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Transcranial doppler ultrasound

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https://www.readbyqxmd.com/read/28541158/noninvasive-optical-monitoring-of-critical-closing-pressure-and-arteriole-compliance-in-human-subjects
#1
Wesley B Baker, Ashwin B Parthasarathy, Kimberly P Gannon, Venkaiah C Kavuri, David R Busch, Kenneth Abramson, Lian He, Rickson C Mesquita, Michael T Mullen, John A Detre, Joel H Greenberg, Daniel J Licht, Ramani Balu, W Andrew Kofke, Arjun G Yodh
The critical closing pressure ( CrCP) of the cerebral circulation depends on both tissue intracranial pressure and vasomotor tone. CrCP defines the arterial blood pressure ( ABP) at which cerebral blood flow approaches zero, and their difference ( ABP -  CrCP) is an accurate estimate of cerebral perfusion pressure. Here we demonstrate a novel non-invasive technique for continuous monitoring of CrCP at the bedside. The methodology combines optical diffuse correlation spectroscopy (DCS) measurements of pulsatile cerebral blood flow in arterioles with concurrent ABP data during the cardiac cycle...
January 1, 2017: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/28539354/cerebral-oxygenation-and-regional-cerebral-perfusion-responses-with-resistance-breathing-during-central-hypovolemia
#2
Victoria L Kay, Justin Daniel Sprick, Caroline A Rickards
Resistance breathing improves tolerance to central hypovolemia induced by lower body negative pressure (LBNP), but this is not related to protection of anterior cerebral blood flow (indexed by mean middle cerebral artery velocity, MCAv). We hypothesized that inspiratory resistance breathing improves tolerance to central hypovolemia by maintaining cerebral oxygenation (ScO2), and protecting cerebral blood flow in the posterior cerebral circulation (indexed by posterior cerebral artery velocity, PCAv). Eight subjects (4M/4F) completed two experimental sessions of a presyncopal-limited LBNP protocol (3 mmHg/min onset rate) with and without (Control) resistance breathing via an impedance threshold device (ITD)...
May 24, 2017: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology
https://www.readbyqxmd.com/read/28537493/the-relationship-between-cerebral-vasoreactivity-and-post-concussive-symptom-severity
#3
Tamadher Albalawi, Jason W Hamner, Matthew Lapointe, William Meehan, Can Ozan Tan
While pathophysiology underlying post-concussion symptom burden is unknown, data suggest that cerebrovascular dysfunction may be among the culprits. We sought to determine whether the degree of impairment in the ability of cerebrovasculature to buffer against changes in arterial gases (vasoreactivity) is associated with concussion symptoms. In 15 participants (19±5 years, 1 week to 1 year post-injury) diagnosed with concussion, we assessed vasoreactivity from the slope of the linear relationship of beat-by-beat middle cerebral artery blood flow velocity (transcranial Doppler ultrasound) to end-tidal CO<sub>2</sub> during progressive increases in end-tidal CO<sub>2</sub> (air rebreathing)...
May 24, 2017: Journal of Neurotrauma
https://www.readbyqxmd.com/read/28503488/treatment-of-cerebral-vasospasm-in-an-infant-using-a-modified-dotter-technique
#4
Brian M Snelling, Samir Sur, Sumedh S Shah, Eric C Peterson
An 8-month old female presented with spontaneous subarachnoid hemorrhage and was treated successfully with endovascular coil embolization of the ruptured aneurysm. Transcranial Doppler ultrasound performed four days later demonstrated middle cerebral artery (MCA) velocities greater than 350 cm/sec on the right and greater than 200 cm/sec on the left, despite medical management. The patient demonstrated no focal neurological deficits, though examination was limited by our patient's sedation and intubation. Angiography revealed severe vasospasm of the supraclinoid internal carotid and MCA territories, bilaterally...
