Comparative Anatomical Study On Surgical Approaches To Tumors In Jugular Foremen

Objectives:Despite a lagre number of approaches to glomus tumors were reported,poor exposure of important anatomy structures in jugulare foramen area were still exits.Therefore,new modified approaches to glomus tumors were Proposed.The objeotive of the study were:To obtain more detailed microanatomy structures and their correlations in jugulare foramen;To compare the exposure level of the important anatomy structures of jugulare foramen between previous surgical approaches and new modifications;To provide anatomic knowledge basis for surgical approach in glomus jugulare tumors of individuals.Methods:In this study,we used 10 cadaver heads(20 sides) fixed with 10%fomraline.The microsurgical anatomy and measurement had been performed under microscope by mimicing lateral approach, hypotympanic approach(HT) and its modified approach,infratemporal fossa type A approach(ITFA) and its modified approache,modified infratemporal fossa type B approach(ITFB).The microsurgical anatomy and anatomy exposure of dura in jugulare foremen areas had been compared in those surgical approaches.Results:The lateral approach can exposure the enviroment of jugulare foramen,parapharyngeal space and some other important anatomy structures outside of skull;The verticals egment of the petrous internal carotid artery,glomus jugulare,as well as infralabyrinthine areas were well exposed in HT approach.Besides,HT approach can preserve the external and middle ear structure.However,the horizontal segment of sigmoid sinus and its surrounding dura,posterior compartment of jugulare foremen,as well as posterior edge of jugulare vein's origin, which were poorly exposed in HT approach,were well exposed in modified HT approach;The vertical segment,genu,and a part of horizontal segment of the petrous intenral carotid artery,as well as middle ear cavity,glomus jugulare and infralabyrinthine areas were well exposed in ITFA approach.However,the horizontal segment of sigmoid sinus and its surrounding dura,posterior compartment of jugulare foremen,as well as posterior edge of jugulare vein's origin,which were poorly exposed in ITFA approach,were well exposed in modified ITFA approach.Another disadvantage is that the external and middle ear structures were destroyed by modified ITFA approach.Modified ITFB approach can further exposure the horizontal segment of petrous intenral carotid artery.Conclusions:It is considered that a large amount of practice to obtain considerable knowledge about anatomy structure in jugulare foremen areas is need toensure the safety surgical operation in this areas.The vertical segment of internal carotid artery,infralabyrinthine areas,glomus jugulare,as well as anterior compartment of jugulare foremen were well exposed in HT approach.Furthermore,HT approach avoids the destruction of the external and middle ear.To further exposed horizontal segment of sigmoid sinus and its surrounding dura,posterior compartment of jugulare foremen,as well as posterior edge of jugulare vein's origin,modified HT approach can be operated.Similar to HT approach,both the cavity of the middle ear and the vertical segment,genu of internal carotid artery can be fully exposed by ITFA approach.Besides,glomusjugulare,infralabyrinthine areas,as well as anterior compartment of the jugulare foremen were well exposed in ITFA approach.To further exposed horizontal segment of sigmoid sinus and its surrounding dura,posterior compartment of jugulare foremen,as well as posterior edge of jugulare vein's origin,modified ITFA can be operated.Compare with modified ITFA approach,modified ITFB approach can further exposure the horizontal segment of petrous intenral carotid artery.