I'm a 29 year old female who had a Cavernous Malformation removed from my right frontal Lube in January 2010. Now my 27 year old sister was just diagnosed with a Arachnoid Cyst in her left frontal lube. I was just wondering what are the odds that two sisters would be diagnosed with something in their Brian with in a year of each other. I know that nether conditions have anything to do with each other. I was just thought that this was odd.