X线头影测量分析的误差主要来源于以下三个方面 :头影测量片的质量、定点及测量分析过程。作者对拍摄条件、患者体位、耳杆位置以及投照距离等影响头影测量片质量的因素进行了综述。结论 :高质量的头影测量片是我们正确分析和诊断的前提和基础 ,如何获得影像清晰、定位准确的头影测量片应该受到足够的重视。 X-cephalometry measurement error mainly comes from the following three aspects: Cephalometric film quality, fixed-point and measurement analysis process. The author summarizes the factors that affect the quality of cephalometric films, such as shooting conditions, patient position, ear position and shooting distance. CONCLUSIONS: High quality cephalometric films are the prerequisite and foundation for our correct analysis and diagnosis. How to get a clear and accurate cephalometric film should be given enough attention.