The possibilities of full-color three-dimensional reconstruction of biological objects by the method of layer-by-layer overlapping: knee joint of a rat

The article has a goal to demonstrate capabilities of layer-by-layer overlapping method for 3D-reconstruction of knee joint. The model object was chosen for this research to provide the base for new methods in diagnostics and treatment of human orthopedic diseases. We used the original technology of high-precision grinding and compared the ability of quantitative analysis of bone and cartilage tissue on 3D models to the capabilities of classical morphometry of histological slices. Obtained digitized images of thin sections (1200-2600 on each of the 8 joints) had a pixel size of 8 x 8 µm, with a vertical step grinding 8 µm. Its software processing allows for the construction of a virtual slice with an offset and slope, required for the adequate visualization of the biological structures. The developed method of high-precision grinding allows obtaining series of digitized cross-sectional images of biological objects, so the virtual object created on its base, is almost devoid of spatial deformations and distortions of color. Morphometric analysis of these 3D reconstructions in terms of precision and informativeness is not inferior, and according to some indicators it exceeds the quantitative study of serial histological sections. The reconstruction, obtained using the high-precision grinding, can be used to create virtual museum exhibits, atlases and manuals in various biological sciences, based on morphological approach to the cognition of its objects. Another application of reconstruction is to convert them into virtual simulators on the principles of augmented reality or into the models for 3D printing of physical simulators and working prototypes for medicine, veterinary, animal science and related areas. This will be of most value where an MRI or histological reconstruction did not provide full three-dimensional picture.