I tried to post a comment but it didn't work, so ill try again. 6 years ago my mother in law had a golfball sized cyst removed from the centre of her brain. The Dr explained how with the area he had to cut she might lose her short term memory for good. After a 9 hour operation, everything went well, and she went home a few days later. She made a complete recovery with absolutely no sign of any memory loss or other problems. Jeannine and I know first hand how scary this must be for you and your family. I wish your mom the best of luck and a speedy recovery! Keep us posted.