The Value Of BAEP Monitoring In The Evaluation Of Vertebrobasilar Ischemia Reperfusion Model

Objectives:1. To investigate the methods of inducing experimental vertebrobasilar ischemia animal model.2. To observe the effect of urokinase in the vertebrobasilar ischemia model.3. To explore the changes of BAEP in the experimental model's vertebrobasilar ischemia reperfusion.Methods:Inducing experimental vertebrobasilar ischemia model with 50% ferric chloride filter paper covered rabbit's bilateral vertebral artery.The rabbits randomly allocated to the control group (sham group), the experimental group, the experimental group also points urokinase therapy group, non-thrombolytic group. The groups are in a mode before and after thrombolysis and in the course of every 30 min, monitoring changes of BAEP and record the results. At the end of the experiment to collect the necessary brain tissue, respectively TTC staining and HE staining to observe pathological changes in brain tissue.Results:1. The dynamic change of BAEP: the experimental group's 12 rabbits, both bilateral leads BAEP, which urokinase thrombolytic therapy group'sⅠ～ⅤPL were shotered after thrombolysis, non-thrombolytic group'sⅠ～ⅤPL gradually extended, some rabbits'ⅣPL,ⅤPL wave division poor, poor reproducibility. Thrombolytic therapy group's PL and IPL before thrombolysis therapy compared with after thrombolysis have statistically significant (P <0.05), the PL and IPL of thrombolytic therapy group after thrombolysis compared with non-thrombolytic group at the corresponding point time,the diffence was significant (P <0.05). The PL and IPL of control group after measured compared with the former have no significance (P> 0.05), and of the experimental group before measured compeared with after measured also have no significance (P> 0.05 ).2. TTC staining results: every group's brain tissue stained by the TTC white infarction were not obvious.3. HE staining results: non-thrombolytic group's brain tissue stained by the HE revealed that the basic structure is normal, and some neuron cells swelling, shrinking, the surrounding cavity formation, glial cells mild hyperplasia, some nerve fibers swelling, have some eosinophilic neurons, in line with the pathological changes in the brainstem ischemia. Thrombolysis group's neurons in the brainstem change was not obvious, control group's brainstem HE staining biopsy without these changes.Conclusion:1. Bilateral vertebral artery induced by ferric chloride success of the vertebrobasilar ischemia model.2. BAEP could timely and sensitively reflect changes in the functions of the brain stem caused by vertebrobasilar ischemia in early, could contribute to the early detection of vertebrobasilar ischemia, and has a clinical significance in guidance on thrombolytic therapy.