US-12616853-B2 - Patient-positioning system for radiotherapy

US12616853B2US 12616853 B2US12616853 B2US 12616853B2US-12616853-B2

Abstract

A patient-positioning system for radiotherapy is provided. The system includes a processing device and a storage device. The processing device loads a program from the storage device to execute a control module, a positioning room module, and a treatment room module. The control module obtains treatment planning data. The positioning room module calculates the second support displacement of the fulcrum through image registration based on the tilt angle, rotation angle, target displacement, original target point cloud, and a reference displacement. The treatment room module drives the mechanical device to move the treatment room table such that the fulcrum is at the second support displacement relative to the beam exit.

Inventors

Tzung-Yi LIN

Assignees

HERON NEUTRON MEDICAL CORP.

Dates

Publication Date: 20260505
Application Date: 20230612
Priority Date: 20230119

Claims (9)

1 . A patient-positioning system for radiotherapy, comprising a processing device and a storage device, wherein the processing device loads a program from the storage device to execute: a control module, obtaining treatment planning data, wherein the treatment planning data includes a tilt angle, a rotation angle, a target displacement, and an original target point cloud of an irradiation target; a positioning room module, calculating a first support displacement of a fulcrum through image registration based on the tilt angle, the rotation angle, the target displacement, the original target point cloud, and a reference displacement, wherein the first support displacement is a displacement of the fulcrum relative to a beam exit when arrangement of a treatment room table conforms to the treatment planning data, and wherein the treatment room table and a mechanical device are connected at the fulcrum; and a treatment room module, driving the mechanical device to move the treatment room table such that the fulcrum is at the first support displacement relative to the beam exit; wherein when the arrangement of the treatment room table conforms to the treatment planning data, the treatment room table is tilted at the tilt angle and rotated at the rotation angle, and the irradiation target on the treatment room table is at the target displacement relative to the beam exit.
2 . The system as claimed in claim 1 , wherein the positioning room module further executes the following steps: calculating a tilt target point cloud based on the tilt angle and the original target point cloud; obtaining a first captured point cloud of the irradiation target on the positioning room table, wherein the first captured point cloud is captured by a first set of camera devices when the positioning room table is tilted at the tilt angle; determining a first offset by performing image registration on the tilt target point cloud and the first captured point cloud; calculating a second support displacement of the fulcrum based on the first offset, the target displacement, and the reference displacement, wherein the second support displacement is the displacement of the fulcrum relative to the beam exit when the treatment room table is tilted at the tilt angle but not rotated; and calculating the first support displacement based on the rotation angle and the second support displacement.
3 . The system as claimed in claim 2 , wherein the treatment room module further executes the following steps: driving the mechanical device to move the treatment room table such that the fulcrum is at the second support displacement relative to the beam exit; obtaining a second captured point cloud of the irradiation target on the treatment room table, wherein the second captured point cloud is captured by a second set of camera devices when the treatment room table is tilted at the tilt angle; determining a second offset by performing image registration on the tilt target point cloud and the second captured point cloud; and correcting the first support displacement based on the rotation angle and the second offset.
4 . The system as claimed in claim 3 , wherein the treatment room module further executes the following steps: obtaining a fourth captured point cloud of a calibration object on the treatment room table, wherein the fourth captured point cloud is captured by the second set of camera devices; and calibrating parameter settings of the second set of camera devices by performing image registration on the fourth captured point cloud and a calibration object point cloud; wherein a second set of laser emitters are attached to the second set of camera devices; and wherein when the second set of camera devices captures the fourth captured point cloud, laser beams emitted by the second set of laser emitters are aligned with the corresponding marks on the calibration object.
5 . The system as claimed in claim 1 , wherein the positioning room module further executes the following steps: calculating a transformed target point cloud based on the tilt angle, the rotation angle and the original target point cloud; obtaining a third captured point cloud of the irradiation target on the positioning room table, wherein the third captured point cloud is captured by the first set of camera devices when the positioning room table is tilted at the tilt angle and rotated at the rotation angle; determining a third offset by performing image registration on the transformed target point cloud and the third captured point cloud; and calculating the first support displacement based on the third offset, the target displacement, and the reference displacement.
6 . The system as claimed in claim 2 , wherein the positioning room module further executes the following steps: obtaining a fifth camera point cloud of a calibration object on the positioning room table, wherein the fifth camera point cloud is captured by the first set of camera devices; and calibrating parameter settings of the first set of camera devices by performing image registration on the fifth captured point cloud and the calibration object point cloud; wherein a first set of laser emitters are attached to the first set of camera devices; and wherein when the first set of camera devices captures the fifth captured point cloud, laser beams emitted by the first set of laser emitters are aligned with corresponding crosshairs on the calibration object.
