Meningitis

1-Meningitis could be viral, bacterial or granulomatous.

2-Basically, to diagnose meningitis you should inject contrast.

3-Usually, you see enhancement of basal cistern, lepto-meninges.

4-From the results of CT and MRI we can not know the cause of meningitis.

5-If you find in addition to meningitis a brain abscess, you can conclude that the cause of meningitis is bacterial.

6-Meningitis could affects the brain parenchyma, and ventricles.

7-If it affects the brain parenchyma, it could cause cerebritis if the causative agent is bacterial or encephalitis if it is viral.

Then it could spread to the ventricles causing ventriculitis.

8-Meningitis could cause vascular thrombosis of dural sinuses leading to venous infarction.

9-One of the most common complication of meningitis is hydrocephalus.

10-Meningitis could lead to epi dural and or sub dural empyema.

11- Meningitis could be subtle in the CT or MRI (minimal enhancement), in such a case and every case you should depend upon clinical to diagnose meningitis.

12-If the infection spreads from meninges to the brain parenchyma, this condition known as meningo-encephalitis.

13-All collections arising within the falx are sub dural collection.

14-Sub dural empyema when resolved it leads to formation of sub dural hygroma.