Three-Dimension Reconstruction And Visualization Of Rat Cerebal Micro-vessels Based On ODT Image And VTK Technique

The three-dimensional reconstruction and visualization of cerebral blood vessels is aninterdisciplinary research field, which is related to computer graphics, image processing technologyand medical imaging etc. It has fundamental significance and application value in efficacyevaluation of vascular drugs, in the mechanism exploration of cerebral circulation and in the aideddiagnosis of vascular diseases. The main content of this paper is to realize three-dimensionreconstruction and visualization of rat cerebral micro-vessels based on VTK technique.First part work: to realize three-dimensional reconstruction and visualization of rat cerebralmicro-vessels. Details of this part work are as follows:(1) Introduce briefly the technique of VTK and two main methods about 3-D reconstruction ofimage: surface rendering and volume rendering.(2) Original ODT images (including OCT structure chart and optical Doppler rheography) ofrat cerebral vessels were acquired by using ODT imaging system; Images denosing and thresholdpreprocessing on the acquired original two-dimensional image were performed; OCT images andoptical Doppler rheographies were fused after preprocessing.(3) 3-D reconstruction was carried from 3-D volume data. Several surface rending and volumerending algorithms were used to reconstruct the rat cerebral vessels’ODT images, and thereconstruction was processed by Visual studio2008 combined with VTK; Key programs wereprovided and reconstructed 3-D pictures were showed; Reconstructed results by all means wereanalyzed and compared; Man-machine interaction for 3-D reconstructed results was realized so thatwe can perform simple interaction operation like rotation and translation on the reconstructed resultfigures.(4) Realizing the 3-D reconstruction of fused image sequences by combining two parts of ODTimage—OCT and Doppler images to confirm the position and shape of rat cerebral micro-vessels incerebral cortex; Segmenting 3-D volume data after volume data reconstructed; Reconstructed resultof vessels was showed after segmentation.The second part of work is to realize the function of interactive operations for reconstructedimages. Details of this part work are as follows:(1) Realizing the virtual slice function for reconstructed images; Virtual sections were createdby setting the normal vectors and inner point which are used to segment 3-D reconstructed imagesand to obtain the section information; This virtual slice function makes cross-sectional image beingshowed synchronously while segmentation operation being done; Both 3-D reconstructed image and cross-sectional image can be interacted by simple operations of mouse.(2) To realize the function of observing inner information for 3-D reconstructed images. Planesegmentation and cuboid segmentation were used to realize interactive segmenting function of 3-Dreconstructed image in real time. For plane segmenting method, 3-D reconstructed images can becut by any planes which created through setting the cut surface and segmenting direction. Forcuboid segmentation, reconstructed images can be segmented by stretching、zooming、translatingand rotating a controllable cuboid through simple mouse operations.