胶质瘤.

Arterial spin labeling in the grading of gliomas: preliminary application

Objective To implement an arterial spin labeling (ASL) technique that is feasible in routine examinations and to evaluate the clinical application of the method for imaging blood flow in brain gliomas. Methods Seven volunteers and forty-two patients with intracranial space-occupying lesions were examined at a clinical 3.0-T imaging unit (Magnetom Trio;Siemens). In the patients with brain tumors, thirty-five cases with histologically proven gliomas were included in the study, which were respectively 18 high-grade gliomas and 17 low-grade tumors. A second version of quantitative imaging of perfusion by using a single subtraction with addition of thin-section periodic saturation after inversion and a time delay (Q2TIPS) technique of pulsed ASL in the multisection mode was implemented, and MR routine examinations were also included. In regions of interest, maps of relative cerebral blood flow (CBF) were computed and analyzed. Statistical analysis was performed by using SPSS 11.0. Results In the volunteers, different cerebral blood flows of gray and white matter determined with ASL were clearly observed. In the patients, ASL technique yielded the higher perfusion values in imaging of high-grade gliomas and the lower values in imaging of low-grade tumors. ASL showed heterogeneous vascularization of some tumors. Statistical analysis demonstrated high-and low-grade gliomas differed significantly (P<0.00001) in terms of the ratios of relative tumor blood flow (TBF) to mean CBF. Conclusion The ASL is a suitable method for assessment of tumorous microvascular perfusion and allows distinction between high- and low-grade gliomas.