Genetic Variation and Impact on Outcome in Traumatic Brain Injury: an Overview of Recent Discoveries

PURPOSE OF REVIEW

Traumatic brain injury (TBI) has a significant burden of disease worldwide and outcomes vary widely. Current prognostic tools fail to fully account for this variability despite incorporating clinical, radiographic, and biochemical data. This variance could possibly be explained by genotypic differences in the patient population. In this review, we explore single nucleotide polymorphism (SNP) TBI outcome association studies.

RECENT FINDINGS

In recent years, SNP association studies in TBI have focused on global, neurocognitive/neuropsychiatric, and physiologic outcomes. While the APOE gene has been the most extensively studied, other genes associated with neural repair, cell death, the blood-brain barrier, cerebral edema, neurotransmitters, mitochondria, and inflammatory cytokines have all been examined for their association with various outcomes following TBI. The results have been mixed across studies and even within genes. SNP association studies provide insight into mechanisms by which outcomes may vary following TBI. Their individual clinical utility, however, is often limited by small sample sizes and poor reproducibility. In the future, they may serve as hypothesis generating for future therapeutic targets.

[Dural Arteriovenous Fistula]

Dural arteriovenous fistulas(dAVFs), which are arteriovenous shunts between the dural/epidural artery and dural vein and/or dural venous sinus, can cause various symptoms, and the risk of aggressive symptoms such as cerebral hemorrhage and venous infarction mainly depends on venous drainage patterns in patients. Patients with dAVFs with cortical venous reflux have a high risk of aggressive symptoms due to cerebral venous congestion or varix rupture, and they often develop brain edema and/or hemorrhage. In some cases, patients with dAVFs may have CT and MRI findings similar to those of patients with brain tumors. Key MRI findings suggesting dAVFs include multiple small flow voids representing cortical venous reflux adjacent to the hemorrhage or edematous lesion on T2WI and dot-like high-signal-intensity patterns of the feeding arteries and draining veins on time-of-flight MR angiography source images. Cerebral angiography should be performed quickly when dAVFs are suspected with careful assessment using CT/MRI to prevent further worsening of symptoms, particularly for lesions involving the brain stem and cerebellum.

Memantine protects blood-brain barrier integrity and attenuates neurological deficits through inhibiting nitric oxide synthase ser1412 phosphorylation in intracerebral hemorrhage rats: involvement of peroxynitrite-related matrix metalloproteinase-9/NLRP3 inflammasome activation

Memantine has demonstrated beneficial effects on several types of brain insults via therapeutic mechanisms mainly related to its activity as a receptor antagonist of N-methyl-d-aspartate. However, the influences of memantine on intracerebral hemorrhage (ICH) remain obscure. This research probed into the neurovascular protective mechanisms of memantine after ICH and its impacts on neuronal nitric oxide synthase (nNOS) ser1412 phosphorylation. ICH model was established by employing intrastriatal collagenase injection in rats. After modeling, rats were then allocated randomly into sham-operated (sham), vehicle-treated (ICH+V), and memantine-administrated (ICH+M) groups. Memantine (20 mg/kg/day) was intraperitoneally administered 30 min after ICH and thenceforth once daily. Rats were dedicated at 0.25, 6, 12, 24 h, 3 and 7 d post-ICH for measurement of corresponding indexes. Behavioral changes, brain edema, levels of nNOS ser1412 phosphorylation, peroxynitrite, matrix metalloproteinase (MMP)-9, NLRP3, IL-1β and numbers of dying neurons, as well as the cellular localization of gelatinolytic activity, were detected among the groups. Memantine improved the neurologic deficits and mitigated brain water content, levels of MMP-9, NLRP3, IL-1β and dying neurons. Additionally, treatment with memantine also reduced nNOS ser1412 phosphorylation and peroxynitrite formation compared with the ICH+V group at 24 h after ICH. In situ zymography simultaneously revealed that gelatinase activity was primarily colocalized with vessel walls and neurons. We concluded that memantine ameliorated blood-brain barrier disruption and neurologic dysfunction in an ICH rat model. The underlying mechanism might involve repression of nNOS ser1412 phosphorylation, as well as peroxynitrite-related MMP-9 and NLRP3 inflammasome activation.

