Diapositive 1

Oncentra/Monaco – Pencil beam and Collapsed

Cone Convolution

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Patient tissue distribution is represented by a 3D density matrix where the

properties in each voxel are either derived from pixel values in a CT image

or from user specified values of mass or electron density.

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It is assumed that the specified density values correspond to tissue material

of “standard” compositions (see ICRP 23 and ICRU 44).

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The Hounsfield number assigned to each standard tissue is mapped from

the calculated electron density using relations given by Knöös et al [38].

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…for charged particle equilibrium conditions CC calculates dose to medium

while PK calculates dose to a large water cavity in medium. Both algorithms

consider attenuation of the beam as per medium

thus;

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Pencil kernel and for point kernel

Dublin 2018

Previously TMS-Helax, Oncentra MasterPlan