Umeå universitets logga

umu.sePublikationer
Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Hemodynamic Disturbances in Posterior Circulation Stroke: 4D Flow Magnetic Resonance Imaging Added to Computed Tomography Angiography
Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.ORCID-id: 0000-0001-6451-1940
Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.ORCID-id: 0000-0001-6331-4283
Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper. Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.ORCID-id: 0000-0002-0934-4534
Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).ORCID-id: 0000-0001-6402-0463
Visa övriga samt affilieringar
2021 (Engelska)Ingår i: Frontiers in Neuroscience, ISSN 1662-4548, E-ISSN 1662-453X, Vol. 15, artikel-id 656769Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Objective: A clinically feasible, non-invasive method to quantify blood flow, hemodynamics, and collateral flow in the vertebrobasilar arterial tree is missing. The objective of this study was to evaluate the feasibility of quantifying blood flow and blood flow patterns using 4D flow magnetic resonance imaging (MRI) in consecutive patients after an ischemic stroke in the posterior circulation. We also explore if 4D-flow, analyzed in conjunction with computed tomography angiography (CTA), has potential as a diagnostic tool in posterior circulation stroke.

Methods: Twenty-five patients (mean age 62 years; eight women) with acute ischemic stroke in the posterior circulation were investigated. At admission, all patients were examined with CTA followed by MRI (4D flow MRI and diffusion-weighted sequences) at median 4 days after the presenting event. Based on the classification of Caplan, patients were divided into proximal/middle (n = 16) and distal territory infarcts (n = 9). Absolute and relative blood flow rates were calculated for internal carotid arteries (ICA), vertebral arteries (VA), basilar artery (BA), posterior cerebral arteries (P1 and P2), and the posterior communicating arteries (Pcom). In a control group consisting of healthy elderly, the 90th and 10th percentiles of flow were calculated in order to define normal, increased, or decreased blood flow in each artery. “Major hemodynamic disturbance” was defined as low BA flow and either low P2 flow or high Pcom flow. Various minor hemodynamic disturbances were also defined. Blood flow rates were compared between groups. In addition, a comprehensive analysis of each patient’s blood flow profile was performed by assessing relative blood flow rates in each artery in conjunction with findings from CTA.

Results: There was no difference in total cerebral blood flow between patients and controls [604 ± 117 ml/min vs. 587 ± 169 ml/min (mean ± SD), p = 0.39] or in total inflow to the posterior circulation (i.e., the sum of total VA and Pcom flows, 159 ± 63 ml/min vs. 164 ± 52 ml/min, p = 0.98). In individual arteries, there were no significant differences between patients and controls in absolute or relative flow. However, patients had larger interindividual relative flow variance in BA, P1, and P2 (p = 0.01, <0.01, and 0.02, respectively). Out of the 16 patients that had proximal/middle territory infarcts, nine had CTA findings in VA and/or BA generating five with major hemodynamic disturbance identified with 4D flow MRI. For those without CTA findings, seven had no or minor 4D flow MRI hemodynamic disturbance. Among nine patients with distal territory infarcts, one had major hemodynamic disturbances, while the remaining had minor disturbances.

Conclusion: 4D flow MRI contributed to the identification of the patients who had major hemodynamic disturbances from the vascular pathologies revealed on CTA. We thus conclude that 4D flow MRI could add valuable hemodynamic information when used in conjunction with CTA.

Ort, förlag, år, upplaga, sidor
Frontiers Media S.A., 2021. Vol. 15, artikel-id 656769
Nyckelord [en]
basilar artery, blood flow, brain infarction, hemodynamics, magnetic resonance imaging, posterior cerebral artery, stroke, vertebral artery
Nationell ämneskategori
Radiologi och bildbehandling Neurologi
Forskningsämne
radiologi
Identifikatorer
URN: urn:nbn:se:umu:diva-188871DOI: 10.3389/fnins.2021.656769ISI: 000707751700001PubMedID: 34658752Scopus ID: 2-s2.0-85117091785OAI: oai:DiVA.org:umu-188871DiVA, id: diva2:1607616
Forskningsfinansiär
Vetenskapsrådet, 2015-05616Hjärt-Lungfonden, 20140592Hjärt-Lungfonden, 20180513Tillgänglig från: 2021-11-01 Skapad: 2021-11-01 Senast uppdaterad: 2024-04-29Bibliografiskt granskad
Ingår i avhandling
1. Cerebral hemodynamics in stroke, cerebral small vessel disease and pharmacological interventions: a 4D flow MRI study
Öppna denna publikation i ny flik eller fönster >>Cerebral hemodynamics in stroke, cerebral small vessel disease and pharmacological interventions: a 4D flow MRI study
2024 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Alternativ titel[sv]
Cerebral hemodynamik vid stroke, cerebral småkärlssjukdom och farmakologiska interventioner : en 4D flow MRI-studie
Abstract [en]

Background and aim: Current cerebrovascular imaging techniques provide important information on arterial anatomy and structural pathologies, such as stenoses and occlusions, but physicians are left to infer how the blood flow is affected. In addition, the relationship between blood pressure and cerebral blood flow is complex and poorly understood. Increased transmission of cardiac pulsatility to the cerebral microvasculature has been suggested as a causative factor of cerebral small vessel disease (CSVD) but previous research have yielded conflicting results regarding this relationship. 4D flow magnetic resonance imaging (MRI) is a novel and promising technique enabling time-resolved blood flow quantification with whole-brain coverage and relatively short scan times. However, despite its obvious potential, there is not yet an evidence-based application for the use of 4D flow MRI within stroke or CSVD. This dissertation aimed to apply 4D flow MRI to describe blood flow patterns in posterior circulation stroke and cerebral blood flow responses to common pharmacological agents used to alter arterial blood pressure as well as to examine the relationship between cerebral arterial pulsatility and CSVD.