"Computed Tomography Perihematomal Rims": A Perihematomal Low-Density Area Is a Part of an Acute Brain Hemorrhage

Objective Computed tomography (CT) can be used for visualizing acute intracerebral hemorrhages (ICHs) as distinct hyperdense areas and cerebral edema as perihematomal low-density areas (LDAs). We observed a perihematomal LDA on CT, which appeared to be part of a hemorrhage on magnetic resonance imaging (MRI) in acute ICH. We named this "CT perihematomal rim" and evaluated its characteristics and clinical significance. Methods We stratified patients with acute ICH according to the presence or absence of a CT perihematomal rim and then compared their radiologic findings. Logistic regression analyses were performed to assess whether the CT findings can predict the presence of a CT perihematomal rim. Patients Patients within 24 hours of ICH onset who were admitted between September 1, 2014, and October 31, 2018, were registered. Results Overall, 139 patients (91 men; mean age, 66 years) were investigated. CT perihematomal rims were observed in 40 patients (29%). ICH volumes on CT were 30% smaller than those on MRI in patients with CT perihematomal rims. On a multivariate analysis, the presence of a CT perihematomal rim was independently associated with the maximum diameter of the perihematomal LDA. According to a receiver operating characteristic analysis, the maximum LDA diameter threshold was 7.5 mm (sensitivity, 85%; specificity, 83%). Conclusion CT perihematomal rims were observed in 29% of the patients with acute ICH. A perihematomal LDA (>7.5 mm) in acute ICH cases should be considered a CT perihematomal rim. Clinicians should be aware that the ICH volume on CT may be underestimated by 30%.

Neuroendocrine Dysfunction in the Acute Setting of Penetrating Brain Injury: A Systematic Review

BACKGROUND

Data on neuroendocrine dysfunction (NED) in the acute setting of penetrating brain injury (PBI) are scarce, and the clinical approach to diagnosis and treatment remains extrapolated from the literature on blunt head trauma.

METHODS

Three databases were searched (PubMed, Scopus, and Cochrane). Risk of bias was computed using the Newcastle-Ottawa Scale, or the methodological quality of case series and case reports, as indicated. This systematic review was registered in PROSPERO (42020172163).

RESULTS

Six relevant studies involving 58 patients with PBI were included. Two studies were prospective cohort analyses, whereas 4 were case reports. The onset of NED was acute in all studies, by the first postinjury day. Risk factors for NED included worse injury severity and the presence of cerebral edema on imaging. Dysfunction of the anterior hypophysis involved the hypothalamic-pituitary-thyroid axis, treated with hormonal replacement, and hypocortisolism, treated with hydrocortisone. The prevalence of central diabetes insipidus was up to 41%. Most patients showed persistent NED months after injury. In separate reports, diabetes insipidus and hypocortisolism showed an association with higher mortality. The available literature for this review is poor, and the studies included had overall low quality with high risk of bias.

CONCLUSIONS

NED seems to be prevalent in the acute phase of PBI, equally involving both anterior and posterior hypophysis. Despite a potential association between NED and mortality, data on the optimal management of NED are limited. This situation defines the need for prospective studies to better characterize the clinical features and optimal therapeutic interventions for NED in PBI.

Protease-activated receptor 1 inhibitor improves brain edema in rats with intracerebral hemorrhage

AIM

To investigate the changes of water content in brain tissue, the expression of AQP4mRNA after cerebral hemorrhage in rats, and the intervention effect of Protease activated receptor 1 inhibitor (PAR1 inhibitor) on both.

METHODS

Establish sham operation group (Sham group), ICH group, ICH+PAR1 inhibitor high-dose group (PI(H)group), ICH+PAR1 inhibitor low-dose group (PI(L)group), 25 in each group. Neural dysfunction scores were performed at 1d, 3d, 7d, 14d, and 21d after surgery, and brain water content and AQP4mRNA content were measured.

