Strauss G, Hofer M, Korb W, Trantakis C, Winkler D, Burgert O, Schulz T, Dietz A, Meixensberger J, Koulechov K
BMBF-Innovation Center Computer Assisted Surgery (ICCAS).
HNO. 2006 Feb;54(2):78-84. doi: 10.1007/s00106-005-1321-3.
Accuracy represents the outstanding criterion for navigation systems. Surgeons have noticed a great discrepancy between the values from the literature and system specifications on one hand, and intraoperative accuracy on the other. A unitary understanding for the term accuracy does not exist in clinical practice. Furthermore, an incorrect equality for the terms precision and accuracy can be found in the literature. On top of this, clinical accuracy differs from mechanical (technical) accuracy. From a clinical point of view, we had to deal with remarkably many different terms all describing accuracy. This study has the goals of: 1. Defining "accuracy" and related terms, 2. Differentiating between "precision" and "accuracy", 3. Deriving the term "surgical accuracy", 4. Recommending use of the the term "surgical accuracy" for a navigation system. To a great extent, definitions were applied from the International Standardisation Organisation-ISO and the norm from the Deutsches Institut für Normung e.V.-DIN (the German Institute for Standardization). For defining surgical accuracy, the terms reference value, expectation, accuracy and precision are of major interest. Surgical accuracy should indicate the maximum values for the deviation between test results and the reference value (true value) A(max), and additionally indicate precision P(surg). As a basis for measurements, a standardized technical model was used. Coordinates of the model were acquired by CT. To determine statistically and reality relevant results for head surgery, 50 measurements with an accuracy of 50, 75, 100 and 150 mm from the centre of the registration geometry are adequate. In the future, we recommend labeling the system's overall performance with the following specifications: maximum accuracy deviation A(max), precision P and information on the measurement method. This could be displayed on a seal of quality.
准确性是导航系统的首要标准。一方面，外科医生注意到文献中的数值与系统规格之间存在巨大差异，另一方面，术中准确性也存在差异。在临床实践中，对于“准确性”一词不存在统一的理解。此外，在文献中可以发现对“精度”和“准确性”这两个术语的错误等同。除此之外，临床准确性与机械（技术）准确性不同。从临床角度来看，我们不得不处理大量描述准确性的不同术语。本研究的目标是：1. 定义“准确性”及相关术语；2. 区分“精度”和“准确性”；3. 推导“手术准确性”这一术语；4. 建议在导航系统中使用“手术准确性”这一术语。很大程度上，采用了国际标准化组织（ISO）的定义以及德国标准化协会（DIN）的规范。为了定义手术准确性，参考值、期望值、准确性和精度等术语至关重要。手术准确性应表示测试结果与参考值（真值）之间偏差的最大值A(max)，并额外表示精度P(surg)。作为测量的基础，使用了一个标准化的技术模型。通过CT获取模型的坐标。为了确定与头部手术相关的统计学和实际结果，从注册几何中心进行50次精度分别为50毫米（此处原文表述可能有误，推测为5毫米等更合理数值，但按原文翻译）、75毫米、100毫米和150毫米的测量就足够了。未来，我们建议用以下规格标注系统的整体性能：最大准确性偏差A(max)、精度P以及测量方法的信息。这可以显示在质量印章上。
