Method for estimating a total scatter factor in dose calculation for radiotherapy

A computer-implemented method for estimating a total scatter factor in dose calculation for radiotherapy, wherein a linear accelerator (LINAC) is used to irradiate a medium, the method comprising:

• receiving geometric data of the LINAC, wherein the geometric data comprises geometric information about a LINAC head of the LINAC, wherein the LINAC head comprises at least one collimating device and at least one irradiation source;
• determining a head scatter factor based on a geometric head model using the received geometric data, wherein the head scatter factor quantifies a scatter contribution from the LINAC head, wherein the geometric head model further comprises adjustable fit head parameters and fixed head parameters, depending on a configuration of the LINAC and a measurement setup of the LINAC;
• determining a phantom scatter factor based on an empiric phantom scatter formula using the received geometric data, wherein the phantom scatter factor quantifies a scatter contribution from the irradiated medium;
• and
• determining an estimated total scatter factor using the determined head scatter factor and the determined phantom scatter factor.

A non-transitory computer readable medium storing instructions, which when executed by a computer, causes the computer to perform a computer-implemented method for estimating a total scatter factor in dose calculation for radiotherapy, wherein a linear accelerator (LINAC) is used to irradiate a medium, the method comprising:

• receiving geometric data of the LINAC, wherein the geometric data comprises geometric information about a LINAC head of the LINAC, wherein the LINAC head comprises at least one collimating device and at least one irradiation source;
• determining a head scatter factor based on a geometric head model using the received geometric data, wherein the head scatter factor quantifies a scatter contribution from the LINAC head, wherein the geometric head model further comprises adjustable fit head parameters and fixed head parameters, depending on a configuration of the LINAC and a measurement setup of the LINAC;
• determining a phantom scatter factor based on an empiric phantom scatter formula using the received geometric data, wherein the phantom scatter factor quantifies a scatter contribution from the irradiated medium;
• and
• determining an estimated total scatter factor using the determined head scatter factor and the determined phantom scatter factor.

A non-transitory computer readable medium storing instructions, which when executed by a computer, causes the computer to perform a computer-implemented method for estimating a total scatter factor in dose calculation for radiotherapy, wherein a linear accelerator (LINAC) is used to irradiate a medium, the method comprising:

• receiving geometric data of the LINAC, wherein the geometric data comprises geometric information about a LINAC head of the LINAC, wherein the LINAC head comprises at least one collimating device and at least one irradiation source, wherein the at least one collimating device comprises at least one multi leaf collimator (MLC) defining an MLC plane perpendicular to an irradiation direction of the LINAC, and jaws defining a jaw plane perpendicular to the irradiation direction of the LINAC, wherein the geometric data of the LINAC comprises leaf positions of leaves of the MLC and a jaw position of the jaws;
• determining a head scatter factor based on a geometric head model using the geometric data, wherein the head scatter factor quantifies a scatter contribution from the LINAC head;
• determining a phantom scatter factor based on an empiric phantom scatter formula using the geometric data, wherein the phantom scatter factor quantifies a scatter contribution from the medium;
• determining an estimated total scatter factor using the head scatter factor and the phantom scatter factor;
• determining at least one MLC opening in the MLC using the leaf positions;
• determining, for each MLC opening, a rectangular equivalent field using the leaf positions;
• determining, for each MLC opening, the head scatter factor based on the geometric head model using the rectangular equivalent field and the jaw position;
• and
• determining, for each MLC opening, the phantom scatter factor based on the empiric phantom scatter formula using the rectangular equivalent field and the jaw position.