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Cerebral perfusion pressure

Takuma Ohmichi, Masaki Kondo, Masahiro Itsukage, Hidetaka Koizumi, Shigenori Matsushima, Nagato Kuriyama, Kazunari Ishii, Etsuro Mori, Kei Yamada, Toshiki Mizuno, Takahiko Tokuda
OBJECTIVE The gold standard for the diagnosis of idiopathic normal pressure hydrocephalus (iNPH) is the CSF removal test. For elderly patients, however, a less invasive diagnostic method is required. On MRI, high-convexity tightness was reported to be an important finding for the diagnosis of iNPH. On SPECT, patients with iNPH often show hyperperfusion of the high-convexity area. The authors tested 2 hypotheses regarding the SPECT finding: 1) it is relative hyperperfusion reflecting the increased gray matter density of the convexity, and 2) it is useful for the diagnosis of iNPH...
March 16, 2018: Journal of Neurosurgery
Vasilije Stambolija, Martina Miklić Bublić, Marin Lozić, Jakob Nemir, Miroslav Ščap
Background: Low brain tissue oxygen tension (PbtO2 ), or brain hypoxia, is an independent predictor of poor outcome. Increasing inspirational fraction of oxygen could have a significant influence on treating lower PbtO2 . Combined PbtO2 therapy, compared to the approach that focus only on regulation of cerebral perfusion pressure and intracranial pressure, shows better patient outcomes. Monitoring of PbtO2 could be helpful in individualizing treatment, preventing or limiting secondary brain injury, and maintaining better patient outcome...
2018: Surgical Neurology International
Dong Zhang, Pengcheng Xu, Hongyu Qiao, Xin Liu, Liangping Luo, Wenhua Huang, Heye Zhang, Changzheng Shi
BACKGROUND: Cerebrovascular events are frequently associated with hemodynamic disturbance caused by internal carotid artery (ICA) stenosis. It is challenging to determine the ischemia-related carotid stenosis during the intervention only using digital subtracted angiography (DSA). Inspired by the performance of well-established FFRct technique in hemodynamic assessment of significant coronary stenosis, we introduced a pressure-based carotid arterial functional assessment (CAFA) index generated from computational fluid dynamic (CFD) simulation in DSA data, and investigated its feasibility in the assessment of hemodynamic disturbance preliminarily using pressure-wired measurement and arterial spin labeling (ASL) MRI as references...
March 12, 2018: Biomedical Engineering Online
Ralph Rahme, Tejaswi D Sudhakar, Marjan Alimi, Timothy G White, Rafael A Ortiz, David J Langer
BACKGROUND AND IMPORTANCE: Cerebral hyperperfusion syndrome (CHS) is a well-known complication of superficial temporal artery (STA) to middle cerebral artery (MCA) bypass for ischemic cerebrovascular disease. While this argues against "low flow" in the bypass construct, flow rates in the graft have not been previously quantified in the setting of CHS. CLINICAL PRESENTATION: A 58-yr-old man presented with recurrent left hemispheric ischemic strokes and fluctuating right hemiparesis and aphasia...
March 3, 2018: Operative Neurosurgery (Hagerstown, Md.)
Iain D Croall, Daniel J Tozer, Barry Moynihan, Usman Khan, John T O'Brien, Robin G Morris, Victoria C Cambridge, Thomas R Barrick, Andrew M Blamire, Gary A Ford, Hugh S Markus
Importance: Blood pressure (BP) lowering is considered neuroprotective in patients with cerebral small vessel disease; however, more intensive regimens may increase cerebral hypoperfusion. This study examined the effect of standard vs intensive BP treatment on cerebral perfusion in patients with severe small vessel disease. Objective: To investigate whether standard vs intensive BP lowering over 3 months causes decreased cerebral perfusion in small vessel disease...
