来自双能直线加速器的18兆伏光子束的特性。

Properties of the 18-MV photon beam from a dual energy linear accelerator.

作者信息

Johnson D A, Ikoro N C, Chang C H, Scarbrough E C, Antich P P

机构信息

University of Texas Health Science Center, Department of Radiology, Dallas 75235-9071.

出版信息

Med Phys. 1987 Nov-Dec;14(6):1071-8. doi: 10.1118/1.596118.

DOI:10.1118/1.596118

PMID:3696074

Abstract

The beam characteristics of the 18-MV photon beam of a Varian Clinac 1800 are presented. The clinically relevant parameters of central axis depth dose, tissue-phantom ratios, peak-scatter factors, and relative output factors are discussed and compared to 18-MV beam data previously reported. The nominal beam energy was found to be 18.3 +/- 0.8 MV on the central axis. The beam symmetry and uniformity meet the manufacturer's specifications. The inverse-square law is applicable within 1.4% over the clinically useful range of distances and field sizes. An empirical fit equation for the central axis depth dose is presented.

摘要

介绍了Varian Clinac 1800的18兆伏光子束的射束特性。讨论了中心轴深度剂量、组织-模体比、峰散射因子和相对输出因子等临床相关参数，并与先前报道的18兆伏射束数据进行了比较。发现中心轴上的标称射束能量为18.3±0.8兆伏。射束对称性和均匀性符合制造商的规格。在临床有用的距离和射野尺寸范围内，平方反比定律在1.4%的误差范围内适用。给出了中心轴深度剂量的经验拟合方程。