The aim of this step is to match the radiation treatment as precisely as possible to the contour of the lesion. Inclusion of adjacent normal tissue would lead to side-effects and complications, whereas omission of part of the lesion reduces efficacy. The precision of this step is measured not only by the precision of hitting the target point but also by the degree of matching to the contour. The most refined indices of radiation conformity take into account both the amount of target, e.g. tumor, not receiving sufficient radiation dose and the proportion of normal tissue outside the target that would be needlessly irradiated . These indices show a superiority of gamma knife planning to the alternative with a Linac .
In addition to matching the shape, particular care is taken to avoid passing the radiation beams through eloquent structures adjacent to the lesion or even at a distance (e.g. the lens in the eye). This is achieved by plugging some of the radiation sources in the gamma knife and choosing the entry of the beams in linear accelerator techniques.
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The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.