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Rothenberger SM, Zhang J, Markl M, Craig BA, Vlachos PP, Rayz VL. 4D flow MRI velocity uncertainty quantification. Magn Reson Med 2024. [PMID: 39270010 DOI: 10.1002/mrm.30287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Revised: 07/27/2024] [Accepted: 08/20/2024] [Indexed: 09/15/2024]
Abstract
PURPOSE An automatic method is presented for estimating 4D flow MRI velocity measurement uncertainty in each voxel. The velocity distance (VD) metric, a statistical distance between the measured velocity and local error distribution, is introduced as a novel measure of 4D flow MRI velocity measurement quality. METHODS The method uses mass conservation to assess the local velocity error variance and the standardized difference of means (SDM) velocity to estimate the velocity error correlations. VD is evaluated as the Mahalanobis distance between the local velocity measurement and the local error distribution. The uncertainty model is validated synthetically and tested in vitro under different flow resolutions and noise levels. The VD's application is demonstrated on two in vivo thoracic vasculature 4D flow datasets. RESULTS Synthetic results show the proposed uncertainty quantification method is sensitive to aliased regions across various velocity-to-noise ratios and assesses velocity error correlations in four- and six-point acquisitions with correlation errors at or under 3.2%. In vitro results demonstrate the method's sensitivity to spatial resolution, venc settings, partial volume effects, and phase wrapping error sources. Applying VD to assess in vivo 4D flow MRI in the aorta demonstrates the expected increase in measured velocity quality with contrast administration and systolic flow. CONCLUSION The proposed 4D flow MRI uncertainty quantification method assesses velocity measurement error owing to sources including noise, intravoxel phase dispersion, and velocity aliasing. This method enables rigorous comparison of 4D flow MRI datasets obtained in longitudinal studies, across patient populations, and with different MRI systems.
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Affiliation(s)
- Sean M Rothenberger
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Jiacheng Zhang
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Michael Markl
- Department of Radiology at the Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Bruce A Craig
- Department of Statistics, Purdue University, West Lafayette, Indiana, USA
| | - Pavlos P Vlachos
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, USA
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Vitaliy L Rayz
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, USA
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana, USA
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Vuong TNAM, Bartolf‐Kopp M, Andelovic K, Jungst T, Farbehi N, Wise SG, Hayward C, Stevens MC, Rnjak‐Kovacina J. Integrating Computational and Biological Hemodynamic Approaches to Improve Modeling of Atherosclerotic Arteries. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2307627. [PMID: 38704690 PMCID: PMC11234431 DOI: 10.1002/advs.202307627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 03/12/2024] [Indexed: 05/07/2024]
Abstract
Atherosclerosis is the primary cause of cardiovascular disease, resulting in mortality, elevated healthcare costs, diminished productivity, and reduced quality of life for individuals and their communities. This is exacerbated by the limited understanding of its underlying causes and limitations in current therapeutic interventions, highlighting the need for sophisticated models of atherosclerosis. This review critically evaluates the computational and biological models of atherosclerosis, focusing on the study of hemodynamics in atherosclerotic coronary arteries. Computational models account for the geometrical complexities and hemodynamics of the blood vessels and stenoses, but they fail to capture the complex biological processes involved in atherosclerosis. Different in vitro and in vivo biological models can capture aspects of the biological complexity of healthy and stenosed vessels, but rarely mimic the human anatomy and physiological hemodynamics, and require significantly more time, cost, and resources. Therefore, emerging strategies are examined that integrate computational and biological models, and the potential of advances in imaging, biofabrication, and machine learning is explored in developing more effective models of atherosclerosis.
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Affiliation(s)
| | - Michael Bartolf‐Kopp
- Department of Functional Materials in Medicine and DentistryInstitute of Functional Materials and Biofabrication (IFB)KeyLab Polymers for Medicine of the Bavarian Polymer Institute (BPI)University of WürzburgPleicherwall 297070WürzburgGermany
| | - Kristina Andelovic
- Department of Functional Materials in Medicine and DentistryInstitute of Functional Materials and Biofabrication (IFB)KeyLab Polymers for Medicine of the Bavarian Polymer Institute (BPI)University of WürzburgPleicherwall 297070WürzburgGermany
| | - Tomasz Jungst
- Department of Functional Materials in Medicine and DentistryInstitute of Functional Materials and Biofabrication (IFB)KeyLab Polymers for Medicine of the Bavarian Polymer Institute (BPI)University of WürzburgPleicherwall 297070WürzburgGermany
- Department of Orthopedics, Regenerative Medicine Center UtrechtUniversity Medical Center UtrechtUtrecht3584Netherlands
| | - Nona Farbehi
- Graduate School of Biomedical EngineeringUniversity of New South WalesSydney2052Australia
- Tyree Institute of Health EngineeringUniversity of New South WalesSydneyNSW2052Australia
- Garvan Weizmann Center for Cellular GenomicsGarvan Institute of Medical ResearchSydneyNSW2010Australia
| | - Steven G. Wise
- School of Medical SciencesUniversity of SydneySydneyNSW2006Australia
| | - Christopher Hayward
- St Vincent's HospitalSydneyVictor Chang Cardiac Research InstituteSydney2010Australia
| | | | - Jelena Rnjak‐Kovacina
- Graduate School of Biomedical EngineeringUniversity of New South WalesSydney2052Australia
- Tyree Institute of Health EngineeringUniversity of New South WalesSydneyNSW2052Australia
- Australian Centre for NanoMedicine (ACN)University of New South WalesSydneyNSW2052Australia
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Rivera-Rivera LA, Vikner T, Eisenmenger L, Johnson SC, Johnson KM. Four-dimensional flow MRI for quantitative assessment of cerebrospinal fluid dynamics: Status and opportunities. NMR IN BIOMEDICINE 2024; 37:e5082. [PMID: 38124351 PMCID: PMC11162953 DOI: 10.1002/nbm.5082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 10/03/2023] [Accepted: 11/07/2023] [Indexed: 12/23/2023]
Abstract
Neurological disorders can manifest with altered neurofluid dynamics in different compartments of the central nervous system. These include alterations in cerebral blood flow, cerebrospinal fluid (CSF) flow, and tissue biomechanics. Noninvasive quantitative assessment of neurofluid flow and tissue motion is feasible with phase contrast magnetic resonance imaging (PC MRI). While two-dimensional (2D) PC MRI is routinely utilized in research and clinical settings to assess flow dynamics through a single imaging slice, comprehensive neurofluid dynamic assessment can be limited or impractical. Recently, four-dimensional (4D) flow MRI (or time-resolved three-dimensional PC with three-directional velocity encoding) has emerged as a powerful extension of 2D PC, allowing for large volumetric coverage of fluid velocities at high spatiotemporal resolution within clinically reasonable scan times. Yet, most 4D flow studies have focused on blood flow imaging. Characterizing CSF flow dynamics with 4D flow (i.e., 4D CSF flow) is of high interest to understand normal brain and spine physiology, but also to study neurological disorders such as dysfunctional brain metabolite waste clearance, where CSF dynamics appear to play an important role. However, 4D CSF flow imaging is challenged by the long T1 time of CSF and slower velocities compared with blood flow, which can result in longer scan times from low flip angles and extended motion-sensitive gradients, hindering clinical adoption. In this work, we review the state of 4D CSF flow MRI including challenges, novel solutions from current research and ongoing needs, examples of clinical and research applications, and discuss an outlook on the future of 4D CSF flow.
