Despite the advantage of using multiple fields to reduce the dose to surrounding healthy tissue, there are still some technical and clinical limitations. What are they?
Some examples are, certain beam angles are prohibited because of the presence of critical organs in those directions. Also, the setup accuracy of a treatment may be better with parallel opposed than with the multiple angled beam arrangement. It is, therefore, important to realize that the acceptability of a treatment plan depends not only on the dose distribution on paper, but also on the practical feasibility, setup accuracy, and reproducibility of the treatment technique.