[A monitor unit verification calculation independent on RTP systems and output factor]

In order to confirm quality assurance and quality control in radiation therapy, it is common to perform a monitor unit verification calculation independent on RTP system. Generally, this verification calculation is often to perform at manual calculation level separately from RTP system. Characteristics of output factors included in this calculation were explained on the basis of the situation in the world. Khan et al. had proposed the concept of collimator scatter factor and phantom scatter factor. The validity of these factors was addressed in of role played in dose monitor unit calculation. If we will utilize SMR, which was derived from zero-area phantom scatter factor, and zero-area TMR in dosimetry, a simple and accurate Clarkson integration is possible. These scatter factors and Clarkson integration is able to use not only for monitor unit calculation in a simple treatment technique, but also in an excellent technique as IMRT. These factors had been also used in the convolution method to improve an accuracy of dose calculation. These factors are not family in Japan, but it is expected to be got an agreement of the usage in future.