X线头影测量人工定点的准确性研究

An investigation of accuracy in traditional landmark identification

目的评价X线头影测量分析中人工定点的准确性。方法 10名口腔正畸医师对同一张X线头颅定位侧位片的 2 9个标志点进行定位获得的数据 ,与对照值进行对比以衡量定点误差的大小。结果 S、Ar、U 1、L1的平均误差小于 1.0mm ,它们均为影像轮廓清晰且容易判定的标志点 ;Po、Mes、Co、Gs的平均误差大于 4.0mm ,这些标志点均为图像轮廓的最突点。结论 人工识别时 ,2 8%的标志点存在显著差异 ,存在显著差异的标志点主要是某一图象轮廓的最突点。

Objective To assess the variation of landmark identification in traditional cephalometric analysis. Methods Ten orthodontists identified 29 landmarks according to the same cephalometric radiograph. The mean error of each landmark were determined then .Results S?Ar?U1?L1 were easy to be identified. The mean error of each was lower than 1.0mm. These landmarks were located in clear area of radiograph. The mean errors of Po?Mes?Co?Gs were larger than 4.0mm. These landmarks were located in the protruding of outline of hard-tissue or soft-tissue. Conclusion There are differences in 28% landmarks in the manual recogition sample. The differences were mainly in the protruding of the outline.