颅颌面骨骼三维分析系统的研究

ESTABLISHMENT OF THREEDIMENSIONAL ANALYSIS SYSTEM OF CRANIOFACIAL BONES

本研究采用普通的Ｘ线头颅定位摄片仪，同期分次摄取正、侧位定位片，结合计算机图象处理技术，建立了一套颅颌骨的三维分析系统，在绘出可任意旋转的颅颌骨框图的同时，由计算机完成一系列的距离和角度的测量，从而在定性和定量两方面基本满足了临床医师的要求。本系统的优点在于原始资料获取的费用少、放射剂量小、设备要求低，摒弃了常规手工描绘Ｘ线片的方法，避免了此过程引入的误差；运用以侧位片为基准校正正位片的方法，排除了分次拍摄可能造成的头部位置的不一致；定标技术使重建方法更为简化，缩短了重建时间。本研究为临床颅颌面畸形病例诊断和治疗方案制订提供了一种简单、精确和实用的方法。

From ordinary frontal and lateral cephalometric films, we set up a threedimensional analysis system of craniofacial skeleton by using computer image processing. While drawing the craniofacial skeletogram which can be rotated to any directions, the system also can finish a lot of measurements, such as distances and angles, so it can satisfy the clinician's needs not only quantitatively but also qualitatively. The advantages are as follows:(1)The original records can be acquired by lower radioactive dose, less expeniture and little charge. (2)The coordinates of landmarks are input from xray films directly instead of the films' drafts, so that the introduction of errors is reduced. (3)Since we rectify the frontal films by using the lateral films as criterion, it can eliminate the possible difference of head postions caused by taken two films seperately. (4)The scaling technique makes the reconstruction process simplified and the time shortened. Using this system, we obtain a practical and accurate method which can facilitate the diagnosis and treatment planning of the craniomaxillofacial deformities.