Deliverable navigation for multicriteria step and shoot IMRT treatment planning

TL;DR

This paper proposes a method for efficient deliverable navigation in multi-criteria IMRT planning by segmenting Pareto surface plans and limiting active plans during navigation, reducing complexity.

Contribution

It introduces a practical approach to Pareto surface navigation in IMRT planning that minimizes the number of plans needed for convex combinations, improving deliverability.

Findings

Number of plans needed is much less than the theoretical maximum.

Segmenting Pareto plans enables manageable plan navigation.

Limiting active plans simplifies the final deliverable plan.

Abstract

We consider Pareto surface based multi-criteria optimization for step and shoot IMRT planning. By analyzing two navigation algorithms, we show both theoretically and in practice that the number of plans needed to form convex combinations of plans during navigation can be kept small (much less than the theoretical maximum number needed in general, which is equal to the number of objectives for on-surface Pareto navigation). Therefore a workable approach for directly deliverable navigation in this setting is to segment the underlying Pareto surface plans and then enforce the mild restriction that only a small number of these plans are active at any time during plan navigation, thus limiting the total number of segments used in the final plan.