The Utility of Cerebral Blood Flow Assessment in TBI

Akbik, Omar S.; Carlson, Andrew P.; Krasberg, Mark; Yonas, Howard

doi:10.1007/s11910-016-0672-3

Cited by 18 publications

(9 citation statements)

References 103 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[24][25][26] Alterations in cerebral blood flow (CBF) post-TBI are common, and optimization of CBF has been used as a therapeutic target, particularly in severe TBI. [26][27][28][29] In addition to these acute disruptions, alterations in blood flow and blood vessel function persist long after injury. 30 Cerebral vascular reactivity (CVR), a measure of blood vessel dilation in response to a vasoactive stimulus, is impaired post-TBI.…”

Section: Introductionmentioning

confidence: 99%

Vascular Abnormalities within Normal Appearing Tissue in Chronic Traumatic Brain Injury

Haber

Amyot

Kenney

et al. 2018

Journal of Neurotrauma

View full text Add to dashboard Cite

Magnetic resonance imaging (MRI) is a powerful tool for visualizing traumatic brain injury(TBI)-related lesions. Trauma-induced encephalomalacia is frequently identified by its hyperintense appearance on fluid-attenuated inversion recovery (FLAIR) sequences. In addition to parenchymal lesions, TBI commonly results in cerebral microvascular injury, but its anatomical relationship to parenchymal encephalomalacia is not well characterized. The current study utilized a multi-modal MRI protocol to assess microstructural tissue integrity (by mean diffusivity [MD] and fractional aniosotropy [FA]) and altered vascular function (by cerebral blood flow [CBF] and cerebral vascular reactivity [CVR]) within regions of visible encephalomalacia and normal appearing tissue in 27 chronic TBI (minimum 6 months post-injury) subjects. Fifteen subjects had visible encephalomalacias whereas 12 did not have evident lesions on MRI. Imaging from 14 age-matched healthy volunteers were used as controls. CBF was assessed by arterial spin labeling (ASL) and CVR by measuring the change in blood-oxygen-level-dependent (BOLD) MRI during a hypercapnia challenge. There was a significant reduction in FA, CBF, and CVR with a complementary increase in MD within regions of FLAIR-visible encephalomalacia (p < 0.05 for all comparisons). In normal-appearing brain regions, only CVR was significantly reduced relative to controls (p < 0.05). These findings indicate that vascular dysfunction represents a TBI endophenotype that is distinct from structural injury detected using conventional MRI, may be present even in the absence of visible structural injury, and persists long after trauma. CVR may serve as a useful diagnostic and pharmacodynamic imaging biomarker of traumatic microvascular injury.

show abstract

Section: Introductionmentioning

confidence: 99%

Vascular Abnormalities within Normal Appearing Tissue in Chronic Traumatic Brain Injury

Haber

Amyot

Kenney

et al. 2018

Journal of Neurotrauma

View full text Add to dashboard Cite

show abstract

“…37 Quantification of rCBF with TDF is highly dependent on patient's core body temperature and is significantly altered in conditions of hyperthermia. 39 Moreover, TDF provides useful data for only 30 to 40% of monitoring time because of monitor dysfunction secondary to placement errors and missing data during recalibrations. 39…”

Section: Thermal Diffusion Flowmetrymentioning

confidence: 99%

“…39 Moreover, TDF provides useful data for only 30 to 40% of monitoring time because of monitor dysfunction secondary to placement errors and missing data during recalibrations. 39…”

