Error control in algorithmic approach to step-and-shoot intensity modulated radiation therapy

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments;
• and
• (c) storing in a storage medium a treatment plan based on the segments of step (b), wherein step (a) comprises determining a tradeoff between machine delivery error and the number of segments into which the plateaus will be partitioned in step (b) and wherein step (b) comprises the following the steps:
• (d) constructing a directed graph based on the plateaus;
• (e) determining a series of minimum cost flows in the directed graph;
• (f) determining a tradeoff between the number of segments and machine delivery errors based on the determined minimum cost flows, and
• (g) extracting the segments from the directed graph based on the tradeoff determined in step (f) to thereby partition the plateaus.

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments;
• and
• (c) storing in a storage medium a treatment plan based on the segments of step (b), wherein step (a) comprises determining a tradeoff between machine delivery error and the number of segments into which the plateaus will be partitioned in step (b), wherein the intensity modulated beam comprises a plurality of z-posts, and wherein step (a) comprises the following steps:
• (d) choosing an intensity level d wherein, 1≦d≦I max, wherein Imax is the maximum intensity level of the intensity modulated beam;
• (e) selecting all z-posts having a height of at least d to form a set of selected z-posts;
• (f) cutting each selected z-post whose height is ≧d at level d to form a plateau of z-posts of height d;
• (g) removing the plateau of z-posts from the intensity modulated beam;
• and
• (h) recursively partitioning any remaining portion of the intensity modulated beam until there is no remaining portion of the intensity modulated beam.

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments;
• and
• (c) storing in a storage medium a treatment plan based on the segments of step (b), wherein step (a) comprises partitioning the intensity modulated beam into a sub-IMB and wherein step (a) comprises determining the tradeoff curve between the number of segments and error for the sub-IMB by the following steps:
• (d) generating a canonical delivery option for each set of field opening endpoints for a plurality of intensity modulated beam columns of the sub-IMB;
• (e) for every two consecutive intensity modulated beam columns, determining a series of minimum cost g-matchings between the canonical delivery options of the intensity modulated beam columns;
• (f) determining the tradeoff curves based on the g-matchings;
• and
• (g) extracting the segments for the sub-IMB based on the matched field openings of the canonical delivery options from the determined g-matchings in an increasing order of consecutive intensity modulated beam columns to thereby partition the sub-IMB.

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments, wherein step (a) comprises determining a tradeoff between machine delivery error and the number of segments into which the plateaus will be partitioned in step (b);
• (c) linking the segments to thereby reduce the number of segments;
• and
• (d) storing in a storage medium a treatment plan based on the linked segments of step (c).

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments, wherein step (a) comprises determining a tradeoff between machine delivery error and the number of segments into which the plateaus will be partitioned in step (b);
• (c) linking the segments to thereby reduce the number of segments;
• and
• (d) storing in a storage medium a treatment plan based on the linked segments of step (c), wherein step (c) further comprises the following steps:
• (e) constructing a directed graph H based on the segments extracted;
• (f) determining a minimum cost g-path cover on the directed graph H;
• (g) extracting the final segments based on the g-path cover on H therefore segmenting the entire intensity modulated beam.

A method comprises the following steps:

• (a) generating a canonical delivery option for each set of field opening endpoints for an intensity modulated beam;
• (b) for every two consecutive intensity modulated beam columns of the intensity modulated beam, determining a series of minimum cost g-matchings between the canonical delivery options of the intensity modulated beam columns;
• (c) determining the tradeoff curves based on the g-matchings;
• (d) extracting the segments for the intensity modulated beam based on the matched field openings of the canonical delivery options from the determined g-matchings in an increasing order of consecutive intensity modulated beam columns to thereby partition the intensity modulate beam;
• and
• (e) storing in a storage medium a treatment plan based on the extracted segments of step (d).

