Cerebral blood flow regulation under activation of the primary somatosensory cortex during electrical stimulation of the forearm.

Coupling of neuronal activity to cerebral blood flow (CBF) is widely accepted, but the exact mechanism is still under investigation. We assessed the responses of CBF coupled with electrical activity over the primary somatosensory cortex (S-I) during electrical stimulation of the contralateral forearm in cats. CBF in S-I was monitored using laser-Doppler flowmetry (LDF), and electrical activity was recorded with a tungsten microelectrode.

Neural activation of the brain with hemodynamic insufficiency.

Little is known about how ischemia affects hemodynamic responses to neural activation in the brain. We compare the effects of a motor activation task and a cerebral vasodilating agent, acetazolamide (ACZ), on regional cerebral blood flow (rCBF) in primary sensorimotor cortex (PSM) in six patients with major cerebral artery steno-occlusive lesions without paresis of the upper extremities. Quantitative rCBF was measured in all patients using H2(15)O autoradiographic method and positron emission tomography.

[A case of hemangiopericytoma with multiple extracranial metastasis: a case report].

A case of a patient with hemangiopericytoma with multiple extracranial metastasis, who has survived for more than twenty years is reported. A fifty-five-year-old male presented brain tumor twenty years ago. He underwent total removal of the tumors, but recurrences occurred each time.

Human dural thickness measured by ultrasonographic method: reflection of intracranial pressure.

We measured changes in dural thickness to estimate intracranial pressure. The dural thickness on magnetic resonance imaging with contrast enhancement was compared in a hydrocephalic patient before and after shunt operation. Dural thickness also was measured directly using a micrometer at craniotomy for aneurysmal clipping in 11 patients.

Comparison of vasodilatory effect of carbon dioxide inhalation and intravenous acetazolamide on brain vasculature using positron emission tomography.

Carbon dioxide (CO2) and acetazolamide are increasingly being used as vasodilators to detect cerebrovascular reserve capacity in patients of chronic cerebrovascular disease. The functional cerebrovascular reserve or ability of cerebral vessels to lower their resistance in response to decrease in cerebral perfusion pressure is expressed as change in cerebral blood flow from baseline under a vasodilatory stimuli. Theoretically a vasodilator causing maximum vasodilation, and thereby expressing complete reserve capacity would be more suitable for such a purpose.