Definite disease:

All the three are required:

1. Positive ISG^* for Bechet's Disease.

2. Neurologic syndrome (with objective signs present) known as produced by Bechet disease with typical MRI or CSF findings.

3. No alternative explanation for the neurological findings.

Probable disease:

1. At least one of these in absence of other better explanation for neurological findings.

2. Neurologic syndrome characteristic (like in the paragraph "definite") and systemic features of BD, but not satisfying ISG criteria.

3. Neurologic syndrome non-characteristic in the context of BD supported by ISG criteria.