Applied microanatomical study of the jugular foramen region

Objective To study the normal anatomic features of the jugular foramen,in order to provide anatomic data for microsurgical treatment and the selection of surgical approach to jugular foramen lesions.Methods The microsurgical anatomy of the jugular foramen was observed and measured step by step with microscopic skills in 20 jugular foramens of 10 fixed adult head and neck cadavers.The anatomic relationships between the nerves and vessels in this region were observed in detail;particular attention was paid to the compartmentalization of the jugular foramen.The relationships between the caudal cranial nerves and the jugular bulb were analyzed.Results The jugular foramen in the right side was larger than in the left in 7 species.Partial separation of the cranial nerve Ⅸ from the cranial nerves Ⅹ and Ⅺ by fibrous septa(17 species,85%) or bony septa(3 species,15%) was observed.The glossopharyngeal nerve was separated from the fascicles of vagus nerve and accessary nerve by a dural septum at the intracranial opening.Conclusion The jugular foramen is a complex area.Its anatomical parameters and adjacent structure are useful for diagnosis and surgical treatment of lesions in this area.Detailed anatomic study may improve the success in surgery.