How common are arachnoid cysts?

How common are arachnoid cysts?

Arachnoid cysts are the most common kind of brain cyst. They affect people of all ages, but they arise in babies and children. Males are four times more likely to develop an arachnoid cyst than females.

Healthcare providers don’t know how many people get arachnoid cysts. Most arachnoid cysts develop without causing symptoms and are found accidentally when the head is scanned for other reasons. So, it’s nearly impossible to know how many people have them.