Department of Neurology, Nara Medical University, Kashihara, Nara, Japan.
J Neuroimaging. 2011 Apr;21(2):e69-77. doi: 10.1111/j.1552-6569.2010.00502.x.
Features of tumefactive demyelinating lesion (TDL) on magnetic resonance imaging (MRI) can facilitate the differential diagnosis of TDL and neoplastic lesions, but vary considerably among patients. The larger TDL grows, the more difficult it becomes to differentiate TDL from neoplastic lesions. The purpose of this study was to elucidate typical MRI features in 12 patients with large TDL (>30 mm in diameter).
We identified 12 patients with large TDL (six men, six women; age range 17-64 years, median age 27 years) and studied the clinical histories and the results of laboratory and various radiological studies in these patients. All cases of clinically definite multiple sclerosis were diagnosed in accordance with McDonald's revised criteria.
Common MRI features of large TDLs included variable degrees of mass effect (71%) and edema (100%), a T2 hypointense rim (79%), venular enhancement (57%), and peripheral restriction on diffusion-weighted images (50%). Ring enhancement (38%), open-ring enhancement (31%), or decreased N-acetylaspartate ratios on magnetic resonance spectroscopy (22%) were less frequently observed. Brain angiography demonstrated venous dilatations on and around the TDL.
The diagnosis of large TDL is challenging. Our findings suggest that multiple venous dilatations on and around TDLs on angiography can facilitate diagnosis.
磁共振成像（MRI）上肿块样脱髓鞘病变（TDL）的特征有助于TDL 和肿瘤性病变的鉴别诊断，但在患者之间存在很大差异。TDL 越大，其与肿瘤性病变的鉴别就越困难。本研究的目的是阐明 12 例大型 TDL（直径>30mm）患者的典型 MRI 特征。
我们确定了 12 例大型 TDL（6 例男性，6 例女性；年龄 17-64 岁，中位年龄 27 岁）患者，并研究了这些患者的临床病史以及实验室和各种影像学研究结果。所有临床确诊的多发性硬化病例均按照 McDonald 修订标准进行诊断。
大型 TDL 的常见 MRI 特征包括不同程度的占位效应（71%）和水肿（100%）、T2 低信号环（79%）、静脉增强（57%）和弥散受限的外周受限（50%）。环形增强（38%）、开环增强（31%）或磁共振波谱上 N-乙酰天门冬氨酸比值降低（22%）较少见。脑血管造影显示 TDL 及其周围的静脉扩张。
大型 TDL 的诊断具有挑战性。我们的研究结果表明，血管造影上 TDL 及其周围的多发静脉扩张有助于诊断。
