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Claessens PJ, Peeters R, Claessens L, Claessens C, Claessens J, Claessens PM. Pulse wave analysis measurements: important, underestimated and undervalued parameters in cardiovascular health problems. Front Cardiovasc Med 2023; 10:1266258. [PMID: 38028442 PMCID: PMC10653328 DOI: 10.3389/fcvm.2023.1266258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 09/25/2023] [Indexed: 12/01/2023] Open
Abstract
Background Central aortic stiffness is established as a reliable measure of cardiovascular disease. While pulse wave velocity (PWV) analysis measures arterial distensibility, risk profile of cardiovascular diseases can be expanded with following pulse wave analysis measurements: central aortic systolic blood pressure (CABPS), central aortic pulse pressure (CAPP), central aortic reflection magnitude (CARM), central aortic augmented pressure (CAAP) and central aortic augmentation index (CAAIx). The aim of this study is to evaluate the clinical usefulness and importance of pulse wave analysis measurements in specific cardiovascular conditions and diseases, both in term of diagnosis and therapeutic monitoring. Methods One thousand sixty-six subjects were included. According to age bracket, four cohorts were investigated-healthy subjects (NL), hypertensive patients (HP), ischemic heart disease (IHD) and valvular heart disease (VHD) patients. Arterial stiffness was analyzed through Sphygmocor XCEL Central Blood Pressure Measurement System and Sphygmocor XCEL PWV Measurement System. Furthermore we observed the pulse wave analysis measurements of 14 patients with diagnose of ADHD who were referred by a child psychiatrist, in order to investigate the initiation of methylphenidate treatment. Results Statistically significant differences were found between NL and HP cohorts, across almost all age brackets, regarding pulse wave analysis measurements. In the risk stratification of arterial stiffness hypertension and especially central aortic blood pressure systolic (CABPS) seems a determining factor. Pulse wave analysis measurements for IHD and VHD cohort comparisons with NL counterparts, revealed non- statistically significant variations. Elevated CAAP, CAAIx and CARM within the youngest age group (0-10 years) in attention-deficit-hyperactivity-disorder (ADHD) patients warrant attention. Conclusions Following such investigations, CABPS appears as a robust predominant factor in problems of arterial stiffness. Pulse wave analysis and PWV are important parameters in the evaluation and monitoring of arterial hypertension and cardiovascular diseases. There is a hypothesis that CAAP could be an important and even decisive parameter in the diagnosis of ADHD. Further investigation needed.
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Affiliation(s)
| | | | | | | | | | - Philip Maria Claessens
- Medical Center “Kloppend Hart Essen-Antwerpen- Schilde”, Antwerp, Belgium
- Department of Cardiology, AZ Monica Deurne, Antwerp, Belgium
- Department of Cardiology, AZ Voorkempen Malle, Antwerp, Belgium
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Daniel JM, Lindsey SH, Mostany R, Schrader LA, Zsombok A. Cardiometabolic health, menopausal estrogen therapy and the brain: How effects of estrogens diverge in healthy and unhealthy preclinical models of aging. Front Neuroendocrinol 2023; 70:101068. [PMID: 37061205 PMCID: PMC10725785 DOI: 10.1016/j.yfrne.2023.101068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/23/2023] [Accepted: 04/10/2023] [Indexed: 04/17/2023]
Abstract
Research in preclinical models indicates that estrogens are neuroprotective and positively impact cognitive aging. However, clinical data are equivocal as to the benefits of menopausal estrogen therapy to the brain and cognition. Pre-existing cardiometabolic disease may modulate mechanisms by which estrogens act, potentially reducing or reversing protections they provide against cognitive decline. In the current review we propose mechanisms by which cardiometabolic disease may alter estrogen effects, including both alterations in actions directly on brain memory systems and actions on cardiometabolic systems, which in turn impact brain memory systems. Consideration of mechanisms by which estrogen administration can exert differential effects dependent upon health phenotype is consistent with the move towards precision or personalized medicine, which aims to determine which treatment interventions will work for which individuals. Understanding effects of estrogens in both healthy and unhealthy models of aging is critical to optimizing the translational link between preclinical and clinical research.
