Effect of Phlebotomy on Cerebral Blood Flow and Function

2015 ◽  
pp. 139-144
Author(s):  
D. J. Thomas ◽  
J. R. Willison
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
And Function

scholarly journals Accelerated brain aging and cerebral blood flow reduction in persons with HIV

2021 ◽  
Author(s):  
Kalen J Petersen ◽  
Nicholas Metcalf ◽  
Sarah Cooley ◽  
Dimitre Tomov ◽  
Florin Vaida ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Aging ◽  
Learning Algorithm ◽  
Psychomotor Speed ◽  
Deep Learning Algorithm ◽  
Blood Flow Reduction ◽  
Brain Structure And Function ◽  
N 93 ◽  
And Function

Abstract Background Persons with HIV (PWH) are characterized by altered brain structure and function. As they attain normal lifespans, it has become crucial to understand potential interactions between HIV and aging. However, it remains unclear how brain aging varies with viral load (VL). Methods In this study, we compare MRI biomarkers amongst PWH with undetectable VL (UVL; ≤50 genomic copies/ml; n=230), PWH with detectable VL (DVL; >50 copies/ml; n=93), and HIV uninfected (HIV-) controls (n=206). To quantify gray matter cerebral blood flow (CBF), we utilized arterial spin labeling. To measure structural aging, we used a publicly available deep learning algorithm to estimate brain age from T1-weighted MRI. Cognitive performance was measured using a neuropsychological battery covering five domains. Results Associations between age and CBF varied with VL. Older PWH with DVL had reduced CBF vs. PWH with UVL (p=0.02). Structurally predicted brain aging was accelerated in PWH vs. HIV- controls regardless of VL (p<0.001). Overall, PWH had impaired learning, executive function, psychomotor speed, and language compared to HIV- controls. Structural brain aging was associated with reduced psychomotor speed (p<0.001). Conclusions Brain aging in HIV is multifaceted. CBF depends on age and current VL, and is improved by medication adherence. By contrast, structural aging is an indicator of cognitive function and reflects serostatus rather than current VL.

scholarly journals Noninvasive Optical Monitoring of Cerebral Blood Flow and EEG Spectral Responses after Severe Traumatic Brain Injury: A Case Report

2021 ◽  
Vol 11 (8) ◽  
pp. 1093
Author(s):  
Chien-Sing Poon ◽  
Benjamin Rinehart ◽  
Dharminder S. Langri ◽  
Timothy M. Rambo ◽  
Aaron J. Miller ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Injury ◽  
Brain Activity ◽  
Correlation Spectroscopy ◽  
Secondary Brain Injury ◽  
Diffuse Correlation Spectroscopy ◽  
Flow Monitoring ◽  
And Function

Survivors of severe brain injury may require care in a neurointensive care unit (neuro-ICU), where the brain is vulnerable to secondary brain injury. Thus, there is a need for noninvasive, bedside, continuous cerebral blood flow monitoring approaches in the neuro-ICU. Our goal is to address this need through combined measurements of EEG and functional optical spectroscopy (EEG-Optical) instrumentation and analysis to provide a complementary fusion of data about brain activity and function. We utilized the diffuse correlation spectroscopy method for assessing cerebral blood flow at the neuro-ICU in a patient with traumatic brain injury. The present case demonstrates the feasibility of continuous recording of noninvasive cerebral blood flow transients that correlated well with the gold-standard invasive measurements and with the frequency content changes in the EEG data.

The dissociation of cerebral blood flow, metabolism, and function in the early stages of developing cerebral infarction

1980 ◽  
Vol 8 (3) ◽  
pp. 278-290 ◽  
Author(s):  
K. Kogure ◽  
R. Busto ◽  
R. J. Schwartzman ◽  
P. Scheinberg
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Cerebral Infarction ◽  
Early Stages ◽  
And Function

scholarly journals Cerebral arteriolar structure and function in pinealectomized rats

2001 ◽  
Vol 281 (4) ◽  
pp. H1476-H1480 ◽  
Author(s):  
Olivier Régrigny ◽  
François Dupuis ◽  
Jeffrey Atkinson ◽  
Patrick Limiñana ◽  
Elizabeth Scalbert ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Wistar Rats ◽  
Structure And Function ◽  
Internal Diameter ◽  
Sectional Area ◽  
Cross Sectional ◽  
Cranial Window ◽  
Arteriolar Wall ◽  
And Function

We examined cerebral arteriolar structure and autoregulation of cerebral blood flow (CBF) in control ( n = 8), sham-operated ( n = 8), pinealectomized ( n = 10), and pinealectomized plus melatonin-treated (0.51 ± 0.01 mg · kg−1 · day−1 in drinking water, n = 9) young Wistar rats. The lower limit of CBF autoregulation (LLCBF) was determined by measurement of CBF (in arbitrary units, laser Doppler) during stepwise hypotensive hemorrhage; the arteriolar internal diameter (ID; in μm, cranial window) was also measured. Measurements of ID were repeated during a second stepwise hypotension after smooth muscle cell deactivation (67 mmol/l EDTA). The cross-sectional area (CSA) was measured by histometry. CSA and EDTA-induced vasodilatation decreased after pinealectomy (517 ± 21 vs. 819 ± 40 μm2 in sham and 829 ± 55 μm2 in control, P < 0.05, and 81 ± 4 vs. 102 ± 5 μm in sham and 104 ± 4 μm in control, P < 0.05, respectively) and were restored by melatonin (924 ± 39 μm2 and 102 ± 5 μm, respectively). These results suggest that melatonin deprival makes the arteriolar wall thinner and stiffer. However, these changes had little effect on LLCBF. In conclusion, pinealectomy of young rats induces atrophy and decreases distensibility of the cerebral arteriolar wall; these effects are prevented by melatonin. They do not modify LLCBF.

