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Transcranial doppler ultrasound

Elisabeth B Marsh, Wendy C Ziai, Rafael H Llinas
INTRODUCTION: Reversible cerebral vasoconstriction syndrome (RCVS) typically affects young patients and left untreated can result in hemorrhage or ischemic stroke. Though the disorder has been well characterized in the literature, the most appropriate way to diagnose, treat, and evaluate therapeutic response remains unclear. In previous studies, transcranial Doppler ultrasound (TCD) has shown elevated velocities indicative of vasospasm. This imaging modality is noninvasive and inexpensive; an attractive option for diagnosis and therapeutic monitoring if it is sensitive enough to detect changes in the acute setting given that RCVS often affects the distal vessels early in the course of disease...
May 2016: Case Reports in Neurology
Rachel Wong, Rhenan Nealon, Daniel Raederstorff, Peter Howe
OBJECTIVE: Having shown that resveratrol consumption can improve flow mediated dilation of the brachial artery, we tested its effects on CVR to hypercapnia in adults with T2DM, a risk population for cerebrovascular disease and cognitive impairments. DESIGN AND METHOD: In a double-blind crossover trial, 34 adults with T2DM consumed 0, 75, 150 and 300 mg of synthetic trans-resveratrol (one dose per week in random order). Before and 1-2 hr after dosing, transcranial Doppler ultrasound was used to assess CVR to a hypercapnic stimulus (breathing Carbogen gas for 3 min) in the middle (MCA) and posterior (PCA) cerebral arteries...
September 2016: Journal of Hypertension
David Montero, Sven Rauber
BACKGROUND: It remains unknown whether brain perfusion is preserved and mirrored by middle cerebral blood flow velocity (MCA BFV) during prolonged changes in body posture. Herein, we examined the impact of sustained (180 min) 30° head-up (HUT) and head-down (HDT) tilt on brain perfusion, as determined by MCA BFV and blood flow in the extracranial arteries. METHODS: In 10 healthy male subjects, arterial diameters, BFVs, and blood flows were determined in the left internal carotid (ICA) and vertebral (VA) arteries using duplex Doppler ultrasound in supine rest, and 5, 20, 60, 120, and 180 min following 30° HUT and HDT...
August 2016: Aerospace Medicine and Human Performance
Michael M Tymko, Caroline A Rickards, Rachel J Skow, Nathan C Ingram-Cotton, Michael K Howatt, Trevor A Day
Steady-state tilt has no effect on cerebrovascular reactivity to increases in the partial pressure of end-tidal carbon dioxide (PETCO2). However, the anterior and posterior cerebral circulations may respond differently to a variety of stimuli that alter central blood volume, including lower body negative pressure (LBNP). Little is known about the superimposed effects of head-up tilt (HUT; decreased central blood volume and intracranial pressure) and head-down tilt (HDT; increased central blood volume and intracranial pressure), and LBNP on cerebral blood flow (CBF) responses...
September 2016: Physiological Reports
Robert J Adams, Dan T Lackland, Lynette Brown, David Brown, Jenifer Voeks, Heather J Fullerton, Julie Kanter, Janet L Kwiatkowski
In children with Sickle Cell Disease, the combination of risk stratification with Transcranial Doppler Ultrasound (TCD) and selective chronic red cell transfusion (CRCT-the STOP Protocol) is one of the most effective stroke prevention strategies in medicine. How fully it is being implemented is unclear. Nineteen of 26 sites that conducted the two pivotal clinical trials (STOP and STOP II) participated in Post STOP, a comprehensive medical records review assessing protocol implementation in the 10-15 years since the trials ended...
September 13, 2016: American Journal of Hematology
Christina D Bruce, Craig D Steinback, Uday V Chauhan, Jamie R Pfoh, Maria Abrosimova, Emily R Vanden Berg, Rachel J Skow, Margie H Davenport, Trevor A Day
The central respiratory chemoreflex contributes to blood gas homeostasis, particularly in response to accumulation of brainstem CO2 . Cerebrovascular reactivity (CVR) affects chemoreceptor stimulation inversely through CO2 washout from brainstem tissue. Voluntary breath-holding imposes alterations in blood gases, eliciting respiratory chemoreflexes, potentially contributing to breath-hold duration (i.e., break-point). However, the effects of cerebrovascular reactivity on break-point have yet to be determined...
September 12, 2016: Experimental Physiology
Devin S Muntz, David G Bundy, John J Strouse
OBJECTIVES: Transcranial Doppler ultrasound (TCD) effectively identifies children with sickle cell anemia (SCA) who are at increased risk of stroke. We evaluated a low-cost quality improvement (QI) intervention to increase the proportion of children screened by TCD. METHODS: We measured the proportion of children with SCA receiving appropriate TCD screening for increased cerebral blood velocity, a marker of stroke risk, for time periods before (April 1, 2009-July 1, 2010) and after (October 1, 2010-January 1, 2012) the implementation of a QI program...
