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The impact of cerebral vasomotor reactivity on cerebrovascular diseases and cognitive impairment. J Neural Transm (Vienna) 2022; 129:1321-1330. [PMID: 36205784 PMCID: PMC9550758 DOI: 10.1007/s00702-022-02546-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 09/19/2022] [Indexed: 11/10/2022]
Abstract
The regulation of cerebral blood flow (CBF) is a complex and tightly controlled function ensuring delivery of oxygen and nutrients and removal of metabolic wastes from brain tissue. Cerebral vasoreactivity (CVR) refers to the ability of the nervous system to regulate CBF according to metabolic demands or changes in the microenvironment. This can be assessed through a variety of nuclear medicine and imaging techniques and protocols. Several studies have investigated the association of CVR with physiological and pathological conditions, with particular reference to the relationship with cognitive impairment and cerebrovascular disorders (CVD). A better understanding of the interaction between CVR and cognitive dysfunction in chronic and particularly acute CVD could help improving treatment and rehabilitation strategies in these patients. In this paper, we reviewed current knowledge on CVR alterations in the context of acute and chronic CVD and cognitive dysfunction. Alterations in CVR and hemodynamics have been described in patients with both neurodegenerative and vascular cognitive impairment, and the severity of these alterations seems to correlate with CVR derailment. Furthermore, an increased risk of cognitive impairment progression has been associated with alterations in CVR parameters and hemodynamics. Few studies have investigated these associations in acute cerebrovascular disorders and the results are inconsistent; thus, further research on this topic is encouraged.
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Beishon L, Panerai RB, Robinson TG, Haunton VJ. Cerebral blood flow response rate to task-activation using a novel method can discriminate cognitive impairment from healthy aging. Physiol Meas 2021; 42. [PMID: 34229305 DOI: 10.1088/1361-6579/ac1185] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 07/06/2021] [Indexed: 12/20/2022]
Abstract
Objective.A new method to classify individuals as 'responders' to task-activated cerebral blood flow velocity (CBFv) has recently been developed. This study investigated whether CBFv response rate to task-activation is affected by Alzheimer's disease (AD) and mild cognitive impairment (MCI).Approach.The 95th thresholds for cross correlation function peak and variance ratio were derived from 270 unstimulated, healthy hemispheres, and were used to classify the presence of a response to task-activation. Thresholds were applied to five cognitive tasks (attention, verbal fluency, language, visuospatial, memory) in CBFv data from 30 healthy older adults (HC), 35 AD and 22 MCI participants. Cumulative response rate (CRR) was calculated from the sum of responses across five tasks, for both hemispheres. Area under the curve (AUC) was derived from receiver operating characteristic (ROC) curve analysis.Main results. The number of responders differed significantly between tasks (p < 0.005) and diagnostic groups (p = 0.011). On post hoc tests there were more responders in the visuospatial (79%-90%) compared to fluency (45%-80%), language (50%-77%), and memory (44%-70%) tasks bilaterally, and responders were greater in the HC (70%) compared to AD (41%) and MCI (23%) groups to at least eight out of ten tasks. At an optimal threshold of 7.5 out of 10 responses, the AUC-ROC distinguished HC from AD and MCI with a; sensitivity 66% and specificity 70% (AUC = 0.72).Significance. Using a novel method to classify responders to cognitive task-activation, HC demonstrated a higher CRR than those with MCI or AD, and a threshold of <8 responses distinguished healthy ageing from dementia.
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Affiliation(s)
- Lucy Beishon
- University of Leicester, Department of Cardiovascular Sciences, Leicester, United Kingdom
| | - Ronney B Panerai
- University of Leicester, Department of Cardiovascular Sciences, Leicester, United Kingdom.,NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, United Kingdom
| | - Thompson G Robinson
- University of Leicester, Department of Cardiovascular Sciences, Leicester, United Kingdom.,NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, United Kingdom
| | - Victoria J Haunton
- University of Leicester, Department of Cardiovascular Sciences, Leicester, United Kingdom.,NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, United Kingdom
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Siniscalchi A, Gray C, Malferrari G. Ultrasound Diagnostic Method in Vascular Dementia: Current Concepts. Curr Med Imaging 2021; 17:507-512. [PMID: 33032514 DOI: 10.2174/1573405616999201008145106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 07/20/2020] [Accepted: 08/05/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND Increasing interest in identifying cerebral hemodynamics alterations as a cause of possible onset or worsening of cognitive impairment in elderly patients with vascular risk factors. INTRODUCTION Intracranial ultrasound is a non-invasive, repeatable inexpensive method for recording variation of the cerebral vascular tree in physiological and pathological conditions and the diagnosis of vascular dementia (VaD). METHODS PubMed, Embase, Cochrane library and reference lists have been searched for articles published until March 30, 2020. RESULTS Clinical studies reported different Transcranial Doppler (TCD) parameters and subsequently transcranial duplex with color code (TCCD) in patients affected by vascular dementia. The number of studies using TCCD remains limited and most of the available data are still based on TCD. However, the use of transcranial Doppler could better stratify elderly patients with initial signs of cognitive impairment. CONCLUSION Intracranial ultrasound employment to detect cerebral hemodynamic changes in VaD patients has been briefly discussed in this review.
