Table 1.

Modified Dandy Criteria (16).

1. Signs and symptoms of increased intracranial pressure (headaches, nausea, vomiting, transient obscurations of vision, papilledema). 2. No localizing neurologic signs otherwise, with the single exception being unilateral or bilateral VI nerve paresis. 3. CSF can show increased pressure, but no cytologic, or chemical abnormalities otherwise. 4. Normal to small symmetric ventricles must be demonstrated (originally required ventriculography, but now demonstrated by CT).