Single-pass imaging and radiation treatment delivery via extended rotating gantry

Abstract

The radiation therapy system delivers radiation treatment in a 360 degree arc in a single pass via an extended rotating gantry and performs a pre-imaging procedure. While rotating the gantry in one direction around the bore of the radiation system, the radiation system generates multiple images of a target volume disposed in the bore using an imaging X-ray source mounted on the gantry. Then, while continuing to rotate the gantry in the same direction, the radiation system delivers a treatment beam to the target volume using a treatment-delivery X-ray source mounted on the gantry, wherein the treatment beam is delivered from some or all of the 360 ​​degree arc around the bore. Thus, the pre-imaging procedure and delivery of radiation are performed in a single pass of the gantry around the target volume, thereby being accomplished without a return trip of the gantry.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 711,483, filed on July 28, 2018, and U.S. Non-Provisional Application No. 16 / 180,021, filed on November 5, 2018. Background Art

[0003] Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.

[0004] Radiation therapy is a localized treatment directed to a specific targeted tissue, such as a cancerous tumor. Ideally, radiation therapy is performed to a planned target volume, which spares surrounding normal tissue from receiving a dose exceeding a specified tolerance, thereby minimizing the risk of damage to healthy tissue. Prior to delivering radiation therapy, an imaging system is typically employed to provide a three-dimensional image of the targeted tissue and surrounding area. From this imaging, the size and mass of the targeted tissue can be estimated, and an appropriate treatment plan generated as well as the target volume determined.

[0005] In order to correctly deliver the prescribed dose to the planned target volume (i.e., target tissue) during radiation therapy, the patient should be correctly positioned relative to the linear accelerator that delivers the radiation therapy. Typically, dose and geometric data are checked before and during treatment to ensure that the patient is correctly positioned and that the radiation therapy treatment administered matches the previously planned treatment. This process is called image-guided radiation therapy (IGRT) and involves viewing the target tissue using an imaging system while the radiation therapy is being delivered to the planned target volume. IGRT incorporates imaging coordinates in the treatment plan to ensure that the patient is correctly aligned for treatment in the radiation therapy device. Summary of the invention

[0006] According to at least some embodiments of the present disclosure, a radiotherapy system is configured to deliver radiation treatment in a 360-degree arc in a single pass via an extended rotating gantry and perform a pre-imaging process. That is, when the gantry is rotated in one direction around the bore of the radiation system, the radiation system generates multiple images of a target volume disposed in the bore using an imaging X-ray source mounted on the gantry. Then, while continuing to rotate the gantry in the same direction, the radiation system delivers a treatment beam to the target volume using a treatment-delivery X-ray source mounted on the gantry, wherein the treatment beam is delivered from some or all of the 360-degree arc around the bore. Thus, the pre-imaging process and delivery of radiation are performed in a single pass on the gantry around the target volume, thereby being completed without the need for a return trip of the gantry.

[0007] The foregoing summary is illustrative only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The foregoing and other features of the present disclosure will become more apparent from the following description and the appended claims in conjunction with the accompanying drawings. These drawings depict only several embodiments according to the present disclosure and therefore should not be considered as limiting the scope thereof. Through the use of the accompanying drawings, the present disclosure will be described with additional specificity and detail.

[0009] Figure 1 is a perspective view of a radiation therapy system according to one or more embodiments of the present disclosure.

[0010] Figure 2A and Figure 2B According to various embodiments of the present disclosure, Figure 1 Schematic perspective view of a radiation therapy system.

[0011] Figure 3 According to various embodiments of the present disclosure, Figure 1 Schematic perspective view of a gantry of a radiation therapy system.

[0012] Figure 4 is a schematic perspective view of a stage mounted on a surface of a drive table according to various embodiments of the present disclosure.

[0013] Figure 5 is another schematic perspective view of a stage mounted on a surface of a drive table according to various embodiments of the present disclosure.

[0014] Fig. 6A Embodiments according to the present disclosure schematically illustrate the routing of flexible utility conduits when the gantry is positioned to one possible degree of rotation of the gantry.

[0015] Figure 6B Embodiments according to the present disclosure schematically illustrate the routing of the flexible utility conduit when the gantry is positioned between the limits of the gantry's clockwise rotation and the limits of the gantry's counterclockwise rotation.

