ABSTRACT
Objective To compare lateral orbital keyhole approach(LOK) with conventional keyhole approach including supraorbital keyhole approach (SOK) and pterional approach(PTK) for exposuring the sellar region and oper-ation ability, to provide theoretical and practical basis for the clinic. Methods From January, 2017 to Feburary, 2018, 15 cadaver head specimens of Chinese (30 sides) fixed by formalin were randomly divided into 3 groups, simu-lating SOK, LOK and PTK, application of frameless neuronavigation system, intersection of the posterior margin of the optic chiasma and the lamina terminalis served as the base point. Six different reference points were selected to radi-ate into the parasellar region of the skull base. The direction of the 2 adjacent reference points were connected to the base point to form a triangle. Six triangles constituted the sellar region to represent the total area. The supratentorial area, ipsilateral area, inferior area and contralateral area were calculated by stacking triangle. The comparison was made between groups. The Salma operation exposure scale was used to simulate the aneurysms of the common parts in the brain and the quantitative scores were performed. Results The total parasellar regions by SOK, LOK and PTK respectively were:(1641.6±295.6)mm2, (1782.3±294.6)mm2 and (1552.5±307.4)mm2. There was no statistical differ-ence(P>0.05); To compare the supratentorial region, SOK and LOK were both bigger than PTK ( P<0.05); To compare the ipsilateral and infratentorial area, LOK and PTK were both bigger than SOK respectively ( P<0.05);To compare the contralateral area, SOK, LOK and PTK were increased in turn (P<0.05). Salma operation exposure scale was used to get the scores:the score of SOK was 29.7 (39.08％), LOK was 37.0 (48.68％), and PTK was 36.1 (47.50％). Conclusion Anatomical analysis displayed that the 3 keyhole approaches showed different exposure of each part the parasellar re-gions, the LOK had a good exposure to the parasellar region and so as the higher maneuverability. But the clinical appli-cation should be comprehensive analysis, pay attention to specific lesions and make an appropriate choice. It has impor-tant clinical significance to improve the prognosis of patients.