Hi Alegre17,
I have an Arachnoid Cyst that had doubled in size in the past 8 years. I attribute a fair few of my issues at least partially to it. Unfortunately, here they are ignored unless they seem so large they malform the skull. I am afflicted by Idiot Neuro Syndrome

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Have you been given any surgical options? Do you have seizures or any other symptoms? I know exactly how worrying a growth in the brain can be, and talk of surgery is particularly worrying. The brain is the centre of yourself, the very essence of being 'you',. Should you feel the need to talk about any Cyst issues I am always available.
Dave.