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Affiliation(s)
- Leonardo A Rivera-Rivera
- Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Tomas Vikner
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Radiation Sciences, Radiation Physics and Biomedical Engineering, Umeå University, Umeå, Sweden
| | - Laura Eisenmenger
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Sterling C Johnson
- Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Kevin M Johnson
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
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Wegener S, Baron JC, Derdeyn CP, Fierstra J, Fromm A, Klijn CJM, van Niftrik CHB, Schaafsma JD. Hemodynamic Stroke: Emerging Concepts, Risk Estimation, and Treatment. Stroke 2024; 55:1940-1950. [PMID: 38864227 DOI: 10.1161/strokeaha.123.044386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
Ischemic stroke can arise from the sudden occlusion of a brain-feeding artery by a clot (embolic), or local thrombosis. Hemodynamic stroke occurs when blood flow does not sufficiently meet the metabolic demand of a brain region at a certain time. This discrepancy between demand and supply can occur with cerebropetal arterial occlusion or high-grade stenosis but also arises with systemic conditions reducing blood pressure. Treatment of hemodynamic stroke is targeted toward increasing blood flow to the affected area by either systemically or locally enhancing perfusion. Thus, blood pressure is often maintained above normal values, and extra-intracranial flow augmentation bypass surgery is increasingly considered. Still, current evidence supporting the superiority of pressure or flow increase over conservative measures is limited. However, methods assessing hemodynamic impairment and identifying patients at risk of hemodynamic stroke are rapidly evolving. Sophisticated models incorporating clinical and imaging factors have been suggested to aid patient selection. In this narrative review, we provide current state-of-the-art knowledge about hemodynamic stroke, tools for assessment, and treatment options.
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Affiliation(s)
- Susanne Wegener
- Department of Neurology (S.W.), University Hospital Zurich (USZ) and University of Zurich (UZH), Switzerland
- Clinical Neurocenter Zurich and Neuroscience Center Zurich (ZNZ), Switzerland (S.W., J.F., C.H.B.v.N.)
| | - Jean Claude Baron
- Department of Neurology, GHU Paris Psychiatrie et Neurosciences, Hôpital Sainte-Anne, Université Paris Cité, Inserm U1266, FHU NeuroVasc, France (J.C.B.)
| | - Colin P Derdeyn
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, Charlottesville (C.P.D.)
| | - Jorn Fierstra
- Department of Neurosurgery (J.F., C.H.B.v.N.), University Hospital Zurich (USZ) and University of Zurich (UZH), Switzerland
- Clinical Neurocenter Zurich and Neuroscience Center Zurich (ZNZ), Switzerland (S.W., J.F., C.H.B.v.N.)
| | - Annette Fromm
- Department of Neurology, Haukeland University Hospital, Bergen, Norway (A.F.)
| | - Catharina J M Klijn
- Department of Neurology at Radboud University Nijmegen, the Netherlands (C.J.M.K.)
| | - Christiaan Hendrik Bas van Niftrik
- Department of Neurosurgery (J.F., C.H.B.v.N.), University Hospital Zurich (USZ) and University of Zurich (UZH), Switzerland
- Clinical Neurocenter Zurich and Neuroscience Center Zurich (ZNZ), Switzerland (S.W., J.F., C.H.B.v.N.)
| | - Joanna D Schaafsma
- Division of Neurology, Department of Medicine (JDS) and Division of Neuroradiology, Department of Medical Imaging, University Health Network, Toronto, Canada (DJM, DMM) (J.D.S.)
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5
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Raynaud Q, Di Domenicantonio G, Yerly J, Dardano T, van Heeswijk RB, Lutti A. A characterization of cardiac-induced noise in R 2 * maps of the brain. Magn Reson Med 2024; 91:237-251. [PMID: 37708206 DOI: 10.1002/mrm.29853] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/11/2023] [Accepted: 08/15/2023] [Indexed: 09/16/2023]
Abstract
PURPOSE Cardiac pulsation increases the noise level in brain maps of the transverse relaxation rate R2 *. Cardiac-induced noise is challenging to mitigate during the acquisition of R2 * mapping data because its characteristics are unknown. In this work, we aim to characterize cardiac-induced noise in brain maps of the MRI parameter R2 *. METHODS We designed a sampling strategy to acquire multi-echo 3D data in 12 intervals of the cardiac cycle, monitored with a fingertip pulse-oximeter. We measured the amplitude of cardiac-induced noise in this data and assessed the effect of cardiac pulsation on R2 * maps computed across echoes. The area of k-space that contains most of the cardiac-induced noise in R2 * maps was then identified. Based on these characteristics, we introduced a tentative sampling strategy that aims to mitigate cardiac-induced noise in R2 * maps of the brain. RESULTS In inferior brain regions, cardiac pulsation accounts for R2 * variations of up to 3 s-1 across the cardiac cycle (i.e., ∼35% of the overall variability). Cardiac-induced fluctuations occur throughout the cardiac cycle, with a reduced intensity during the first quarter of the cycle. A total of 50% to 60% of the overall cardiac-induced noise is localized near the k-space center (k < 0.074 mm-1 ). The tentative cardiac noise mitigation strategy reduced the variability of R2 * maps across repetitions by 11% in the brainstem and 6% across the whole brain. CONCLUSION We provide a characterization of cardiac-induced noise in brain R2 * maps that can be used as a basis for the design of mitigation strategies during data acquisition.