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Affiliation(s)
- Antonio Siniscalchi
- Department of Neurology and Stroke Unit, Annunziata Hospital of Cosenza, Cosenza, Italy
| | - Cleona Gray
- Vascular and Endovascular Surgery Unit, Mater Misericordiae University Hospital, Dublin, Ireland
| | - Giovanni Malferrari
- Stroke Unit, Neurology Unit, Azienda Unità Sanitaria Locale - IRCCS, Reggio Emilia, Italy
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Beishon LC, Panerai RB, Budgeon C, Subramaniam H, Mukaetova-Ladinska E, Robinson TG, Haunton VJ. The Cognition and Flow Study: A Feasibility Randomized Controlled Trial of the Effects of Cognitive Training on Cerebral Blood Flow. J Alzheimers Dis 2021; 80:1567-1581. [PMID: 33720895 DOI: 10.3233/jad-201444] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Cognitive training (CT) has demonstrated benefits for healthy older adults (HG) and mild cognitive impairment (MCI), but the effects on vascular function are unknown. OBJECTIVE This is a feasibility trial investigating the effects of CT on cerebral blood flow velocity (CBFv). METHODS Twenty HG, 24 with Alzheimer's disease (AD), and 12 with MCI were randomized to 12 weeks of multi-domain CT or control. Outcomes included: cognition (Addenbrooke's Cognitive Examination III), mood, quality of life (QoL), physical, and neurovascular function (transcranial Doppler ultrasonography measured task activation of CBFv responses). Data are presented as mean difference (MD) and 95% confidence interval (CI). RESULTS 47 participants completed the trial. There were three dropouts from the training arm in the AD group, and one in the HG group. The intervention was acceptable and feasible to the majority of participants with a high completion rate (89%). The dropout rate was higher among participants with dementia. Few changes were identified on secondary analyses, but QoL was significantly improved in HG post-training (MD: 4.83 [95% CI: 1.13, 8.54]). CBFv response rate was not significantly different in HG (MD: 1.84 [95% CI: -4.81, 1.12]), but a significant increase was seen in the patient group (MD: 1.79 [95% CI: 0.005, 3.58]), requiring sample sizes of 56 and 84 participants respectively for a fully-powered trial. CONCLUSION A 12-week CT program was acceptable and feasible in HG, AD, and MCI. CT may be associated with alterations in vascular physiology which require further investigation in an appropriately powered randomized controlled trial.
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Affiliation(s)
- Lucy C Beishon
- University of Leicester, Department of Cardiovascular Sciences, Leicester, UK
| | - Ronney B Panerai
- University of Leicester, Department of Cardiovascular Sciences, Leicester, UK.,NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
| | - Charley Budgeon
- University of Leicester, Department of Cardiovascular Sciences, Leicester, UK.,School of Population and Global Health, University of Western Australia, Perth, Australia
| | - Hari Subramaniam
- The Evington Centre, Leicestershire Partnership NHS Trust, Leicester, UK
| | - Elizabeta Mukaetova-Ladinska
- The Evington Centre, Leicestershire Partnership NHS Trust, Leicester, UK.,University of Leicester, Department of Neuroscience, Psychology and Behaviour, Leicester, UK
| | - Thompson G Robinson
- University of Leicester, Department of Cardiovascular Sciences, Leicester, UK.,NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
| | - Victoria J Haunton
- University of Leicester, Department of Cardiovascular Sciences, Leicester, UK.,NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
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Gutteridge DS, Saredakis D, Badcock NA, Collins-Praino LE, Keage HAD. Cerebrovascular function during cognition in Parkinson's disease: A functional transcranial Doppler sonography study. J Neurol Sci 2019; 408:116578. [PMID: 31751909 DOI: 10.1016/j.jns.2019.116578] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/21/2019] [Accepted: 11/11/2019] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Recent evidence has linked cerebrovascular abnormalities with Parkinson's Disease (PD), which may provide a new neurophysiological understanding of cognitive impairment in PD. The current study aimed to compare cerebrovascular functioning, during a cognitive task and at rest, in those with and without PD. METHODS Idiopathic PD patients (n = 30) and age- and gender-matched healthy controls (n = 30) undertook cognitive testing and completed a word generation task while blood flow velocity was monitored bilaterally with functional transcranial Doppler sonography (fTCD) of the middle cerebral arteries. The lateralisation index and its standard deviation and timing, along with the maximum peak velocity for the left and right hemispheres and their latencies and standard deviations, were calculated for each participant. RESULTS The PD patients showed significantly more variability of the lateralisation index compared to the control group; but there were no differences in the lateralisation index itself nor in the peak velocities. In the PD group, the variability in the peak velocities showed significant positive correlations with performance on executive function tests. CONCLUSION Normal ageing has been associated with a reduction in the lateralisation index, but no alterations in the standard deviation, suggesting that cerebrovascular functional changes associated with PD differ from those of typical ageing. The within-subject variability observed in the PD group indicate abnormalities within the neurovascular coupling response. Further, the association between the within-subject variability and executive functioning in the PD group, suggests that cerebrovascular dysfunction plays an important role in cognitive impairment in PD.
