动态磁敏感增强灌注成像对假瘤样脱髓鞘病的诊断价值

Diagnostic value of dynamic susceptibility T2 ^＊-weighted contrast-enhanced perfusion MR imaging for pseudotumor demyelinating lesion

目的探讨应用动态磁敏感T2*加权对比剂增强灌注MR成像(dynamicsu sceptibility T2*-weighted contrast-enhanced perfusion MR imaging,DSC-MRI)对中枢神经系统假瘤样脱髓鞘病的诊断价值。方法回顾性分析2例经手术证实和7例经临床证实的假瘤样脱髓鞘病MRI灌注成像(perfusion-weighted imaging,PWI),将病灶直径>2cm的共12个病灶纳入研究对象,分析其最大相对局部脑血容量(rCBV)、最大相对局部脑血流量(rCBF)及最大相对局部平均通过时间(rMTT),并与12个颅内脑白质区恶性肿瘤的相应灌注值作为对照研究。结果假瘤样脱髓鞘病组rCBV、rCBF、rMTT分别为(1.17±0.32)、(1.09±0.23)、(1.12±0.40);对照组rCBV、rCBF、rMTT分别为(4.41±2.86)、(2.25±0.64)、(2.06±1.25),两组各灌注值比较有显著性差异(P<0.05)。结论用MRI的灌注成像对鉴别假瘤样脱髓鞘病和颅内恶性肿瘤具有较大价值。

Objective To evaluate the diagnostic value of dynamic susceptibility T2 -weighted contrast-en- hanced perfusion MR imaging for pseudotumor demyelinating lesion in the central neuronal system. Methods Totally 2 pathologically proved cases and 7 clinically proved cases of pseudotumor demyelinating lesions in the central neuronal system were retrospectively analyzed with dynamic susceptibility T2-weighted contrast-en- hanced perfusion MR imaging, and there were 12 lesions included which diameters were all more than 2 cm. The maximum relative regional cerebral blood volume （rCBV）, the maximum relative regional cerebral blood flow （rCBF）, and the maximum relative regional mean transit time（rMTY） were calculated according to perfusion MR data. The perfusion values from 12 patients with intracranial neoplasms served as control, which have very similar features of pseudotumor demyelinating lesions from conventional MR images. Results The rCBV, rCBF and rMTT mean values of pseudotumor demyelinating lesions were （ 1.17 ± 0.32）, （ 1.09 ± 0.23 ） and （1.12± 0.40） respectively; the rCBV, rCBF and rMTT mean values of intracranial neoplasms were （4.41 ± 2.86）, （2.25 ±0.64） and （2.06 ± 1.25） respectively; the difference in rCBV, rCBF and rMTTvalues be- tween the 2 groups was statistically significant respectively （P 〈 0.05）. Conclusion Dynamic susceptibility T2 -weighted contrast-enhanced perfusion MR imaging is a useful diagnostic tool in differentiating pseudotumor demyelinating lesions from intracranial neoplasms.