Centre for Imaging Sciences, The University of Manchester, Oxford Road, M13 9PT Manchester, United Kingdom.
Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taiwan.
Sci Rep. 2016 Sep 20;6:33581. doi: 10.1038/srep33581.
Cephalometric tracing is a standard analysis tool for orthodontic diagnosis and treatment planning. The aim of this study was to develop and validate a fully automatic landmark annotation (FALA) system for finding cephalometric landmarks in lateral cephalograms and its application to the classification of skeletal malformations. Digital cephalograms of 400 subjects (age range: 7-76 years) were available. All cephalograms had been manually traced by two experienced orthodontists with 19 cephalometric landmarks, and eight clinical parameters had been calculated for each subject. A FALA system to locate the 19 landmarks in lateral cephalograms was developed. The system was evaluated via comparison to the manual tracings, and the automatically located landmarks were used for classification of the clinical parameters. The system achieved an average point-to-point error of 1.2 mm, and 84.7% of landmarks were located within the clinically accepted precision range of 2.0 mm. The automatic landmark localisation performance was within the inter-observer variability between two clinical experts. The automatic classification achieved an average classification accuracy of 83.4% which was comparable to an experienced orthodontist. The FALA system rapidly and accurately locates and analyses cephalometric landmarks in lateral cephalograms, and has the potential to significantly improve the clinical work flow in orthodontic treatment.
头影测量描记是正畸诊断和治疗计划的标准分析工具。本研究旨在开发和验证一种用于在侧位头颅片中寻找头影测量标志点的全自动标志点标注（FALA）系统，并将其应用于骨骼畸形的分类。共有 400 名受试者的数字侧位头颅片（年龄范围：7-76 岁）可供使用。所有的头颅片均由两位经验丰富的正畸医生手动描记了 19 个头影测量标志点，并为每位受试者计算了 8 个临床参数。开发了一种用于在侧位头颅片中定位 19 个标志点的 FALA 系统。该系统通过与手动描记进行比较进行了评估，并将自动定位的标志点用于临床参数的分类。该系统的平均点到点误差为 1.2mm，84.7%的标志点位于临床可接受的 2.0mm 精度范围内。自动标志点定位性能在两位临床专家的观察者间变异性内。自动分类的平均分类准确率为 83.4%，与经验丰富的正畸医生相当。FALA 系统可以快速、准确地定位和分析侧位头颅片中的头影测量标志点，有可能显著改善正畸治疗的临床工作流程。