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Affiliation(s)
- Daria S Gutteridge
- Cognitive Ageing and Impairment Neurosciences Laboratory, School of Psychology, Social Work and Social Policy, University of South Australia, Australia.
| | - Dimitrios Saredakis
- Cognitive Ageing and Impairment Neurosciences Laboratory, School of Psychology, Social Work and Social Policy, University of South Australia, Australia
| | - Nicholas A Badcock
- ARC Centre of Excellence in Cognition and its Disorders, Department of Cognitive Science, Macquarie University, Australia
| | - Lyndsey E Collins-Praino
- Cognition, Ageing and Neurodegenerative Disease Laboratory, Adelaide Medical School, University of Adelaide, Australia
| | - Hannah A D Keage
- Cognitive Ageing and Impairment Neurosciences Laboratory, School of Psychology, Social Work and Social Policy, University of South Australia, Australia
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Bian Y, Wang JC, Sun F, Sun ZY, Lin YJ, Liu Y, Zhao B, Liu L, Luo XG. Assessment of cerebrovascular reserve impairment using the breath-holding index in patients with leukoaraiosis. Neural Regen Res 2019; 14:1412-1418. [PMID: 30964067 PMCID: PMC6524493 DOI: 10.4103/1673-5374.251332] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Many studies have demonstrated that leukoaraiosis is associated with impaired cerebrovascular reserve function. However, the definitive hemodynamic changes that occur in leukoaraiosis are not clear, and there are many controversies. This study aimed to investigate hemodynamic changes in symptomatic leukoaraiosis using transcranial Doppler ultrasonography and the breath-holding test in a Chinese Han population, from northern China. A total of 203 patients who were diagnosed with ischemic stroke or clinical chronic progressive ischemic symptoms were enrolled in this study, including 97 males and 106 females, with an age range of 43–93 years. The severity of leukoaraiosis was evaluated according to the Fazekas grading scale, and patients were divided into four groups accordingly. Grade 0 was no leukoaraiosis, and grades I, II, and III were mild, moderate, and severe leukoaraiosis, respectively, with 44, 79, 44, and 36 cases in each group. Transcranial Doppler ultrasonography and the breath-holding test were performed. The mean blood flow velocity of the bilateral middle cerebral artery was measured and the breath-holding index was calculated. The breath holding index was correlated with leukoaraiosis severity and cognitive impairment. Patients with a low breath holding index presented poor performance in the Montreal Cognitive Assessment (MoCA) and executive function tests. That is, the lower the breath holding index, the lower the scores for the MoCA and the higher for the trail-making test Parts A and B. These results indicate that the breath-holding index is a useful parameter for the evaluation of cerebrovascular reserve impairment in patients with leukoaraiosis. In addition, the breath-holding index can reflect cognitive dysfunction, providing a new insight into the pathophysiology of leukoaraiosis. This study was approved by the Ethics Committee of the Fifth People’s Hospital of Shenyang, China (approval No. 20160301) and registered in the Chinese Clinical Trial Registry (registration number: ChiCTR1800014421).
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Affiliation(s)
- Ying Bian
- Department of Neurology, the First Affiliated Hospital of China Medical University; Department of Neurology, the Fifth People's Hospital of Shenyang, Shenyang, Liaoning Province, China
| | - Jin-Chun Wang
- Department of Neurology, the Fifth People's Hospital of Shenyang, Shenyang, Liaoning Province, China
| | - Feng Sun
- Department of Neurology, the Fifth People's Hospital of Shenyang, Shenyang, Liaoning Province, China
| | - Zi-Yi Sun
- Department of Endocrinology, Shengjing Hospital, China Medical University, Shenyang, Liaoning Province, China
| | - Yu-Jiao Lin
- Department of Neurology, the Fifth People's Hospital of Shenyang, Shenyang, Liaoning Province, China
| | - Yang Liu
- Department of Neurology, the First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, China
| | - Bin Zhao
- Department of Neurology, the Fifth People's Hospital of Shenyang, Shenyang, Liaoning Province, China
| | - Li Liu
- Department of Neurology, the Fifth People's Hospital of Shenyang, Shenyang, Liaoning Province, China
| | - Xiao-Guang Luo
- Department of Neurology, the First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, China
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Beishon LC, Panerai RB, Robinson TG, Subramaniam H, Haunton VJ. The Assessment of Cerebrovascular Response to a Language Task from the Addenbrooke's Cognitive Examination in Cognitive Impairment: A Feasibility Functional Transcranial Doppler Ultrasonography Study. J Alzheimers Dis Rep 2018; 2:153-164. [PMID: 30480258 PMCID: PMC6218154 DOI: 10.3233/adr-180068] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: The incidence of dementia is predicted to rise rapidly, but sensitive diagnostic tests remain elusive. Changes in cerebral blood flow velocity (CBFv) can occur at an early stage of cognitive decline, and can be measured by transcranial Doppler ultrasonography (TCD). Objective: The aim of this study was to characterize the CBFv changes that occur in healthy older adults (HC), mild cognitive impairment (MCI), and Alzheimer’s disease (AD), in response to a language task from the Addenbrooke’s cognitive examination (ACE-III). Methods: Participants underwent bilateral TCD, continuous heart rate (ECG), end-tidal CO2 (capnography, ETCO2), and beat-to-beat blood pressure (Finometer, MAP), monitoring, during a 5-minute baseline, followed by cognitive tasks from the ACE-III. Data are presented for a language task (repeating words and phrases aloud), as peak percentage change in CBFv, HR, MAP, and ETCO2 from a normalized baseline. Results: 30 participants (mean age 73.2 years, 20% female) were recruited; HC (n = 10), MCI (n = 10), AD (n = 10). Language scores did not differ between groups (p = 0.16). Peak percentage change in CBFv differed between groups with the language task (HC: 15.9 (7.5)%, MCI: 6.7 (4.5)%, AD: 0.1 (7.1)%; p < 0.005). However, changes in MAP (HC: 7.9 (4.6)%, MCI: –0.1 (0.9)%, AD: 0.9 (4.4)%; p < 0.005), HR (HC: 8.8 (8.2)%, MCI: 0.7 (4.3)%, AD: –0.5 (5.6)%; p = 0.005), and ETCO2 (HC: –0.9 (3.2)%, MCI: 0.9 (3.2)%, AD: –5.2 (5.7)%; p = 0.006), also occurred. Conclusions: TCD measured CBFv changes to a language task from the ACE-III was feasible in a cognitively impaired population, further work is required in a larger population.
