Three-dimensional Reconstruction Of The Petrous Bone And Three-dimensional Positioning Study Of The Internal Structure Of Petrous Bone

Objectives We aimed to present a comprehensive three-dimensional (3D) morphology of the petrous bone with the unstained celloidin sections by means of computer image-processing technology, which could make benefits in the assist of anatomic teaching and surgical procedures.3D reconstruction of images could clearly display the detailed surface and internal structures of the petrous bone and their spatial relationships. To conduct exact positioning study of the structures inside the petrous bone by creating three dimensional coordinate system with a certain surface mark of the petrous bone as its origin.Materials and Methods1.The petrous bones come from male cadaveric head in14patients (27lateral temporal bone) and10cases of female cadaver heads (20sides of temporal bone) with no history of otological disease. The specimens were decalcified, dehydrated, embedded in celloidin,and serially sectioned in the horizontal plane. A digital camera(DC) was used to take photos. We observed the refine structure with anatomic microscopy.2.We choose a male and a female patients with bilateral temporal bone sections for modeling.The sections’images were aligned manually in Adobe Phtoshop6.0. The contours of all structures in petrous bone were manually precisely outlined and reconstructed with Amira software, and three-dimensional data set of temporal bone was obtained.3. The three-dimensional model of the petrous bone was established 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 the petrous bone under the physical coordinate system was measured by choosing a certain surface mark of the petrous bone as origin.Results1. The petrous bone come from3cases of male and a female cadaver head were serially sectioned in the horizontal plane at a thickness of40μm～200μm, taking pictures over more than3000. It’s shown that the contour of detailed structure is clearly imaged, such like semicircular canals,the cochlea and vestibular aqueduct et al. Under anatomic microscopy, the details of refine structure could be observed clearly in an enlarging sight. One male and one female petrous bone were for horizontal slices in Alizarin red staining group, collecting pictures of more than1500.2. A wide variety of structures of the human inner ear were reconstructed,inclding petous bone,bone labyrinth,internal carotid artery canal,internal jugular vein canal, pyramidal eminence, et al.3D reconstruction of images clearly displayed the detailed surface and internal structures of the petrous bone and their spatial relationships.3. The three-dimensional model of the petrous bone was established and coordinate values of each structure inside the petrous bone under the physical coordinate system and relevant distances were measured by selecting a certain surface mark of the petrous bone as origin.Conclusion1. The two-dimensional image with petrous bone celloidin sections can clearly observe the fine structure of inner ear, which provide important morphological foundation for image recognition anatomical structures or lesions.2. Our study suggests the feasibility of comprehensive3D reconstruction of petrous bone on the basis of unstained celloidin sections in technique.3D reconstruction of images clearly displayed the detailed surface and internal structures of the petrous bone and their spatial relationships.3.We first established a three dimensional physical coordinate system with the external lower lip of the internal acoustic pore as origin to conduct an exact positioning research into the internal composition of the petrous bone.4. We first made systematic measurements of the coordinates of the internal structures of the petrous bone by using the intersection of greater superficial petrosal nerve and geniculate ganglion, processus cochleariformis and pyramidal eminence as origin.