September 2016: Southern Medical Journal
Przemyslaw Puz, Anetta Lasek-Bal, Tomasz Urbanek, Zofia Kazibutowska
AIM: Carotid artery stenosis can result in the brain tissue injury related to the intracranial aterial flow disturbances as well as microembolic complications. The choice of the proper therapy in patients with carotid artery stenosis, especially asymptomatic, remains still a significant clinical problem. The study aim was an assessment of the cerebral embolism and brain vascular reserve parameters in patients with carotid artery stenosis regarding the occurrence of the clinical symptoms, the degree of stenosis as well as plaque morphology...
2016: Neurologia i Neurochirurgia Polska
U Walter, S J Schreiber, M Kaps
Extra- and transcranial sonography of brain-supplying arteries is accepted worldwide in brain death protocols as a valid "ancillary" method of proving brain circulatory arrest. Color-coded duplex sonography and CT angiography have been newly incorporated in the fourth update of the German Medical Association's guidelines for the determination of the irreversible cessation of brain function ("brain death"), effective July 2015. The updated guidelines address in more detail the diagnostic procedures and the required qualifications of the examiners...
August 31, 2016: Ultraschall in der Medizin
Benjamin Hage, Mohammed Alwatban, Erin Barney, Mark Mills, Michael Dodd, Edward Truemper, Gregory Bashford
Functional transcranial Doppler ultrasound (fTCD) is a non-invasive sensing modality that measures blood flow velocities in cerebral arteries (CBFV) with high temporal resolution. CBFV change is correlated to changes in cerebral oxygen uptake, enabling fTCD to measure brain activity and lateralization with high accuracy. However, few studies have examined the relationship of CBFV change during visual search and visual memory tasks. Here a protocol to compare lateralization between these two similar cognitive tasks using fTCD is demonstrated...
August 26, 2016: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Ivan Rocha Ferreira da Silva, Gabriel Rodriguez de Freitas
BACKGROUND: Fever is commonly observed in patients who have had aneurysmal subarachnoid hemorrhage (SAH), and it has been associated with the occurrence of delayed cerebral ischemia and worse outcomes in previous studies. Frequently, fever is not the result of bacterial infections, and distinction between infection-related fever and fever secondary to brain injury (also referred as central fever) can be challenging. OBJECTIVES: The current study aimed to identify risk factors on admission for the development of central fever in patients with SAH...
August 23, 2016: Journal of Stroke and Cerebrovascular Diseases: the Official Journal of National Stroke Association
Dylan C Sieck, Matthew R Ely, Steven A Romero, Meredith J Luttrell, Pedro M Abdala, John R Halliwill
Adequate cerebral perfusion is necessary to maintain consciousness in upright humans. Following maximal anaerobic exercise, cerebral perfusion can become compromised and result in syncope. It is unknown whether post-exercise reductions in cerebral perfusion can lead to visual-cognitive deficits prior to the onset of syncope, which would be of concern for emergency workers and warfighters, where critical decision making and intense physical activity are combined. Therefore, the purpose of this experiment was to determine if reductions in cerebral blood velocity, induced by maximal anaerobic exercise and head-up tilt, result in visual-cognitive deficits prior to the onset of syncope...
August 2016: Physiological Reports
Fei Wu, Lei Huang, Gang Lu, Liang Ge, Xiaolong Zhang, Wenjie Cao, Qiang Dong
BACKGROUND/OBJECTIVE: We sought to assess the different patterns of cerebral hemodynamic changes in staged carotid angioplasty and stenting (CAS). METHODS: We prospectively recruited a cohort of patients with regular angioplasty or staged angioplasty from October 2013 to August 2015. The hemodynamic changes, including peak systolic, end-diastolic, and mean flow velocities in the ipsilateral middle cerebral artery (MCA) and the contralateral anterior cerebral artery (ACA), were recorded by transcranial Doppler ultrasound...
August 17, 2016: Journal of Stroke and Cerebrovascular Diseases: the Official Journal of National Stroke Association
J David Spence
In recent years, there have been a number of advances in the pathogenesis and treatment of atherosclerosis and in assessing prognosis in carotid atherosclerosis. Risk stratification to improve vascular prevention by identifying patients most likely to benefit from intensive therapy is much improved by measuring carotid plaque burden. In patients with asymptomatic carotid stenosis, a number of modalities can be used to identify the 10-15% who could benefit from endarterectomy or stenting. Transcranial Doppler embolus detection, echolucency and ulceration on 3D ultrasound, intraplaque hemorrhage on magnetic resonance imaging (MRI), and reduced cerebrovascular reserve are useful already; new approaches including plaque texture on ultrasound and imaging of plaque inflammation and early calcification on positron emission tomography/computed tomography (PET/CT) are in development...
