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Birnefeld J, Petersson K, Wåhlin A, Eklund A, Birnefeld E, Qvarlander S, Haney M, Malm J, Zarrinkoob L. Cerebral Blood Flow Assessed with Phase-contrast Magnetic Resonance Imaging during Blood Pressure Changes with Noradrenaline and Labetalol: A Trial in Healthy Volunteers. Anesthesiology 2024; 140:669-678. [PMID: 37756527 DOI: 10.1097/aln.0000000000004775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
BACKGROUND Adequate cerebral perfusion is central during general anesthesia. However, perfusion is not readily measured bedside. Clinicians currently rely mainly on mean arterial pressure (MAP) as a surrogate, even though the relationship between blood pressure and cerebral blood flow is not well understood. The aim of this study was to apply phase-contrast magnetic resonance imaging to characterize blood flow responses in healthy volunteers to commonly used pharmacologic agents that increase or decrease arterial blood pressure. METHODS Eighteen healthy volunteers aged 30 to 50 yr were investigated with phase-contrast magnetic resonance imaging. Intra-arterial blood pressure monitoring was used. First, intravenous noradrenaline was administered to a target MAP of 20% above baseline. After a wash-out period, intravenous labetalol was given to a target MAP of 15% below baseline. Cerebral blood flow was measured using phase-contrast magnetic resonance imaging and defined as the sum of flow in the internal carotid arteries and vertebral arteries. Cardiac output (CO) was defined as the flow in the ascending aorta. RESULTS Baseline median cerebral blood flow was 772 ml/min (interquartile range, 674 to 871), and CO was 5,874 ml/min (5,199 to 6,355). The median dose of noradrenaline was 0.17 µg · kg-1 · h-1 (0.14 to 0.22). During noradrenaline infusion, cerebral blood flow decreased to 705 ml/min (606 to 748; P = 0.001), and CO decreased to 4,995 ml/min (4,705 to 5,635; P = 0.01). A median dose of labetalol was 120 mg (118 to 150). After labetalol boluses, cerebral blood flow was unchanged at 769 ml/min (734 to 900; P = 0.68). CO increased to 6,413 ml/min (6,056 to 7,464; P = 0.03). CONCLUSIONS In healthy, awake subjects, increasing MAP using intravenous noradrenaline decreased cerebral blood flow and CO. These data do not support inducing hypertension with noradrenaline to increase cerebral blood flow. Cerebral blood flow was unchanged when decreasing MAP using labetalol. EDITOR’S PERSPECTIVE
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Affiliation(s)
- Johan Birnefeld
- Department of Clinical Sciences, Neurosciences, Umeå University, Umeå, Sweden
| | - Karl Petersson
- Department of Surgical and Perioperative Sciences, Anesthesiology and Intensive Care Medicine Unit, Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Departments of Radiation Sciences, Biomedical Engineering and Applied Physics and Electronics and Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Departments of Radiation Sciences, Biomedical Engineering and Applied Physics and Electronics, Umeå University, Umeå, Sweden
| | - Elin Birnefeld
- Department of Surgical and Perioperative Sciences, Anesthesiology and Intensive Care Medicine Unit, Umeå University, Umeå, Sweden
| | - Sara Qvarlander
- Department of Radiation Sciences, Biomedical Engineering, Umeå University, Umeå, Sweden
| | - Michael Haney
- Department of Surgical and Perioperative Sciences, Anesthesiology and Intensive Care Medicine Unit, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Sciences, Neurosciences, Umeå University, Umeå, Sweden
| | - Laleh Zarrinkoob
- Department of Surgical and Perioperative Sciences, Anesthesiology and Intensive Care Medicine Unit, Umeå University, Umeå, Sweden
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Kihlstedt CJ, Malm J, Fasano A, Bäckström D. Freezing of gait in idiopathic normal pressure hydrocephalus. Fluids Barriers CNS 2024; 21:22. [PMID: 38454478 PMCID: PMC10921745 DOI: 10.1186/s12987-024-00522-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 02/14/2024] [Indexed: 03/09/2024] Open
Abstract
BACKGROUND Reports of freezing of gait (FoG) in idiopathic normal pressure hydrocephalus (iNPH) are few and results are variable. This study's objective was to evaluate the frequency of FoG in a large cohort of iNPH patients, identify FoG-associated factors, and assess FoG's responsiveness to shunt surgery. METHODS Videotaped standardized gait protocols with iNPH patients pre- and post-shunt surgery (n = 139; median age 75 (71-79) years; 48 women) were evaluated for FoG episodes by two observers (Cohens kappa = 0.9, p < 0.001). FoG episodes were categorized. Mini-mental state examination (MMSE) and MRI white matter hyperintensities (WMH) assessment using the Fazekas scale were performed. CSF was analyzed for Beta-amyloid, Tau, and Phospho-tau. Patients with and without FoG were compared. RESULTS Twenty-two patients (16%) displayed FoG at baseline, decreasing to seven (8%) after CSF shunt surgery (p = 0.039). The symptom was most frequently exhibited during turning (n = 16, 73%). Patients displaying FoG were older (77.5 vs. 74.6 years; p = 0.029), had a slower walking speed (0.59 vs. 0.89 m/s; p < 0.001), a lower Tinetti POMA score (6.8 vs. 10.8; p < 0.001), lower MMSE score (21.3 vs. 24.0; p = 0.031), and longer disease duration (4.2 vs. 2.3 years; p < 0.001) compared to patients not displaying FoG. WMH or CSF biomarkers did not differ between the groups. CONCLUSIONS FoG is occurring frequently in iNPH patients and may be considered a typical feature of iNPH. FoG in iNPH was associated with higher age, longer disease duration, worse cognitive function, and a more unstable gait. Shunt surgery seems to improve the symptom.
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Affiliation(s)
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Alfonso Fasano
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, UHN, Toronto, ON, Canada
- Division of Neurology, University of Toronto, Toronto, ON, Canada
- Krembil Brain Institute, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - David Bäckström
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden.
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Eklund SA, Israelsson H, Brunström M, Forsberg K, Malm J. 10-year mortality, causes of death and cardiovascular comorbidities in idiopathic normal pressure hydrocephalus. J Neurol 2024; 271:1311-1319. [PMID: 37917232 PMCID: PMC10896765 DOI: 10.1007/s00415-023-12067-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/13/2023] [Accepted: 10/14/2023] [Indexed: 11/04/2023]
Abstract
OBJECTIVE The objective was to investigate 10-year mortality, causes of death and cardiovascular comorbidity in idiopathic normal pressure hydrocephalus (iNPH) and to evaluate their mutual associations. METHODS This prospective cohort study included 176 CSF-shunted iNPH patients, and 368 age- and sex-matched controls. At inclusion, participants were medically examined, had blood analyzed and answered a questionnaire. The vascular comorbidities investigated were smoking, diabetes, body mass index, blood pressure (BP), hyperlipidemia, kidney function, atrial fibrillation and, cerebro- and cardiovascular disease. RESULTS Survival was observed for a mean period of 10.3 ± 0.84 years. Shunted iNPH patients had an increased risk of death compared to controls (hazard ratio (HR) = 2.5, 95% CI 1.86-3.36; p < 0.001). After 10 years, 50% (n = 88) of iNPH patients and 24% (n = 88) of the controls were dead (p < 0.001). The risk of dying from cardiovascular disease, falls and neurological diseases were higher in iNPH (p < 0.05). The most common cause of death in iNPH was cardiovascular diseases (14% vs 7% for controls). Seven out of nine iNPH dying from falls had subdural hematomas. Systolic BP (HR = 0.985 95% CI 0.972-0.997, p = 0.018), atrial fibrillation (HR = 2.652, 95% CI 1.506-4.872, p < 0.001) and creatinine (HR = 1.018, 95% CI 1.010-1.027, p < 0.001) were independently associated with mortality for iNPH. DISCUSSION This long-term and population-matched cohort study indicates that in spite of CSF-shunt treatment, iNPH has shorter life expectancy. It may be important to treat iNPH in supplementary ways to reduce mortality. Both cardiovascular comorbidities and lethal falls are contributing to the excess mortality in iNPH and reducing these preventable risks should be an established part of the treatment plan.
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Affiliation(s)
- Sanna A Eklund
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden.
| | - Hanna Israelsson
- Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Mattias Brunström
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - Karin Forsberg
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
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Björnfot C, Eklund A, Larsson J, Hansson W, Birnefeld J, Garpebring A, Qvarlander S, Koskinen LOD, Malm J, Wåhlin A. Cerebral arterial stiffness is linked to white matter hyperintensities and perivascular spaces in older adults - A 4D flow MRI study. J Cereb Blood Flow Metab 2024:271678X241230741. [PMID: 38315044 DOI: 10.1177/0271678x241230741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
White matter hyperintensities (WMH), perivascular spaces (PVS) and lacunes are common MRI features of small vessel disease (SVD). However, no shared underlying pathological mechanism has been identified. We investigated whether SVD burden, in terms of WMH, PVS and lacune status, was related to changes in the cerebral arterial wall by applying global cerebral pulse wave velocity (gcPWV) measurements, a newly described marker of cerebral vascular stiffness. In a population-based cohort of 190 individuals, 66-85 years old, SVD features were estimated from T1-weighted and FLAIR images while gcPWV was estimated from 4D flow MRI data. Additionally, the gcPWV's stability to variations in field-of-view was analyzed. The gcPWV was 10.82 (3.94) m/s and displayed a significant correlation to WMH and white matter PVS volume (r = 0.29, p < 0.001; r = 0.21, p = 0.004 respectively from nonparametric tests) that persisted after adjusting for age, blood pressure variables, body mass index, ApoB/A1 ratio, smoking as well as cerebral pulsatility index, a previously suggested early marker of SVD. The gcPWV displayed satisfactory stability to field-of-view variations. Our results suggest that SVD is accompanied by changes in the cerebral arterial wall that can be captured by considering the velocity of the pulse wave transmission through the cerebral arterial network.
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Affiliation(s)
- Cecilia Björnfot
- Department of Diagnostics and Intervention, Radiation Physics, Biomedical Engineering, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Diagnostics and Intervention, Radiation Physics, Biomedical Engineering, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Jenny Larsson
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - William Hansson
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Johan Birnefeld
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Anders Garpebring
- Department of Diagnostics and Intervention, Umeå University, Umeå, Sweden
| | - Sara Qvarlander
- Department of Diagnostics and Intervention, Radiation Physics, Biomedical Engineering, Umeå University, Umeå, Sweden
| | - Lars-Owe D Koskinen
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Diagnostics and Intervention, Radiation Physics, Biomedical Engineering, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
- Department of Applied Physics and Electronics, Umeå University, Umeå, Sweden
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Hansson W, Johansson E, Birgander R, Eklund A, Malm J. Cerebral Microbleeds-Long-Term Outcome After Cerebrospinal Fluid Shunting in Idiopathic Normal Pressure Hydrocephalus. Neurosurgery 2023; 93:300-308. [PMID: 36853021 DOI: 10.1227/neu.0000000000002409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 12/14/2022] [Indexed: 03/01/2023] Open
Abstract
BACKGROUND Cerebral microbleeds (CMBs) are common in idiopathic normal pressure hydrocephalus (INPH) and have been suggested as radiological markers of a brain prone to bleeding. The presence of CMBs might be relevant when selecting patients for shunt surgery. OBJECTIVE To evaluate whether CMBs increases long-term risk of hemorrhagic complications and mortality or affects outcomes after cerebrospinal fluid shunt surgery in a cohort of patients with INPH. METHODS One hundred and forty nine shunted patients with INPH (mean age, 73 years) were investigated with MRI (T2* or susceptibility-weighted imaging sequences) preoperatively. CMBs were scored with the Microbleed Anatomic Rating Scale. Patients were observed for a mean of 6.5 years (range 2 weeks to 13 years) after surgery. Hemorrhagic events and death were noted. Improvement in gait was evaluated 3 to 6 months after surgery. RESULTS At baseline, 74 patients (50%) had CMBs. During follow-up, 7 patients (5%) suffered a hemorrhagic stroke and 43 (29%) suffered a subdural hematoma/hygroma with a median time from surgery of 30.2 months (IQR 50). Overall, having CMBs was not associated with suffering a subdural hematoma/hygroma or hemorrhagic stroke during follow-up with 1 exception that an extensive degree of CMBs (≥50 CMB) was more common in patients suffering a hemorrhagic stroke ( P = .03). CMBs were associated with increased mortality ( P = .02, Kaplan-Meier, log-rank test). The presence of CMBs did not affect gait outcome ( P = .28). CONCLUSION CMBs were associated with hemorrhagic stroke and mortality. CMBs do not seem to reduce the possibility of gait improvement after shunt surgery or contribute to the risk of hemorrhagic complications regarding subdural hematoma or hygroma.
