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Santhumayor BA, White TG, Golub D, Rivera M, Turpin J, Golombeck D, Ryu B, Shah K, Ortiz R, Black K, Katz JM, Dehdashti AR, Langer DJ. Impact of Cerebral Revascularization on Pial Collateral Flow in Patients With Unilateral Moyamoya Disease Using Quantitative Magnetic Resonance Angiography. Neurosurgery 2024; 95:596-604. [PMID: 38501815 DOI: 10.1227/neu.0000000000002905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 01/12/2024] [Indexed: 03/20/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Moyamoya disease (MMD) is a chronic steno-occlusive disease of the intracranial circulation that depends on neoangiogenesis of collateral vessels to maintain cerebral perfusion and is primarily managed with cerebral revascularization surgery. A quantitative assessment of preoperative and postoperative collateral flow using quantitative magnetic resonance angiography with noninvasive optimal vessel analysis (NOVA) was used to illustrate the impact of revascularization on cerebral flow distribution. METHODS A retrospective review of patients with unilateral MMD who underwent direct, indirect, or combined direct/indirect cerebral revascularization surgery was conducted between 2011 and 2020. Using NOVA, flow was measured at the anterior cerebral artery (ACA), ACA distal to the anterior communicating artery (A2), middle cerebral artery (MCA), posterior cerebral artery (PCA), and PCA distal to the posterior communicating artery (P2). Pial flow (A2 + P2) and collateral flow (ipsilateral [A2 + P2])-(contralateral [A2 + P2]) were measured and compared before and after revascularization surgery. Total hemispheric flow (MCA + A2 + P2) with the addition of the bypass graft flow postoperatively was likewise measured. RESULTS Thirty-four patients with unilateral MMD underwent cerebral revascularization. Median collateral flow significantly decreased from 68 to 39.5 mL/min ( P = .007) after bypass. Hemispheres with maintained measurable bypass signal on postoperative NOVA demonstrated significant reduction in median collateral flow after bypass ( P = .002). Median total hemispheric flow significantly increased from 227 mL/min to 247 mL/min ( P = .007) after bypass. Only one patient suffered an ipsilateral ischemic stroke, and no patients suffered a hemorrhage during follow-up. CONCLUSION NOVA measurements demonstrate a reduction in pial collateral flow and an increase in total hemispheric flow after bypass for MMD, likely representing a decrease in leptomeningeal collateral stress on the distal ACA and PCA territories. Further studies with these measures in larger cohorts may elucidate a role for NOVA in predicting the risk of ischemic and hemorrhagic events in MMD.
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Affiliation(s)
- Brandon A Santhumayor
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - Timothy G White
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - Danielle Golub
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - Moses Rivera
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - Justin Turpin
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - David Golombeck
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - Brendan Ryu
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - Kevin Shah
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - Rafael Ortiz
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
- Current Affiliation: Department of Neurosurgery, White Plains Hospital, White Plains , New York , USA
| | - Karen Black
- Department of Radiology, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - Jeffrey M Katz
- Department of Neurology, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - Amir R Dehdashti
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
| | - David J Langer
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead , New York , USA
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Correia de Verdier M, Ronne-Engström E, Borota L, Wikström J. Hemodynamic evaluation of intracranial arteriovenous malformations: Pre- and post-treatment 2D phase-contrast MRI measurements. Acta Radiol Open 2024; 13:20584601241269608. [PMID: 39131056 PMCID: PMC11311173 DOI: 10.1177/20584601241269608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 07/20/2024] [Indexed: 08/13/2024] Open
Abstract
Background Hemodynamic changes are seen in the feeding arteries of arteriovenous malformations (AVMs). Phase-contrast MRI (PC-MRI) enables the acquisition of hemodynamic information from blood vessels. There is insufficient knowledge on which flow or velocity parameter best discriminates AVMs from healthy subjects. Purpose To evaluate PC-MRI-measured flow and velocity in feeding arteries of AVMs before and, when possible, also after treatment and to compare these measurements to corresponding measurements in healthy controls. Materials and Methods Highest flow (HF), lowest flow (LF), mean flow (MF), peak systolic velocity (PSV), end-diastolic velocity (EDV), and mean velocity (MV) were measured in feeding arteries in patients with intracranial AVMs using 2D PC-MRI at 3 T. Measurements were compared to previously reported values in healthy individuals. Values in patients above the 95th percentile in the healthy cohort were categorized as pathological. Nidus volume was measured using 3D time-of-flight MR angiography. Results Ten patients with diagnosed AVMs were examined with PC-MRI. Among these, three patients also underwent follow-up PC-MRI after treatment. Pathological velocities (PSV, EDV, and MV) were seen in all five subjects with a nidus larger or equal to 5.7 cm3, whereas pathological flow values were not seen in all, that is, pathologic HF in three, pathologic LF in two, and pathologic MF in two. After treatment, there was a decrease in flow and velocity (all measured parameters). After treatment, velocities (PSV, EDV, and MV) were no longer abnormal compared to healthy controls. Conclusion Patients with a large AVM nidus show pathological velocities, but less consistent flow increases. Following treatment, velocities normalize.
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Affiliation(s)
| | | | - Ljubisa Borota
- Department of Surgical Sciences, Section of Neuroradiology, Uppsala University, Uppsala, Sweden
| | - Johan Wikström
- Department of Surgical Sciences, Section of Neuroradiology, Uppsala University, Uppsala, Sweden
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Li J, Li D, Alaraj A, Du X, Wang K, Charbel FT. A patient-specific circle of Willis blood flow model in predicting outcomes of balloon test occlusion. J Neuroimaging 2024; 34:438-444. [PMID: 38520082 DOI: 10.1111/jon.13198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/05/2024] [Accepted: 03/07/2024] [Indexed: 03/25/2024] Open
Abstract
BACKGROUND AND PURPOSE Balloon test occlusion (BTO) evaluates cerebral ischemic tolerance before internal carotid artery (ICA) sacrifice but carries risks like dissection and thrombosis. This study introduces a new approach using a patient-specific circle of Willis (COW) blood flow model, based on non-invasive quantitative MR angiography (qMRA) measurements, to predict the outcomes of BTO. METHODS We developed individualized COW blood flow models for 43 patients undergoing BTO. These models simulated blood flow and pressure under normal conditions and with the ICA occlusion. We then compared the model's predictions of blood flow changes due to the simulated ICA occlusion to actual qMRA measurements before the BTO. RESULTS For all 31 BTO failures, the ipsilateral hemisphere showed an average flow decrease of 15 ± 10% (mean ± standard deviation), compared to 3 ± 2% in the contralateral hemisphere. In all 12 BTO passes, these figures were 6 ± 3% and 1 ± 0.8%, respectively. Notably, all BTO passes had less than a 10% reduction in the ipsilateral hemisphere. In contrast, 65% of BTO failures and 67% single-photon emission computed tomography (SPECT) failures exhibited a decrease of 10% or more in the same region. CONCLUSION Blood flow reduction exceeding 10% in the ipsilateral hemisphere during BTO is a strong predictor of failure in both BTO and SPECT. Our patient-specific COW blood flow models, incorporating detailed flow and arterial geometry data, offered valuable insights for predicting BTO outcomes. These models are especially beneficial for situations where conducting BTO or SPECT is clinically impractical.
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Affiliation(s)
- Jianmin Li
- Department of Neurosurgery, University of Illinois Chicago, Chicago, Illinois, USA
| | - Daniel Li
- Department of Orthopedics, The Ohio State University, Columbus, Ohio, USA
| | - Ali Alaraj
- Department of Neurosurgery, University of Illinois Chicago, Chicago, Illinois, USA
| | - Xinjian Du
- Department of Neurosurgery, University of Illinois Chicago, Chicago, Illinois, USA
| | | | - Fady T Charbel
- Department of Neurosurgery, University of Illinois Chicago, Chicago, Illinois, USA
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4
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Slovis JC, Bach A, Beaulieu F, Zuckerberg G, Topjian A, Kirschen MP. Neuromonitoring after Pediatric Cardiac Arrest: Cerebral Physiology and Injury Stratification. Neurocrit Care 2024; 40:99-115. [PMID: 37002474 PMCID: PMC10544744 DOI: 10.1007/s12028-023-01685-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 01/30/2023] [Indexed: 04/03/2023]
Abstract
BACKGROUND Significant long-term neurologic disability occurs in survivors of pediatric cardiac arrest, primarily due to hypoxic-ischemic brain injury. Postresuscitation care focuses on preventing secondary injury and the pathophysiologic cascade that leads to neuronal cell death. These injury processes include reperfusion injury, perturbations in cerebral blood flow, disturbed oxygen metabolism, impaired autoregulation, cerebral edema, and hyperthermia. Postresuscitation care also focuses on early injury stratification to allow clinicians to identify patients who could benefit from neuroprotective interventions in clinical trials and enable targeted therapeutics. METHODS In this review, we provide an overview of postcardiac arrest pathophysiology, explore the role of neuromonitoring in understanding postcardiac arrest cerebral physiology, and summarize the evidence supporting the use of neuromonitoring devices to guide pediatric postcardiac arrest care. We provide an in-depth review of the neuromonitoring modalities that measure cerebral perfusion, oxygenation, and function, as well as neuroimaging, serum biomarkers, and the implications of targeted temperature management. RESULTS For each modality, we provide an in-depth review of its impact on treatment, its ability to stratify hypoxic-ischemic brain injury severity, and its role in neuroprognostication. CONCLUSION Potential therapeutic targets and future directions are discussed, with the hope that multimodality monitoring can shift postarrest care from a one-size-fits-all model to an individualized model that uses cerebrovascular physiology to reduce secondary brain injury, increase accuracy of neuroprognostication, and improve outcomes.
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Affiliation(s)
- Julia C Slovis
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood - 6105, Philadelphia, PA, 19104, USA.
| | - Ashley Bach
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood - 6105, Philadelphia, PA, 19104, USA
| | - Forrest Beaulieu
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood - 6105, Philadelphia, PA, 19104, USA
| | - Gabe Zuckerberg
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood - 6105, Philadelphia, PA, 19104, USA
| | - Alexis Topjian
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood - 6105, Philadelphia, PA, 19104, USA
| | - Matthew P Kirschen
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, 6 Wood - 6105, Philadelphia, PA, 19104, USA
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Dunn L, Wang Y, Kass-Hout T, Chiu D. Randomized Secondary Prevention Trials in Participants With Symptomatic Intracranial Atherosclerotic Stenosis. Stroke 2024; 55:324-334. [PMID: 38252760 PMCID: PMC11008430 DOI: 10.1161/strokeaha.123.043632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Intracranial atherosclerotic stenosis is a prevalent cause of ischemic stroke worldwide. Its association with silent cerebral infarcts and its contribution to cognitive impairment and dementia emphasize the critical need for disease prevention and effective management strategies. Despite extensive research on secondary stroke prevention treatment over the past several decades, intracranial atherosclerotic stenosis continues to exhibit a notably higher recurrent stroke rate compared with other causes. This review focuses on randomized secondary prevention trials involving antithrombotic therapy, endovascular treatment, open surgical therapy, and remote ischemic conditioning. It aims to provide an insightful overview of the major findings from each trial and their implications for future research efforts.
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Affiliation(s)
- Lauren Dunn
- Department of Neurology, Ochsner Health System, New Orleans, LA
| | - Yan Wang
- Department of Neurology, Washington University School of Medicine, St. Louis, MO
| | | | - David Chiu
- Department of Neurology, Houston Methodist Hospital, Houston, TX
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6
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Zarrinkoob L, Myrnäs S, Wåhlin A, Eklund A, Malm J. Cerebral Blood Flow Patterns in Patients With Low-Flow Carotid Artery Stenosis, a 4D-PCMRI Assessment. J Magn Reson Imaging 2024. [PMID: 38168876 DOI: 10.1002/jmri.29216] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/16/2023] [Accepted: 12/18/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND Compromised cerebral blood flow can contribute to future ischemic events in patients with symptomatic carotid artery disease. However, there is limited knowledge of the effects on cerebral hemodynamics resulting from a reduced internal carotid artery (ICA) blood flow rate (BFR). PURPOSE Investigate how reduced ICA-BFR, relates to BFR in the cerebral arteries. STUDY TYPE Prospective. SUBJECTS Thirty-eight patients, age 72 ± 6 years (11 female). FIELD STRENGTH/SEQUENCE 3-Tesla, four-dimensional phase-contrast magnetic resonance imaging (4D-PCMRI). ASSESSMENT Patients with ischemic stroke or transient ischemic attack were evaluated regarding the degree of stenosis. 4D-PCMRI was used to measure cerebral BFR in 38 patients with symptomatic carotid stenosis (≥50%). BFR in the cerebral arteries was assessed in two subgroups based on symptomatic ICA-BFR: reduced ICA-flow (<160 mL/minutes) and preserved ICA-flow (≥160 mL/minutes). BFR laterality was defined as a difference in the paired ipsilateral-contralateral arteries. STATISTICAL TESTS Patients were grouped based on ICA-BFR (reduced vs. preserved). Statistical tests (independent sample t-test/paired t-test) were used to compare groups and hemispheres. Significance was determined at P < 0.05. RESULTS The degree of stenosis was not significantly different, 80% (95% confidence interval [CI] = 73%-87%) in the reduced ICA-flow vs. 72% (CI = 66%-76%) in the preserved ICA-flow; P = 0.09. In the reduced ICA-flow group, a significantly reduced BFR was found in the ipsilateral middle cerebral artery and anterior cerebral artery (A1), while significantly increased in the contralateral A1. Retrograde BFR was found in the posterior communicating artery and ophthalmic artery. Significant BFR laterality was present in all paired arteries in the reduced ICA-flow group, contrasting the preserved ICA-flow group (P = 0.14-0.93). DATA CONCLUSIONS 4D-PCMRI revealed compromised cerebral BFR due to carotid stenosis, not possible to detect by solely analyzing the degree of stenosis. In patients with reduced ICA-flow, collaterals were not sufficient to maintain symmetrical BFR distribution to the two hemispheres. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 3.