March 2017: Journal of Cerebrovascular and Endovascular Neurosurgery
https://www.readbyqxmd.com/read/28493931/asymptomatic-carotid-artery-stenosis-and-retinal-nerve-fiber-layer-thickness-a-community-based-observational-study
#5
Dandan Wang, Yang Li, Yong Zhou, Cheng Jin, Qi Zhao, Anxin Wang, Shouling Wu, Wen Bin Wei, Xingquan Zhao, Jost B Jonas
PURPOSE: To examine whether an abnormally thin retinal nerve fiber layer (RNFL) is associated with cerebrovascular insufficiency. DESIGN: Community-based study. METHODS: The Asymptomatic Polyvascular Abnormalities in Community Study included Chinese aged 40+ years and without histories of cerebrovascular incidents or coronary heart disease. Using transcranial Doppler and carotid duplex ultrasound examination, we assessed presence and degree of an intracranial arterial stenosis (ICAS) and extracranial carotid arterial stenosis (ECAS) and we measured the RNFL thickness by spectral-domain optical coherence tomography...
2017: PloS One
https://www.readbyqxmd.com/read/28487360/ultrasound-for-the-evaluation-of-stenosis-after-flow-diversion
#6
Cameron M McDougall, Khurshid Khan, Maher Saqqur, Andrew Jack, Jeremy Rempel, Carol Derksen, Yin Xi, Michael Chow
BACKGROUND AND PURPOSE: Flow diversion is a relatively new strategy used to treat complex cerebral aneurysms. The optimal method for radiographic follow-up of patients treated with flow diverters has not been established. The rate and clinical implications of in-stent stenosis for these devices is unclear. We evaluate the use of transcranial Doppler ultrasound (TCD) for follow-up of in-stent stenosis. MATERIALS AND METHODS: We analyzed 28 patients treated with the Pipeline embolization device (PED) over the course of 42 months from January 2009 to June 2012...
May 9, 2017: Journal of Neurointerventional Surgery
https://www.readbyqxmd.com/read/28484291/follow-up-of-vasospasm-by-transcranial-doppler-sonography-tcd-in-subarachnoid-hemorrhage-sah
#7
Jasminka Djelilovic-Vranic, Vanja Basic-Kes, Merita Tiric-Campara, Edina Djozic, Jasmin Kulenovic
INTRODUCTION: Subarachnoid hemorrhage (SAH)represents hemorrhage in the space between arachnoidea and pia mater, due to aneurysm burst, spontaneously or as a consequence of trauma. It is condition that occurs more common in women than men, and its most common complications are rebleeding and vazospasm. As a result of vasospasm, develops ischemia in the portion of brain tissue that can cause additional neurological deficit. Transcranial Doppler Sonography (TCD) is a noninvasive ultrasound diagnostic method that allows monitoring of the state of intracerebral hemodynamics...
March 2017: Acta Informatica Medica: AIM
https://www.readbyqxmd.com/read/28476311/transcranial-functional-ultrasound-imaging-in-freely-moving-awake-mice-and-anesthetized-young-rats-without-contrast-agent
#8
Elodie Tiran, Jérémy Ferrier, Thomas Deffieux, Jean-Luc Gennisson, Sophie Pezet, Zsolt Lenkei, Mickaël Tanter
Functional ultrasound (fUS) imaging by ultrasensitive Doppler detection of blood volume was previously reported to measure adult rat brain activation and functional connectivity with unmatched spatiotemporal sampling (100 μm, 1 ms), but skull-induced attenuation of ultrasonic waves imposed skull surgery or contrast agent use. Also, fUS feasibility remains to be validated in mice, a major pre-clinical model organism. In the study described here, we performed full-depth ultrasensitive Doppler imaging and 3-D Doppler tomography of the entire mouse brain under anesthesia, non-invasively through the intact skull and skin, without contrast agents...
