上矢状窦内起源脑膜瘤的影像解剖依据

目的　通过MRI分析正常成人上矢状窦（superior sagittal sinus，SSS）内蛛网膜颗粒（arachnoid granules，AG）的影像学分布，同时分析上矢状窦旁脑膜瘤（parasagittal meningiomas，PSM）临床资料，探讨窦内起源脑膜瘤的解剖依据。 方法　收集100例排除脑器质性病变的各年龄段头颅MRI常规及增强扫描资料，统计SSS内AG的分布及大小，本研究称为AG组。收集本科室2013年1月至2018年8月PSM患者30例的MRI资料及手术情况，特别关注疑似SSS内PSM的影像特点和起源位置，本研究称为PSM组。 结果　AG组100例中有32例MRI能够辨认SSS内AG，其中在SSS前1/3段发现6个AG，中1/3段发现24个，后1/3段发现11个。分析30例PSM患者的MRI特点，发现符合SSS内脑膜瘤者5例，其中位于SSS中1/3段2例，后1/3段3例；均手术治疗并随访24~33个月，无肿瘤复发。两组比较，窦内AG的分布与窦内脑膜瘤好发部位相仿，肿瘤的影像学形态符合窦内生长规律。 结论　PSM并非都是窦旁起源的，少部分可能起源于SSS内的AG，MRI显示以窦内纵向扩展为主、两侧对称性扩展为辅的特征，可予定义为“SSS脑膜瘤”。

The imaging anatomical basis of meningioma in the superior sagittal sinus

Objective　To provide the anatomical basis for superior sagittal sinus (SSS) meningioma by analyzing the distribution of arachnoid granules (AG) in the superior sagittal sinus and the clinical data of parasagittal meningiomas (PSM).　Methods　Conventional MRI and enhanced MRI data of 100 patients of all ages excluding organic brain lesions were collected, which were named as AG group. The distribution and size of AG in SSS were analyzed . From January 2013 to August 2018, 30 cases of PSM patients information which including the corresponding patients imaging characteristics and origin location in SSS were recorded. This group was named as PSM group.　Results　There were 32 cases which can recognize AG in the superior sagittal sinus of the AG group, including 6 cases of AG in the anterior 1/3 SSS, 24 cases of AG in the middle 1/3 SSS and 11 cases of AG in the posterior 1/3 SSS. There were 5 cases with meningioma in the superior sagittal sinus of the PSM group, including 2 cases in the middle of the superior sagittal sinus and 3 cases in the back of the superior sagittal sinus. All patients were treated by surgery and followed up for 24~33 months, without tumor recurrence. The distribution of AG in the sinuses was similar to that of meningioma in the sinuses, and the imaging morphology of the tumor accorded with the growth rule in the sinuses. Conclusions　Not all PSM originates from the paranasal sinus, only a few of them may originate from the AG in the SSS. Parasagittal meningiomas, which are characterized by roughly symmetrical expansion to both sides, can be defined as “SSS meningiomas”.