Multileaf collimators hold significant potential for furthering efficacy and efficiency of radiotherapy. In
less than a decade, the use of multileaf collimators has become commonplace for beam shaping in
radiotherapy. New modalities such as dynamic arc and IMRT are also rapidly gaining acceptance.
Thus the range of applications is vast and integration within the clinical environment challenging.
Challenges are due in part to significant differences in the design and operation among the
commercially available devices. As a result, procedures for acceptance testing, commissioning and
routine quality assurance of MLC have yet to find a high level of standardization.
This presentation will cover the design characteristics of MLC systems and their integration and
operation with linear accelerators relative to various clinical applications. General requirements for field
shaping applications as well as dynamic delivery will be discussed. Specific differences between the
commercially available MLC and mini-MLC systems will be presented. Finally, MLC-specific quality
assurance procedures will be reviewed.