Research On Microanatomy Of Petroclival Region

Objective:The petroclival region is located on the basicranial between the middle cranial fossa and posterior cranial fossa.This area is deep and the anatomy structure is complex.Around this area, there is many important structure such as brain stem, IV-XII cranial nerves, internal carotid artery, basilar artery, anterior inferior cerebellar artery, posterior inferior cerebellar artery, jugular bulb, carvernous sinus and so on.The operation to the petroclival region is difficult point of neurosurgery. As the use of new technology such as surgical microscope, endoscope, neuronavigation. The operation impact is improved very much meanwhile the fatality rate and the rate of deformity is decreased substantially. The operation technique on this area is in varied forms. To be familiar with the petroclival region is very important to the operation and choose the aptitude surgical technique.This research is main about the important structures of petroclival region and their relationship though two different operative technique. And than work out the distinctions of the exposure though the two approaches. Method:Ten adult cadaveric specimens (twenty sides) fixed by formalin, perfused with colored silicon and without known intracranial diseases, were used in this study. The classical transpectrosal presigmoid approach (TPA) and the expended middle fossa approach (EMFA) were operated in the two sides of 10 fixed and perfused adult cadaveric heads on random. Than we study and quantifying the exposure of Meckel cavanity,trigeminal ganglion, oculomotor nerve, trochlear nerve, abducent nerve, facial nerve, glossopharyngeal nerve, posterior cerebral artery, superior cerebellar artery, posterior communicating artery, intracranial Artery. Than the data will be statistical analysised using the software spss 10.0.At last,the visual angle and the operation depth of the two approaches are paired t-test, the inspection levelα=0.05.Result:1.The exposure of trigeminal ganglia though the two approaches has no significant difference(P> 0.05), however the exposure of glossopharyngeal nerve has significant difference(P<0.05).2.The line from the foramen spinosum and foramen lacerum is parallel to the line of the both external ear canal. The cochlea and the geniculate ganglion are located out of the line from foramen spinosum to arcuate eminence.The thickness of sclerotin up the internal carotid artery is (3.30±1.05) mm。3.The square measure of the bone piece though EMFA is (21.0±3.5)cm2 and it is significant smaller than the PTA's.Conclusion:1.Both TPA and EMFA can expose the important structure of upper petroclival region clearly.Their visual angle and operation depth have no significant difference.2. The EMFA has shorter incision and smaller bone piece. 3.It has significant advantage to locate the safe boundary by locating the foramen spinosum and arcuate eminence.4.As for the tumor situated in petroclival region which deviated to the middle cranial fossa, we observe that the EMFA has superiority to TPA.