Study Of Cerebrospinal Fluid Dynamics In A Model Of Brain Herniation Induced By Acute Intracranial Hypertension By Phase-contrast Cine Magnetic Resonance Imaging

OBJECTIVE: After establishing a stable brain herniation(BH)model induced by acute intracranial hypertension in Guangxi Ba-Ma Mini-Pig,the phase-contrast cine magnetic resonance imaging(PC cine MRI)technology was used to explore the cerebrospinal fluid(CSF)dynamics,which can provide a theoretical basis for Damage Control Neurosurgery(DCNS).METHODS: Ten Guangxi Ba-Ma Mini-Pigs were induced by 2.5 to 3.0%v / v isoflurane and oxygen mixed gas,and 10% chloral hydrate was maintained intravenously to maintain anesthesia.Autologous femoral arterial blood from Ba-Ma Mini-Pigs were extracted and injected into the left frontal,temporal and parietal lobes to establish the BH model of acute intracranial hypertension by microinjection pump.Mean arterial blood pressure(MAP),increased intracranial pressure(ICP)and cerebral perfusion pressure(CPP)were monitored.Before and after autologous arterial blood injection,all experimental animals were routinely scanned with 3.0T MRI,CSF flow velocity and carotidartery flow velocity were measured at the level of cervical 3(C3)vertebral body and perpendicular to the vertebral canal by CSF flow sequence(Fast PC Cine Slice).The changes of ICP,MAP,CPP,CSF peak velocity absolute value and carotid artery peak velocity absolute value before and after autologous arterial blood injection were compared.After the experiment,the animals were executed and pathological examination was performed.RESULTS: Before the injection of autologous arterial blood,the ICP of Guangxi Ba-Ma Mini-Pigs was(6.80±2.044)mmHg,MAP was(76.80±7.068)mmHg,CPP was(70.00±6.074)mmHg,ICP,MAP and CPP gradually increased during injection of autologous arterial blood,compared with the ICP was(52.20±1.619)mmHg,MAP was(142.80±12.399)mmHg,and CPP was(90.50±12.250)mmHg after injection of autologous arterial blood,the differences were statistically significant(P<0.05).The absolute value of CSF peak flow velocity before injection of autologous arterial blood was(243.20±77.671)mm/s,which was significantly different from the absolute value of CSF peak flow velocity after injection of autologous arterial blood(201.40±55.482)mm/s(P<0.05).The absolute value of the peak velocity of the carotid artery blood flow before autologous artery blood injection was(876.80±239.908)mm/s,compared with the absolute value of the peak velocity of the carotid artery blood flow after injection of autologous arterial blood(799.40±241.829)mm/s,there was no significant difference(P>0.05).After injection of autologous arterial blood,head CT and MRI examinations showed that intracranial hematoma formed and BH occurred.Gross specimens showed that most of the hematomas were located in frontal,temporal and parietal lobes.CONCLUSIONS: 1.Using a micro-injection pump to inject autologous arterial blood into the brain of Guangxi Ba-Ma Mini-Pig,a stable animal modelof BH induced by acute intracranial hypertension can be established.2.BH animal model has a low dynamic change in CSF circulation in the ventral spinal cord of C3 level.3.PC cine MRI technology can objectively evaluate CSF dynamics of BH animal model,which can provide a theoretical basis for further study of DCNS in the future.