question: In the report from a CT scan I had in 2003, it was stated that situated over my right frontal lobe , anterior in its mid portion, I have a low density CSF density lesion which measures about 3.3cm in width and 1.1cm in depth. The report said it was typical of an arachnoid cyst . I have difficulty with my memory , which although I have always been able to mask from my colleagues as I have systems to assist me, I feel it is getting progressively worse. Could this be caused by the above? If such a mass is occupying a space that opperational parts of my brain should be occupying surely this would have some affect. I was dismissed and told it was fine when I received the report but I have always had unanswered questions.