Walton L, Hampshire A, Forster D M, Kemeny A A
Department of Medical Physics and Clinical Engineering, Weston Park Hospital, Sheffield, England.
Neurosurgery. 1996 Jan;38(1):170-6; discussion 176-8. doi: 10.1097/00006123-199601000-00038.
This phantom study assesses the accuracy of stereotactic localization using the Leksell G frame (Elekta Instruments AB, Stockholm, Sweden) with T1-weighted magnetic resonance imaging (Siemens 1.5 T Magnetom; Erlangen, Germany). The coordinates of an array of solid perspex rods were determined and compared with measured values in a series of transverse, coronal, and sagittal images. The maximum absolute errors observed (X = 2.7 mm, Y = 7.0 mm, Z = 8.0 mm) were discouraging. However, the more reasonable mean errors (X = 0.4 mm, Y = 0.7 mm, Z = 1.3 mm) reflect considerable variation in accuracy throughout the volume assessed and limitation of maximum errors to specific areas. We present details of the spatial variation and discuss possible mechanisms for improving accuracy. The overall results are of direct relevance only to the scanner used. These results are, however, an indication of the need to approach with caution stereotactic localization using magnetic resonance imaging and to emphasize the requirement for quality assurance and for a comprehensive study of the scanner's characteristics.
这项体模研究评估了使用Leksell G型框架（瑞典斯德哥尔摩的医科达仪器公司）和T1加权磁共振成像（德国埃尔朗根的西门子1.5T Magnetom）进行立体定向定位的准确性。确定了一系列实心有机玻璃棒的坐标，并在一系列横向、冠状和矢状图像中与测量值进行比较。观察到的最大绝对误差（X = 2.7毫米，Y = 7.0毫米，Z = 8.0毫米）令人沮丧。然而，更合理的平均误差（X = 0.4毫米，Y = 0.7毫米，Z = 1.3毫米）反映了在整个评估体积中准确性存在相当大的差异，并且最大误差局限于特定区域。我们给出了空间变化的细节，并讨论了提高准确性的可能机制。总体结果仅与所使用的扫描仪直接相关。然而，这些结果表明在使用磁共振成像进行立体定向定位时需要谨慎，并强调了质量保证以及对扫描仪特性进行全面研究的必要性。
