颅内原发性淋巴瘤DWI及PWI表现

目的 探讨颅内原发性淋巴瘤扩散加权成像(DWI)和灌注加权成像(PWI)特点.方法 回顾性分析10例颅内原发性淋巴瘤的DWI表现和9例颅内原发性淋巴瘤的PWI特征,所有病例均经病理证实,并结合其病理特征与高级别(Ⅲ、Ⅳ级)星形细胞瘤作对照.结果 颅内原发性淋巴瘤DWI多呈均匀高信号,肿瘤实质ADC值为(79.73±10.21)×10-5mm2/s,明显低于高级别星形细胞瘤ADC值(99.81±19.57)×10-5mm2/s(P=0.002).9例行PWI检查,颅内原发性淋巴瘤肿瘤实质最大rCBV比值为1.71±0.59,而14例高级别星形细胞瘤肿瘤实质最大rCBV比值为5.17±1.73,与高级别旱形细胞瘤比较,颅内原发性淋巴瘤呈低灌注趋势(P=0.001).结论 颅内原发性淋巴瘤DWI、PWI具有一定的特征,术前行DWI、PWI有助于提高MRI对颅内原发性淋巴瘤的诊断水平.

Diffusion-weighted imaging and perfusion-weighted imaging findings of primary intracranial lymphoma

objective To study diffusion weighted magnetic resonance imaging(DWI)and perfusion weighted magnetic resonance imaging(PWI)features of primary intracranial lymphoma.Method The DWI features were retrospectively analyzed in 10 cases of primary intracranial lymphoma proved by operation and pathology,while PWI features of 9 cases were retrospectively studied.The comparison with 21 cases of high grade(Ⅲ,Ⅳ) astrocytomas were performed in combination with their histopathological characteristics.Results The lesions of primary intracranial lymphoma usually showed high signal on DWI,and the apparent diffusion coefficient(ADC)value of primary intracranial lymphoma was(79.73±10.21)×10-5mm2/s,and the comparison with a group of high grade astrocytomas showed a statistical significance in the ADC value(99.81 ±19.57)×10-5 mm2/s(P=0.002).PWI features showed that the maximum rCBV ratio of primary intracranial lymphoma in tumor parenchyma was 1.71±0.59,while that of high grade astrocytomas was 5.17±1.73.The primary intracranial lymphoma had a tendency to have low perfusion compared with high grades astrocytomas(P=0.001).Conclusions DWI and PWI can be useful in distinguishing primary intracranial lymphoma from high grades astrocytomas.Combining with the conventional MRI appearance with DWI and PWI features can improve MRI diagnostic accuracy of primary intracranial lymphoma.