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Affiliation(s)
- Jill M Daniel
- Department of Psychology and Brain Institute, Tulane University, New Orleans, LA, United States.
| | - Sarah H Lindsey
- Department of Pharmacology and Brain Institute, Tulane University, New Orleans, LA, United States
| | - Ricardo Mostany
- Department of Pharmacology and Brain Institute, Tulane University, New Orleans, LA, United States
| | - Laura A Schrader
- Department of Cell & Molecular Biology and Brain Institute, Tulane University, New Orleans, LA, United States
| | - Andrea Zsombok
- Department of Physiology and Brain Institute, Tulane University, New Orleans, LA, United States
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Qvarlander S, Dombrowski SM, Biswas D, Thyagaraj S, Loth F, Yang J, Luciano MG. Modifying the ICP pulse wave: effects on parenchymal blood flow pulsatility. J Appl Physiol (1985) 2023; 134:242-252. [PMID: 36548513 PMCID: PMC9886344 DOI: 10.1152/japplphysiol.00401.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 12/07/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Abstract
Pulsation of the cerebral blood flow (CBF) produces intercranial pressure (ICP) waves. The aim of this study is to determine whether externally modifying ICP pulsatility alters parenchymal blood flow pulsatility. A cardiac-gated inflatable device was inserted in the lateral epidural space of 12 anesthetized canines (canis familiaris) and used to cause reduction, inversion, and augmentation of the ICP pulse. CBF in each hemisphere was measured using laser Doppler velocimetry. A significant increase in both mean CBF and its amplitude was observed for reduction as well as inversion of the ICP pulse, with larger changes observed for the inversion protocol. Significant increases in the mean CBF were also observed ipsilaterally for the augmentation protocol together with indications of reduced CBF amplitude contralaterally. External alteration of the ICP pulse thus caused significant changes in parenchymal blood flow pulsatility. The inverse relationship between the ICP and CBF amplitude suggests that the changes did not occur via modification of the intracranial Windkessel mechanism. Thus, the effects likely occurred in the low-pressure vessels, i.e., capillaries and/or venules, rather than the high-pressure arteries. Future MRI studies are however required to map and quantify the effects on global cerebral blood flow.NEW & NOTEWORTHY This study demonstrated that external modification of ICP pulsatility, using a cardiac-gated inflatable device implanted epidurally in canines, alters brain tissue blood flow pulsatility. Specifically, decreasing systolic ICP increased blood flow pulsatility in brain tissue. The results suggest that the altered CBF pulsatility is unlikely to depend on modification of the Windkessel effect on the feeding arterial system but was rather an effect directly on tissue and the lower pressure distal vessels.
