Leslie W D, Borys A, McDonald D, Dupont J O, Peterdy A E
Section of Nuclear Medicine, University of Manitoba, St. Boniface General Hospital, Winnipeg, Canada.
Eur J Nucl Med. 1995 Apr;22(4):351-5. doi: 10.1007/BF00941853.
Accurate reorientation of brain single-photon emission tomography (SPET) is required for quantitative procedures and for correlation with other imaging modalities. Traditionally, brain SPET has utilized reoriented slices parallel to the orbitomeatal line (OML). Reorientation using internal landmarks would be more convenient but has not been systematically compared with the use of external landmarks. We compared the interobserver reproducibility for defining the sagittal and coronal angular deviations using internal landmarks, a visual method based upon external reference markers, and an automated method based upon external reference markers. Internal landmarks were inaccurate for defining the OML whether this was based upon the frontal-occipital or frontal-cerebellar plane. External reference markers resulted in significantly lower interobserver differences for both sagittal and coronal reorientation. An operator-independent implementation proved to be feasible and provided an objective measure of marker coplanarity. In summary, external reference markers should be used when reproducible reorientation and ROI placement are required.
脑单光子发射断层扫描（SPET）的准确定向对于定量程序以及与其他成像模态的相关性而言是必需的。传统上，脑SPET一直使用与眶耳线（OML）平行的重定向切片。利用内部标志物进行重定向会更加方便，但尚未与使用外部标志物进行系统比较。我们比较了使用内部标志物、基于外部参考标记的视觉方法以及基于外部参考标记的自动方法来定义矢状面和冠状面角度偏差时观察者间的可重复性。无论是基于额枕平面还是额小脑平面，内部标志物在定义OML时都不准确。外部参考标记在矢状面和冠状面重定向方面均导致观察者间差异显著降低。事实证明，独立于操作员的实施方案是可行的，并提供了标记共面性的客观测量方法。总之，当需要可重复的重定向和感兴趣区（ROI）放置时，应使用外部参考标记。