RESULTS

Results: The neurological dysfunction and cerebral edema of rats with cerebral hemorrhage reached the peak at 3 days after operation. With the increase of time, the water content and AQP4mRNA content in the PL(H)group were higher than those in the PI(L)group. The differences were statistically significant.

CONCLUSIONS

Appropriate inhibition of PAR1 can alleviate cerebral edema around the hematoma and play a role in improving the function of nerve defects. The mechanism may be realized by down-regulating the expression of AQP4mRNA in brain tissue (Tab. 3, Fig. 3, Ref. 25).

[Blocking ERK signaling pathway lowers MMP-9 expression to alleviate brain edema after traumatic brain injury in rats]

OBJECTIVE

To investigate the effects of blocking the activation of ERK pathway on the expression of matrix metalloproteinase-9 (MMP-9) and the formation of cerebral edema in SD rats after brain injury.

METHODS

Ninety SD rats were randomly divided into 3 equal groups, including a sham-operated group, modified Feeney's traumatic brain injury model group, and ERK inhibition group where the ERK inhibitor SCH772984 (500 μg/kg) was injected via the femoral vein 15 min before brain trauma. At 2 h and 2 days after brain trauma, the permeability of blood-brain barrier was assessed by Evans blue method, the water content of the brain tissue was determined, and the phosphorylation level of ERK and the expression level of MMP-9 mRNA and protein were measured by RT-PCR and Western blotting.

RESULTS

Compared with the sham-operated group, the rats with brain trauma exhibited significantly increased level of ERK phosphorylation at 2 h and significantly increased expression of MMP-9 mRNA and protein 2 days after the injury (P < 0.01). Treatment with the ERK inhibitor significantly decreased the phosphorylation level of ERK after the injury (P < 0.01), suppressed over-expression of MMP-9 mRNA and protein 2 days after the injury (P < 0.01). The permeability of blood-brain barrier increased significantly 2 h after brain trauma (P < 0.05) and increased further at 2 days (P < 0.01); the water content of the brain did not change significantly at 2 h (P > 0.05) but increased significantly 2 d after the injury (P < 0.01). Treatment with the ERK inhibitor significantly lowered the permeability of blood-brain barrier and brain water content after brain trauma (P < 0.01).

CONCLUSIONS

Blocking the activation of ERK pathway significantly reduced the over-expression of MMP-9 and alleviates the damage of blood-brain barrier and traumatic brain edema, suggesting that ERK signaling pathway plays an important role in traumatic brain edema by regulating the expression of MMP-9.

A Comparative Study Between 20% Mannitol and 3% Hypertonic Saline for Brain Oedema Reduction during Elective Brain Tumour Surgery

Cerebral oedema is an important manifestation of brain tumour. The significant reduction of cerebral oedema can show rapid improvement of the patients. Hypertonic saline solution and mannitol both are commonly used for this action. It is now time to choose the better one. This was a prospective randomized comparative study designed to evaluate the efficacy of 3% hypertonic saline (NaCl) in reduction of brain oedema during brain tumour surgery and compare it with that of 20% Mannitol. The study was conducted in the department of Anaesthesiology, Combined Military Hospital, Dhaka, Bangladesh from July 2016 to December 2016. A total number of 47 patients for brain tumour surgery were selected. After screening 40 patients were finalized. Then the patients were divided into 2 equal groups 20 patients in each. Patients of Group A received 3% hypertonic saline and Group B 20% mannitol. Uniform anaesthetic technique applied for all patients, fixed surgeon/group of surgeons carried out the surgery. Heart rate and noninvasive blood pressure were monitored and kept with in ±20% baseline values different means. ETCO2 were kept in between 28-32mm of Hg by adjusting ventilator setting. Reduction of brain oedema was monitored by subjective assessment of surgeons using a 3 point scale of brain relaxation. The data were recorded in preformed data sheet. The results were tested by chi-square test to see their level of significance i.e. p value <0.05 was considered as significant. At the opening of dura, the number of brain conditions classified as soft, adequate and tight were statistically non-significant between groups. After 0.5 hour and 1.0 hour 10% patient's brain was tight in Group A whereas it was 35% and 40% in Group B respectively. Reduction of brain oedema or brain relaxation was significantly better in Group A compared to Group B (p<0.05). Urine output was higher with mannitol than hypertonic saline (p<0.05). Duration of ICU and hospital stay in both Group A and Group B were statistically similar (p>0.05). Compared to mannitol, hypertonic saline caused an increase in serum sodium concentration over time (p<0.05). From the available data, use of 20% mannitol and 3% hypertonic saline for brain oedema reduction, it is suggested that hypertonic saline significantly reduces the risk of tight brain and produce the brain more soft than mannitol during brain tumour surgery.

