Clin Physiol Funct Imaging
January 2025
Background: Antihypertensives (AHD) can influence cerebral autoregulation (CA) and attenuate hypertrophic concentric remodelling of arterioles. The aim of this study was to examine the associations between AHD, CA and structural and functional properties of cerebral arteries.
Methods: In this observational, cross-sectional study 115 volunteers were divided in group 1 (non-hypertensive) [n = 30]; group 2 (hypertensive with systolic blood pressure [SBP] < 140 and diastolic blood pressure [DBP] < 90 mmHg) [n = 54]; group 3 (hypertensive with SBP ≥ 140 or DBP ≥ 90 mmHg) [n = 31] and simultaneous measurements of systemic blood pressure (BP) and middle cerebral artery blood flow velocity (CBFV) were obtained from digital plethysmography and transcranial Doppler.
J Hum Hypertens
January 2025
Antihypertensive treatment (AT) is essential for preventing hypertension-related cognitive decline. The goals of this observational study were to compare cognitive performance (CP) between non-hypertensive (NH) volunteers and hypertensive patients and to evaluate the correlation between CP and antihypertensive drugs (AHD). Three groups were constituted: NH (n = 30) [group 1], hypertensive with systolic blood pressure (SBP) < 140 mmHg and diastolic blood pressure (DBP) < 90 mmHg (n = 54) [group 2] and hypertensive with SBP ≥ 140 or DBP ≥ 90 (n = 31) [group 3].
View Article and Find Full Text PDFPerfusion Computed Tomography (PCT) is an alternative tool to assess cerebral hemodynamics during trauma. As acute traumatic subdural hematomas (ASH) is a severe primary injury associated with poor outcomes, the aim of this study was to evaluate the cerebral hemodynamics in this context. Five adult patients with moderate and severe traumatic brain injury (TBI) and ASH were included.
View Article and Find Full Text PDFCereb Circ Cogn Behav
November 2023
Arq Neuropsiquiatr
November 2023
Background: Coronavirus disease 2019 (COVID-19) has emerged as a public health emergency worldwide, predominantly affecting the respiratory tract. However, evidence supports the involvement of extrapulmonary sites, including reports of intracranial hemorrhages.
Objective: To describe six original cases and review the literature on intracranial hemorrhages in patients diagnosed with COVID-19 by molecular methods.
Introduction And Objectives: Acute liver failure, also known as fulminant hepatic failure (FHF), includes a spectrum of clinical entities characterized by acute liver injury, severe hepatocellular dysfunction and hepatic encephalopathy. The objective of this study was to assess cerebral autoregulation (CA) in 25 patients (19 female) with FHF and to follow up with seventeen of these patients before and after liver transplantation.
Patients And Methods: The mean age was 33.
Respir Physiol Neurobiol
January 2024
Cerebrovascular responses were compared between COPD and non-COPD participants. The association between COPD severity and cognitive function was also investigated. Cerebral blood velocity in the middle cerebral artery, blood pressure, and end-tidal CO were recorded at rest, followed by a brain activation paradigm, and an inhaled gas mixture (5% CO) to assess cerebral autoregulation (CA), neurovascular coupling (NVC) and cerebrovascular reactivity to carbon dioxide (CVR), respectively.
View Article and Find Full Text PDFJ Cereb Blood Flow Metab
November 2023
Background: The coronary calcium score (CAC) measured on chest computerized tomography is a risk marker of cardiac events and mortality. We compared CAC scores in two multiethnic groups without symptomatic coronary artery disease: subjects in the chronic phase after stroke or transient ischemic attack and at least one symptomatic stenosis ≥50% in the carotid or vertebrobasilar territories (Group) and a control group (Group).
Methods: In this cross-sectional study, Group included two subgroups: Group, with stenoses in either cervical intracranial arteries, and Group, with stenoses in at least one cervical and one intracranial artery.
Background: Critical closing pressure (CrCP) and resistance-area product (RAP) have been conceived as compasses to optimize cerebral perfusion pressure (CPP) and monitor cerebrovascular resistance, respectively. However, for patients with acute brain injury (ABI), the impact of intracranial pressure (ICP) variability on these variables is poorly understood. The present study evaluates the effects of a controlled ICP variation on CrCP and RAP among patients with ABI.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
February 2023
Cerebral perfusion pressure (CPP) is normally expressed by the difference between mean arterial blood pressure (MAP) and intracranial pressure (ICP) but comparison of the separate contributions of MAP and ICP to human cerebral blood flow autoregulation has not been reported. In patients with acute brain injury (ABI), internal jugular vein compression (IJVC) was performed for 60 s. Dynamic cerebral autoregulation (dCA) was assessed in recordings of middle cerebral artery blood velocity (MCAv, transcranial Doppler), and invasive measurements of MAP and ICP.
View Article and Find Full Text PDFClin Neurol Neurosurg
September 2022
Objectives: This study aimed to investigate the accuracy of TCS combined with the Sniffin' sticks olfactory test (SST-16) for differentiation between idiopathic PD patients and healthy controls compared to that of Tc-TRODAT-1 SPECT (TRODAT).
Methods: A cross-sectional study included PD patients diagnosed in accordance with United Kingdom PD Society Brain Bank criteria and a control group of age and sex- matched healthy subjects. All patients were examined by a movement disorder specialist and underwent brain SPECT using TRODAT, TCS examination and SST-16 test.
