兔脑脊液经视神经路径回流到淋巴系统的研究

The optic nerve route for cerebrospinal fluid drainage into the peripheral lymphatic system in rabbits

目的探讨兔视神经鞘蛛网膜下腔（SAS）内脑脊液淋巴回流的路径及初步机制。方法（1）X线脑池造影：经枕大池注射欧乃派克（0．1ml／min），注射后1、10、20、30及60min分别行X线摄影；（2）Microfil 脑池灌注：在5～10min内，经枕大池注射Microfil 20ml，手术显微镜和光镜下观察其分布。结果造影剂注射后20min，视神经鞘SAS开始显影并向眼球和眶周扩散。Microfil 主要分布在颈深淋巴管，包绕在视神经周围，并在视神经入视网膜处集中分布。光镜检查示Microfil 沿视神经鞘SAS长轴纵行分布，动脉及静脉内未见。结论视神经鞘脑脊液经结膜周围淋巴管回流到颈部淋巴系统，这种回流路径对阐明颅内压增高视力损害机制有一定意义。

Objective To explore the route and preliminary mechanism of cerebrospinal fluid drainage from subaraehnoid space （SAS） along the optic nerve sheath into the lymph system. Methods （ 1 ） X-ray cisternography：Omnipaque （0.1 ml/min） was injected into the eisterna magna of the rabbit over 60 min. X-ray studies were performed at 1,10,20,30 and 60 min respectively after starting the infusion;（2） Subarachnoid injection of Mierofil： During 5-10 min,20 mL Mierofil was injected into the cisterna magna. The SAS of the optie nerve sheath of the rabbit was observed by X-ray, microscopic anatomy and light microscopy. Results Under X-ray eisternography,the contrast medium was found in the SAS of the optic nerve sheath and extended to conjunetival sac and orbital cavity. Under the operative microscope, Mierofil was found within the SAS of the optic nerve sheath and accumulated in the conjunction optic nerve with retina. Superfieial and deep cervical lymphatic stained in yellow was identified. Light microscopically, Microfil was distributed around the optic nerve sheath and within the SAS. Conclusion The cerebrospinal fluid drains from the SAS along the optic nerve sheath into the cervical lymph system. The presence of this route may play an important role in understanding the mechanism of papilledema and impairment of vision due to the high intracranial pressure.