OBJECTIVES: To investigate the efficacy of volume-guaranteed high-frequency oscillatory ventilation (HFOV-VG) in preterm infants with respiratory distress syndrome (RDS) and its impact on blood flow in the middle cerebral artery (MCA). METHODS: A prospective study was conducted on 120 preterm infants with RDS who were admitted to the Department of Neonatology at Qinhuangdao Maternal and Child Health Hospital from March 2020 to December 2023. According to the mode of ventilation, the infants were divided into two groups: a conventional mechanical ventilation (CMV) group (60 infants) and an HFOV-VG group (60 infants). The two groups were compared in terms of baseline data, MCA hemodynamic parameters, complications, and outcomes. RESULTS: Compared with the CMV group, the HFOV-VG group had significantly shorter durations of mechanical ventilation and hospital stay and a significantly higher overall response rate (P<0.05). The HFOV-VG group demonstrated significantly better peak systolic velocity, end-diastolic velocity, and mean flow velocity (P<0.05). The HFOV-VG group also exhibited significantly lower 28-day mortality rates and lower incidence rates of bronchopulmonary dysplasia and intraventricular hemorrhage than the CMV group (P<0.05). CONCLUSIONS HFOV-VG can effectively improve cerebral blood perfusion, reduce cerebrovascular resistance, shorten the durations of mechanical ventilation and hospital stay, and enhance overall treatment efficacy. It has significant advantages in reducing the risk of 28-day mortality, bronchopulmonary dysplasia, and intraventricular hemorrhage in preterm infants with RDS.
Humans ; High-Frequency Ventilation/adverse effects* ; Infant, Newborn ; Respiratory Distress Syndrome, Newborn/physiopathology* ; Female ; Middle Cerebral Artery/physiology* ; Male ; Prospective Studies ; Cerebrovascular Circulation ; Infant, Premature

OBJECTIVES: To explore the relationship between white matter injury (WMI) and cerebral perfusion in preterm infants using arterial spin labeling (ASL). METHODS: A total of 293 preterm infants (gestational age <34 weeks) hospitalized at the Third Affiliated Hospital of Zhengzhou University between June 2022 and June 2024 were included. After achieving clinical stability, the infants underwent brain magnetic resonance imaging (MRI) and ASL. Based on MRI findings, infants were classified into WMI (n=66) and non-WMI (n=227) groups. Cerebral perfusion parameters were compared between groups, and the association between WMI and perfusion alterations was evaluated. RESULTS: The WMI group showed a higher incidence of mild intraventricular hemorrhage (IVH) than the non-WMI group (P<0.05). Significantly lower cerebral perfusion was observed in the WMI group across bilateral frontal, temporal, parietal, and occipital lobes, as well as the basal ganglia and thalamus (P<0.05). After adjusting for gestational age, corrected gestational age at ASL scan, and mild IVH, WMI remained significantly associated with reduced regional perfusion (P<0.05). CONCLUSIONS WMI in preterm infants correlates with localized cerebral hypoperfusion. ASL-detected perfusion abnormalities may provide novel insights into WMI pathogenesis.
Humans ; White Matter/blood supply* ; Infant, Newborn ; Spin Labels ; Infant, Premature ; Female ; Male ; Cerebrovascular Circulation ; Magnetic Resonance Imaging