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• and
• (b) partitioning the plateaus into segments;
• and
• (c) implementing a treatment plan based on the segments of step (b), wherein step (a) comprises determining a tradeoff between machine delivery error and the number of segments into which the plateaus will be partitioned in step (b).

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments;
• and
• (c) implementing a treatment plan based on the segments of step (b), wherein step (a) comprises determining a tradeoff between machine delivery error and the number of segments into which the plateaus will be partitioned in step (b) and wherein step (b) comprises the following the steps:
• (d) constructing a directed graph based on the plateaus;
• (e) determining a series of minimum cost flows in the directed graph;
• (f) determining a tradeoff between the number of segments and machine delivery errors based on the determined minimum cost flows, and
• (g) extracting the segments from the directed graph based on the tradeoff determined in step (f) to thereby partition the plateaus.

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments;
• and
• (c) implementing a treatment plan based on the segments of step (b), wherein step (a) comprises determining a tradeoff between machine delivery error and the number of segments into which the plateaus will be partitioned in step (b), wherein the intensity modulated beam comprises a plurality of z-posts, and wherein step (a) comprises the following steps:
• (d) choosing an intensity level d wherein, 1≦d≦Imax, wherein Imax is the maximum intensity level of the intensity modulated beam;
• (e) selecting all z-posts having a height of at least d to form a set of selected z-posts;
• (f) cutting each selected z-post whose height is ≧d at level d to form a plateau of z-posts of height d;
• (g) removing the plateau of z-posts from the intensity modulated beam;
• and
• (h) recursively partitioning any remaining portion of the intensity modulated beam until there is no remaining portion of the intensity modulated beam.

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments;
• and
• (c) implementing a treatment plan based on the segments of step (b), wherein step (a) comprises partitioning the intensity modulated beam into a sub-IMB and wherein step (a) comprises determining the tradeoff curve between the number of segments and error for the sub-IMB by the following steps:
• (d) generating a canonical delivery option for each set of field opening endpoints for a plurality of intensity modulated beam columns of the sub-IMB;
• (e) for every two consecutive intensity modulated beam columns, determining a series of minimum cost g-matchings between the canonical delivery options of the intensity modulated beam columns;
• (f) determining the tradeoff curves based on the g-matchings;
• and
• (g) extracting the segments for the sub-IMB based on the matched field openings of the canonical delivery options from the determined g-matchings in an increasing order of consecutive intensity modulated beam columns to thereby partition the sub-IMB.

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments, wherein step (a) comprises determining a tradeoff between machine delivery error and the number of segments into which the plateaus will be partitioned in step (b);
• (c) linking the segments to thereby reduce the number of segments;
• and
• (d) implementing a treatment plan based on the linked segments of step (c).

A method comprising the following steps:

• (a) recursively partitioning an intensity modulated beam into plateaus;
• (b) partitioning the plateaus into segments, wherein step (a) comprises determining a tradeoff between machine delivery error and the number of segments into which the plateaus will be partitioned in step (b);
• (c) linking the segments to thereby reduce the number of segments;
• and
• (d) implementing a treatment plan based on the linked segments of step (c), wherein step (c) further comprises the following steps:
• (e) constructing a directed graph H based on the segments extracted;
• (f) determining a minimum cost g-path cover on the directed graph H;
• (g) extracting the final segments based on the g-path cover on H therefore segmenting the entire intensity modulated beam.

A method comprises the following steps:

• (a) generating a canonical delivery option for each set of field opening endpoints for an intensity modulated beam;
• (b) for every two consecutive intensity modulated beam columns of the intensity modulated beam, determining a series of minimum cost g-matchings between the canonical delivery options of the intensity modulated beam columns;
• (c) determining the tradeoff curves based on the g-matchings;
• (d) extracting the segments for the intensity modulated beam based on the matched field openings of the canonical delivery options from the determined g-matchings in an increasing order of consecutive intensity modulated beam columns to thereby partition the intensity modulate beam;
• and
• (e) implementing a treatment plan based on the extracted segments of step (d).