激光扫描面部软组织三维数字化图像定点准确性和可重复性的研究

目的 评价操作者在面部软组织数字化模型上进行虚拟定点的准确性和一致性.方法 3名操作者,使用在电脑屏幕上对面部软组织数字化模型虚拟定点,以及在受试者面部实体定点两种方法,分别对20名受试者的面部软组织标志点进行定点.通过比较两种方法定点结果的一致性,以及不同操作者定点之间的一致性,评价在激光扫描所得面部软组织数字化模型上虚拟定点的准确性和一致性.结果 不同操作者之间的一致性检验表明,左右侧颧突点、左右侧眶下点、左侧鼻翼点和左右侧下颌角点的一致性小于0.9;数字化模型定点和实体定点相比,眉间点、鼻根点、鼻尖点、上唇突点和下唇突点,3名操作者两种定点方法之间差异的平均值≤2mm;左右侧鼻翼点,左右侧耳点和颏唇沟点,3名操作者两种定点方法之间差异的平均值>2mm且≤3mm;颏前点,左右侧颧突点,左右侧眶下点和左右侧下颌角点,3名操作者两种定点方法之间差异的平均值>3mm.结论 在面部软组织数字化模型上进行虚拟定点时,对于颏前点,左右侧颧突点,左右侧眶下点和左右侧下颌角点,建议使用标记物辅助定位后,再进行扫描及测量.

Accuracy and repeatability of facial soft tissue landmarks on 3D laser-scanned facial images

Objective To assess the accuracy and repeatability of facial soft tissue landmarks on 3D laser-scanned facial images. Methods The facial landmarks of 20 volunteers were assessed. The 3D facial images were acquired for each subject using Minolta laser scanners. Seventeen facial landmarks were identified and recorded on each 3D facial image by 3 operators. The repeatability of landmarks identification was assessed between different operators. In addition,by comparing with the landmarks on volunteers' face,the accuracy of landmarks on 3D facial images was assessed. Results Repeatability of 7 landmarks was not high and the interclass correlation coefficiency (ICC) was lower than 0.9. They were right/left zygomatic point,right/left orbitale,left nasal ala and right/left gonion. The accuracy of the glabella, nasion, pronasale, upper/lower lip prominent was good (≤2mm). The accuracy of right/left nasal ala, right/left tragion and mentolabial sulcus was moderate (2mm3mm). Conclusions It is suggested that the marker should be used for auxiliary location before scanning to assure the accuracy and repeatability of these landmarks on digital 3D soft tissure models. They are pogonion,right/left zygomatic point,right/left orbitale and right/left gonion.