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Affiliation(s)
- Laleh Zarrinkoob
- Department of Surgical and Perioperative Sciences, Anesthesiology and Intensive Care Medicine Unit, Umeå University, Umeå, Sweden
| | - Sanne Myrnäs
- Department of Surgical and Perioperative Sciences, Anesthesiology and Intensive Care Medicine Unit, Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Biomedical Engineering, Umeå University, Umeå, Sweden
- Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
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Laviv Y, Saraf D, Oxman L, Zvi IB. Supratentorial hemangioblastoma: correlation between phenotype, gender and vascular territory affected. Neurosurg Rev 2023; 46:281. [PMID: 37875641 DOI: 10.1007/s10143-023-02194-y] [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] [Received: 07/22/2023] [Revised: 09/17/2023] [Accepted: 10/19/2023] [Indexed: 10/26/2023]
Abstract
Supratentorial hemangioblastomas are rare, vascular lesions. The presence of peri-tumoral cysts and edema has meaningful clinical, diagnostic and therapeutic implications. Nevertheless, the pathogenesis of both cyst and edema formation is not fully understood. This study sought to determine if the radiologic phenotype of supratentorial hemangioblastoma is affected by the different cerebral arterial circulations. Review of the English-language literature from 1973 to 2023 yielded 53 cases of parenchymal supratentorial hemangioblastomas eligible for analysis. Patients were divided by the vascular territorial distribution of the lesions: anterior circulation (n = 36) or posterior circulation (n = 17), and the groups were compared for demographic, clinical, radiologic and molecular variables. Univariate analyses yielded a significant difference between the groups in five variables. Cystic changes and "classic" radiological phenotype were associated with hemangioblastomas of the posterior circulation (OR = 0.19, p = 0.045 and OR = 0.287, p = 0.048, respectively), while female gender, significant peritumoral edema and purely solid phenotype were associated with hemangioblastomas of the anterior circulation (OR = 3.384, p = 0.045 and OR = 5.25, p = 0.05 and OR = 14.0, p = 0.015; respectively). On multivariate analysis, solid phenotype and female gender remained significantly associated with the anterior circulation (OR = 36.04, p = 0.014 and OR = 4.45, p = 0.045). The incidence of von-Hippel Lindau disease was higher in the anterior-circulation group. Cystic tumors were present in all females in the posterior-circulation group compared to 43.4% in the anterior-circulation group (OR = 20.714, 95% CI 1.061 to 404.122; p = 0.045). Based on historical cases of supratentorial hemangioblastoma, this study shows that different tumor phenotypes are associated with the different cerebral circulations. Gender was also associated with differences in tumor distribution and radiologic phenotype. These novel data may improve our understanding of unique vascular diseases of the central nervous system.
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Affiliation(s)
- Yosef Laviv
- Department of Neurosurgery, Rabin Medical Center - Beilinson Hospital, Petach Tikva, Israel.
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
| | - David Saraf
- Department of Neurosurgery, Rabin Medical Center - Beilinson Hospital, Petach Tikva, Israel
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Liat Oxman
- Department of Neurosurgery, Rabin Medical Center - Beilinson Hospital, Petach Tikva, Israel
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ido Ben Zvi
- Department of Neurosurgery, Rabin Medical Center - Beilinson Hospital, Petach Tikva, Israel
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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Straccia A, Chassagne F, Bass DI, Barros G, Leotta DF, Sheehan F, Sharma D, Levitt MR, Aliseda A. A Novel Patient-Specific Computational Fluid Dynamics Study of the Activation of Primary Collateral Pathways in the Circle of Willis During Vasospasm. J Biomech Eng 2023; 145:041008. [PMID: 36173034 PMCID: PMC9791673 DOI: 10.1115/1.4055813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 09/17/2022] [Indexed: 12/30/2022]
Abstract
The Circle of Willis (CoW) is a redundant network of blood vessels that perfuses the brain. The ringlike anatomy mitigates the negative effects of stroke by activating collateral pathways that help maintain physiological perfusion. Previous studies have investigated the activation of these pathways during embolic stroke and internal carotid artery occlusion. However, the role of collateral pathways during cerebral vasospasm-an involuntary constriction of blood vessels after subarachnoid hemorrhage-is not well-documented. This study presents a novel technique to create patient-specific computational fluid dynamics (CFD) simulations of the Circle of Willis before and during vasospasm. Computed tomographic angiography (CTA) scans are segmented to model the vasculature, and transcranial Doppler ultrasound (TCD) measurements of blood flow velocity are applied as boundary conditions. Bayesian analysis leverages information about the uncertainty in the measurements of vessel diameters and velocities to find an optimized parameter set that satisfies mass conservation and that is applied in the final simulation. With this optimized parameter set, the diameters, velocities, and flow rates fall within typical literature values. Virtual angiograms modeled using passive scalar transport agree closely with clinical angiography. A sensitivity analysis quantifies the changes in collateral flow rates with respect to changes in the inlet and outlet flow rates. This analysis can be applied in the future to a cohort of patients to investigate the relationship between the locations and severities of vasospasm, the patient-to-patient anatomical variability in the Circle of Willis, and the activation of collateral pathways.
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Affiliation(s)
- Angela Straccia
- Department of Mechanical Engineering, University of Washington, 3900 E Stevens Way NE, Seattle, WA 98195
| | - Fanette Chassagne
- INSERM U1059 Sainboise, Mines Saint-Étienne, 158 cours Fauriel, Saint-Étienne 42000, France
| | - David I. Bass
- Department of Neurological Surgery, University of Washington, 325 Ninth Avenue, Box 359924, Seattle, WA 98104
| | - Guilherme Barros
- Department of Neurological Surgery, University of Washington, 325 Ninth Avenue, Box 359924, Seattle, WA 98104
| | - Daniel F. Leotta
- Applied Physics Laboratory, University of Washington, 1013 NE 40th 28 St, Box 355640, Seattle, WA 98105
| | - Florence Sheehan
- Department of Medicine, University of Washington, 1959 NE Pacific St, RR-616, Seattle, WA 98195
| | - Deepak Sharma
- Department of Neurological Surgery, University of Washington, 325 Ninth Avenue, Box 359924, Seattle, WA 98104
| | - Michael R. Levitt
- Department of Neurological Surgery, University of Washington, 325 Ninth Avenue, Box 359924, Seattle, WA 98104; Department of Mechanical Engineering, University of Washington, 3900 E Stevens Way NE, Seattle, WA 98195; Department of Radiology, University of Washington, 325 Ninth Avenue, Box 359924, Seattle, WA 98104
| | - Alberto Aliseda
- Department of Mechanical Engineering, University of Washington, 3900 E Stevens Way NE, Seattle, WA 98195; Department of Neurological Surgery, University of Washington, 325 Ninth Avenue, Box 359924, Seattle, WA 98104
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Bozzetto M, Soliveri L, Volpi J, Remuzzi A, Barbieri A, Lanterna LAA, Lanzarone E. Computational fluid dynamic modeling of flow-altering surgical procedures: feasibility assessment on saccular aneurysm case study. COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING: IMAGING & VISUALIZATION 2022. [DOI: 10.1080/21681163.2022.2140310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Michela Bozzetto
- Laboratory of Medical Imaging, Istituto di Ricerche Famacologiche “Mario Negri” IRCCS, Ranica, Italy
| | - Luca Soliveri
- Laboratory of Medical Imaging, Istituto di Ricerche Famacologiche “Mario Negri” IRCCS, Ranica, Italy
| | - Jessica Volpi
- Department of Management, Information and Production and Engineering, University of Bergamo, Dalmine, Italy
| | - Andrea Remuzzi
- Department of Management, Information and Production and Engineering, University of Bergamo, Dalmine, Italy
| | - Antonio Barbieri
- Department of Neurosurgery, San Carlo Borromeo Hospital, Milan, Italy
| | | | - Ettore Lanzarone
- Department of Management, Information and Production and Engineering, University of Bergamo, Dalmine, Italy
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Challenges in Modeling Hemodynamics in Cerebral Aneurysms Related to Arteriovenous Malformations. Cardiovasc Eng Technol 2022; 13:673-684. [PMID: 35106721 DOI: 10.1007/s13239-022-00609-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 01/07/2022] [Indexed: 01/27/2023]
Abstract
PURPOSE The significantly higher incidence of aneurysms in patients with arteriovenous malformations (AVMs) suggests a strong hemodynamic relationship between these lesions. The presence of an AVM alters hemodynamics in proximal vessels by drastically changing the distal resistance, thus affecting intra-aneurysmal flow. This study discusses the challenges associated with patient-specific modeling of aneurysms in the presence of AVMs. METHODS We explore how the presence of a generic distal AVM affects upstream aneurysms by examining the relationship between distal resistance and aneurysmal wall shear stress using physiologically realistic estimates for the influence of the AVM on hemodynamics. Using image-based computational models of aneurysms and surrounding vasculature, aneurysmal wall-shear stress is calculated for a range of distal resistances corresponding to the presence of AVMs of various sizes and compared with a control case representing the absence of an AVM. RESULTS In the patient cases considered, the alteration in aneurysmal wall shear stress due to the presence of an AVM is considerable, as much as 19 times the base case wall shear stress. Furthermore, the relationship between aneurysmal wall shear stress and distal resistance is shown to be highly geometry-dependent and nonlinear. In most cases, the range of physiologically realistic possibilities for AVM-related distal resistance are so large that patient-specific flow measurements are necessary for meaningful predictions of wall shear stress. CONCLUSIONS The presented work offers insight on the impact of distal AVMs on aneurysmal wall shear stress using physiologically realistic computational models. Patient-specific modeling of hemodynamics in aneurysms and associated AVMs has great potential for understanding lesion pathogenesis, surgical planning, and assessing the effect of treatment of one lesion relative to another. However, we show that modeling approaches cannot usually meaningfully quantify the impact of AVMs if based solely on imaging data from CT and X-ray angiography, currently used in clinical practice. Based on recent studies, it appears that 4D flow MRI is one promising approach to obtaining meaningful patient-specific flow boundary conditions that improve modeling fidelity.
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11
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Hatakeyama N, Kobayashi S. Development and practical evaluation of a saturation effect learning simulator for inflow magnetic resonance angiography. Radiol Phys Technol 2022; 15:311-322. [PMID: 36002782 DOI: 10.1007/s12194-022-00671-5] [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] [Received: 01/20/2022] [Revised: 08/05/2022] [Accepted: 08/06/2022] [Indexed: 11/25/2022]
Abstract
The quality of visualization in inflow magnetic resonance angiography (MRA) depends highly on the excitation state of the longitudinal magnetization obtained using specified imaging parameters. In addition, signal intensity changes controlled by the preparation pulse-such as inversion recovery (IR) and saturation recovery (SR)-can potentially be used as quantitative physiological values. Although having practitioners understand these relationships both qualitatively and quantitatively is important, handling clinical equipment in practical learning or experiments involves limited opportunities. The simulator corresponds to a three-dimensional spoiled gradient echo sequence and allows users to freely input multiple virtual excitation effects in space and time. The purpose of this study was to quantitatively evaluate the agreement between the measured MRAs obtained in flow phantom tests and virtual MRAs simulated under similar conditions. We imaged two vascular flow phantoms on a 3.0 T MR system using three-dimensional (3D) time-of-flight (TOF) MRA and 3D inversion recovery tissue signal suppression (IR-suppression) MRA protocols. We evaluated quantitative values for consistency between the measured and virtual MRAs images with matched spatial resolution. Then we assessed the coincidence by reformatting maximum-intensity projection images with 1 mm isotropic pixels, with it ranging from 89.6 to 92.0% and 89.1 to 92.9% for TOF MRA and IR-suppression MRA, respectively. These results may be useful as a reference index for the theoretical study of MRA images by practitioners, for complementary validation by phantom testing, or for the development of MRI-related simulators.
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Affiliation(s)
- Norishige Hatakeyama
- Nagano Chuo Hospital, 1570 Nishi-Tsuruga, Nagano, 380-0814, Japan.
- Graduate School of Medicine, Science and Technology, Shinshu University, Matsumoto, Japan.
| | - Shunichi Kobayashi
- Graduate School of Medicine, Science and Technology, Shinshu University, Matsumoto, Japan
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12
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Khang M, Bindra RS, Mark Saltzman W. Intrathecal delivery and its applications in leptomeningeal disease. Adv Drug Deliv Rev 2022; 186:114338. [PMID: 35561835 DOI: 10.1016/j.addr.2022.114338] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 04/26/2022] [Accepted: 05/06/2022] [Indexed: 12/22/2022]
Abstract
Intrathecal delivery (IT) of opiates into the cerebrospinal fluid (CSF) for anesthesia and pain relief has been used clinically for decades, but this relatively straightforward approach of bypassing the blood-brain barrier has been underutilized for other indications because of its lack of utility in delivering small lipid-soluble drugs. However, emerging evidence suggests that IT drug delivery be an efficacious strategy for the treatment of cancers in which there is leptomeningeal spread of disease. In this review, we discuss CSF flow dynamics and CSF clearance pathways in the context of intrathecal delivery. We discuss human and animal studies of several new classes of therapeutic agents-cellular, protein, nucleic acid, and nanoparticle-based small molecules-that may benefit from IT delivery. The complexity of the CSF compartment presents several key challenges in predicting biodistribution of IT-delivered drugs. New approaches and strategies are needed that can overcome the high rates of turnover in the CSF to reach specific tissues or cellular targets.
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13
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Saba L, Antignani PL, Gupta A, Cau R, Paraskevas KI, Poredos P, Wasserman B, Kamel H, Avgerinos ED, Salgado R, Caobelli F, Aluigi L, Savastano L, Brown M, Hatsukami T, Hussein E, Suri JS, Mansilha A, Wintermark M, Staub D, Montequin JF, Rodriguez RTT, Balu N, Pitha J, Kooi ME, Lal BK, Spence JD, Lanzino G, Marcus HS, Mancini M, Chaturvedi S, Blinc A. International Union of Angiology (IUA) consensus paper on imaging strategies in atherosclerotic carotid artery imaging: From basic strategies to advanced approaches. Atherosclerosis 2022; 354:23-40. [DOI: 10.1016/j.atherosclerosis.2022.06.1014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 06/10/2022] [Accepted: 06/14/2022] [Indexed: 12/24/2022]
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14
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Cerebral Arterial Asymmetries in the Neonate: Insight into the Pathogenesis of Stroke. Symmetry (Basel) 2022. [DOI: 10.3390/sym14030456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Neonatal and adult strokes are more common in the left than in the right cerebral hemisphere in the middle cerebral arterial territory, and adult extracranial and intracranial vessels are systematically left-dominant. The aim of the research reported here was to determine whether the asymmetric vascular ground plan found in adults was present in healthy term neonates (n = 97). A new transcranial Doppler ultrasonography dual-view scanning protocol, with concurrent B-flow and pulsed wave imaging, acquired multivariate data on the neonatal middle cerebral arterial structure and function. This study documents for the first-time systematic asymmetries in the middle cerebral artery origin and distal trunk of healthy term neonates and identifies commensurately asymmetric hemodynamic vulnerabilities. A systematic leftward arterial dominance was found in the arterial caliber and cortically directed blood flow. The endothelial wall shear stress was also asymmetric across the midline and varied according to vessels’ geometry. We conclude that the arterial structure and blood supply in the brain are laterally asymmetric in newborns. Unfavorable shearing forces, which are a by-product of the arterial asymmetries described here, might contribute to a greater risk of cerebrovascular pathology in the left hemisphere.
