This paper reports 25 cases with otogenous cerebral hernia

in which

13 were tentorial hernia

(10 inferior tentorid notch hernia

3superior tentorid notch hernia)

12 tonsillar hernia. We found that the predisposing factors of cerebral hernia were mastaidotomy Inmbal puncture

postural change and drainage of cerebral puneture

etc.Whenever the cerebral pressure of a patient with cerebral abscess is increased

one should avoid aforesaid factors in order to avoid the emergence of cerebral hernia incarceration.It is emphasized that once cerebral hernia emerged in patient. a measure of dehydrant should be taken as a preparatory step before opration