Clinical Features and Location of Intracranial Edema in Posterior Reversible Encephalopathy Syndrome (PRES) Patients

This is an observational analytic study on clinical features and location of intracranial edema in case of posterior reversible encephalopathy syndrome (PRES). Place of study was Square Hospitals Ltd. Dhaka, Bangladesh. Study period was 1 year (from January 2010 to January 2011). Number of total cases was 5. Mean age of patients was 21 years. Common clinical features were headache, seizure and visual disturbance. Mean time of developing clinical feature(s) was 4.6 days after NVD or LUCS. Intracranial edema was common in occipital, frontal and parietal lobes.

[Treatment options for acute respiratory distress syndrome in neurointensive care. Individual management due to enhanced neuromonitoring? : A case report series]

Severe pulmonary impairment can occur after traumatic brain injury or stroke. The resulting brain-lung interactions represent key points for the treatment and the subsequent outcome of the patient. Established treatment approaches, such as permissive hypercapnia and prone positioning, present the intensive care physician with divergent treatment goals in these patients with partially increased intracranial pressure. This case report series shows the instrument-based and noninstrument-based options for the treatment of acute respiratory distress syndrome (ARDS) in the simultaneous presence of intracranial pathologies. This includes equipment based therapies using extracorporeal CO₂ elimination, special positioning maneuvers in specially designed hospital beds and positional maneuvers, such as prone positioning. With enhanced neuromonitoring it is possible to optimally adapt treatment measures focused on the lungs early and before secondary damage to the brain.

Histone Deacetylation 10 Alleviates Inflammation After Intracerebral Hemorrhage via the PTPN22/NLRP3 Pathway in Rats

The NOD-like receptor family Pyrin domain-containing 3 (NLRP3) inflammasome has a crucial role in the inflammatory process that occurs during intracerebral hemorrhage (ICH)-induced injury. Histone deacetylase 10 (HDAC10) is a newly identified class II histone deacetylase involved in immune responses. However, how HDAC10 affects the inflammatory response after ICH remains unknown. In this study, we investigated whether HDAC10 relieves ICH injury by suppressing NLRP3 inflammasome activation through the protein tyrosine phosphatase, nonreceptor type 22 (PTPN22) pathway. We induced ICH in Sprague-Dawley rats (healthy, male adult) with a single infusion of autologous blood. To knockdown HDAC10, we injected siRNA into the rats. To further explore the mechanisms underlying the role of HDAC10 in ICH injury, PTPN22 was silenced. HDAC10 levels were upregulated after ICH in humans and rats, and reached peak levels 24 h after ICH induction in rats. HDAC10 silencing aggravated ICH injury, as demonstrated by increased modified neurological severity scores, brain water content, Evans blue extravasation, and number of myeloperoxidase (MPO) cells, and the results of Nissl and H&E staining. Furthermore, HDAC10 knockdown increased the expression of PTPN22 and accentuated inflammatory responses mediated by the NLRP3 inflammasome. HDAC10 silencing increased NLRP3 inflammasome activation, and this was effectively reversed by PTPN22 knockdown using siRNA. Furthermore, HDAC10 silencing also promoted the interaction of PTPN22 and NLRP3. Our study demonstrated that HDAC10 silencing aggravated NLRP3-mediated inflammatory responses after ICH in rats via the PTPN22 pathway. These results suggest that regulating the NLRP3 inflammasome may be a novel method to ameliorate ICH injury.