March 5, 2018: JAMA Neurology
Russell Knutsen, Scott C Beeman, Thomas J Broekelmann, Delong Liu, Kit Man Tsang, Attila Kovacs, Li Ye, Joshua Danback, Anderson Watson, Amanda Wardlaw, Jessica Wagenseil, Joel R Garbow, Michael Shoykhet, Beth A Kozel
Increased vascular stiffness correlates with higher risk of cardiovascular complications in aging adults. Elastin insufficiency, as observed in patients with Williams-Beuren syndrome or with familial supravalvular aortic stenosis, also increases vascular stiffness and leads to arterial narrowing. We used Eln+/- mice to test the hypothesis that pathologically increased vascular stiffness with concomitant arterial narrowing leads to decreased blood flow to end organs such as the brain. We also hypothesized that drugs which remodel arteries and increase lumen diameter would improve flow...
March 2, 2018: American Journal of Physiology. Heart and Circulatory Physiology
Meng Luen Lee, Ming Yuh Chang, Tung Ming Chang, Rei Cheng Yang, Ming Che Chang, Albert D Yang
Concurrent involvement of bilateral renal and cerebral arteries, usually incurred as stenosis, is rare in childhood-onset Takayasu arteritis (c-TA). We report the case of a 14-year-old girl, with c-TA, presenting with transient ischemic attack after endovascular revascularization for renal artery stenosis and cerebrovascular stroke after surgical revascularization for cerebral artery stenosis associated with childhood-onset moyamoya syndrome. We deem that decrease of blood pressure by endovascular revascularization and improvement of cerebral perfusion by surgical revascularization may have jeopardized the cerebral deep watershed zone to cerebral ischemia followed by cerebral hyperperfusion syndrome and caused transient ischemic attack and cerebrovascular stroke in our patient...
March 5, 2018: Journal of Korean Medical Science
Sophie Kelly, Steven M Bishop, Ari Ercole
OBJECTIVES: The pressure-reactivity index (PRx) is defined in terms of the moving correlation coefficient between intracranial pressure (ICP) and mean arterial pressure (MAP) and is a measure of cerebral autoregulation ability. Plots of PRx against cerebral perfusion pressure (CPP) show a U-shaped behaviour: the minimum reflecting optimal cerebral autoregulation (CPPopt). However U-shaped behaviour may also occur by chance. To date there has been no evaluation of the statistical properties of these signals...
2018: Acta Neurochirurgica. Supplement
Marine Flechet, Geert Meyfroidt, Ian Piper, Giuseppe Citerio, Iain Chambers, Patricia A Jones, Tsz-Yan Milly Lo, Per Enblad, Pelle Nilsson, Bart Feyen, Philippe Jorens, Andrew Maas, Martin U Schuhmann, Rob Donald, Laura Moss, Greet Van den Berghe, Bart Depreitere, Fabian Güiza
OBJECTIVE:   The aim of this study is to assess visually the impact of duration and intensity of cerebrovascular autoregulation insults on 6-month neurological outcome in severe traumatic brain injury. MATERIAL AND METHODS:   Retrospective analysis of prospectively collected minute-by-minute intracranial pressure (ICP) and mean arterial blood pressure data of 259 adult and 99 paediatric traumatic brain injury (TBI) patients from multiple European centres. The relationship of the 6-month Glasgow Outcome Scale with cerebrovascular autoregulation insults (defined as the low-frequency autoregulation index above a certain threshold during a certain time) was visualized in a colour-coded plot...
2018: Acta Neurochirurgica. Supplement
Konstantin Hockel, Martin U Schuhmann
OBJECTIVE: A drawback in the use of an external ventricular drain (EVD) originates in the fact that draining cerebrospinal fluid (CSF) (open system) and intracranial pressure (ICP) monitoring can be done at the same time but is considered to be unreliable regarding the ICP trace. Furthermore, with the more widespread use of autoregulation monitoring using blood pressure and ICP signals, the question arises of whether an ICP signal from an open EVD can be used for this purpose. Using an EVD system with an integrated parenchymal ICP probe we compared the different traces of an ICP signal and their derived parameters under opened and closed CSF drainage...