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Affiliation(s)
- Quentin Raynaud
- Laboratory for Research in Neuroimaging, Department for Clinical Neuroscience, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Giulia Di Domenicantonio
- Laboratory for Research in Neuroimaging, Department for Clinical Neuroscience, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Jérôme Yerly
- Department of Diagnostic and Interventional Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
- Center for Biomedical Imaging (CIBM), Lausanne, Switzerland
| | - Thomas Dardano
- Laboratory for Research in Neuroimaging, Department for Clinical Neuroscience, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Ruud B van Heeswijk
- Department of Diagnostic and Interventional Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Antoine Lutti
- Laboratory for Research in Neuroimaging, Department for Clinical Neuroscience, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
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Rothenberger SM, Patel NM, Zhang J, Schnell S, Craig BA, Ansari SA, Markl M, Vlachos PP, Rayz VL. Automatic 4D Flow MRI Segmentation Using the Standardized Difference of Means Velocity. IEEE TRANSACTIONS ON MEDICAL IMAGING 2023; 42:2360-2373. [PMID: 37028010 PMCID: PMC10474251 DOI: 10.1109/tmi.2023.3251734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We present a method to automatically segment 4D flow magnetic resonance imaging (MRI) by identifying net flow effects using the standardized difference of means (SDM) velocity. The SDM velocity quantifies the ratio between the net flow and observed flow pulsatility in each voxel. Vessel segmentation is performed using an F-test, identifying voxels with significantly higher SDM velocity values than background voxels. We compare the SDM segmentation algorithm against pseudo-complex difference (PCD) intensity segmentation of 4D flow measurements in in vitro cerebral aneurysm models and 10 in vitro Circle of Willis (CoW) datasets. We also compared the SDM algorithm to convolutional neural network (CNN) segmentation in 5 thoracic vasculature datasets. The in vitro flow phantom geometry is known, while the ground truth geometries for the CoW and thoracic aortas are derived from high-resolution time-of-flight (TOF) magnetic resonance angiography and manual segmentation, respectively. The SDM algorithm demonstrates greater robustness than PCD and CNN approaches and can be applied to 4D flow data from other vascular territories. The SDM to PCD comparison demonstrated an approximate 48% increase in sensitivity in vitro and 70% increase in the CoW, respectively; the SDM and CNN sensitivities were similar. The vessel surface derived from the SDM method was 46% closer to the in vitro surfaces and 72% closer to the in vitro TOF surfaces than the PCD approach. The SDM and CNN approaches both accurately identify vessel surfaces. The SDM algorithm is a repeatable segmentation method, enabling reliable computation of hemodynamic metrics associated with cardiovascular disease.
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Murata S, Takami M, Endo T, Hashizume H, Iwasaki H, Tsutsui S, Nagata K, Murakami K, Taiji R, Kozaki T, Heller JG, Yamada H. Using Electrical Stimulation of the Ulnar Nerve Trunk to Predict Postoperative Improvement in Hand Clumsiness in Patients With Cervical Spondylotic Myelopathy. Spine (Phila Pa 1976) 2023; 48:702-709. [PMID: 36730659 DOI: 10.1097/brs.0000000000004539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/21/2022] [Indexed: 02/04/2023]
Abstract
STUDY DESIGN A prospective cohort study. OBJECTIVE To investigate whether the immediate and short-term effects of preoperative electrical peripheral nerve stimulation (ePNS) on performance of the 10-second test could predict the early postoperative outcomes of patients with cervical spondylotic myelopathy (CSM). SUMMARY OF BACKGROUND DATA Previous studies have shown that early clinical improvement in CSM patients may be because of reversal of spinal cord ischemia after spinal cord compression. MATERIALS AND METHODS We conducted a 10-second test before surgery, after ePNS, and at discharge (one week after surgery) in 44 patients with CSM who underwent C3-C7 laminoplasty and evaluated their correlations. The effects of the procedures (ePNS or operation) and sides (stimulated or nonstimulated side) for the 10-second test were analyzed using repeated measures analysis of variance. The Pearson correlation coefficient was used to measure the relationship between the 10-second test values according to the method (after ePNS vs. surgery). In addition, the Bland-Altman method was used to evaluate the degree of agreement between the 10-second test obtained after ePNS versus shortly after surgery. RESULTS The preoperative 10-second test showed the most improvement immediately after the administration of ePNS, with a gradual decrease for the first 30 minutes after completion. After the initial 30 minutes, performance decreased rapidly, and by 60 minutes performance essentially returned to baseline. The 10-second post-ePNS had a strong positive correlation with the 10-second test in the early postoperative period (at discharge=one week after surgery). These phenomena were observed with the left hand, the side stimulated with ePNS, as well as the right hand, the side not stimulated. CONCLUSIONS Early postoperative outcomes after CSM surgery may be predicted by the results of preoperative ePNS. LEVEL OF EVIDENCE Level 3.
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Affiliation(s)
- Shizumasa Murata
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - Masanari Takami
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - Toru Endo
- Department of Orthopaedic Surgery, Endo Clinic, Otsu, Shiga, Japan
| | - Hiroshi Hashizume
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - Hiroshi Iwasaki
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - Shunji Tsutsui
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - Keiji Nagata
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - Kimihide Murakami
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - Ryo Taiji
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - Takuhei Kozaki
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - John G Heller
- Department of Orthopaedic Surgery, The Emory Spine Center, Emory Muskuloskeletal Institute, Atlanta, GA
| | - Hiroshi Yamada
- Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan
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Ferdian E, Marlevi D, Schollenberger J, Aristova M, Edelman ER, Schnell S, Figueroa CA, Nordsletten DA, Young AA. Cerebrovascular super-resolution 4D Flow MRI - Sequential combination of resolution enhancement by deep learning and physics-informed image processing to non-invasively quantify intracranial velocity, flow, and relative pressure. Med Image Anal 2023; 88:102831. [PMID: 37244143 DOI: 10.1016/j.media.2023.102831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 04/04/2023] [Accepted: 04/20/2023] [Indexed: 05/29/2023]
Abstract
The development of cerebrovascular disease is tightly coupled to regional changes in intracranial flow and relative pressure. Image-based assessment using phase contrast magnetic resonance imaging has particular promise for non-invasive full-field mapping of cerebrovascular hemodynamics. However, estimations are complicated by the narrow and tortuous intracranial vasculature, with accurate image-based quantification directly dependent on sufficient spatial resolution. Further, extended scan times are required for high-resolution acquisitions, and most clinical acquisitions are performed at comparably low resolution (>1 mm) where biases have been observed with regard to the quantification of both flow and relative pressure. The aim of our study was to develop an approach for quantitative intracranial super-resolution 4D Flow MRI, with effective resolution enhancement achieved by a dedicated deep residual network, and with accurate quantification of functional relative pressures achieved by subsequent physics-informed image processing. To achieve this, our two-step approach was trained and validated in a patient-specific in-silico cohort, showing good accuracy in estimating velocity (relative error: 15.0 ± 0.1%, mean absolute error (MAE): 0.07 ± 0.06 m/s, and cosine similarity: 0.99 ± 0.06 at peak velocity) and flow (relative error: 6.6 ± 4.7%, root mean square error (RMSE): 0.56 mL/s at peak flow), and with the coupled physics-informed image analysis allowing for maintained recovery of functional relative pressure throughout the circle of Willis (relative error: 11.0 ± 7.3%, RMSE: 0.3 ± 0.2 mmHg). Furthermore, the quantitative super-resolution approach is applied to an in-vivo volunteer cohort, effectively generating intracranial flow images at <0.5 mm resolution and showing reduced low-resolution bias in relative pressure estimation. Our work thus presents a promising two-step approach to non-invasively quantify cerebrovascular hemodynamics, being applicable to dedicated clinical cohorts in the future.
