Inverse radiotherapy planning

Background: In clinical practice it sometimes happens that with currently a vailable conformal radiotherapy techniques no satisfactory dose distributio n can be achieved. In these cases inverse radiotherapy planning and intensi ty modulated radiotherapy may give better solutions. Method: Inverse planning is a technique using a computer program to automat ically achieve a treatment plan which has an optimal merit. This merit may either depend on dose or dose-volume constraints like minimum and maximum d oses in the target region or critical organs: respectively, or biological i ndices like the complication free tumor control rate. As the result of inve rse planning the inhomogeneous intensity fluence of the beams is calculated . These fluence distributions may be generated by beam compensators or mult i-leaf collimation. Results: Clinical studies to prove the advantage of inverse planning are al ready on the way. It has been shown that this technology is safe and that t he dose distributions which can be achieved are superior to conventional me thods. Conclusions: Inverse treatment planning and intensity modulated radiation t herapy will almost certainly come to be the technique of choice for selecte d clinical cases.