Drerup Burkhard
Bundesfachschule für Orthopaedietechnik, Schliepstrasse 6-8, Dortmund, Germany.
Scoliosis. 2014 Dec 12;9(1):22. doi: 10.1186/s13013-014-0022-7. eCollection 2014.
Back surface topography has gained acceptance in recent decades. At the same time, the motivation to use this technique has increased. From the view of the patient, the cosmetic aspect has played and still plays a major role as it provides a comprehensive documentation of cosmetic impairment. From the view of the medical practitioner, the aspect of reducing X-ray exposures in diagnosis and follow-up has been dominant and still prevails. Meanwhile, new aspects have emerged: due to the consequent three-dimensional view of the scoliotic condition, treatment success can be visualized convincingly. Clinical diagnosis is supported by information otherwise not supplied by X-rays, such as when functional examinations and diagnostic tests are recorded.
Like rasterstereography, most techniques of actual back surface measurement refer to photogrammetry and the triangulation method. However, with respect to the particular clinical application, a wide spectrum of implementations exists. Applications in a clinic require high accuracy of measurement in a short time and comprehensive analysis providing data to be used to supplement and compare with radiographic data. This is exemplified by rasterstereography; the procedures of surface analysis and localization of landmarks using curvatures and the reconstruction of the spinal midline will be described.
Based on rasterstereographic analysis, different geometrical measures that characterize the back surface are given and underlying skeletal structures described. Furthermore, in analogy to radiological projection, a 3-D reconstruction of the spinal midline is visualized by a frontal and lateral projection, allowing comparison with pertinent X-rays.
Surface topography and, in particular, rasterstereography provide reliable and consistent results that may be used to reduce X-ray exposure. Unfortunately, the correlation of shape parameters with the radiological Cobb angle is poor. However, the wealth of additional applications substantially enhances the spectrum of clinical value.
近几十年来，背部表面形貌测量技术已被广泛接受。与此同时，使用该技术的动机也在增加。从患者的角度来看，美容方面一直并仍然起着重要作用，因为它能全面记录美容损伤情况。从医生的角度来看，减少诊断和随访过程中的X射线照射这一方面一直占据主导地位且仍然很重要。与此同时，新的方面也出现了：由于对脊柱侧弯情况的三维直观视图，治疗效果能够令人信服地显现出来。功能检查和诊断测试记录等X射线无法提供的信息也有助于支持临床诊断。
与光栅立体摄影术一样，大多数实际背部表面测量技术都涉及摄影测量法和三角测量法。然而，就特定的临床应用而言，存在多种实现方式。临床应用需要在短时间内进行高精度测量，并进行全面分析以提供用于补充和与放射学数据进行比较的数据。光栅立体摄影术就是一个例子；将描述使用曲率进行表面分析和地标定位以及脊柱中线重建的过程。
基于光栅立体摄影分析，给出了表征背部表面的不同几何测量方法，并描述了其下方的骨骼结构。此外，类似于放射学投影，通过前后位和侧位投影可视化脊柱中线的三维重建，以便与相关的X射线进行比较。
表面形貌测量，尤其是光栅立体摄影术，能提供可靠且一致的结果，可用于减少X射线照射。遗憾的是，形状参数与放射学Cobb角的相关性较差。然而，大量的其他应用显著提高了临床价值的范围。