scholarly journals Regular walking breaks prevent the decline in cerebral blood flow associated with prolonged sitting

2018 ◽  
Vol 125 (3) ◽  
pp. 790-798 ◽  
Author(s):  
Sophie E. Carter ◽  
Richard Draijer ◽  
Sophie M. Holder ◽  
Louise Brown ◽  
Dick H. J. Thijssen ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Carotid Artery ◽  
Light Intensity ◽  
Short Duration ◽  
Sitting Time ◽  
Peripheral Blood Flow ◽  
Prolonged Sitting ◽  
Increased Risk ◽  
And Function

Decreased cerebrovascular blood flow and function are associated with lower cognitive functioning and increased risk of neurodegenerative diseases. Prolonged sitting impairs peripheral blood flow and function, but its effects on the cerebrovasculature are unknown. This study explored the effect of uninterrupted sitting and breaking up sitting time on cerebrovascular blood flow and function of healthy desk workers. Fifteen participants (10 male, 35.8 ± 10.2 yr, body mass index: 25.5 ± 3.2 kg/m2) completed, on separate days, three 4-h conditions in a randomized order: 1) uninterrupted sitting (SIT), 2) sitting with 2-min light-intensity walking breaks every 30 min (2WALK), or 3) sitting with 8-min light-intensity walking breaks every 2 h (8WALK). At baseline and 4 h, middle cerebral artery blood flow velocity (MCAv) and CO2 reactivity (CVR) of the MCA and carotid artery were measured using transcranial Doppler (TCD) and duplex ultrasound, respectively. Cerebral autoregulation (CA) was assessed with TCD using a squat-stand protocol and analyzed to generate values of gain and phase in the very low, low, and high frequencies. There was a significant decline in SIT MCAv (−3.2 ± 1.2 cm/s) compared with 2WALK (0.6 ± 1.5 cm/s, P = 0.02) but not between SIT and 8WALK (−1.2 ± 1.0 cm/s, P = 0.14). For CA, the change in 2WALK very low frequency phase (4.47 ± 4.07 degrees) was significantly greater than SIT (−3.38 ± 2.82 degrees, P = 0.02). There was no significant change in MCA or carotid artery CVR ( P > 0.05). Results indicate that prolonged uninterrupted sitting in healthy desk workers reduces cerebral blood flow; however, this is offset when frequent short-duration walking breaks are incorporated. NEW & NOTEWORTHY Prolonged uninterrupted sitting in healthy desk workers reduces cerebral blood flow. However, this reduction in cerebral blood flow is offset when frequent short-duration walking breaks are incorporated into this sitting period. For those who engage in long periods of sedentary behavior, chronically breaking up these sitting periods with frequent active break strategies may have important implications for cerebrovascular health; however, further research should explore this hypothesis.

scholarly journals Noninvasive Optical Monitoring of Cerebral Blood Flow and EEG Spectral Responses after Severe Traumatic Brain Injury: A Case Report

2021 ◽  
Author(s):  
Chien-Sing Poon ◽  
Benjamin Rinehart ◽  
Dharminder S. Langri ◽  
Timothy M. Rambo ◽  
Aaron J. Miller ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Injury ◽  
Brain Activity ◽  
Clinical Care ◽  
Secondary Brain Injury ◽  
Flow Monitoring ◽  
Eeg Data ◽  
And Function

Survivors of severe brain injury may require care in a neurointensive care unit (neuro-ICU), where the brain is vulnerable to secondary brain injury. Thus, there is a need for noninvasive, bedside, continuous cerebral blood flow monitoring approaches in the neuro-ICU. Our goal is to address this need through combined measurements of EEG and functional optical spectroscopy (EEG-Optical) instrumentation and analysis to provide a complementary fusion of data about brain activity and function. The present case demonstrates in a patient with traumatic brain injury, noninvasive cerebral blood flow transients can be recorded that correlate with gold-standard invasive measurements and with the frequency content changes in the EEG data during clinical care.

scholarly journals Noninvasive optical monitoring of cerebral blood flow and EEG Spectral responses after Severe Traumatic Brain Injury: A Case Report

2021 ◽  
Author(s):  
Chien-Sing Poon ◽  
Benjamin Rinehart ◽  
Dharminder S Langri ◽  
Timothy M Rambo ◽  
Aaron J Miller ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Injury ◽  
Brain Activity ◽  
Correlation Spectroscopy ◽  
Secondary Brain Injury ◽  
Diffuse Correlation Spectroscopy ◽  
Flow Monitoring ◽  
And Function

Survivors of severe brain injury may require care in a neurointensive care unit (neuro-ICU), where the brain is vulnerable to secondary brain injury. Thus, there is a need for noninvasive, bedside, continuous cerebral blood flow monitoring approaches in the neuro-ICU. Our goal is to address this need through combined measurements of EEG and functional optical spectroscopy (EEG-Optical) instrumentation and analysis to provide a complementary fusion of data about brain activity and function. We utilized diffuse correlation spectroscopy method for assessing cerebral blood flow at neuro-ICU in a patient with traumatic brain injury. The present case demonstrates the feasibility of continuous recording of noninvasive cerebral blood flow transients that correlated well with the gold-standard invasive measurements and with the frequency content changes in the EEG data.

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