Methods and Results: This doctoral dissertation consisted of four papers, referred to by roman numerals. 4D flow MRI and computed tomography angiography (CTA) were applied in 25 patients with acute ischemic stroke in the posterior circulation and a reference population of 15 healthy elderly (paper I). Individual flow profiles were created for each stroke patient and hemodynamic disturbances as well as collateral compensation were described. We show that hemodynamic findings were related to structural findings from CTA.

The cross-sectional relationship between cerebral arterial pulsatility (quantified using 4D flow MRI as pulsatility index [PI] and flow volume pulsatility [FVP]) and features of CSVD were examined using regression analysis in 89 patients with acute ischemic stroke (paper II) and a population-based sample of 862 elderly (paper III). Internal carotid artery FVP was associated with increasing white matter hyperintensity (WMH) volume in patients with stroke and TIA (paper II). In addition, increasing middle cerebral artery FVP and PI were associated with worse cognitive function. In the population sample, high FVP and PI were associated with increasing WMH volume, lower brain volume and the presence of lacunes, but not the composite MRI-CSVD (paper III). Among subjects with MRI-CSVD, displaying symptoms consistent with cerebral small vessel disease was associated with higher WMH volume, lower brain volume and active smoking, but not any measure of pulsatility.

Eighteen healthy volunteers were administered noradrenaline to increase mean arterial pressure by 20% above baseline, and labetalol to decrease mean arterial pressure to 15% below baseline (paper IV). Cerebral blood flow was measured using phase-contrast MRI at each blood pressure level and compared to baseline. Despite a marked increase in blood pressure, noradrenaline administration caused a reduction in cerebral blood flow and cardiac output. Meanwhile, labetalol administration caused no change in cerebral blood flow but an increased cardiac output.

Conclusions: 4D flow MRI can detect hemodynamic disturbances and discriminate between hemodynamic disturbances and normal flow in patients with structural vascular pathologies. This additional information compared to structural imaging alone could potentially be used for prognosis and selection for procedures in clinical care. Cerebral arterial pulsatility is modestly associated with several MRI and clinical features of CSVD but not all. Cerebral arterial pulsatility as the main risk factor of CSVD seems unlikely but its involvement in the pathophysiology cannot be ruled out. Raising the blood pressure with noradrenaline decreases cerebral blood flow and cardiac output without any redistribution from peripheral to cerebral flow. This highlights the pitfalls of using blood pressure as a surrogate for cerebral blood flow and questions the validity of our understanding of cerebral autoregulation. Lowering the blood pressure with labetalol does not affect cerebral blood flow, reassuring its use in clinical routine. 4D flow MRI can be integrated into an in-patient work-up in selected cases of acute ischemic stroke and into the workflow of large epidemiological studies.

Ort, förlag, år, upplaga, sidor
Umeå: Umeå University, 2024. s. 79
Serie
Umeå University medical dissertations, ISSN 0346-6612 ; 2304
Nyckelord
4D flow MRI, cerebral blood flow, cerebral arterial pulsatility, pulsatility index, stroke, cerebral small vessel disease, noradrenaline, labetalol, white matter hyperintensities, lacunes, perivascular spaces
Nationell ämneskategori
Neurologi
Forskningsämne
neurologi
Identifikatorer
urn:nbn:se:umu:diva-223865 (URN)978-91-8070-391-8 (ISBN)978-91-8070-392-5 (ISBN)
Disputation
2024-05-31, Betula, målpunkt L0, byggnad 6M, Norrlands universitetssjukhus, 09:00 (Svenska)
Opponent
Handledare
Tillgänglig från: 2024-05-08 Skapad: 2024-04-29 Senast uppdaterad: 2024-04-30Bibliografiskt granskad

Open Access i DiVA

fulltext(4379 kB)508 nedladdningar
Filinformation
Filnamn FULLTEXT01.pdfFilstorlek 4379 kBChecksumma SHA-512
00c5a3c57e87e9aa4e6db8792c166d4f5a10258901ff49e625eb75fcd5fc6320234e2272880dc4a3c673a7c6e6c5acf98bf176fd8f78e3ed147c94f89dcbc4e8
Typ fulltextMimetyp application/pdf

Övriga länkar

Förlagets fulltextPubMedScopus

Person

Malm, JanBirnefeld, JohanZarrinkoob, LalehWåhlin, AndersEklund, Anders

Sök vidare i DiVA

Av författaren/redaktören
Malm, JanBirnefeld, JohanZarrinkoob, LalehWåhlin, AndersEklund, Anders
Av organisationen
NeurovetenskaperAnestesiologi och intensivvårdRadiofysikUmeå centrum för funktionell hjärnavbildning (UFBI)Centrum för medicinsk teknik och fysik (CMTF)
I samma tidskrift
Frontiers in Neuroscience
Radiologi och bildbehandlingNeurologi

Sök vidare utanför DiVA

GoogleGoogle Scholar
Totalt: 508 nedladdningar
Antalet nedladdningar är summan av nedladdningar för alla fulltexter. Det kan inkludera t.ex tidigare versioner som nu inte längre är tillgängliga.

doi
pubmed
urn-nbn

Altmetricpoäng

doi
pubmed
urn-nbn
Totalt: 713 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf