少见部位血管瘤型脑膜瘤的MRI表现及误诊分析

摘要

Objective: To analyze MRI characteristics of intracranial angiomatous meningioma at uncommon sites (IAMAUS) and further improve the diagnostic accuracy of IAMAUS. Methods: A retrospective analysis of MRI examina tions was performed in 9 patients (11 lesions) with IAMAUS (non convex site of cerebrun). All the 11 lesions were proved by pathology. Results: In the 9 cases with IAMAUS,tumors were located in gyrus hippocampi (n=l) ,temporal lobe (n =rnregion (n= 1) and tentorium cerebelli (n= 2) , respectively. The tumor volume ranged from 1. 5cm × 1. 5cm × 2. 5cm to 6cmX6cmX7cm. IAMAUS were round or oval (n = 8) ,lobulated (n = 2) and gourd shaped (n=l). On T1WI,IAMAUSs exhibited mild hypo intensity (n=5) ,iso intensity (n=4) and hyper intensity (n = 2). On T2WI,IAMAUS exhibited mild hyper intensity (n=7),iso intensity (n=4). On contrast enhanced MRI,IAMAUSs exhibited marked homogeneous en hancement (n=7) ,marked heterogeneous enhancement (n=3) ,and no contrast enhancement (n=1) , respectively. Conclu~ sion:MRI can provide valuable diagnostic information for differentiating his to pathological subtypes of meningiomas in terms of associated factors such as IAMAUS is more hypervascular than other subtypes of meningiomas on MRI.%目的:分析少见部位血管瘤型脑膜瘤的MRI征象,提高对该病的诊断及鉴别诊断水平.方法:回顾性分析9例(共11个病灶)经手术和病理证实的非大脑凸面的少见部位血管瘤型脑膜瘤的MRI表现.结果:9例位于非大脑凸面的血管瘤型脑膜瘤,分别位于颞叶深部近海马处、蝶寞内及岩尖、枕骨大孔处、窦汇各1例,位于桥小脑角,小脑幕各2例,同时位于鞍上及鞍内者1例;肿瘤体积1.5 cm×1.5 cm×2.5 cm～6 cm×6 cm×7 cm;圆形或类圆形8个,分叶状2个,葫芦形1个;病灶T1WI呈低信号5个,呈等信号4个,呈略高信号2个;T2WI呈高信号7个,呈等信号4个;病灶强化明显且均匀7个,不均匀强化4个.结论:血管瘤型脑膜瘤具有较其他类型脑膜瘤更富血供的影像学特征.MRI可为血管瘤型脑膜瘤的鉴别诊断提供有价值的信息.