We could hit the middle cerebral artery.

我们会碰到他的大脑中动脉。

The vision is lost in halves that are contralateral to the posterior cerebral artery that is affected.

视野缺失会发生在受影响的大脑后动脉的对侧。

The displaced part of the brain can compress the anterior cerebral artery, and that can cause an ischemic stroke.

大脑移位的部分会压迫大脑前动脉，可导致缺血性脑梗死。

This is because the part of the occipital lobe in charge of the macula gets blood from both the posterior cerebral artery as well as the medial cerebral artery.

这是因为负责黄斑功能的枕叶部分同时由大脑后动脉和大脑中动脉供血。

The posterior cerebral artery can also be compressed, which results in ischemic stroke of the occipital part of the brain, which is responsible for processing of visual information.

另外，大脑后动脉也会受到压迫，导致大脑枕部缺血性脑梗死；大脑枕部区域本来负责视觉信息的处理。

One theory might be that, there is a spasm in one of the cerebral arteries, and that reduces the flow of blood and causes a localized lack of oxygen.

一种理论可能是，其中一条大脑动脉发生痉挛，这会减少血液流动并导致局部缺氧。