Section: Thermal Diffusion Flowmetrymentioning

confidence: 99%

Multimodal Neuromonitoring: Current Scenario in Neurocritical Care

Goyal

Khandelwal

Kedia

2019

Journal of Neuroanaesthesiology and Critical Care

View full text Add to dashboard Cite

Multimodal neuromonitoring (NM) is the concept of integrating various tools and data to understand brain physiology and guide therapeutic interventions to prevent secondary brain injury. There exists a range of invasive/noninvasive and global/regional monitors of cerebral hemodynamics, oxygenation, metabolism, and electrophysiology that can be used to guide treatment decisions after neurological insult. No single monitoring modality is ideal for all patients. Simultaneous assessment of cerebral hemodynamics, oxygenation, and metabolism allows individualized patient care. The ability to analyze these advanced data for real-time clinical care, however, remains intuitive and primitive. Advanced informatics is promising and may provide us a supportive tool to interpret physiological events and guide pathophysiological-based therapeutic decisions. Available literature is not robust regarding multimodality NM and favorable patient outcome. This narrative review is undertaken to know the status and recent advancement of multimodal NM in neurocritical care.

show abstract

“…Cerebrovascular consequences of TBI are in part determined by the type of TBI and include cerebral vasospasm, hemorrhage (epidural, subdural, subarachnoid, and intraparenchymal), and vasogenic edema all of which can result in brain ischemia. TBI involves complex changes in cerebral blood flow (CBF), with some areas (typically proximal to the site of TBI) showing profound hypoperfusion and other areas (typically distal or contralateral to the site of TBI) showing hyperemia (Abrahamson et al, 2013; Akbik et al, 2016). As discussed below, accumulations of Aβ peptides (both oligomeric and fibrillar assemblies) affect cellular components of the NVU and can foster secondary injury processes including activation of cell death pathways (apoptosis), oxidative stress, and inflammation.…”

Section: Neurovascular Unit and The Tbi-ad Linkmentioning

confidence: 99%

Disordered APP metabolism and neurovasculature in trauma and aging: Combined risks for chronic neurodegenerative disorders

Ikonomović

Abrahamson

2017

Ageing Research Reviews

View full text Add to dashboard Cite

Traumatic brain injury (TBI), advanced age, and cerebral vascular disease are factors conferring increased risk for late onset Alzheimer’s disease (AD). These conditions are also related pathologically through multiple interacting mechanisms. The hallmark pathology of AD consists of pathological aggregates of amyloid-β (Aβ) peptides and tau proteins. These molecules are also involved in neuropathology of several other chronic neurodegenerative diseases, and are under intense investigation in the aftermath of TBI as potential contributors to the risk for developing AD and chronic traumatic encephalopathy (CTE). The pathology of TBI is complex and dependent on injury severity, age-at-injury, and length of time between injury and neuropathological evaluation. In addition, the mechanisms influencing pathology and recovery after TBI likely involve genetic/epigenetic factors as well as additional disorders or comorbid states related to age and central and peripheral vascular health. In this regard, dysfunction of the aging neurovascular system could be an important link between TBI and chronic neurodegenerative diseases, either as a precipitating event or related to accumulation of AD-like pathology which is amplified in the context of aging. Thus with advanced age and vascular dysfunction, TBI can trigger self-propagating cycles of neuronal injury, pathological protein aggregation, and synaptic loss resulting in chronic neurodegenerative disease. In this review we discuss evidence supporting TBI and aging as dual, interacting risk factors for AD, and the role of Aβ and cerebral vascular dysfunction in this relationship. Evidence is discussed that Aβ is involved in cyto- and synapto-toxicity after severe TBI, and that its chronic effects are potentiated by aging and impaired cerebral vascular function. From a therapeutic perspective, we emphasize that in the fields of TBI- and aging-related neurodegeneration protective strategies should include preservation of neurovascular function.

show abstract

The Utility of Cerebral Blood Flow Assessment in TBI

Cited by 18 publications

References 103 publications

Vascular Abnormalities within Normal Appearing Tissue in Chronic Traumatic Brain Injury

Vascular Abnormalities within Normal Appearing Tissue in Chronic Traumatic Brain Injury

Multimodal Neuromonitoring: Current Scenario in Neurocritical Care

Disordered APP metabolism and neurovasculature in trauma and aging: Combined risks for chronic neurodegenerative disorders

Contact Info

Product

Resources

About