Method for minimizing the tongue and groove effect in intensity modulated radiation delivery
First Claim
1. A method of providing intensity modulated radiation therapy to a target region wherein the tongue and groove effect is minimized, comprising:
- obtaining a multi-leaf collimator (MLC) sequence from an external leaf-sequencing algorithm; and
modifying the MLC sequence to compensate for the tongue and groove effect, wherein modifications are selected such that mechanical limitations of the MLC are not exceeded and at least one of the following is minimized;
a non-weighted sum of the tongue and groove effects,a weighted sum of the tongue and groove effects using time-dependent weighting,a weighted sum of the tongue and groove effects using position-dependent weighting,a weighted sum of the tongue and groove effects using time- and position-dependent weighting,the tongue and groove effect distribution variance in spatial coordinates, orthe tongue and groove effect distribution variance in temporal coordinates.
2 Assignments
0 Petitions
Accused Products
Abstract
The present invention provides an intensity modulated radiation therapy (IMRT) method for treating a target region that minimizes the tongue and groove effect. By minimizing that effect, striping in the final delivered fluence is reduced, which improves the overall quality of the radiation delivery. In the method, compensating functions Ci(x) are added to leaf coordinates ai(x) and bi(x) for all of the leaf pairs i in a leaf sequence algorithm, where Ci(x) is chosen to match the mechanical limitations of the MLC and to minimize non-weighted or weighted sums of the tongue and groove effects, where the weighting is time-dependent, position-dependent, or time- and position-dependent, or to minimize the total treatment time, changes to the original MLC sequence, or the tongue and groove effect distribution variance in spatial or temporal coordinates.
47 Citations
12 Claims
-
1. A method of providing intensity modulated radiation therapy to a target region wherein the tongue and groove effect is minimized, comprising:
-
obtaining a multi-leaf collimator (MLC) sequence from an external leaf-sequencing algorithm; and modifying the MLC sequence to compensate for the tongue and groove effect, wherein modifications are selected such that mechanical limitations of the MLC are not exceeded and at least one of the following is minimized; a non-weighted sum of the tongue and groove effects, a weighted sum of the tongue and groove effects using time-dependent weighting, a weighted sum of the tongue and groove effects using position-dependent weighting, a weighted sum of the tongue and groove effects using time- and position-dependent weighting, the tongue and groove effect distribution variance in spatial coordinates, or the tongue and groove effect distribution variance in temporal coordinates. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A computer readable medium including a computer program for controlling a multi-leaf collimator (MLC) to provide intensity modulated radiation therapy to a target region wherein the tongue and groove effect is minimized, comprising:
-
software code executable on a computer to; obtain a multi-leaf collimator (MLC) sequence from an external leaf-sequencing algorithm; and modify the MLC sequence to compensate for the tongue and groove effect, wherein modifications are selected such that mechanical limitations of the MLC are not exceeded and at least one of the following is minimized; a non-weighted sum of the tongue and groove effects, a weighted sum of the tongue and groove effects using time-dependent weighting, a weighted sum of the tongue and groove effects using position-dependent weighting, a weighted sum of the tongue and groove effects using time- and position-dependent weighting, the tongue and groove effect distribution variance in spatial coordinates, or the tongue and groove effect distribution variance in temporal coordinates. - View Dependent Claims (11, 12)
-
Specification