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15
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Donà C, Koschutnik M, Nitsche C, Winter MP, Seidl V, Siller-Matula J, Mach M, Andreas M, Bartko P, Kammerlander AA, Goliasch G, Lang I, Hengstenberg C, Mascherbauer J. Cerebral Protection in TAVR-Can We Do Without? A Real-World All-Comer Intention-to-Treat Study-Impact on Stroke Rate, Length of Hospital Stay, and Twelve-Month Mortality. J Pers Med 2022; 12:jpm12020320. [PMID: 35207808 PMCID: PMC8878932 DOI: 10.3390/jpm12020320] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/25/2022] [Accepted: 02/03/2022] [Indexed: 12/03/2022] Open
Abstract
Background: Stroke associated with transcatheter aortic valve replacement (TAVR) is a potentially devastating complication. Until recently, the Sentinel™ Cerebral Protection System (CPS; Boston Scientific, Marlborough, MA, USA) has been the only commercially available device for mechanical prevention of TAVR-related stroke. However, its effectiveness is still undetermined. Objectives: To explore the impact of Sentinel™ on stroke rate, length of hospital stay (LOS), and twelve-month mortality in a single-center, real-world, all-comers TAVR cohort. Material and Methods: Between January 2019 and August 2020 consecutive patients were assigned to TAVR with or without Sentinel™ in a 1:1 fashion according to the treating operator. We defined as primary endpoint clinically detectable cerebrovascular events within 72 h after TAVR and as secondary endpoints LOS and 12-month mortality. Logistic and linear regression analyses were used to assess associations of Sentinel™ use with endpoints. Results: Of 411 patients (80 ± 7 y/o, 47.4% female, EuroSCORE II 6.3 ± 5.9%), Sentinel™ was used in 213 (51.8%), with both filters correctly deployed in 189 (46.0%). Twenty (4.9%) cerebrovascular events were recorded, ten (2.4%) of which were disabling strokes. Patients with Sentinel™ suffered 71% less (univariate analysis; OR 0.29, 95%CI 0.11–0.82; p = 0.02) and, respectively, 76% less (multivariate analysis; OR 0.24, 95%CI 0.08–0.76; p = 0.02) cerebrovascular events compared to patients without Sentinel™. Sentinel™ use was also significantly associated with shorter LOS (Regression coefficient −2.47, 95%CI −4.08, −0.87; p < 0.01) and lower 12-month all-cause mortality (OR 0.45; 95%CI 0.22–0.93; p = 0.03). Conclusion: In the present prospective all-comers TAVR cohort, patients with Sentinel™ use showed (1) lower rates of cerebrovascular events, (2) shortened LOS, and (3) improved 12-month survival. These data promote the use of a CPS when implanting TAVR valves.
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Affiliation(s)
- Carolina Donà
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Matthias Koschutnik
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Christian Nitsche
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Max-Paul Winter
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Veronika Seidl
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Jolanta Siller-Matula
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Markus Mach
- Department of Cardiac Surgery, Medical University of Vienna, 1090 Vienna, Austria; (M.M.); (M.A.)
| | - Martin Andreas
- Department of Cardiac Surgery, Medical University of Vienna, 1090 Vienna, Austria; (M.M.); (M.A.)
| | - Philipp Bartko
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Andreas Anselm Kammerlander
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
- Cardiovascular Imaging Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Georg Goliasch
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Irene Lang
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Christian Hengstenberg
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
| | - Julia Mascherbauer
- Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, 1090 Vienna, Austria; (C.D.); (M.K.); (C.N.); (M.-P.W.); (V.S.); (J.S.-M.); (P.B.); (A.A.K.); (G.G.); (I.L.); (C.H.)
- Department of Internal Medicine 3, University Hospital St. Poelten, Karl Landsteiner University of Health Sciences, 3500 Krems, Austria
- Correspondence: ; Tel.: +43-1-40400-46140; Fax: +43-1-40400-42160
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16
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Ballout AA, Libman RB, Schneider JR, Black K, Sideras P, Wang JJ, White TG, Dehdashti AR, Woo HH, Katz JM. Vertebrobasilar Stroke: Association Between Infarction Patterns and Quantitative Magnetic Resonance Angiography Flow State. J Am Heart Assoc 2022; 11:e023991. [PMID: 35170987 PMCID: PMC9075089 DOI: 10.1161/jaha.121.023991] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Background Treatment and prognosis of vertebrobasilar atherosclerotic disease differs depending on stroke mechanism, such as artery‐to‐artery embolism, branch atheromatous disease, and hemodynamic ischemia. Our aim was to investigate the relationship between infarction pattern and flow status using quantitative magnetic resonance angiography (QMRA), to determine the validity of using infarction patterns to infer stroke mechanism. Methods and Results This is a retrospective study of patients with ischemic stroke with intra‐ or extracranial vertebrobasilar atherosclerotic stenosis, who underwent magnetic resonance imaging of the brain, neurovascular imaging, and QMRA, between 2009 and 2021. Patients with cerebral infarction predating or following QMRA by ≥1 year, or QMRA studies performed for basilar thrombosis, vertebral dissection, or only postangioplasty/stenting, were excluded. Poststenotic flow (basilar and posterior cerebral arteries) was dichotomized as low‐flow or normal‐flow based on published criteria. Of 1211 consecutive patients who underwent QMRA noninvasive optimal analysis, 69 met inclusion. Mixed patterns were most common (46.4%), followed by perforator (23.2%), borderzone (14.5%), and territorial (15.9%). Patients with low‐flow had a significantly higher rate of borderzone+ patterns (borderzone alone or in mixed pattern) compared with patients with normal‐flow (77.4% low‐flow versus 39.5% normal‐flow, P=0.002). Borderzone+ patterns were associated with 61.5% probability of low‐flow state, while no borderzone (perforator/territorial) patterns were associated with 76.7% probability of normal‐flow state. Conclusions Borderzone infarction pattern (alone or mixed) was associated with low poststenotic posterior circulation flow by QMRA. However, borderzone pattern only moderately predicted low‐flow state, and may be an unreliable flow marker. Therefore, infarct topography may complement, but should not replace hemodynamic studies to establish flow status.
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Affiliation(s)
- Ahmad A Ballout
- Department of Neurology Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
| | - Richard B Libman
- Department of Neurology Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
| | - Julia R Schneider
- Department of Neurology Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
| | - Karen Black
- Department of Radiology Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
| | - Panagiotis Sideras
- Department of Radiology Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
| | - Jason J Wang
- Department of Radiology Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
| | - Timothy G White
- Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
| | - Amir R Dehdashti
- Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
| | - Henry H Woo
- Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
| | - Jeffrey M Katz
- Department of Neurology Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY.,Department of Radiology Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset NY
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17
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Kim SJ, Schneider DJ, Feldmann E, Liebeskind DS. Intracranial atherosclerosis: Review of imaging features and advances in diagnostics. Int J Stroke 2022; 17:599-607. [PMID: 34983259 DOI: 10.1177/17474930211066427] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Intracranial atherosclerotic disease is one of the leading causes of ischemic strokes and poses a moderate risk of recurrence. Diagnosis is currently limited to stenosis on luminal imaging, which likely underestimates the true prevalence of the disease. Detection of non-stenosing intracranial atherosclerosis is important in order to optimize secondary stroke prevention strategies. This review collates findings from the early seminal trials and the latest studies in advanced radiological techniques that characterize symptomatic intracranial atherosclerotic disease across various imaging modalities. While computed tomography angiography (CTA) and magnetic resonance angiography (MRA) comprise diagnostic mainstays in identifying stenotic changes secondary to atherosclerosis, emerging techniques such as high-resolution MRA, quantitative MRA, and computational fluid dynamics may reveal a myriad of other underlying pathophysiological mechanisms.
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Affiliation(s)
- Song J Kim
- Vascular Neurology and Neurocritical Care, Sutter Health Comprehensive Stroke Care Center, San Francisco, CA, USA
| | - David J Schneider
- Cardiovascular Research Institute of Vermont, The University of Vermont, Colchester, VT, USA
| | - Edward Feldmann
- Neurosciences and Rehabilitation, Baystate Health, Springfield, MA, USA
| | - David S Liebeskind
- Neurovascular Imaging Research Core and UCLA Stroke Center, Los Angeles, CA, USA
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18
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Koktzoglou I, Huang R, Edelman RR. Quantitative time-of-flight MR angiography for simultaneous luminal and hemodynamic evaluation of the intracranial arteries. Magn Reson Med 2022; 87:150-162. [PMID: 34374455 PMCID: PMC8616782 DOI: 10.1002/mrm.28969] [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: 04/15/2021] [Revised: 07/19/2021] [Accepted: 07/25/2021] [Indexed: 01/03/2023]
Abstract
PURPOSE To report a quantitative time-of-flight (qTOF) MRA technique for simultaneous luminal and hemodynamic evaluation of the intracranial arteries. METHODS Implemented using a thin overlapping slab 3D stack-of-stars based 3-echo FLASH readout, qTOF was tested in a flow phantom and for imaging the intracranial arteries of 10 human subjects at 3 Tesla. Display of the intracranial arteries with qTOF was compared to resolution-matched and scan time-matched standard Cartesian 3D time-of-flight (TOF) MRA, whereas quantification of mean blood flow velocity with qTOF, done using a computer vision-based inter-echo image analysis procedure, was compared to 3D phase contrast MRA. Arterial-to-background contrast-to-noise ratio was measured, and intraclass correlation coefficient was used to evaluate agreement of flow velocities. RESULTS For resolution-matched protocols of similar scan time, qTOF portrayed the intracranial arteries with good morphological correlation with standard Cartesian TOF, and both techniques provided superior contrast-to-noise ratio and arterial delineation compared to phase contrast (20.6 ± 3.0 and 37.8 ± 8.7 vs. 11.5 ± 2.2, P < .001, both comparisons). With respect to phase contrast, qTOF showed excellent agreement for measuring mean flow velocity in the flow phantom (intraclass correlation coefficient = 0.981, P < .001) and good agreement in the intracranial arteries (intraclass correlation coefficient = 0.700, P < .001). Stack-of-stars data sampling used with qTOF eliminated oblique in-plane flow misregistration artifacts that were seen with standard Cartesian TOF. CONCLUSION qTOF is a new 3D MRA technique for simultaneous luminal and hemodynamic evaluation of the intracranial arteries that provides significantly greater contrast-to-noise ratio efficiency than phase contrast and eliminates misregistration artifacts from oblique in-plane blood flow that occur with standard 3D TOF.
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Affiliation(s)
- Ioannis Koktzoglou
- Department of Radiology, NorthShore University HealthSystem, Evanston, IL,Pritzker School of Medicine, University of Chicago, Chicago, IL
| | - Rong Huang
- Department of Radiology, NorthShore University HealthSystem, Evanston, IL
| | - Robert R. Edelman
- Department of Radiology, NorthShore University HealthSystem, Evanston, IL,Northwestern University Feinberg School of Medicine, Chicago, IL
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19
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Miller ML, Ghisletta P, Jacobs BS, Dahle CL, Raz N. Changes in cerebral arterial pulsatility and hippocampal volume: a transcranial doppler ultrasonography study. Neurobiol Aging 2021; 108:110-121. [PMID: 34555677 DOI: 10.1016/j.neurobiolaging.2021.08.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 08/06/2021] [Accepted: 08/19/2021] [Indexed: 11/16/2022]
Abstract
The physiological mechanisms of age-related cognitive decline remain unclear, in no small part due to the lack of longitudinal studies. Extant longitudinal studies focused on gross neuroanatomy and diffusion properties of the brain. We present herein a longitudinal analysis of changes in arterial pulsatility - a proxy for arterial stiffness - in two major cerebral arteries, middle cerebral and vertebral. We found that pulsatility increased in some participants over a relatively short period and these increases were associated with hippocampal shrinkage. Higher baseline pulsatility was associated with lower scores on a test of fluid intelligence at follow-up. This is the first longitudinal evidence of an association between increase in cerebral arterial stiffness over time and regional shrinkage.
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Affiliation(s)
| | - Paolo Ghisletta
- Université de Genève, FPSE, Genève GE, Switzerland; UniMail, Swiss National Centre of Competence in Research LIVES, Genève GE, Switzerland; UniDistance Suisse, Brig VS, Switzerland
| | - Bradley S Jacobs
- Wright State University, Department of Internal Medicine and Neurology, Dayton, Ohio
| | - Cheryl L Dahle
- Wayne State University, Institute of Gerontology, Detroit, Michigan
| | - Naftali Raz
- Wayne State University, Institute of Gerontology, Detroit, Michigan; Wayne State University, Department of Psychology, Detroit, Michigan; Max Planck Institute for Human Development, Berlin-Dahlem, Germany
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20
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Cattaneo GF, Herrmann AM, Eiden SA, Wieser M, Kellner E, Doostkam S, Süß P, Kiefer S, Fauth L, Maurer CJ, Wolfertz J, Nitzsche B, Büchert M, Jost T, Ihorst G, Haberstroh J, Mülling C, Strecker C, Niesen WD, Shah MJ, Urbach H, Boltze J, Meckel S. Selective intra-carotid blood cooling in acute ischemic stroke: A safety and feasibility study in an ovine stroke model. J Cereb Blood Flow Metab 2021; 41:3097-3110. [PMID: 34159825 PMCID: PMC8756475 DOI: 10.1177/0271678x211024952] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Selective therapeutic hypothermia (TH) showed promising preclinical results as a neuroprotective strategy in acute ischemic stroke. We aimed to assess safety and feasibility of an intracarotid cooling catheter conceived for fast and selective brain cooling during endovascular thrombectomy in an ovine stroke model.Transient middle cerebral artery occlusion (MCAO, 3 h) was performed in 20 sheep. In the hypothermia group (n = 10), selective TH was initiated 20 minutes before recanalization, and was maintained for another 3 h. In the normothermia control group (n = 10), a standard 8 French catheter was used instead. Primary endpoints were intranasal cooling performance (feasibility) plus vessel patency assessed by digital subtraction angiography and carotid artery wall integrity (histopathology, both safety). Secondary endpoints were neurological outcome and infarct volumes.Computed tomography perfusion demonstrated MCA territory hypoperfusion during MCAO in both groups. Intranasal temperature decreased by 1.1 °C/3.1 °C after 10/60 minutes in the TH group and 0.3 °C/0.4 °C in the normothermia group (p < 0.001). Carotid artery and branching vessel patency as well as carotid wall integrity was indifferent between groups. Infarct volumes (p = 0.74) and neurological outcome (p = 0.82) were similar in both groups.Selective TH was feasible and safe. However, a larger number of subjects might be required to demonstrate efficacy.
