Meyer J H, VanDeventer G, Graham L S, Thomson J, Thomasson D
J Nucl Med. 1983 Mar;24(3):197-203.
Previous methods for correction of depth used geometric means of simultaneously obtained anterior and posterior counts. The present study compares this method with a new one that uses computations of depth based on peak-to-scatter (P:S) ratios. Six normal volunteers were fed a meal of beef stew, water, and chicken liver that had been labeled in vivo with both In-113m and Tc-99m. Gastric emptying was followed at short intervals with anterior counts of peak and scattered radiation for each nuclide, as well as posteriorly collected peak counts from the gastric ROI. Depth of the nuclides was estimated by the P:S method as well as the older method. Both gave similar results. Errors from septal penetration or scatter proved to be a significantly larger problem than errors from changes in depth.
以往校正深度的方法采用同时获得的前位和后位计数的几何平均值。本研究将该方法与一种基于峰散射（P:S）比值计算深度的新方法进行了比较。六名正常志愿者食用了一顿在体内用铟-113m和锝-99m标记的炖牛肉、水和鸡肝餐。每隔短时间用每个核素的前位峰和散射辐射计数以及从胃感兴趣区（ROI）后位采集的峰计数跟踪胃排空情况。通过P:S方法以及较老的方法估计核素的深度。两者结果相似。与深度变化引起的误差相比，隔室穿透或散射引起的误差被证明是一个明显更大的问题。