Underlying Mechanisms and Potential Therapeutic Molecular Targets in Blood-Brain Barrier Disruption after Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a subtype of hemorrhagic stroke with significant morbidity and mortality. Aneurysmal bleeding causes elevated intracranial pressure, decreased cerebral blood flow, global cerebral ischemia, brain edema, blood component extravasation, and accumulation of breakdown products. These post-SAH injuries can disrupt the integrity and function of the blood-brain barrier (BBB), and brain tissues are directly exposed to the neurotoxic blood contents and immune cells, which leads to secondary brain injuries including inflammation and oxidative stress, and other cascades. Though the exact mechanisms are not fully clarified, multiple interconnected and/or independent signaling pathways have been reported to be involved in BBB disruption after SAH. In addition, alleviation of BBB disruption through various pathways or chemicals has a neuroprotective effect on SAH. Hence, BBB permeability plays an important role in the pathological course and outcomes of SAH. This review discusses the recent understandings of the underlying mechanisms and potential therapeutic targets in BBB disruption after SAH, emphasizing the dysfunction of tight junctions and endothelial cells in the development of BBB disruption. The emerging molecular targets, including toll-like receptor 4, netrin-1, lipocalin-2, tropomyosin-related kinase receptor B, and receptor tyrosine kinase ErbB4, are also summarized in detail. Finally, we discussed the emerging treatments for BBB disruption after SAH and put forward our perspectives on future research.

[CT perfusion analysis on the association of permeability surface with hematoma and edema volume in acute spontaneous putaminal and thalamic hematoma]

Objective: To discuss the correlation of permeability surface (PS) with hematoma and edema volume in acute spontaneous putaminal and thalamic hematoma using CT perfusion imaging. Methods: A total of 48 acute spontaneous putaminal and thalamic hemorrhage patients were enrolled in this study during October 2015 and December 2016 at the First Affiliated Hospital of Wenzhou Medical University. At the image slice with maximum size of hematoma, PS was measured by drawing various regions of interest (ROI) including"hot spots", perihematomal regions, outward regions, hemisphere regions and contralateral mirror regions. The relative PS (rPS) was calculated as the ratio of ipsilateral to contralateral PS value in each ROI. Hematoma and edema volumes were traced and obtained with commercial software. Results: The"hot spots"PS ((2.8±1.5) ml·100 g(-1)·min(-1)) and perihematomal PS ((2.1±1.4) ml·100 g(-1)·min(-1)) were both significantly higher than the PS of the contralateral mirror regions ((1.1±0.5) ml·100 g(-1)·min(-1)) (P<0.001). There was no significant difference in outward regions PS and contralateral mirror regions PS (P>0.05), nor in hemisphere regions PS and contralateral mirror regions PS (P>0.05). There was no significant difference in"hot spots"rPS and perihematomal rPS (P=0.218). The"hot spots"rPS and Perihematomal rPS were both higher than the rPS of the outward and hemisphere regions (P<0.01). There was no significant difference in the outward and hemisphere regions (P<0.01). The median hematoma volume was 12.63 ml and the median edema volume was 12.36 ml. The edema volume had a positive association with the hematoma volume(r=0.799, P<0.001) and perihematomal PS(r=0.465, P=0.001). Perihematomal PS had a positive association with the hematoma volume (r=0.386, P=0.007). Conclusion: The damage of blood-brain barrier around acute spontaneous hematoma can be measured via CT perfusion imaging. Perihematomal PS was associated with the hematoma and edema volume.

Hemiconvulsion-Hemiplegia-Epilepsy Syndrome in a Girl Presented with Complex Partial Seizures

The mechanisms underlying the Hemiconvulsion-Hemiplegia-Epilepsy syndrome remains unclear. The current proposed pathogenic mechanism is a neuronal injury induced by venous thrombosis and/or hypoxia. Children develop hemispheric brain atrophy with contralateral hemiplegia, epilepsy, and a variable degree of cognitive deficit. We report a 33 months old female child a case of hemiconvulsion-hemiplegia-epilepsy syndrome with right hemisphere unilateral brain edema and left sided hemiplegia and aphasia who presented with left upper extremities complex partial seizures with generalization to tonic clonic seizures and developed status epilepticus that posed diagnostic and therapeutic challenges. Progressive atrophy of the right cerebral hemisphere was noted after 3 months of follow up. Hemiconvulsion-Hemiplegia-Epilepsy syndrome should be suspected in a child with unilateral cerebral hemisphere brain edema and hemiplegia with cognitive deficit following status epilepticus to provide patients and families with an accurate prognosis regarding the subsequent development of epilepsy.