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Affiliation(s)
- Giorgio Fm Cattaneo
- Institute for Biomedical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Andrea M Herrmann
- Faculty of Veterinary Medicine, Institute of Veterinary Anatomy, Histology and Embryology, Leipzig University, Leipzig, Germany.,Department of Neuroradiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sebastian A Eiden
- Department of Neuroradiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Manuela Wieser
- Department of Neuroradiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Elias Kellner
- Department of MR Physics, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Soroush Doostkam
- Department of Neuropathology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Patrick Süß
- Department of Neuropathology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Selina Kiefer
- Department of Pathology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Lisa Fauth
- Department of Pathology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christoph J Maurer
- Department of Diagnostic and Interventional Radiology and Neuroradiology, Universitätsklinikum Augsburg, Augsburg, Germany
| | | | - Björn Nitzsche
- Faculty of Veterinary Medicine, Institute of Veterinary Anatomy, Histology and Embryology, Leipzig University, Leipzig, Germany
| | | | | | - Gabriele Ihorst
- Department of Clinical Trials, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jörg Haberstroh
- Center for Experimental Models and Transgenic Service (CEMT), Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christoph Mülling
- Faculty of Veterinary Medicine, Institute of Veterinary Anatomy, Histology and Embryology, Leipzig University, Leipzig, Germany
| | - Christoph Strecker
- Department of Neurology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Wolf-Dirk Niesen
- Department of Neurology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Mukesch J Shah
- Department of Neurosurgery, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Horst Urbach
- Department of Neuroradiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Johannes Boltze
- School of Live Sciences, University of Warwick, Coventry, UK
| | - Stephan Meckel
- Department of Neuroradiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Institute of Neuroradiology, Kepler University Hospital, Johannes Kepler University Linz, Austria
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21
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Prediction of atherosclerotic changes in cavernous carotid aneurysms based on computational fluid dynamics analysis: a proof-of-concept study. Neuroradiology 2021; 64:575-585. [PMID: 34505180 DOI: 10.1007/s00234-021-02803-x] [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: 05/03/2021] [Accepted: 09/01/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE Recent computational fluid dynamics (CFD) studies have demonstrated the concurrence of atherosclerotic changes in regions exposed to prolonged blood residence. In this proof-of-concept study, we investigated a small but homogeneous cohort of large, cavernous carotid aneurysms (CCAs) to establish the clinical feasibility of CFD analysis in treatment planning, based on the association between pathophysiology and hemodynamics. METHODS This study included 15 patients with individual large CCAs. We identified calcifications, which indicated atherosclerotic changes, using the masking data of digital subtraction angiography. We conducted a CFD simulation under patient-specific inlet flow rates measured using magnetic resonance (MR) velocimetry. In the post-CFD analysis, we calculated the blood residence time ([Formula: see text]) and segmented the surface exposed to blood residence time over 1 s ([Formula: see text]). We measured the decrease in volume after flow diversion using the original time-of-flight MR angiography data. RESULTS Calcifications were observed in the region with [Formula: see text]. In addition, the ratio of [Formula: see text] to the surface of the aneurysmal domain exhibited a negative relationship with the rate of volume reduction at the 6- and 12-month follow-ups. Post-CFD visualization demonstrated that intra-aneurysmal swirling flow prolonged blood residence time under the condition of a small inlet flow rate, when compared to the aneurysmal volume. CONCLUSION The results of this study suggest the usefulness of CFD analysis for the diagnosis of atherosclerotic changes in large CCAs that may affect the therapeutic response after flow diversion.
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22
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MacDonald ME, Pike GB. MRI of healthy brain aging: A review. NMR IN BIOMEDICINE 2021; 34:e4564. [PMID: 34096114 DOI: 10.1002/nbm.4564] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 05/08/2021] [Accepted: 05/11/2021] [Indexed: 06/12/2023]
Abstract
We present a review of the characterization of healthy brain aging using MRI with an emphasis on morphology, lesions, and quantitative MR parameters. A scope review found 6612 articles encompassing the keywords "Brain Aging" and "Magnetic Resonance"; papers involving functional MRI or not involving imaging of healthy human brain aging were discarded, leaving 2246 articles. We first consider some of the biogerontological mechanisms of aging, and the consequences of aging in terms of cognition and onset of disease. Morphological changes with aging are reviewed for the whole brain, cerebral cortex, white matter, subcortical gray matter, and other individual structures. In general, volume and cortical thickness decline with age, beginning in mid-life. Prevalent silent lesions such as white matter hyperintensities, microbleeds, and lacunar infarcts are also observed with increasing frequency. The literature regarding quantitative MR parameter changes includes T1 , T2 , T2 *, magnetic susceptibility, spectroscopy, magnetization transfer, diffusion, and blood flow. We summarize the findings on how each of these parameters varies with aging. Finally, we examine how the aforementioned techniques have been used for age prediction. While relatively large in scope, we present a comprehensive review that should provide the reader with sound understanding of what MRI has been able to tell us about how the healthy brain ages.
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Affiliation(s)
- M Ethan MacDonald
- Department of Electrical and Software Engineering, University of Calgary, Calgary, Alberta, Canada
- Departments of Radiology and Clinical Neuroscience, University of Calgary, Calgary, Alberta, Canada
- Healthy Brain Aging Laboratory, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - G Bruce Pike
- Departments of Radiology and Clinical Neuroscience, University of Calgary, Calgary, Alberta, Canada
- Healthy Brain Aging Laboratory, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
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23
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Lamooki SR, Tutino VM, Paliwal N, Damiano RJ, Waqas M, Nagesh SSV, Rajabzadeh-Oghaz H, Vakharia K, Siddiqui AH, Meng H. Evaluation of Two Fast Virtual Stenting Algorithms for Intracranial Aneurysm Flow Diversion. Curr Neurovasc Res 2021; 17:58-70. [PMID: 31987021 DOI: 10.2174/1567202617666200120141608] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 11/13/2019] [Accepted: 11/25/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Endovascular treatment of intracranial aneurysms (IAs) by flow diverter (FD) stents depends on flow modification. Patient-specific modeling of FD deployment and computational fluid dynamics (CFD) could enable a priori endovascular strategy optimization. We developed a fast, simplistic, expansion-free balls-weeping algorithm to model FDs in patientspecific aneurysm geometry. However, since such strong simplification could result in less accurate simulations, we also developed a fast virtual stenting workflow (VSW) that explicitly models stent expansion using pseudo-physical forces. METHODS To test which of these two fast algorithms more accurately simulates real FDs, we applied them to virtually treat three representative patient-specific IAs. We deployed Pipeline Embolization Device into 3 patient-specific silicone aneurysm phantoms and simulated the treatments using both balls-weeping and VSW algorithms in computational aneurysm models. We then compared the virtually deployed FD stents against experimental results in terms of geometry and post-treatment flow fields. For stent geometry, we evaluated gross configurations and porosity. For post-treatment aneurysmal flow, we compared CFD results against experimental measurements by particle image velocimetry. RESULTS We found that VSW created more realistic FD deployments than balls-weeping in terms of stent geometry, porosity and pore density. In particular, balls-weeping produced unrealistic FD bulging at the aneurysm neck, and this artifact drastically increased with neck size. Both FD deployment methods resulted in similar flow patterns, but the VSW had less error in flow velocity and inflow rate. CONCLUSION In conclusion, modeling stent expansion is critical for preventing unrealistic bulging effects and thus should be considered in virtual FD deployment algorithms. Also endowed with its high computational efficiency and superior accuracy, the VSW algorithm is a better candidate for implementation into a bedside clinical tool for FD deployment simulation.
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Affiliation(s)
- Saeb R Lamooki
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY, United States.,Department of Mechanical & Aerospace Engineering, University at Buffalo, Buffalo, NY, United States
| | - Vincent M Tutino
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY, United States.,Department of Biomedical Engineering, University at Buffalo, Buffalo, NY, United States.,Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States.,Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
| | - Nikhil Paliwal
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY, United States.,Department of Mechanical & Aerospace Engineering, University at Buffalo, Buffalo, NY, United States
| | - Robert J Damiano
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY, United States.,Department of Mechanical & Aerospace Engineering, University at Buffalo, Buffalo, NY, United States
| | - Muhammad Waqas
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY, United States.,Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
| | - Setlur S V Nagesh
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY, United States.,Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States.,Department of Radiology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
| | - Hamidreza Rajabzadeh-Oghaz
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY, United States.,Department of Mechanical & Aerospace Engineering, University at Buffalo, Buffalo, NY, United States
| | - Kunal Vakharia
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
| | - Adnan H Siddiqui
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY, United States.,Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States.,Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
| | - Hui Meng
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY, United States.,Department of Mechanical & Aerospace Engineering, University at Buffalo, Buffalo, NY, United States.,Department of Biomedical Engineering, University at Buffalo, Buffalo, NY, United States.,Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
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24
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Serulle Y, Khatri D, Sy H, Yerneni S, Langer D, Ortiz R. Use of quantitative magnetic resonance angiography in patients with symptomatic intracranial arterial stenosis who undergo stenting: Presentation of three cases. J Cerebrovasc Endovasc Neurosurg 2021; 23:136-144. [PMID: 34107594 PMCID: PMC8256016 DOI: 10.7461/jcen.2021.e2020.10.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 12/08/2020] [Indexed: 11/23/2022] Open
Abstract
Intracranial atherosclerotic disease (ICAD) is an important cause of ischemic stroke. The etiology of stroke in patients with ICAD could be due to several mechanisms including hypoperfusion, artery-to-artery embolism, and plaque extension over small penetrating artery ostia. Management of symptomatic ICAD includes medical and endovascular management. Quantitative magnetic resonance angiography (MRA) is a technique that allows for non-invasive measurement of large vessel blood flow in the head and neck. Here, we describe procedural and clinical outcomes on three patients who presented with symptomatic ICAD and were treated with angioplasty and stenting. Quantitative MRA was used pre- and post- procedurally to assess the effects of stenting on the intracranial blood flow. Quantitative measures of intracranial blood flow may serve as an additional triage tool in the evaluation of patients with symptomatic ICAD.
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Affiliation(s)
- Yafell Serulle
- Department of Neurosurgery, Lenox Hill Hospital, New York, NY, USA
| | - Deepak Khatri
- Department of Neurosurgery, Lenox Hill Hospital, New York, NY, USA
| | - Heustein Sy
- Department of Neurosurgery, Lenox Hill Hospital, New York, NY, USA
| | | | - David Langer
- Department of Neurosurgery, Lenox Hill Hospital, New York, NY, USA
| | - Rafael Ortiz
- Department of Neurosurgery, Lenox Hill Hospital, New York, NY, USA
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25
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Deng F, Mu C, Yang L, Yi R, Gu M, Li K. The Differentiation in Image Post-processing and 3D Reconstruction During Evaluation of Carotid Plaques From MR and CT Data Sources. Front Physiol 2021; 12:645438. [PMID: 33935800 PMCID: PMC8085352 DOI: 10.3389/fphys.2021.645438] [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: 12/23/2020] [Accepted: 03/22/2021] [Indexed: 12/17/2022] Open
Abstract
Background: Carotid plaque morphology and tissue composition help assess risk stratification of stroke events. Many post-processing image techniques based on CT and MR images have been widely used in related research, such as image segmentation, 3D reconstruction, and computer fluid dynamics. However, the criteria for the 3D numerical model of carotid plaque established by CT and MR angiographic image data remain open to questioning. Method: We accurately duplicated the geometry and simulated it using computer software to make a 3D numerical model. The initial images were obtained by CTA and TOF-MRA. MIMICS (Materialize’s interactive medical image control system) software was used to process the images to generate three-dimensional solid models of blood vessels and plaques. The subsequent output was exported to the ANSYS software to generate finite element simulation results for the further hemodynamic study. Results: The 3D models of carotid plaque of TOF-MRA and CTA were simulated by using computer software. CTA has a high-density resolution for carotid plaque, the boundary of the CTA image is obvious, and the main component of which is a calcified tissue. However, the density resolution of TOF-MRA for the carotid plaque and carotid artery was not as good as that of CTA. The results show that there is a large deviation between the TOF-MRA and CTA 3D model of plaque in the carotid artery due to the unclear recognition of plaque boundary during 3D reconstruction, and this can further affect the simulation results of hemodynamics. Conclusion: In this study, two-dimensional images and three-dimensional models of carotid plaques obtained by two angiographic techniques were compared. The potential of these two imaging methods in clinical diagnosis and fluid dynamics of carotid plaque was evaluated, and the selectivity of image post-processing analysis to original medical image acquisition was revealed.
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Affiliation(s)
| | - Changping Mu
- Department of Radiology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
| | - Ling Yang
- Department of Radiology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
| | - Rongqi Yi
- Department of Radiology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
| | - Min Gu
- Department of Radiology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
| | - Kang Li
- Department of Radiology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
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26
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Identification of intra-individual variation in intracranial arterial flow by MRI and the effect on computed hemodynamic descriptors. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2021; 34:659-666. [PMID: 33839985 DOI: 10.1007/s10334-021-00917-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 02/13/2021] [Accepted: 02/16/2021] [Indexed: 10/21/2022]
Abstract
OBJECTIVES To determine the intra-individual flow variation in serially acquired studies, and the influence of this variation on subsequent hemodynamic simulations using the inlet flow as a boundary condition. Author: Kindly check and confirm whether the corresponding authors are correctly identified.Confirmed. MATERIALS AND METHODS This prospective study included 51 patients (37 females and 14 males) with unruptured intracranial aneurysms who have received more than three times follow-up of 2D phase-contrast MR. The flow and velocity parameters were extracted to calculate the reproducibility and variation. Patient-specific computational fluid dynamics simulations were performed using the measured flows. RESULTS Intraclass correlation coefficients for mean and maximum velocity and flow parameters ranged from 0.77 to 0.90. A 10% CV of mean flow was identified. Variations of 10% in inlet flow resulted in hemodynamic changes including 41.41% of peak systolic wall shear stress; 39.13% of end-diastolic wall shear stress; 2.79% of low shear area at peak systole; 2.12% of low shear area at end diastole: 47.57% of time-averaged wall shear stress; and 0.17% of oscillatory shear index. CONCLUSION This study identified 10% of intra-individual mean flow variation on phase-contrast MR. Intra-individual flow variation resulted in a non-negligible variation in wall shear stress, but relatively small variation in low shear area in hemodynamic calculations.
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27
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Reehal N, Cummings S, Mullen MT, Baker WB, Kung D, Tackett W, Favilla CG. Differentiating Dynamic Cerebral Autoregulation Across Vascular Territories. Front Neurol 2021; 12:653167. [PMID: 33833734 PMCID: PMC8021764 DOI: 10.3389/fneur.2021.653167] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 02/25/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: Transcranial Doppler is commonly used to calculate cerebral autoregulation, but measurements are typically restricted to a single cerebral artery. In exploring topographic heterogeneity, this study reports the first thorough comparison of autoregulation in all major cerebral vessels. Methods: In forty healthy adults, flow velocity was monitored in the anterior, middle, and posterior cerebral arteries, and synchronized with arterial blood pressure. A transfer function analysis provided characteristics of autoregulation by quantifying the relationship between blood pressure and cerebral blood flow velocity. Results: Phase, which quantifies the time course of autoregulation, was similar in all vessels. Gain, which quantifies the magnitude of hemodynamic regulation, was lower in posterior cerebral artery, indicative of tighter regulation. However, after adjusting for baseline flow differences in each vascular territory, normalized gain was similar in all vessels. Conclusions: Discriminating dynamic cerebral autoregulation between cerebrovascular territories is feasible with a transcranial doppler based approach. In the posterior cerebral artery of healthy volunteers, absolute flow is more tightly regulated, but relative flow regulation is consistent across cerebrovascular territories. Significance: The methodology can be applied to focal disease states such as stroke or posterior reversible encephalopathy syndrome, in which the topographic distribution of autoregulation may be particularly critical.