2018: Acta Neurochirurgica. Supplement
J Donnelly, M Czosnyka, H Adams, C Robba, L A Steiner, D Cardim, B Cabella, X Liu, A Ercole, P J Hutchinson, D K Menon, M J H Aries, P Smielewski
OBJECTIVES: Retrospective data from patients with severe traumatic brain injury (TBI) indicate that deviation from the continuously calculated pressure reactivity-based "optimal" cerebral perfusion pressure (CPPopt) is associated with worse patient outcome. The objective of this study was to assess the relationship between prospectively collected CPPopt data and patient outcome after TBI. METHODS: We prospectively collected intracranial pressure (ICP) monitoring data from 231 patients with severe TBI at Addenbrooke's Hospital, UK...
2018: Acta Neurochirurgica. Supplement
Bart Depreitere, Geert Meyfroidt, Fabian Güiza
INTRODUCTION: No consensus exists on the exact method for measuring mean arterial blood pressure (MAP) in the definition of cerebral perfusion pressure (CPP). The aim of the current study is to investigate how different MAP measurement methods have influenced the CPP recommendations in the Brain Trauma Foundation (BTF) guidelines. METHODS: All papers on which the chapter on CPP thresholds in the 2007 version of the BTF guidelines is based, were reviewed. If accurate descriptions of head of bed elevation and arterial pressure transducer height were lacking, the authors were emailed for clarification...
2018: Acta Neurochirurgica. Supplement
Murad Megjhani, Kalijah Terilli, Andrew Martin, Angela Velazquez, Jan Claassen, David Roh, Sachin Agarwal, Peter Smielewski, Amelia K Boehme, J Michael Schmidt, Soojin Park
OBJECTIVE: The objective was to explore the validity of industry-parameterized vital signs in the generation of pressure reactivity index (PRx) and optimal cerebral perfusion pressure (CPPopt) values. MATERIALS AND METHODS: Ten patients with intracranial pressure (ICP) monitors from 2008 to 2013 in a tertiary care hospital were included. Arterial blood pressure (ABP) and ICP were sampled at 240 Hz (of waveform data) and 0.2 Hz (of parameterized data produced by heuristic industry proprietary algorithms)...
2018: Acta Neurochirurgica. Supplement
M Cabeleira, M Czosnyka, X Liu, J Donnelly, P Smielewski
OBJECTIVES: Optimal cerebral perfusion pressure (CPPopt) is a concept that uses the pressure reactivity (PRx)-CPP relationship over a given period to find a value of CPP at which PRx shows best autoregulation. It has been proposed that this relationship be modelled by a U-shaped curve, where the minimum is interpreted as being the CPP value that corresponds to the strongest autoregulation. Owing to the nature of the calculation and the signals involved in it, the occurrence of CPPopt curves generated by non-physiological variations of intracranial pressure (ICP) and arterial blood pressure (ABP), termed here "false positives", is possible...
2018: Acta Neurochirurgica. Supplement
Peter Smielewski, Luzius Steiner, Corina Puppo, Karol Budohoski, Georgios V Varsos, Marek Czosnyka
OBJECTIVE: Brain arterial critical closing pressure (CrCP) has been studied in several diseases such as traumatic brain injury (TBI), subarachnoid haemorrhage, hydrocephalus, and in various physiological scenarios: intracranial hypertension, decreased cerebral perfusion pressure, hypercapnia, etc. Little or nothing so far has been demonstrated to characterise change in CrCP during mild hypocapnia. METHOD: We retrospectively analysed recordings of intracranial pressure (ICP), arterial blood pressure (ABP) and blood flow velocity from 27 severe TBI patients (mean 39...