The Possible Role of Mast Cells and VEGF in Peritumoural Oedema of Secretory Meningioma

OBJECTIVE

Secretory meningiomas constitute a relatively rare subtype of meningiomas and present often with massive peritumoural oedema. From our previous report, a high number of mast cells were demonstrable in this subtype of meningiomas. The present study aimed to obtain more information about mast cell derived progangiogenic factors and mediators as well as VEGF receptors in secretory meningioma. Additionally, the correlation of histological factors such as the presence of mast cells and the radiological evidence of surrounding tumour oedema was analysed.

MATERIAL AND METHOD

Sixteen cases of secretory meningioma were examined. Relevant clinical information was obtained from the patient files. The peritumoural oedema was determined either by CT or MRI scans and graded as mild, moderate and severe. Immunohistochemical studies of histamine, substance P, serotonin, VEGF and VEGF receptors were performed. A double-blind quantitative evaluation of mast cells staining positively for VEGF in a comparison with total mast cells in secretory meningiomas was made by two histopathologists.

RESULTS

There was no immunoreactivity against histamine or substance P within the tumour tissue or in mast cells. Fine granules of serotonin were demonstrated within the mast cells and a coarse granular expression of VEGF was found within the mast cells. Our preliminary data demonstrated that tumours with moderate to severe degree of peritumoural oedema usually contained more than 50% of VEGF-staining positive mast cells.

CONCLUSION

Secretory meningiomas are characterized by a significantly increased number of mast cells. VEGF and serotonin might be involved in the pathophysiological process of this vasogenic brain oedema. The preliminary data demonstrated the potential relation between the radiological evidence of increasing oedema and the high numbers of mast cell staining positively for VEGF.

[Effects of hydrogen-rich water on the expression of aquaporin 1 in the cerebral cortex of rat with traumatic brain injury]

OBJECTIVE

To investigate the effect of hydrogen-rich water on cerebral edema and aquaporin 1 (AQP1) expression in rats with traumatic brain injury (TBI).

METHODS

Ninety male Sprague-Dawley (SD) rats were randomly divided into sham operation group, TBI model group, hydrogen-rich water treatment group (H group),with 30 rats in each group. TBI model was reproduced by weight dropping method. The skulls of rats in sham operation group underwent only craniotomy without direct hit and with bone wax sealed suture.5 mL/kg of hydrogen-rich water injection was given intraperitoneally after model reproduction in H group, and equal amount of normal saline was given in sham and TBI groups, once a day for both groups for 5 days. Six rats from each group were sacrificed at 6,12,24,48 hours and 5 days after evaluating neurological severity scores (NSS).The cerebral cortex was harvested, and the pathological changes in morphology of brain tissue were observed with light microscope. The positive expression of AQP1 in cerebral cortex was observed with immunohistochemistry by light microscopy, the AQP1 mRNA expression in cerebral cortex was determined by real-time fluorescent quantization reverse transcription-polymerase chain reaction (RT-PCR),and the AQP1 protein expression in cerebral cortex was determined by Western Blot.

