扩散加权成像与表观扩散系数值测量在颅内囊性病变鉴别中的应用

Value of diffusion weighted imaging and apparent diffusion coefficient values to the differentiation of intracranial cystic diseases

目的:评价扩散加权成像与表观扩散系数值鉴别诊断颅内囊性病变的价值。方法:12例脑脓肿、34例坏死囊变性肿瘤、10例表皮样囊肿、12例蛛网膜囊肿和5例脑囊虫病患者行常规MRI及扩散加权成像检查,分别测量其囊变区平均表观扩散系数值。结果:扩散加权成像上10例脑脓肿呈高信号,2例低信号;26例坏死囊变性肿瘤呈低信号,3例稍高信号,5例混杂信号;8例表皮样囊肿呈高信号,2例为低信号;12例蛛网膜囊肿及5例脑囊虫均呈低信号。脑脓肿、坏死囊变性肿瘤、表皮样囊肿、蛛网膜囊肿和脑囊虫囊变区平均表观扩散系数值分别为:(0.63±0.20)×10-3mm2/s,(2.45±0.16)×10-3mm2/s,(1.21±0.39)×10-3mm2/s,(2.98±0.23)×10-3mm2/s和(2.25±0.38)×10-3mm2/s。脑脓肿与坏死囊变性肿瘤囊变区之间,表皮样囊肿与蛛网膜囊肿囊变区之间以及表皮样囊肿与脑囊虫囊变区之间的平均表观扩散系数值间差异有统计学意义(P<0.01),蛛网膜囊肿与脑囊虫囊变区之间的平均表观扩散系数值间差异无统计学意义(P>0.05)。结论:扩散加权成像和表观扩散系数值有助于颅内囊性病变的鉴别诊断。

Objective To evaluate the differentiation value of diffusion weighted imaging and apparent diffusion coefficient values to intracranial cystic diseases. Methods The mean apparent diffusion coefficient values were respectively measured in 12 cases of brain abscess, 34 of necrotic- cystic intracranial tumor, 10 of epidermoid cysts, 12 of arachnoid cyst and 5 of cerebral cysticercosis which were verified using conventional MRI scanning and diffusion weighted imaging. Results In the cases of brain abscess, 10 showed high signal intensity and 2 displayed low signal intensity. In the cases of necrotic-cystic intracranial tumor, 26 demonstrated low signal intensity, 3 appeared slight high signal intensity and 5 showed farraginous signal intensity. In the cases of epidermoid cysts, 8 showed high signal intensity and 2 displayed low signal intensity. In the cases of arachnoid cyst, 12 displayed low signal intensity and 5 of cerebral cysticercosis displayed low signal intensity on diffusion weighted imaging. The mean apparent diffusion coefficient values of brain abscess, necrotic-cystic intracranial tumor, epidermoid cysts, arachnoid cyst and cerebral cysticercosis were （0. 63± 0. 20） ×10-3mm2/s, （2.45±0. 16） ×10-3 mm2/s, （1.21±0. 39） ×10- 3 mm2/s, （2. 98±0. 23） ×10-3 mm2/s and （2. 25±0.38） ×10- 3 mm2/s. The difference of mean apparent diffusion coefficient values of brain abscess and necrotic-cystic intracranial tumor, epidermoid cysts and arachnoid cyst, epidermoid cysts and cerebral cysticercosis had obvious statistic difference （P〈0.01）. There was no statistic difference between arachnoid cyst and cerebral cysticercosis（P〉0.05）. Conclusion Diffusion weighted imaging and apparent diffusion coefficient values can play an important role in differentiating intracranial cystic diseases.