【摘要】 医用电子直线加速器结构的复杂性与放射治疗的精确性是一对矛盾，测量精度的物理师与调整机器的工程师又是一对矛盾，这决定了加速器调整的困难程度。结合笔者多年工作经验，本文介绍了加速器等中心系统调整的方法。

    【关键词】 医用电子直线加速器；等中心指示装置；等中心调整

    [Abstract] It's a contradiction between the complexity of the LINAC structure and the accuracy of radiation therapy.Physicist who measuring the machine and engineer who adjusting the machine are also a pair of contradictory. It determines the difficulty of adjusting a LINAC.Based on years of experience， the article describes a range of methods to adjust the ISO center of a LINAC.

    [Keywords] LINAC； Indicating device of ISO center； ISO center adjustment

    【中图分类号】R-1 【文献标识码】B 【文章编号】1671-8801(2015)03-0214-03

    [前言] 等中心是医用电子直线加速器的机架、准直器、治疗床三者旋转轴在三维空间的相交点 ......