RESULTS

① All rats in sham operation group had a NSS of zero at each time point. NSS of TBI group was obviously raised with time prolongation, and peaked at 24 hours followed by a lower tendency, while the score in H group was significantly lower than that of TBI group, and the difference was the most obvious at 24 hours as compared with TBI group (9.83 ± 2.78 vs.13.50± 2.42,P ＜ 0.05).② It was shown by light microscope that in the TBI group there were pathological changes in cerebral cortex, including obvious irregular arrangement of nerve cells, cerebral edema, obvious bleeding, especially at 24 hours, then the cerebral edema became vanished gradually; and the positive expression of AQP1 in the pia mater at all the time points in the TBI group was significantly increased, and it was most obvious at 24 hours. Compared with TBI group, the pathological changes at time points of 12 hours to 5 days in H group was significantly lessened, and the positive expression of AQP1 in the cerebral pia mater was reduced obviously.③ Compared with sham operation group, the mRNA and protein expressions of AQP1 in cerebral cortex in TBI group were significantly elevated, peaked at 24 hours [AQP1 mRNA (2-△△Ct):7.50±0.26 vs.1,AQP1 protein (gray value):1.986±0.110 vs.0.336±0.034, both P ＜ 0.05], then they gradually declined. The mRNA and protein expressions of AQP1 in cerebral cortex were significantly decreased after hydrogen-rich water treatment [24-hour AQP1 mRNA (2-△△Ct):5.40±0.21 vs.7.50±0.26, 24-hour AQP1 protein (gray value): 1.246±0.137 vs.1.986±0.110, both P ＜ 0.05].

CONCLUSIONS

The up-regulation of AQP1 mRNA and protein in rats' cerebral cortex after TBI perhaps participates in edema formation which might be involved in the pathophysiology of cerebral edema in TBI. Early treatment with an intraperitoneally injection of hydrogen-rich water is capable of attenuating the extent of TBI-induced up-regulation of AQP1 mRNA and protein, alleviating cerebral edema, and achieving its protective effects.

[CT perfusion imaging evaluation on hemodynamic changes of acute spontaneous intracerebral hemorrhage surrounding tissues]

OBJECTIVE

To discuss the hemodynamic changes in patients with acute supratentorial spontaneous intracerebral hemorrhage (within 72 hours) by using 320-slice of low-dose volume CT perfusion imaging.

METHODS

Twenty-six patients of The First Affiliated Hospital of Wenzhou Medical University during December 2012 to December 2013 with acute supratentorial SICH diagnosed by plain CT scanning and clinic were enrolled. With hematoma maximum level for reference, the hematoma volume, edema area and perfusion defect area were measured, and the perfusion parameters values of the marginal area and outer area of the intracerebral hematoma and contralateral mirror area were measured, including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and time-to-peak (TTP), and rCBF, rCBV, rMTT and rTTP were calculated by ipsilateral/contralateral value.

RESULTS

The CBF, CBV of the marginal area were lower than the contralateral mirror area (tCBF=-8.125, tCBV=-8.671, PCBF, CBV<0.01); the MTT of the marginal area was shorter than the contralateral mirror area (tMTT=-3.246, PMTT<0.05); the TTP of the marginal area was longer than the contralateral mirror area (tTTP=5.027, PTTP<0.01). The CBV of the outer area was lower than the contralateral mirror area (tCBV=-2.337, PCBV<0.05); the MTT of the outer area was shorter than the contralateral mirror area (tMTT=-2.421, PMTT<0.05); the TTP of the outer area was longer than the contralateral mirror area (tTTP=2.077, PTTP<0.05). There was a siginificant relationship between the volume of acute hematoma and rCBV, rMTT, rTTP of the marginal area (rrCBV=-0.412, PrCBV<0.05, rrMTT=-0.437, PrMTT<0.05, rrTTP=0.475, PrMTT<0.05). Perihematomal CBF perfusion defect area showed a positive linear relation with the volume of acute hematoma (r=0.440, P<0.05). There was a positive linear relationship between the maximum level edema area and the hematoma volume, perihematomal CBF perfusion defect area (r=0.400, r=0.81, P<0.05).

CONCLUSIONS

320-slice of low-dose and volume CT perfusion imaging can perfectly reflect the hemodynamic changes in brain tissuse after acute supratentorial SICH. Hypoperfusion was appeared in perihematomal area of acute supratentorial SICH. The perihematomal brain tissue may exists ischemic injury associated with the size of hematoma.The hematoma place holder effect, ischemic injury are the important cause of acute brain edema formation.