7 . The system as claimed in claim 1 , wherein the treatment room module further executes the following steps: driving the mechanical device to move the treatment room table such that the calibration object on the treatment room table is at the target displacement relative to the beam exit; obtaining a third support displacement of the fulcrum relative to the beam exit; and calculating the reference displacement of the fulcrum relative to the calibration object based on the third support displacement and the target displacement.
8 . The system as claimed in claim 1 , wherein the treatment room module further drives an irradiation device to irradiate the irradiation target on the treatment room table.
9 . The system as claimed in claim 5 , wherein the positioning room module further executes the following steps: obtaining a fifth camera point cloud of a calibration object on the positioning room table, wherein the fifth camera point cloud is captured by the first set of camera devices; and calibrating parameter settings of the first set of camera devices by performing image registration on the fifth captured point cloud and the calibration object point cloud; wherein a first set of laser emitters are attached to the first set of camera devices; and wherein when the first set of camera devices captures the fifth captured point cloud, laser beams emitted by the first set of laser emitters are aligned with corresponding crosshairs on the calibration object.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This Application claims priority of Taiwan Patent Application No. 112102560, filed on Jan. 19, 2023, the entirety of which is incorporated by reference herein. BACKGROUND OF THE INVENTION Field of the Invention The present disclosure relates in general to the field of radiotherapy, and it relates in particular to a patient-positioning system for radiotherapy. Description of the Related Art In the field of radiation therapy (which includes procedures such as Boron Neutron Capture Therapy (BNCT)), it may be necessary for patients to be irradiated in various postures. Therefore, the table on which a patient is lying during such radiation therapy can not only be rotated on the horizontal plane, but it can also be tilted in the vertical direction. Currently, patient-positioning systems for radiotherapy use, as input data, computed tomography (CT) images taken of the patient in the supine position before radiotherapy. Based on this, the image monitoring and analysis of the patient's surface characteristics are performed to locate the affected part of the patient (i.e., to learn the relative spatial position of the irradiation target). If the patient needs to be irradiated in other postures, the patient table may have various tilt angles or rotation angles for accurately irradiating the patient, and the position of the patient's affected part (i.e., the irradiation target) will inevitably change relative to the supine posture. However, suitable solutions for positioning patients in various postures are currently lacking. In view of the above problems, there is a need for a patient-positioning system for radiotherapy that takes into account the rotation angle and tilt angle of the patient table, so as to more accurately locate the irradiation target. BRIEF SUMMARY OF THE INVENTION An embodiment of the present disclosure provides a patient-positioning system for radiotherapy. The system includes a processing device and a storage device. The processing device loads a program from the storage device to execute a control module, a positioning room module, and a treatment room module. The control module obtains treatment planning data. The treatment planning data includes the tilt angle, rotation angle, target displacement, and the original target point cloud of an irradiation target. The positioning room module calculates the second support displacement of the fulcrum through image registration based on the tilt angle, rotation angle, target displacement, original target point cloud, and a reference displacement. The second support displacement is the displacement of the fulcrum relative to the beam exit when the arrangement of a treatment room table conforms to the treatment planning data. The treatment room table and a mechanical device are connected at the fulcrum. The treatment room module drives the mechanical device to move the treatment room table such that the fulcrum is at the second support displacement relative to the beam exit. When the arrangement of the treatment room table conforms to the treatment planning data, the treatment room table is tilted at the tilt angle and rotated at the rotation angle, and the irradiation target on the treatment room table is at the target displacement relative to the beam exit. In an embodiment, the positioning room module further calculates a tilt target point cloud based on the tilt angle and the original target point cloud. The positioning room module further obtains a first captured point cloud of the irradiation target on the positioning room table. The first captured point cloud is captured by a first set of camera devices when the positioning room table is tilted at the tilt angle. The positioning room module further determines a first offset by performing image registration on the tilt target point cloud and the first captured point cloud. The positioning room module further calculates the first support displacement of the fulcrum based on the first offset, the target displacement, and the reference displacement. The first support displacement is the displacement of the fulcrum relative to the beam exit when the treatment room table is tilted at the tilt angle but not rotated. The positioning room module further calculates the second support displacement based on the rotation angle and the first support displacement. In an embodiment, the treatment room module further drives the mechanical device to move the treatment room table such that the fulcrum is at the first support displacement relative to the beam exit. The treatment room module further obtains a second captured point cloud of the irradiation target on the treatment room table. The second captured point cloud is captured by a second set of camera devices when the treatment room table is tilted at the tilt angle. The treatment room module further determines a second offset by performing image registration on the tilt target point cloud and the second captured point c