May 2, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28465966/transcranial-doppler-ultrasound-incremental-diagnostic-role-in-cryptogenic-stroke-part-ii
#9
REVIEW
Antonello D'Andrea, Marianna Conte, Lucia Riegler, Raffaella Scarafile, Rosangela Cocchia, Enrica Pezzullo, Massimo Cavallaro, Marco Di Maio, Francesco Natale, Giuseppe Santoro, Maria Giovanna Russo, Marino Scherillo, Raffaele Calabrò
Transcranial Doppler (TCD) ultrasonography is a noninvasive ultrasound study, which has been extensively applied in both outpatient and inpatient settings. Its main use in current clinical practice is the research for "Paradoxical Embolism," due to migration of thromboembolic material from systemic venous circulation to the left cardiac chambers and arterial circulation through cardiopulmonary shunts such as patent foramen ovale which represents an important cause of cryptogenic stroke, especially in patients under 55 years of age...
July 2016: Journal of Cardiovascular Echography
https://www.readbyqxmd.com/read/28449077/executive-network-activation-is-linked-to-walking-speed-in-older-adults-functional-mri-and-tcd-ultrasound-evidence-from-the-mobilize-boston-study
#10
Azizah J Jor'dan, Victoria N Poole, Ikechukwu Iloputaife, William Milberg, Brad Manor, Michael Esterman, Lewis A Lipsitz
Background: Changes in cerebral blood flow velocity (CBF) in response to a cognitive task (task-related ΔCBF) have been shown by Transcranial Doppler ultrasonography (TCD) to be reduced in slow walkers. However, it is unknown whether reduced task-related ΔCBF is associated with reduced neural activity in specific brain regions, as measured by blood-oxygen-level dependent (BOLD) functional magnetic resonance imaging (fMRI). Methods: We assessed the regional changes in neural activity associated with reduced middle cerebral artery (MCA) task-related ΔCBF to an executive task and slow walking speed in 67 community-dwelling older adults from the MOBILIZE Boston Study...
April 26, 2017: Journals of Gerontology. Series A, Biological Sciences and Medical Sciences
https://www.readbyqxmd.com/read/28445296/a-case-of-cerebral-hyperperfusion-following-spontaneous-recanalization-of-occluded-middle-cerebral-artery-reperfusion-injury-or-true-cerebral-hyperperfusion-syndrome
#11
Ziqi Xu, Jiajia Zhou, Hui Liang, Benyan Luo, Ping Liu
BACKGROUND: Cerebral hyperperfusion syndrome (CHS) and reperfusion injury are distinct pathological phenomena. CASE SUMMARY: We present the case of a young ischemic stroke patient with middle cerebral artery (MCA) occlusion and spontaneous recanalization. Follow-up transcranial Doppler ultrasound showed high velocity flow in the left MCA, and neuroimaging revealed infarction, brain edema, artery dilatation, and hyperperfusion, consistent with both CHS and reperfusion injury...
April 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28440126/transcranial-doppler-screening-for-stroke-risk-in-children-with-sickle-cell-disease-a-systematic-review
#12
Sara Mazzucco, Marina Diomedi, Amrana Qureshi, Laura Sainati, Soundrie T Padayachee
Background Sickle cell disease (SCD) is one of the most common causes of stroke in children worldwide. Based on the results of the Stroke Prevention Trial in Sickle Cell Anemia (STOP), annual transcranial Doppler ultrasound (TCD) screening for affected children is standard practice. However, the need for TCD surveillance programs could override the accuracy of the screening, affecting the correct stratification of stroke risk and subsequent clinical management of the target population. Aims To shed light on this issue, a systematic review of the literature on TCD screening for children and adolescents with SCD was carried out (CRD42016050549), according to a list of clinically relevant questions, with a particular focus on screening practices in European countries...
