Pathological changes such as cortical gliosis, infarction and calcification, subcortical vacuolization, and abnormal enlargement of large cerebral veins and connection with many fine arteries. Brain injury occurs mainly by mechanisms such as arterial blood theft, cerebral ischemia secondary to heart failure, hemorrhagic infarction, lesion compression and surgical trauma. What is the daily prevention of cortical gliosis? The great cerebral vein originates from the venous reflux system that drains the intermediate structures of the choroid plexus. Initially, this vein does not communicate with the deep internal cerebral vein, and at about 11 weeks of embryonic development, the posterior part of the vein communicates with the internal cerebral vein to form the great cerebral vein, and the anterior part of the vein degenerates and eventually disappears. During the 6th to 11th week of embryonic development, if for some reason the embryonic development is abnormal and the anterior part of the cerebral veins do not degenerate and occlude properly, an arteriovenous fistula can be formed. Some patients may have subarachnoid hemorrhage, and the heart may be mildly enlarged. An intracranial murmur may be heard on cranial auscultation. However, it should be distinguished from the physiologic intracranial murmur in children. Generally, in normal infants or children, murmurs can also be heard in the skull or pars plana, with the ophthalmoplegia or temporal side being obvious. The murmur increases during systole and may disappear with compression of the carotid murmur. However, large cerebral venous tumor murmurs are evident near the parietal nodes and posterior midline, and are stronger in newborns and infants. They can be heard in both systole and diastole and may be continuous. Avoid predisposing factors. The prognosis of untreated large cerebral venous tumors is poor. Of the 92 untreated patients in the statistical literature, 77.2% died, 3.3% were disabled, 12% remained intact, and 7.5% were lost to follow-up. The main cause of death was cardiac and cerebral ischemic damage.