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Affiliation(s)
- Lucy C Beishon
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Ronney B Panerai
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
| | - Thompson G Robinson
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
| | - Hari Subramaniam
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,Leicestershire Partnership Trust, Evington Centre, Gwendolen Road, Leicester, UK
| | - Victoria J Haunton
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,NIHR Leicester Biomedical Research Centre, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
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Beishon LC, Williams CAL, Panerai RB, Robinson TG, Haunton VJ. The assessment of neurovascular coupling with the Addenbrooke’s Cognitive Examination: a functional transcranial Doppler ultrasonographic study. J Neurophysiol 2018; 119:1084-1094. [DOI: 10.1152/jn.00698.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Cerebrovascular dysfunction occurs early in dementia and can be identified by transcranial Doppler ultrasonography (TCD). Few studies have examined cerebral blood flow velocity (CBFv) responses to a detailed cognitive battery. This study aimed to characterize all CBFv responses, and the effect of hemispheric dominance, to the Addenbrooke’s Cognitive Examination (ACE-III) in healthy volunteers. Forty volunteers underwent continuous bilateral TCD, beat-to-beat blood pressure (MAP; Finapres), heart rate (HR; electrocardiogram), and end-tidal CO2 (ETCO2; capnography) monitoring. After a 5-min baseline period, all tasks from the ACE-III were performed in 3 sections (A: attention, fluency, memory; B: language; C: visuospatial, memory). Data are population mean normalized percentage (PM%) change from a 20-s baseline period before task initiation. Forty bilateral data sets were obtained (27 women, 37 right-hand dominant). All paradigms produced a sharp increase in CBFv in both dominant (PM% range: 3.29 to 9.70%) and nondominant (PM% range: 4.34 to 11.63%) hemispheres at task initiation, with associated increases in MAP (PM% range: 3.06 to 16.04%). ETCO2 did not differ significantly at task initiation (PM% range: −1.1 to 2.4%, P > 0.05). HR differed significantly across A and C tasks at initiation (PM% range: −1.1 to 2.4%, P < 0.05), but not B tasks. In conclusion, all tasks resulted in increases in CBFv, differing significantly between paradigms. These results require further investigation in a cognitively impaired population. NEW & NOTEWORTHY This study is the first to provide a normative data set of cerebral blood flow velocity (CBFv) responses to a complete cognitive assessment (Addenbrooke’s Cognitive Examination, ACE-III) in a large sample ( n = 40) of healthy volunteers. All tasks produced peak and sustained increases in CBFv to different extents. The ACE-III is a feasible tool to assess neurovascular coupling with transcranial Doppler ultrasonography. These data can be used to inform the most appropriate cognitive task to elicit CBFv responses for future studies.
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Affiliation(s)
- Lucy C. Beishon
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Claire A. L. Williams
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Ronney B. Panerai
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- NIHR Leicester Biomedical Research Centre, University of Leicester, Leicester, United Kingdom
| | - Thompson G. Robinson
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- NIHR Leicester Biomedical Research Centre, University of Leicester, Leicester, United Kingdom
| | - Victoria J. Haunton
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- NIHR Leicester Biomedical Research Centre, University of Leicester, Leicester, United Kingdom
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Badcock NA, Spooner R, Hofmann J, Flitton A, Elliott S, Kurylowicz L, Lavrencic LM, Payne HM, Holt GK, Holden A, Churches OF, Kohler MJ, Keage HAD. What Box: A task for assessing language lateralization in young children. Laterality 2017; 23:391-408. [PMID: 28803507 DOI: 10.1080/1357650x.2017.1363773] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The assessment of active language lateralization in infants and toddlers is challenging. It requires an imaging tool that is unintimidating, quick to setup, and robust to movement, in addition to an engaging and cognitively simple language processing task. Functional Transcranial Doppler Ultrasound (fTCD) offers a suitable technique and here we report on a suitable method to elicit active language production in young children. The 34-second "What Box" trial presents an animated face "searching" for an object. The face "finds" a box that opens to reveal a to-be-labelled object. In a sample of 95 children (1 to 5 years of age), 81% completed the task-32% with ≥10 trials. The task was validated (ρ = 0.4) against the gold standard Word Generation task in a group of older adults (n = 65, 60-85 years of age), though was less likely to categorize lateralization as left or right, indicative of greater measurement variability. Existing methods for active language production have been used with 2-year-old children while passive listening has been conducted with sleeping 6-month-olds. This is the first active method to be successfully employed with infants through to pre-schoolers, forming a useful tool for populations in which complex instructions are problematic.
