No-view interfraction treatment target motion management using volumetric imaging

Inventors

Jordan, Petr • Maurer, Jr., Calvin R.

Assignees

Accuray LLC

Abstract

A method of the present disclosure includes identifying, based on a reference image, a full motion range of a target, wherein the full motion range of the target defines a full internal target volume (ITV). The method further includes identifying a non-target object in a motion image or the reference image. The method further includes performing a volumetric alignment of the ITV and the non-target object. The method further includes modifying a non-target to target displacement vector based on the volumetric alignment. The method further includes tracking the target based on the modified non-target to target displacement vector.

Core Innovation

The disclosure addresses radiation treatment target motion management by using volumetric imaging to reduce interfraction baseline shifts and uncertainties. A full motion range of a target is identified based on a four-dimensional (4D) inhale and exhale planning reference image, wherein the full motion range defines a full internal target volume (ITV). A non-target object is identified in a motion image or in the reference image.

A non-target to target displacement vector is determined based on a volumetric alignment of the ITV and the non-target object. The non-target to target displacement vector is defined between a reference point on the non-target object and a center of the target as defined by the reference image, and the displacement vector defines an estimated relative position of the target with respect to the non-target object. The approach relies on volumetric alignment between the ITV and the non-target object.

The same non-target to target displacement vector is applied at the reference point on the non-target object after each of a plurality of non-target object corrections to perform 0-view tracking of the target indirectly without tracking the target directly in the motion image. The target displacement vector is to compensate for gross motion of the target within a treatment fraction. Baseline shift between treatment fractions is compensated for based on the ITV.

Claims Coverage

The independent claims cover a method, a system, and a non-transitory computer readable medium that identify a full internal target volume (ITV) from a 4D inhale and exhale planning reference image, determine a non-target to target displacement vector via volumetric alignment with a non-target object, and perform indirect 0-view tracking by applying the same displacement vector after non-target object corrections, including baseline shift compensation based on the ITV. Across the independent claims, the inventive features are organized around four main functions.

Across the independent claims (method, system, and non-transitory computer readable medium), the core claim scope is directed to determining a non-target to target displacement vector from volumetric alignment of a full ITV (identified from a 4D inhale and exhale planning reference image) with a non-target object, and using that vector to enable indirect 0-view tracking of the target via repeated non-target object corrections, with baseline shift compensated based on the ITV.

Stated Advantages

Documented Applications