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Christopher Reilly, Chris Amidei, Jocelyn Tolentino, Babak S. Jahromi and R. Loch Macdonald

investigated the role of these factors in relation to vasospasm, there are no studies in which the relationships between vasospasm and initial clot volume, clearance, and density have been examined simultaneously and quantitatively. Because larger volumes of clot might clear more slowly, a multivariate analysis would be needed to determine whether clot volume and clearance are independent factors associated with vasospasm. Clinical Material and Methods Patient Characteristics and Clinical Variables After approval of the protocol by the Institutional Review Board

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Anthony Wan, Blessing N. R. Jaja, Tom A. Schweizer and R. Loch Macdonald

vasospasm. The trials failed to show the efficacy of the treatment agent, thereby allowing for the pooling of both trial arms in this analysis. Baseline Characteristics In C-1, the volume of ICH was measured as xyz/2 where x, y, and z are the 3 maximum orthogonal diameters of a clot. Midline shift was measured in millimeters. In the SHOP and tirilazad data, ICH was recorded as present or absent. In the pooled data, ICH was categorized qualitatively as either present or absent. The considered baseline characteristics included age, sex, ethnicity, hypertension, angina

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R. Loch Macdonald

, thrombosis (perhaps the microthromboemboli we discuss today), or angiographic vasospasm. Even at that time, published data presented conflicting opinions about the importance of angiographic vasospasm as a cause of symptoms, or what may now be called delayed cerebral ischemia (DCI). 17 Patients with SAH were thought to frequently be hypovolemic. Maroon and Nelson 10 were among the first to actually show this. The treatment protocol of Kosnik and Hunt was induced hypertension (IH) and volume expansion sufficient to permit the inotropes that were administered to raise the

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R. Loch Macdonald

chances of symptoms were less than 50%. The authors challenge opinions that the risk of hemorrhage from a CCM is higher during pregnancy 15 , 17 and conclude that, in fact, this risk is not increased during pregnancy. There is no necessity for cesarean section, and vaginal delivery seems safe. Why would the risk of hemorrhage be higher during pregnancy? Perhaps because of hemodynamic changes during pregnancy. Blood volume increases in pregnancy, peaks at 32 weeks, and remains elevated until delivery. 4 Hematocrit falls slightly and systemic vascular resistance

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Masataka Takahashi, Zhen-Du Zhang and R. Loch Macdonald

% buffered formalin or processed for water or Evans blue contents. Brain Water, Evans Blue and Histology Histological sections were cut, stained with H & E, and viewed under a light microscope by a blinded investigator. Sections from the anterior frontal, middle frontal, parietal, and occipital regions of the hemispheres were used to measure Evans blue content. They were divided into right and left hemispheres, and each section was blotted and weighed. They were homogenized in 5 ml 50% trichloroacetic acid (weight/volume) and centrifuged at 2000 G for 25 minutes

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R. Loch Macdonald

correlations (frequency of craniotomy in relation to residency program, hospital volume, and for/not for profit) without knowing more about the indications for surgery. Arguments can be made for these factors increasing or decreasing the use of surgery. Higher rates of surgery at for-profit hospitals have been reported before, and the financial incentive is one possible explanation. 1 High-volume centers are more likely to have neurosurgical residency programs and to follow guidelines. 3 , 8 There are a lot of subdural hematomas, and the International Classification of

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Nir Lipsman, Jocelyn Tolentino and R. Loch Macdonald

T he prognosis for patients with aneurysmal SAH can be affected by the patient's preexisting health state, the characteristics of the pathological entity, such as aneurysm features and hemorrhage severity, and finally to various aspects of treatment. 21 , 23 , 28 Some factors associated with poor outcome include increasing age, severe initial neurological grade, the presence of a posterior circulation aneurysm, larger aneurysms, a larger volume of subarachnoid blood on initial CT scan, intracerebral hematoma or intraventricular hemorrhage, elevated

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Daipayan Guha, George M. Ibrahim, Joshua D. Kertzer and R. Loch Macdonald

remain the strongest predictors of outcome following SAH, interregional and cross-national disparities may also contribute to heterogeneities in patient outcomes. 31 Such differences may be related to the expertise of the treating physician and the volume of SAH encountered within the institution, 2 or may be secondary to discrepancies in treatment protocols for common SAH complications, including hydrocephalus and vasospasm. 6 It is also increasingly recognized that socioeconomic factors may be linked to patient outcomes following SAH. 20 In this study, we

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J. Max Findlay, R. Loch Macdonald, Bryce K. A. Weir and Michael G. A. Grace

18. Kassell NF , Peerless SJ , Durward QJ , et al : Treatment of ischemic deficits from vasospasm with intravascular volume expansion and induced arterial hypertension. Neurosurgery 11 : 337 – 343 , 1982 Kassell NF, Peerless SJ, Durward QJ, et al: Treatment of ischemic deficits from vasospasm with intravascular volume expansion and induced arterial hypertension. Neurosurgery 11: 337–343, 1982 19. Kassell NF , Torner JC , Jane JA , et al : The International Cooperative Study on the Timing

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Bozena A. M. Vollrath, Bryce K. A. Weir, R. Loch Macdonald and David A. Cook

5% CO 2 . After the explants had adhered, the volume of the medium was made up gradually over the next 4 days to 4 ml per flask, and thereafter the culture medium was changed weekly. When the primary cultures were almost confluent, the cells were transferred to 75-sq cm flasks and then routinely subcultured at a split ratio of 1:3. Smooth-muscle cells showed the characteristic “hills and valleys” pattern of growth, and cells from four to 10 passages were used in the experiments. Binding Assay for Inositol Triphosphate The cellular content of IP 3 was