OBJECTIVE: To observe the dynamic changes of microvascular injury and repair in the penumbra of traumatic brain injury (TBI) rats with effective cerebral perfusion microvascular imaging using optical coherence tomography angiography (OCTA). METHODS: Transparent closed cranial windows were placed in craniotomy rats after TBI caused by weight drop. All the rats in TBI group and control group underwent head MRI examination on the first postoperative day, and the changes of cerebral cortical microvessel density were measured by OCTA through cranial windows on d0, d2, d4, d6, and d8. On the second day after the operation, the same number of rats in the two groups were selected to complete the immunohistochemical staining of brain tissue with pimonidazole, an indicator of hypoxia. RESULTS: MRI T2W1 and immunohistochemical staining demonstrated that edema and hypoxia in the traumatic brain tissue extended deeply throughout the entire cortex. OCTA showed that the cortical surface veins of the rats in both groups were significantly dilated and tortuous after operation, and recovered to the postoperative day level on d8. The effective perfusion microvessel density of the rats in both groups gradually recovered after a temporary decrease, and the TBI group decreased from 39.38%±4.48% on d0 to 27.84%±6.01% on d2, which was significantly lower than that on d0, d6, and d8 (P < 0.05). The highest value was 61.71%±7.69% on d8, which was significantly higher than that on d0, d2, and d4 (P < 0.05). The control group decreased from 44.59%±7.78% on d0 to 36.69%±5.49% on d2, which was significantly lower than that on d0, d6, and d8 (P < 0.05). The highest value was 51.92%±5.96% on d8, which was significantly higher than that on d2, and d4 (P < 0.05). Comparing the two groups, the effective perfusion microvessel density in the TBI group was significantly lower than that in the control group on d2 (P=0.021), and significantly higher than that in the control group on d8 (P=0.030). CONCLUSION OCTA can be used as a method of imaging and measurement of effective perfusion microvessels in the injured cerebral cortex of TBI rats. After TBI, the effective perfusion microvessel density in the wound penumbra gradually recovered after decreasing, and increased significantly on d8.
Animals ; Brain Injuries, Traumatic/physiopathology* ; Rats ; Tomography, Optical Coherence/methods* ; Male ; Rats, Sprague-Dawley ; Microvessels/pathology* ; Microvascular Density ; Cerebral Cortex/blood supply* ; Cerebrovascular Circulation

Hypotension is a leading cause of age-related cognitive impairment. The available literature evidences that vascular factors are associated with dementia and that hypotension alters cerebral perfusion flow and can aggravate the neurodegeneration of Alzheimer's disease (AD). Despite the discovery of biomarkers and the recent progress made in neurovascular biology, epidemiology, and brain imaging, some key issues remain largely unresolved: the potential mechanisms underlying the neural deterioration observed in AD, the effect of cerebrovascular alterations on cognitive deficits, and the positive effects of hypotension treatment on cognition. Therefore, further well-designed studies are needed to unravel the potential association between hypotension and cognitive dysfunction and reveal the potential benefits of hypotension treatment for AD patients. Here, we review the current epidemiological, pathobiological, and treatment-related literature on neurovascular changes and hypotension-related cognitive dysfunction and highlight the unsettled but imminent issues that warrant future research endeavors.
Humans ; Hypotension/complications* ; Cognitive Dysfunction/etiology* ; Alzheimer Disease/epidemiology* ; Cerebrovascular Circulation/physiology* ; Cognition Disorders/etiology*

Objective To investigate the alterations of cerebral blood flow(CBF)in type 2 diabetic mellitus(T2DM) patients without cognitive impairment by using arterial spin labeling(ASL)technique.Methods A total of 23 T2DM patients without cognitive impairment and 23 healthy controls(HC)matched by age,sex,and education attainment were recruited.Their clinical data were collected,and neuropsychological tests and cerebral magnetic resonance imaging were performed.Then,the outcomes of clinical features,neuropsychological tests,and global and regional CBF were compared between the two groups.The significant regional zCBF(z-transformed relative CBF)values were extracted and correlated with clinical data and neuropsychological scores in T2DM patients,controlling age,sex,and education.Results No significant difference was found in whole brain CBF between the two groups(P=0.155),while significantly higher CBF was identified in the left superior temporal gyrus and left insula in the T2DM group(Gaussian random field correction,initial threshold P < 0.001,cluster level P < 0.05).No correlation was observed between the significant regional zCBF values and the clinical data or the neuropsychological scores in T2DM patients(all P>0.05).Conclusion Alterations in cerebral hemodynamics may precede cognitive function changes in T2DM,suggesting that the ASL technique is promising for early monitoring of cerebral hemodynamic changes associated with cognitive impairment in patients with T2DM.
Humans ; Diabetes Mellitus, Type 2/physiopathology* ; Cerebrovascular Circulation ; Middle Aged ; Male ; Female ; Magnetic Resonance Imaging ; Case-Control Studies ; Cognitive Dysfunction ; Neuropsychological Tests ; Aged

