severe hand pain

Since my daughter was 9y/o she has experienced episodes of hand pain that would come on without any warning or any common precursor. She has under gone mmultiple medical test mri, ct, emgs all of which were negative.  for three years now her symptoms were treated as seizures.  Sheis now15 years old and the occurences of episodes have increased gradually over time when she was young to a few a week to a few a day,  now in the last few weeks she had upwards of 50 in a few hours.  The pain imobolizers her hand causes severe pain.  She was treated over night  with a video EEG and it was determined that she was not having seizures after all however the PET she had showed multiple lesions in the sensory cotext of her brain.  She is above average intelligence. THe doctors seem baffled where do we go from here?