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Effects of fluid-percussion brain injury on regional cerebral blood flow and pial arteriolar diameter

Douglas S. DeWitt, Larry W. Jenkins, Enoch P. Wei, Harry Lutz, Donald P. Becker, and Hermes A. Kontos

E xperimental studies of fluid-percussion brain injury have demonstrated the occurrence of changes in cerebral blood flow (CBF) and the presence of impairment of normal vascular responses to changes in PaCO 2 , 44, 52 in PaO 2 , 36 and in systemic arterial pressure. 35 Similarly, abnormal cerebrovascular reactivity, often regional in nature, has been reported following head trauma in humans. 3, 9, 11, 13, 32, 45 Previous studies of the effects of fluid-percussion injury on the cerebral circulation have been carried out using direct observation of surface

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Large vascular malformation in a child presenting with vascular steal phenomenon managed with pial synangiosis

Case report

Michael J. Ellis, Derek Armstrong, and Peter B. Dirks

cerebral blood flow and cerebrovascular reactivity in moyamoya disease. 14 , 23 , 28 , 36 , 45 Patients who present with hemorrhage or recurrent ischemic events in the presence of impaired cerebrovascular reactivity are often considered for surgical treatment. 38 Direct and indirect revascularization techniques have been described, all with the common goal of enhancing blood flow to the hypoperfused brain. 34 While adults are often treated with direct superficial temporal–MCA bypass, this is often challenging or unfeasible in children, in which case indirect

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Indocyanine green videoangiography for recipient vessel stratification in superficial temporal artery–middle cerebral artery bypass surgery

Johannes Goldberg, Peter Vajkoczy, and Nils Hecht

procedure for flow augmentation of cerebral hemodynamic impairment between 2010 and 2019 and in whom pre- and postanastomosis ICG-VA images were available. In general, criteria for revascularization were 1) moyamoya vasculopathy (MMV) or stenoocclusive arteriosclerotic cerebrovascular disease (ACVD), 2) recurrent transient ischemic attacks under the best medical management, and 3) impaired cerebrovascular reactivity confirmed by PET or SPECT during acetazolamide challenge. Bypass patency at follow-up (12–18 months) was categorized according to the degree of MCA territory

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Evaluation of the transient hyperemic response test in head-injured patients

Piotr Smielewski, Marek Czosnyka, Peter Kirkpatrick, and John D. Pickard

H ead-injured patients who show depleted cerebrovascular reactivity during the first days after cerebral injury 5, 11, 25, 28 are more likely to have a worse outcome than those with intact reactivity. Defective autoregulation may explain why relatively mild secondary insults have such a profound effect on outcome. 20, 27, 30 The bedside real-time assessment of cerebral autoregulation is, therefore, of prognostic importance. To date, the most encouraging methods use noninvasive transcranial Doppler (TCD) ultrasonography to assess the relationship between

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EC-IC Bypass in Hemodynamic Cerebrovascular Disease

tomography lucencies in the caudate and perisylvian region, which is suggestive of a nonhemodynamic event. Two other patients obviously had only poor-quality anastomoses. This is in contrast to our own more recent experience in which patients with severely impaired cerebrovascular reactivity, as indicated by 133 Xe-enhanced dynamic single-photon emission computerized tomography (D-SPECT) studies with the use of the Diamox (acetazolamide) test, usually showed excellent bypass function. In view of these shortcomings, it is unfortunate that this report will probably be

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Defining thresholds for critical ischemia by using near-infrared spectroscopy in the adult brain

Peter J. Kirkpatrick, Joseph Lam, Pippa Al-Rawi, Piotr Smielewski, and Marek Czosnyka

, Firbank M , Delpy DT : The effect of overlying tissue on the spatial sensitivity profile of near-infrared spectroscopy. Phys Med Biol 40 : 2093 – 2108 , 1995 Okada E, Firbank M, Delpy DT: The effect of overlying tissue on the spatial sensitivity profile of near-infrared spectroscopy. Phys Med Biol 40: 2093–2108, 1995 20. Smielewski P , Czosnyka M , Pickard ID , et al : Clinical evaluation of near infrared spectroscopy for testing cerebrovascular reactivity in patients with carotid artery disease. Stroke

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Cerebral autoregulation following head injury

Marek Czosnyka, Piotr Smielewski, Stefan Piechnik, Luzius A. Steiner, and John D. Pickard

cerebrovascular spasm with transcranial Doppler ultrasound. J Neurosurg 60: 37–41, 1984 10.3171/jns.1984.60.1.0037 2. Aaslid R , Lindegaard KF , Sorteberg W , et al : Cerebral autoregulation dynamics in humans. Stroke 20 : 45 – 52 , 1989 Aaslid R, Lindegaard KF, Sorteberg W, et al: Cerebral autoregulation dynamics in humans. Stroke 20: 45–52, 1989 10.1161/01.STR.20.1.45 3. Bouma GJ , Muizelaar JP : Cerebral blood flow, cerebral blood volume, and cerebrovascular reactivity after severe head injury

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Thyrocervical trunk—external carotid artery bypass for positional cerebral ischemia due to common carotid artery occlusion

Technical note

Miguel A. Melgar, Deshdeepak Sahni, and Martin Weinand

normal baseline but also a persistently impaired cerebrovascular reactivity to acetazolamide. At 3 years posturgery MR angiography revealed anastomotic patency, and at the 5-year follow up no PCI spells were reported. Note that this patient remains neurologically intact and asymptomatic 5 years after the initial operation despite an unchanged postural decrease in his systolic pressure (20–30 mm Hg). Case 2 History and Examination This 76-year-old man presented to the neurology service with daily spells of confusion, left-handed clumsiness, blurred left

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Evaluation of the calcium channel antagonist nimodipine in experimental spinal cord ischemia

Alan I. Faden, Thomas P. Jacobs, and Michael T. Smith

AI, Jacobs TP, Smith GP, et al: Neuropeptides in spinal cord injury: comparative experimental models. Peptides 4: 631–634, 1983 10.1016/0196-9781(83)90009-8 8. Gelmers HJ : Effect of nimodipine (Bay e 9736) on post-ischaemic cerebrovascular reactivity, as revealed by measuring regional cerebral blood flow (rCBF). Acta Neurochir 63 : 283 – 290 , 1982 Gelmers HJ: Effect of nimodipine (Bay e 9736) on post-ischaemic cerebrovascular reactivity, as revealed by measuring regional cerebral blood flow (rCBF). Acta Neurochir 63: 283

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Ultrastructural evidence of arterial denervation following experimental subarachnoid hemorrhage

Thomas A. Duff, Grayson Scott, and John A. Feilbach

– 493 , 1984 Liszczak TM, Black PM, Tzouras A, et al: Morphological changes of the basilar artery, ventricles, and choroid plexus after experimental SAH. J Neurosurg 61: 486–493, 1984 10.3171/jns.1984.61.3.0486 13. Lobato RD , Marin J , Salaices M , et al : Cerebrovascular reactivity to noradrenaline and serotonin following experimental subarachnoid hemorrhage. J Neurosurg 53 : 480 – 485 , 1980 Lobato RD, Marin J, Salaices M, et al: Cerebrovascular reactivity to noradrenaline and serotonin following experimental