Determination of a body part position during radiation therapy

摘要

The present invention relates to a data processing method for use in the field of radiation therapy and for determining a position of a treatment body part relative to an actual arrangement of at least one position of a treatment beam issued by a treatment device, the position being called monitoring tissue position and the treatment body part being a soft tissue part of an anatomical structure of a patient; the data processing method being constituted to be performed by a computer and comprising the following steps: ● providing CBCT data describing a three-dimensional CBCT image of the anatomical structure, the three dimensional CBCT image representing the treatment body part and a bony structure in a relative position to each other, called tissue-bone pre-alignment position, at a point in time, called pre-alignment time; ● providing x-ray data describing information on a position of the bony structure, called monitoring bone position, relative to the actual arrangement at a point in, time during treatment, called monitoring time, the monitoring time being after the pre-alignment time; ● determining the monitoring tissue position of the treatment body part relative to the actual arrangement ∘ based on the tissue-bone pre-alignment position represented by the CBCT image data, ∘ based on the information on the monitoring bone position described by the x-ray data, and ∘ based on a predefined relationship between a first relative position between the treatment body part and the bony structure at the pre-alignment time and a second relative position between the treatment body part and the bony structure at the monitoring time.

主权项

1. A data processing method in the field of radiation treatment for determining a monitoring tissue position of a treatment body part relative to an actual arrangement of at least one position of a treatment beam issued by a treatment device, the treatment body part being a soft tissue part of an anatomical structure of a patient, the data processing method being constituted to be performed by a computer and comprising:
providing cone-beam computed tomography (CBCT) data describing a three-dimensional CBCT image of the anatomical structure, the three dimensional CBCT image representing the treatment body part and a bony structure in a relative position to each other, called tissue-bone pre-alignment position, the CBCT image being generated at a point in time, called pre-alignment time, wherein the pre-alignment time is a time at which the patient is placed for alignment with respect to the treatment device and wherein the pre-alignment time is after a planning time at which a pre-image as a basis for planning a relative position between the treatment body part and a planned arrangement of the at least one position of the treatment beam of the treatment device is generated; providing x-ray data describing information on a position of the bony structure, called monitoring bone position, relative to the actual arrangement at a point in time during treatment, called monitoring time, the monitoring time being after the pre-alignment time; and determining the monitoring tissue position of the treatment body part relative to the actual arrangement based on:
the tissue-bone pre-alignment position represented by the CBCT data;the monitoring bone position described by the x-ray data; anda tissue-bone monitoring position which describes a relative position between the treatment body part and the bony structure at the monitoring time, the tissue-bone monitoring position being set based on a predefined function of identity and the tissue-bone pre-alignment position, wherein according to the function of identity the treatment body part performs a positional change which is identical with the positional change of the bony structure.