Hello Doctor, my mother has been suffering from severe dizziness from last 8 days. she cannot even sit on bed due to dizziness.when she is lying on bed then it is better but once she tries to get up severe dizziness occurs.she had undergone brain tumour surgery in 2004 but her MRI report is normal and her neck xray is also normal along with all her blood reports including CBC, blood sugar, urea cretinine etc .There are no other symptoms showing on her except for the severe dizziness.please suggest me with proper diagnosis. thank you.