Anatomic Study On Surgical Exposure Of Supraorbital Keyhole Approach

Part I Anatomic study on exposure scope of supraorbital keyhole approachObjective: To study the surgical exposure of supraorbital keyhole approach so as to discuss the indication of supraorbital keyhole approach.Methods : Supraorbital keyhole approach were performed on formalin-fixed and dye-injected cadaveric head specimens . The maximum exposure scopes of the circle of Willis under the operative microscope were measured and recorded using the neuronavigation . Before the intracranial measurement , the accuracy of neuronavigation was compared with the traditional measurement.Results: 1. Neuronavigation can offer accurate location and measure . 2. 4 spaces of sellar area could be viewed and controlled satisfied via supraorbital keyhole approach .The supraorbital keyhole approach could provide the potential for access to the circle of willis : the maximum exposing length of the ipsilateral MCA and the contralateral ICA and anterior communicating artery complex (AcoA) and basilar artery and posterior cerebral artery (PCA) and superior cerebellar artery (SCA) were 18.7+4.65mm , 7.5+1.65 mm , 5.7+2.35 mm , 6.7+2.29mm , 6.1+1.38mm , 5.9 +1.45mm ,4.3+1.46mm , 4.7+1.70mm, respectively In two cadavers specimens , the basilar artery bifurcation located higher can not be exposured.Conclusion : 1. Application of neuronavigation is very beneficial to the study on microanatomy of skull base . 2.The supraorbital approach is effective for gaining access to the sellar area and absolutely be applied to treat lesions of anterior fossa ,and paraseller region .