<unk>  shape of an X-MLCs A<unk>  <unk>  is a<unk>  or beam-limiting device that is made of individual "leaves" of a high atomic numbered material, usually tungsten, that can move independently in and out of the path of a radiotherapy beam in order to shape it and vary its intensity.<unk> s are used in external beam radiotherapy to provide conformal shaping of beams. Specifically, conformal radiotherapy and Intensity Modulated Radiation Therapy (IMRT) can be delivered using<unk> s. The<unk>  has improved rapidly since its inception and the first use of leaves to shape structures in 1965 to modern day operation and use.<unk> s are now widely used and have become an integral part of any radiotherapy department.<unk> s were primarily used for conformal radiotherapy, and have allowed the cost-effective implementation of conformal treatment with significant time saving, and also have been adapted for use for IMRT treatments. For conformal radiotherapy the<unk>  allows conformal shaping of the beam to match the borders of the target tumour. For intensity modulated treatments the leaves of a<unk>  can be moved across the field to create IMRT distributions <unk> s really provide a fluence modulation rather than intensity modulation). The<unk>  is an important tool for radiation therapy dose delivery. It was originally used as a surrogate for alloy block field shaping and is now widely used for IMRT. As with any tool used in radiotherapy the<unk>  must undergo commissioning and quality assurance. Additional commissioning measurements are completed to model a<unk>  for treatment planning. Various<unk> s are provided by different vendors and they all have unique design features as determined by specifications of design, and these differences are quite significant.
Multileaf collimator
Nuclear technology
Therapy cap
X-ray marker
Cryonics
Hug machine
Radionics
Air ioniser