Cerebral hemodynamics and metabolism in pseudotumor cerebri.

A comprehensive analysis of cerebral hemodynamics and metabolism was carried out in 14 patients with pseudotumor cerebri. Tracer techniques were employed to measure cerebral blood flow (CBF) and vascular reactivity to acute changes in arterial carbon dioxide tension and blood pressure, cerebral blood volume (CBV), and the cerebral metabolic rate for oxygen and glucose. There was a small reduction (p less than 0.01) in CBF (44 +/- 7 ml/100 gm/min; normal, 54 +/- 9) with normal vascular reactivity; an increase (p less than 0.005) in CBV (4.8 +/- 0.8 ml/100 gm; normal, 3.6 +/- 0.5), and normal cerebral metabolism. We conclude that an abnormality of the cerebral microvasculature is responsible for an elevation in CBV, but the intracranial hypertension can be explained only by tissue swelling due to an increase in water content. The relationship between the vascular abnormality and the tissue swelling remains to be defined.