Department of Imaging Sciences and Interventional Radiology, Sree Chita Tirunal Institute for Medical Sciences and Technology, Medical College, Trivandrum, India.
J Neuroradiol. 2010 Jul;37(3):167-71. doi: 10.1016/j.neurad.2009.08.005. Epub 2009 Sep 24.
As both tuberculoma and metastasis can manifest as solitary or multiple ring-enhancing intra-axial lesions that are difficult to differentiate by conventional magnetic resonance imaging (MRI), we hypothesized that the use of diffusion and perfusion MRI would make differentiation of these pathologies possible.
Diffusion and T2*-weighted dynamic contrast-enhanced perfusion MRI scans from 11 patients with histologically proven tuberculoma or metastasis were retrospectively reviewed by two radiologists who were blinded to the pathology. All patients had a ring-enhancing lesion on conventional MRI. Apparent diffusion coefficient (ADC) values and regional cerebral blood volume (rCBV) were calculated from the walls of the lesions.
Lesions showed different perfusion characteristics depending on whether they were due to tuberculosis or metastasis. The mean rCBV ratio between the lesion periphery and normal white matter was inferior to one for tubercular lesions and greater than five for metastases. However, ADC values were similar.
Measuring rCBV obtained by T2*-weighted dynamic contrast-enhanced perfusion MRI can help in differentiating intracranial tubercular mass lesions and metastases.
结核瘤和转移瘤均可表现为单发或多发的环增强脑内轴内病灶，常规磁共振成像（MRI）难以鉴别，我们假设扩散和灌注 MRI 的应用可使这些病变得到鉴别。
回顾性分析了 11 例经组织学证实的结核瘤或转移瘤患者的扩散和 T2*-加权动态对比增强灌注 MRI 扫描，两位放射科医生对这些患者的病理结果不知情。所有患者在常规 MRI 上均显示为环形增强病灶。从病灶壁计算表观扩散系数（ADC）值和局部脑血容量（rCBV）。
病灶的灌注特征因病变是由结核还是转移引起而不同。结核病灶的病灶周边与正常白质之间的平均 rCBV 比值小于 1，转移病灶的比值大于 5。然而，ADC 值相似。
测量 T2*-加权动态对比增强灌注 MRI 获得的 rCBV 有助于鉴别颅内结核肿块病变和转移瘤。