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Affiliation(s)
- E Ferdian
- University of Auckland, Auckland 1142 New Zealand
| | - D Marlevi
- Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | | | - M Aristova
- Northwestern University, Chicago, IL 60611, USA
| | - E R Edelman
- Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - S Schnell
- Northwestern University, Chicago, IL 60611, USA; University of Greifswald, Greifswald 17489, Germany
| | - C A Figueroa
- University of Michigan, Ann Arbor, MI 48109, USA
| | - D A Nordsletten
- University of Michigan, Ann Arbor, MI 48109, USA; King's College London, London, SE1 7EH, UK
| | - A A Young
- University of Auckland, Auckland 1142 New Zealand; King's College London, London, SE1 7EH, UK
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van den Kerkhof M, Jansen JFA, van Oostenbrugge RJ, Backes WH. 1D versus 3D blood flow velocity and pulsatility measurements of lenticulostriate arteries at 7T MRI. Magn Reson Imaging 2023; 96:144-150. [PMID: 36473545 DOI: 10.1016/j.mri.2022.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 11/21/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022]
Abstract
PURPOSE 7T MRI enables measurements of blood flow velocity waveforms in small, perforating cerebral arteries. As these vessels can be tortuous, acquisition methods sensitive to flow in only one direction may not be sufficient to accurately determine the dynamic blood flow velocity. In this study, we compared 1D with 3D velocity encoding to measure the blood flow velocity and pulsatility in the lenticulostriate arteries (LSAs). METHODS Blood flow velocity waveforms were measured in the LSAs of 18 subjects (age range: 20-74 years) using prospectively gated single-slice phase contrast (PC) MRI at 7T. For each subject, blood flow velocity waveforms were acquired in a single slice with one velocity encoding as well as three orthogonal velocity encodings. The peak velocity and pulsatility index (PI) were determined in the largest, perpendicularly planned LSA, one obliquely planned LSA and three smaller LSAs. The peak velocity and PI were compared between 1D and 3D measurements using Bland-Altman analysis, with the 95% limits of agreement (LOA) taken into account. RESULTS For the largest, perpendicularly planned LSA, the peak velocity was slightly lower (0.2 cm/s, 1.7%) for 1D compared to 3D measurements, with an LOA range from the mean difference of (-0.27;0.27). The PI was slightly higher (0.01, 1.6%) for the 1D measurement, and an LOA range from the mean difference in PI of (-0.045;0.045). The obliquely planned LSA and three smaller LSAs demonstrated larger deviations (range mean percentage difference: 3.9-8.2%). CONCLUSION 1D velocity encoding using 2D PC MRI provides sufficiently accurate dynamic velocity and pulsatility measurements in slices perpendicularly planned to single, large LSAs compared to 3D velocity encoding, while increasing errors are obtained with obliquely planned slices. A greater error is indicated when measuring multiple (possibly tortuous or obliquely planned) smaller LSAs in one scan using one-directional single-slice PC MRI.
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Affiliation(s)
- Marieke van den Kerkhof
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, PO Box 5800, 6202 AZ Maastricht, the Netherlands; School for Mental Health and Neuroscience, Maastricht University, PO Box 616, 6200 MD Maastricht, the Netherlands
| | - Jacobus F A Jansen
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, PO Box 5800, 6202 AZ Maastricht, the Netherlands; School for Mental Health and Neuroscience, Maastricht University, PO Box 616, 6200 MD Maastricht, the Netherlands; Department of Electrical Engineering, University of Eindhoven, PO Box 513, 5600 MB Eindhoven, the Netherlands
| | - Robert J van Oostenbrugge
- School for Mental Health and Neuroscience, Maastricht University, PO Box 616, 6200 MD Maastricht, the Netherlands; Department of Neurology, Maastricht University Medical Center, PO Box 5800, 6202 AZ Maastricht, the Netherlands; School for Cardiovascular Diseases, Maastricht University, PO Box 616, 6200 MD Maastricht, the Netherlands
| | - Walter H Backes
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, PO Box 5800, 6202 AZ Maastricht, the Netherlands; School for Mental Health and Neuroscience, Maastricht University, PO Box 616, 6200 MD Maastricht, the Netherlands; School for Cardiovascular Diseases, Maastricht University, PO Box 616, 6200 MD Maastricht, the Netherlands.
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Bai X, Fu M, Li Z, Gao P, Zhao H, Li R, Sui B. Distribution and regional variation of wall shear stress in the curved middle cerebral artery using four-dimensional flow magnetic resonance imaging. Quant Imaging Med Surg 2022; 12:5462-5473. [PMID: 36465823 PMCID: PMC9703110 DOI: 10.21037/qims-22-67] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 08/30/2022] [Indexed: 12/05/2023]
Abstract
BACKGROUND To investigate the distribution and regional variation of wall shear stress (WSS) in the curved middle cerebral artery (MCA) in healthy individuals using four-dimensional (4D) flow magnetic resonance imaging (MRI). METHODS A total of 44 healthy participants (18 males; mean ages: 27.16±5.69 years) were included in this cross-sectional study. The WSS parameters of mean, minimum, and maximum values, the coefficient of variation of time-averaged WSS (TAWSSCV), and the maximum values of the oscillatory shear index (OSI) were calculated and compared in the curved proximal (M1) segments. Three cross-sectional planes were selected: the location perpendicular to the beginning of the long axis of the curved M1 segment of the MCA (proximal section), the most curved M1 location (curved M1 section), and the location before the insular (M2) segment bifurcation (distal section). The WSS and OSI parameters of the proximal, curved, and distal sections of the curved M1 segment were compared, including the inner and outer curvatures of the curved M1 section. RESULTS Of the curved M1 segments, the curved M1 section had significantly lower minimum TAWSS values than the proximal (P=0.031) and distal sections (P=0.002), and the curved M1 section had significantly higher maximum OSI values than the distal section (P=0.001). The TAWSSCV values at the curved M1 section were significantly higher than the proximal (P=0.001) and distal sections (P<0.001). At the curved M1 section, the inner curvature showed a significantly lower minimum TAWSS (P=0.013) and higher maximum OSI values (P=0.002) than the outer curvature. CONCLUSIONS There are distribution variation of WSS and OSI parameters at the curved M1 section of the curved MCA, and the inner curvature of the curved M1 section has the lowest WSS and highest OSI distribution. The local hemodynamic features of the curved MCA may be related to the predilection for atherosclerotic plaque development.
