Neurosurgery
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Vascular endothelial growth factor (VEGF) is an important regulator of angiogenesis, the formation of which is triggered by hypoxia, cytokines, and growth factors and is also induced by activation of the adenosine 2B receptor. VEGF is neuroprotective in several models of experimental brain injury and is increased in brain after traumatic brain injury (TBI) in humans and experimental animals. Adenosine is a neuroprotective purine metabolite that increases in cerebrospinal fluid (CSF) after clinical TBI in children. We hypothesized that VEGF levels would 1). be increased in CSF after TBI in infants and children, and 2). be preceded by increases in CSF adenosine. To test this hypothesis, we designed a case-control study to compare the CSF of infants and children after severe TBI with that of uninjured children. ⋯ VEGF is increased in CSF after pediatric TBI, and this increase is associated with an increase in CSF adenosine. These results may imply that a component of the vascular regenerative response of the brain is initiated rapidly after TBI and continues for several days after injury. Further investigation is warranted to determine 1). whether this association is causative, 2). the role of adenosine in triggering the increase in CSF VEGF concentration, and 3). the exact role VEGF that plays after injury.
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To evaluate magnetic resonance imaging (MRI)- and microelectrode recording-guided cingulotomy for patients with psychiatric disorders and to develop a new method of mapping lesion location in anterior cingulate cortex that takes into account the significant interindividual variability in callosal morphometry. ⋯ Microelectrode recording is useful for lesion placement. Our system for reporting location in anterior cingulate cortex normalizes for differences in callosal morphometry. These techniques may aid future study.
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The pituicytoma is a rare primary tumor of the neurohypophysis. Although histologically benign, the location and vascular nature of these tumors can make surgical resection difficult. We present a report of two patients with pituicytomas and review the literature regarding treatment and prognosis for this unusual lesion. Possible histogenetic relationships of this tumor with other pituitary neoplasms are presented. ⋯ Pituicytomas are a distinct form of pituitary gland neoplasia that may recur if subtotally resected. These neurohypophysial tumors may contain a small subpopulation of previously unrecognized bcl-2-immunoreactive cells, whose role in the histogenesis of pituicytoma deserves further study.
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Comparative Study
Pretreatment and posttreatment evaluation of hemodynamic and metabolic parameters in intracranial dural arteriovenous fistulae with cortical venous reflux.
Retrograde drainage into the cortical veins results in poor outcome in patients with an intracranial dural arteriovenous fistula. However, the pathophysiological features of dural arteriovenous fistulae remain obscure. This study aimed to clarify hemodynamic and metabolic conditions in these patients using positron emission tomography. ⋯ The present results suggest that hemodynamic and metabolic characteristics vary widely among patients with cortical venous reflux. It is essential to precisely evaluate hemodynamic and metabolic conditions to predict their outcomes and therapeutic effects.
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To investigate the effects of mild hypothermia on brain microdialysate lactate after fluid percussion traumatic brain injury (TBI) in rats. ⋯ The cerebral extracellular fluid lactate level increases significantly after fluid percussion brain injury. Preinjury mild hypothermia completely inhibits the cerebral lactate accumulation, and early postinjury mild hypothermia significantly blunts the increase of cerebral lactate level after fluid percussion injury.