Studies On Three Dimensional Reconstruction Of Microstructures In Spinal Cord Of Human And Rat With Serial Sections

Objective: To make three dimensional (3D) reconstruction of microstructures in spinal cord of normal human and rat, using histological serial sections and 3D reconstruction software, as well as to observe and analyze the reconstructed structures.Methods: (1) The human lumbar cord segment serial sections were directly mounted, then stained with Luxol Fast Blue (LFB), the images were collected and stitched. The images underwent"Gray scale","Invert","Image size diminution"in Photoshop7.0 software and received surface and volume reconstruction in 3D-DOCTOR4.0 software. (2) Normal cervical cord segment of SD rat was embeded in paraffin block, four locating marks were made at four corners around specimen, the specimen was sectioned serially with Leica paraffin microtome, after each three sections, the images of specimen and outer locating marks were taken with CANON digital camera and the serial sections were obtained. The obtained images were ordered, cut, turned into gray scale images and background uneven corrected. The edges of white matter, grey matter and locating marks in each image were extracted, the locating marks were used for automated registration of serial sections with 3D-DOCTOR software, 3D surface reconstruction of cervical cord segment was observed, cut and measured freely in PC. (3) The serial transversal sections of rat's spinal cord were made and mounted directly, then stained with LFB and their images were taken. The section images were registered, segmented and changed into gray-scale images under the Photoshop circumstance. 3D-DOCTOR software was used to make threshold segmentation and to reconstruct spinal cord, grey matter and bilateral corticospinal tracts (CSTs) of rat. The reconstructed structures were observed at random angle, dissected and measured in PC.Results: (1) The reconstructed human lumbar cord segment and its grey matter were three dimensional, and could be observed and measured randomly. (2) The grey matter, white matter of rat cervical cord segment were reconstructed from serial transverse sections, the reconstructed segment was measured to obtain the surface area and volume data. (3) The reconstructed spinal cord, grey matter, bilateral CSTs of rat were solid. In C1 to S4 segments of rat's spinal cord, the CSTs lie in the posterior funiculus and were close to the back of intermediate zone, appearing as gradually narrowing columns.Conclusions: (1) The 3D human spinal cord can be reconstructed with serial sections and used for further inner structure of spinal cord visible research. (2) The paraffin embedding and"hard"locating marks techniques can be used to obtain the images of serial transverse sections of rat's cerival cord segment, to make 3D reconstruction which can be observed and measured randomly. (3) The CSTs in rat's spinal cord can be reconstructed and offer survey data by using serial LFB stained spinal cord sections and computerized 3D reconstruction.