Microsurgical Anatomy Of The Subtemporal Transdural Approach To The Petroclival Region

Objective To provide the anatomic data for the subtemporal transtentor approach To provide an anatomical date for tentorial incision in safty. To explore the anatomical structure and identify the safe resecting region in the temporal base approach of transpetrosal subdura. To explore ways to easy grinding petrousbone.Methods the subtemporal approach was simulated in 10(20sides) formalin-fixed cadaveric adult heads. Observed before and after tentorial incision., the exposed area of petrous apex area and the important microanatomy structure surrounding was measured and photographed. In the premise of tentorial incision. Grond the petrous apex bone in subdura. Observed before and after the grinding of the bone, Revealed the scope and the surrounding importent structures of the petrous apex. Photographed and measured the results of observation. to providing the safety range of the grinding petrous bone. Measured the surgical perspective on before and after the grinding of the bone .Results Before the tentorial cut, the scope revealed was up to the post-clinoid and down to the tentorial. Including the oculomotor nerve, the total length of the posterior communicating artery,the posterior cerebral artery segment P1P2 and the upper basilar artery. The point of intersection of post bedrock folds and tentorial edge can be targeted the point of Trochlear nerve into the tentorial. Tentorial was cut to improve the structure under the tentorial, such as the Aica, Trig.N .Facial nerve and auditory nerve. Subtemporal subdural through the petrous approach,According to the Internal auditory canal with the petrous into the angle and Surface location of the auditory nerve. With the auditory canal as a symbol, Bone is divided into the part of around the internal auditory canal and the petrous apex . to grinding petrous bone in two parts. The bone around the internal auditory canal is devided into the lateral internal auditory canal and upper part. Distance of about 5mm to the internal auditory canal was grinded. Grinding the most anterior border near the bottom of the internal auditory canal. The distance of the internal auditory canal is about about 8.83±0.45mm. To avoid damage the internal auditory canal lateral semicircular canal and the total feet and inside the cochlea.,to protect the patient's hearing. The yard of the inside petrous apex was grinded , Its bord of the innermost to the petroclival fissure, the most down to the inferior petrosal sinus, the most anterior border to the GSPN. The subdural bone grinded operation increasing the vertical angle is about 15°.Conclusion The subtemporal tentorial approach can show increased the structure under the tentorial, Suitable for resection involving Upper and lower tentorial tumors, riding the middle and posterior cranial fossa or petroclival region tumor. subtemporal subdural approach through the petrous bone, petrosum the posterior fossa structures and the formation of petroclival region blocked the vision of the surgery by the petrosum. After grinding bone to improve the structure of the posterior fossa exposed, can increase the surgeon's vertical field of vision, reducing traction on the temporal lobe. The amount of bone grinded according to the need for surgery. It gives the priority exposure the base of posterior fossa tumors. With a relatively simple operation, high security features.