pc-ASL技术在桥小脑角区肿瘤术后复发评估

The diagnostic value of PCASL MRI technique in evaluating post-operative recurrence of cerebellopontine angle tumor

目的:探讨3DFSE的pc-ASL技术对桥小脑角区肿瘤术后复发的诊断价值。方法:选取21例桥小脑角区占位性病变术后患者,行常规平扫及增强序列,在增强前扫描pc-ASL序列。将pc-ASL功能图像与增强后Ax 3D T1WI融合,测量异常强化区域及对侧正常脑组织的CBF值,评价是否存在肿瘤复发。结果:全部21例手术区出现异常强化区患者,13例为复发。17例患者行DSC-PWI失败,图像无法满足诊断需求。全部21例pc-ASL检查成功。肿瘤复发区域的CBF值为(64.2±3.03)mL/100g/min,对侧正常脑实质的CBF值为(52.5±1.89)mL/100g/min。肿瘤复发区域的CBF值明显高于对照侧脑组织,两者之间差异有统计学意义(t=12.498,P<0.05)。结论:基于3DFSE的pc-ASL序列安全无创,无需注射对比剂,磁敏感效应影响小,可以用于评估桥小脑角区肿瘤有无术后复发。

Objective：The purpose of this study was to assess the diagnostic value of 3DFSE pseudo-continuous arterial spin labeling（pCASL）technique in evaluating post-operative recurrence of cerebellopontine angle tumor.Methods：21post-operative patients with cerebellopontine angle tumor underwent pre-and post-contrast MRI scans.Perfusion-weighted MR imaging（PWI）with pCASL technique was performed before contrast injection.The CBF maps generated from pCASL were fused with post-contrast 3D T1 WI.The CBF values of abnormal enhanced area and contralateral normal brain tissue were measured and statistically analyzed to assess whether there was a recurrence of the neoplasm.Results：The neoplasm recurrence was found in 13/21 cases.DSC-PWI failed to generate functional maps in 17/21 cases due to the susceptibility artifact;however,all 21 cases successfully underwent pCASL scan using 3D-FSE sequence.The mean CBF values were（64.2±3.03）mL/100g/min for the recurrent neoplasm and（52.5±1.89）mL/100g/min for the contralateral normal brain tissue,respectively.There was statistically significant difference（t=12.498,P〈0.05）.Conclusion：With several advantages,including non-invasive,non-contrast and free of susceptibility effect,3DpCASL technique can be used to assess the tumor recurrence in cerebellopontine angle.