Aging is a natural process accompanied with a progressive deterioration of cognitive functions. With an aging population, more and more elderly people are suffering from cognitive impairment. Previous studies have paid more attention to the impact of inflammation and oxidative stress on cognitive function during aging. Recently, it has been discovered that neurovascular coupling (NVC), a mechanism regulating cerebral blood flow, may play a significant role in aging-related cognitive impairment. NVC responses regulate the supply of energy substances and oxygen during brain activity, which in turn enhances cognitive function. However, as people grow older, NVC responses gradually weaken, which may be one of the mechanisms underlying aging-induced cognitive impairment. Given the important role of NVC responses in the brain, it is necessary to search for intervention methods that can improve NVC responses and promote cognitive function. Exercise is an effective means to delay aging and improve cognitive function. It also has a certain promoting effect on NVC responses. This article reviews the regulatory mechanisms of NVC responses, the relationship between NVC responses and cognitive function, and explores the effects of aging and exercise intervention on NVC responses, hoping to provide new research ideas for exercise intervention to improve NVC responses and promote cognitive function in the elderly.
Humans ; Aged ; Neurovascular Coupling/physiology* ; Aging ; Cerebrovascular Circulation/physiology* ; Cognition ; Brain

OBJECTIVES: To investigate local cerebral blood perfusion in preterm infants with bronchopulmonary dysplasia (BPD) based on cerebral blood flow (CBF) values of arterial spin labeling (ASL). METHODS: A prospective study was conducted on 90 preterm infants with a gestational age of <32 weeks and a birth weight of <1 500 g who were born in the Department of Obstetrics and admitted to the Department of Neonatology in the Third Affiliated Hospital of Zhengzhou University from August 2021 to June 2022. All of the infants underwent cranial MRI and ASL at the corrected gestational age of 35-40 weeks. According to the presence or absence of BPD, they were divided into a BPD group with 45 infants and a non-BPD group with 45 infants. The two groups were compared in terms of the CBF values of the same regions of interest (frontal lobe, temporal lobe, parietal lobe, occipital lobe, thalamus, and basal ganglia) on ASL image. RESULTS: Compared with the non-BPD group, the BPD group had a significantly lower 1-minute Apgar score, a significantly longer duration of assisted ventilation, and a significantly higher incidence rate of fetal distress (P<0.05). After control for the confounding factors such as corrected age and age at the time of cranial MRI by multiple linear regression analysis, compared with the non-BPD group, the BPD group still had higher CBF values of the frontal lobe, temporal lobe, parietal lobe, occipital lobe, basal ganglia, and thalamus at both sides (P<0.05). CONCLUSIONS BPD can increase cerebral blood perfusion in preterm infants, which might be associated with hypoxia and a long duration of assisted ventilation in the early stage.
Infant ; Pregnancy ; Female ; Infant, Newborn ; Humans ; Infant, Premature ; Bronchopulmonary Dysplasia/epidemiology* ; Prospective Studies ; Gestational Age ; Cerebrovascular Circulation

BACKGROUND: Insufficient cerebral perfusion is suggested to play a role in the development of Alzheimer disease (AD). However, there is a lack of direct evidence indicating whether hypoperfusion causes or aggravates AD pathology. We investigated the effect of chronic cerebral hypoperfusion on AD-related pathology in humans. METHODS: We enrolled a group of cognitively normal patients (median age: 64 years) with unilateral chronic cerebral hypoperfusion. Regions of interest with the most pronounced hypoperfusion changes were chosen in the hypoperfused region and were then mirrored in the contralateral hemisphere to create a control region with normal perfusion. 11C-Pittsburgh compound-positron emission tomography standard uptake ratios and brain atrophy indices were calculated from the computed tomography images of each patient. RESULTS: The median age of the 10 participants, consisting of 4 males and 6 females, was 64 years (47-76 years). We found that there were no differences in standard uptake ratios of the cortex (volume of interest [VOI]: P = 0.721, region of interest [ROI]: P = 0.241) and grey/white ratio (VOI: P = 0.333, ROI: P = 0.445) and brain atrophy indices (Bicaudate, Bifrontal, Evans, Cella, Cella media, and Ventricular index, P > 0.05) between the hypoperfused regions and contralateral normally perfused regions in patients with unilateral chronic cerebral hypoperfusion. CONCLUSION Our findings suggest that chronic hypoperfusion due to large vessel stenosis may not directly induce cerebral β-amyloid deposition and neurodegeneration in humans.
Aged ; Alzheimer Disease/pathology* ; Amyloid beta-Peptides/metabolism* ; Arteries ; Atrophy ; Brain/metabolism* ; Cerebral Cortex/metabolism* ; Cerebrovascular Circulation ; Constriction, Pathologic/pathology* ; Female ; Humans ; Magnetic Resonance Imaging/methods* ; Male ; Middle Aged ; Positron-Emission Tomography/methods*

