Ishii K, Takahashi S, Matsumoto K, Ishibashi T, Sakamoto K, Hashimoto S, Katakura R, Ogawa A, Yuasa R
Department of Radiology, Tohoku University, Japan.
Radiat Med. 1996 Mar-Apr;14(2):65-9.
We reviewed the MR imaging findings of 57 acoustic neurinomas which were verified at surgery or diagnosed on the basis of neuroradiological and neurootological data. Two uncommon MR findings of acoustic neurinoma were found. First, hypointense areas were observed on T2-weighted images in five of the 12 tumors larger than 25 mm in diameter. These hypointense areas represented hemosiderin deposition secondary to occult intratumoral hemorrhage. Second, curvilinear or round signal voids were noted at the periphery of 11 large or medium-sized tumors, and these corresponded to "abnormal veins" seen on angiographic studies.
我们回顾了57例听神经瘤的磁共振成像（MR）表现，这些病例均经手术证实或根据神经放射学和神经耳科学数据确诊。发现了听神经瘤两种不常见的MR表现。首先，在12例直径大于25mm的肿瘤中，有5例在T2加权图像上观察到低信号区。这些低信号区代表隐匿性肿瘤内出血继发的含铁血黄素沉积。其次，在11例大中型肿瘤的周边发现了曲线形或圆形信号缺失，这些对应于血管造影研究中所见的“异常静脉”。