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Affiliation(s)
- William Hansson
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Elias Johansson
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | | | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
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Luciano M, Holubkov R, Williams MA, Malm J, Nagel S, Moghekar A, Eklund A, Zwimpfer T, Katzen H, Hanley DF, Hamilton MG. Placebo-Controlled Effectiveness of Idiopathic Normal Pressure Hydrocephalus Shunting: A Randomized Pilot Trial. Neurosurgery 2023; 92:481-489. [PMID: 36700738 PMCID: PMC9904195 DOI: 10.1227/neu.0000000000002225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 09/11/2022] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Multiple prospective nonrandomized studies have shown 60% to 70% of patients with idiopathic normal pressure hydrocephalus (iNPH) improve with shunt surgery, but multicenter placebo-controlled trial data are necessary to determine its effectiveness. OBJECTIVE To evaluate the effectiveness of cerebrospinal fluid shunting in iNPH through comparison of open vs placebo shunting groups at 4 months using a pilot study. METHODS Patients were randomized to a Codman Certas Plus valve (Integra LifeSciences) set at 4 (open shunt group) or 8 ("virtual off"; placebo group). Patients and assessors were blinded to treatment group. The primary outcome measure was 10-m gait velocity. Secondary outcome measures included functional scales for bladder control, activities of daily living, depression, and quality of life. Immediately after 4-month evaluation, all shunts were adjusted in a blinded fashion to an active setting and followed to 12 months after shunting. RESULTS A total of 18 patients were randomized. At the 4-month evaluation, gait velocity increased by 0.28 ± 0.28 m/s in the open shunt group vs 0.04 ± 0.17 m/s in the placebo group. The estimated treatment difference was 0.22 m/s ([ P = .071], 95% CI -0.02 to 0.46). Overactive Bladder Short Form symptom bother questionnaire significantly improved in open shunt vs placebo ( P = .007). The 4-month treatment delay did not reduce the subsequent response to active shunting, nor did it increase the adverse advents rate at 12 months. CONCLUSION This multicenter, randomized pilot study demonstrates the effectiveness, safety, and feasibility of a placebo-controlled trial in iNPH, and found a trend suggesting gait velocity improves more in the open shunt group than in the placebo group.
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Affiliation(s)
- Mark Luciano
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Adult Hydrocephalus Clinical Research Network, Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Richard Holubkov
- Adult Hydrocephalus Clinical Research Network, Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Michael A. Williams
- Adult Hydrocephalus Clinical Research Network, Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Departments of Neurology and Neurological Surgery, University of Washington School of Medicine, Seattle, Washington, USA
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Sean Nagel
- Adult Hydrocephalus Clinical Research Network, Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Center for Neurological Restoration, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Neurosurgery, Cleveland Clinic, Cleveland, Ohio, USA
| | - Abhay Moghekar
- Adult Hydrocephalus Clinical Research Network, Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Department of Neurology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Anders Eklund
- Department of Radiation Sciences, Biomedical Engineering, Umeå University, Umeå, Sweden
| | - Thomas Zwimpfer
- Adult Hydrocephalus Clinical Research Network, Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Division of Neurosurgery, Department of Surgery, University of British Columbia, Vancouver, Canada
| | - Heather Katzen
- Adult Hydrocephalus Clinical Research Network, Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Department of Neurology, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Daniel F. Hanley
- Department of Neurology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Mark G. Hamilton
- Adult Hydrocephalus Clinical Research Network, Department of Pediatrics, Division of Critical Care, University of Utah School of Medicine, Salt Lake City, Utah, USA
- Division of Neurosurgery, Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Canada
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Cadenas J, Poulsen LC, Nikiforov D, Grøndahl ML, Kumar A, Bahnu K, Englund ALM, Malm J, Marko-Varga G, Pla I, Sanchez A, Pors SE, Andersen CY. Regulation of human oocyte maturation in vivo during the final maturation of follicles. Hum Reprod 2023; 38:686-700. [PMID: 36762771 DOI: 10.1093/humrep/dead024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 01/03/2023] [Indexed: 02/11/2023] Open
Abstract
STUDY QUESTION Which substances and signal transduction pathways are potentially active downstream to the effect of FSH and LH in the regulation of human oocyte maturation in vivo? SUMMARY ANSWER The regulation of human oocyte maturation appears to be a multifactorial process in which several different signal transduction pathways are active. WHAT IS KNOWN ALREADY Many studies in animal species have provided insight into the mechanisms that govern the final maturation of oocytes. Currently, these studies have identified several different mechanisms downstream to the effects of FSH and LH. Some of the identified mechanisms include the regulation of cAMP/cGMP levels in oocytes involving C-type natriuretic peptide (CNP), effects of epidermal growth factor (EGF)-related peptides such as amphiregulin (AREG) and/or epiregulin (EREG), effect of TGF-β family members including growth differentiation factor 9 (GDF9) and morphogenetic protein 15 (BMP15), activins/inhibins, follicular fluid meiosis activating sterol (FF-MAS), the growth factor midkine (MDK), and several others. However, to what extent these pathways and mechanisms are active in humans in vivo is unknown. STUDY DESIGN, SIZE, DURATION This prospective cohort study included 50 women undergoing fertility treatment in a standard antagonist protocol at a university hospital affiliated fertility clinic in 2016-2018. PARTICIPANTS/MATERIALS, SETTING, METHODS We evaluated the substances and signalling pathways potentially affecting human oocyte maturation in follicular fluid (FF) and granulosa cells (GCs) collected at five time points during the final maturation of follicles. Using ELISA measurement and proteomic profiling of FF and whole genome gene expression in GC, the following substances and their signal transduction pathways were collectively evaluated: CNP, the EGF family, inhibin-A, inhibin-B, activins, FF-MAS, MDK, GDF9, and BMP15. MAIN RESULTS AND THE ROLE OF CHANCE All the evaluated substances and signal transduction pathways are potentially active in the regulation of human oocyte maturation in vivo except for GDF9/BMP15 signalling. In particular, AREG, inhibins, and MDK were significantly upregulated during the first 12-17 h after initiating the final maturation of follicles and were measured at significantly higher concentrations than previously reported. Additionally, the genes regulating FF-MAS synthesis and metabolism were significantly controlled in favour of accumulation during the first 12-17 h. In contrast, concentrations of CNP were low and did not change during the process of final maturation of follicles, and concentrations of GDF9 and BMP15 were much lower than reported in small antral follicles, suggesting a less pronounced influence from these substances. LARGE SCALE DATA None. LIMITATIONS, REASONS FOR CAUTION Although GC and cumulus cells have many similar features, it is a limitation of the current study that information for the corresponding cumulus cells is not available. However, we seldom recovered a cumulus-oocyte complex during the follicle aspiration from 0 to 32 h. WIDER IMPLICATIONS OF THE FINDINGS Delineating the mechanisms governing the regulation of human oocyte maturation in vivo advances the possibility of developing a platform for IVM that, as for most other mammalian species, results in healthy offspring with good efficacy. Mimicking the intrafollicular conditions during oocyte maturation in vivo in small culture droplets during IVM may enhance oocyte nuclear and cytoplasmic maturation. The primary outlook for such a method is, in the context of fertility preservation, to augment the chances of achieving biological children after a cancer treatment by subjecting oocytes from small antral follicles to IVM. Provided that aspiration of oocytes from small antral follicles in vivo can be developed with good efficacy, IVM may be applied to infertile patients on a larger scale and can provide a cheap alternative to conventional IVF treatment with ovarian stimulation. Successful IVM has the potential to change current established techniques for infertility treatment. STUDY FUNDING/COMPETING INTEREST(S) This research was supported by the University Hospital of Copenhagen, Rigshospitalet, the Independent Research Fund Denmark (grant number 0134-00448), and the Interregional EU-sponsored ReproUnion network. There are no conflicts of interest to be declared.
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Affiliation(s)
- J Cadenas
- Laboratory of Reproductive Biology, Juliane Marie Centre for Women, Children and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark
| | - L C Poulsen
- Zealand Fertility Clinic, Zealand University Hospital, Køge, Denmark
| | - D Nikiforov
- Laboratory of Reproductive Biology, Juliane Marie Centre for Women, Children and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark
| | - M L Grøndahl
- The Fertility Clinic, Copenhagen University Hospital, Herlev Hospital, Herlev, Denmark
| | - A Kumar
- Ansh Labs LLC, Webster, TX, USA
| | - K Bahnu
- Ansh Labs LLC, Webster, TX, USA
| | - A L M Englund
- Zealand Fertility Clinic, Zealand University Hospital, Køge, Denmark
| | - J Malm
- Section for Clinical Chemistry, Department of Translational Medicine, Lund University, Skåne University Hospital Malmö, Malmö, Sweden.,Department of Biomedical Engineering, Clinical Protein Science & Imaging, Biomedical Centre, Lund University, Lund, Sweden
| | - G Marko-Varga
- Department of Biomedical Engineering, Clinical Protein Science & Imaging, Biomedical Centre, Lund University, Lund, Sweden
| | - I Pla
- Section for Clinical Chemistry, Department of Translational Medicine, Lund University, Skåne University Hospital Malmö, Malmö, Sweden.,Department of Biomedical Engineering, Clinical Protein Science & Imaging, Biomedical Centre, Lund University, Lund, Sweden
| | - A Sanchez
- Section for Clinical Chemistry, Department of Translational Medicine, Lund University, Skåne University Hospital Malmö, Malmö, Sweden.,Department of Biomedical Engineering, Clinical Protein Science & Imaging, Biomedical Centre, Lund University, Lund, Sweden
| | - S E Pors
- Laboratory of Reproductive Biology, Juliane Marie Centre for Women, Children and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark
| | - C Yding Andersen
- Laboratory of Reproductive Biology, Juliane Marie Centre for Women, Children and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark.,Faculty of Health and Medical Science, Copenhagen University, Copenhagen, Denmark
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9
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Woldmar N, Schwendenwein A, Kuras M, Szeitz B, Boettiger K, Tisza A, László V, Reiniger L, Bagó AG, Szállási Z, Moldvay J, Szász AM, Malm J, Horvatovich P, Pizzatti L, Domont GB, Rényi-Vámos F, Hoetzenecker K, Hoda MA, Marko-Varga G, Schelch K, Megyesfalvi Z, Rezeli M, Döme B. Proteomic analysis of brain metastatic lung adenocarcinoma reveals intertumoral heterogeneity and specific alterations associated with the timing of brain metastases. ESMO Open 2023; 8:100741. [PMID: 36527824 PMCID: PMC10024110 DOI: 10.1016/j.esmoop.2022.100741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 09/07/2022] [Accepted: 11/02/2022] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Brain metastases are associated with considerable negative effects on patients' outcome in lung adenocarcinoma (LADC). Here, we investigated the proteomic landscape of primary LADCs and their corresponding brain metastases. MATERIALS AND METHODS Proteomic profiling was conducted on 20 surgically resected primary and brain metastatic LADC samples via label-free shotgun proteomics. After sample processing, peptides were analyzed using an Ultimate 3000 pump coupled to a QExactive HF-X mass spectrometer. Raw data were searched using PD 2.4. Further data analyses were carried out using Perseus, RStudio and GraphPad Prism. Proteomic data were correlated with clinical and histopathological parameters and the timing of brain metastases. Mass spectrometry-based proteomic data are available via ProteomeXchange with identifier PXD027259. RESULTS Out of the 6821 proteins identified and quantified, 1496 proteins were differentially expressed between primary LADCs and corresponding brain metastases. Pathways associated with the immune system, cell-cell/matrix interactions and migration were predominantly activated in the primary tumors, whereas pathways related to metabolism, translation or vesicle formation were overrepresented in the metastatic tumors. When comparing fast- versus slow-progressing patients, we found 454 and 298 differentially expressed proteins in the primary tumors and brain metastases, respectively. Metabolic reprogramming and ribosomal activity were prominently up-regulated in the fast-progressing patients (versus slow-progressing individuals), whereas expression of cell-cell interaction- and immune system-related pathways was reduced in these patients and in those with multiple brain metastases. CONCLUSIONS This is the first comprehensive proteomic analysis of paired primary tumors and brain metastases of LADC patients. Our data suggest a malfunction of cellular attachment and an increase in ribosomal activity in LADC tissue, promoting brain metastasis. The current study provides insights into the biology of LADC brain metastases and, moreover, might contribute to the development of personalized follow-up strategies in LADC.
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Affiliation(s)
- N Woldmar
- Department of Biomedical Engineering, Lund University, Lund, Sweden; Laboratory of Molecular Biology and Proteomics of Blood/LADETEC, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - A Schwendenwein
- Department of Thoracic Surgery, Medical University Vienna, Vienna, Austria
| | - M Kuras
- Section for Clinical Chemistry, Department of Translational Medicine, Lund University, Skåne University Hospital Malmö, Malmö, Sweden
| | - B Szeitz
- Division of Oncology, Department of Internal Medicine and Oncology, Semmelweis University, Budapest, Hungary
| | - K Boettiger
- Department of Thoracic Surgery, Medical University Vienna, Vienna, Austria
| | - A Tisza
- National Korányi Institute of Pulmonology, Budapest, Hungary; Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - V László
- Department of Thoracic Surgery, Medical University Vienna, Vienna, Austria; National Korányi Institute of Pulmonology, Budapest, Hungary
| | - L Reiniger
- Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary; Department of Pathology, Forensic and Insurance Medicine, MTA-SE NAP, Brain Metastasis Research Group, Hungarian Academy of Sciences, Budapest, Hungary
| | - A G Bagó
- Department of Neurooncology, National Institute of Clinical Neurosciences, Budapest, Hungary
| | - Z Szállási
- Department of Pathology, Forensic and Insurance Medicine, MTA-SE NAP, Brain Metastasis Research Group, Hungarian Academy of Sciences, Budapest, Hungary; Computational Health Informatics Program, Boston Children's Hospital, Harvard Medical School, Boston, USA; Danish Cancer Society Research Center, Copenhagen, Denmark
| | - J Moldvay
- National Korányi Institute of Pulmonology, Budapest, Hungary; Department of Pathology, Forensic and Insurance Medicine, MTA-SE NAP, Brain Metastasis Research Group, Hungarian Academy of Sciences, Budapest, Hungary
| | - A M Szász
- National Korányi Institute of Pulmonology, Budapest, Hungary; Department of Bioinformatics, Semmelweis University, Budapest, Hungary
| | - J Malm
- Section for Clinical Chemistry, Department of Translational Medicine, Lund University, Skåne University Hospital Malmö, Malmö, Sweden
| | - P Horvatovich
- Department of Analytical Biochemistry, Groningen Research Institute of Pharmacy, University of Groningen, Groningen, The Netherlands
| | - L Pizzatti
- Laboratory of Molecular Biology and Proteomics of Blood/LADETEC, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - G B Domont
- Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - F Rényi-Vámos
- National Korányi Institute of Pulmonology, Budapest, Hungary; Department of Thoracic Surgery, National Institute of Oncology-Semmelweis University, Budapest, Hungary
| | - K Hoetzenecker
- Department of Thoracic Surgery, Medical University Vienna, Vienna, Austria
| | - M A Hoda
- Department of Thoracic Surgery, Medical University Vienna, Vienna, Austria
| | - G Marko-Varga
- Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - K Schelch
- Department of Thoracic Surgery, Medical University Vienna, Vienna, Austria
| | - Z Megyesfalvi
- Department of Thoracic Surgery, Medical University Vienna, Vienna, Austria; National Korányi Institute of Pulmonology, Budapest, Hungary; Department of Thoracic Surgery, National Institute of Oncology-Semmelweis University, Budapest, Hungary
| | - M Rezeli
- Department of Biomedical Engineering, Lund University, Lund, Sweden.
| | - B Döme
- Department of Thoracic Surgery, Medical University Vienna, Vienna, Austria; Section for Clinical Chemistry, Department of Translational Medicine, Lund University, Skåne University Hospital Malmö, Malmö, Sweden; National Korányi Institute of Pulmonology, Budapest, Hungary; Department of Thoracic Surgery, National Institute of Oncology-Semmelweis University, Budapest, Hungary.