2018: Acta Neurochirurgica. Supplement
Katarzyna Kaczmarska, Magdalena Kasprowicz, Antoni Grzanka, Wojciech Zabołotny, Peter Smielewski, Despina Afroditi Lalou, Georgios Varsos, Marek Czosnyka, Zofia Czosnyka
OBJECTIVES: The objectives were to compare three methods of estimating critical closing pressure (CrCP) in a scenario of a controlled increase in intracranial pressure (ICP) induced during an infusion test in patients with suspected normal pressure hydrocephalus (NPH). METHODS: We retrospectively analyzed data from 37 NPH patients who underwent infusion tests. Computer recordings of directly measured intracranial pressure (ICP), arterial blood pressure (ABP) and transcranial Doppler cerebral blood flow velocity (CBFV) were used...
2018: Acta Neurochirurgica. Supplement
M Moreira, D Fernandes, E Pereira, E Monteiro, R Pascoa, C Dias
OBJECTIVE: Severe traumatic brain injury (TBI) management has been associated with adult respiratory distress syndrome (ARDS) in previous literature. We aimed to investigate the relationships between optimal CPP-guided management, ventilation parameters over time and outcome after severe TBI. MATERIALS AND METHODS: We performed retrospective analysis of recorded data from 38 patients admitted to the NCCU after severe TBI, managed with optimal cerebral perfusion pressure (CPPopt)-guided therapy, calculated using pressure reactivity index (PRx)...
2018: Acta Neurochirurgica. Supplement
Ari Ercole, Peter Smielewski, Marcel J H Aries, Robin Wesselink, Jan Willem J Elting, Joseph Donnelly, Marek Czosnyka, Natasha M Maurits
OBJECTIVE: An 'optimal' cerebral perfusion pressure (CPPopt) can be defined as the point on the CPP scale corresponding to the greatest autoregulatory capacity. This can be established by examining the pressure reactivity index PRx-CPP relationship, which is approximately U-shaped but suffers from noise and missing data. In this paper, we present a method for plotting the whole PRx-CPP relationship curve against time in the form of a colour-coded map depicting the 'landscape' of that relationship extending back for several hours and to display this robustly at the bedside...
2018: Acta Neurochirurgica. Supplement
Joseph Donnelly, Marek Czosnyka, Spencer Harland, Georgios V Varsos, Danilo Cardim, Chiara Robba, Xiuyun Liu, Philip N Ainslie, Peter Smielewski
OBJECTIVES: Increased intracranial pressure (ICP) is a pathological feature of many neurological diseases; however, the local and systemic sequelae of raised ICP are incompletely understood. Using an experimental paradigm, we aimed to describe the cerebrovascular consequences of acute increases in ICP. MATERIALS AND METHODS: We assessed cerebral haemodynamics [mean arterial blood pressure (MAP), ICP, laser Doppler flowmetry (LDF), basilar artery Doppler flow velocity (Fv) and estimated vascular wall tension (WT)] in 27 basilar artery-dependent rabbits during experimental (artificial lumbar CSF infusion) intracranial hypertension...
2018: Acta Neurochirurgica. Supplement
T Lo, I Piper, B Depreitere, G Meyfroidt, M Poca, J Sahuquillo, T Durduran, P Enblad, P Nilsson, A Ragauskas, K Kiening, K Morris, R Agbeko, R Levin, J Weitz, C Park, P Davis
OBJECTIVES: Validated optimal cerebral perfusion pressure (CPP) treatment thresholds in children do not exist. To improve the intensive care unit (ICU) management of the paediatric traumatic brain injury (TBI) population, we are forming a new paediatric multi-centre collaboration to recruit standardised ICU data for running and reporting upon models for assessing autoregulation and optimal CCP (CPPopt). MATERIALS AND METHODS: We are adapting the adult BrainIT group's approach to develop a new Paediatric Brain Monitoring and Information Technology Group (KidsBrainIT), which will include a repository to store prospectively collected high-resolution physiological, clinical, and outcome data...
2018: Acta Neurochirurgica. Supplement
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