PC cine MRI对急性颅内高压致脑疝动物模型的脑脊液动力学监测研究

Monitoring of cerebrospinal fluid dynamics in a model of brain herniation induced by acute intracranial hypertension by PC cine MRI

目的探索磁共振相位对比电影成像法(PC cine MRI)对广西巴马小型猪急性颅内高压致脑疝模型的脑脊液(cerebrospinal fluid, CSF)动力学监测。方法抽取10只猪股动脉血,向额颞顶叶内注血制成急性颅内高压致脑疝模型;监测平均动脉血压(mean arterial blood pressure, MAP)、颅内压(intracranial pressure, ICP)、脑灌注压(cerebral perfusion pressure, CPP)。用3.0T磁共振对所有实验动物注血前、注血后行常规颅脑磁共振T1WI轴位,T2WI轴位、冠、矢状位扫描以及以颈3(C3)椎体为中心,垂直于椎管的脑脊液流动序列(fast PC cine slice)扫描。比较注血前后ICP、MAP、CPP、CSF峰值流速绝对值和颈动脉峰值流速绝对值的变化情况。结果注射自体动脉血前ICP为(6.80±2.044)mmHg,MAP为(76.80±7.068)mmHg,CPP为(70.00±6.074)mmHg,CSF峰值流速绝对值为(243.20±77.671)mm/s,与注血后ICP为(52.20±1.619)mmHg,MAP为(142.80±12.399)mmHg,CPP为(90.50±12.250)mmHg,CSF峰值流速绝对值为(201.40±55.482)mm/s相比较,差异均有统计学意义(P < 0.01);注血前颈动脉峰值流速绝对值为(876.80±239.908)mm/s,与注血后颈动脉峰值流速绝对值为(799.40±241.829)mm/s相比较,差异无统计学意义(P > 0.05)。结论急性颅内高压致脑疝形成后,C3水平椎管内CSF流动呈现出低动力学改变,CSF流速波形图紊乱、畸形。PC cine MRI对CSF动力学的无创性测量可为急性颅内高压致脑疝动物模型的CSF动力学的改变提供重要依据,并为将来进一步研究损伤控制神经外科提供理论基础。

Objective To explore the monitoring of cerebrospinal fluid (CSF) dynamics in a model of brain herniation induced by acute intracranial hypertension in Guangxi Bama-Mini pigs by phase-contrast cine magnetic resonance imaging (PC cine MRI). Methods Femoral artery blood were extracted from 10 pigs, and injected into the frontal and temporal parietal lobe to make a model of brain herniation induced by acute intracranial hypertension. The mean arterial blood pressure (MAP), intracranial pressure (ICP), and cerebral perfusion pressure (CPP) were monitored. Routine T1WI, T2WI, coronal, sagittal and cerebrospinal fluid flow sequence (fast PC cine slice) which positioned on the cervical 3 (C3) vertebral body as the center and perpendicular to the spinal scans were performed on all experimental animals before and after blood injection with 3.0T Magnetic Resonance Imaging. The ICP, MAP, CPP, the absolute values of CSF peak flow velocity and the absolute value of carotid peak flow velocity before and after blood injection were compared. Results The ICP, MAP, CPP, and the absolute value of CSF peak flow velocity before injection of autologous arterial blood were statistically significant as compared with those after blood injection [(6.80±2.044) mmHg vs (52.20±1.619) mmHg,(76.80±7.068) mmHg vs (142.80±12.399) mmHg,(70.00±6.074) mmHg vs (90.50±12.250) mmHg, and the absolute value of CSF peak flow velocity was (243.20±77.671) mm/s vs (201.40±55.482) mm/s, respectively, P < 0.01]. The absolute value of the peak velocity of the carotid artery before blood injection was not statistically significant compared with that after blood injection [(876.80±239.908) mm/s vs (799.40±241.829) mm/s, P > 0.05]. Conclusion After the formation of brain herniation induced by acute intracranial hypertension, the CSF flow in the C3 level spinal canal showed a low dynamic change, and the CSF flow velocity waveform was disordered and malformed. The non-invasive measurement of CSF dynamics by PC cine MRI can provide an important basis for the change of CSF dynamics in the model of brain herniation induced by acute intracranial hypertension, and provide a theoretical basis for further research on damage control neurosurgery in the future.