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10
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Eklund SA, Israelsson H, Carlberg B, Malm J. Vascular risk profiles for predicting outcome and long-term mortality in patients with idiopathic normal pressure hydrocephalus: comparison of clinical decision support tools. J Neurosurg 2023; 138:476-482. [PMID: 35901765 DOI: 10.3171/2022.4.jns22125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 04/25/2022] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Vascular risk factors (VRFs) may act synergistically, and clinical decision support tools (CDSTs) have been developed that present vascular risk as a summarized score. Because VRFs are a major issue in patients with idiopathic normal pressure hydrocephalus (INPH), a CDST may be useful in the diagnostic workup. The objective was to compare 4 CDSTs to determine which one most accurately predicts short-term outcome and 10-year mortality after CSF shunt surgery in INPH patients. METHODS One-hundred forty INPH patients who underwent CSF shunt surgery were included. For each patient, 4 CDST scores (Systematic Coronary Risk Evaluation-Older Persons [SCORE-OP], Framingham Risk Score [FRS], Revised Framingham Stroke Risk Profile, and Kiefer's Comorbidity Index [KCI]) were estimated. Short-term outcome (3 months after CSF shunt surgery) was defined on the basis of improvements in gait, Mini-Mental State Examination score, and modified Rankin Scale score. The 10-year mortality rate after surgery was noted. The CDSTs were compared by using Cox regression analysis, receiver operating characteristic curve analysis, and the chi-square test. RESULTS For 3 CDSTs, increased score was associated with increased risk of 10-year mortality. A 1-point increase in the FRS indicated a 2% higher risk of death within 10 years (HR 1.02, 95% CI 1.003-1.035, p = 0.021); SCORE-OP, 5% (HR 1.05, 95% CI 1.019-1.087, p = 0.002); and KCI, 12% (HR 1.12, 95% CI 1.03-1.219, p = 0.008). FRS predicted short-term outcome of surgery (p = 0.024). When the cutoff value was set to 32.5%, the positive predictive value was 80% and the negative predictive value was 48% (p = 0.012). CONCLUSIONS The authors recommend using FRS to predict short-term outcome and 10-year risk of mortality in INPH patients. The study indicated that extensive treatment of the risk factors of INPH may decrease risk of mortality. Clinical trial registration no.: NCT01850914 (ClinicalTrials.gov).
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Affiliation(s)
- Sanna A Eklund
- 1Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Hanna Israelsson
- 2Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden; and
| | - Bo Carlberg
- 3Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - Jan Malm
- 1Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
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11
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Bluett B, Ash E, Farheen A, Fasano A, Krauss JK, Maranzano A, Passaretti M, Tang‐Wai DF, Van Gerpen J, Alonso‐Canovas A, Youn J, Malm J, Martino D. Clinical Features of Idiopathic Normal Pressure Hydrocephalus: Critical Review of Objective Findings. Mov Disord Clin Pract 2023; 10:9-16. [PMID: 36704075 PMCID: PMC9847299 DOI: 10.1002/mdc3.13608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 09/07/2022] [Accepted: 09/23/2022] [Indexed: 11/07/2022] Open
Abstract
Background Idiopathic normal pressure hydrocephalus (iNPH) is characterized by the classic clinical triad of gait, cognitive, and urinary dysfunction, albeit incomplete in a relevant proportion of patients. The clinical findings and evolution of these symptoms have been variably defined in the literature. Objectives To evaluate how the phenomenology has been defined, assessed, and reported, we performed a critical review of the existing literature discussing the phenomenology of iNPH. The review also identified the instrumental tests most frequently used and the evolution of clinical and radiologic findings. Methods The review was divided into 3 sections based on gait, cognitive, and urinary dysfunction. Each section performed a literature search using the terms "idiopathic normal pressure hydrocephalus" (iNPH), with additional search terms used by each section separately. The number of articles screened, duplicates, those meeting the inclusion criteria, and the number of articles excluded were recorded. Findings were subsequently tallied and analyzed. Results A total of 1716 articles with the aforementioned search criteria were identified by the 3 groups. A total of 81 full-text articles were reviewed after the elimination of duplicates, articles that did not discuss phenomenological findings or instrumental testing of participants with iNPH prior to surgery, and articles with fewer than 10 participants. Conclusions "Wide-based gait" was the most common gait dysfunction identified. Cognitive testing varied significantly across articles, and ultimately a specific cognitive profile was not identified. Urodynamic testing found detrusor overactivity and "overactive bladder" as the most common symptom of urinary dysfunction.
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Affiliation(s)
- Brent Bluett
- Central California Movement DisordersPismo BeachCaliforniaUSA
| | - Elissa Ash
- Department of Neurology, Faculty of MedicineTel Aviv Sourasky Medical CenterTel AvivIsrael
| | - Amtul Farheen
- Department of NeurologyLebanon VA Medical CenterLebanonPennsylvaniaUSA
- Department of NeurologyPenn State Hershey Medical CenterHersheyPennsylvaniaUSA
| | - Alfonso Fasano
- Edmond J. Safra Program in Parkinson's DiseaseMorton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, University Health NetworkTorontoOntarioCanada
- Krembil Brain InstituteUniversity Health NetworkTorontoOntarioCanada
- Howard Cohen Normal Pressure Hydrocephalus ProgramUniversity Health Network, Toronto Western HospitalTorontoOntarioCanada
- Department of Medicine, Division of NeurologyUniversity of TorontoTorontoOntarioCanada
| | | | - Alessio Maranzano
- Department of NeurologyIstituto Auxologico Italiano IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico)MilanItaly
- Department of Pathophysiology and TransplantationUniversity of MilanMilanItaly
| | | | - David F. Tang‐Wai
- Krembil Brain InstituteUniversity Health NetworkTorontoOntarioCanada
- Howard Cohen Normal Pressure Hydrocephalus ProgramUniversity Health Network, Toronto Western HospitalTorontoOntarioCanada
- Department of Medicine, Division of NeurologyUniversity of TorontoTorontoOntarioCanada
- University Health Network Memory ClinicToronto Western HospitalTorontoOntarioCanada
| | - Jay Van Gerpen
- Department of NeurologyUniversity of Alabama at BirminghamHuntsvilleAlabamaUSA
| | - Araceli Alonso‐Canovas
- Movement Disorders Unit. Neurology DepartmentHospital Universitario Ramón y CajalMadridSpain
| | - Jinyoung Youn
- Department of NeurologySamsung Medical Center, Sungkyunkwan University School of MedicineSeoulSouth Korea
| | - Jan Malm
- Department of Clinical NeuroscienceUmeå UniversityUmeåSweden
| | - Davide Martino
- Department of Clinical Neurosciences and Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
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12
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Holmgren M, Holmlund P, Støverud KH, Zarrinkoob L, Wåhlin A, Malm J, Eklund A. Prediction of cerebral perfusion pressure during carotid surgery - A computational fluid dynamics approach. Clin Biomech (Bristol, Avon) 2022; 100:105827. [PMID: 36435076 DOI: 10.1016/j.clinbiomech.2022.105827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 10/09/2022] [Accepted: 11/18/2022] [Indexed: 11/21/2022]
Abstract
BACKGROUND Maintaining cerebral perfusion pressure in the brain when a carotid artery is closed during vascular surgery is critical for avoiding intraoperative hypoperfusion and risk of ischemic stroke. Here we propose and evaluate a method based on computational fluid dynamics for predicting patient-specific cerebral perfusion pressures at carotid clamping during carotid endarterectomy. METHODS The study consisted of 22 patients with symptomatic carotid stenosis who underwent carotid endarterectomy (73 ± 5 years, 59-80 years, 17 men). The geometry of the circle of Willis was obtained preoperatively from computed tomography angiography and corresponding flow rates from four-dimensional flow magnetic resonance imaging. The patients were also classified as having a present or absent ipsilateral posterior communicating artery based on computed tomography angiography. The predicted mean stump pressures from computational fluid dynamics were compared with intraoperatively measured stump pressures from carotid endarterectomy. FINDINGS On group level, there was no difference between the predicted and measured stump pressures (-0.5 ± 13 mmHg, P = 0.86) and the pressures were correlated (r = 0.44, P = 0.039). Omitting two outliers, the correlation increased to r = 0.78 (P < 0.001) (-1.4 ± 8.0 mmHg, P = 0.45). Patients with a present ipsilateral posterior communicating artery (n = 8) had a higher measured stump pressure than those with an absent artery (n = 12) (P < 0.001). INTERPRETATION The stump pressure agreement indicates that the computational fluid dynamics approach was promising in predicting cerebral perfusion pressures during carotid clamping, which may prove useful in the preoperative planning of vascular interventions.
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Affiliation(s)
- Madelene Holmgren
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, SE 901 87 Umeå University, Umeå, Sweden..
| | - Petter Holmlund
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, SE 901 87 Umeå University, Umeå, Sweden
| | - Karen-Helene Støverud
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, SE 901 87 Umeå University, Umeå, Sweden.; Department of Health Research, SINTEF Digital, NO 7465 Trondheim, Norway
| | - Laleh Zarrinkoob
- Department of Clinical Science, Neurosciences, Umeå University, SE 901 87 Umeå, Sweden; Department of Surgical and Perioperative Sciences, Umeå University, SE 901 87 Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, SE 901 87 Umeå University, Umeå, Sweden.; Department of Applied Physics and Electronics, Umeå University, SE 901 87 Umeå, Sweden; Umeå Center for Functional Brain Imaging, Umeå University, SE 901 87 Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, SE 901 87 Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, SE 901 87 Umeå University, Umeå, Sweden.; Umeå Center for Functional Brain Imaging, Umeå University, SE 901 87 Umeå, Sweden
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13
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Vikner T, Karalija N, Eklund A, Malm J, Lundquist A, Gallewicz N, Dahlin M, Lindenberger U, Riklund K, Bäckman L, Nyberg L, Wåhlin A. 5-Year Associations among Cerebral Arterial Pulsatility, Perivascular Space Dilation, and White Matter Lesions. Ann Neurol 2022; 92:871-881. [PMID: 36054261 PMCID: PMC9804392 DOI: 10.1002/ana.26475] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 08/01/2022] [Accepted: 08/01/2022] [Indexed: 01/05/2023]
Abstract
OBJECTIVE High cerebral arterial pulsatility index (PI), white matter lesions (WMLs), enlarged perivascular spaces (PVSs), and lacunar infarcts are common findings in the elderly population, and considered indicators of small vessel disease (SVD). Here, we investigate the potential temporal ordering among these variables, with emphasis on determining whether high PI is an early or delayed manifestation of SVD. METHODS In a population-based cohort, 4D flow MRI data for cerebral arterial pulsatility was collected for 159 participants at baseline (age 64-68), and for 122 participants at follow-up 5 years later. Structural MRI was used for WML and PVS segmentation, and lacune identification. Linear mixed-effects (LME) models were used to model longitudinal changes testing for pairwise associations, and latent change score (LCS) models to model multiple relationships among variables simultaneously. RESULTS Longitudinal 5-year increases were found for WML, PVS, and PI. Cerebral arterial PI at baseline did not predict changes in WML or PVS volume. However, WML and PVS volume at baseline predicted 5-year increases in PI. This was shown for PI increases in relation to baseline WML and PVS volumes using LME models (R ≥ 0.24; p < 0.02 and R ≥ 0.23; p < 0.03, respectively) and LCS models ( β = 0.28; p = 0.015 and β = 0.28; p = 0.009, respectively). Lacunes at baseline were unrelated to PI. INTERPRETATION In healthy older adults, indicators of SVD are related in a lead-lag fashion, in which the expression of WML and PVS precedes increases in cerebral arterial PI. Hence, we propose that elevated PI is a relatively late manifestation, rather than a risk factor, for cerebral SVD. ANN NEUROL 2022;92:871-881.
