[MRI findings of brain-stem tuberculoma in a case of tuberculous meningitis].

A 54-year-old woman developed headache and slight fever. When she consulted a physician, she could not move either of her eyes to the right. Cranial CT scan revealed no significant findings. Lumbar puncture was performed and CSF examination showed the cell count of 10,304/mm3, glucose level of 10 mg/dl, and total protein value of 270 mg/dl. Her symptoms and laboratory findings suggested meningitis and she was admitted to our hospital. Neurological examination revealed bilateral dilated pupils with sluggish light reflex, right gaze palsy, and hypesthesia of the left side of her face. A diagnosis of tuberculous meningitis was established by a positive test for acid-fast bacillus in CSF, and anti-tuberculous therapy was started at once. One month after the onset of symptoms, her main complaints were double vision and cerebellar ataxia. Both CT and MRI revealed a right brain-stem lesion. Pre-contrast CT could not clearly visualize the lesion but with contrast medium a homogeneously-enhanced circular lesion was shown. MRI on T2WI demonstrated the right brain-stem lesion to have a central bright core with hypointense periphery, which in turn was surrounded by hyperintensity. The lesion appeared isointense with cerebral white matter and the "central bright core" area was demonstrated to be slightly hypointense on T1WI. On post-contrast T1WI (with Gd-DTPA), the lesion showed strong homogeneous enhancement. The CT and MRI findings indicated a brain-stem tuberculoma, which was regarded as the cause of the ocular movement paralysis and cerebellar ataxia. As the clinical symptoms gradually resolved with anti-tuberculous treatment, the MRI appearance of the lesion also improved.(ABSTRACT TRUNCATED AT 250 WORDS)