Cystecercosis.

1-The most common CNS parasitic infection.

2-It is caused by taenia solium.

3-Stages of infection:
-First, the lesion characterized by severe inflammatory reaction surrounded by severe edema.
-Then, followed by formation of what is like an abscess, in this stage,its differentials is tuberculoma.
-Finally result in intra cranial calcification even if the patient received treatment.
-The only stage where you can diagnose cysticercosis is when you see cyst with a dot sign(Best see in T1 image) in which you see multiple small cysts in the brain parenchyma with dots inside it. It is not necessary to see these dots in all cysts but enough to see them in some of cysts to diagnose cysticercosis.