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Affiliation(s)
- Tomas Vikner
- Department of Radiation SciencesUmeå UniversityUmeåSweden
| | - Nina Karalija
- Department of Radiation SciencesUmeå UniversityUmeåSweden
- Umeå Center for Functional Brain Imaging (UFBI)Umeå UniversityUmeåSweden
| | - Anders Eklund
- Department of Radiation SciencesUmeå UniversityUmeåSweden
- Umeå Center for Functional Brain Imaging (UFBI)Umeå UniversityUmeåSweden
| | - Jan Malm
- Department of Clinical Science, NeurosciencesUmeå UniversityUmeåSweden
| | - Anders Lundquist
- Umeå Center for Functional Brain Imaging (UFBI)Umeå UniversityUmeåSweden
- Department of Statistics, USBEUmeå UniversityUmeåSweden
| | | | - Magnus Dahlin
- Department of Radiation SciencesUmeå UniversityUmeåSweden
| | - Ulman Lindenberger
- Center for Lifespan PsychologyMax Planck Institute for Human DevelopmentBerlinGermany
- Max PlanckUCL Centre for Computational Psychiatry and Ageing ResearchBerlinGermany
- Max PlanckUCL Centre for Computational Psychiatry and Ageing ResearchLondonUK
| | - Katrine Riklund
- Department of Radiation SciencesUmeå UniversityUmeåSweden
- Umeå Center for Functional Brain Imaging (UFBI)Umeå UniversityUmeåSweden
| | - Lars Bäckman
- Ageing Research CenterKarolinska Institutet and Stockholm UniversityStockholmSweden
| | - Lars Nyberg
- Department of Radiation SciencesUmeå UniversityUmeåSweden
- Umeå Center for Functional Brain Imaging (UFBI)Umeå UniversityUmeåSweden
- Department of Integrative Medical Biology (IMB)Umeå UniversityUmeåSweden
| | - Anders Wåhlin
- Department of Radiation SciencesUmeå UniversityUmeåSweden
- Umeå Center for Functional Brain Imaging (UFBI)Umeå UniversityUmeåSweden
- Department of Applied Physics and ElectronicsUmeå UniversityUmeåSweden
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14
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Abstract
Alterations in cerebral blood flow are common in several neurological diseases among the elderly including stroke, cerebral small vessel disease, vascular dementia, and Alzheimer's disease. 4D flow magnetic resonance imaging (MRI) is a relatively new technique to investigate cerebrovascular disease, and makes it possible to obtain time-resolved blood flow measurements of the entire cerebral arterial venous vasculature and can be used to derive a repertoire of hemodynamic biomarkers indicative of cerebrovascular health. The information that can be obtained from one single 4D flow MRI scan allows both the investigation of aberrant flow patterns at a focal location in the vasculature as well as estimations of brain-wide disturbances in blood flow. Such focal and global hemodynamic biomarkers show the potential of being sensitive to impending cerebrovascular disease and disease progression and can also become useful during planning and follow-up of interventions aiming to restore a normal cerebral circulation. Here, we describe 4D flow MRI approaches for analyzing the cerebral vasculature. We then survey key hemodynamic biomarkers that can be reliably assessed using the technique. Finally, we highlight cerebrovascular diseases where one or multiple hemodynamic biomarkers are of central interest.
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Affiliation(s)
- Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Department of Applied Physics and Electronics, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science and Neurosciences, Umeå University, Umeå, Sweden
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15
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Grudet C, Lindqvist D, Malm J, Westrin Å, Ventorp F. 25(OH)D levels are decreased in patients with difficult-to-treat depression. Comprehensive Psychoneuroendocrinology 2022; 10:100126. [PMID: 35755210 PMCID: PMC9216441 DOI: 10.1016/j.cpnec.2022.100126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 02/07/2022] [Accepted: 02/07/2022] [Indexed: 12/01/2022] Open
Abstract
Objectives The aims of the study are i) to compare 25-hydroxyvitamin D (25(OH)D) levels between clinically depressed individuals with insufficient treatment response and healthy controls and ii) to test the association between 25(OH)D levels and different affective disorder diagnoses (i.e., major depressive disorder (MDD) single episode, MDD recurrent episode, chronic MDD, and dysthymia), as well as grade of suicidal ideation. Method We quantified serum 25(OH)D in 202 individuals with difficult-to-treat depression (DTD) and 41 healthy controls. Patients were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV-TR). ANCOVA was used to test differences in mean 25(OH)levels between depressed and controls, adjusting for sex, age, smoking, sampling season, ethnicity, somatic illness, and body mass index (BMI). Binary logistic regression models were used to test the association between depression and 25(OH)D levels. Results Patients with difficult-to-treat depression had significantly lower levels of 25(OH)D compared to healthy controls (ANCOVA, F = 4.89; p = 0.03). Thirty percent of the depressed patients were 25(OH)D deficient (<50 nmol/L) compared to 5% of the controls (Chi-squared test, χ2 = 11.38; p < 0.01). The odds for being depressed decreased significantly with 17% per 10 nmol/L increase of 25(OH)D (Binary logistic regression, p < 0.05). Limitations The cross-sectional design of the study precludes any conclusions about causality. A large part of the patients took psychotropic drugs and/or had somatic illnesses, which might have affected the results. Conclusion The results of the present study add to the body of evidence linking 25(OH)D deficiency and depression. Further investigations are warranted to better understand any clinical implications of this association. Lower 25(OH)D levels in difficult-to-treat depression versus healthy controls. No difference in 25(OH)D levels between different affective disorder diagnoses. No associations between 25(OH)D and suicidality.
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16
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Holmlund P, Støverud K, Wåhlin A, Wiklund U, Malm J, Jóhannesson G, Eklund A. Posture‐dependent collapse of the optic nerve subarachnoid space: a combined MRI and modeling study. Acta Ophthalmol 2022. [DOI: 10.1111/j.1755-3768.2022.098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
| | | | - Anders Wåhlin
- Radiation Sciences Umeå University Umeå Sweden
- Umeå Center for Functional Brain Imaging Umeå University Umeå Sweden
| | | | - Jan Malm
- Department of Clinical Sciences, Neurosciences Umeå University Umeå Sweden
| | - Gauti Jóhannesson
- Department of Clinical Sciences Ophthalmology Umeå University Umeå Sweden
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17
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Larsson J, Israelsson H, Eklund A, Lundin-Olsson L, Malm J. Falls and Fear of Falling in Shunted Idiopathic Normal Pressure Hydrocephalus—The Idiopathic Normal Pressure Hydrocephalus Comorbidity and Risk Factors Associated With Hydrocephalus Stud. Neurosurgery 2021. [DOI: 10.1093/neuros/nyab094_s137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Holmlund P, Støverud KH, Wåhlin A, Wiklund U, Malm J, Jóhannesson G, Eklund A. Author Response: Posture-Dependent Collapse of the Optic Nerve Subarachnoid Space: A Combined MRI and Modeling Study. Invest Ophthalmol Vis Sci 2021; 62:15. [PMID: 34932065 PMCID: PMC8709931 DOI: 10.1167/iovs.62.15.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Affiliation(s)
- Petter Holmlund
- Department of Radiation Sciences, Umeå University, Sweden.,E-mail:
| | | | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Sweden
| | - Urban Wiklund
- Department of Radiation Sciences, Umeå University, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Sweden
| | - Gauti Jóhannesson
- Department of Clinical Sciences, Ophthalmology, Umeå University, Sweden.,Wallenberg Centre for Molecular Medicine, Umeå University, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Sweden
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Malm J, Birnefeld J, Zarrinkoob L, Wåhlin A, Eklund A. Hemodynamic Disturbances in Posterior Circulation Stroke: 4D Flow Magnetic Resonance Imaging Added to Computed Tomography Angiography. Front Neurosci 2021; 15:656769. [PMID: 34658752 PMCID: PMC8514699 DOI: 10.3389/fnins.2021.656769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 08/18/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: A clinically feasible, non-invasive method to quantify blood flow, hemodynamics, and collateral flow in the vertebrobasilar arterial tree is missing. The objective of this study was to evaluate the feasibility of quantifying blood flow and blood flow patterns using 4D flow magnetic resonance imaging (MRI) in consecutive patients after an ischemic stroke in the posterior circulation. We also explore if 4D-flow, analyzed in conjunction with computed tomography angiography (CTA), has potential as a diagnostic tool in posterior circulation stroke. Methods: Twenty-five patients (mean age 62 years; eight women) with acute ischemic stroke in the posterior circulation were investigated. At admission, all patients were examined with CTA followed by MRI (4D flow MRI and diffusion-weighted sequences) at median 4 days after the presenting event. Based on the classification of Caplan, patients were divided into proximal/middle (n = 16) and distal territory infarcts (n = 9). Absolute and relative blood flow rates were calculated for internal carotid arteries (ICA), vertebral arteries (VA), basilar artery (BA), posterior cerebral arteries (P1 and P2), and the posterior communicating arteries (Pcom). In a control group consisting of healthy elderly, the 90th and 10th percentiles of flow were calculated in order to define normal, increased, or decreased blood flow in each artery. "Major hemodynamic disturbance" was defined as low BA flow and either low P2 flow or high Pcom flow. Various minor hemodynamic disturbances were also defined. Blood flow rates were compared between groups. In addition, a comprehensive analysis of each patient's blood flow profile was performed by assessing relative blood flow rates in each artery in conjunction with findings from CTA. Results: There was no difference in total cerebral blood flow between patients and controls [604 ± 117 ml/min vs. 587 ± 169 ml/min (mean ± SD), p = 0.39] or in total inflow to the posterior circulation (i.e., the sum of total VA and Pcom flows, 159 ± 63 ml/min vs. 164 ± 52 ml/min, p = 0.98). In individual arteries, there were no significant differences between patients and controls in absolute or relative flow. However, patients had larger interindividual relative flow variance in BA, P1, and P2 (p = 0.01, <0.01, and 0.02, respectively). Out of the 16 patients that had proximal/middle territory infarcts, nine had CTA findings in VA and/or BA generating five with major hemodynamic disturbance identified with 4D flow MRI. For those without CTA findings, seven had no or minor 4D flow MRI hemodynamic disturbance. Among nine patients with distal territory infarcts, one had major hemodynamic disturbances, while the remaining had minor disturbances. Conclusion: 4D flow MRI contributed to the identification of the patients who had major hemodynamic disturbances from the vascular pathologies revealed on CTA. We thus conclude that 4D flow MRI could add valuable hemodynamic information when used in conjunction with CTA.
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Affiliation(s)
- Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Johan Birnefeld
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Laleh Zarrinkoob
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden.,Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Centre for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
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20
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Abstract
Intracranial arterial stiffening is a potential early marker of emerging cerebrovascular dysfunction and could be mechanistically involved in disease processes detrimental to brain function via several pathways. A prominent consequence of arterial wall stiffening is the increased velocity at which the systolic pressure pulse wave propagates through the vasculature. Previous non-invasive measurements of the pulse wave propagation have been performed on the aorta or extracranial arteries with results linking increased pulse wave velocity to brain pathology. However, there is a lack of intracranial "target-organ" measurements. Here we present a 4D flow MRI method to estimate pulse wave velocity in the intracranial vascular tree. The method utilizes the full detectable branching structure of the cerebral vascular tree in an optimization framework that exploits small temporal shifts that exists between waveforms sampled at varying depths in the vasculature. The method is shown to be stable in an internal consistency test, and of sufficient sensitivity to robustly detect age-related increases in intracranial pulse wave velocity.
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Affiliation(s)
- Cecilia Björnfot
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Cecilia Björnfot, Department of Radiation Sciences, Umeå University, Umeå SE 901 87, Sweden.
| | | | - Sara Qvarlander
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
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21
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Vikner T, Eklund A, Karalija N, Malm J, Riklund K, Lindenberger U, Bäckman L, Nyberg L, Wåhlin A. Cerebral arterial pulsatility is linked to hippocampal microvascular function and episodic memory in healthy older adults. J Cereb Blood Flow Metab 2021; 41:1778-1790. [PMID: 33444091 PMCID: PMC8217890 DOI: 10.1177/0271678x20980652] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Microvascular damage in the hippocampus is emerging as a central cause of cognitive decline and dementia in aging. This could be a consequence of age-related decreases in vascular elasticity, exposing hippocampal capillaries to excessive cardiac-related pulsatile flow that disrupts the blood-brain barrier and the neurovascular unit. Previous studies have found altered intracranial hemodynamics in cognitive impairment and dementia, as well as negative associations between pulsatility and hippocampal volume. However, evidence linking features of the cerebral arterial flow waveform to hippocampal function is lacking. We used a high-resolution 4D flow MRI approach to estimate global representations of the time-resolved flow waveform in distal cortical arteries and in proximal arteries feeding the brain in healthy older adults. Waveform-based clustering revealed a group of individuals featuring steep systolic onset and high amplitude that had poorer hippocampus-sensitive episodic memory (p = 0.003), lower whole-brain perfusion (p = 0.001), and weaker microvascular low-frequency oscillations in the hippocampus (p = 0.035) and parahippocampal gyrus (p = 0.005), potentially indicating compromised neurovascular unit integrity. Our findings suggest that aberrant hemodynamic forces contribute to cerebral microvascular and hippocampal dysfunction in aging.
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Affiliation(s)
- Tomas Vikner
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Nina Karalija
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Katrine Riklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
| | - Ulman Lindenberger
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany.,Max Planck, UCL Centre for Computational Psychiatry and Ageing Research, Berlin, Germany.,Max Planck, UCL Centre for Computational Psychiatry and Ageing Research, London, UK
| | - Lars Bäckman
- Ageing Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden
| | - Lars Nyberg
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden.,Department of Integrative Medical Biology (IMB), Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
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22
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Ryska P, Slezak O, Eklund A, Salzer J, Malm J, Zizka J. Variability of Normal Pressure Hydrocephalus Imaging Biomarkers with Respect to Section Plane Angulation: How Wrong a Radiologist Can Be? AJNR Am J Neuroradiol 2021; 42:1201-1207. [PMID: 33888457 DOI: 10.3174/ajnr.a7095] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 01/13/2021] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Systematic analysis of angulation-related variability of idiopathic normal pressure hydrocephalus imaging biomarkers has not been published yet. Our aim was to evaluate the variability of these radiologic biomarkers with respect to imaging plane angulation. MATERIALS AND METHODS Eighty subjects (35 with clinically confirmed idiopathic normal pressure hydrocephalus and 45 age- and sex-matched healthy controls) were prospectively enrolled in a 3T brain MR imaging study. Two independent readers assessed 12 radiologic idiopathic normal pressure hydrocephalus biomarkers on sections aligned parallel or perpendicular to the bicallosal, bicommissural, hypophysis-fastigium, and brain stem vertical lines, respectively. RESULTS Disproportionately enlarged subarachnoid space hydrocephalus, simplified callosal angle, frontal horn diameter, z-Evans Index, and cella media vertical width did not show significant systematic differences in any of 6 section plane combinations studied. The remaining 7 biomarkers (including the Evans Index and callosal angle) showed significant differences in up to 4 of 6 mutually compared section plane combinations. The values obtained from sections aligned with the brain stem vertical line (parallel to the posterior brain stem margin) showed the most deviating results from other section angulations. CONCLUSIONS Seven of 12 idiopathic normal pressure hydrocephalus biomarkers including the frequently used Evans Index and callosal angle showed statistically significant deviations when measured on sections whose angulations differed or did not comply with the proper section definition published in the original literature. Strict adherence to the methodology of idiopathic normal pressure hydrocephalus biomarker assessment is, therefore, essential to avoid an incorrect diagnosis. Increased radiologic and clinical attention should be paid to the biomarkers showing low angulation-related variability yet high specificity for idiopathic normal pressure hydrocephalus-related morphologic changes such as the z-Evans Index, frontal horn diameter, or disproportionately enlarged subarachnoid space hydrocephalus.