[0016] Figure 6C An embodiment according to the present disclosure schematically illustrates the routing of the flexible utility conduit when the gantry is positioned at the extreme of the counter-clockwise rotation of the gantry.

[0017] Figure 7 The routing of flexible utility pipes proximate to a rack is schematically illustrated according to an embodiment of the present disclosure.

[0018] Figure 8 The routing of flexible utility pipes near a rack according to another embodiment of the present disclosure is schematically illustrated.

[0019] Fig. 9 A flow chart is set forth of an example method for radiation therapy in a radiation therapy system having a gantry with a treatment-delivery X-ray source and an imaging X-ray source mounted thereon, in accordance with one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0020] In the following detailed description, reference is made to the accompanying drawings, which form a part thereof. In the drawings, similar symbols generally identify similar components unless the context indicates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It is readily understood that the various aspects of the disclosure as generally described herein and illustrated in the drawings may be arranged, substituted, combined, and designed in a variety of different configurations, all of which are expressly contemplated and constitute a part of the present disclosure.

[0021] In many radiation therapy systems, volumetric arc therapy (VMAT) treatments are performed by rotating the treatment-delivery X-ray source through a 360-degree arc, so that the treatment beam can be delivered from any angle in the plane of rotation of the X-ray source. Therefore, for such radiation systems, the gantry on which the X-ray source is mounted is typically designed to rotate 360 ​​degrees around the bore of the system. Due to interference from liquid cooling hoses and bulky power cables coupled to the rotating gantry, gantry rotations greater than about 360 degrees are typically limited. As a result, any radiation treatment that requires the gantry to rotate around the bore of the system greater than a single 360-degree arc will take more time and is therefore difficult to complete during a single breath hold. This is because completing such a radiation treatment on a conventional system necessarily involves rotating the gantry through an arc to perform the first portion of the radiation treatment, stopping the rotation of the gantry, performing a return trip by rotating the gantry back to the appropriate starting position, and then completing the radiation treatment by rotating the gantry to perform the final portion of the radiation treatment.

[0022] In image guided radiation therapy (IGRT), two-dimensional and / or three-dimensional imaging is used during the radiation treatment process to improve the accuracy of radiation field placement and reduce the exposure of healthy tissue during the radiation treatment. For example, the planned radiation treatment can be adapted based on the detected intra-fraction motion and patient misalignment that may occur during the radiation treatment process. Ideally, an X-ray image of the treated area is acquired immediately before the delivery of the treatment beam and during the same breath hold as the delivery of the treatment beam to minimize the intra-fraction motion of the treated area. For example, a cone beam computed tomography (CBCT) imaging process can be performed to generate an X-ray image of the treated area. However, CBCT and other pre-imaging processes typically require the gantry to be rotated through an arc of 90 degrees (given multiple X-ray imagers) to 180 degrees (given a single X-ray imager). In addition, the delivery of the treatment beam typically requires an additional 360-degree gantry rotation. As a result, a gantry rotation of much greater than 360 degrees is required to acquire an X-ray image immediately before the delivery of the treatment beam and during the same breath hold. As explained above, in conventional radiology systems, when the gantry is rotated beyond 360 degrees, interference with power cables and liquid cooling hoses typically connected to the gantry may occur, thereby preventing conventional systems from performing such procedures in a single pass or stroke of the gantry.

[0023] In view of the foregoing, there is a need in the art for improved systems and techniques for acquiring X-ray images and delivering treatment beams during a single patient breath hold. According to an embodiment of the present disclosure, a radiation therapy system is configured to deliver radiation treatment throughout a full 360 degree arc and perform a pre-imaging procedure in a single pass via an extended rotating gantry. Figure 1 One such embodiment is illustrated in .

[0024] Figure 1 is a perspective view of a radiation therapy system 100 according to one or more embodiments of the present disclosure. The radiation therapy (RT) system 100 is configured to provide targeted radiosurgery and precision radiation therapy for lesions, tumors, and diseases anywhere in the body where radiation treatment is indicated. As such, the RT system 100 may include one or more of: a linear accelerator (LINAC) that generates a megavolt (MV) treatment beam of high energy X-rays, a kilovolt (kV) X-ray source, an X-ray imager, and in some embodiments, an MV electronic portal imaging device (EPID) (not shown for clarity).

