Ort Rebecca, Metzler Philipp, Kruse Astrid L, Matthews Felix, Zemann Wolfgang, Grätz Klaus W, Luebbers Heinz-Theo
Clinic for Cranio-Maxillofacial Surgery, University Hospital of Zurich, Frauenklinikstrasse 24, 8091 Zurich, Switzerland.
Plast Surg Int. 2012;2012:138090. doi: 10.1155/2012/138090. Epub 2012 Aug 5.
Ample data exists about the high precision of three-dimensional (3D) scanning devices and their data acquisition of the facial surface. However, a question remains regarding which facial landmarks are reliable if identified in 3D images taken under clinical circumstances. Sources of error to be addressed could be technical, user dependent, or patient respectively anatomy related. Based on clinical 3D photos taken with the 3dMDface system, the intra observer repeatability of 27 facial landmarks in six cleft lip (CL) infants and one non-CL infant was evaluated based on a total of over 1,100 measurements. Data acquisition was sometimes challenging but successful in all patients. The mean error was 0.86 mm, with a range of 0.39 mm (Exocanthion) to 2.21 mm (soft gonion). Typically, landmarks provided a small mean error but still showed quite a high variance in measurements, for example, exocanthion from 0.04 mm to 0.93 mm. Vice versa, relatively imprecise landmarks still provide accurate data regarding specific spatial planes. One must be aware of the fact that the degree of precision is dependent on landmarks and spatial planes in question. In clinical investigations, the degree of reliability for landmarks evaluated should be taken into account. Additional reliability can be achieved via multiple measuring.
关于三维(3D)扫描设备的高精度及其对面部表面的数据采集,已有大量数据。然而,对于在临床情况下拍摄的3D图像中识别出的哪些面部标志点是可靠的,仍然存在一个问题。需要解决的误差来源可能分别与技术、用户或患者(解剖结构)相关。基于使用3dMDface系统拍摄的临床3D照片,对6例唇裂(CL)婴儿和1例非唇裂婴儿的27个面部标志点进行了观察者内重复性评估,总共进行了1100多次测量。数据采集有时具有挑战性,但在所有患者中均成功完成。平均误差为0.86毫米,范围从0.39毫米(外眦点)到2.21毫米(软下颌角)。通常,标志点的平均误差较小,但测量结果仍显示出相当高的变异性,例如,外眦点的误差范围为0.04毫米至0.93毫米。反之,相对不精确的标志点在特定空间平面上仍能提供准确的数据。必须意识到精度程度取决于所讨论的标志点和空间平面这一事实。在临床研究中,应考虑所评估标志点的可靠程度。通过多次测量可以实现更高的可靠性。