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Affiliation(s)
- Nicholas A Badcock
- a ARC Centre for Excellence in Cognition and its Disorders, Department of Cognitive Science , Macquarie University , North Ryde , New South Wales , Australia
| | - Rachael Spooner
- b Cognitive Neuroscience Laboratory, School of Psychology, Social Work and Social Policy , University of South Australia , South Australia , Australia
| | - Jessica Hofmann
- c Cognitive Ageing and Impairment Neurosciences Laboratory, School of Psychology, Social Work and Social Policy , University of South Australia , South Australia , Australia
| | - Atlanta Flitton
- c Cognitive Ageing and Impairment Neurosciences Laboratory, School of Psychology, Social Work and Social Policy , University of South Australia , South Australia , Australia
| | - Scott Elliott
- c Cognitive Ageing and Impairment Neurosciences Laboratory, School of Psychology, Social Work and Social Policy , University of South Australia , South Australia , Australia
| | - Lisa Kurylowicz
- c Cognitive Ageing and Impairment Neurosciences Laboratory, School of Psychology, Social Work and Social Policy , University of South Australia , South Australia , Australia.,d Department of General Paediatrics , University Children's Hospital Bonn , Bonn , Germany
| | - Louise M Lavrencic
- c Cognitive Ageing and Impairment Neurosciences Laboratory, School of Psychology, Social Work and Social Policy , University of South Australia , South Australia , Australia
| | - Heather M Payne
- e Deafness, Cognition, and Language Research Centre , University College London , London , UK.,f Institute of Cognitive Neuroscience , University College London , London , UK
| | - Georgina K Holt
- g Oxford Study of Children's Communication Impairments, Department of Experimental Psychology , University of Oxford , Oxford , UK
| | - Anneka Holden
- g Oxford Study of Children's Communication Impairments, Department of Experimental Psychology , University of Oxford , Oxford , UK
| | - Owen F Churches
- h Brain and Cognition Laboratory , Flinders University , South Australia , Australia
| | - Mark J Kohler
- b Cognitive Neuroscience Laboratory, School of Psychology, Social Work and Social Policy , University of South Australia , South Australia , Australia
| | - Hannah A D Keage
- c Cognitive Ageing and Impairment Neurosciences Laboratory, School of Psychology, Social Work and Social Policy , University of South Australia , South Australia , Australia
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10
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Williams C, Panerai R, Robinson T, Haunton V. Transcranial Doppler ultrasonography in the assessment of neurovascular coupling responses to cognitive examination in healthy controls: A feasibility study. J Neurosci Methods 2017; 284:57-62. [DOI: 10.1016/j.jneumeth.2017.04.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 04/21/2017] [Accepted: 04/22/2017] [Indexed: 11/29/2022]
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11
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Malojcic B, Giannakopoulos P, Sorond FA, Azevedo E, Diomedi M, Oblak JP, Carraro N, Boban M, Olah L, Schreiber SJ, Pavlovic A, Garami Z, Bornstein NM, Rosengarten B. Ultrasound and dynamic functional imaging in vascular cognitive impairment and Alzheimer's disease. BMC Med 2017; 15:27. [PMID: 28178960 PMCID: PMC5299782 DOI: 10.1186/s12916-017-0799-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 01/21/2017] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND The vascular contributions to neurodegeneration and neuroinflammation may be assessed by magnetic resonance imaging (MRI) and ultrasonography (US). This review summarises the methodology for these widely available, safe and relatively low cost tools and analyses recent work highlighting their potential utility as biomarkers for differentiating subtypes of cognitive impairment and dementia, tracking disease progression and evaluating response to treatment in various neurocognitive disorders. METHODS At the 9th International Congress on Vascular Dementia (Ljubljana, Slovenia, October 2015) a writing group of experts was formed to review the evidence on the utility of US and arterial spin labelling (ASL) as neurophysiological markers of normal ageing, vascular cognitive impairment (VCI) and Alzheimer's disease (AD). Original articles, systematic literature reviews, guidelines and expert opinions published until September 2016 were critically analysed to summarise existing evidence, indicate gaps in current knowledge and, when appropriate, suggest standards of use for the most widely used US and ASL applications. RESULTS Cerebral hypoperfusion has been linked to cognitive decline either as a risk or an aggravating factor. Hypoperfusion as a consequence of microangiopathy, macroangiopathy or cardiac dysfunction can promote or accelerate neurodegeneration, blood-brain barrier disruption and neuroinflammation. US can evaluate the cerebrovascular tree for pathological structure and functional changes contributing to cerebral hypoperfusion. Microvascular pathology and hypoperfusion at the level of capillaries and small arterioles can also be assessed by ASL, an MRI signal. Despite increasing evidence supporting the utility of these methods in detection of microvascular pathology, cerebral hypoperfusion, neurovascular unit dysfunction and, most importantly, disease progression, incomplete standardisation and missing validated cut-off values limit their use in daily routine. CONCLUSIONS US and ASL are promising tools with excellent temporal resolution, which will have a significant impact on our understanding of the vascular contributions to VCI and AD and may also be relevant for assessing future prevention and therapeutic strategies for these conditions. Our work provides recommendations regarding the use of non-invasive imaging techniques to investigate the functional consequences of vascular burden in dementia.
