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H. Richard Winn

evident in both the adult and pediatric populations, whereas altered immune status, due to the presence of HIV or treatment with chemotherapy, has resulted in the upsurge of previously infrequent causes of these lesions. This changing nature of the disease presents a therapeutic challenge to neurosurgeons irrespective of their practice location. In this volume of Neurosurgical Focus , topics range from routine disorders to the philosophical and pathophysiological basis of brain infection. These articles should provide to the reader a better understanding of the present

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Matthew A. Howard III, Ralph G. Dacey Jr. and H. Richard Winn

test tube was filled to a final calculated volume of 10 µ l/block. The tissue was disrupted into a fine cell suspension by gentle pipetting with a sterile fire-polished Pasteur pipette. The suspension was then drawn into a Hamilton syringe and transplanted stereotaxically into a pair of recipient rats. A 10- µ l sample of the suspension was drawn up for each pair of transplant recipients. One of each pair of rats received the first 5- µ l aliquot and the other received the second 5- µ l aliquot from the same syringe. In this way both rats in each pair were injected

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Matthew A. Howard III, Alan S. Gross, Ralph G. Dacey Jr. and H. Richard Winn

treatment. “Functional survival” is defined as a GOS grade of good or moderately disabled. TABLE 2 Time from head injury to emergency room admission Time Interval Older Group Younger Group < 1 hr 15 11 1 to < 3 hrs 3 8 3 to 6 hrs 2 1 > 6 hrs 8 6 unknown 6 7 total cases 34 33 Fifty-two admission CT scans (22 in the young group and 30 in the old group) were available for analysis of acute SDH volume, size of midline shift, and presence or absence of intracerebral

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Hisato Higashi, Joseph R. Meno, Amitoj S. Marwaha and H. Richard Winn

seven experimental groups: normoglycemic animals treated with saline, theophylline, or ZM 241385 and hyperglycemic animals treated with saline, theophylline, or ZM 241385. A seventh group, the sham injury group (six animals), received identical surgical manipulations but was not subjected to ischemia. Thirty minutes before the onset of ischemia, animals received intraperitoneal injections of theophylline (36 mg/kg), ZM 241385 (1 mg/kg), or an equivalent volume of saline. The hyperglycemic groups were given an intraperitoneal injection of 17% d -glucose (3 g/kg) 15

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David D. Weaver, H. Richard Winn and John A. Jane

marked in the hemisphere associated with the lesion except when ICP's were higher than 44 mm Hg. At this point, increased ICP induced a reduction of cerebral blood flow. Finally, the relationship between ICP and elasticity of the central nervous system should be mentioned. Early studies by Flexner, et al. , 3 demonstrated the elastic properties of the central nervous system and indeed showed differences in the coefficient of elasticity of dogs, dependent on their age. More recent experiments clearly relate pressure as a logarithmic function of intracranial volume

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Robert F. Bedford, Ralph Dacey, H. Richard Winn and Carl Lynch III

. Intracranial pressure-volume relationship was measured from the increase in ICP caused by a 1-ml bolus injection of mock cerebrospinal fluid through the subarachnoid bolt. After control measurements of cardiovascular variables and ICP were obtained, general anesthesia was induced with thiopental (3 mg/kg intravenously), nitrous oxide (70% in O 2 ), and pancuronium (0.1 mg/kg intravenously). Ventilation was controlled by face mask to maintain a constant end-tidal CO 2 fraction. In five patients chosen randomly by lot, verapamil (5 mg) was given as an intravenous bolus to

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Michelle J. Smith, Peter D. Le Roux, J. Paul Elliott and H. Richard Winn

CT scanning at admission, after aneurysm occlusion, and at least once subsequently during their hospital stay. Single-photon emission computerized tomography scans and four-vessel angiograms were obtained during the period of maximum vasospasm risk in the majority of patients; these individuals were cared for in the neurosurgery ICU with the aid of intracranial pressure and invasive hemodynamic monitoring. Volume expansion and hemodilution (normal saline infusion and albumin boluses) were initiated prophylactically in all patients. Also, each patient received

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Arthur M. Lam, H. Richard Winn, Bruce F. Cullen and Nancy Sundling

the most severe injury (a GCS score ≤ 8), we sought to minimize the potential bias inherent in a retrospective study. The nature of the intravenous infusion was not controlled, but all patients received a 5% dextrose and 0.2% saline infusion as maintenance fluid in the intensive care unit and lactated Ringer's solution or normal saline for replenishment of intravascular volume. The more severely injured patients did not receive additional glucose-containing solutions. We studied data obtained after the 10-day outcome instead of the conventional 6-month outcome

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Varun Laohaprasit, Daniel L. Silbergeld, George A. Ojemann, Joseph M. Eskridge and H. Richard Winn

RG : Regional blood flow and blood-to-tissue transport in five brain tumor models. Prog Exp Tumor Res 27 : 132 – 153 , 1984 Groothuis DR, Molnar P, Blasberg RG: Regional blood flow and blood-to-tissue transport in five brain tumor models. Prog Exp Tumor Res 27: 132–153, 1984 11. Hatam A , Bergström M , Yu ZY , et al : Effect of dexamethasone treatment in volume and contrast enhancement of intracranial neoplasms. J Comput Assist Tomogr 7 : 295 – 300 , 1983 Hatam A, Bergström M, Yu ZY, et al

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H. Richard Winn, Michael Mendes, Paul Moore, Clarabelle Wheeler and George Rodeheaver

disadvantages of requiring multiple stages of surgical preparation, 13 injection of foreign material with the bacteria, 16, 17, 20, 21 or the use of large animals. 20, 28 Models employing a contaminated embolus are problematic, and mortality due to accompanying brain infarction is quite high even in control groups. 21, 28 With our model, brain abscess was consistently achieved in one step, at a specific site and with the injection of only bacteria. The inoculum can be regulated both in volume and the number of bacteria. Unlike previous models, 21 the number of bacteria