Abstract:
We investigated the reduction in regional brain volume and cerebral blood flow (CBF) with aging and explored potential sex differences in healthy brains. Three-dimensional (3D) T1-weighted magnetic resonance imaging (MRI), time-of-flight magnetic resonance angiography, and four-dimensional (4D) flow MRI were performed on 129 healthy volunteers aged 22-92 years. The brains of healthy volunteers were segmented into 21 subregions using 3D T1-weighted MRI and CBFs in 16 major intracranial arteries were measured using 4D flow MRI. The cortical gray matter volume decreased linearly with aging, whereas the cerebral white matter volume increased until the 40s and then decreased, and the subcortical gray matter volume changed little with aging. The cortical gray matter volume was significantly associated with the total CBF of the major intracranial arteries distal to the circle of Willis; however, the cerebral white matter and subcortical gray matter volumes were not. Generally, women have higher total CBF than men, particularly in their 40s and younger, despite the smaller intracranial volume and smaller diameters of intracranial arteries than men. This may contribute to the higher incidence of subarachnoid hemorrhage due to cerebral aneurysms and migraine in women.
摘要:
我们调查了随着年龄的增长,局部脑容量和脑血流量(CBF)的减少,并探索了健康大脑中潜在的性别差异。三维(3D)T1加权磁共振成像(MRI),飞行时间磁共振血管造影术,对129名年龄在22-92岁的健康志愿者进行了四维(4D)流MRI。使用3DT1加权MRI将健康志愿者的大脑分为21个子区域,并使用4D流量MRI测量16个主要颅内动脉的CBF。皮质灰质体积随老化呈线性下降,而脑白质体积增加到40年代,然后减少,皮质下灰质体积随老化变化不大。皮质灰质体积与Willis环远端主要颅内动脉的总CBF显著相关;然而,大脑白质和皮质下灰质体积没有。一般来说,女性的总CBF比男性高,特别是在40多岁和更年轻的时候,尽管颅内体积和颅内动脉直径比男性小。这可能导致女性脑动脉瘤和偏头痛引起的蛛网膜下腔出血的发生率更高。