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Affiliation(s)
- Navpreet Reehal
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Stephanie Cummings
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Michael T Mullen
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Wesley B Baker
- Department of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - David Kung
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, United States
| | - William Tackett
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Christopher G Favilla
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
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28
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See AP, Charbel FT. Bypass for flow-augmentation in atherosclerotic carotid occlusion: a review of the literature and career experience. J Neurosurg Sci 2021; 65:305-321. [PMID: 33709658 DOI: 10.23736/s0390-5616.21.05094-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Atherosclerosis of the internal carotid artery and intracranial vessels can compromise cerebral hemodynamics and cause stroke. Cerebral bypass has a half-century history in augmenting or replacing blood flow the brain. Several trials have investigated various applications of cerebral bypass in flow augmentation for atherosclerotic disease. This review discusses the clinical science of cerebrovascular atherosclerosis to provide the context in which cerebral bypass is currently applied. This includes prior clinical trials, ongoing clinical trials, and consensus guidelines, and is complemented by studies in the physiologic science of cerebrovascular flow. The scientific background is supplemented by the description of the technical art of bypass surgery based on a three-decade experience. Successful application of cerebral bypass to augment flow in atherosclerotic cerebrovascular disease requires correct diagnosis of compromised hemodynamic reserve refractory to medical optimization and an appropriate matching of bypass flow with cerebral demand.
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29
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Fiedler J, Reiser M, Košťál P, Kubále J, Ostrý S, Hrbáč T, Kešnerová P, Fadrná T, Langová K, Herzig R, Školoudík D. Blood Flow Volume Measurement in Cervical and Intracranial Arteries using Quantitative Magnetic Resonance Angiography and Duplex Sonography (Bocaccia) - A Prospective Observational Study. ULTRASCHALL IN DER MEDIZIN (STUTTGART, GERMANY : 1980) 2021; 42:65-74. [PMID: 32340045 DOI: 10.1055/a-1113-7343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
PURPOSE Cerebral blood flow volume is an important factor for the accurate diagnosis of neurovascular diseases and treatment indication. This study aims to assess correlations of blood flow volume measurements in cervical and intracranial arteries between duplex sonography and quantitative magnetic resonance angiography (qMRA). MATERIALS AND METHODS Consecutive patients with suspicion of cerebral vascular pathology underwent qMRA and duplex sonography of cervical and intracranial arteries with measurement of blood flow volume in bilateral common (CCA), internal (ICA) and external carotid arteries, vertebral and basilar arteries, middle, anterior, posterior cerebral and posterior communicating arteries using 2 different ultrasound machines. Ten patients underwent all examinations twice. Correlations between blood flow volume measurements were evaluated using Spearman's correlation coefficient and inter-class correlation coefficient (ICC). RESULTS In total, 21 subjects (15 males, mean age: 56.3 ± 6.2 years) were included in the study. Duplex sonography inter-investigator correlation was excellent (ICC = 0.972, p < 0.0001) as well as intra-investigator correlations of both qMRA and duplex sonography (ICC ˃ 0.990, p < 0.0001). Mostly high correlations were recorded between qMRA and duplex sonography in particular cervical arteries but only low to moderate correlations were obtained for intracranial arteries. The mean differences between blood flow volume measurements were 10.9 ± 8.1 % in the CCA and its branches when using qMRA and 15.0 ± 11.9 % when using duplex sonography, 13.5 ± 11.8 %/35.4 ± 34.2 % in the ICA siphon and its branches when using qMRA/duplex sonography, and 24.1 ± 19.7 %/44.9 ± 44.0 % in both vertebral arteries and the basilar artery when using qMRA/duplex sonography. CONCLUSION Duplex sonography as well as qMRA allow for highly reproducible measurement of blood flow volume in cervical and intracranial arteries in routine clinical practice.
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Affiliation(s)
- Jiří Fiedler
- Department of Neurosurgery, Comprehensive Stroke Center, University Hospital Plzeň, Czech Republic
| | - Martin Reiser
- Department of Neurology, Comprehensive Stroke Center, Hospital České Budějovice, Czech Republic
| | - Petr Košťál
- Department of Neurosurgery, Comprehensive Stroke Center, University Hospital Plzeň, Czech Republic
| | - Jiří Kubále
- Department of Radiology, Comprehensive Stroke Center, Hospital České Budějovice, Czech Republic
| | - Svatopluk Ostrý
- Department of Neurology, Comprehensive Stroke Center, Hospital České Budějovice, Czech Republic
| | - Tomáš Hrbáč
- Department of Neurosurgery, Comprehensive Stroke Center, University Hospital Ostrava, Czech Republic
| | - Petra Kešnerová
- Department of Neurology, 2nd Medical Faculty, Charles-University, Praha, Czech Republic
| | - Táňa Fadrná
- Center for Research and Science, Faculty of Health Sciences, Palacký-University Olomouc, Czech Republic
| | - Kateřina Langová
- Department of Biophysics, Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacký-University Olomouc, Czech Republic
| | - Roman Herzig
- Department of Neurology, Comprehensive Stroke Center, Charles-University Faculty of Medicine in Hradec Kralove, Czech Republic
| | - David Školoudík
- Center for Research and Science, Faculty of Health Sciences, Palacký-University Olomouc, Czech Republic
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Miller KB, Gallo SJ, Rivera-Rivera LA, Corkery AT, Howery AJ, Johnson SC, Rowley HA, Wieben O, Barnes JN. Vertebral artery hypoplasia influences age-related differences in blood flow of the large intracranial arteries. AGING BRAIN 2021; 1:100019. [PMID: 36911510 PMCID: PMC9997135 DOI: 10.1016/j.nbas.2021.100019] [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: 12/15/2020] [Revised: 05/26/2021] [Accepted: 06/01/2021] [Indexed: 11/16/2022] Open
Abstract
Our purpose was to compare cerebral blood flow in the large intracranial vessels between healthy adults with (VAH+) and without (No VAH) vertebral artery hypoplasia. We also evaluated age-related differences in regional blood flow through the large cerebral arteries. Healthy young (n = 20; age = 25 ± 3 years) and older adults (n = 19; age = 61 ± 5 years) underwent 4D flow MRI scans to evaluate blood flow in the internal carotid arteries (ICA) and basilar artery (BA). VAH was determined retrospectively from 4D flow MRI using both structural (vessel diameter ≤ 2 mm) and flow criteria (flow ≤ 50 mL/min). We identified 5 young and 5 older adults with unilateral VAH (prevalence = 26%). ICA flow was lower in the VAH+ group compared with the No VAH group (367 ± 75 mL/min vs. 432 ± 92 mL/min, respectively; p < 0.05). There was no difference in BA flow between VAH+ and No VAH (110 ± 20 mL/min vs. 126 ± 40 mL/min, respectively; p = 0.24). When comparing age-related differences in blood flow in the No VAH group, older adults demonstrated lower BA flow compared with young adults (111 ± 38 mL/min vs. 140 ± 38 mL/min, respectively; p < 0.05) but not ICA flow (428 ± 89 mL/min vs. 436 ± 98 mL/min, respectively; p = 0.82). In contrast, in the VAH+ group, older adults had lower ICA flow compared with young adults (312 ± 65 mL/min vs. 421 ± 35 mL/min, respectively; p < 0.01), but not BA flow (104 ± 16 mL/min vs. 117 ± 23 mL/min, respectively; p = 0.32). Our results suggest that the presence of VAH is associated with lower ICA blood flow. Furthermore, VAH may contribute to the variability in the age-related differences in cerebral blood flow in healthy adults.
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Affiliation(s)
- Kathleen B Miller
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin-Madison, Madison, WI, USA
| | - Samuel J Gallo
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin-Madison, Madison, WI, USA
| | - Leonardo A Rivera-Rivera
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.,Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Adam T Corkery
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin-Madison, Madison, WI, USA
| | - Anna J Howery
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin-Madison, Madison, WI, USA
| | - Sterling C Johnson
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.,Geriatric Research Education and Clinical Center, William. S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Howard A Rowley
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.,Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Oliver Wieben
- 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
| | - Jill N Barnes
- Bruno Balke Biodynamics Laboratory, Department of Kinesiology, University of Wisconsin-Madison, Madison, WI, USA
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Romano JG, Prabhakaran S, Nizam A, Feldmann E, Sangha R, Cotsonis G, Campo-Bustillo I, Koch S, Rundek T, Chimowitz MI, Liebeskind DS. Infarct Recurrence in Intracranial Atherosclerosis: Results from the MyRIAD Study. J Stroke Cerebrovasc Dis 2020; 30:105504. [PMID: 33276302 DOI: 10.1016/j.jstrokecerebrovasdis.2020.105504] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 10/05/2020] [Accepted: 11/21/2020] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Intracranial atherosclerotic disease (ICAD) is a common cause of ischemic stroke with a high risk of clinical stroke recurrence. Multiple mechanisms may underlie cerebral ischemia in this condition. The study's objective is to discern the mechanisms of recurrent ischemia in ICAD through imaging biomarkers of impaired antegrade flow, poor distal perfusion, abnormal vasoreactivity, and artery-to-artery embolism. METHODS This prospective multicenter observational study enrolled patients with recent (≤21 days) ischemic stroke or transient ischemic attack (TIA) caused by ICAD with 50-99% stenosis treated medically. We obtained baseline quantitative MRA (QMRA), perfusion MRI (PWI), transcranial Doppler vasoreactivity (VMR), and emboli detection studies (EDS). The primary outcome was ischemic stroke in the territory of the stenotic artery within 1 year of follow-up; secondary outcomes were TIA at 1 year and new infarcts in the territory on MRI at 6-8 weeks. RESULTS Amongst 102 of 105 participants with clinical follow-up (mean 253±131 days), the primary outcome occurred in 8.8% (12.7/100 patient-years), while 5.9% (8.5/100 patient-years) had a TIA. A new infarct in the territory of the symptomatic artery was noted in 24.7% at 6-8 weeks. A low flow state on QMRA was noted in 25.5%, poor distal perfusion on PWI in 43.5%, impaired vasoreactivity on VMR in 67.5%, and microemboli on EDS in 39.0%. No significant association was identified between these imaging biomarkers and primary or secondary outcomes. CONCLUSIONS Despite intensive medical management in ICAD, there is a high risk of clinical cerebrovascular events at 1 year and an even higher risk of new imaging-evident infarcts in the subacute period after index stroke. Hemodynamic and plaque instability biomarkers did not identify a higher risk group. Further work is needed to identify mechanisms of ischemic stroke and infarct recurrence and their consequence on long-term physical and cognitive outcomes. TRIAL REGISTRATION ClinicalTrials.gov: NCT02121028.
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Affiliation(s)
- Jose G Romano
- University of Miami, 1120 NW 14th Street, Suite 1357, Miami, FL 33136, USA.
| | | | | | - Edward Feldmann
- The University of Massachusetts Medical School-Baystate, Springfield, MA, USA.
| | - Rajbeer Sangha
- University of Alabama at Birmingham, Birmingham, AL, USA.
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Chang KH, Lee YH, Chen CY, Lin MF, Lin YC, Chen JH, Chan WP. Inter- and Intra-Rater Reliability of Individual Cerebral Blood Flow Measured by Quantitative Vessel-Flow Phase-Contrast MRI. J Clin Med 2020; 9:E3099. [PMID: 32992892 PMCID: PMC7601288 DOI: 10.3390/jcm9103099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/17/2020] [Accepted: 09/21/2020] [Indexed: 02/07/2023] Open
Abstract
Vessel flow quantification by two-dimensional (2D) phase-contrast magnetic resonance imaging (PC-MRI) using a three-dimensional (3D) magnetic resonance angiography (MRA) model to measure cerebral blood flow has unclear analytical reliability. The present study aimed to determine the inter- and intra-rater reliability of quantitative vessel-flow PC-MRI and potential factors influencing its consistency. We prospectively recruited 30 Asian participants (aged 20-90 years; 16 women; 22 healthy and 8 stroke patients) for performing 1.5-T MR equipped with a head coil. Each participant was first scanned for time-of-flight magnetic resonance angiography (TOF-MRA) images for localization of intracranial arteries. The 2D PC-MRI for each cerebral artery (total 13 arteries in fixed order) was performed twice by two well-trained operators in optimal position. Using the same 3D MRA as a map and facilitated with the non-invasive optimal vessel analysis (NOVA) system, each scan was taken on a plane perpendicular to the target artery. Two consecutive full 13-artery scans were performed at least 15 min apart after participants were removed from the scanner table and then repositioned. A total of four PC flow images obtained from each target artery were transmitted to a workstation facilitated with the NOVA system. Flow data were calculated semi-automatically by the NOVA system after a few simple steps. Two-way mixed-effect models and standard errors of measurements were used. In 13 cerebral arteries, repeatability, using the intra-rater estimate expressed as the average-measures intraclass correlation coefficient, ranged from 0.641 to 0.954, and reproducibility, using the inter-rater estimate, ranged from 0.672 to 0.977. Except in the middle cerebral artery and the distal segment of the anterior cerebral artery, repeatability and reproducibility were excellent (intraclass correlation coefficient exceeded 0.8). The use of quantitative vessel-flow PC-MRI is a precise means to measure blood flow in most target cerebral arteries. This was evidenced by inter-rater and intra-rater correlations that were good/excellent, indicating good reproducibility and repeatability.
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Affiliation(s)
- Kwang-Hwa Chang
- Department of Physical Medicine and Rehabilitation, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan;
- Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
- Graduate Institute of Injury Prevention and Control, College of Public Health, Taipei Medical University, Taipei 110, Taiwan
| | - Yuan-Hao Lee
- Department of Radiology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (Y.-H.L.); (M.-F.L.); (W.P.C.)
| | - Chia-Yuen Chen
- Department of Radiology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (Y.-H.L.); (M.-F.L.); (W.P.C.)
- Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
| | - Ming-Fang Lin
- Department of Radiology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (Y.-H.L.); (M.-F.L.); (W.P.C.)
- Department of Medical Imaging and Radiological Technology, Yuanpei University, Hsinchu 30015, Taiwan
| | - Ying Chin Lin
- Department of Family Medicine, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan;
- Department of Family Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
| | - Jyh-Horng Chen
- Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan;
- Neurobiology and Cognitive Science Center, National Taiwan University, Taipei 10051, Taiwan
| | - Wing P. Chan
- Department of Radiology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (Y.-H.L.); (M.-F.L.); (W.P.C.)
- Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
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Mechanisms of early Recurrence in Intracranial Atherosclerotic Disease (MyRIAD): Rationale and design. J Stroke Cerebrovasc Dis 2020; 29:105051. [PMID: 32912558 DOI: 10.1016/j.jstrokecerebrovasdis.2020.105051] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/08/2020] [Accepted: 06/09/2020] [Indexed: 11/20/2022] Open
Abstract
RATIONALE Intracranial atherosclerotic disease (ICAD) is the most common cause of ischemic stroke with the highest rate of recurrence, despite aggressive medical management. Diverse mechanisms may be responsible for ICAD-related cerebral ischemia, with potential therapeutic implications. Here we present the rationale, design and methods of the Mechanisms of Early Recurrence in Intracranial Atherosclerotic Disease (MyRIAD) study. The aim of MyRIAD is to determine the mechanisms of stroke in ICAD through physiologic imaging biomarkers that evaluate impaired antegrade flow, poor distal perfusion, abnormal vasoreactivity, artery to artery embolism, and their interaction. METHODS AND DESIGN This is a prospective observational study of patients with recently symptomatic (<21 days) ICAD with 50-99% stenosis treated medically and monitored for up to 1 year. An estimated 110 participants are recruited at 10 sites to identify the association between the presence of each mechanism of ischemia and recurrent stroke. The primary outcome is ischemic stroke in the territory of the symptomatic artery. Secondary outcomes include new cerebral infarction on MRI at 6-8 weeks and recurrent TIA in the territory of the symptomatic artery. DISCUSSION MyRIAD is positioned to define the role of specific mechanisms of recurrent ischemia in patients with symptomatic ICAD. This knowledge will allow the development and implementation of effective and specific treatments for this condition.
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Stapleton CJ, Chen YF, Shallwani H, Vakharia K, Turan TN, Woo HH, Derdeyn CP, Charbel FT, Siddiqui AH, Amin-Hanjani S. Submaximal Angioplasty for Symptomatic Intracranial Atherosclerotic Disease: A Meta-Analysis of Peri-Procedural and Long-Term Risk. Neurosurgery 2020; 86:755-762. [PMID: 31435656 PMCID: PMC7534488 DOI: 10.1093/neuros/nyz337] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 05/18/2019] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Symptomatic intracranial atherosclerotic disease (ICAD) is an important cause of stroke. Although the high periprocedural risk of intracranial stenting from recent randomized studies has dampened enthusiasm for such interventions, submaximal angioplasty without stenting may represent a safer endovascular treatment option. OBJECTIVE To examine the periprocedural and long-term risks associated with submaximal angioplasty for ICAD based on the available literature. METHODS All English language studies of intracranial angioplasty for ICAD were screened. Inclusion criteria were as follows: ≥ 5 patients, intervention with submaximal angioplasty alone, and identifiable periprocedural (30-d) outcomes. Analysis was co-nducted to identify the following: 1) periprocedural risk of any stroke (ischemic or hemorrh-agic) or death, and 2) stroke in the territory of the target vessel and fatal stroke beyond 30 d. Mixed effects logistic regression was used to summarize event rates. Funnel plot and rank correlation tests were employed to detect publication bias. The relative risk of periprocedural events from anterior vs posterior circulation disease intervention was also examined. RESULTS A total of 9 studies with 408 interventions in 395 patients met inclusion criteria. Six of these studies included 113 posterior circulation interventions. The estimated pooled rate for 30-d stroke or death following submaximal angioplasty was 4.9% (95% CI: 3.2%-7.5%), whereas the estimated pooled rate beyond 30 d was 3.7% (95% CI: 2.2%-6.0%). There was no statistical difference in estimated pooled rate for 30-d stroke or death between patients with anterior (4.8%, 95% CI: 2.8%-7.9%) vs posterior (5.3%, 95% CI: 2.4%-11.3%) circulation disease (P > .99). CONCLUSION Submaximal angioplasty represents a potentially promising intervention for symptomatic ICAD.
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Affiliation(s)
| | - Yi-Fan Chen
- Center for Clinical and Translational Science, University of Illinois at Chicago, Chicago, Illinois
| | - Hussain Shallwani
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York
- Department of Neurosurgery, Gates Vascular Institute, Kaleida Health, Buffalo, New York
| | - Kunal Vakharia
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York
- Department of Neurosurgery, Gates Vascular Institute, Kaleida Health, Buffalo, New York
| | - Tanya N Turan
- Department of Neurology, Medical University of South Carolina, Charleston, South Carolina
| | - Henry H Woo
- Department of Neurosurgery, North Shore University Hospital, Northwell Health, Manhasset, New York
| | - Colin P Derdeyn
- Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City, Iowa
| | - Fady T Charbel
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois
| | - Adnan H Siddiqui
- Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York
- Department of Neurosurgery, Gates Vascular Institute, Kaleida Health, Buffalo, New York
- Canon Stroke and Vascular Research Center, University at Buffalo, Buffalo, New York
- Department of Radiology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York
| | - Sepideh Amin-Hanjani
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois
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Helthuis JH, van Doormaal TP, Amin-Hanjani S, Du X, Charbel FT, Hillen B, van der Zwan A. A patient-specific cerebral blood flow model. J Biomech 2020; 98:109445. [DOI: 10.1016/j.jbiomech.2019.109445] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 10/19/2019] [Accepted: 10/21/2019] [Indexed: 01/01/2023]
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Holmgren M, Wåhlin A, Dunås T, Malm J, Eklund A. Assessment of Cerebral Blood Flow Pulsatility and Cerebral Arterial Compliance With 4D Flow MRI. J Magn Reson Imaging 2019; 51:1516-1525. [PMID: 31713964 PMCID: PMC7216927 DOI: 10.1002/jmri.26978] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 10/08/2019] [Accepted: 10/08/2019] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Four-dimensional flow magnetic resonance imaging (4D flow MRI) enables efficient investigation of cerebral blood flow pulsatility in the cerebral arteries. This is important for exploring hemodynamic mechanisms behind vascular diseases associated with arterial pulsations. PURPOSE To investigate the feasibility of pulsatility assessments with 4D flow MRI, its agreement with reference two-dimensional phase-contrast MRI (2D PC-MRI) measurements, and to demonstrate how 4D flow MRI can be used to assess cerebral arterial compliance and cerebrovascular resistance in major cerebral arteries. STUDY TYPE Prospective. SUBJECTS Thirty-five subjects (20 women, 79 ± 5 years, range 70-91 years). FIELD STRENGTH/SEQUENCE 4D flow MRI (PC-VIPR) and 2D PC-MRI acquired with a 3T scanner. ASSESSMENT Time-resolved flow was assessed in nine cerebral arteries. From the pulsatile flow waveform in each artery, amplitude (ΔQ), volume load (ΔV), and pulsatility index (PI) were calculated. To reduce high-frequency noise in the 4D flow MRI data, the flow waveforms were low-pass filtered. From the total cerebral blood flow, total PI (PItot ), total volume load (ΔVtot ), cerebral arterial compliance (C), and cerebrovascular resistance (R) were calculated. STATISTICAL TESTS Two-tailed paired t-test, intraclass correlation (ICC). RESULTS There was no difference in ΔQ between 4D flow MRI and the reference (0.00 ± 0.022 ml/s, mean ± SEM, P = 0.97, ICC = 0.95, n = 310) with a cutoff frequency of 1.9 Hz and 15 cut plane long arterial segments. For ΔV, the difference was -0.006 ± 0.003 ml (mean ± SEM, P = 0.07, ICC = 0.93, n = 310) without filtering. Total R was 11.4 ± 2.41 mmHg/(ml/s) (mean ± SD) and C was 0.021 ± 0.009 ml/mmHg (mean ± SD). ΔVtot was 1.21 ± 0.29 ml (mean ± SD) with an ICC of 0.82 compared with the reference. PItot was 1.08 ± 0.21 (mean ± SD). DATA CONCLUSION We successfully assessed 4D flow MRI cerebral arterial pulsatility, cerebral arterial compliance, and cerebrovascular resistance. Averaging of multiple cut planes and low-pass filtering was necessary to assess accurate peak-to-peak features in the flow rate waveforms. LEVEL OF EVIDENCE 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:1516-1525.
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Affiliation(s)
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Tora Dunås
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden.,Center for Demographic and Aging Research, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
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Amin-Hanjani S, Stapleton CJ, Du X, Rose-Finnell L, Pandey DK, Elkind MSV, Zipfel GJ, Liebeskind DS, Silver FL, Kasner SE, Caplan LR, Derdeyn CP, Gorelick PB, Charbel FT. Hypoperfusion Symptoms Poorly Predict Hemodynamic Compromise and Stroke Risk in Vertebrobasilar Disease. Stroke 2019; 50:495-497. [PMID: 30580717 DOI: 10.1161/strokeaha.118.023101] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose- Cerebral hypoperfusion symptoms (defined as symptoms related to change in position, effort or exertion, or recent change in antihypertensive medication) have been used in stroke studies as a surrogate for detecting hemodynamic compromise. However, the validity of these symptoms in identifying flow compromise in patients has not been well established. We examined whether hypoperfusion symptoms correlated with quantitative measurements of flow compromise in the prospective, observational VERiTAS study (Vertebrobasilar Flow Evaluation and Risk of Transient Ischemic Attack and Stroke). Methods- VERiTAS enrolled patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral or basilar arteries. Hemodynamic status using vertebrobasilar large vessel flow was measured using quantitative magnetic resonance angiography, and patients were designated as low, borderline, or normal flow based on distal territory regional flow, incorporating collateral capacity. The presence of qualifying event hypoperfusion symptoms was assessed relative to the quantitatively determined flow status (normal versus borderline/low) and also examined as a predictor of subsequent stroke risk. Results- Of the 72 enrolled subjects, 66 had data on hypoperfusion symptoms available. On initial quantitative magnetic resonance angiography designation, 43 subjects were designated as normal flow versus 23 subjects designated as low flow (n=16) or borderline flow (n=7). Of these, 5 (11.6%) normal flow and 3 (13.0%) low/borderline flow subjects reported at least one qualifying event hypoperfusion symptom ( P=0.99, Fisher exact test). Hypoperfusion symptoms had a positive predictive value of 37.5% and negative predictive value of 65.5% for low/borderline flow status. Compared with flow status, which strongly predicted subsequent stroke risk, hypoperfusion symptoms were not associated with stroke outcome ( P=0.87, log-rank test). Conclusions- These results suggest that hypoperfusion symptoms alone correlate poorly with actual hemodynamic compromise as assessed by quantitative magnetic resonance angiography and subsequent stroke risk in vertebrobasilar disease, and are not a reliable surrogate for flow measurement. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT00590980.
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Affiliation(s)
- Sepideh Amin-Hanjani
- From the Department of Neurosurgery (S.A.-H., C.J.S., X.D., L.R.-F., F.T.C.), University of Illinois at Chicago
| | - Christopher J Stapleton
- From the Department of Neurosurgery (S.A.-H., C.J.S., X.D., L.R.-F., F.T.C.), University of Illinois at Chicago
| | - Xinjian Du
- From the Department of Neurosurgery (S.A.-H., C.J.S., X.D., L.R.-F., F.T.C.), University of Illinois at Chicago
| | - Linda Rose-Finnell
- From the Department of Neurosurgery (S.A.-H., C.J.S., X.D., L.R.-F., F.T.C.), University of Illinois at Chicago
| | - Dilip K Pandey
- Department of Neurology and Rehabilitation (D.K.P.), University of Illinois at Chicago
| | - Mitchell S V Elkind
- Departments of Neurology and Epidemiology, Columbia University, New York, NY (M.S.V.E.)
| | - Gregory J Zipfel
- Departments of Neurosurgery and Neurology, Washington University in St Louis, MO (G.J.Z.)
| | - David S Liebeskind
- Neurovascular Imaging and Research Core and Department of Neurology, University of California at Los Angeles (D.S.L.)
| | - Frank L Silver
- Division of Neurology, Department of Medicine, University of Toronto, Canada (F.L.S.)
| | - Scott E Kasner
- Department of Neurology, University of Pennsylvania, Philadelphia (S.E.K.)
| | - Louis R Caplan
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA (L.R.C.)
| | - Colin P Derdeyn
- Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City (C.P.D.)
| | - Philip B Gorelick
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL (P.B.G.).,Population Health Research Institute affiliated with McMaster University Faculty of Health Sciences and Hamilton University Health Sciences, Ontario, Canada (P.B.G.).,Departments of Translational Science and Molecular Medicine, Michigan State University College of Human Medicine and Mercy Health Hauenstein Neurosciences, Grand Rapids, MI (P.B.G.)
| | - Fady T Charbel
- From the Department of Neurosurgery (S.A.-H., C.J.S., X.D., L.R.-F., F.T.C.), University of Illinois at Chicago
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Cattaneo G, Bräuner C, Siekmeyer G, Ding A, Bauer S, Wohlschlögel M, Lang L, Hierlemann T, Akimov M, Schlensak C, Schüßler A, Wendel HP, Krajewski S. In vitro investigation of chemical properties and biocompatibility of neurovascular braided implants. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2019; 30:67. [PMID: 31165278 PMCID: PMC7695648 DOI: 10.1007/s10856-019-6270-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 05/06/2019] [Accepted: 05/18/2019] [Indexed: 06/02/2023]
Abstract
Braiding of Nitinol micro wires is an established technology for the manufacturing of fine-meshed neurovascular implants for tortuous vessel geometries. Electropolishing of wires before the braiding process has the potential to improve the in vitro behaviour in terms of thrombogenicity and endothelial cell proliferation. In this study, we present the first in vitro investigation of braided electropolished/blue oxide Nitinol samples in a blood flow loop, showing a significantly lower activation of the coagulation pathway (represented by the TAT III marker) and a tendency towards reduced platelet adhesion. Furthermore, we applied the same surface treatment on flat disks and measured protein adhesion as well as endothelial cell proliferation. We compared our results to non-electropolished samples with a native oxide surface. While platelet deposition was reduced on electropolished/blue oxide surface, a significant increase of endothelial cell seeding was observed. Investigation of inflammatory marker expression in endothelial cells provided divergent results depending on the marker tested, demanding closer investigation. Surface analysis using Auger electron spectroscopy revealed a thin layer mainly consisting of titanium oxynitride or titanium oxide + titanium nitride as a potential cause of the improved biological performance. Translated to the clinical field of intracranial aneurysm treatment, the improved biocompatibility has the potential to increase both safety (low thrombogenicity) and effectiveness (aneurysm neck reconstruction).