[0025] Typically, the RT system 100 has the capability of megavoltage (MV) and kilovoltage (kV) imaging techniques to enable treatment planners and physicians to make clinical decisions that are best for the patient based on the patient's anatomy. In some cases, the treatment plan may include kV imaging for improved visualization of soft tissue. For example, in some embodiments, the RT system 100 is configured with cone beam computed tomography (CBCT) capability for visualization of soft tissue via kV images.

[0026] The RT system 100 includes one or more touch screens 101, a couch motion control 102, an open hole 103, a base positioning assembly 105, a couch 107 disposed on the base positioning assembly 105, and an image acquisition and processing control computer 106, all of which are disposed within the treatment room. Alternatively, in some embodiments, the image acquisition and processing control computer 106 is located outside the treatment room, such as a control room adjacent to the treatment room. The RT system 100 also includes a remote control console 110, which is disposed outside the treatment room and enables treatment-delivery and patient monitoring from a remote location. In some embodiments, the RT system 100 also includes one or more cameras (not shown) for patient monitoring in the treatment room.

[0027] The base positioning assembly 105 is configured to accurately position the couch 107 with respect to the aperture 103. The motion control 102 includes an input device such as a button and / or a switch that enables a user to operate the base positioning assembly 105 to automatically and accurately position the couch 107 to a predetermined position with respect to the aperture 103. The motion control 102 may also enable a user to manually position the couch 107 to a specific position. Typically, the base positioning assembly 105 is configured to position the patient on the couch 107 so that the patient's target region is at or near the isocenter about which the LINAC, EPID, kV X-ray source, and X-ray imager rotate during RT treatment. The base positioning assembly 105 may be used in conjunction with imaging of the patient's anatomy on the day of treatment to adapt the treatment plan to minimize delivered dose errors caused by intra-fraction motion (which includes changes in the patient's anatomy that may occur between daily patient scans). However, intra-fraction motion may significantly affect the outcome of radiation treatment, which may be more challenging to interpret and may result in overdose and / or underdose to at-risk organs. Intra-fraction motion includes anatomical changes due to periodic motion (such as breathing or heart rhythm) or paroxysmal motion (peristalsis, muscle relaxation, coughing, involuntary movements, etc.) and can only be partially managed in conventional radiation therapy systems. For example, passive fixation techniques such as vacuum lock bags, cradles, arm positioning handles, abdominal compression bars, etc. can be used, but these methods are limited in effectiveness. According to an embodiment of the present disclosure, active motion tracking and compensation for intra-fraction motion is facilitated by performing radiation treatment and pre-image acquisition during a single breath hold in a single pass of an extended rotating gantry. The following is combined with Figure 2A , Figure 2B , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 One such embodiment is described.

[0028] Figure 2A and Figure 2B 1 is a schematic perspective view of an RT system 100 according to various embodiments of the present disclosure. For clarity, various elements of the RT system 100 are not shown in FIG. Figure 2A and Figure 2B103, and includes a rotatable gantry, a system cover, a cooling system, etc. As shown, the RT system 100 includes a drive table 210, a gantry bearing 220 disposed on a surface 201 of the drive table 210 and positioned around the hole 103, and a force coil array 230 disposed on the surface 211. The drive table 210 is a fixed support structure for components of the RT system 100, including the gantry, the cooling system of the RT system 100, a display screen, control electronics, etc. The drive table 210 is placed and / or fixed on a support surface 202 outside the RT system 100, such as the floor of an RT processing facility. The gantry bearing 220 rotatably supports the gantry of the RT system 100, and the force coil array 230 includes a plurality of force coils 231 that rotate the gantry. In some embodiments, the force coils 231 are Figure 1 The image acquisition and processing control computer 106 in the image acquisition and processing control computer 106 controls to cause the rotation of the gantry. Specifically, when the force applying coil 231 is properly excited, it applies a pushing force or a pulling force on the magnet coupled to the gantry.

