I have been getting strange turns for 2yrs; dreamlike state, detachments,etc..then i get extremely tired for a few hours after. I was sent to have an MRI and they discovered a subarachnoid cyst with adjacent brian compression. I have also been vomitting, headaches, suicide tendancies ( which i have never had before ) i feel awful. But the neurosurgeon says that this has nothing to do with my cyst, my turns must be something else? I really dont understand this? I have been put on 100mg of lamotrigine which is not helping at all. I would like to know if adjacent brain compression is dangerous and what symptoms would this cause? as well as what is considered large with a subarachnoid cyst. Mine is located in the left frontal lobe. Any help would be welcomed.