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Affiliation(s)
- P Ryska
- From the Department of Diagnostic Radiology (P.R., O.S.), University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - O Slezak
- From the Department of Diagnostic Radiology (P.R., O.S.), University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
- Department of Diagnostic Radiology (O.S.), Charles University, Faculty of Medicine in Hradec Kralove and University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - A Eklund
- Departments of Radiation Sciences (A.E.)
| | - J Salzer
- Pharmacology and Clinical Neuroscience (J.S., J.M.), Section of Neurology
| | - J Malm
- Pharmacology and Clinical Neuroscience (J.S., J.M.), Section of Neurology
| | - J Zizka
- Imaging and Functional Medicine (J.Z.), University Hospital of Umeå, Umeå, Sweden
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23
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Johansson E, Zarrinkoob L, Wåhlin A, Eklund A, Malm J. Diagnosing Carotid Near-Occlusion with Phase-Contrast MRI. AJNR Am J Neuroradiol 2021; 42:927-929. [PMID: 33707277 DOI: 10.3174/ajnr.a7076] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 12/07/2020] [Indexed: 11/07/2022]
Abstract
Carotid near-occlusion is a frequently overlooked diagnosis when CTA examinations are assessed in routine practice. To evaluate the potential value of phase-contrast MR imaging in identifying near-occlusion, we examined 9 carotid near-occlusions and 20 cases of conventional ≥50% carotid stenosis (mean stenosis degree, 65%) with phase-contrast MR imaging. Mean ICA flow was lower in near-occlusions (52 mL/min) than in conventional ≥50% stenosis (198 mL/min, P < .001). ICA flow of ≤110 mL/min was 100% sensitive and specific for near-occlusion. Phase-contrast MR imaging is a promising tool for diagnosing carotid near-occlusion.
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Affiliation(s)
- E Johansson
- Department of Clinical Science (E.J., L.Z., J.M.), Neurosciences, Umeå University, Umeå, Sweden
- Wallenberg Center for Molecular Medicine (E.J.), Umeå University, Umeå, Sweden
| | - L Zarrinkoob
- Department of Clinical Science (E.J., L.Z., J.M.), Neurosciences, Umeå University, Umeå, Sweden
- Department of Perioperative Sciences (L.Z.), Umeå University, Umeå, Sweden
| | - A Wåhlin
- Department of Radiation Sciences (A.W., A.E.), Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (A.W., A.E.), Umeå University, Umeå, Sweden
| | - A Eklund
- Department of Radiation Sciences (A.W., A.E.), Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (A.W., A.E.), Umeå University, Umeå, Sweden
| | - J Malm
- Department of Clinical Science (E.J., L.Z., J.M.), Neurosciences, Umeå University, Umeå, Sweden
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24
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Holmlund P, Støverud KH, Wåhlin A, Wiklund U, Malm J, Jóhannesson G, Eklund A. Posture-Dependent Collapse of the Optic Nerve Subarachnoid Space: A Combined MRI and Modeling Study. Invest Ophthalmol Vis Sci 2021; 62:26. [PMID: 33877263 PMCID: PMC8083083 DOI: 10.1167/iovs.62.4.26] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose We hypothesize that a collapse of the optic nerve subarachnoid space (ONSAS) in the upright posture may protect the eyes from large translamina cribrosa pressure differences (TLCPD) believed to play a role in various optic nerve diseases (e.g., glaucoma). In this study, we combined magnetic resonance imaging (MRI) and mathematical modeling to investigate this potential ONSAS collapse and its effects on the TLCPD. Methods First, we performed MRI on six healthy volunteers in 6° head-down tilt (HDT) and 13° head-up tilt (HUT) to assess changes in ONSAS volume (measured from the eye to the optic canal) with changes in posture. The volume change reflects optic nerve sheath (ONS) distensibility. Second, we used the MRI data and mathematical modeling to simulate ONSAS pressure and the potential ONSAS collapse in a 90° upright posture. Results The MRI showed a 33% decrease in ONSAS volume from the HDT to HUT (P < 0.001). In the upright posture, the simulations predicted an ONSAS collapse 25 mm behind lamina cribrosa, disrupting the pressure communication between the ONSAS and the intracranial subarachnoid space. The collapse reduced the simulated postural increase in TLCPD by roughly 1 mm Hg, although this reduction was highly sensitive to ONS distensibility, varying between 0 and 4.8 mm Hg when varying the distensibility by ± 1 SD. Conclusions The ONSAS volume along the optic nerve is posture dependent. The simulations supported the hypothesized ONSAS collapse in the upright posture and showed that even small changes in ONS stiffness/distensibility may affect the TLCPD.
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Affiliation(s)
- Petter Holmlund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | | | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Urban Wiklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Gauti Jóhannesson
- Department of Clinical Sciences, Ophthalmology, Umeå University, Umeå, Sweden.,Wallenberg Centre for Molecular Medicine, 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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25
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Larsson J, Israelsson H, Eklund A, Lundin-Olsson L, Malm J. Falls and Fear of Falling in Shunted Idiopathic Normal Pressure Hydrocephalus-The Idiopathic Normal Pressure Hydrocephalus Comorbidity and Risk Factors Associated With Hydrocephalus Study. Neurosurgery 2021; 89:122-128. [PMID: 33830219 DOI: 10.1093/neuros/nyab094] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 01/24/2021] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Gait and balance impairment are typical symptoms of idiopathic normal pressure hydrocephalus (INPH), implicating that falls may afflict these patients. OBJECTIVE To investigate falls, related injuries, and associated psychological features, before and after shunt surgery for INPH and compared to the general population. METHODS The study included 176 patients shunted for INPH and 368 age- and sex-matched controls. Falls, fear of falling (FOF), fall-related injuries (mild-severe), confidence in avoiding falls (Swedish Falls Efficacy Scale (FES(S)), quality of life (QoL; EuroQoL 5-dimension 5 level instrument), and symptoms of depression (Geriatric Depression Scale 15) were investigated. Pre- and postoperative observational times were 12 mo before surgery and 21 mo after (mean). Recurrent fallers fell ≥2 times. RESULTS More INPH patients than controls were recurrent fallers (67% vs 11%; P < .001). They feared falling more often (FOF, mean ± standard deviation: 3.3 ± 1.1 vs 1.6 ± 0.9; P < .001) and had lower confidence in avoiding falls (FES(S) 78 ± 40 vs 126 ± 14; P < .001). After surgery, INPH patients improved in all parameters but they did not reach the levels of the controls. Among fallers there was no difference between patients and controls in the severity of injuries suffered. Low QoL and symptoms of depression were more common among recurrent fallers than one-time or nonfallers in both shunted patients and controls (P ≤ .001). CONCLUSION Falls, FOF, and low confidence in avoiding falls are considerable problems in INPH that may be reduced by shunt surgery. We suggest that remaining risk of falling and preventative measures are routinely considered in postoperative follow-ups and rehabilitation planning.
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Affiliation(s)
- Jenny Larsson
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Hanna Israelsson
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden.,Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Lillemor Lundin-Olsson
- Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
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26
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Zarrinkoob L, Wåhlin A, Ambarki K, Eklund A, Malm J. Quantification and mapping of cerebral hemodynamics before and after carotid endarterectomy, using four-dimensional flow magnetic resonance imaging. J Vasc Surg 2021; 74:910-920.e1. [PMID: 33812036 DOI: 10.1016/j.jvs.2021.01.074] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 01/26/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND Carotid stenosis can profoundly affect cerebral hemodynamics, which cannot simply be inferred from the degree of stenosis. We quantified and mapped the distribution of the blood flow rate (BFR) in the cerebral arteries before and after carotid endarterectomy using four-dimensional (4D) phase-contrast (PC) magnetic resonance imaging (MRI). METHODS Nineteen patients (age, 71 ± 6 years; 2 women) with symptomatic carotid stenosis (≥50%) undergoing carotid endarterectomy (CEA) were investigated using 4D PC-MRI before and after surgery. The BFR was measured in 17 cerebral arteries and the ophthalmic arteries. Collateral recruitment through the anterior and posterior communicating arteries, ophthalmic arteries, and leptomeningeal arteries was quantified. BFR laterality was significantly different between the paired contralateral and ipsilateral arteries. Subgroups were defined according to the presence of collateral recruitment. RESULTS The total cerebral blood flow had increased by 15% (P < .01) after CEA. Before CEA, laterality was seen in the internal carotid artery, anterior cerebral artery, and middle cerebral artery (MCA). On the ipsilateral side, an increased BFR was found after CEA in the internal carotid artery (246 ± 62 mL/min vs 135 ± 80 mL/min; P < .001), anterior cerebral artery (87 ± mL/min vs 38 ± 58 mL/min; P < .01), and MCA (149 ± 43 mL/min vs 119 ± 34 mL/min; P < .01), resulting in a postoperative BFR distribution without signs of laterality. In the nine patients with preoperatively recruited collaterals, BFR laterality was found in the MCA before, but not after, CEA (P < .01). This laterality was not found in the 10 patients without collateral recruitment (P = .2). The degree of stenosis did not differ between the groups with and without collateral recruitment (P = .85). CONCLUSIONS Using 4D PC-MRI, we have presented a comprehensive and noninvasive method to evaluate the cerebral hemodynamics due to carotid stenosis before and after CEA. MCA laterality, seen in the patients with collateral recruitment before CEA, pointed toward a hemodynamic disturbance in MCA territory for those patients. This methodologic advancement provides an insight into the pathophysiology of cerebral hemodynamics in patients with carotid stenosis.
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Affiliation(s)
- Laleh Zarrinkoob
- Division of Neuroscience, Department of Clinical Sciences, Umeå University, Umeå, Sweden; Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden.
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden; Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden; Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Khalid Ambarki
- Department of Radiation Sciences, Umeå University, Umeå, Sweden; Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden; Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
| | - Jan Malm
- Division of Neuroscience, Department of Clinical Sciences, Umeå University, Umeå, Sweden
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27
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Wåhlin A, Holmlund P, Fellows AM, Malm J, Buckey JC, Eklund A. Reply. Ophthalmology 2021; 128:e28. [PMID: 33551287 DOI: 10.1016/j.ophtha.2021.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 12/30/2020] [Accepted: 01/05/2021] [Indexed: 11/29/2022] Open
Affiliation(s)
- Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden; Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Petter Holmlund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | | | - Jan Malm
- Department of Clinical Science, Umeå University, Umeå, Sweden
| | - Jay C Buckey
- Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden; Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden.
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28
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Holmgren M, Støverud KH, Zarrinkoob L, Wåhlin A, Malm J, Eklund A. Middle cerebral artery pressure laterality in patients with symptomatic ICA stenosis. PLoS One 2021; 16:e0245337. [PMID: 33417614 PMCID: PMC7793245 DOI: 10.1371/journal.pone.0245337] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/28/2020] [Indexed: 11/18/2022] Open
Abstract
An internal carotid artery (ICA) stenosis can potentially decrease the perfusion pressure to the brain. In this study, computational fluid dynamics (CFD) was used to study if there was a hemispheric pressure laterality between the contra- and ipsilateral middle cerebral artery (MCA) in patients with a symptomatic ICA stenosis. We further investigated if this MCA pressure laterality (ΔPMCA) was related to the hemispheric flow laterality (ΔQ) in the anterior circulation, i.e., ICA, proximal MCA and the proximal anterior cerebral artery (ACA). Twenty-eight patients (73±6 years, range 59–80 years, 21 men) with symptomatic ICA stenosis were included. Flow rates were measured using 4D flow MRI data (PC-VIPR) and vessel geometries were obtained from computed tomography angiography. The ΔPMCA was calculated from CFD, where patient-specific flow rates were applied at all input- and output boundaries. The ΔPMCA between the contra- and ipsilateral side was 6.4±8.3 mmHg (p<0.001) (median 3.9 mmHg, range -1.3 to 31.9 mmHg). There was a linear correlation between the ΔPMCA and ΔQICA (r = 0.85, p<0.001) and ΔQACA (r = 0.71, p<0.001), respectively. The correlation to ΔQMCA was weaker (r = 0.47, p = 0.011). In conclusion, the MCA pressure laterality obtained with CFD, is a promising physiological biomarker that can grade the hemodynamic disturbance in patients with a symptomatic ICA stenosis.