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Affiliation(s)
- Sara Qvarlander
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, Umeå University, Umeå, Sweden
- Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, Ohio
| | | | - Dipankar Biswas
- Department of Neurosurgery, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Suraj Thyagaraj
- Department of Biomedical Engineering, School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Francis Loth
- Department of Mechanical and Industrial Engineering and Department of Bioengineering, Northeastern University, Boston, Massachusetts
| | - Jun Yang
- Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, Ohio
- Department of Neurosurgery, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, People's Republic of China
| | - Mark G Luciano
- Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, Ohio
- Department of Neurosurgery, Johns Hopkins Medical Institutions, Baltimore, Maryland
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Varga BT, Gáspár A, Ernyey AJ, Hutka B, Tajti BT, Zádori ZS, Gyertyán I. Introduction of a pharmacological neurovascular uncoupling model in rats based on results of mice. Physiol Int 2022. [PMID: 36057105 DOI: 10.1556/2060.2022.00226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 05/02/2022] [Accepted: 05/19/2022] [Indexed: 02/18/2024]
Abstract
Our aim was to establish a pharmacologically induced neurovascular uncoupling (NVU) method in rats as a model of human cognitive decline. Pharmacologically induced NVU with subsequent neurological and cognitive defects was described in mice, but not in rats so far. We used 32 male Hannover Wistar rats. NVU was induced by intraperitoneal administration of a pharmacological "cocktail" consisting of N-(methylsulfonyl)-2-(2-propynyloxy)-benzenehexanamide (MSPPOH, a specific inhibitor of epoxyeicosatrienoic acid-producing epoxidases, 5 mg kg-1), L-NG-nitroarginine methyl ester (L-NAME, a nitric oxide synthase inhibitor, 10 mg kg-1) and indomethacin (a nonselective inhibitor of cyclooxygenases, 1 mg kg-1) and injected twice daily for 8 consecutive days. Cognitive performance was tested in the Morris water-maze and fear-conditioning assays. We also monitored blood pressure. In a terminal operation a laser Doppler probe was used to detect changes in blood-flow (CBF) in the barrel cortex while the contralateral whisker pad was stimulated. Brain and small intestine tissue samples were collected post mortem and examined for prostaglandin E2 (PGE2) level. Animals treated with the "cocktail" showed no impairment in their performance in any of the cognitive tasks. They had higher blood pressure and showed cca. 50% decrease in CBF. Intestinal bleeding and ulcers were found in some animals with significantly decreased levels of PGE2 in the brain and small intestine. Although we could evoke NVU by the applied mixture of pharmacons, it also induced adverse side effects such as hypertension and intestinal malformations while the treatment did not cause cognitive impairment. Thus, further refinements are still required for the development of an applicable model.
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Affiliation(s)
- Bence Tamás Varga
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Attila Gáspár
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Aliz Judit Ernyey
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Barbara Hutka
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Brigitta Tekla Tajti
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Zoltán Sándor Zádori
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - István Gyertyán
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
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Heal M, McFall GP, Vergote D, Jhamandas JH, Westaway D, Dixon RA. Bridging Integrator 1 (BIN1, rs6733839) and Sex Are Moderators of Vascular Health Predictions of Memory Aging Trajectories. J Alzheimers Dis 2022; 89:265-281. [DOI: 10.3233/jad-220334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background: A promising risk loci for sporadic Alzheimer’s disease (AD), Bridging Integrator 1 (BIN1), is thought to operate through the tau pathology pathway. Objective: We examine BIN1 risk for a moderating role with vascular health (pulse pressure; PP) and sex in predictions of episodic memory trajectories in asymptomatic aging adults. Methods: The sample included 623 participants (Baseline Mean age = 70.1; 66.8% female) covering a 44-year longitudinal band (53–97 years). With an established memory latent variable arrayed as individualized trajectories, we applied Mplus 8.5 to determine the best fitting longitudinal growth model. Main analyses were conducted in three sequential phases to investigate: 1) memory trajectory prediction by PP, 2) moderation by BIN1 genetic risk, and 3) stratification by sex. Results: We first confirmed that good vascular health (lower PP) was associated with higher memory level and shallower decline and males were more severely affected by worsening PP in both memory performance and longitudinal decline. Second, the PP prediction of memory trajectories was significant for BIN1 C/C and C/T carriers but not for persons with the highest AD risk (T/T homozygotes). Third, when further stratified by sex, the BIN1 moderation of memory prediction by PP was selective for females. Conclusion: We observed a novel interaction whereby BIN1 (linked with tauopathy in AD) and sex sequentially moderated a benchmark PP prediction of differential memory decline in asymptomatic aging. This multi-modal biomarker interaction approach, disaggregated by sex, can be an effective method for enhancing precision of AD genetic risk assessment.
