CSF Production

1- Is produced by choroid plexus in the ventricles especially in the lateral ventricles.

2-It passes from the lateral ventricles through foramen of Monro to the third ventricle, then from the third ventricle to the fourth ventricle through the aqueduct of sylvius where it reaches the fourth ventricle, then from the fourth ventricle to the sub arachnoid spaces through outlet foramina.

3-Then, absorbed by arachnoid villi and returned to the venous system via superior sagital sinus.

4-It excrete by a rate of 500 ml per day.