在本篇論文當中，我們提出了一個新的方法來測量嬰兒頭顱的不對稱性。在獲得頭部的三維影像之後，我們使用特徵質分析用來篩選立體影像中頭部曲率變化較大的部分，並且透過兩階段的K-means分群法將這些部位分群，然後配合各群中心的幾何位置關係，我們將頭部的立體影像旋轉到面對正前方，再運用ICP演算法的精確校正，可以將幼兒頭部立體影像對齊並且校正到一樣的基準。最後，找出一個鏡射平面並產生一個鏡射的頭部影像。我們將此鏡射的頭部影像以及治療後的頭部影像與治療前的頭部影像進行比較，並且計算不對稱度，配合體積的計算與實際的情況比較以證明本論文所提出的方法的可行性。

In this thesis, we propose a new method for measuring the asymmetry measurement of cranium in infants. After obtaining the three-dimensional image of the head, we use the covariance analysis to filter the part of head with larger variation of curvature and a two-phase K-means classification to differentiate those parts. With the help of the geometric relationship of the cluster centers, we can locate the facial organs. Therefore, based on the locations of facial organs, we first rotate the three-dimensional head images to a common frontal orientation and then use the ICP algorithm for the fine registration. All the three-dimensional head images can be aligned to the same benchmark. Finally, we will find a sagittal plan to generate a mirrored head image. We use the head image before treatment compare with the mirrored image and after treatment, and estimating the asymmetric assessment. The experiment results, deformation parts displaying and volume calculating, demonstrate the feasibility of the proposed method.

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