Haque S, Hossain A, Quddus M A, Jahan M U
National Institute of Cancer Research & Hospital, Dhaka.
Bangladesh Med Res Counc Bull. 2011 Dec;37(3):92-6. doi: 10.3329/bmrcb.v37i3.9120.
Magnetic Resonance Imaging (MRI) has been the primary imaging modality and has revolutionized the imaging of brain tumors. MRI can display accurate multi planer imaging without interfering of adjacent structures specially for posterior fossa mass lesion. MRI is the imaging modality of choice for cerebollo-pontine (CP) angle Schwannoma. The study was performed to determine, the diagnostic accuracy of MRI in the evaluation of intracranial extra axial CP angle Schwannoma. MRI scan of brain was done on 42 consecutively selected patients referred for the evaluation of CP Acoustic Schwannoma. The age range from 21-60 years and the mean age was 42.85 (+/- 9.5) years. Highest incidence of cerebollo-pontine angle (CPA) mass were found 42.86% in 41-50 age group of patients. Male and Female ratio was 1.083:1. The most common presenting feature of the patients with CP angle Acoustic Schwannoma were headache 90.48%. Acoustic Schwannoma is T1 hypointense 100%, T2 hyper intense 84.61% and heterogeneously hyper intense 92.30% in FLAIR image. After giving contrast agents, homogeneous enhancement 57.69% and heterogeneous 42.31% cases of Acoustic Schwannoma. Overall 61.54% Acoustic Schwannoma strong contrast enhancement was observed. Dural tail was observed in 26.92% cases. Perilesional edema was observed 38.46% cases. Mass effect was observed in 76.92%. After complete MRI evaluation 61.9% had Acoustic Schwannoma. Histopathologicaly proved cases showed out of all patients Acoustic Schwannoma 59.52%. The overall sensitivity of MRI to diagnose Acoustic Schwannoma were found, Sensitivity- 96%, Specificity- 88.2%, PPV-92.31%, NPV-93.75% and Acceuracy 92.86%. Test is significant with p < 0.0001 level. It is conceivable that MRI is a highly accurate, sensitive and Gadolinium enhanced MRI is more sensitive in detection of acoustic Schwannoma. MR imaging is the study of choice for the examination of the patient of cerebellopontine angle Schwannoma because of its high sensitivity specially after use of contrast material.
磁共振成像（MRI）一直是主要的成像方式，并且彻底改变了脑肿瘤的成像技术。MRI能够显示准确的多平面成像，而不会干扰相邻结构，对于后颅窝肿块病变尤为适用。MRI是桥小脑（CP）角神经鞘瘤的首选成像方式。本研究旨在确定MRI在评估颅内轴外CP角神经鞘瘤时的诊断准确性。对42例连续入选的因评估CP听神经鞘瘤而转诊的患者进行了脑部MRI扫描。年龄范围为21至60岁，平均年龄为42.85（±9.5）岁。在41至50岁年龄组的患者中发现桥小脑角（CPA）肿块的发生率最高，为42.86%。男女比例为1.083:1。CP角听神经鞘瘤患者最常见的临床表现是头痛，占90.48%。听神经鞘瘤在T1加权像上呈低信号的比例为100%，在T2加权像上呈高信号的比例为84.61%，在液体衰减反转恢复（FLAIR）图像上呈不均匀高信号的比例为92.30%。给予造影剂后，听神经鞘瘤均匀强化的病例占57.69%，不均匀强化的病例占42.31%。总体而言，观察到6️1.54%的听神经鞘瘤有明显强化。26.92%的病例观察到硬膜尾征。38.46%的病例观察到瘤周水肿。76.92%的病例观察到占位效应。经过完整的MRI评估，61.9%的患者患有听神经鞘瘤。组织病理学证实的病例在所有听神经鞘瘤患者中占59.52%。发现MRI诊断听神经鞘瘤的总体敏感性为：敏感性-96%，特异性-88.2%，阳性预测值-92.31%，阴性预测值-93.75%，准确性-92.86%。检验在p<0.0001水平上具有显著性。可以想象，MRI是一种高度准确、敏感的检查方法，而钆增强MRI在检测听神经鞘瘤方面更敏感。由于其高敏感性，尤其是在使用造影剂后，MR成像成为检查桥小脑角神经鞘瘤患者的首选检查方法。