January 1, 2017: International Journal of Stroke: Official Journal of the International Stroke Society
https://www.readbyqxmd.com/read/28431600/assessment-of-on-treatment-platelet-reactivity-and-relationship-with-cerebral-micro-embolic-signals-in-asymptomatic-and-symptomatic-carotid-stenosis
#13
Justin A Kinsella, W Oliver Tobin, Sean Tierney, Timothy M Feeley, Bridget Egan, Tara Coughlan, D Ronan Collins, Desmond O'Neill, Joseph A Harbison, Colin P Doherty, Prakash Madhavan, Dermot J Moore, Sean M O'Neill, Mary-Paula Colgan, Maher Saqqur, Raymond P Murphy, Niamh Moran, George Hamilton, Dominick J H McCabe
INTRODUCTION: The relationship between on-treatment platelet reactivity and cerebral micro-embolic signals (MES) is unknown, and has not been previously simultaneously assessed in asymptomatic and symptomatic carotid stenosis patients. METHODS: Consecutive eligible patients with ≥50% asymptomatic or recently symptomatic carotid stenosis (≤4weeks following TIA/ischaemic stroke) were recruited to this pilot study. Symptomatic patients were followed up to the 'late' phase (≥3months) following symptom onset or carotid intervention; longitudinal data were analysed from symptomatic patients with data available at both time-points...
May 15, 2017: Journal of the Neurological Sciences
https://www.readbyqxmd.com/read/28427768/syndrome-of-transient-headache-and-neurological-deficits-with-cerebrospinal-fluid-lymphocytosis-handl-in-a-patient-with-confusional-symptoms-diffuse-eeg-abnormalities-and-bilateral-vasospasm-in-transcranial-doppler-ultrasound-a-case-report-and-literature-review
#14
M Hidalgo de la Cruz, R Domínguez Rubio, E Luque Buzo, F Díaz Otero, P Vázquez Alén, J Orcajo Rincón, J Prieto Montalvo, A Contreras Chicote, F Grandas Pérez
INTRODUCTION: HaNDL syndrome (transient headache and neurological deficits with cerebrospinal fluid lymphocytosis) is characterised by one or more episodes of headache and transient neurological deficits associated with cerebrospinal fluid lymphocytosis. To date, few cases of HaNDL manifesting with confusional symptoms have been described. Likewise, very few patients with HaNDL and confusional symptoms have been evaluated with transcranial Doppler ultrasound (TCD). TCD data from patients with focal involvement reveal changes consistent with vasomotor alterations...
April 17, 2017: Neurología: Publicación Oficial de la Sociedad Española de Neurología
https://www.readbyqxmd.com/read/28417833/jugular-and-portal-vein-volume-middle-cerebral-vein-velocity-and-intracranial-pressure-in-dry-immersion
#15
Philippe Arbeille, Paul Avan, Loïc Treffel, Kathryn Zuj, Herve Normand, Pierre Denise
BACKGROUND: The objective was to determine if short term exposure to dry immersion (DI) results in a cephalic fluid shift similar to what has been observed with spaceflight. METHODS: Data were collected from 10 individuals at rest and during the first 2 h of dry immersion. Jugular vein (JV), portal vein (PV), and thyroid volume were measured using 3D echography. Middle cerebral vein velocity (MCVv) was determined using transcranial Doppler ultrasound. The cochlear response to audio stimulation was used to derive an estimate of intracranial pressure (dICP)...
May 1, 2017: Aerospace Medicine and Human Performance
https://www.readbyqxmd.com/read/28417646/cerebral-hemodynamic-assessment-and-neuroimaging-across-the-lifespan-in-sickle-cell-disease
#16
Lori C Jordan, Michael R DeBaun
Children and adults with sickle cell anemia (SCA) have a higher risk of strokes compared to age- and race-matched peers. Velocity in the middle cerebral or distal internal carotid artery as measured by transcranial Doppler ultrasound is a recognized method to identify children but not adults with SCA at high-risk for first stroke. For both children and adults with SCA that have had a stroke, no methods clearly identify individuals at highest risk of recurrent strokes or an initial silent stroke, the most common neurological injury...
