DWI和ADC值测量在颅内囊性病变鉴别诊断中的价值

Study of DWI and ADC Value in Distinguishing of Brain Cystic Lesions

目的:评价DWI与ADC值对颅内囊性病变的鉴别诊断价值以及相关的生物物理学机制。方法:经手术病理证实的脑脓肿20例、囊变坏死性脑肿瘤50例、表皮样囊肿20例和蛛网膜囊肿35例,在术前均接受了常规MRI和DWI检查。结果:脑脓肿在DWI上表现为明显的高信号,ADC值为(0.67±0.178)×10-3mm2/s;脑肿瘤囊变坏死灶在DWI上表现为明显的低信号,ADC值为(2.48±0.156)×10-3mm2/s,脑脓肿ADC值明显低于脑肿瘤囊变坏死灶ADC值(P<0.01)。表皮样囊肿在DWI上表现为明显的高信号,ADC值为(1.19±0.157)×10-3mm2/s;蛛网膜囊肿在DWI上表现为明显的低信号,ADC值为(3.01±0.321)×10-3mm2/s,表皮样囊肿ADC值明显低于蛛网膜囊肿ADC值(P<0.01)。结论:DWI和ADC值测量可有效鉴别脑脓肿与囊变坏死性脑肿瘤;DWI和ADC值测量能有效鉴别表皮样囊肿和蛛网膜囊肿。

Objective：To investigate the value of DWI and ADC value in distinguishing brain cystic lesions and related biophysical mechanism. Methods： 20 patients with brain abscess, 50 patients with cystic or necrotic of brain tumor, 20 patients with epidermoid cyst,and 35 patients with arachnoid cyst confirmed histologically were examined before operations using conventional MRI and DWI. Results： On DWI, the brain abscess showed marked high signal intensity, its ADC value being （0.67 ± 0. 178）×10^-3 mm^2/s. The cystic or necrotic area of brain tumor presented low signal intensity, its ADC value being （2.48±0. 156）×10^-3mm^2/s. The brain abscess ADC value was lower than that of the cystic or necrotic area of brain tumor and there was significant difference between them （P〈0.01）. The epidermoid cyst showed marked high signal intensity,the epidermoid cyst ADC value being （1. 19±0. 157） ×10^-3mm^2/s. The arachnoid cyst presented low signal intensity, the arachnoid cyst ADC value being （3. 01 ± 0. 321）×10 ^3 mm^2/s. Epidermoid cyst ADC value was lower than that of arachnoid cyst ADC value and there was significant difference between them （P〈0.01）. Conclusion： The DWI and the measurement of ADC value can distinguish between the brain abscess and the cystic or necrotic area of brain tumor and between the epidermoid cyst and the arachnoid cyst effectively.