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Novel index for predicting mortality during the first 24 hours after traumatic brain injury

Hakseung Kim, Hack-Jin Lee, Young-Tak Kim, Yunsik Son, Peter Smielewski, Marek Czosnyka, and Dong-Joo Kim

study, we speculated that the extent of hypoperfusion would be reflected by a specifically designed parameter that incorporates the combined status of hypotension, intracranial hypertension, and cerebrovascular reactivity. In addition, this study tested the prognostic capacity of this parameter during the first 24 hours of ICP monitoring. Methods This study investigated the association between the duration of cerebral hypoperfusion and mortality in TBI patients during the first 24 hours of neurocritical care unit (NCCU) admission. Cerebral hypoperfusion events were

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The effects of graded experimental trauma on cerebral blood flow and responsiveness to CO2

Myles L. Saunders, J. Douglas Miller, Donald Stablein, and Gilbert Allen

I mpairment of cerebral vasomotor responsiveness to changes in partial pressure of arterial carbon dioxide (PaCO 2 ) has been observed in man after accidental head injuries, 7–9, 28, 29, 33, 39, 40 and in laboratory animals following experimentally induced cerebral trauma. 20, 34, 42 Often, however, the primary traumatic lesions in these experimental models, and certainly in patients, have been contaminated by secondary insults such as hypoxemia, ischemia, and hypertension or hypotension, which have, themselves, been shown to alter cerebrovascular reactivity

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Cerebrovascular reactivity to noradrenaline and serotonin following experimental subarachnoid hemorrhage

Ramiro D. Lobato, Jesús Marín, Mercedes Salaices, Fernando Rivilla, and Javier Burgos

✓ This study analyzes the time course of the changes induced by subarachnoid hemorrhage (SAH) in the sensitivity of cat cerebral arteries to noradrenaline and serotonin. Cerebral arteries displayed a supersensitivity to these amines, which was most marked 3 days after the experiment and then gradually disappeared. The supersensitivity to serotonin was greater and longer than the response to noradrenaline. The increased in the vascular contractile response induced by SAH was similar to that seen after superior cervical ganglionectomy or intracisternal injections of 6-hydroxydopamine. It is suggested that supersensitivity to noradrenaline and serotonin induced by SAH may be involved in the production of chronic cerebral vasospasm.

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Prior Infarcts, Reactivity, and Angiography in Moyamoya Disease (PIRAMD): a scoring system for moyamoya severity based on multimodal hemodynamic imaging

Travis R. Ladner, Manus J. Donahue, Daniel F. Arteaga, Carlos C. Faraco, Brent A. Roach, L. Taylor Davis, Lori C. Jordan, Michael T. Froehler, and Megan K. Strother

studies based on PET or SPECT. Studies of hemodynamic reserves are probably a useful adjunct; however, current clinical methods require exogenous contrast administration and/or ionizing radiation. Although such tools have improved our understanding of moyamoya, these methods are suboptimal for longitudinal monitoring of patients or assessing revascularization response, because of dose restrictions. Cerebrovascular reactivity (CVR) is a well-documented and valuable surrogate marker of cerebrovascular reserve in patients with previously identified intravascular

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Transcranial Doppler ultrasound studies of cerebral autoregulation and subarachnoid hemorrhage in the rabbit

Richard J. Nelson, Sheila Perry, Tony K. Hames, and John D. Pickard

reactivity has already been employed in studies of extracranial vascular disease. 56, 65 To use TCD in the place of existing methods of measuring cerebrovascular reactivity assumes that the caliber and flow velocity profiles of the basal cerebral arteries are not significantly altered by changes in PaCO 2 and that changes in mean flow velocity accurately reflect changes in regional CBF. The development of delayed cerebral ischemia after subarachnoid hemorrhage (SAH) is strongly related to the loss of normal cerebral autoregulation 19, 42, 44, 54 and reactivity 62 and

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Severely impaired cerebrovascular reserve in patients with cerebral proliferative angiopathy