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Affiliation(s)
- Xiaoyan Bai
- Tiantan Neuroimaging Center of Excellence, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
- Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Mingzhu Fu
- Center for Biomedical Imaging Research, Biomedical Engineering Department, School of Medicine, Tsinghua University, Beijing, China
| | - Zhiye Li
- Tiantan Neuroimaging Center of Excellence, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
- Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Peiyi Gao
- Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Haiqing Zhao
- Department of Radiology, Beijing Chui Yang Liu Hospital, Beijing, China
| | - Rui Li
- Center for Biomedical Imaging Research, Biomedical Engineering Department, School of Medicine, Tsinghua University, Beijing, China
| | - Binbin Sui
- Tiantan Neuroimaging Center of Excellence, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
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11
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Rivera-Rivera LA, Kecskemeti S, Jen ML, Miller Z, Johnson SC, Eisenmenger L, Johnson KM. Motion-corrected 4D-Flow MRI for neurovascular applications. Neuroimage 2022; 264:119711. [PMID: 36307060 PMCID: PMC9801539 DOI: 10.1016/j.neuroimage.2022.119711] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/10/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022] Open
Abstract
Neurovascular 4D-Flow MRI has emerged as a powerful tool for comprehensive cerebrovascular hemodynamic characterization. Clinical studies in at risk populations such as aging adults indicate hemodynamic markers can be confounded by motion-induced bias. This study develops and characterizes a high fidelity 3D self-navigation approach for retrospective rigid motion correction of neurovascular 4D-Flow data. A 3D radial trajectory with pseudorandom ordering was combined with a multi-resolution low rank regularization approach to enable high spatiotemporal resolution self-navigators from extremely undersampled data. Phantom and volunteer experiments were performed at 3.0T to evaluate the ability to correct for different amounts of induced motions. In addition, the approach was applied to clinical-research exams from ongoing aging studies to characterize performance in the clinical setting. Simulations, phantom and volunteer experiments with motion correction produced images with increased vessel conspicuity, reduced image blurring, and decreased variability in quantitative measures. Clinical exams revealed significant changes in hemodynamic parameters including blood flow rates, flow pulsatility index, and lumen areas after motion correction in probed cerebral arteries (Flow: P<0.001 Lt ICA, P=0.002 Rt ICA, P=0.004 Lt MCA, P=0.004 Rt MCA; Area: P<0.001 Lt ICA, P<0.001 Rt ICA, P=0.004 Lt MCA, P=0.004 Rt MCA; flow pulsatility index: P=0.042 Rt ICA, P=0.002 Lt MCA). Motion induced bias can lead to significant overestimation of hemodynamic markers in cerebral arteries. The proposed method reduces measurement bias from rigid motion in neurovascular 4D-Flow MRI in challenging populations such as aging adults.
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Affiliation(s)
- Leonardo A Rivera-Rivera
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, 1111 Highland Ave, Rm 1005, Madison, WI, 53705-2275, United States; Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53792, United States
| | - Steve Kecskemeti
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, 1111 Highland Ave, Rm 1005, Madison, WI, 53705-2275, United States
| | - Mu-Lan Jen
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, 1111 Highland Ave, Rm 1005, Madison, WI, 53705-2275, United States
| | - Zachary Miller
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, 1111 Highland Ave, Rm 1005, Madison, WI, 53705-2275, United States
| | - Sterling C Johnson
- Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53792, United States
| | - Laura Eisenmenger
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53792, United States
| | - Kevin M Johnson
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, 1111 Highland Ave, Rm 1005, Madison, WI, 53705-2275, United States; Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53792, United States.
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12
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Wang M, Yang Y, Zhang W, Zhou F, Zhang X, Zhang J, Zhang B. Risk Factors for Cerebrovascular Events in Moyamoya Angiopathy Using
4D
Flow
MRI
: A Pilot Study. J Magn Reson Imaging 2022. [DOI: 10.1002/jmri.28522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/21/2022] [Accepted: 10/21/2022] [Indexed: 11/10/2022] Open
Affiliation(s)
- Maoxue Wang
- Department of Radiology The Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing Jiangsu China
| | - Yongbo Yang
- Department of Neurosurgery The Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing Jiangsu China
| | - Wen Zhang
- Department of Radiology The Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing Jiangsu China
| | - Fei Zhou
- Department of Radiology The Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing Jiangsu China
| | - Xin Zhang
- Department of Radiology The Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing Jiangsu China
| | | | - Bing Zhang
- Department of Radiology The Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing Jiangsu China
- Institute of Medical Imaging and Artificial Intelligence Nanjing University Nanjing Jiangsu China
- Jiangsu Key Laboratory of Molecular Medicine Nanjing Jiangsu China
- Institute of Brain Science Nanjing University Nanjing Jiangsu China
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13
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Morphological changes in vertebral artery dissections observed on 4D flow magnetic resonance images: case report. Acta Neurochir (Wien) 2022; 164:2881-2886. [PMID: 35948733 DOI: 10.1007/s00701-022-05333-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 07/20/2022] [Indexed: 02/01/2023]
Abstract
The morphology of vertebral artery (VA) dissections can change in the clinical course. A 58-year-old female with a 2-week headache was diagnosed with left VA dissection. Hemodynamic stress on the right VA detected on 4D flow MRI scans resulted in increased wall shear stress but the vessel was morphologically unchanged. Subsequent MRA revealed right VA dissection. Her bilateral dissections were treated conservatively and no neurological abnormality developed. Serial 4D flow MRI may be useful for observing morphological changes in VA dissections and help to clarify the mechanism(s) underlying VA dissections.
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14
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Aristova M, Pang J, Ma Y, Ma L, Berhane H, Rayz V, Markl M, Schnell S. Accelerated dual-venc 4D flow MRI with variable high-venc spatial resolution for neurovascular applications. Magn Reson Med 2022; 88:1643-1658. [PMID: 35754143 PMCID: PMC9392495 DOI: 10.1002/mrm.29306] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 04/02/2022] [Accepted: 04/26/2022] [Indexed: 11/06/2022]
Abstract
PURPOSE Dual-velocity encoded (dual-venc or DV) 4D flow MRI achieves wide velocity dynamic range and velocity-to-noise ratio (VNR), enabling accurate neurovascular flow characterization. To reduce scan time, we present interleaved dual-venc 4D Flow with independently prescribed, prospectively undersampled spatial resolution of the high-venc (HV) acquisition: Variable Spatial Resolution Dual Venc (VSRDV). METHODS A prototype VSRDV sequence was developed based on a Cartesian acquisition with eight-point phase encoding, combining PEAK-GRAPPA acceleration with zero-filling in phase and partition directions for HV. The VSRDV approach was optimized by varying z, the zero-filling fraction of HV relative to low-venc, between 0%-80% in vitro (realistic neurovascular model with pulsatile flow) and in vivo (n = 10 volunteers). Antialiasing precision, mean and peak velocity quantification accuracy, and test-retest reproducibility were assessed relative to reference images with equal-resolution HV and low venc (z = 0%). RESULTS In vitro results for all z demonstrated an antialiasing true positive rate at least 95% for R PEAK - GRAPPA $$ {R}_{\mathrm{PEAK}-\mathrm{GRAPPA}} $$ = 2 and 5, with no linear relationship to z (p = 0.62 and 0.13, respectively). Bland-Altman analysis for z = 20%, 40%, 60%, or 80% versus z = 0% in vitro and in vivo demonstrated no bias >1% of venc in mean or peak velocity values at any R ZF $$ {R}_{\mathrm{ZF}} $$ . In vitro mean and peak velocity, and in vivo peak velocity, had limits of agreement within 15%. CONCLUSION VSRDV allows up to 34.8% scan time reduction compared to PEAK-GRAPPA accelerated DV 4D Flow MRI, enabling large spatial coverage and dynamic range while maintaining VNR and velocity measurement accuracy.
