Raybaud C A, Strother C M
Department of Neuroradiology, Chu Timone, Marseille, France.
Acta Radiol Suppl. 1986;369:136-8.
The study of arterial and venous anatomy of hemispheric cerebral arteriovenous malformations (AVMs) shows that, beside occlusion, rerouting of the flow, and collateral supply and drainage, the arterial and venous patterns are normal. This can be explained by the fact that the cerebral hemispheres develop late relative to other neural structures, and their fetal vessels become in fact the permanent vessels. This normality indicates that the AVMs develop after the vascular pattern has been determined. Vein of Galen aneurysms, in contrast, demonstrate occasionally an abnormal arterial pattern over the hemisphere, and retention of an embryonic vein, the median prosencephalic vein. This indicates that the fistula occurred at a much earlier stage, actually when the choroid plexuses first developed, about the end of the second month. The occurrence of choroid AVMs similar to the vein of Galen aneurysms, but drained by a normal internal cerebral vein, indicates that the time when the choroid drainage is taken over the internal cerebral vein, represents another critical period.
对半球型脑动静脉畸形（AVM）的动静脉解剖学研究表明，除了闭塞、血流改道以及侧支供血和引流外，动静脉模式是正常的。这可以通过以下事实来解释：相对于其他神经结构，大脑半球发育较晚，其胎儿期血管实际上成为了永久性血管。这种正常性表明AVM是在血管模式确定后才发育的。相比之下，大脑大静脉瘤偶尔会在半球上显示出异常的动脉模式，并保留一条胚胎静脉，即前脑正中静脉。这表明瘘管发生在更早的阶段，实际上是在脉络丛首次发育时，大约在第二个月末。与大脑大静脉瘤相似但由正常大脑内静脉引流的脉络丛AVM的出现表明，脉络丛引流被大脑内静脉接管的时间是另一个关键时期。