[0029] Figure 3 300 is a schematic perspective view of a gantry 300 of an RT system 100 according to various embodiments of the present disclosure. The gantry 300 is a rotatable support structure on which a component 340 is mounted. The component 340 includes systems and equipment of the RT system 100 that rotate around the bore 103 during RT processing. The component 340 includes a heating system and / or a motorized system, such as a LINAC, an EPID, a kV X-ray source, and / or an X-ray imager. The gantry 300 includes a plurality of magnets 301, such as permanent magnets, attached to a surface 302 ( Figure 2B ). The magnet 301 and the force coil 231 of the force coil array 230 ( Figure 2B In some embodiments, the gantry 300 further includes a tube management surface 303 on which one or more flexible utility tubes (not shown) are collected or retrieved when the gantry 300 is rotated from one rotational position to another rotational position. In some embodiments, the gantry 300 further includes a gantry flange 304 that prevents the flexible utility tubes collected on the tube management surface 303 from being removed from the tube management surface 303 during the rotation of the gantry 300. Such flexible utility tubes and their interaction with the tube management surface 303 are described below in conjunction with Figure 4 , Figure 5 , Fig. 6A , Figure 6B and Figure 6C to describe.

[0030] Figure 4FIG. 2 is a schematic perspective view of a gantry 300 mounted on the surface 201 of the drive table 210 according to various embodiments of the present disclosure. Figure 2B ) and the pipe management surface 303 (see Figure 3 )exist Figure 4 The gantry 300 is covered by the gantry flange 304. According to an embodiment of the present disclosure, the gantry 300 is configured to continuously rotate in a single direction through an arc significantly greater than 360 degrees, such as 480 degrees, 540 degrees, etc. Therefore, the gantry 300 enables the acquisition of X-ray images and the delivery of treatment beams during a single pass (or stroke) of the gantry 300. As a result, the completion of the acquisition of X-ray images and the subsequent delivery of treatment beams during a single patient breath hold is greatly facilitated.

[0031] Figure 5 FIG. 2 is another schematic perspective view of a stage 300 mounted on the surface 201 of the drive stage 210 according to various embodiments of the present disclosure. Figure 5 In the embodiment shown, the platform flange 304 is not shown, so that the pipe management surface 303 and the annular support structure 501 (solid line) are visible. It is also visible that the guide wheel 502 is mounted on the annular support structure and the flexible utility pipe (not shown for clarity) is coupled to the guide wheel 502.

[0032] Like the gantry 300, the annular support structure 501 is rotatably coupled to the drive table 210 and is configured to rotate around the bore 103 of the RT system 100 during radiation treatment. More specifically, the annular support structure 501 is configured to rotate in the same direction as the gantry 300 rotates around the bore 301, but at half the rotational speed. For example, when the gantry 300 rotates clockwise around the bore 301 at 4 RPM, the annular support structure 501 is configured to rotate clockwise (or counterclockwise) around the bore 301 at 2 RPM. Similarly, when the gantry 300 rotates counterclockwise around the bore 301 at a certain rotational speed, the annular support structure 501 is configured to rotate counterclockwise around the bore 301 at half the rotational speed. In addition, the annular support structure 501 is configured to support the guide wheel 502 and enable it to be rotatably translated. That is, when the annular support structure 501 rotates around the hole 103 , the guide wheel 502 can translate rotatably around the hole 103 .

[0033] The guide wheel 502 is a rotatable pipe management cylinder that is rotatably coupled to the annular support structure 501. The guide wheel 502 is configured to guide the flexible utility pipe 503 (dashed line) from a fixed connection point on the drive table 210 to a fixed connection point on the gantry 300. More specifically, the flexible utility pipe 503 is routed from the fixed connection point on the drive table 210 along the pipe management surface 303 of the gantry 300 around the guide wheel 502 half a circle to the fixed connection point on the gantry 300.

[0034] The flexible utility conduit 503 includes one or more hoses for cooling liquids and / or power cables (RF, AC, DC, etc.). The flexible utility conduit 503 can be a single hose or power cable, or a bundle of multiple hoses and / or power cables. Thus, the flexible utility conduit 503 routes one or more utilities from the drive table 210 to the gantry 300. One end of the flexible utility conduit 503 is coupled to a connector 512 mounted on the drive table 210, which remains stationary during operation of the RT system 100. In addition, the opposite end of the flexible utility conduit 503 is coupled to a connector 522 mounted on the gantry 300, which does not remain stationary during operation of the RT system 100. Instead, the connector 522 is rotatably translated about the bore 103 as the gantry 300 rotates about the bore 103. From Figure 5 As is apparent in the , if the flexible utility conduit 503 is routed directly from the connector 512 to the connector 522, rather than being routed around the guide wheel 502, a rotation of the gantry 300 greater than about 360 degrees may cause scaling of the flexible utility conduit 503 and / or cause interference with the gantry 300. However, according to an embodiment of the present disclosure, the flexible utility conduit 503 is routed from the connector 512 to the connector 522 via the guide wheel 502, which is rotatably translated about the bore 103 as the gantry 300 rotates about the bore 103. As a result, the gantry 300 may be continuously rotated in a single direction through an arc significantly greater than 360 degrees, such as 480 degrees or 540 degrees, without interference from the flexible utility conduit 503. Fig. 6A , Figure 6B and Figure 6C One such embodiment is illustrated in .