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Affiliation(s)
- Branko Malojcic
- Department of Neurology, University Hospital Center Zagreb, Zagreb School of Medicine, Kispaticeva 12, 10000, Zagreb, Croatia.
| | | | - Farzaneh A Sorond
- Department of Neurology, Northwestern University Feinberg School of Medicine Chicago, Chicago, IL, USA
| | - Elsa Azevedo
- Department of Neurology, São João Hospital Center and Faculty of Medicine of University of Porto, Porto, Portugal
| | - Marina Diomedi
- Cerebrovascular Disease Center, Stroke Unit, University of Rome Tor Vergata, Rome, Italy
| | - Janja Pretnar Oblak
- Department of Vascular Neurology and Intensive Therapy, University Medical Center Ljubljana, Ljubljana, Slovenia
| | - Nicola Carraro
- Department of Medical Sciences, Clinical Neurology-Stroke Unit, University Hospital, University of Trieste, Trieste, Italy
| | - Marina Boban
- Department of Neurology, University Hospital Center Zagreb, Zagreb School of Medicine, Kispaticeva 12, 10000, Zagreb, Croatia
| | - Laszlo Olah
- Department of Neurology, University of Debrecen, Debrecen, Hungary
| | - Stephan J Schreiber
- Department of Neurology, Charite - Universitätsmedizin Berlin, Berlin, Germany
| | - Aleksandra Pavlovic
- Neurology Clinic, Clinical Center of Serbia, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Zsolt Garami
- Methodist DeBakey Heart and Vascular Center, Houston, TX, USA
| | - Nantan M Bornstein
- Neurology Department, Tel Aviv Sourasky Medical Centre, Tel Aviv, Israel
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12
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Smoliński Ł, Członkowska A. Cerebral vasomotor reactivity in neurodegenerative diseases. Neurol Neurochir Pol 2016; 50:455-462. [PMID: 27553189 DOI: 10.1016/j.pjnns.2016.07.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 07/26/2016] [Accepted: 07/28/2016] [Indexed: 11/26/2022]
Abstract
Small-caliber cerebral vessels change their diameters in response to alterations of key metabolite concentrations such as carbon dioxide or oxygen. This phenomenon, termed the cerebral vasomotor reactivity (CVMR), is the basis for blood flow regulation in the brain in accordance with its metabolic status. Typically, CVMR is determined as the amount of change in cerebral blood flow in response to a vasodilating stimulus, which can be measured by various neuroimaging methods or by transcranial Doppler. It has been shown that CVMR is impaired in cerebrovascular diseases, but there is also evidence of a similar dysfunction in neurodegenerative disorders. Here, we review studies that have investigated CVMR in the common neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and multiple sclerosis. Moreover, we discuss potential neurodegenerative mechanisms responsible for the impairment of CVMR.
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Affiliation(s)
- Łukasz Smoliński
- Second Department of Neurology, Institute of Psychiatry and Neurology, Warsaw, Poland
| | - Anna Członkowska
- Second Department of Neurology, Institute of Psychiatry and Neurology, Warsaw, Poland; Department of Clinical and Experimental Pharmacology, Medical University of Warsaw, Warsaw, Poland.
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13
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Urbanova B, Tomek A, Mikulik R, Magerova H, Horinek D, Hort J. Neurosonological Examination: A Non-Invasive Approach for the Detection of Cerebrovascular Impairment in AD. Front Behav Neurosci 2014; 8:4. [PMID: 24478651 PMCID: PMC3896883 DOI: 10.3389/fnbeh.2014.00004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 01/03/2014] [Indexed: 12/27/2022] Open
Abstract
There has been a growing interest in vascular impairment associated with Alzheimer’s disease (AD). This interest was stimulated by the findings of higher incidence of vascular risk factors in AD. Signs of vascular impairment were investigated notably in the field of imaging methods. Our aim was to explore ultrasonographic studies of extra- and intracranial vessels in patients with AD and mild cognitive impairment (MCI) and define implications for diagnosis, treatment, and prevention of the disease. The most frequently studied parameters with extracranial ultrasound are intima-media thickness in common carotid artery, carotid atherosclerosis, and total cerebral blood flow. The transcranial ultrasound concentrates mostly on flow velocities, pulsatility indices, cerebrovascular reserve capacity, and cerebral microembolization. Studies suggest that there is morphological and functional impairment of cerebral circulation in AD compared to healthy subjects. Ultrasound as a non-invasive method could be potentially useful in identifying individuals in a higher risk of progression of cognitive decline.
