Microsurgical anatomy on the design of the far-lateral supracondylar keyhole approach / 中华显微外科杂志

ABSTRACT

Objective To explore the posibility of removing the jugular tubercle precisely and design a new far-lateral supraeondylar keyhole approach based on keyhole idea.Methods Eight cadaveric heads fixed by 10% formalin and perfused intracranial vessels with colored silicone were used in this study.Before the operation,navigation data of these cadaveric heads were established and circumscriptions of jugular tuber- cle were outlined in the navigation system in order to aid drilling it in operation.A 7cm longitudinal“S”shaped skin incision as we reported was performed.After inverting suboccipital muscles and exposing the far lateral of the occipital bone,occipital condyle,jugular tubercle,hemilamina of C_1,vertebral artery and pos- terolateral portion of foramen magnum,a 3cm retro-condylar bone window was made.Under the microscope, anatomic structures were observed and important structures were measured after jugular tubercle removal assis- ted by neuro-navigation.Results The 7cm longitudinal“S”shaped skin incision with its superior border 2cm behind the middle point of mastoid and inferior margin at the level of C_2 can fully meet the needs of the far-lateral supracondylar keyhole approach;jugular tubercle can be drilled satisfactorily with the help of neuro- navigation;inferior segment of basilar artery[long(15.65?1.34)mm]and anterior inferior cerebellar artery [long(20.36?4.18)mm] can be exposed.Conchlsion Owing to the area of middle clivus is increasingly exposed after removal of jugular tubercle,it is feasible to perform the far-lateral supracondylar keyhole ap- proach on the operations of vertebral-basilar artery aneurysm,anterior inferior cerebellar artery aneurysm and tumor located inferior and middle clivi or jugular foramen.