Gerbi B J
University of Minnesota, Department of Therapeutic Radiology-Radiation Oncology, Minneapolis 55455.
Med Phys. 1991 Jul-Aug;18(4):724-6. doi: 10.1118/1.596666.
Obtaining accurate %DD values for routine treatment calculations is essential in radiation therapy. Many papers have presented expressions to calculate this or related parameters but these expressions often required that the parameters needed by the equation be determined for each individual treatment unit. This paper presents an expression that calculates %DD values with a mean-square accuracy of approximately 1.0% versus measured values. The expression is applicable to beam energies ranging from Co-60 to 24 MV, field sizes from 4 X 4 to 40 X 40 cm2, and depths from 1 cm deeper than dmax to 30 cm. The only information required by this expression that is machine specific is the ionization ratio.
在放射治疗中，获取用于常规治疗计算的准确%DD值至关重要。许多论文都给出了计算该值或相关参数的表达式，但这些表达式通常要求针对每个单独的治疗单元确定方程所需的参数。本文给出了一个计算%DD值的表达式，其与测量值的均方精度约为1.0%。该表达式适用于从钴 - 60到24兆伏的射线能量、4×4至40×40平方厘米的射野尺寸以及比最大剂量深度深1厘米至30厘米的深度范围。该表达式唯一需要的特定于机器的信息是电离比。
