Occult cerebral vascular causes of pseudotumor cerebri

Purpose: To underscore the deficiencies of standard computed imaging studie s for detecting occult cerebral Vascular conditions that can cause pseudotu mor cerebri. Methods: Two females with normal, unenhanced computed tomograp hy (CT) scans of the brain were initially thought to have pseudotumor cereb ri. Both patients experienced a progressive clinical course. Further imagin g revealed a torcular meningioma in case one, that was documented on enhanc ed magnetic resonance (MR) scan. The second case had a dural arteriovenous malformation identified on cerebral angiography. Conclusion: A normal nonco ntrast CT scan is insufficient to rule out partial obstruction of the dural sinuses by a meningioma or dural arteriovenous malformations that may incr ease the pressure within the dural sinuses. Thus, contrast CT or MR imaging and in some cases cerebral arteriography may be required in cases that man ifest atypical clinical features.