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Affiliation(s)
- Mackenzie Heal
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - G. Peggy McFall
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
| | - David Vergote
- Faculté Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Jack H. Jhamandas
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Department of Medicine (Neurology), University of Alberta, Edmonton, Alberta, Canada
| | - David Westaway
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Roger A. Dixon
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
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Lamar M, Fleischman DA, Leurgans SE, Aggarwal N, Yu L, Kim N, Poole V, Han SD, Arfanakis K, Barnes LL. Relationship of Blood Pressure and White Matter Hyperintensity Burden With Level of and Change in Cognition in Older Black Adults. Psychosom Med 2022; 84:437-445. [PMID: 35100182 PMCID: PMC9064910 DOI: 10.1097/psy.0000000000001059] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Elevations in blood pressure (BP) and associated white matter hyperintensities (WMHs) are chronic comorbid conditions among older Black adults. We investigated whether WMHs modify the association between late-life BP and cognition within older Black adults. METHODS A total of 167 Black adults (age, ~75 years; without dementia at baseline) participating in neuroimaging studies at the Rush Alzheimer's Disease Center were evaluated for BP markers of cardiovascular health, including systolic BP, diastolic BP, pulse pressure, mean arterial pressure (MAP), and hypertension, and were assessed for global and domain-specific cognition at baseline and annually for up to 8 years. WMHs adjusted for intracranial volume were quantified at baseline. RESULTS Models adjusted for relevant confounders and the interaction of these variables with time revealed differential associations between BP markers and baseline cognition; however, only elevated diastolic BP predicted faster cognitive, that is, episodic memory, decline (estimate = -0.002, standard error = 0.0009, p = .002). Although WMH burden did not modify the association between diastolic BP and episodic memory decline, it did interact with diastolic BP to lower episodic memory at baseline (estimate = -0.051, standard error = 0.012, p = .0001); that is, greater WMHs combined with higher diastolic BP resulted in the lowest baseline episodic memory scores. A similar profile was noted for WMHs, MAP, and baseline episodic memory. Hypertension was neither associated with cognition nor modified by WMH burden after multiple comparisons correction. CONCLUSION Late-life diastolic BP was associated with faster rates of episodic memory decline in older Black adults; together with higher WMH burden, it (and MAP) lowered the point at which individuals begin their course of decline toward pathological aging.
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Affiliation(s)
- Melissa Lamar
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Debra A. Fleischman
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Sue E. Leurgans
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Neelum Aggarwal
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Lei Yu
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Namhee Kim
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Victoria Poole
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, USA
| | - S. Duke Han
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Departments of Family Medicine and Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Department of Psychology, University of Southern California, Los Angeles, CA, USA
- School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Konstantinos Arfanakis
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA
- Department of Diagnostic Radiology and Nuclear Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Lisa L. Barnes
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
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Fernández-Jiménez R, Real C. Optimizing Blood Pressure Components for a Healthy Brain: The Holy Grail in Blood Pressure Management. J Am Coll Cardiol 2022; 79:1336-1339. [PMID: 35393013 DOI: 10.1016/j.jacc.2022.01.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/15/2022]
Affiliation(s)
- Rodrigo Fernández-Jiménez
- Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain; Hospital Universitario Clínico San Carlos, Madrid, Spain; Centro de Investigación Biomédica en Red en Enfermedades CardioVasculares, Madrid, Spain.