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Affiliation(s)
- Maria Aristova
- Department of RadiologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Jianing Pang
- Department of RadiologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
- MR R&D and CollaborationsSiemens Medical Solutions USA Inc.ChicagoILUSA
| | - Yue Ma
- Department of RadiologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
- Department of RadiologyShengjing Hospital of China Medical UniversityShenyangChina
| | - Liliana Ma
- Department of RadiologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
| | - Haben Berhane
- Department of RadiologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
- Department of Biomedical EngineeringNorthwestern University McCormick School of EngineeringEvanstonIllinoisUSA
| | - Vitaliy Rayz
- Weldon School of Biomedical EngineeringPurdue University College of EngineeringWest LafayetteIndianaUSA
| | - Michael Markl
- Department of RadiologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
- Department of Biomedical EngineeringNorthwestern University McCormick School of EngineeringEvanstonIllinoisUSA
| | - Susanne Schnell
- Department of RadiologyNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA
- Institut für PhysikUniversität GreifswaldGreifswaldGermany
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15
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Sakai Y, Lehman VT, Eisenmenger LB, Obusez EC, Kharal GA, Xiao J, Wang GJ, Fan Z, Cucchiara BL, Song JW. Vessel wall MR imaging of aortic arch, cervical carotid and intracranial arteries in patients with embolic stroke of undetermined source: A narrative review. Front Neurol 2022; 13:968390. [PMID: 35968273 PMCID: PMC9366886 DOI: 10.3389/fneur.2022.968390] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 07/01/2022] [Indexed: 11/13/2022] Open
Abstract
Despite advancements in multi-modal imaging techniques, a substantial portion of ischemic stroke patients today remain without a diagnosed etiology after conventional workup. Based on existing diagnostic criteria, these ischemic stroke patients are subcategorized into having cryptogenic stroke (CS) or embolic stroke of undetermined source (ESUS). There is growing evidence that in these patients, non-cardiogenic embolic sources, in particular non-stenosing atherosclerotic plaque, may have significant contributory roles in their ischemic strokes. Recent advancements in vessel wall MRI (VW-MRI) have enabled imaging of vessel walls beyond the degree of luminal stenosis, and allows further characterization of atherosclerotic plaque components. Using this imaging technique, we are able to identify potential imaging biomarkers of vulnerable atherosclerotic plaques such as intraplaque hemorrhage, lipid rich necrotic core, and thin or ruptured fibrous caps. This review focuses on the existing evidence on the advantages of utilizing VW-MRI in ischemic stroke patients to identify culprit plaques in key anatomical areas, namely the cervical carotid arteries, intracranial arteries, and the aortic arch. For each anatomical area, the literature on potential imaging biomarkers of vulnerable plaques on VW-MRI as well as the VW-MRI literature in ESUS and CS patients are reviewed. Future directions on further elucidating ESUS and CS by the use of VW-MRI as well as exciting emerging techniques are reviewed.
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Affiliation(s)
- Yu Sakai
- Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA, United States
| | - Vance T. Lehman
- Department of Radiology, The Mayo Clinic, Rochester, MN, United States
| | - Laura B. Eisenmenger
- Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States
| | | | - G. Abbas Kharal
- Department of Neurology, Cerebrovascular Center, Neurological Institute, Cleveland, OH, United States
| | - Jiayu Xiao
- Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Grace J. Wang
- Department of Vascular Surgery and Endovascular Therapy, Hospital of the University of Pennsylvania, Philadelphia, PA, United States
| | - Zhaoyang Fan
- Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Brett L. Cucchiara
- Department of Neurology, Hospital of the University of Pennsylvania, Philadelphia, PA, United States
| | - Jae W. Song
- Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA, United States
- *Correspondence: Jae W. Song
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16
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Rothenberger SM, Zhang J, Brindise MC, Schnell S, Markl M, Vlachos PP, Rayz VL. Modeling Bias Error in 4D Flow MRI Velocity Measurements. IEEE TRANSACTIONS ON MEDICAL IMAGING 2022; 41:1802-1812. [PMID: 35130153 PMCID: PMC9247036 DOI: 10.1109/tmi.2022.3149421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
We present a model to estimate the bias error of 4D flow magnetic resonance imaging (MRI) velocity measurements. The local instantaneous bias error is defined as the difference between the expectation of the voxel's measured velocity and actual velocity at the voxel center. The model accounts for bias error introduced by the intra-voxel velocity distribution and partial volume (PV) effects. We assess the intra-voxel velocity distribution using a 3D Taylor Series expansion. PV effects and numerical errors are considered using a Richardson extrapolation. The model is applied to synthetic Womersley flow and in vitro and in vivo 4D flow MRI measurements in a cerebral aneurysm. The bias error model is valid for measurements with at least 3.75 voxels across the vessel diameter and signal-to-noise ratio greater than 5. All test cases exceeded this diameter to voxel size ratio with diameters, isotropic voxel sizes, and velocity ranging from 3-15mm, 0.5-1mm, and 0-60cm/s, respectively. The model accurately estimates the bias error in voxels not affected by PV effects. In PV voxels, the bias error is an order of magnitude higher, and the accuracy of the bias error estimation in PV voxels ranges from 67.3% to 108% relative to the actual bias error. The bias error estimated for in vivo measurements increased two-fold at systole compared to diastole in partial volume and non-partial volume voxels, suggesting the bias error varies over the cardiac cycle. This bias error model quantifies 4D flow MRI measurement accuracy and can help plan 4D flow MRI scans.
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17
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Li S, Zhao W, Liu G, Ren C, Meng R, Wang Y, Song H, Ma Q, Ding Y, Ji X. Chronic remote ischemic conditioning for symptomatic internal carotid or middle cerebral artery occlusion: A prospective cohort study. CNS Neurosci Ther 2022; 28:1365-1371. [PMID: 35702956 PMCID: PMC9344079 DOI: 10.1111/cns.13874] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 05/12/2022] [Accepted: 05/13/2022] [Indexed: 01/05/2023] Open
Abstract
AIMS Remote ischemic conditioning (RIC) has been demonstrated to reduce recurrent stroke in patients with intracranial artery stenosis. This study aimed to evaluate the effects of RIC in patients with the symptomatic internal carotid artery (ICA) or middle cerebral artery (MCA) occlusion. METHODS This study is based on a high-volume single-center prospective cohort study in China, which included patients with symptomatic ICA or MCA occlusion with impaired hemodynamics and receiving chronic RIC. Clinical follow-up visits were performed regularly, and cardio-cerebrovascular events were assessed. RESULTS In total, 131 patients (68 with ICA occlusion and 63 with MCA occlusion; mean age, 52.6 ± 13.7 years; stroke, 73.5%; transient ischemic attack TIA, 26.5%) qualified for the analysis; the mean follow-up period was 8.8 years (range, 3-14 years). The compliance of RIC was 95.6 ± 3.7%, and no associated severe adverse events happened. The annual risk of ischemic stroke and ischemic cerebrovascular events was 2.4% and 3.3%, respectively. The cumulative probabilities of ischemic cerebrovascular events and major adverse cardiovascular and cerebrovascular events were 32.8% and 44.8% at 14 years, respectively. CONCLUSION In patients with symptomatic ICA or MCA occlusion with impaired hemodynamics, chronic RIC is well-tolerated, and it appears to be associated with a low annual risk of ischemic stroke and cardio-cerebrovascular events.