Purpose: To determine the normal optical nerve sheath (ONS) diameter ultrasonography (ONSUS) and evaluate the possible effects of drugs on ONS diameter during anesthetic induction in healthy pigs.
Methods: Healthy piglets were divided into three groups: a control group, that received xylazine and ketamine (X/K); other that received xylazine, ketamine and propofol (X/K/P); and a third group that received xylazine, ketamine, and thiopental (X/K/T). The sheath diameter was assessed by ultrasonography calculating the average of three measurements of each eye from the left and right sides.
J Child Neurol
May 2022
Sickle cell disease is the most prevalent hereditary disease in the country. The aim of this study was to use transcranial Doppler as a screening method for identifying cerebral vasculopathy in children with sickle cell disease. An epidemiologic, descriptive, and cross-sectional study was conducted.
View Article and Find Full Text PDFArq Neuropsiquiatr
April 2022
Background: Transcranial Doppler has been tested in the evaluation of cerebral hemodynamics as a non-invasive assessment of intracranial pressure (ICP), but there is controversy in the literature about its actual benefit and usefulness in this situation.
Objective: To investigate cerebral blood flow assessed by Doppler technique and correlate with the variations of the ICP in the acute phase of intracranial hypertension in an animal model.
Methods: An experimental animal model of intracranial hypertension was used.
Background: Early cranioplasty has been encouraged after decompressive craniectomy (DC), aiming to reduce consequences of atmospheric pressure over the opened skull. However, this practice may not be often available in low-middle-income countries (LMICs). We evaluated clinical improvement, hemodynamic changes in each hemisphere, and the hemodynamic balance between hemispheres after late cranioplasty in a LMIC, as the institution's routine resources allowed.
View Article and Find Full Text PDF: One of the possible mechanisms by which the new coronavirus (SARS-Cov2) could induce brain damage is the impairment of cerebrovascular hemodynamics (CVH) and intracranial compliance (ICC) due to the elevation of intracranial pressure (ICP). The main objective of this study was to assess the presence of CVH and ICC alterations in patients with COVID-19 and evaluate their association with short-term clinical outcomes. : Fifty consecutive critically ill COVID-19 patients were studied with transcranial Doppler (TCD) and non-invasive monitoring of ICC.
View Article and Find Full Text PDFThe purpose of this article is to introduce readers to the concept and structure of the CAAos (erebralutoregulationssessmentpenource) platform, and provide evidence of its functionality.The CAAos platform is a new open-source software research tool, developed in Python 3 language, that combines existing and novel methods for interactive visual inspection, batch processing and analysis of multichannel records. The platform is scalable, allowing for the customization and inclusion of new tools.
View Article and Find Full Text PDFBackground: Diagnosing brain death (BD) with accuracy and urgency is of great importance because an early diagnosis may guide the clinical management, optimize hospital beds, and facilitate organ transplantation. The clinical diagnosis of nonreactive and irreversible coma can be confirmed with additional tests. Among the complimentary exams that may testify brain circulatory arrest, transcranial Doppler (TCD) can be an option.
View Article and Find Full Text PDFIschemic stroke (IS) is one of the most impacting diseases in the world. In the last decades, new therapies have been introduced to improve outcomes after IS, most of them aiming for recanalization of the occluded vessel. However, despite this advance, there are still a large number of patients that remain disabled.
View Article and Find Full Text PDFBackground: Ultrasound of the optic nerve sheath diameter (ONSD) has been used as a non-invasive and cost-effective bedside alternative to invasive intracranial pressure (ICP) monitoring. However, ONSD time-lapse behavior in intracranial hypertension (ICH) and its relief by means of either saline infusion or surgery are still unknown. The objective of this study was to correlate intracranial pressure (ICP) and ultrasonography of the optic nerve sheath (ONS) in an experimental animal model of ICH and determine the interval needed for ONSD to return to baseline levels.
View Article and Find Full Text PDFSurg Radiol Anat
March 2021
Dual origin of the vertebral artery (VA) is an uncommon anatomical variation. We describe a case of duplication origin at right vertebral artery (RVA) found incidentally in one elderly patient on investigation for cerebral aneurysm. Angiogram study showed a pseudoaneurysm at V4 segment of the RVA associated with embryological anatomy.
View Article and Find Full Text PDFCerebral autoregulation (AR) keeps cerebral blood flow constant despite fluctuations in systemic arterial pressure. The final common AR pathway is made up of vasomotor adjustments of cerebrovascular resistance mediated by arterioles. Structural and functional changes in the arteriolar wall arise with age and systemic arterial hypertension.
View Article and Find Full Text PDFObjectives: To analyze the influences of mild and severe intracranial hypertension on cerebral autoregulation (CA).
Patients And Methods: Duroc piglets were monitored with an intracranial pressure (ICP) catheter. Intracranial hypertension was induced via infusion of 4 or 7 ml of saline solution by a bladder catheter that was inserted into the parietal lobe.
We hypothesized that knowledge of cerebral autoregulation (CA) status during recanalization therapies could guide further studies aimed at neuroprotection targeting penumbral tissue, especially in patients that do not respond to therapy. Thus, we assessed CA status of patients with acute ischemic stroke (AIS) during intravenous r-tPA therapy and associated CA with response to therapy. AIS patients eligible for intravenous r-tPA therapy were recruited.
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