EXTENSION OF THE NET FRACTIONAL DEPTH DOSE FOR INHOMOGENEITY CORRECTION

对身体组织中的不均质性的影响的校正是 在治疗优化中具有相当重要的意义 尤其是胸部区域的病变，如胸骨肿瘤 乳房、食道或肺。CT的问世带来了 让这一切变得有意义。最近描述的NFD是 通过将密度比例概念纳入 场大小以及深度参数，在解析的 恶意，因此包括对不均质性的纠正。这 方法现在包括对辅助 一系列重要条件下的电子传输。进一步 需要做的工作是将电子传输结合起来 波束边缘附近的校正和小的不均匀性 更大的田地。这种方法似乎是准确的、通用的和 易于实施。

The correction for the effect of inhomogeneity in body tissues is of considerable importance in the treatment optimization especially, of lesions in the thoracal region, such as the tumors of the breast, the esophagus, or the lung. The advent of CT has made this meaningful. The recently described NFD has been extended by the incorporation of the density scaling concept in the field size as well as the depth parameter, in the analytical for malism, thus including correction for inhomogeneities. This method now includes correction for the effect of secondary electron transport for a significant set of conditions. Further work needs to be done to incorporate the electron transport correction near the beam edges and for small inhomogeneities in larger fields. The method appears to be accurate, versatile and easy to implement.