DWI在颅内囊性病变鉴别诊断中的价值

目的 探讨磁共振扩散加权成像（DWI）对颅内囊性病变的鉴别诊断价值。方法 回顾性分析102例临床及手术病理证实的颅内囊性病变（脑脓肿9例、胶质瘤25例、转移瘤19例、蛛网膜囊肿25、表皮样囊肿24例）患者的DWI信号特征及囊变坏死区表观扩散系数（ADC）。结果 9例脑脓肿中6例呈高信号，3例呈高低混杂信号；25例胶质瘤中，3例呈高低混杂信号，其余22例均为低信号；19例脑转移瘤中，单发病灶中1例为高信号，15例为低信号；3例多发病灶中，部分为高信号，部分为低信号；25例蛛网膜囊肿均呈低信号；24例表皮样囊肿均呈明显高信号。脑脓肿患者ADC值明显低于囊变坏死性脑肿瘤患者，P〈0．01；表皮样囊肿患者ADC值明显低于蛛网膜囊肿患者，P〈0．01。结论 DWI在脑脓肿和囊变坏死性脑肿瘤及蛛网膜囊肿与表皮样囊肿的鉴别诊断中具有重要价值。

Value of DWI in the differential diagnosis of intracranial cystic lesions

Objective To investigate the value of DWI in the differential diagnosis of intracranial cystic lesions. Methods One hundred and two patients with intracranial cystic lesions confirmed by clinical manifestation and surgical pathology （9 abscesses, 25 glioblastomas, 19 metastases,25 arachnoid cysts,24 epidermoid cysts）were enrolled , the signal characteristics of which on DWI and the ADC values of cystic areas were analysed. Results Six of the brain abscesses showed high signal and 3 cases showed mixed signal on DWI. Among 25 cases of brain gliomas, 3 cases showed mixed signal, the rest were of low signal. About 19 cases of brain metastases, 1 was high signal and 15 were low signal among solitary cases ,3 multiple cases showed low signal and high signal respectively. 25 intracranial arachnoid cysts showed low signal and 24 epidermoid cysts showed obviously high signal on DWI. The ADC values of cases with brain abscess were significantly lower than those of the cases with cystic or necrotic portions of brain tumor, P 〈 0.01 . The ADC values of cases with arachnoid cyst were significantly lower than that of the cases with epidermoid cyst,P 〈 0.01. Conclusions DWI is of great value in the differential diagnosis of brain abscesses and cystic or necrotic tumors, also of the arachnoid cyst and epidermoid cyst.