[0035] Fig. 6A The routing of the flexible utility conduit 503 when the gantry 300 is radially oriented at one possible degree of rotation of the gantry 300 is schematically illustrated according to an embodiment of the present disclosure. Fig. 6A , the gantry 300 is rotated to the limit of the clockwise rotation of the gantry 300, and the annular support structure 501 is at the limit of the clockwise rotation of the annular support structure 501. As a result, the annular support structure 501 (solid line) is oriented so that the guide wheel 502 (which is mounted on the annular support structure 501) is positioned radially close to the connector 522 (all mounted on the gantry 300). The flexible utility conduit 503 is routed about half a turn around the guide wheel 502. Fig. 6A In the embodiment illustrated in FIG. 1 , when the rack 300 is in Fig. 6AAt the maximum degree of clockwise rotation shown in , the connector 512 mounted on the drive stage 210 is radially (counterclockwise) displaced about 225 degrees from the guide wheel 502. In other embodiments, the connector 512 can be mounted on the drive stage 210 at a position that is radially displaced about 350 degrees relative to the guide wheel 502.

[0036] Figure 6B The routing of the flexible utility conduit 503 when the gantry 300 is positioned between the limit of the clockwise rotation of the gantry 300 and the limit of the counterclockwise rotation of the gantry 300 is schematically illustrated according to an embodiment of the present disclosure. Figure 6B In the test, the rack 300 has been Fig. 6A As a result, the annular support structure 501 (which is configured to rotate in the same direction as the gantry 300 but at half the rotation speed) is oriented so that the guide wheel 502 is radially positioned at the current radial position of the connector 522 (e.g. Figure 6B ) and the original radial position of the connector 522 (as shown Fig. 6A ) approximately halfway between the

[0037] Figure 6C The routing of the flexible utility conduit 503 when the gantry 300 is positioned at the extreme of the counterclockwise rotation of the gantry 300 is schematically illustrated according to an embodiment of the present disclosure. Figure 6C In the test, the rack 300 has been Figure 6B 300 is rotated counterclockwise by an additional 270 degrees and is at the limit of counterclockwise rotation of stage 300. Annular support structure 501 is rotated counterclockwise by an additional 135 degrees and is at the limit of counterclockwise rotation of annular support structure 501. As a result, annular support structure 501 is oriented so that guide wheel 502 (which is mounted on annular support structure 501) is positioned radially close to connector 512 (which is mounted on drive stage 210).

[0038] like Fig. 6A , Figure 6B and Figure 6C, the flexible utility conduit 503 is routed half a turn around the guide wheel 502, and the guide wheel 502 is rotatably displaced in the same direction as the carriage 300 is displaced. Thus, as the carriage 300 rotates during operation, a "rolling-up" effect is achieved with respect to the flexible utility conduit 503. That is, as the carriage 300 is rotated to move the connector 522 toward the connector 512, the slack that would normally occur in the flexible utility conduit 503 is instead pulled against the conduit management surface 303. As a result, the carriage 300 can be rotated in a single direction through an arc greater than 360 degrees and up to approximately 700 degrees without the risk of the slack loop of the flexible utility conduit 503 becoming caught on portions of the carriage 300 or drive table 210, or otherwise interfering with the movement of the carriage 300.

[0039] exist Fig. 6A , Figure 6B and Figure 6C In the embodiment illustrated in FIG. 5 , a single guide wheel 502 is coupled to the annular support structure 501, and a single flexible utility pipe 503 is guided from a fixed connection point on the drive table 210 to a fixed connection point on the gantry 300 via the guide wheel 502. In other embodiments, a plurality of flexible utility pipes are each guided from a corresponding fixed connection point on the drive table 210 to a corresponding fixed connection point on the gantry 300 via a corresponding guide wheel. Therefore, in such an embodiment, a plurality of guide wheels are rotatably mounted on the annular support structure 501.

