Cerebral Blood Volume Alterations in the Perilesional Areas in the Rat Brain after Traumatic Brain Injury—Comparison with Behavioral Outcome

Abstract

In the traumatic brain injury (TBI) the initial impact causes both primary injury, and launches secondary injury cascades. One consequence, and a factor that may contribute to these secondary changes and functional outcome, is altered hemodynamics. The relative cerebral blood volume (CBV) changes in rat brain after severe controlled cortical impact injury were characterized to assess their interrelations with motor function impairment. Magnetic resonance imaging (MRI) was performed 1, 2, 4 h, and 1, 2, 3, 4, 7, and 14 days after TBI to quantify CBV and water diffusion. Neuroscore test was conducted before, and 2, 7, and 14 days after the TBI. We found distinct temporal profile of CBV in the perilesional area, hippocampus, and in the primary lesion. In all regions, the first response was drop of CBV. Perifocal CBV was reduced for over 4 days thereafter gradually recovering. After the initial drop, the hippocampal CBV was increased for 2 weeks. Neuroscore demonstrated severely impaired motor functions 2 days after injury (33% decrease), which then slowly recovered in 2 weeks. This recovery parallelled the recovery of perifocal CBV. CBV MRI can detect cerebrovascular pathophysiology after TBI in the vulnerable perilesional area, which seems to potentially associate with time course of sensory-motor deficit.

Transplantation of Marrow Stromal Cells Restores Cerebral Blood Flow and Reduces Cerebral Atrophy in Rats with Traumatic Brain Injury: In vivo MRI Study

“…3). In accordance with the view that perfusion compromise is linked to functional deficits (Bonne et al, 2003;Immonem et al, 2010), we found that the reduction of hypoperfusion area was associated with the augmentation of functional recovery as evaluated by mNSS (compare Fig. 3G with Fig.…”

“…As found in the present study, MSCs diminish hemodynamic abnormalities (Fig. 3G) by early restoration of blood flow perfusion to deliver oxygen and glucose, which may rescue neurons at risk from energy deprivation (Immonem et al, 2010). The ability of MSCs to facilitate vascular remodeling (Borlongan et al, 2004), to enhance neurogenesis (Mahmood et al, 2004b), to protect neurons (Wilkins et al, 2009) and to support axonal regeneration (Ankeny et al, 2004), which in turn moderate neuropathological change and white matter degeneration, may contribute to tissue preservation (Fig.…”

Cellular Alterations in Human Traumatic Brain Injury: Changes in Mitochondrial Morphology Reflect Regional Levels of Injury Severity

“…Previously, it was found that different cortical contusion zones ranging from the injury center, through its periphery, to the surrounding penumbra, display specific pathological characteristics, e.g., blood flow and oxygenation, in both human and experimental TBI. [43][44][45][46][47] Considering the dependence of mitochondrial structure and energetics on the availability of biofuel and oxygen, the differences in mitochondrial morphology among these zones is consistent with these gradients.…”

The Effects of Perturbed Cerebral Blood Flow and Cerebrovascular Reactivity on Structural MRI and Behavioral Readouts in Mild Traumatic Brain Injury

“…Thomale et al 20 found severe hypoperfusion (by laser Doppler flowmetry) in the area of the impact at 0.5-6.0 hours and hyperperfusion at 24 and 48 hours in a similar rat model of moderate CCI. Immonen et al 21 found that cerebral blood volume dropped 1 hours after injury, pseudonormalized on days 1-3 and increased on day 4 in a similar CCI model. Other studies found CBF reduction on day 0 using the Marmarou rat model 6 or fluid percussion model 22 but without hyperperfusion on subsequent days after TBI.…”