Abstract
Trauma brain injury and its related diseases are the major health problem around the world. For biomedical purpose, biomedical scientists select the zebrafish as a model organism, and they want to understand the corresponding changes of angiogenesis and vascular remodeling between brain lesion and reconstruction. Thereby they could extrapolate the biomedical correlations from the zebrafish model to the human model to provide an effective treatment for trauma brain injury patients. In this thesis, a three-dimensional image analysis system for quantitative assessment of angiogenesis and vascular remodeling in a closed circulatory system of the zebrafish brain is presented to provide the meaningful information for observation and research by biomedical scientists. The proposed system is composed of three parts such as the proposed automatic positioning scheme, the proposed zebrafish brain vascular extraction scheme and the proposed zebrafish brain vascular analysis scheme to quantify the meaningful angiogenesis information from the three-dimensional confocal imaging sequence of the zebrafish brain vascular system. At first, the proposed system combines the top-hat transformation, high-boost filter and morphological double-thresholding to extract the whole vasculatures and remove the dye effusion and the repeated vasculatures in the consecutive images. Furthermore, the proposed algorithm has integrated the object tracking and detection algorithm with the angiogenesis analysis for tracking every meaningful feature such as the vascular branch points and lengths, and then quantifies these meaningful parameters to provide trend graphs of the angiogenesis and vascular remodeling. According to experimental results, the vascular branch points and lengths extracted by the proposed system can indeed describe the complete information of the whole zebrafish brain vascular system, and the quantitative data provided by the proposed system can imply pertinently the growth trend and the remodeling tend. In conclusion, we provide a new integrated system to enhance the signals of the zebrafish brain vascular system from a three-dimensional original microscopic image sequence, extract its whole vasculatures, analyze its vascular features, quantify its meaningful parameters and utilize the time-lapse images of the zebrafish brain vascular system to generate a visualization video which could help biomedical researchers to effectively assess the neurovascular damage and to track the regenerative healing process.