Three-dimensional positioning study of the internal structure of petrous bone with the external lower lip of internal acoustic pore as anatomical landmark

Objective: To conduct exact positioning study of the structures inside the petrous bone by creating three dimensional coordinate system with the external lower lip of the internal acoustic pore as its origin. Research design: The three-dimensional model of the petrous bone was established by making nonstaining celloidin section from the right petrous bone of a dead man in an attempt to create original three dimensional coordinate which was later transformed to physical coordinate system. The three dimensional coordinate of each structure inside and outside the petrous bone under the physical coordinate system was measured by choosing the external lower lip of the internal acoustic pore as origin. Results: The three-dimensional model of structures inside and outside the petrous bone was established and coordinate values of each structure inside and outside the petrous bone under the physical coordinate system and relevant distances were measured by selecting the external lower lip of the internal acoustic pore as origin. Conclusion: A certain surface mark of the petrous bone can be chosen as the coordinate origin to make exact positioning study of the structures inside and outside the petrous bone. Correspondence to: Yun-Sheng Li, Department of Anatomy and histology and embryology, Basic Medical College, Tianjin Medical University, QiXiangTai Road 22, HePing District, Tianjin, 300070, China, Tel. +862283336818; E-mail: submission2014@163.com, weixianfeng3@163.com