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Affiliation(s)
| | | | - Laleh Zarrinkoob
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden.,Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
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29
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Abstract
Recent reports have suggested that age-related arterial stiffening and excessive cerebral arterial pulsatility cause blood-brain barrier breakdown, brain atrophy and cognitive decline. This has spurred interest in developing non-invasive methods to measure pulsatility in distal vessels, closer to the cerebral microcirculation. Here, we report a method based on four-dimensional (4D) flow MRI to estimate a global composite flow waveform of distal cerebral arteries. The method is based on finding and sampling arterial waveforms from thousands of cross sections in numerous small vessels of the brain, originating from cerebral cortical arteries. We demonstrate agreement with internal and external reference methods and show the ability to capture significant increases in distal cerebral arterial pulsatility as a function of age. The proposed approach can be used to advance our understanding regarding excessive arterial pulsatility as a potential trigger of cognitive decline and dementia.
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Affiliation(s)
- Tomas Vikner
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Tomas Vikner, Department of Radiation Sciences, Umeå University, Umeå SE 901 87, Sweden.
| | - Lars Nyberg
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
- Department of Integrative Medical Biology (IMB), Umeå University, Umeå, Sweden
| | | | - 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 (UFBI), Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
- Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden
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Israelsson H, Eklund A, Malm J. Cerebrospinal Fluid Shunting Improves Long-Term Quality of Life in Idiopathic Normal Pressure Hydrocephalus. Neurosurgery 2020; 86:574-582. [PMID: 31504827 DOI: 10.1093/neuros/nyz297] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 04/04/2019] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The short- and long-term impact of cerebrospinal fluid shunting on quality of life (QoL) in idiopathic normal pressure hydrocephalus (INPH) is poorly understood. OBJECTIVE To investigate QoL in shunted INPH patients compared to the population and to investigate which factors influence QoL in INPH. METHODS INPH patients consecutively shunted in Sweden during 2008-2010 were scrutinized. Population-based controls were age- and sex-matched to the patients. Included participants were the following: 176 INPH patients and 368 controls. QoL was assessed using the EuroQol 5-dimension 5-level (EQ5D5L) instrument, which measures overall QoL and health status in 5 dimensions. Independency (accommodation and/or need for in-home care) and comorbidities were assessed. Patients were followed up 6-45 mo after surgery (mean follow-up time: 21 mo). RESULTS Shunting improved QoL (P < .001) and health status in all dimensions (P < .005). Shunted INPH patients had lower QoL than controls (P < .001). The patients' health status in mobility, self-care, daily activities, and anxiety/depression was worse than the controls both before and after surgery (P < .001). The main predictors of low QoL in INPH were symptoms of depression (P < .001) and severity of gait disturbance (P = .001). Fewer INPH patients than controls lived independently (45% vs 85%, P < .001). Time after shunting had no influence on QoL. CONCLUSION QoL remains improved in shunted INPH patients at a mean follow-up time of 21 mo, but the patients do not reach the same QoL as the population. Symptoms of depression and severity of gait disturbance are the strongest predictors of low QoL in INPH.
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Affiliation(s)
- Hanna Israelsson
- Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Center for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden
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Israelsson H, Larsson J, Eklund A, Malm J. Risk factors, comorbidities, quality of life, and complications after surgery in idiopathic normal pressure hydrocephalus: review of the INPH-CRasH study. Neurosurg Focus 2020; 49:E8. [DOI: 10.3171/2020.7.focus20466] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 07/27/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVEIdiopathic normal pressure hydrocephalus (INPH) is a dementia treatable by insertion of a shunt that drains CSF. The cause of the disease is unknown, but a vascular pathway has been suggested. The INPH-CRasH (Comorbidities and Risk Factors Associated with Hydrocephalus) study was a modern epidemiological case-control study designed to prospectively assess parameters regarding comorbidities and vascular risk factors (VRFs) for INPH, quality of life (QOL), and adverse events in patients with shunted INPH. The objective of this review was to summarize the findings of the INPH-CRasH study.METHODSVRFs, comorbidities, QOL, and adverse events were analyzed in consecutive patients with INPH who underwent shunt placement between 2008 and 2010 in 5 of 6 neurosurgical centers in Sweden. Patients (n = 176, within the age span of 60–85 years and not having dementia) were compared to population-based age- and gender-matched controls (n = 368, same inclusion criteria as for the patients with INPH). Assessed parameters were as follows: hypertension; diabetes; obesity; hyperlipidemia; psychosocial factors (stress and depression); smoking status; alcohol intake; physical activity; dietary pattern; cerebrovascular, cardiovascular, or peripheral vascular disease; epilepsy; abdominal pain; headache; and clinical parameters before and after surgery. Parameters were assessed through questionnaires, clinical examinations, measurements, ECG studies, and blood samples.RESULTSFour VRFs were independently associated with INPH: hyperlipidemia, diabetes, obesity, and psychosocial factors. Physical inactivity and hypertension were also associated with INPH, although not independently from the other risk factors. The population attributable risk percent for a model containing all of the VRFs associated with INPH was 24%. Depression was overrepresented in patients with INPH treated with shunts compared to the controls (46% vs 13%, p < 0.001) and the main predictor for low QOL was a coexisting depression (p < 0.001). Shunting improved QOL on a long-term basis. Epilepsy, headache, and abdominal pain remained common for a mean follow-up time of 21 months in INPH patients who received shunts.CONCLUSIONSThe results of the INPH-CRasH study are consistent with a vascular pathophysiological component of INPH. In clinical care and research, a complete risk factor analysis as well as screening for depression and a measurement for QOL should probably be included in the workup of patients with INPH. The effect of targeted interventions against modifiable VRFs and antidepressant treatment in INPH patients should be evaluated. Seizures, headache, and abdominal pain should be inquired about at postoperative follow-up examinations.
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Affiliation(s)
- Hanna Israelsson
- 1Department of Clinical Science, Neurosciences, Umeå University, Umeå
- 2Department of Health, Medicine and Caring Sciences (HMV), Linköping University Hospital, Linköping; and
| | - Jenny Larsson
- 1Department of Clinical Science, Neurosciences, Umeå University, Umeå
| | - Anders Eklund
- 3Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Jan Malm
- 1Department of Clinical Science, Neurosciences, Umeå University, Umeå
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Wåhlin A, Holmlund P, Fellows AM, Malm J, Buckey JC, Eklund A. Optic Nerve Length before and after Spaceflight. Ophthalmology 2020; 128:309-316. [PMID: 32659310 DOI: 10.1016/j.ophtha.2020.07.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/02/2020] [Accepted: 07/06/2020] [Indexed: 10/23/2022] Open
Abstract
PURPOSE The spaceflight-associated neuro-ocular syndrome (SANS) affects astronauts on missions to the International Space Station (ISS). The SANS has blurred vision and ocular changes as typical features. The objective of this study was to investigate if microgravity can create deformations or movements of the eye or optic nerve, and if such changes could be linked to SANS. DESIGN Cohort study. PARTICIPANTS Twenty-two astronauts (age 48 ± 4 years). METHODS The intervention consisted of time in microgravity at the ISS. We co-registered pre- and postspaceflight magnetic resonance imaging (MRI) scans and generated centerline representations of the optic nerve. The coordinates for the optic nerve head (ONH) and optic chiasm (OC) ends of the optic nerve were recorded along with the entire centerline path. MAIN OUTCOME MEASURES Optic nerve length, ONH movement, and OC movement after time in microgravity. RESULTS Optic nerve length increased (0.80 ± 0.74 mm, P < 0.001), primarily reflecting forward ONH displacement (0.63 ± 0.53 mm, P < 0.001). The forward displacement was positively related to mission duration, preflight body weight, and clinical manifestations of SANS. We also detected upward displacement of the OC (0.39 ± 0.50 mm, P = 0.002), indicative of brain movement, but this observation could not be linked to SANS. CONCLUSIONS The spaceflight-induced optic nerve lengthening and anterior movement of the ONH support that SANS is caused by an altered pressure difference between the brain and the eye, leading to a forward push on the posterior of the eye. Body weight is a potential contributing risk factor. Direct assessment of intracranial pressure in space is required to verify the implicated mechanism behind the ocular findings in SANS.
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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
| | - Petter Holmlund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | | | - Jan Malm
- Department of Clinical Science, Umeå University, Umeå, Sweden
| | - Jay C Buckey
- Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden; Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden.
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Gasslander J, Sundström N, Eklund A, Koskinen LOD, Malm J. Risk factors for developing subdural hematoma: a registry-based study in 1457 patients with shunted idiopathic normal pressure hydrocephalus. J Neurosurg 2020:1-10. [PMID: 31923893 DOI: 10.3171/2019.10.jns191223] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 10/29/2019] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Subdural hematomas and hygromas (SDHs) are common complications in idiopathic normal pressure hydrocephalus (iNPH) patients with shunts. In this registry-based study, patients with shunted iNPH were screened nationwide to identify perioperative variables that may increase the risk of SDH. METHODS The Swedish Hydrocephalus Quality Registry was reviewed for iNPH patients who had undergone shunt surgery in Sweden in 2004-2014. Potential risk factors for SDH were recorded preoperatively and 3 months after surgery. Drug prescriptions were identified from a national pharmacy database. Patients who developed SDHs were compared with those without SDHs. RESULTS The study population consisted of 1457 patients, 152 (10.4%) of whom developed an SDH. Men developed an SDH more often than women (OR 2.084, 95% CI 1.421-3.058, p < 0.001). Patients on platelet aggregation inhibitors developed an SDH more often than those who were not (OR 1.733, 95% CI 1.236-2.431, p = 0.001). At surgery, shunt opening pressures had been set 5.9 mm H2O lower in the SDH group than in the no-SDH group (109.6 ± 24.1 vs 115.5 ± 25.4 mm H2O, respectively, p = 0.009). Antisiphoning devices (ASDs) were used in 892 patients but did not prevent SDH. Mean opening pressures at surgery and the follow-up were lower with shunts with an ASD, without causing more SDHs. No other differences were seen between the groups. CONCLUSIONS iNPH patients in this study were diagnosed and operated on in routine practice; thus, the results represent everyday care. Male sex, antiplatelet medication, and a lower opening pressure at surgery were risk factors for SDH. Physical status and comorbidity were not. ASD did not prevent SDH, but a shunt with an ASD allowed a lower opening pressure without causing more SDHs.
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Affiliation(s)
- Johan Gasslander
- 1Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå
- 2Departments of Cardiology and Health, Medicine and Caring Services, Linkoping University, Vrinnevi General Hospital Norrköping; and
| | - Nina Sundström
- 3Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Anders Eklund
- 3Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Lars-Owe D Koskinen
- 1Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå
| | - Jan Malm
- 1Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå
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Zarrinkoob L, Wåhlin A, Ambarki K, Birgander R, Eklund A, Malm J. Blood Flow Lateralization and Collateral Compensatory Mechanisms in Patients With Carotid Artery Stenosis. Stroke 2020; 50:1081-1088. [PMID: 30943887 PMCID: PMC6485302 DOI: 10.1161/strokeaha.119.024757] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Background and Purpose- Four-dimensional phase-contrast magnetic resonance imaging enables quantification of blood flow rate (BFR; mL/min) in multiple cerebral arteries simultaneously, making it a promising technique for hemodynamic investigation in patients with stroke. The aim of this study was to quantify the hemodynamic disturbance and the compensatory pattern of collateral flow in patients with symptomatic carotid stenosis. Methods- Thirty-eight patients (mean, 72 years; 27 men) with symptomatic carotid stenosis (≥50%) or occlusion were investigated using 4-dimensional phase-contrast magnetic resonance imaging. For each patient, BFR was measured in 19 arteries/locations. The ipsilateral side to the symptomatic carotid stenosis was compared with the contralateral side. Results- Internal carotid artery BFR was lower on the ipsilateral side (134±87 versus 261±95 mL/min; P<0.001). BFR in anterior cerebral artery (A1 segment) was lower on ipsilateral side (35±58 versus 119±72 mL/min; P<0.001). Anterior cerebral artery territory bilaterally was primarily supplied by contralateral internal carotid artery. The ipsilateral internal carotid artery mainly supplied the ipsilateral middle cerebral artery (MCA) territory. MCA was also supplied by a reversed BFR found in the ophthalmic and the posterior communicating artery routes on the ipsilateral side (-5±28 versus 10±28 mL/min, P=0.001, and -2±12 versus 6±6 mL/min, P=0.03, respectively). Despite these compensations, BFR in MCA was lower on the ipsilateral side, and this laterality was more pronounced in patients with severe carotid stenosis (≥70%). Although comparing ipsilateral MCA BFR between stenosis groups (<70% and ≥70%), there was no difference ( P=0.95). Conclusions- With a novel approach using 4-dimensional phase-contrast magnetic resonance imaging, we could simultaneously quantify and rank the importance of collateral routes in patients with carotid stenosis. An important observation was that contralateral internal carotid artery mainly secured the bilateral anterior cerebral artery territory. Because of the collateral recruitment, compromised BFR in MCA is not necessarily related to the degree of carotid stenosis. These findings highlight the importance of simultaneous investigation of the hemodynamics of the entire cerebral arterial tree.
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Affiliation(s)
- Laleh Zarrinkoob
- From the Department of Pharmacology and Clinical Neuroscience, Umeå, Sweden (L.Z., J.M.).,Department of Surgical and Perioperative Sciences, Umeå, Sweden (L.Z.)
| | - Anders Wåhlin
- Department of Radiation Science, Umeå, Sweden (A.W., K.A., R.B., A.E.).,Centre for Biomedical Engineering and Physics, Umeå, Sweden (A.W., K.A., A.E.).,Umeå Center for Functional Brain Imaging, Sweden (A.W., A.E.)
| | - Khalid Ambarki
- Department of Radiation Science, Umeå, Sweden (A.W., K.A., R.B., A.E.).,Centre for Biomedical Engineering and Physics, Umeå, Sweden (A.W., K.A., A.E.)
| | - Richard Birgander
- Department of Radiation Science, Umeå, Sweden (A.W., K.A., R.B., A.E.)
| | - Anders Eklund
- Department of Radiation Science, Umeå, Sweden (A.W., K.A., R.B., A.E.).,Centre for Biomedical Engineering and Physics, Umeå, Sweden (A.W., K.A., A.E.).,Umeå Center for Functional Brain Imaging, Sweden (A.W., A.E.)
| | - Jan Malm
- From the Department of Pharmacology and Clinical Neuroscience, Umeå, Sweden (L.Z., J.M.)
