MRI在诊断退变期脑实质型脑囊虫病同小转移瘤的鉴别价值

目的：通过常规MRI序列与DWI序列，鉴别退变期脑实质型脑囊虫病与小病灶环形强化转移瘤。方法回顾29例脑囊虫病患者与30例多发小病灶转移瘤患者的M R检查，观察两者的影像学表现及测量ADC值进行统计学处理。结果常规T2 WI退变期脑囊虫病组和小转移瘤组病灶出现低信号环的比例分别为91．9％和9．1％，诊断敏感性为90．7％（78/86）、特异性90．9％（60/66）、准确性90．8％（138/152）；DWI退变期脑囊虫病组和转移瘤组病灶出现低信号所占比例分别为95．4％和69．7％，诊断敏感性95．4％（82/86）、特异性30．3％（20/66）、准确性67．1％（102/152）。退变期脑囊虫组病灶ADC值（1．54±0．42）×10^-3 s/mm^2，脑转移瘤病灶组ADC值（1．12±0．36）×10^-3 s/mm^2，两者比较具有统计学差异（ P ＜0．01）。结论 T2 WI病灶周围连续的低信号和完整规则的环形强化是退变期脑囊虫病的特殊表现。DWI序列对退变期脑囊虫病和小病灶转移瘤的鉴别具有一定的价值。

Value of convertional MRI in detecting degenerative phase of cerebral cysticerlosis and small metastases

Objective To study the difference of degeno-death stage cerebral neurocysticercosis lesions and brain metastasis nodules through the conventional MR scan and DWI sequence .Methods MRI data of 29 patients with degeno-death stage cerebral neurocysticercosis and 30 patients with brain metastasis were reviewed .The imaging features were studied and the ADC value of the lesions ,were measured with spss 16 .0 statistical software as data analysis .Results 91 .9% lesions of degeno-death stage cerebral nerocyticercosis displayed surrounding hypointense signal on T2 WI ,while ,the brain metastasis nodules was 9 .1% .The diagnostic sensitivety ,specificity and accuracy of T2WI low signal intensity surround-ing were 90 .7% （78/86） ,90 .9% （60/66） and 90 .8% （138/152） respectively .Among those ,95 .4% lesions of degeno-death stage cerebral nerocyticercosis were shown hypointense signal on DWI while the brain metastasis nodule was 69 .7% . The diagnostic sensitivety ,specificity and accuracy of hypointense signal on DWI were 95 .4% （82/86） ,30 .3% （20/66） and 67 .1% （102/152） respectively .The mean ADC value of degeno-death stage cerebral nerocyticercosis was （1 .54 ± 0.42） ×10^- 3s/mm^2 and the brain metastasis nodule lesion was （1 .12 ± 0 .36） ×10^- 3s/mm^2 .There was a significant difference between two of them （ P 〈0 .01） .Conclusion The consistent hypointense signal ring and the integrity regular en-hancement are the characteristic of degeno-death neurocysticercosis lesions .DWI and ADC values are valuable to differenti-ate the degeno-death neurocysticercosis lesions from the brain metastasis nodule lesions .