2016: F1000Research
Nicolas Fanantenana Herinirina, Lova Hasina Ny Ony Narindra Rajaonarison, Andry Roussel Herijoelison, Olivat Aimée Alson Rakoto, Ahmad Ahmad
INTRODUCTION: Transcranial Doppler is an effective diagnostic tool to detect sickle cell children at risk for stroke. METHODS: We conducted a cross-sectional descriptive study of Malagasy children aged between 24 months and 15 years (group 1: 57 sickle cell diseases, group 2: 43 controls) to assess the cerebral artery velocimetry in the patient population. Transcranial doppler ultrasound with analysis of cerebral blood flow was performed in children of both groups...
2016: Pan African Medical Journal
Hai-Bo Wang, Daniel T Laskowitz, Jodi A Dodds, Gao-Qiang Xie, Pu-Hong Zhang, Yi-Ning Huang, Bo Wang, Yang-Feng Wu
BACKGROUND AND OBJECTIVE: It is necessary to develop an effective and low-cost screening tool for identifying Chinese people at high risk of stroke. Transcranial Doppler ultrasound (TCD) is a powerful predictor of stroke in the pediatric sickle cell disease population, as demonstrated in the STOP trial. Our study was conducted to determine the prediction value of peak systolic velocities as measured by TCD on subsequent stroke risk in a prospective cohort of the general population from Beijing, China...
2016: PloS One
E I Chukanova, Kh I Mamaeva, A S Chukanova
AIM: To study an effect of L-lysine aescinat on the dynamics of complaints, severity of neurological syndromes and parameters of cerebral blood flow estimated by transcranial doppler and duplex scanning in patients with chronic cerebral venous insufficiency (CCVI). MATERIAL AND METHODS: Eighty patients with ultrasound-confirmed CCVI were examined. The basic group included 40 patients who received two treatment courses (intravenous drop-by-drop/stream introductions of L-lysine aescinat in the dose of 5ml during 7 days in 2nd and 30th days of examination)...
2016: Zhurnal Nevrologii i Psikhiatrii Imeni S.S. Korsakova
M K Salem, H Z Butt, E Choke, D Moore, K West, T G Robinson, R D Sayers, A R Naylor, M J Bown
OBJECTIVE/BACKGROUND: The aim was to investigate the expression of genes associated with carotid plaque instability and their protein products at a local and systemic level. METHODS: Carotid plaques from 24 patients undergoing carotid endarterectomy (CEA) were classified as stable or unstable using clinical, histological, ultrasound, and transcranial Doppler criteria, and compared using whole genome microarray chips. Initial results of differentially expressed genes were validated by quantitative reverse transcriptase polymerase chain reaction in an independent group of 96 patients undergoing CEA...
October 2016: European Journal of Vascular and Endovascular Surgery
Jose A Egido, Ana M Garcia, Náyade Del Prado-Gonzalez, Manuel Fuentes-Ferrer, Marta Lopez-Herranz, Patricia Simal-Hernández, Cristina Fernández-Pérez
Sonographic tests are observer-dependent. With 1,527 consecutive patients, 22 trainees were assessed at baseline and after a hands-on 1:1 program, with a pre-examination median of 76 studies/trainee. We evaluated the required number of supervised examinations to reach a 0.80 kappa index (ki). Statistics included linear and exponential generalized estimating equation models. In the exponential model, 76 studies for carotid-duplex and >102 for vertebral-duplex and transcranial Doppler were needed for a 0.80 ki...
November 12, 2016: Journal of Clinical Ultrasound: JCU
Shizheng Wu, Guisheng Hao, Shukun Zhang, Dongmei Jiang, Tana Wuren, Junming Luo
The aim of the present study was to examine cerebral vasoconstriction in patients with chronic high altitude disease [cerebrovascular reactivity (CVR)], and to evaluate differences in alterations of brain vascular contractile reactivity of chronic mountain sickness (CMS) patients and healthy controls. Alterations of endothelin (ET) and its receptor, as well as endothelial nitric oxide synthase (eNOS) levels in the plasma were examined to determine the cerebral reservation capacities in CMS patients. Transcranial Doppler ultrasound and carbon dioxide analysis methods were used to detect the CVR variances...
September 2016: Molecular Medicine Reports
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