By using Doppler sensor and pressure sensor, the cerebrovascular stroke detector can be used to measure the blood flow velocity and blood pressure of the carotid artery. In this study, a variety of signal conversion and isolation processing techniques are proposed for processing and feature extraction of the output signals from the sensors. Finally, effective signal output waveforms that can be used to evaluate the cerebrovascular hemodynamics index (CVHI) are obtained, and the sound signal outputs that can reflect the change characteristics of blood flow velocity and blood pressure signals are generated, which realizes the application functional requirements of the detector.
Blood Flow Velocity/physiology* ; Cerebrovascular Circulation/physiology* ; Hemodynamics/physiology* ; Humans ; Stroke ; Technology

OBJECTIVES: The patients with mild traumatic brain injury (mTBI) accounts for more than 80% of the patients with brain injury. Most patients with mTBI have no abnormalities in CT examination. Therefore, most patients choose to self-care and recover rather than seeking medical treatment. In fact, mTBI may result in persistent cognitive decline and neurobehavioral dysfunction. In addition, changes occurred in neurochemistry, metabolism, and cells after injury may cause changes in cerebral blood flow (CBF), which is one of the causes of secondary injury and slow brain repair. This study aims to evaluate the changes of CBF with the progression of the disease in patients with mTBI based on arterial spin labeling (ASL) magnetic resonance imaging technology. METHODS: In the outpatient or emergency department of the Second Affiliated Hospital of Wenzhou Medical University, 43 mTBI patients were collected as an mTBI group, and 43 normal subjects with age, gender, and education level matching served as a control group. They all received clinical neuropsychology and cognitive function evaluation and magnetic resonance imaging. In the mTBI group, 22 subjects were followed up at acute phase, 1 month, 3 months, and 12 months. Based on the control group, the abnormal regions of CBF in the whole brain of mTBI patients were analyzed. The abnormal regions were taken as the regions of interest (ROI). The correlation of the values of the CBF in ROIs with clinical indications, cognitive function, and the changes of CBF in ROI at each time point during the follow-up were analyzed. RESULTS: Compared with the control group, the CBF in the bilateral dorsolateral superior frontal gyrus and auxiliary motor areas in the cortical region, as well as the right putamen, caudate nucleus, globus pallidus, and parahippocampus in the subcutaneous regions in the acute phase of the mTBI group were significantly increased (all P<0.01, TFCE-FWE correction). The analysis results of correlation of CBF with neuropsychology and cognitive domain showed that in the mTBI group, whole brain (r=0.528, P<0.001), right caudate nucleus (r=0.512, P<0.001), putamen (r=0.486, P<0.001), and globus pallidus (r=0.426, P=0.006) values of the were positively correlated with Backward Digit Span Test (BDST) score (reflectting working memory ability), and the right globus pallidus CBF was negatively correlated with the Post-Traumatic Stress Disorder Cheeklist-CivilianVersion (PCL-C) score (r=-0.402, P=0.010). Moreover, the follow-up study showed that abnormal CBF in these areas had not been restored. The correlation of CBF was negatively correlated with PCL-C and BDST at 1 months, 3 months, and 12 months (all P>0.05). CONCLUSIONS The elevated CBF value is one of the stress characteristics of brain injury in the mTBI patients at the acute phase. There is abnormal elevation of CBF values in multiple cortex or subcortical areas. Multi-time point studies show that there is no obvious change of CBF in abnormal areas, suggesting that potential clinical treatment is urgently needed for the mTBI patients.
Brain Concussion/diagnostic imaging* ; Brain Injuries ; Cerebrovascular Circulation/physiology* ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging/methods* ; Magnetic Resonance Spectroscopy ; Spin Labels