Joint The High Cervical With Jugular Foramen By The Approach Of The Micro-anatomical Study

Objective To investigate the micro-anatomical approach to resect both intracranial and extracranial jugular foramen tumors in one-stage. To study the normal anatomic features of the jugular foramen, in order to provide anatomic data for microsurgical t reatment and the selection of surgical approach to jugular foramen lesions.Methods 15 well-preserved cadaveric wet adult heads fixed with formalin, and inject red and blue latex into two carotids arteries and vertebral jugular vein respectively. With the aid of surgical microscope, cadaver heads were used to study the microsurgical anatomy of high cervical part and jugular foramen, measure relative data. Skull base is to be removed to observe and shoot the microanatomical relationship of important structures such as veins and nerves. Observe and shoot important blood vessels, nerves and their relationship with the fissures around. Mark the important bone at skull base, measure the distance of holes in skull base and undertake statistical analysis whose result will be marked with average±.Results Detailed dissection was performed on high cervical part between the 1st cervical vertebra and the 4th cervical vertebra. resect foramen processus transversi of the 1st cervical vertebra, Free vertebral artery 2nd and 1st cervical vertebra segment and horizontal segment; The jugular tubercle ,jugular Tunisia and part of the occipital condylus was drilled away as much as possible; Total exposure of lateral semicircular canal was completed after the removal of the mastoid revealed labyrinthine; Then thesigmoid sinus and jugular bulb were skeletonized .The vertical of segment of facial nerve was fully skeletonized to study the necessity of the facial nerve translocation . Full exposure to the sigmoid sinus, . JF areas expanded and the measured parameters revealed. The distance was(29.65±3.24)mm from mastoidalec to oncentrated focus of condyle; (10.18±0.81)mm fromhinder margin of condyle to endostoma of hypoglossal canal; The left distance was (6.8±0.35)mm from jugular foramen to perpendicular part of facial nerve ,right was (4.6±0.33)mm. The exposure of the transjugular approach was directed through the jugular process of occipital bone to posterior sur face of jugular bulk (JB). After removal of the mastoid process and the petrous bone under the labyrinth, the vertical segment of facial nerve was skeletoned. The exposure was extended lateral to JF. The transverse process of C1 was removed and the segment of the VA between the transverse foramen of C2 and its entrance of the dura was seperated, the cervical exposure was extended. The tympanomastoid notch and the posterior belly of digastric were closely related to facial nerve.The jugular foramen separated into three parts inferior peterosal sinus and glossopharyngeal nerve anteramedially.The pica may cirdelower to the accessory nerve, passing through the cranial rootlets of accessory nerve or the lower rootlets of vagus nerve, passing through the superiar root-lets of vagus nerve or cirde above the glossopharyngeal nerve.Conclusion The jugular foramen is a complex area. It s anatomical parameters and adjacentst ructure are useful for diagnosis and surgical t reatment of lesions in this area. Detailed anatomic study may improve the success in surgery. The anatomical and imageologic data are useful references for the operationsin the jugular foramen region, which is helpful for avoiding the lesion of vessels and cranial nerves. Total exposure of JF can be achieved through the approach we described, and will enable the facial nerve, cochlea, and the structure of the vertebral artery can be performed. Both intracranial and extracranial tumors can be removed in a one-stage procedure related to anatomical parameters. Improve the cure , reduce complication and lower mortality.