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Affiliation(s)
| | | | | | | | | | | | - Lisa Lang
- Department of Thoracic and Cardiovascular Surgery, Clinical Research Laboratory, University Medical Center, Tuebingen, Germany
| | - Teresa Hierlemann
- Department of Thoracic and Cardiovascular Surgery, Clinical Research Laboratory, University Medical Center, Tuebingen, Germany
| | - Maria Akimov
- Department of Thoracic and Cardiovascular Surgery, Clinical Research Laboratory, University Medical Center, Tuebingen, Germany
| | - Christian Schlensak
- Department of Thoracic and Cardiovascular Surgery, Clinical Research Laboratory, University Medical Center, Tuebingen, Germany
| | | | - Hans-Peter Wendel
- Department of Thoracic and Cardiovascular Surgery, Clinical Research Laboratory, University Medical Center, Tuebingen, Germany
| | - Stefanie Krajewski
- Department of Thoracic and Cardiovascular Surgery, Clinical Research Laboratory, University Medical Center, Tuebingen, Germany
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Vali A, Aristova M, Vakil P, Abdalla R, Prabhakaran S, Markl M, Ansari SA, Schnell S. Semi-automated analysis of 4D flow MRI to assess the hemodynamic impact of intracranial atherosclerotic disease. Magn Reson Med 2019; 82:749-762. [PMID: 30924197 DOI: 10.1002/mrm.27747] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/03/2019] [Accepted: 03/02/2019] [Indexed: 01/02/2023]
Abstract
PURPOSE This study evaluated the feasibility of using 4D flow MRI and a semi-automated analysis tool to assess the hemodynamic impact of intracranial atherosclerotic disease (ICAD). The ICAD impact was investigated by evaluating pressure drop (PD) at the atherosclerotic stenosis and changes in cerebral blood flow distribution in patients compared to healthy controls. METHODS Dual-venc 4D flow MRI was acquired in 25 healthy volunteers and 16 ICAD patients (ICA, N = 3; MCA, N = 13) with mild (<50%), moderate (50-69%), or severe (>70%) intracranial stenosis. A semi-automated analysis tool was developed to quantify velocity and flow from 4D flow MRI and to evaluate cerebral blood flow redistribution. PD at stenosis was estimated using the Bernoulli equation. The PD calculation was examined by an in vitro phantom study against flow simulations. RESULTS Flow analysis in controls indicated symmetry in blood flow rate (FR) and peak velocity (PV) between the brain hemispheres. For patients, PV in the affected hemisphere was significantly (65%) higher than the normal side (P = 0.002). However, FR to both hemispheres of the brain was the same. The PD depicted significant correlation with PV asymmetry in patients (ρ = 0.67 and P = 0.02), and it was significantly higher for severe compared to moderate stenosis (3.73 vs. 2.30 mm Hg, P = 0.02). CONCLUSION 4D flow MRI quantification enables assessment of the hemodynamic impact of ICAD. The significant difference of the PD between patients with severe and moderate stenosis and its correlation with PV asymmetry suggest that PD may be a pertinent hemodynamic biomarker to evaluate ICAD.
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Affiliation(s)
- Alireza Vali
- Department of Radiology, Northwestern University, Chicago, Illinois
| | - Maria Aristova
- Department of Radiology, Northwestern University, Chicago, Illinois.,Department of Biomedical Engineering, Northwestern University, Evanston, Illinois
| | - Parmede Vakil
- Department of Radiology, Northwestern University, Chicago, Illinois.,Department of Neurological Surgery, Northwestern University, Chicago, Illinois
| | - Ramez Abdalla
- Department of Radiology, Northwestern University, Chicago, Illinois.,Department of Neurological Surgery, Northwestern University, Chicago, Illinois
| | | | - Michael Markl
- Department of Radiology, Northwestern University, Chicago, Illinois.,Department of Biomedical Engineering, Northwestern University, Evanston, Illinois
| | - Sameer A Ansari
- Department of Radiology, Northwestern University, Chicago, Illinois.,Department of Neurology, Northwestern University, Chicago, Illinois.,Department of Neurological Surgery, Northwestern University, Chicago, Illinois
| | - Susanne Schnell
- Department of Radiology, Northwestern University, Chicago, Illinois
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40
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Chen CY, Li CW, Mak HKF, Lin MF, Chan WP. Combined native magnetic resonance angiography, flow-quantifying, and perfusion-imaging for impending second-stroke assessment. Quant Imaging Med Surg 2019; 9:521-529. [PMID: 31032198 DOI: 10.21037/qims.2019.03.10] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This special report introduces native flow quantitative imaging for evaluating stroke risk. Moreover, the advantage of combining three imaging techniques [magnetic resonance angiography (MRA), phase-contrast (PC) flow imaging, and arterial spin-labeling imaging] is shown to be beneficial for responding to ischemia and preserving viable neurons. These quantitative imaging techniques provide authoritative information for diagnosing impending stroke and selecting appropriate treatment.
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Affiliation(s)
- Chia-Yuen Chen
- Department of Radiology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chia-Wei Li
- Department of Radiology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Henry Ka Fung Mak
- Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong SAR, China
| | - Ming-Fang Lin
- Department of Radiology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Medical Imaging and Radiological Technology, Yuanpei University, Hsinchu, Taiwan
| | - Wing P Chan
- Department of Radiology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
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Ausman JI, Liebeskind DS, Gonzalez N, Saver J, Martin N, Villablanca JP, Vespa P, Duckwiler G, Jahan R, Niu T, Salamon N, Yoo B, Tateshima S, Buitrago Blanco MM, Starkman S. A review of the diagnosis and management of vertebral basilar (posterior) circulation disease. Surg Neurol Int 2018; 9:106. [PMID: 29930872 PMCID: PMC5991286 DOI: 10.4103/sni.sni_373_17] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 12/26/2017] [Indexed: 12/28/2022] Open
Abstract
We have reviewed the English literature published in the last 70 years on Diseases of the Vertebral Basilar Circulation, or Posterior Circulation Disease (PCD). We have found that errors have been made in the conduct and interpretation of these studies that have led to incorrect approaches to the management of PCD. Because of the difficulty in evaluating the PC, the management of PCD has been incorrectly applied from anterior circulation disease (ACD) experience to PCD. PCD is a common form of stroke affecting 20-40% patients with stroke. Yet, the evidence is strong that the Anterior Circulation (AC) and Posterior Circulations (PC) differ in their pathology, in their clinical presentations, in the rapidity of development of symptoms, in optimal imaging methods, and in available treatments. There appears to be two categories of patients who present with PCD. The first, acute basilar artery occlusion has a more rapid onset. The diagnosis must be made quickly and if imaging proves a diagnosis of Basilar Artery Occlusion (BAO), the treatment of choice is Interventional removal of the basilar artery thrombosis or embolus. The second category of PCD and the most commonly seen PCD disease process presents with non-specific symptoms and early warnings of PCD that now can be related to ischemic events in the entire PC vessels. These warning symptoms and signs occur much earlier than those in the AC. IA angiography is still the gold standard of diagnosis and is superior in definition to MR and CT angiography which are commonly used as a convenient screening imaging tool to evaluate PCD but are both inferior to IA angiography in definition for lesions below 3-4 mm. In at least two reported studies 7T MR angiography appears superior to other imaging modalities and will become the gold standard of imaging of PCD in the future. Medical treatments applied to the ACD have not been proven of value in specific forms of PCD. Interventional therapy was promising but of unproven value in Randomized Controlled Trials (RCT) except for the treatment of Basilar Artery Occlusion (BAO). Surgical revascularization has been proved to be highly successful in patients, who are refractory to medical therapy. These studies have been ignored by the scientific community basically because of an incorrect interpretation of the flawed EC-IC Bypass Trial in 1985 as applying to all stroke patients. Moreover, the EC-IC Bypass Study did not include PCD patients in their study population, but the study results were extrapolated to patients with PCD without any scientific basis. This experience led clinicians to an incorrect bias that surgical treatments are of no value in PCD. Thus, incorrectly, surgical treatments of PCD have not been considered among the therapeutic possibilities for PCD. QMRA is a new quantitative MR technique that measures specific blood flow in extra and intracranial vessels. QMRA has been used to select those patients who may benefit from medical, or interventional, or surgical treatment for PCD based on flow determinations with a high success rate. QMRA accurately predicts the flows in many large and small vessels in the PC and AC and clearly indicates that both circulations are intimately related. From medical and surgical studies, the longer one waits for surgical treatment the higher the risk of a poor outcome results. This observation becomes obvious when the rapidity of development of PCD is compared with ACD. Recent advances in endovascular therapy in the treatment of acute basilar thrombosis is a clear sign that early diagnosis and treatment of PCD will reduce the morbidity and mortality of these diseases. In this review it is evident that there are multiple medical and surgical treatments for PCD depending upon the location of the lesion(s) and the collateral circulation demonstrated. It is clear that the AC and PC have significant differences. With the exception of the large population studies from Oxford England, the reported studies on the management of PCD in the literature represent small selected subsets of the universe of PC diseases, the information from which is not generalizable to the universe of PCD patients. At this point in the history of PCD, there are not large enough databases of similar patients to provide a basis for valid randomized studies, with the exception of the surgical studies. Thus, a high index of suspicion of the early warning symptoms of PCD should lead to a rapid individual clinical assessment of patients selecting those with PCD. Medical, interventional, and/or surgical treatments should be chosen based on knowledge presented in this review. Recording the results in a national Registry on a continuing basis will provide the data that may help advance the management of PCD based on larger data bases of well documented patient information to guide the selection of future therapies for PCD treatments. It is also clear that the management of patients within the complex of diseases that comprise PCD should be performed in centers with expertise in the imaging, medical, interventional and surgical approaches to diseases of the PCD.
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Affiliation(s)
- James I. Ausman
- Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - David S. Liebeskind
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
- Neurovascular Imaging Research Core, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Nestor Gonzalez
- Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Jeffrey Saver
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Neil Martin
- Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - J. Pablo Villablanca
- Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Paul Vespa
- Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, California, USA
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Gary Duckwiler
- Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Reza Jahan
- Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Tianyi Niu
- Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Noriko Salamon
- Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Bryan Yoo
- Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Satoshi Tateshima
- Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Manuel M. Buitrago Blanco
- Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, California, USA
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Sidney Starkman
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
- Department of Emergency Medicine, David Geffen School of Medicine, University of California, Los Angeles, California, USA
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Paliwal N, Damiano RJ, Varble NA, Tutino VM, Dou Z, Siddiqui AH, Meng H. Methodology for Computational Fluid Dynamic Validation for Medical Use: Application to Intracranial Aneurysm. J Biomech Eng 2017; 139:2653365. [PMID: 28857116 PMCID: PMC5686786 DOI: 10.1115/1.4037792] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 08/28/2017] [Indexed: 11/08/2022]
Abstract
Computational fluid dynamics (CFD) is a promising tool to aid in clinical diagnoses of cardiovascular diseases. However, it uses assumptions that simplify the complexities of the real cardiovascular flow. Due to high-stakes in the clinical setting, it is critical to calculate the effect of these assumptions in the CFD simulation results. However, existing CFD validation approaches do not quantify error in the simulation results due to the CFD solver's modeling assumptions. Instead, they directly compare CFD simulation results against validation data. Thus, to quantify the accuracy of a CFD solver, we developed a validation methodology that calculates the CFD model error (arising from modeling assumptions). Our methodology identifies independent error sources in CFD and validation experiments, and calculates the model error by parsing out other sources of error inherent in simulation and experiments. To demonstrate the method, we simulated the flow field of a patient-specific intracranial aneurysm (IA) in the commercial CFD software star-ccm+. Particle image velocimetry (PIV) provided validation datasets for the flow field on two orthogonal planes. The average model error in the star-ccm+ solver was 5.63 ± 5.49% along the intersecting validation line of the orthogonal planes. Furthermore, we demonstrated that our validation method is superior to existing validation approaches by applying three representative existing validation techniques to our CFD and experimental dataset, and comparing the validation results. Our validation methodology offers a streamlined workflow to extract the "true" accuracy of a CFD solver.
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Affiliation(s)
- Nikhil Paliwal
- Department of Mechanical and Aerospace Engineering,
University at Buffalo,
Buffalo, NY 14260
- Toshiba Stroke and Vascular Research Center,
University at Buffalo,
Buffalo, NY 14203
| | - Robert J. Damiano
- Department of Mechanical and Aerospace Engineering,
University at Buffalo,
Buffalo, NY 14260
- Toshiba Stroke and Vascular Research Center,
University at Buffalo,
Buffalo, NY 14203
| | - Nicole A. Varble
- Department of Mechanical and Aerospace Engineering,
University at Buffalo,
Buffalo, NY 14260
- Toshiba Stroke and Vascular Research Center,
University at Buffalo,
Buffalo, NY 14203
| | - Vincent M. Tutino
- Toshiba Stroke and Vascular Research Center,
University at Buffalo,
Buffalo, NY 14203
- Department of Biomedical Engineering,
University at Buffalo,
Buffalo, NY 14260
| | - Zhongwang Dou
- Department of Mechanical and Aerospace Engineering,
University at Buffalo,
Buffalo, NY 14260
| | - Adnan H. Siddiqui
- Toshiba Stroke and Vascular Research Center,
University at Buffalo,
Buffalo, NY 14260
- Department of Neurosurgery,
University at Buffalo,
Buffalo, NY 14226
| | - Hui Meng
- Department of Mechanical and Aerospace Engineering,
University at Buffalo,
324 Jarvis Hall,
Buffalo, NY 14260
- Toshiba Stroke and Vascular Research Center,
University at Buffalo,
Buffalo, NY 14203
- Department of Biomedical Engineering,
University at Buffalo,
Buffalo, NY 14260
- Department of Neurosurgery,
University at Buffalo,
Buffalo, NY 14226
e-mail:
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43
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Brunozzi D, Shakur SF, Ismail R, Linninger A, Hsu CY, Charbel FT, Alaraj A. Correlation Between Contrast Time-Density Time on Digital Subtraction Angiography and Flow: An in Vitro Study. World Neurosurg 2017; 110:e315-e320. [PMID: 29133005 DOI: 10.1016/j.wneu.2017.10.178] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 10/30/2017] [Indexed: 11/20/2022]
Abstract
BACKGROUND AND PURPOSE Digital subtraction angiography (DSA) provides an excellent anatomic characterization of cerebral vasculature, but hemodynamic assessment is often qualitative and subjective. Various clinical algorithms have been produced to semiquantify flow from the data obtained from DSA, but few have tested them against reliable flow values. METHODS An arched flow model was created and injected with contrast material. Seventeen injections were acquired in anterior-posterior and lateral DSA projections, and 4 injections were acquired in oblique projection. Image intensity change over the angiogram cycle of each DSA run was analyzed through a custom MATLAB code. Time-density plots obtained were divided into 3 components (time-density times, TDTs): TDT10%-100% (time needed for contrast material to change image intensity from 10% to 100%), TDT100%-10% (time needed for contrast material to change image intensity from 100% to 10%), and TDT25%-25% (time needed for contrast material to change from 25% image intensity to 25%). Time-density index (TDI) was defined as model cross-sectional area to TDT ratio, and it was measured against different flow rates. RESULTS TDI10%-100%, TDI100%-10%, and TDI25%-25% all correlated significantly with flow (P < 0.001). TDI10%-100%, TDI100%-10%, and TDI25%-25% showed, respectively, a correlation coefficient of 0.91, 0.91, and 0.97 in the anterior-posterior DSA projections (P < 0.001). In the lateral DSA projection, TDI100%-10% showed a weaker correlation (r = 0.57; P = 0.03). Also in the oblique DSA projection, TDIs correlated significantly with flow. CONCLUSIONS TDI on DSA correlates significantly with flow. Although in vitro studies might overlook conditions that occur in patients, this method appears to correlate with the flow and could offer a semiquantitative method to evaluate the cerebral blood flow.