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Ryska P, Slezak O, Eklund A, Malm J, Salzer J, Zizka J. Radiological markers of idiopathic normal pressure hydrocephalus: Relative comparison of their diagnostic performance. J Neurol Sci 2020; 408:116581. [DOI: 10.1016/j.jns.2019.116581] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 10/17/2019] [Accepted: 11/15/2019] [Indexed: 02/01/2023]
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Holmlund P, Qvarlander S, Malm J, Eklund A. Can pulsatile CSF flow across the cerebral aqueduct cause ventriculomegaly? A prospective study of patients with communicating hydrocephalus. Fluids Barriers CNS 2019; 16:40. [PMID: 31865917 PMCID: PMC6927212 DOI: 10.1186/s12987-019-0159-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 12/05/2019] [Indexed: 11/26/2022] Open
Abstract
Background Communicating hydrocephalus is a disease where the cerebral ventricles are enlarged. It is characterized by the absence of detectable cerebrospinal fluid (CSF) outflow obstructions and often with increased CSF pulsatility measured in the cerebral aqueduct (CA). We hypothesize that the cardiac-related pulsatile flow over the CA, with fast systolic outflow and slow diastolic inflow, can generate net pressure effects that could source the ventriculomegaly in these patients. This would require a non-zero cardiac cycle averaged net pressure difference (ΔPnet) over the CA, with higher average pressure in the lateral and third ventricles. Methods We tested the hypothesis by calculating ΔPnet across the CA using computational fluid dynamics based on prospectively collected high-resolution structural (FIESTA-C, resolution 0.39 × 0.39 × 0.3 mm3) and velocimetric (2D-PCMRI, in-plane resolution 0.35 × 0.35 mm2) MRI-data from 30 patients investigated for communicating hydrocephalus. Results The ΔPnet due to CSF pulsations was non-zero for the study group (p = 0.03) with a magnitude of 0.2 ± 0.4 Pa (0.001 ± 0.003 mmHg), with higher pressure in the third ventricle. The maximum pressure difference over the cardiac cycle ΔPmax was 20.3 ± 11.8 Pa and occurred during systole. A generalized linear model verified an association between ΔPnet and CA cross-sectional area (p = 0.01) and flow asymmetry, described by the ratio of maximum inflow/outflow (p = 0.04), but not for aqueductal stroke volume (p = 0.35). Conclusions The results supported the hypothesis with respect to the direction of ΔPnet, although the magnitude was low. Thus, although the pulsations may generate a pressure difference across the CA it is likely too small to explain the ventriculomegaly in communicating hydrocephalus.
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Affiliation(s)
- P Holmlund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.
| | - S Qvarlander
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - J Malm
- Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden
| | - A Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Centre for Functional Brain Imaging, Umeå University, Umeå, Sweden
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Birnefeld J, Wåhlin A, Eklund A, Malm J. Cerebral arterial pulsatility is associated with features of small vessel disease in patients with acute stroke and TIA: a 4D flow MRI study. J Neurol 2019; 267:721-730. [PMID: 31728712 PMCID: PMC7035303 DOI: 10.1007/s00415-019-09620-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 10/30/2019] [Accepted: 11/02/2019] [Indexed: 11/16/2022]
Abstract
Cerebral small vessel disease (SVD) is a major cause of stroke and cognitive impairment. However, the underlying mechanisms behind SVD are still poorly understood. High cerebral arterial pulsatility has been suggested as a possible cause of SVD. In population studies, arterial pulsatility has been linked to white matter hyperintensities (WMH), cerebral atrophy, and cognitive impairment, all features of SVD. In stroke, pulsatility data are scarce and contradictory. The aim of this study was to investigate the relationship between arterial pulsatility and SVD in stroke patients. With a cross-sectional design, 89 patients with acute ischemic stroke or TIA were examined with MRI. A neuropsychological assessment was performed 1 year later. Using 4D flow MRI, pulsatile indices (PI) were calculated for the internal carotid artery (ICA) and middle cerebral artery (M1, M3). Flow volume pulsatility (FVP), a measure corresponding to the cyclic expansion of the arterial tree, was calculated for the same locations. These parameters were assessed for associations with WMH volume, brain volume and cognitive function. ICA-FVP was associated with WMH volume (β = 1.67, 95% CI: [0.1, 3.24], p = 0.037). M1-PI and M1-FVP were associated with decreasing cognitive function (β = − 4.4, 95% CI: [− 7.7, − 1.1], p = 0.009 and β = − 13.15, 95% CI: [− 24.26, − 2.04], p = 0.02 respectively). In summary, this supports an association between arterial pulsatility and SVD in stroke patients, and provides a potential target for further research and preventative treatment. FVP may become a useful biomarker for assessing pulsatile stress with PCMRI and 4D flow MRI.
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Affiliation(s)
- Johan Birnefeld
- Department of Pharmacology and Clinical Neuroscience, Umeå University, 90187, Umeå, Sweden.
| | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Centre for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Pharmacology and Clinical Neuroscience, Umeå University, 90187, Umeå, Sweden
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- Michael A. Williams
- Adult & Transitional Hydrocephalus, Departments of Neurology and Neurological Surgery, University of Washington School of Medicine, Seattle
| | - Jan Malm
- Umeå Hydrocephalus Research Group, Department of Clinical Neuroscience, University of Umeå, Umeå, Sweden
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Westlund A, Holmlund P, Johansson E, Malm J, Eklund A. Semi-automatic method for segmentation of the internal jugular vein in ultrasound movies evaluated at different body postures. Biomed Phys Eng Express 2019. [DOI: 10.1088/2057-1976/ab285e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Abstract
Objective: The collapse of the internal jugular vein (IJV) regulates intracranial pressure (ICP) in upright body positions. The cross-section area (CSA) is therefore of interest when studying the effects of postural changes in various neurological diseases. We have developed a semi-automatic segmentation method, which tracks the CSA of the IJV in ultrasound movies, and evaluated its performance in three body positions (supine, 16°, 71°). Approach: The proposed method utilized post-processing image filtering combined with a modified snake active contour algorithm. The ultrasound movies were retrospectively analysed (n = 231, 3s, 28 fps) based on previously collected data from 17 healthy volunteers. The computed CSAs (CA) from the segmentation method were compared to manually segmented CSAs (MA) in two frames per movie. Tracking performance were evaluated by visual inspection. Main results: In the supine position, 100% of the ultrasound movies were tracked successfully, and the mean of CA-MA was −4.4 ± 6.9 mm2 (MA, 88.4 ± 50.5 mm2). The most challenging movies occurred in upright body posture where tracking success rate was 90% and mean of CA-MA was −1.4 ± 2.2 mm2 (MA, 12.0 ± 11.1 mm2). The semi-automatic segmentations took 55 s to perform on average (per movie) compared to manual segmentations which took 50 min. Significance: Segmentations made by the proposed method were comparable to manual segmentations in all tilt-angles, however much faster. Efficient and accurate tracking of the CSA of the IJV, with respect to postural changes, could help furthering our understanding of how IJV-biomechanics relates to regulation of intracranial pressure in different neurological diseases and physiological states.
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Roider T, Frauhammer F, Seufert J, Bordas M, Stolarczyk M, Rabe S, Malm J, Bruch P, Hundemer M, Rippe K, Goeppert B, Seiffert M, Brors B, Mechtersheimer G, Müller-Tidow C, Fröhling S, Schlesner M, Huber W, Anders S, Dietrich S. TRANSCRIPTIONAL AND GENOMIC INTRA-TUMOR HETEROGENEITY DRIVES SUBCLONE SPECIFIC DRUG RESPONSES IN DIFFUSE LARGE B CELL LYMPHOMA. Hematol Oncol 2019. [DOI: 10.1002/hon.45_2629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- T. Roider
- Department of Medicine V; Hematology, Oncology and Rheumatology, University of Heidelberg; Heidelberg Germany
| | - F. Frauhammer
- Centre for Molecular Biology; University of Heidelberg; Heidelberg Germany
| | - J. Seufert
- Bioinformatics and Omics Data Analytics; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - M. Bordas
- Department of Molecular Genetics; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - M. Stolarczyk
- Department of Medicine V; Hematology, Oncology and Rheumatology, University of Heidelberg; Heidelberg Germany
| | - S. Rabe
- Department of Medicine V; Hematology, Oncology and Rheumatology, University of Heidelberg; Heidelberg Germany
| | - J. Malm
- Division of Chromatin Networks; German Cancer Research Center (DKFZ) and Bioquant; Heidelberg Germany
| | - P. Bruch
- Department of Medicine V; Hematology, Oncology and Rheumatology, University of Heidelberg; Heidelberg Germany
| | - M. Hundemer
- Department of Medicine V; Hematology, Oncology and Rheumatology, University of Heidelberg; Heidelberg Germany
| | - K. Rippe
- Division of Chromatin Networks; German Cancer Research Center (DKFZ) and Bioquant; Heidelberg Germany
| | - B. Goeppert
- Institute of Pathology; University of Heidelberg; Heidelberg Germany
| | - M. Seiffert
- Department of Molecular Genetics; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - B. Brors
- Bioinformatics and Omics Data Analytics; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - G. Mechtersheimer
- Institute of Pathology; University of Heidelberg; Heidelberg Germany
| | - C. Müller-Tidow
- Department of Medicine V; Hematology, Oncology and Rheumatology, University of Heidelberg; Heidelberg Germany
| | - S. Fröhling
- Translational Oncology; National Center for Tumor Diseases (NCT); Heidelberg Germany
| | - M. Schlesner
- Bioinformatics and Omics Data Analytics; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - W. Huber
- Genome Biology; European Molecular Biology Laboratory (EMBL); Heidelberg Germany
| | - S. Anders
- Centre for Molecular Biology; University of Heidelberg; Heidelberg Germany
| | - S. Dietrich
- Department of Medicine V; Hematology, Oncology and Rheumatology, University of Heidelberg; Heidelberg Germany
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Wåhlin A, Fordell H, Ekman U, Lenfeldt N, Malm J. Rehabilitation in chronic spatial neglect strengthens resting-state connectivity. Acta Neurol Scand 2019; 139:254-259. [PMID: 30427058 DOI: 10.1111/ane.13048] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 11/07/2018] [Accepted: 11/09/2018] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Rehabilitation of patients with chronic visuospatial neglect is underexplored, and little is known about neural mechanisms that can be exploited to promote recovery. In this study, we present data on resting-state functional connectivity within the dorsal attention network (DAN) in chronic neglect patients as they underwent training in a virtual reality (VR) environment that improved left-side awareness. METHODS The study included 13 patients with visuospatial neglect persisting more than six months after a right-sided stroke. The patients underwent resting-state functional magnetic resonance imaging (fMRI). Scans were collected at baseline and after five weeks of intense training. We specifically examined resting-state functional connectivity within the DAN. In addition, using spatial concordance correlation, we compared changes in the spatial topology of the DAN with that of other networks. RESULTS We found a longitudinal increase in interhemispheric functional connectivity between the right frontal eye field and the left intraparietal sulcus following training (before: 0.33 ± 0.17 [mean ± SD]; after: 0.45 ± 0.13; P = 0.004). The spatial concordance analyses indicated that training influenced the DAN connectivity more than any of the other networks. CONCLUSION Intense VR training that improved left-sided awareness in chronic stroke patients also increased sporadic interhemispheric functional connectivity within the DAN. Specifically, a region responsible for saccadic eye movement to the left became more integrated with the left posterior parietal cortex. These results highlight a mechanism that should be exploited in the training of patients with chronic visuospatial neglect.
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Affiliation(s)
- Anders Wåhlin
- Department of Radiation Sciences, Biomedical Engineering; Umeå University; Umeå Sweden
- Umeå Center for Functional Brain Imaging; Umeå University; Umeå Sweden
| | - Helena Fordell
- Department of Pharmacology and Clinical Neuroscience; Umeå University; Umeå Sweden
| | - Urban Ekman
- Umeå Center for Functional Brain Imaging; Umeå University; Umeå Sweden
- Department of Integrative Medical Biology; Umeå University; Umeå Sweden
- Department of Neurobiology, Care Sciences and Society; Karolinska Institutet; Stockholm Sweden
| | - Niklas Lenfeldt
- Department of Pharmacology and Clinical Neuroscience; Umeå University; Umeå Sweden
| | - Jan Malm
- Department of Pharmacology and Clinical Neuroscience; Umeå University; Umeå Sweden
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Behrens A, Elgh E, Leijon G, Kristensen B, Eklund A, Malm J. The Computerized General Neuropsychological INPH Test revealed improvement in idiopathic normal pressure hydrocephalus after shunt surgery. J Neurosurg 2019; 132:733-740. [PMID: 30738407 DOI: 10.3171/2018.10.jns18701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 10/02/2018] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The Computerized General Neuropsychological INPH Test (CoGNIT) provides the clinician and the researcher with standardized and accessible cognitive assessments in patients with idiopathic normal pressure hydrocephalus (INPH). CoGNIT includes tests of memory, executive functions, attention, manual dexterity, and psychomotor speed. Investigations of the validity and reliability of CoGNIT have been published previously. The aim of this study was to evaluate CoGNIT's sensitivity to cognitive change after shunt surgery in patients with INPH. METHODS Forty-one patients with INPH (median Mini-Mental State Examination score 26) were given CoGNIT preoperatively and at a postoperative follow-up 4 months after shunt surgery. Scores were compared to those of 44 healthy elderly control volunteers. CoGNIT was administered by either a nurse or an occupational therapist. RESULTS Improvement after shunt surgery was seen in all cognitive domains: memory (10-word list test, p < 0.01); executive functions (Stroop incongruent color and word test, p < 0.01); attention (2-choice reaction test, p < 0.01); psychomotor speed (Stroop congruent color and word test, p < 0.01); and manual dexterity (4-finger tapping, p < 0.01). No improvement was seen in the Mini-Mental State Examination score. Preoperative INPH test scores were significantly impaired compared to healthy control subjects (p < 0.001 for all tests). CONCLUSIONS In this study the feasibility for CoGNIT to detect a preoperative impairment and postoperative improvement in INPH was demonstrated. CoGNIT has the potential to become a valuable tool in clinical and research work.Clinical trial registration no.: NCT01618500 (clinicaltrials.gov).
