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Background and purpose: cerebral hemorrhage (intracerebral hemorrhage, ICH) poor prognosis, there is a higher morbidity and mortality and disability rates, but secondary brain injury after ICH mechanism is not clear. This study aims to magnetic resonance (magneticresonance imaging, MRI), intracranial pressure (intracranial pressure, ICP) and brain interstitial fluid microdialysis (microdialysis) monitoring of experimental ICH model used dogs to observe the experimental ICH, MRI performance, ICP changes in interstitial fluid PERIHEMATOMA microdialysis monitoring results, combined with the pathology, further study of secondary brain injury after ICH and mechanisms of evolution. Methods: (1) Select 12 adult male dogs were randomly divided into ICH and saline injected control group 6: (2) the use of Medtronic Navigation system calibration frontal neuroimaging blood injection location and angle bolus non-anticoagulated autologous arterial blood 3 ml (equivalent to the human pro-rata basis 60ml ICH) ICH established animal model frontal dogs, control animals injected with saline at the same site; (3) line blood glucose, blood gas analysis, brain temperature monitoring, determine the ICH group injected with saline control group exists comparability; (4), respectively, were observed dog model and the model prepared before 1 hr after preparation 2 hr, 6 hr, 24 hr, 3 d, 7 d, 14 d at each time point ethology, dynamic MRI observation, at each time point ICP, and the end of the experiment pathology, to determine the reliability of the model, and to study ICP and hematoma surrounding the relationship between brain damage and trends; (5) line microdialysis brain interstitial fluid monitoring, understanding the brain tissue around the hematoma and contralateral brain regions brain interstitial fluid glucose, lactate, pyruvate concentration, glycerol concentration and glutamate concentration, calculated lactate / pyruvate ratio, and injected with saline control group for comparison. Results: (1) In this study, two groups were selected male dogs, exclusion of estrogen on the brain tissue surrounding ICH protection, monitoring blood glucose, blood gas analysis, brain temperature and other basic physical and chemical indicators, the difference was not significant (P <0.05) , there is comparability of monitoring results; (2) injected with saline control group, ICH group ethology rapid shallow breathing after injection of blood, limbs spasticity and other symptoms more obvious, pentobarbital sodium to maintain time and recovery time were prolonged animal experimental animals exist unresponsive, slow, reduced responsiveness to external stimuli, not eating, such as performance is more prominent, and there are different degrees of fear, defensive, brutal and other psychiatric symptoms. (3) MRI examination revealed the presence of saline injected control group, only puncture tract and walked along the lines of the frontal cavity, surrounding no brain edema formation, 7d puncture tract disappearance of cysts slightly expansion, and ICH group appears 2hr after injection of blood perihematoma long T1, T2 signal band, 3d range up to the maximum, 14d around the hematoma persists long T1, T2 signal band, but narrow and the signal is weakened, while red blood cells break down 3d hematoma appears characteristic short T1 short T2 ring, 7d more obviously, 14d small amount of residual hematoma; (4) ICP monitoring found that the two groups are present ICH model after preparation 2hr appear ICP peak and then gradually decline, 3d saline injected control group returned to normal, while the ICH group to 14d end of the experiment remains ICP significantly higher than baseline values ??(P <0.05) and saline injected control group (P <0.01); (5) ICH group pathology results can be seen along the frontal lobe hematoma cavity walk the line, a small amount of residual hematoma, mass effect is not obvious, edema around the hematoma visible, partially visible ipsilateral thalamus scattered spotting, and saline injected control group frontal lobes of the brain to go along the lines of cysts, cysts clean. HE, Nissl staining and transmission electron microscopy were found around the hematoma ICH group neuronal damage and brain edema compared with saline injected control group; (6) interstitial fluid PERIHEMATOMA microdialysis analysis found PERIHEMATOMA glucose concentration in interstitial fluid experiments no significant change in the period, and 3d 24hr elevated lactate concentration (P <0.05), pyruvate concentration in 6hr, 24hr and 3d increased (P <0.05), glycerol concentration in 24hr increased (P <0.05), glutamic acid concentration increased after injection of blood, 3d peak to 14d and the baseline value was still significantly higher (P <0.05). Conclusions: (1) In this study, the frontal lobe of autologous blood injection preparation nonanticoagulant ICH models, model success rate, animal survival, ease of care, can simulate the evolution of clinical ICH. (2) Dogs Brain MRI showed that after 2 hr experimental ICH hematoma appears around long T1, T2 signal band, 3 d range up to the maximum, 14 d around the hematoma persists long T1, T2 signal band, but narrow and the signal is attenuated , while the saline control group injected brain tissue around the cavity MRI showed no abnormal signal, suggesting that blood injection ICH group around the hematoma appears early after brain injury, 3d peak, 14 d brain damage still exist around the hematoma, hematoma surrounding brain injury extent than saline injected control group seriously. (3) ICH early after occupying elevated ICP and around the hematoma hematoma secondary to brain damage caused by common effects, and it is late with elevated ICP after ICH PERIHEMATOMA energy metabolism and excitatory amino acid toxicity caused by secondary brain injury. (4) ICH interstitial fluid surrounding the brain microdialysis monitoring results support the presence of hematoma around \toxicity may be around the hematoma and brain edema formation mechanism of secondary brain injury.
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