Steffey D J, De Filipp G J, Spera T, Gabrielsen T O
Department of Radiology, University of Michigan Hospitals, Ann Arbor 48109-0030.
J Comput Assist Tomogr. 1988 May-Jun;12(3):438-40. doi: 10.1097/00004728-198805010-00016.
The magnetic resonance (MR) imaging characteristics of five primary intradural epidermoid tumors are described. At 0.35 T, the most consistent finding on spin echo imaging was a tumor signal intensity that differed from brain and CSF. On T1-weighted images [repetition time (TR) 0.5 s, echo time (TE) 30-40 ms] all tumors exhibited a signal intensity intermediate between brain and CSF. On moderately T2-weighted images (TR 2.0 ms, TE 60-80 ms) the tumor signal intensity was greater than brain and CSF in all cases. The tumor signal consistency was mixed in four of five lesions and homogeneous in one. The tumor margins were well defined in all cases; in three cases the tumor margins were irregular, in one case smooth, and in the last case, one margin was irregular and the remaining margins were smooth. These findings are contrasted with the MR appearance of arachnoid cysts. Using identical imaging factors, four arachnoid cysts were studied and exhibited a homogeneous signal intensity that was identical to CSF on all pulse sequences; their margins were smooth and well defined in each case. These MR findings contribute to the characterization of extraaxial lesions.
描述了5例原发性硬脊膜内表皮样肿瘤的磁共振（MR）成像特征。在0.35T时，自旋回波成像最一致的表现是肿瘤信号强度与脑和脑脊液不同。在T1加权像上[重复时间（TR）0.5秒，回波时间（TE）30 - 40毫秒]，所有肿瘤的信号强度介于脑和脑脊液之间。在中等T2加权像上（TR 2.0毫秒，TE 60 - 80毫秒），所有病例中肿瘤信号强度均高于脑和脑脊液。5个病灶中有4个的肿瘤信号一致性为混合性，1个为均匀性。所有病例中肿瘤边界均清晰；3例肿瘤边界不规则，1例边界光滑，最后1例中，1个边界不规则，其余边界光滑。这些表现与蛛网膜囊肿的MR表现形成对比。使用相同的成像参数，研究了4例蛛网膜囊肿，其在所有脉冲序列上均表现出与脑脊液相同的均匀信号强度；每例囊肿边界均光滑且清晰。这些MR表现有助于对轴外病变进行特征性描述。