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Affiliation(s)
- Denise Brunozzi
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Sophia F Shakur
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Rahim Ismail
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Andreas Linninger
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Chih-Yang Hsu
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Fady T Charbel
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Ali Alaraj
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA.
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Chnafa C, Bouillot P, Brina O, Delattre BMA, Vargas MI, Lovblad KO, Pereira VM, Steinman DA. Vessel calibre and flow splitting relationships at the internal carotid artery terminal bifurcation. Physiol Meas 2017; 38:2044-2057. [DOI: 10.1088/1361-6579/aa92bf] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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45
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Bouillot P, Delattre BMA, Brina O, Ouared R, Farhat M, Chnafa C, Steinman DA, Lovblad KO, Pereira VM, Vargas MI. 3D phase contrast MRI: Partial volume correction for robust blood flow quantification in small intracranial vessels. Magn Reson Med 2017; 79:129-140. [PMID: 28244132 DOI: 10.1002/mrm.26637] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 01/19/2017] [Accepted: 01/19/2017] [Indexed: 11/11/2022]
Abstract
PURPOSE Recent advances in 3D-PCMRI (phase contrast MRI) sequences allow for measuring the complex hemodynamics in cerebral arteries. However, the small size of these vessels vs spatial resolution can lead to non-negligible partial volume artifacts, which must be taken into account when computing blood flow rates. For this purpose, we combined the velocity information provided by 3D-PCMRI with vessel geometry measured with 3DTOF (time of flight MRI) or 3DRA (3D rotational angiography) to correct the partial volume effects in flow rate assessments. METHODS The proposed methodology was first tested in vitro on cylindrical and patient specific vessels subject to fully controlled pulsatile flows. Both 2D- and 3D-PCMRI measurements using various spatial resolutions ranging from 20 to 1.3 voxels per vessel diameter were analyzed and compared with flowmeter baseline. Second, 3DTOF, 2D- and 3D-PCMRI measurements were performed in vivo on 35 patients harboring internal carotid artery (ICA) aneurysms indicated for endovascular treatments requiring 3DRA imaging. RESULTS The in vitro 2D- and 3D-PCMRI mean flow rates assessed with partial volume correction showed very low sensitivity to the acquisition resolution above ≈2 voxels per vessel diameter while uncorrected flow rates deviated critically when decreasing the spatial resolution. 3D-PCMRI flow rates measured in vivo in ICA agreed very well with 2D-PCMRI data and a good flow conservation was observed at the C7 bifurcation. Globally, partial volume correction led to 10-15% lower flow rates than uncorrected values as those reported in most of the published studies on intracranial flows. CONCLUSION Partial volume correction may improve the accuracy of PCMRI flow rate measurements especially in small vessels such as intracranial arteries. Magn Reson Med 79:129-140, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Pierre Bouillot
- Division of Neuroradiology, Geneva University Hospitals & Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Laboratory for Hydraulic Machines (LMH), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Bénédicte M A Delattre
- Division of Radiology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland
| | - Olivier Brina
- Division of Neuroradiology, Geneva University Hospitals & Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, University Health Network, Toronto, Canada
| | - Rafik Ouared
- Division of Neuroradiology, Geneva University Hospitals & Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Mohamed Farhat
- Laboratory for Hydraulic Machines (LMH), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Christophe Chnafa
- Biomedical Simulation Laboratory, Department of Mechanical & Industrial Engineering, University of Toronto, Toronto, Canada
| | - David A Steinman
- Biomedical Simulation Laboratory, Department of Mechanical & Industrial Engineering, University of Toronto, Toronto, Canada
| | - Karl-Olof Lovblad
- Division of Neuroradiology, Geneva University Hospitals & Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Vitor M Pereira
- Division of Neuroradiology, Geneva University Hospitals & Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, University Health Network, Toronto, Canada.,Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University Health Network, Toronto, Canada
| | - Maria I Vargas
- Division of Neuroradiology, Geneva University Hospitals & Faculty of Medicine, University of Geneva, Geneva, Switzerland
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Measuring Cerebral Blood Flow in Moyamoya Angiopathy by Quantitative Magnetic Resonance Angiography Noninvasive Optimal Vessel Analysis. Neurosurgery 2017; 81:921-927. [DOI: 10.1093/neuros/nyw122] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 12/08/2016] [Indexed: 11/14/2022] Open
Abstract
Abstract
BACKGROUND
Moyamoya disease causes progressive occlusion of the supraclinoidal internal carotid artery, and middle, anterior, and less frequently the posterior cerebral arteries, carrying the risk of stroke. Blood flow is often partially reconstituted by compensatory moyamoya collaterals and sometimes the posterior circulation. Cerebral revascularization can further augment blood flow. These changes to blood flow within the cerebral vessels, however, are not well characterized.
OBJECTIVE
To evaluate blood flow changes resulting from the disease process and revascularization surgery using quantitative magnetic resonance angiography with noninvasive optimal vessel analysis (NOVA).
METHODS
We retrospectively analyzed 190 preoperative and postoperative imaging scans in 66 moyamoya patients after revascularization surgery. Images were analyzed for blood flow using NOVA and compared with preoperative angiographic staging and postoperative blood flow. Blood flow rates within superficial temporal artery grafts were compared based on angiographic evidence of patency.
RESULTS
Diseased vessels had lower blood flow, correlating with angiographic staging. Flow in posterior cererbal and basilar arteries increased with disease severity, particularly when both the anterior and middle cerebral arteries were occluded. Basilar artery flow and ipsilateral internal carotid artery flow decreased after surgery. Flow rates were different between angiographically robust and poor direct bypass grafts, as well as between robust and patent grafts.
CONCLUSION
Preoperative changes in cerebral vessel flow as measured by NOVA correlated with angiographic disease progression. NOVA demonstrated that preoperative augmentation of the posterior circulation decreased after surgery. This report is the first to quantify the shift in collateral supply from the posterior circulation to the bypass graft.
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Raz N, Daugherty AM, Sethi SK, Arshad M, Haacke EM. Age differences in arterial and venous extra-cerebral blood flow in healthy adults: contributions of vascular risk factors and genetic variants. Brain Struct Funct 2017; 222:2641-2653. [PMID: 28120105 DOI: 10.1007/s00429-016-1362-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 12/24/2016] [Indexed: 01/01/2023]
Abstract
Sufficient cerebral blood flow (CBF) and venous drainage are critical for normal brain function, and their alterations can affect brain aging. However, to date, most studies focused on arterial CBF (inflow) with little attention paid to the age differences in venous outflow. We measured extra-cerebral arterial and venous blood flow rates with phase-contrast MRI and assessed the influence of vascular risk factors and genetic polymorphisms (ACE insertion/deletion, COMT val158met, and APOEε4) in 73 adults (age 18-74 years). Advanced age, elevated vascular risk, ACE Deletion, and COMT met alleles were linked to lower in- and outflow, with no effects of APOE ε4 noted. Lower age-related CBF rate was unrelated to brain volume and was observed only in val homozygotes of COMTval158met. Thus, in a disease-free population, age differences in CBF may be notable only in persons with high vascular risk and carriers of genetic variants associated with vasoconstriction and lower dopamine availability. It remains to be established if treatments targeting alleviation of the mutable factors can improve the course of cerebrovascular aging in spite of the immutable genetic influence.
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Affiliation(s)
- Naftali Raz
- Institute of Gerontology, Wayne State University, 87 E Ferry St. 226 Knapp Bldg., Detroit, MI, 48202, USA. .,Department of Psychology, Wayne State University, 5057 Woodward Ave., Detroit, MI, 48202, USA.
| | - Ana M Daugherty
- Institute of Gerontology, Wayne State University, 87 E Ferry St. 226 Knapp Bldg., Detroit, MI, 48202, USA.,Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, 405 N Matthews Ave., Urbana, IL, 61801, USA
| | - Sean K Sethi
- The MRI Institute of Biomedical Research, 440 E Ferry St., Detroit, MI, 48202, USA
| | - Muzamil Arshad
- Institute of Gerontology, Wayne State University, 87 E Ferry St. 226 Knapp Bldg., Detroit, MI, 48202, USA.,Department of Psychiatry and Behavioral Sciences, Wayne State University, 3990 John R, Detroit, MI, 48201, USA
| | - E Mark Haacke
- The MRI Institute of Biomedical Research, 440 E Ferry St., Detroit, MI, 48202, USA.,Department of Radiology, Wayne State University, 3990 John R, Detroit, MI, 48201, USA
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Pu Y, Lan L, Leng X, Wong LKS, Liu L. Intracranial atherosclerosis: From anatomy to pathophysiology. Int J Stroke 2017; 12:236-245. [PMID: 28067615 DOI: 10.1177/1747493016685716] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Intracranial atherosclerotic stenosis is an important etiology subtype of ischemic stroke. Stenosis severity was thought to be the main reference index for clinical treatment and research. However, stenosis could not reflect the ischemia risk completely, instead the hemodynamic state across the lesion, the extent of collateral circulation, and perfusion impairment downstream the stenosis are more important. Aims We write this review aimed to summarize novel angiographic methods applied in the evaluation of functional severity of ICAS, and commented on their limitations and prospects in future research. Summary of review The main methods to estimate cerebral blood flow including fractional flow assessed by signal intensity ratio, computational fluid dynamics analysis or pressure wire, quantitative magnetic resonance angiography. Fractional flow as a series cerebral hemodynamic parameters may reflect the status of collateral circulation and cerebral blood flow. But the accuracy of the methods was not validated. The method to calculate fractional flow reserve in cardiovascular disease cannot duplicate in cerebrovascular disease. Fractional flow measurement by floating a pressure guidewire across the intracranial stenosis was technically feasible and safe. In the future researches, a non-invasive method should be established to identify high-risk intracranial lesions and may help in decision-making. Conclusions The relationship between stenosis and cerebral blood flow was individualized. Cerebral hemodynamic criteria should be used to screen patients to endovascular treatment, which will optimize the diagnosis and treatment strategies for patients with symptomatic intracranial artery stenosis.
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Affiliation(s)
- Yuehua Pu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Linfang Lan
- Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Hong Kong SAR, China
| | - Xinyi Leng
- Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Hong Kong SAR, China
| | - Lawrence KS Wong
- Department of Medicine and Therapeutics, the Chinese University of Hong Kong, Hong Kong SAR, China
| | - Liping Liu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
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Vortex Analysis of Intra-Aneurismal Flow in Cerebral Aneurysms. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2016; 2016:7406215. [PMID: 27891172 PMCID: PMC5116551 DOI: 10.1155/2016/7406215] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 08/27/2016] [Accepted: 09/15/2016] [Indexed: 11/18/2022]
Abstract
This study aims to develop an alternative vortex analysis method by measuring structure ofIntracranial aneurysm (IA) flow vortexes across the cardiac cycle, to quantify temporal stability of aneurismal flow. Hemodynamics were modeled in “patient-specific” geometries, using computational fluid dynamics (CFD) simulations. Modified versions of known λ2 and Q-criterion methods identified vortex regions; then regions were segmented out using the classical marching cube algorithm. Temporal stability was measured by the degree of vortex overlap (DVO) at each step of a cardiac cycle against a cycle-averaged vortex and by the change in number of cores over the cycle. No statistical differences exist in DVO or number of vortex cores between 5 terminal IAs and 5 sidewall IAs. No strong correlation exists between vortex core characteristics and geometric or hemodynamic characteristics of IAs. Statistical independence suggests this proposed method may provide novel IA information. However, threshold values used to determine the vortex core regions and resolution of velocity data influenced analysis outcomes and have to be addressed in future studies. In conclusions, preliminary results show that the proposed methodology may help give novel insight toward aneurismal flow characteristic and help in future risk assessment given more developments.
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50
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Cai J, Wu D, Mo Y, Wang A, Hu S, Ren L. Comparison of extracranial artery stenosis and cerebral blood flow, assessed by quantitative magnetic resonance, using digital subtraction angiography as the reference standard. Medicine (Baltimore) 2016; 95:e5370. [PMID: 27861368 PMCID: PMC5120925 DOI: 10.1097/md.0000000000005370] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Extracranial arteriosclerosis usually indicates a high risk of ischemic stroke. In the past, a clinical decision following diagnosis was dependent on the percentage of vessel stenosis determined by an invasive technique. We aimed to develop a quantitative magnetic resonance (QMR) technique to evaluate artery structure and cerebral hemodynamics noninvasively.QMR and digital subtraction angiography (DSA) were performed in 67 patients with suspected cerebral vascular disease at our hospital. Accuracy, sensitivity, positive predictive values (PPVs), negative predictive values (NPVs), and Pearson correlation coefficient of QMR were calculated and compared for the detection and measurement of vascular stenoses using DSA as a gold standard. For patients with unilateral artery stenosis, quantitative cerebral blood flow (CBF) was measured by QMR in ipsilateral and contralateral hemispheres.Among 67 subjects (male 54, female 12), 201 stenoses were detected by QMR and DSA. QMR measuring the degree of stenosis and lesion length was in good correlation with the results obtained by DSA (r = 0.845, 0.721, respectively). As for artery stenosis, PPV and NPV of QMR were 89.55% and 95.71%, respectively. As for severe stenosis, sensitivity and specificity of QMR were 82.3% and 86.0% with DSA as a reference. For subjects with unilateral carotid stenosis, CBF in basal ganglia decreased significantly (P < 0.001) compared with the contralateral one in symptomatic and asymptomatic groups. For subjects with moderate stenosis (50-79%), CBF of temporal and basal ganglia was decreased compared with the contralateral ganglia. However, CBF in subjects with severe stenosis or occlusion in the basal ganglia was mildly elevated compared with the contralateral ganglia (P < 0.001).In our study, a good correlation was found between QMR and DSA when measuring artery stenosis and CBF. QMR may become an important method for measuring artery stenosis and cerebral hemodynamics in the future.
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Affiliation(s)
- Jingjing Cai
- Department of Neurology, The Affiliated College Shenzhen Second People's Hospital, Anhui Medical University, Hefei, Anhui province
- Department of Neurology, The First Affiliated Hospital of Shenzhen University
| | - Dan Wu
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong Province
| | - Yongqian Mo
- Department of Neurology, The First Affiliated Hospital of Shenzhen University
| | - Anxin Wang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Shiyu Hu
- Department of Neurology, The First Affiliated Hospital of Shenzhen University
| | - Lijie Ren
- Department of Neurology, The Affiliated College Shenzhen Second People's Hospital, Anhui Medical University, Hefei, Anhui province
- Department of Neurology, The First Affiliated Hospital of Shenzhen University
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