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Affiliation(s)
- Sijie Li
- Department of Emergency, Xuanwu Hospital, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Hypoxic Conditioning Translational Medicine, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Wenbo Zhao
- Beijing Key Laboratory of Hypoxic Conditioning Translational Medicine, Xuanwu Hospital, Capital Medical University, Beijing, China.,Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Guiyou Liu
- Department of Emergency, Xuanwu Hospital, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Changhong Ren
- Beijing Key Laboratory of Hypoxic Conditioning Translational Medicine, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Ran Meng
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Yuan Wang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Haiqing Song
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Qingfeng Ma
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Yuchuan Ding
- Department of Neurosurgery, Wayne State University School of Medicine, Detroit, MI, USA
| | - Xunming Ji
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
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18
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Pravdivtseva MS, Gaidzik F, Berg P, Ulloa P, Larsen N, Jansen O, Hövener JB, Salehi Ravesh M. Influence of Spatial Resolution and Compressed SENSE Acceleration Factor on Flow Quantification with 4D Flow MRI at 3 Tesla. Tomography 2022; 8:457-478. [PMID: 35202203 PMCID: PMC8880336 DOI: 10.3390/tomography8010038] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 01/30/2022] [Accepted: 01/31/2022] [Indexed: 11/25/2022] Open
Abstract
Four-dimensional (4D) flow MRI allows quantifying flow in blood vessels–non invasively and in vivo. The clinical use of 4D flow MRI in small vessels, however, is hampered by long examination times and limited spatial resolution. Compressed SENSE (CS-SENSE) is a technique that can accelerate 4D flow dramatically. Here, we investigated the effect of spatial resolution and CS acceleration on flow measurements by using 4D flow MRI in small vessels in vitro at 3 T. We compared the flow in silicon tubes (inner diameters of 2, 3, 4, and 5 mm) measured with 4D flow MRI, accelerated with four CS factors (CS = 2.5, 4.5, 6.5, and 13) and three voxel sizes (0.5, 1, and 1.5 mm3) to 2D flow MRI and a flow sensor. Additionally, the velocity field in an aneurysm model acquired with 4D flow MRI was compared to the one simulated with computational fluid dynamics (CFD). A strong correlation was observed between flow sensor, 2D flow MRI, and 4D flow MRI (rho > 0.94). The use of fewer than seven voxels per vessel diameter (nROI) resulted in an overestimation of flow in more than 5% of flow measured with 2D flow MRI. A negative correlation (rho = −0.81) between flow error and nROI were found for CS = 2.5 and 4.5. No statistically significant impact of CS factor on differences in flow rates was observed. However, a trend of increased flow error with increased CS factor was observed. In an aneurysm model, the peak velocity and stagnation zone were detected by CFD and all 4D flow MRI variants. The velocity difference error in the aneurysm sac did not exceed 11% for CS = 4.5 in comparison to CS = 2.5 for all spatial resolutions. Therefore, CS factors from 2.5–4.5 can appear suitable to improve spatial or temporal resolution for accurate quantification of flow rate and velocity. We encourage reporting the number of voxels per vessel diameter to standardize 4D flow MRI protocols.
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Affiliation(s)
- Mariya S. Pravdivtseva
- Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Kiel University, 24105 Kiel, Germany; (P.U.); (J.-B.H.); (M.S.R.)
- Correspondence: ; Tel.: +49-(0)-431-500-16-533
| | - Franziska Gaidzik
- Department of Fluid Dynamics and Technical Flows, Research Campus STIMULATE, Magdeburg University, 39106 Magdeburg, Germany; (F.G.); (P.B.)
| | - Philipp Berg
- Department of Fluid Dynamics and Technical Flows, Research Campus STIMULATE, Magdeburg University, 39106 Magdeburg, Germany; (F.G.); (P.B.)
| | - Patricia Ulloa
- Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Kiel University, 24105 Kiel, Germany; (P.U.); (J.-B.H.); (M.S.R.)
| | - Naomi Larsen
- Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel University, 24105 Kiel, Germany; (N.L.); (O.J.)
| | - Olav Jansen
- Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel University, 24105 Kiel, Germany; (N.L.); (O.J.)
| | - Jan-Bernd Hövener
- Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Kiel University, 24105 Kiel, Germany; (P.U.); (J.-B.H.); (M.S.R.)
| | - Mona Salehi Ravesh
- Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Kiel University, 24105 Kiel, Germany; (P.U.); (J.-B.H.); (M.S.R.)
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19
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Ha SY, Kang Y, Lee HJ, Hwang M, Baik J, Park S. Intracranial Flow Velocity Quantification Using Non-Contrast Four-Dimensional Flow MRI: A Prospective Comparative Study with Transcranial Doppler Ultrasound. Diagnostics (Basel) 2021; 12:diagnostics12010023. [PMID: 35054190 PMCID: PMC8774649 DOI: 10.3390/diagnostics12010023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/12/2021] [Accepted: 12/20/2021] [Indexed: 11/30/2022] Open
Abstract
Four-dimensional (4D) flow magnetic resonance imaging (MRI) allows three-dimensional velocity encoding to measure blood flow in a single scan, regardless of the intracranial artery direction. We compared blood flow velocity quantification by non-contrast 4D flow MRI and by transcranial Doppler ultrasound (TCD), the most widely used modality for measuring velocity. Twenty-two patients underwent both TCD and non-contrast 4D flow MRI. The mean time interval between TCD and non-contrast 4D flow MRI was 0.7 days. Subsegmental velocities were measured bilaterally in the middle cerebral and basilar arteries using TCD and non-contrast 4D flow MRI. Intracranial velocity measurements using TCD and non-contrast 4D flow MRI demonstrated a strong correlation in the bilateral M1, especially at the proximal segment (right r = 0.74, left r = 0.78; all p < 0.001). Mean velocities acquired with 4D flow MRI were approximately 8 to 10% lower than those acquired with TCD according to the location of M1. Intracranial arterial flow measurements estimated using non-contrast 4D flow MRI and TCD showed strong correlation. 4D flow MRI enables simultaneous assessment of vascular morphology and quantitative hemodynamic measurement, providing three-dimensional blood flow visualization. 4D flow MRI is a clinically useful sequence with a promising role in cerebrovascular disease.
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Affiliation(s)
- Sam-Yeol Ha
- Department of Neurology, Haeundae Paik Hospital, Inje University College of Medicine, Busan 48108, Korea; (S.-Y.H.); (S.P.)