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Affiliation(s)
- Barbora Urbanova
- Department of Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University , Prague , Czech Republic
| | - Ales Tomek
- Department of Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University , Prague , Czech Republic
| | - Robert Mikulik
- Department of Neurology, International Clinical Research Center, St. Anne's University Hospital , Brno , Czech Republic
| | - Hana Magerova
- Department of Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University , Prague , Czech Republic
| | - Daniel Horinek
- Department of Neurosurgery, 1st Faculty of Medicine, Central Military Hospital, Charles University , Prague , Czech Republic ; International Clinical Research Center, St. Anne's University Hospital , Brno , Czech Republic
| | - Jakub Hort
- Department of Neurology, 2nd Faculty of Medicine, Motol University Hospital, Charles University , Prague , Czech Republic ; International Clinical Research Center, St. Anne's University Hospital , Brno , Czech Republic
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14
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Kemény V, Molnár S, Andrejkovics M, Makai A, Csiba L. Acute and Chronic Effects of Vinpocetine on Cerebral Hemodynamics and Neuropsychological Performance in Multi-infarct Patients. J Clin Pharmacol 2013; 45:1048-54. [PMID: 16100299 DOI: 10.1177/0091270005279363] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A double-blind, prospective, randomized, placebo-controlled clinical trial was carried out to test the acute and long-term hemodynamical and beneficial cognitive effects of the vasoactive agent vinpocetine on patients suffering from multiple cerebral infarcts by means of functional transcranial Doppler examinations and by neuropsychological tests. Twenty-six patients (17 men, 9 women) with multiple cerebral infarctions, aged between 50 and 83 years (mean age+/-SD=63.4+/-9.39 years) were examined, 14 of whom received vinpocetine and 12 placebo. The functional transcranial Doppler included breath-holding tests, finger movement, word fluency, and picture-discrimination tasks. Twenty-five patients were assessed by neuropsychological battery. No serious side effect was found in the vinpocetine group. The flow velocities were significantly lower in the acute phase after breath holding in the vinpocetine group than in the placebo group. Three months later, the vinpocetine patients did not show any significant worsening in digit span backward test, while the placebo group did. No other significant differences in the neuropsychological test could be detected between the treatment and the placebo groups. Longer lasting and higher dosage of vinpocetine therapy is suggested to prove its potential effect.
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Affiliation(s)
- Vendel Kemény
- Department of Neurology, PM Flór Ferenc County Hospital, H-2143 Kistarcsa, and Department of Neurology, University of Debrecen, Hungary
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15
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Keage HAD, Churches OF, Kohler M, Pomeroy D, Luppino R, Bartolo ML, Elliott S. Cerebrovascular function in aging and dementia: a systematic review of transcranial Doppler studies. Dement Geriatr Cogn Dis Extra 2012; 2:258-70. [PMID: 22822408 PMCID: PMC3398823 DOI: 10.1159/000339234] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Background/Aim The contribution of cerebrovascular dysfunction to the manifestation of dementia and cognitive decline in late life is gaining increased attention. We aimed to systematically review evidence for associations between dementia or aging and cerebrovascular function as measured using transcranial Doppler (TCD) examination. Methods A total of 1,172 articles were retrieved from PsychInfo and PubMed searches, and 34 relevant articles were identified using a variety of TCD methods. Results The pulsatility index (vessel resistance), spontaneous emboli and cerebrovascular reactivity to hyper-/hypocapnia appeared good discriminators of dementia. Aging was associated with a slowing in blood flow velocity. Conclusion TCD ultrasonography is inexpensive, portable and well tolerated by aged and demented subjects. The technique stands to make a valuable contribution to the knowledge regarding the underlying functional biology of age-related cognitive change and dementia.
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Affiliation(s)
- Hannah A D Keage
- Cognitive Neuroscience Laboratory, School of Psychology, Social Work and Social Policy, Adelaide, S.A., Australia
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16
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Anzola GP, Galluzzi S, Mazzucco S, Frisoni GB. Autonomic dysfunction in mild cognitive impairment: a transcranial Doppler study. Acta Neurol Scand 2011; 124:403-9. [PMID: 22017634 DOI: 10.1111/j.1600-0404.2011.01495.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES The contribution of early microvascular and autonomic derangements to the pathogenesis of mild cognitive impairment (MCI) is unclear. Aim of this study is to evaluate cerebrovascular reactivity (CVR) and cardiac autonomic function in patients with MCI by means of transcranial Doppler (TCD). MATERIAL AND METHODS Fifteen patients with MCI and 28 controls underwent carotid ultrasound and TCD evaluation, including assessment of mean flow velocity (MFV) in the middle cerebral artery at baseline, after CO(2) inhalation and after hyperpnoea. End-tidal CO(2) , mean arterial blood pressure (MAP), heart rate (HR), and respiratory rate were monitored throughout the procedure, and CVR was calculated. RESULTS MAP, end-tidal CO(2) , and MFV variations during hypercapnia and hyperventilation showed no between-group differences. CVR was similar in controls and MCI (2.30 vs 2,39, respectively, P = 0.767). HR significantly increased in hypercapnia (+9.4%, P < 0.0001) and hyperventilation (+18.7%, P < 0.0001) in controls, while in MCI it significantly increased in hyperventilation (+10.4%, P = 0.002), but not in hypercapnia (+1.1%, P = 0.635). CONCLUSIONS This study demonstrates that patients with MCI have a normal CVR, but they exhibit signs of autonomic dysfunction after CO(2) challenge. Should this finding be confirmed in larger studies, HR response to CO(2) challenge could become a marker of MCI.
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Affiliation(s)
- G P Anzola
- Service of Neurology, S. Orsola Hospital, Brescia, Italy.
