ministrokes and bells palsy

  My mother, who is eighty, woke today with the left side of her face
  drooping. She went to emergency where she was given a cat scan. No evidence
  of stroke discovered through cat scan, she was given a diagnosis of
  Bells Palsy. Coincidentally my mother mentioned to me yesterday her doctor
  gave her an mri years ago and discovered she had had ministrokes.
   My question is should not she have received an mri today considering her
   symptoms and past history; is it imperative she have one soon?
   Is a cat scan an adequate diagnostic tool- would it pick up damage to
  brainstem ?
  thanks in advance for any assistance you provide
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Dear Judy:
Although your grandmother may well have developed Bells palsy, and may also have evidence of "ministrokes" on a previous MRI (the two problems are unrelated), I frankly would not trust the ER opinion and would seek a neurological consultation soon (within a few days at the latest). A stroke can potentially cause isolated or almost isolated facial weakness, and can be easily confused with a Bells palsy by a physician not adequately trained in neurology. I am a little worried.
The key lies in getting a good neurological opinion, not in "tests". The latter are good supplements to a neurological history and examination, not a substitute.