- Department of Neurology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul 06973, Korea
| | - Yeonah Kang
- Department of Radiology, Haeundae Paik Hospital, Inje University College of Medicine, Busan 48108, Korea; (H.-J.L.); (J.B.)
- Correspondence: ; Tel.: +82-51-797-0340; Fax: +82-51-797-0379
| | - Ho-Joon Lee
- Department of Radiology, Haeundae Paik Hospital, Inje University College of Medicine, Busan 48108, Korea; (H.-J.L.); (J.B.)
| | | | - Jiyeon Baik
- Department of Radiology, Haeundae Paik Hospital, Inje University College of Medicine, Busan 48108, Korea; (H.-J.L.); (J.B.)
- Department of Radiology, Good Gang-An Hospital, Busan 48265, Korea
| | - Seongho Park
- Department of Neurology, Haeundae Paik Hospital, Inje University College of Medicine, Busan 48108, Korea; (S.-Y.H.); (S.P.)
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Malm J, Birnefeld J, Zarrinkoob L, Wåhlin A, Eklund A. Hemodynamic Disturbances in Posterior Circulation Stroke: 4D Flow Magnetic Resonance Imaging Added to Computed Tomography Angiography. Front Neurosci 2021; 15:656769. [PMID: 34658752 PMCID: PMC8514699 DOI: 10.3389/fnins.2021.656769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 08/18/2021] [Indexed: 11/13/2022] Open
Abstract
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.
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Affiliation(s)
- Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Johan Birnefeld
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Laleh Zarrinkoob
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden.,Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Centre for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
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21
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Björnfot C, Garpebring A, Qvarlander S, Malm J, Eklund A, Wåhlin A. Assessing cerebral arterial pulse wave velocity using 4D flow MRI. J Cereb Blood Flow Metab 2021; 41:2769-2777. [PMID: 33853409 PMCID: PMC8504412 DOI: 10.1177/0271678x211008744] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Intracranial arterial stiffening is a potential early marker of emerging cerebrovascular dysfunction and could be mechanistically involved in disease processes detrimental to brain function via several pathways. A prominent consequence of arterial wall stiffening is the increased velocity at which the systolic pressure pulse wave propagates through the vasculature. Previous non-invasive measurements of the pulse wave propagation have been performed on the aorta or extracranial arteries with results linking increased pulse wave velocity to brain pathology. However, there is a lack of intracranial "target-organ" measurements. Here we present a 4D flow MRI method to estimate pulse wave velocity in the intracranial vascular tree. The method utilizes the full detectable branching structure of the cerebral vascular tree in an optimization framework that exploits small temporal shifts that exists between waveforms sampled at varying depths in the vasculature. The method is shown to be stable in an internal consistency test, and of sufficient sensitivity to robustly detect age-related increases in intracranial pulse wave velocity.
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Affiliation(s)
- Cecilia Björnfot
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Cecilia Björnfot, Department of Radiation Sciences, Umeå University, Umeå SE 901 87, Sweden.
| | | | - Sara Qvarlander
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
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22
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Vikner T, Eklund A, Karalija N, Malm J, Riklund K, Lindenberger U, Bäckman L, Nyberg L, Wåhlin A. Cerebral arterial pulsatility is linked to hippocampal microvascular function and episodic memory in healthy older adults. J Cereb Blood Flow Metab 2021; 41:1778-1790. [PMID: 33444091 PMCID: PMC8217890 DOI: 10.1177/0271678x20980652] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Microvascular damage in the hippocampus is emerging as a central cause of cognitive decline and dementia in aging. This could be a consequence of age-related decreases in vascular elasticity, exposing hippocampal capillaries to excessive cardiac-related pulsatile flow that disrupts the blood-brain barrier and the neurovascular unit. Previous studies have found altered intracranial hemodynamics in cognitive impairment and dementia, as well as negative associations between pulsatility and hippocampal volume. However, evidence linking features of the cerebral arterial flow waveform to hippocampal function is lacking. We used a high-resolution 4D flow MRI approach to estimate global representations of the time-resolved flow waveform in distal cortical arteries and in proximal arteries feeding the brain in healthy older adults. Waveform-based clustering revealed a group of individuals featuring steep systolic onset and high amplitude that had poorer hippocampus-sensitive episodic memory (p = 0.003), lower whole-brain perfusion (p = 0.001), and weaker microvascular low-frequency oscillations in the hippocampus (p = 0.035) and parahippocampal gyrus (p = 0.005), potentially indicating compromised neurovascular unit integrity. Our findings suggest that aberrant hemodynamic forces contribute to cerebral microvascular and hippocampal dysfunction in aging.
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Affiliation(s)
- Tomas Vikner
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Nina Karalija
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Katrine Riklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Ulman Lindenberger
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany.,Max Planck, UCL Centre for Computational Psychiatry and Ageing Research, Berlin, Germany.,Max Planck, UCL Centre for Computational Psychiatry and Ageing Research, London, UK
| | - Lars Bäckman
- Ageing Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden
| | - Lars Nyberg
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden.,Department of Integrative Medical Biology (IMB), Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
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Sleight E, Stringer MS, Marshall I, Wardlaw JM, Thrippleton MJ. Cerebrovascular Reactivity Measurement Using Magnetic Resonance Imaging: A Systematic Review. Front Physiol 2021; 12:643468. [PMID: 33716793 PMCID: PMC7947694 DOI: 10.3389/fphys.2021.643468] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/01/2021] [Indexed: 12/27/2022] Open
Abstract
Cerebrovascular reactivity (CVR) magnetic resonance imaging (MRI) probes cerebral haemodynamic changes in response to a vasodilatory stimulus. CVR closely relates to the health of the vasculature and is therefore a key parameter for studying cerebrovascular diseases such as stroke, small vessel disease and dementias. MRI allows in vivo measurement of CVR but several different methods have been presented in the literature, differing in pulse sequence, hardware requirements, stimulus and image processing technique. We systematically reviewed publications measuring CVR using MRI up to June 2020, identifying 235 relevant papers. We summarised the acquisition methods, experimental parameters, hardware and CVR quantification approaches used, clinical populations investigated, and corresponding summary CVR measures. CVR was investigated in many pathologies such as steno-occlusive diseases, dementia and small vessel disease and is generally lower in patients than in healthy controls. Blood oxygen level dependent (BOLD) acquisitions with fixed inspired CO2 gas or end-tidal CO2 forcing stimulus are the most commonly used methods. General linear modelling of the MRI signal with end-tidal CO2 as the regressor is the most frequently used method to compute CVR. Our survey of CVR measurement approaches and applications will help researchers to identify good practice and provide objective information to inform the development of future consensus recommendations.
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Affiliation(s)
- Emilie Sleight
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Michael S. Stringer
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom,*Correspondence: Michael S. Stringer
| | - Ian Marshall
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Joanna M. Wardlaw
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Michael J. Thrippleton
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
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