January 1, 2017: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/28409398/middle-cerebral-artery-blood-flow-velocity-during-a-4%C3%A2-km-cycling-time-trial
#17
Ben Rattray, Brittany A Smale, Joseph M Northey, Disa J Smee, Nathan G Versey
PURPOSE: This study sought to describe middle cerebral artery blood flow velocity (MCAv) during a 4 km cycling time trial, and relate it to different pacing strategies adopted by participants. METHODS: After familiarisation and a standardised exercise protocol, 15 male trained cyclists rode a 4 km time trial on a cycling ergometer. MCAv was assessed via transcranial Doppler ultrasound in the right hemisphere at resting baseline, and throughout the time trial. Mean arterial pressure, end-tidal partial pressure of carbon dioxide (PetCO2) and heart rate were assessed alongside MCAv...
April 13, 2017: European Journal of Applied Physiology
https://www.readbyqxmd.com/read/28401995/orthostatic-dizziness-in-parkinson-s-disease-is-attributed-to-cerebral-hypoperfusion-a-transcranial-doppler-study
#18
Jinse Park, Hee-Tae Kim, Kang Min Park, Sam Yeol Ha, Sung Eun Kim, Kyong Jin Shin, Si Eun Kim, Wooyoung Jang, Ji Sun Kim, Jinyoung Youn, Engsoek Oh, Suyeon Park
OBJECTIVES: Orthostatic hypotension (OH) is controversially regarded as the cause of orthostatic dizziness in Parkinson's disease (PD). We sought to evaluate whether cerebral autoregulation is an alternative cause for orthostatic dizziness in PD patients, using transcranial Doppler monitoring during head-up tilting. METHODS: Forty-five PD patients with dizziness, 13 PD patients without dizziness, and 10 age-matched healthy controls were enrolled. Participants were divided into the following four groups: patients with dizziness and OH (group 1, n = 22), patients with dizziness but no OH (n = 23, group 2), patients without dizziness (n = 11, group 3), and age-matched healthy controls (n = 10, group 4)...
April 12, 2017: Journal of Clinical Ultrasound: JCU
https://www.readbyqxmd.com/read/28389602/shear-mediated-dilation-of-the-internal-carotid-artery-occurs-independent-of-hypercapnia
#19
Ryan L Hoiland, Kurt Jason Smith, Howard H Carter, Nia C S Lewis, Michael M Tymko, Kevin W Wildfong, Anthony R Bain, Daniel J Green, Philip N Ainslie
Evidence for shear stress as a regulator of carotid artery dilation in response to increased arterial carbon dioxide was recently demonstrated in humans during sustained elevations in CO2 (hypercapnia); however, the relative contributions of CO2 and shear stress to this response remains unclear. We examined the hypothesis that, following a 30-second transient increase in arterial CO2 tension and consequent increase in internal carotid artery shear stress, internal carotid artery diameter would increase, indicating shear-mediated dilation, in the absence of concurrent hypercapnia...
April 7, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/28388354/haemoglobin-oxygen-saturation-leucocyte-count-and-lactate-dehydrogenase-are-predictors-of-elevated-cerebral-blood-flow-velocity-in-nigerian-children-with-sickle-cell-anaemia
#20
Oyesola Oyewole Ojewunmi, Titilope Adenike Adeyemo, Akinniyi Adediran Osuntoki, Ngozi Awa Imaga, Ajoke Idayat Oyetunji
BACKGROUND: Transcranial Doppler ultrasound (TCD) scan, which measures blood flow velocity through the time-averaged mean of maximum velocities (TAMMVs) in the internal carotid arteries and middle cerebral arteries, is a useful screening tool for predicting stroke risk in children with sickle cell anaemia (SCA). AIM: To investigate which clinical and laboratory indices predict abnormal TCD velocity in children with SCA. METHODS: Fifty-four SCA patients with normal TCD (TAMMV < 170 cm/s), classified as negative TCD (NTCD), and 93 patients with conditional and abnormal TCD velocities (TAMMV ≥ 170 cm/s) classified as positive TCD were recruited...
April 7, 2017: Paediatrics and International Child Health
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