Endoscopic-assisted clinical anatomy of supraorbital keyhole approach

Objective:To study endoscopic anatomical characteristics of supraorbital keyhole approach and evaluate its clinical value.Methods:eight adult cadaveric heads were dissected following the supraorbital subfrontal keyhole approach under microscope.Structure of sellar region and parasellar region were observed and measured under endoscope and microscope respectively.Results:Through different anatomical fissures,with the help of endoscope,we could observe the structures of sellar and whole willis circle without any injury to normal tissues.The distance from internal plate of frontomalar convex to apex anterior clinoid process was(5.96±0.22)cm,and to contralateral apex posterior clinoid process(8.11±0.28)cm;the angle between internal plate of frontomalar convex and apex posterior clinoid process was(32.58±3.44)°,and to contralateral apex anterior clinoid process(50.33±3.44)°.Neuroendoscope can be used to observe the hidden important anatomic structures.Endoscope-assisted micro-neurosurgical technique can make maximal exposure of pathological vessels,with minimal damage to nearby structures.Conclusions:The keyhole approach is available for sellar tumor resection,aneurysm clip,ventriculusostomy trans lamina terminalis,optic canal decompression,and so on.Familiar with the position relation of the structures in the approach is of great value.