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Jurasic MJ, Popovic IM, Morovic S, Trkanjec Z, Seric V, Demarin V. Can beta stiffness index be proposed as risk factor for dementia. J Neurol Sci 2009; 283:13-6. [PMID: 19286194 DOI: 10.1016/j.jns.2009.02.339] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND AND AIM Changes of arterial stiffness indicate alteration in arterial mechanics predisposing to the evolution of stroke or vascular dementia. The aim of this pilot study was to investigate whether ultrasound parameters, particularly beta stiffness index (BSI), should be further explored as independent markers or risk factors for dementia. PATIENTS AND METHODS There were 38 demented patients included in this study (72.53+/-7.87 yrs) and 33 clinically healthy controls (68.85+/-3.52 yrs). Risk factors were noted and ultrasound measurements performed on common carotid artery (CCA) using eTracking software on Aloka ProSound ALPHA 10 with 13 MHz linear probe. Level of significance was p<0.05. RESULTS Arterial hypertension was present in 24 patients, atrial fibrillation in 9, diabetes in 3, and hypercholesterolemia in 18. Hypertension was present as a single risk factor in 15 controls with average diastolic blood pressure significantly lower in patients. Significantly higher in patients were mean intima-media thickness, systolic and diastolic CCA diameters (CD), and mean BSI in CCA bilaterally. Linear regression analysis for groups of Alzheimer's dementia and vascular dementia proved that MMSE of the two groups relates to CCA diameter change (CDc) and BSI change explaining up to 5% of variability. CONCLUSIONS CD, CDc and BSI should be monitored in patients with cognitive decline and further explored as possible independent markers or risk factors; in future studies groups of demented and non-demented patients should be age, sex and risk factor matched.
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Affiliation(s)
- Miljenka-Jelena Jurasic
- University Department of Neurology, Sestre Milosrdnice University Hospital, Vinogradska 29, 10 000 Zagreb, Croatia.
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18
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Asil T, Uzuner N. Differentiation of vascular dementia and Alzheimer disease: a functional transcranial Doppler ultrasonographic study. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2005; 24:1065-70. [PMID: 16040820 DOI: 10.7863/jum.2005.24.8.1065] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
OBJECTIVE In brain perfusion studies, perfusion defects have been reported mainly in the temporal and parietal regions in patients with Alzheimer disease (AD), but it is known that the occipital cortex is partially preserved from metabolic defects in patients with AD, at least in the early stage of the disease. We therefore evaluated the reactivity of the posterior cerebral arteries during visual stimulation with transcranial Doppler ultrasonography (TDU). METHODS Fifteen patients with AD (mean age, 70 years), 12 patients with vascular dementia (VD) (mean age, 61.5 years), and 9 healthy control subjects (mean age, 58 years) were enrolled in the study. The reactivity of both posterior cerebral arteries during visual stimulation was measured with TDU. Reactivity was calculated by the differences in mean relative blood flow velocity (rBFv) between stimulation (vs) and rest (vr) divided by the resting value [rBFv = 100 x (vs - vr)/vr]. RESULTS Significant increases of vascular reactivity were obtained during visual stimulation for each group (P < .001). There was no significant right or left side difference for vascular reactivity within the groups except in VD; therefore, values of the right and left sides were pooled for patients with AD and control subjects. Reactivity to visual stimulation was similar for the patients with AD (mean +/- SD, 38% +/- 2.2%) and control subjects (35% +/- 1.8%), but reactivity was found significantly decreased in both sides of patients with VD (25.7% +/- 2.1% for the left side and 24% +/- 2.6% for the right side) compared with the healthy control subjects and the patients with AD (P < .001). CONCLUSIONS These results indicate that the occipital cortex is partially preserved in patients with AD and that functional TDU may be a valuable tool for differentiating VD and AD.
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Affiliation(s)
- Talip Asil
- Department of Neurology, Faculty of Medicine, University of Trakya, Edirne, Turkey.
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Ruitenberg A, den Heijer T, Bakker SLM, van Swieten JC, Koudstaal PJ, Hofman A, Breteler MMB. Cerebral hypoperfusion and clinical onset of dementia: the Rotterdam Study. Ann Neurol 2005; 57:789-94. [PMID: 15929050 DOI: 10.1002/ana.20493] [Citation(s) in RCA: 527] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Cerebral blood flow (CBF) velocity is decreased in patients with Alzheimer's disease. It is being debated whether this reflects diminished demand because of advanced neurodegeneration or that cerebral hypoperfusion contributes to dementia. We examined the relation of CBF velocity as measured with transcranial Doppler with dementia and markers of incipient dementia (ie, cognitive decline and hippocampal and amygdalar atrophy on magnetic resonance imaging) in 1,730 participants of the Rotterdam Study aged 55 years and older. Cognitive decline in the 6.5 years preceding CBF velocity measurement was assessed with repeated Mini-Mental State Examinations in nondemented subjects (n = 1,716). Hippocampal and amygdalar volumes were assessed in a subset of 170 nondemented subjects. Subjects with greater CBF velocity were less likely to have dementia. Furthermore, in nondemented subjects, greater CBF velocity was related to significantly less cognitive decline over the preceding period (odds ratio per standard deviation increase in mean CBF 0.74 [95% confidence interval, 0.58-0.98]) and larger hippocampal and amygdalar volumes. A low CBF is associated with dementia, but also with markers of incipient dementia. Although we cannot exclude that this is caused by preclinical neurodegeneration leading to hypoperfusion, it does suggest that cerebral hypoperfusion precedes and possibly contributes to onset of clinical dementia.
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Affiliation(s)
- Annemieke Ruitenberg
- Department of Epidemiology and Biostatistics, Erasmus Medical Center, Rotterdam, the Netherlands
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