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Affiliation(s)
- Anders Behrens
- 1Department of Medicine, Blekinge Hospital, Karlskrona.,2Department of Pharmacology and Clinical Neuroscience
| | | | - Göran Leijon
- 4Department of Clinical and Experimental Medicine, Faculty of Health Science, Linköping University Hospital, Linköping, Sweden; and
| | - Bo Kristensen
- 5Department of Neurology, Aalborg University Hospital, Aalborg, Denmark
| | - Anders Eklund
- 6Centre for Biomedical Engineering and Physics, and.,7Department of Radiation Science, Umeå University, Umeå
| | - Jan Malm
- 2Department of Pharmacology and Clinical Neuroscience
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Dunås T, Holmgren M, Wåhlin A, Malm J, Eklund A. Accuracy of blood flow assessment in cerebral arteries with 4D flow MRI: Evaluation with three segmentation methods. J Magn Reson Imaging 2019; 50:511-518. [PMID: 30637846 PMCID: PMC6767555 DOI: 10.1002/jmri.26641] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 12/20/2018] [Accepted: 12/20/2018] [Indexed: 12/03/2022] Open
Abstract
Background Accelerated 4D flow MRI allows for high‐resolution velocity measurements with whole‐brain coverage. Such scans are increasingly used to calculate flow rates of individual arteries in the vascular tree, but detailed information about the accuracy and precision in relation to different postprocessing options is lacking. Purpose To evaluate and optimize three proposed segmentation methods and determine the accuracy of in vivo 4D flow MRI blood flow rate assessments in major cerebral arteries, with high‐resolution 2D PCMRI as a reference. Study Type Prospective. Subjects Thirty‐five subjects (20 women, 79 ± 5 years, range 70–91 years). Field Strength/Sequence 4D flow MRI with PC‐VIPR and 2D PCMRI acquired with a 3 T scanner. Assessment We compared blood flow rates measured with 4D flow MRI, to the reference, in nine main cerebral arteries. Lumen segmentation in the 4D flow MRI was performed with k‐means clustering using four different input datasets, and with two types of thresholding methods. The threshold was defined as a percentage of the maximum intensity value in the complex difference image. Local and global thresholding approaches were used, with evaluated thresholds from 6–26%. Statistical Tests Paired t‐test, F‐test, linear correlation (P < 0.05 was considered significant) along with intraclass correlation (ICC). Results With the thresholding methods, the lowest average flow difference was obtained for 20% local (0.02 ± 15.0 ml/min, ICC = 0.97, n = 310) or 10% global (0.08 ± 17.3 ml/min, ICC = 0.97, n = 310) thresholding with a significant lower standard deviation for local (F‐test, P = 0.01). For all clustering methods, we found a large systematic underestimation of flow compared with 2D PCMRI (16.1–22.3 ml/min). Data Conclusion A locally adapted threshold value gives a more stable result compared with a globally fixed threshold. 4D flow with the proposed segmentation method has the potential to become a useful reliable clinical tool for assessment of blood flow in the major cerebral arteries. Level of Evidence: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:511–518.
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Affiliation(s)
- Tora Dunås
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | | | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, 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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Dunås T, Wåhlin A, Zarrinkoob L, Malm J, Eklund A. 4D flow MRI—Automatic assessment of blood flow in cerebral arteries. Biomed Phys Eng Express 2018. [DOI: 10.1088/2057-1976/aae8d1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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46
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Jacobsson J, Qvarlander S, Eklund A, Malm J. Comparison of the CSF dynamics between patients with idiopathic normal pressure hydrocephalus and healthy volunteers. J Neurosurg 2018; 131:1-6. [PMID: 30497143 DOI: 10.3171/2018.5.jns173170] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 05/29/2018] [Indexed: 11/06/2022]
Abstract
OBJECTIVEIntracranial pressure (ICP), outflow resistance (Rout), and amplitude of cardiac-related ICP pulsations (AMPs) are established parameters to describe the CSF hydrodynamic system and are assumed, but not confirmed, to be disturbed in idiopathic normal pressure hydrocephalus (INPH). The aim of this study was to compare the CSF hydrodynamic profile between patients with INPH and healthy volunteers.METHODSSixty-two consecutive INPH patients (mean age 74 years) and 40 healthy volunteers (mean age 70 years) were included. Diagnosis was made by two independent neurologists who assessed patients' history, neurological status, and MRI studies. A CSF dynamic investigation through the lumbar route was performed: ICP and other CSF dynamic variables were blinded to the neurologists during the diagnostic process and were not used for establishing the diagnosis of INPH.RESULTSRout was significantly higher in INPH (Rout 17.1 vs 11.1; p < 0.001), though a substantial number of INPH subjects had normal Rout. There were no differences between INPH patients and controls regarding ICP (mean 11.5 mm Hg). At resting pressure, there was a trend that AMP in INPH was increased (2.4 vs 2.0 mm Hg; p = 0.109). The relationship between AMP and ICP was that they shared the same slope, but the curve was significantly shifted to the left for INPH (reduced P0 [p < 0.05]; i.e., higher AMP for the same ICP).CONCLUSIONSThis study established that the CSF dynamic profile of INPH deviates from that of healthy volunteers and that INPH should thus be regarded as a disease in which intracranial hydrodynamics are part of the pathophysiology.Clinical trial registration no.: NCT01188382 (clinicaltrials.gov).
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Affiliation(s)
| | - Sara Qvarlander
- 2Radiation Sciences-Biomedical Engineering, and
- 3Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
| | - Anders Eklund
- 2Radiation Sciences-Biomedical Engineering, and
- 3Centre for Biomedical Engineering and Physics, Umeå University, Umeå, Sweden
| | - Jan Malm
- Departments of1Pharmacology and Clinical Neuroscience and
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Ekman U, Fordell H, Eriksson J, Lenfeldt N, Wåhlin A, Eklund A, Malm J. Increase of frontal neuronal activity in chronic neglect after training in virtual reality. Acta Neurol Scand 2018; 138:284-292. [PMID: 29770439 DOI: 10.1111/ane.12955] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2018] [Indexed: 10/16/2022]
Abstract
OBJECTIVES A third of patients with stroke acquire spatial neglect associated with poor rehabilitation outcome. New effective rehabilitation interventions are needed. Scanning training combined with multisensory stimulation to enhance the rehabilitation effect is suggested. In accordance, we have designed a virtual-reality based scanning training that combines visual, audio and sensori-motor stimulation called RehAtt® . Effects were shown in behavioural tests and activity of daily living. Here, we use fMRI to evaluate the change in brain activity during Posner's Cuing Task (attention task) after RehAtt® intervention, in patients with chronic neglect. METHODS Twelve patients (mean age = 72.7 years, SD = 6.1) with chronic neglect (persistent symptoms >6 months) performed the interventions 3 times/wk during 5 weeks, in total 15 hours. Training effects on brain activity were evaluated using fMRI task-evoked responses during the Posner's cuing task before and after the intervention. RESULTS Patients improved their performance in the Posner fMRI task. In addition, patients increased their task-evoked brain activity after the VR interventions in an extended network including pre-frontal and temporal cortex during attentional cueing, but showed no training effects during target presentations. CONCLUSIONS The current pilot study demonstrates that a novel multisensory VR intervention has the potential to benefit patients with chronic neglect in respect of behaviour and brain changes. Specifically, the fMRI results show that strategic processes (top-down control during attentional cuing) were enhanced by the intervention. The findings increase knowledge of the plasticity processes underlying positive rehabilitation effects from RehAtt® in chronic neglect.
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Affiliation(s)
- U. Ekman
- Department of Integrative Medical Biology; Umeå University; Umeå Sweden
- Umeå Center for Functional Brain Imaging; Umeå University; Umeå Sweden
- Department of Neurobiology, Care Sciences and Society; Karolinska Institutet; Stockholm Sweden
| | - H. Fordell
- Department of Pharmacology and Clinical Neuroscience; Umeå University; Umeå Sweden
| | - J. Eriksson
- Department of Integrative Medical Biology; Umeå University; Umeå Sweden
- Umeå Center for Functional Brain Imaging; Umeå University; Umeå Sweden
| | - N. Lenfeldt
- Department of Pharmacology and Clinical Neuroscience; Umeå University; Umeå Sweden
| | - A. Wåhlin
- Department of Radiation Sciences; Biomedical Engineering; Umeå University; Umeå Sweden
| | - A. Eklund
- Umeå Center for Functional Brain Imaging; Umeå University; Umeå Sweden
- Department of Radiation Sciences; Biomedical Engineering; Umeå University; Umeå Sweden
| | - J. Malm
- Department of Pharmacology and Clinical Neuroscience; Umeå University; Umeå Sweden
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Sandvig A, Arnell K, Malm J, Eklund A, Koskinen LOD. Analysis of Codman microcerebrospinal fluid shunt. Brain Behav 2018; 8:e01002. [PMID: 30207083 PMCID: PMC6192409 DOI: 10.1002/brb3.1002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 03/18/2018] [Accepted: 04/15/2018] [Indexed: 11/06/2022] Open
Abstract
INTRODUCTION Ventriculo-peritoneal cerebrospinal fluid (CSF) shunt is the most common method of treating pediatric hydrocephalus. The Codman microadjustable valve (CMAV) is a CSF shunt constructed for children. The objective of the study was (a) to analyze complications after insertion of a CMAV shunt in hydrocephalic children, (b) to analyze complications after replacing a CMAV by an adult-type Codman Hakim adjustable valve shunt (CHAV), and to (c) analyze the in vitro characteristics of the CMAV shunt and correlate the findings with the clinical performance of the shunt. METHODS A retrospective study analyzed a cohort of hydrocephalic children who had received a CMAV shunt and later replaced by a CHAV shunt. We report on the complications that resulted from replacing the CMAV with the CHAV. We tested six CMAV shunts with or without an antisiphon device (ASD) in which opening pressure, resistance, sensitivity to abdominal pressure, ASD position dependency, and function were determined. The test results were correlated with the clinical performance of the shunt in the retrospective study. RESULTS Thirty-seven children (19 boys, 18 girls) were identified. Within the first month after shunt placement, a total of 10 patients (27%) developed complications including infections, hygromas, and shunt dysfunction. Shunt survival varied from 1 week to 145 months. Over the 10-year follow-up period, 13 children had their shunts replaced, six of them with a CHAV without any further complications. A bench test of the CMAV was done to test whether the opening pressure was in agreement with the manufacturer's specifications. Our results were generally in agreement with specifications stated by the manufacturer. CONCLUSION Replacing a CMAV with a CHAV was well tolerated by the patients. Bench test results were generally in agreement with manufacturers specifications. Replacing a CMAV with a CHAV in pediatric hydrocephalus patients can be accomplished safely.
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Affiliation(s)
- Axel Sandvig
- Department of Pharmacology and Clinical Neurosciences, Division of Neuro, Head and Neck, Umeå University, Umeå, Sweden.,Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway
| | - Kai Arnell
- Department of Surgery, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Pharmacology and Clinical Neurosciences, Division of Neuro, Head and Neck, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Lars-Owe D Koskinen
- Department of Pharmacology and Clinical Neurosciences, Division of Neuro, Head and Neck, Umeå University, Umeå, Sweden
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Abstract
SummaryWe measured concentrations of the natural anticoagulant protein C; its cofactor, protein S; and the carrier protein C4bbinding protein (C4BP), in 24 patients with severe infection and 13 with septic shock. Decreased antithrombin III levels were found in 16 of 24 infection patients and all shock patients; high thrombin-antithrombin (TAT) complexes were present in 16 of 24 infection and 12 of 13 shock patients. Protein C concentrations were significantly reduced compared to healthy blood donors, to 60 ± 14% (infection) and 47 ± 20% (septic shock) (mean ± 1 SD). Total protein S levels were not reduced (119 ± 36.7 and 88 ± 20.0%, normal value 96±15%). Free protein S was also normal (27 ± 9.4 and 30 ± 8.7%, normal value 29 ± 9%). The percentage free of total protein S was normal in shock patients (35 ± 8.5%), but significantly reduced in patients without shock (23 ± 5.3%). C4BP was significantly higher than normal in the latter group (135 ± 43%), but not in the shock group (118 ± 40%), possibly due to increased consumption. Thus, no deficiency of total or free protein S was found in these patients, who had evidence of activated coagulation but no clinical DIC.
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Affiliation(s)
- J F Hesselvik
- The Department of Anaesthesiology, University Hospital, Linköping, Sweden
| | - J Malm
- The Department of Clinical Chemistry, University of Lund, Malmö General Hospital, Stockholm, Sweden
| | - B Dahlbäck
- The Department of Clinical Chemistry, University of Lund, Malmö General Hospital, Stockholm, Sweden
| | - M Blombäck
- The Department of Clinical Chemistry and Blood Coagulation, Karolinska lnstitute, Stockholm, Sweden
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50
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Lindén C, Qvarlander S, Jóhannesson G, Johansson E, Östlund F, Malm J, Eklund A. Reply. Ophthalmology 2018; 125:e43-e44. [DOI: 10.1016/j.ophtha.2018.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 01/08/2018] [Indexed: 10/16/2022] Open
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