Clinical article

Jorn Fierstra, Stephanie Spieth, Leanne Tran, John Conklin, Michael Tymianski, Karel G. ter Brugge, Joseph A. Fisher, David J. Mikulis, and Timo Krings

. Structural axial MR imaging and angiographic images in anterior-to-posterior and lateral orientations are shown for 3 of the lesions (left 3 columns) , whereas Gd-enhanced T1-weighted MR imaging acquisitions illustrate the CPA lesion for Case 4 (far right column) in the 3 planes (A) . The CPA lesion for Case 4 was diagnosed angiographically in another hospital; therefore, an angiographic examination from our institution was not indicated. Panel B shows the functional CVR overlay for each case. Cerebrovascular reactivity is calculated as the percentage change in BOLD

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Flow augmentation STA-MCA bypass evaluation for patients with acute stroke and unilateral large vessel occlusion: a proposal for an urgent bypass flowchart

Martina Sebök, Giuseppe Esposito, Christiaan Hendrik Bas van Niftrik, Jorn Fierstra, Tilman Schubert, Susanne Wegener, Jeremia Held, Zsolt Kulcsár, Andreas R. Luft, and Luca Regli

found only 16 level IV studies and 3 level III studies. This lack of evidence encouraged further research to explore the use of flow augmentation bypass in the management of acute ischemic stroke. A major challenge is adequate identification of patients with persistent hypoperfusion and insufficient collateral flow in the setting of acute stroke who will benefit from microsurgical revascularization. 13 In this regard, blood oxygenation level–dependent functional MRI (BOLD fMRI) of cerebrovascular reactivity (CVR) is known as an efficient tool for studying cerebral

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Contemporary and emerging magnetic resonance imaging methods for evaluation of moyamoya disease

Vance T. Lehman, Petrice M. Cogswell, Lorenzo Rinaldo, Waleed Brinjikji, John Huston III, James P. Klaas, and Giuseppe Lanzino

the assessment of MMD has been extensively investigated. 21 , 22 , 28 , 43 , 48 , 63 The “ivy sign,” an indicator of slow or retrograde flow in cortical vessels, can help characterize the origins of collateral supply, correlates with cerebrovascular reactivity (CVR), and can improve in response to revascularization surgery, or it can temporarily worsen after revascularization in the setting of hyperperfusion. 21 , 28 , 48 In the cerebral white matter, linear T2 hyperintense streaks perpendicular to the lateral ventricle, referred to as “medullary streaks,” have

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Effect of decompressive craniectomy on intracranial pressure and cerebrospinal compensation following traumatic brain injury

Ivan Timofeev, Marek Czosnyka, Jurgens Nortje, Peter Smielewski, Peter Kirkpatrick, Arun Gupta, and Peter Hutchinson

cerebral compliance, and may represent even more substantial derangement in cerebrovascular reactivity. Another possible explanation for such pronounced change in pressure reactivity is the development of postdecompression hyperemia with associated vasoparesis or a cerebral equivalent of “reperfusion” syndrome, which have been described in other parts of the body when prolonged compression is relieved. Yamakami and Yamaura 33 reported a substantial increase in regional CBF in the decompressed brain regions. This hyperperfusion progressed for up to 1 week after

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Age-related carbon dioxide reactivity in children after moderate and severe traumatic brain injury

Tensing Maa, Keith Owen Yeates, Melissa Moore-Clingenpeel, and Nicole F. O'Brien

neurological outcomes after severe TBI over the past 2 decades. 25 Among the pediatric age group, there is a difference in outcome with increasing age. 3 , 7 , 15 , 16 In particular, children younger than 2 years may have worse outcomes than older children. 1 , 2 A greater understanding of the pathophysiological changes that occur in the pediatric brain following moderate and severe TBI is needed to identify alternative, additional, or individualized treatment approaches that may benefit these children. Cerebrovascular reactivity (CVR) reflects the normal response of