脑囊虫病的MRI诊断及病理分析

MRI diagnosis and pathological analysis of cerebral cysticercosis

目的分析脑囊虫病的病理演变特点,探讨脑囊虫病的MRI特征及诊断价值。方法分析36例脑囊虫病的MRI表现特点,并结合12例手术后病理材料进行比较。结果脑实质型18例,脑室型4例,脑膜型3例,混合型11例,主要MRI特点:①囊虫存活期,病灶呈圆型,多发常见,附壁囊虫头节呈偏心型小点状影,T1WI呈略高信号,T2WI呈中低信号;囊液T1WI呈低信号,T2WI呈高信号;在FLAIR上脑脊液呈低信号,而囊液呈相对高信号;周围水肿不明显。②囊虫退变坏死期,头节消失,囊腔扩大,周围水肿明显。③病灶钙化后,T1WI及T2WI均呈低信号,周围水肿消失。④增强扫描,表现为:囊壁环状增强(24/36),或不增强(12/36);囊内小点状影增强(22/36),或不增强(14/36)。⑤脑室型常发生于三、四脑室,其中三脑室1例(1/36),四脑室3例(3/36),均引起阻塞性脑积水。⑥脑膜型因蛛网膜粘连,而引起脑积水(2/36)。结论脑囊虫病在病理演变过程中,具有特征性的MRI表现;MRI对确定脑囊虫病的数目、大小、部位等发病特点及病理演变过程具有很高的诊断价值。

Objective To analyze the pathological and developmental characteristics of cerebral cysticercosis （CC） and to explore the MRI features and diagnostic value of CC. Methods The MRI findings of 36 cases with CC were analyzed and compared with the postoperative pathological materials of 12 patients. Results Of 36 cases, 18 were cerebral-parcnchymal type, 4 cerebral-ventricular type, 3 meningeal type, and 11 were mixed type. The main characteristics of MRI were as follows： ① frequently-encountered multiple circular loci during the cysticercus survival： small excentric spotty shadow of the mural cysticercus scolex, slightly high signs on T1WI and middle-lower signs on T2WI; capsular liquid werclower signs on T1WI and high signs on T2WI; lower signs of the cerebrospinal fluid, but relatively high signs of the capsular liquid on FLAIR; and unremarkable peripheral edema; ② scolex disappearance, enlarged capsular cavity and remarkable peripberal edema during cysticercus degeneration and necrosis; ③lower signs on T1WI and T2WI and peripheral edema disappearance after the focal calcification; ④ findings showed by the enhanced scanning： strengthened （24/36） or non-strengthened （12/36） cyst-wall circular images; strngthened （22/36） or non-strengthened （14/36） small intracapsular spotty shadow; ⑤ cerebral-ventricular type often occurred in the third and fourth ventricles： one case in the third ventricle （1/36） and three cases in the fourth ventricle （3/36）, all of which suffered obstructive hydrocephalus; ⑥hydrocephalus caused by arachnoid adhesion （2/36） in meningeal type. Conclusion During the pathological development, CC has characteristic MRI findings, which is of great diagnostic value to determining the pathogenic characteristics, such as the number, size, location, etc, and to the pathological developmental process of CC.