| | - Carlos Real
- Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain; Hospital Universitario Clínico San Carlos, Madrid, Spain. https://twitter.com/carlosreal42
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Diomedi M, Rocco A, Bonomi CG, Mascolo AP, De Lucia V, Marrama F, Sallustio F, Koch G, Martorana A. Haemodynamic impairment along the Alzheimer's disease continuum. Eur J Neurol 2021; 28:2168-2173. [PMID: 33759296 DOI: 10.1111/ene.14834] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND PURPOSE Alzheimer's disease (AD) is considered a clinical and biological continuum identified via cerebrospinal fluid (CSF) or imaging biomarkers. Chronic hypoperfusion is held as one of the main features of Alzheimer's disease, as part of the processes causing neuronal degeneration. The mechanism responsible for such condition is still debated, although recently a direct connection with amyloid peptides has been shown. Here the aim was to investigate whether measures of hypoperfusion change along the AD continuum. METHODS Seventy patients with mild AD were recruited and stratified according to their CSF biomarker profile-as indicated by the National Institute on Aging and Alzheimer's Association research framework-into patients with either isolated amyloid pathology (A+T-) or full-blown AD (A+T+), and further layered according to apolipoprotein E genotype. After evaluation of vascular risk factors, a transcranial Doppler was performed on each patient, to evaluate mean flow velocity and pulsatility index in the middle cerebral artery, and to calculate the breath-holding index. Patients were compared to a cohort of 17 healthy controls. RESULTS The breath-holding index was reduced in the AD continuum and was inversely correlated to CSF amyloid β42 levels. Such correlation was stronger in the A+T+ than in the A+T- group, and unexpectedly reached statistical significance only in the E3 and not in the E4 genotype carriers. CONCLUSIONS These results suggest a tight and effective relationship between amyloid β42, vascular hypoperfusion, cerebrovascular reactivity and epsilon genotype.
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Affiliation(s)
- Marina Diomedi
- Stroke Center, Policlinico Tor Vergata, Rome University 'Tor Vergata', Rome, Italy
| | - Alessandro Rocco
- Stroke Center, Policlinico Tor Vergata, Rome University 'Tor Vergata', Rome, Italy
| | | | | | - Vincenzo De Lucia
- Memory Clinic, Policlinico Tor Vergata, Rome University 'Tor Vergata', Rome, Italy
| | - Federico Marrama
- Stroke Center, Policlinico Tor Vergata, Rome University 'Tor Vergata', Rome, Italy
| | - Fabrizio Sallustio
- Stroke Center, Policlinico Tor Vergata, Rome University 'Tor Vergata', Rome, Italy
| | - Giacomo Koch
- Non Invasive Brain Stimulation Unit, IRCCS Santa Lucia, Rome, Italy.,Dipartimento di Neuroscienze e Riabilitazione, Sezione di Fisiologia Umana, Università di Ferrara, Ferrara, Italy
| | - Alessandro Martorana
- Memory Clinic, Policlinico Tor Vergata, Rome University 'Tor Vergata', Rome, Italy
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Ultrasonic Assessment of the Medial Temporal Lobe Tissue Displacements in Alzheimer’s Disease. Diagnostics (Basel) 2020; 10:diagnostics10070452. [PMID: 32635379 PMCID: PMC7399840 DOI: 10.3390/diagnostics10070452] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 06/30/2020] [Accepted: 07/01/2020] [Indexed: 12/31/2022] Open
Abstract
We aim to estimate brain tissue displacements in the medial temporal lobe (MTL) using backscattered ultrasound radiofrequency (US RF) signals, and to assess the diagnostic ability of brain tissue displacement parameters for the differentiation of patients with Alzheimer’s disease (AD) from healthy controls (HC). Standard neuropsychological evaluation and transcranial sonography (TCS) for endogenous brain tissue motion data collection are performed for 20 patients with AD and for 20 age- and sex-matched HC in a prospective manner. Essential modifications of our previous method in US waveform parametrization, raising the confidence of micrometer-range displacement signals in the presence of noise, are done. Four logistic regression models are constructed, and receiver operating characteristic (ROC) curve analyses are applied. All models have cut-offs from 61.0 to 68.5% and separate AD patients from HC with a sensitivity of 89.5% and a specificity of 100%. The area under a ROC curve of predicted probability in all models is excellent (from 95.2 to 95.7%). According to our models, AD patients can be differentiated from HC by a sharper morphology of some individual MTL spatial point displacements (i.e., by spreading the spectrum of displacements to the high-end frequencies with higher variability across spatial points within a region), by lower displacement amplitude differences between adjacent spatial points (i.e., lower strain), and by a higher interaction of these attributes.
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