[0040] In some examples, during rotation of the gantry 300 , different portions of the flexible utility conduit 503 may come into contact with each other. Figure 6B One such example is depicted in , in which a portion of the flexible common conduit 503 extending from the connector 512 contacts a portion of the flexible common conduit 503 disposed on the conduit management surface 303 of the gantry 300. These contacting portions of the flexible common conduit 503 move relative to each other as the conduit management surface 303 rotates past the portion of the flexible common conduit 503 extending from the connector 512. As a result, the surface of the flexible common conduit 503 may be subject to additional wear during use. According to some embodiments of the present disclosure, the RT system 100 includes one or more cable separators to prevent such wear. One such embodiment is Figure 7 is illustrated in and another embodiment is in Figure 8 is exemplified in .

[0041] Figure 7 The routing of the flexible utility conduit 503 near the gantry 300 is schematically illustrated according to an embodiment of the present disclosure. Figure 7, the RT 100 includes one or more separation wheels 701, which are rotatably coupled to the annular support structure 501 as shown. Thus, the separation wheel 701 is positioned between a portion of the flexible utility pipe 503 that is positioned against the pipe management surface 303 and a portion of the flexible utility pipe 503 that leads from the guide wheel 502 to the connector 512. As a result, the flexible utility pipe 503 is subject to less wear during rotation of the gantry 300.

[0042] Figure 8 The routing of the flexible utility pipe 503 near the platform 300 according to another embodiment of the present disclosure is schematically illustrated. Figure 8 In the embodiment illustrated in , the RT 100 includes one or more electromagnets 801, which are fixed to the stationary (non-rotating) surface of the drive stage 210. In addition, the flexible common pipe 803 is configured with one or more ferromagnetic plates 802. As shown, the ferromagnetic plates 802 are coupled to the outer surface 804 of the flexible common pipe 803. In some embodiments, the flexible common pipe 803 is configured with a rectangular cross-section, which facilitates the coupling of the ferromagnetic plates 802 to the outer surface 804. In such an embodiment, a computing device such as the image acquisition and processing control computer 106 can be configured to energize and de-energize the electromagnet 801 with appropriate timing so that a portion of the flexible common pipe 803 leading from the guide wheel 502 to the connector 512 is kept away from a portion of the flexible common pipe 503 placed against the pipe management surface 303.

[0043] Fig. 9 A flow chart of an example method for radiation therapy in a radiation therapy system having a gantry on which a treatment-delivery X-ray source and an imaging X-ray source are mounted according to one or more embodiments of the present disclosure is set forth. The method may include one or more operations, functions, or actions illustrated in one or more of blocks 901 to 911. Although the blocks are illustrated in a sequential order, the blocks may be executed in parallel and / or in an order different from those described herein. Moreover, various blocks may be combined into fewer blocks, divided into additional blocks, and / or eliminated based on the desired implementation. Although combined Figures 1 to 8 The method is described with reference to a system of the present invention, but those skilled in the art will understand that any suitably configured radiation therapy system is within the scope of the present disclosure.

[0044] The method 900 begins at step 901, in which a computing device associated with the RT system 100 (such as the image acquisition and processing control computer 106) causes the gantry 300 to rotationally accelerate from a no rotation speed to a target rotation speed about the bore 103 while rotating in a particular direction (e.g., clockwise or counterclockwise). In some embodiments, step 901 is synchronized with or initiated in response to the start of a patient breath hold. In step 901, the gantry begins to rotationally accelerate from a starting position, such as a radial position, which is close to one possible degree of rotation of the gantry 300. The acceleration may be constant or may be variable, such as an S-curve acceleration profile for reducing or eliminating shock when the target acceleration or deceleration is reached. Generally, the rotational acceleration of the gantry 300 ends when the target rotation speed is achieved by the gantry 300 and / or the gantry 300 reaches a certain rotation position (such as an imaging position). In some embodiments, the target rotation speed is reached after the gantry 300 rotates 5 to 20 degrees.

[0045] In step 902, while the gantry 300 continues to rotate in the same direction of rotational acceleration as described in step 901 from the imaging position to the treatment position, the computing device causes a plurality of images of a target volume disposed in the bore 103 to be generated using the imaging x-ray source of the RT system 100. For example, in some embodiments, the target volume is a region surrounding and including a particular target tissue (the planning target volume) such as a cancerous tumor. In some embodiments, the generated images are projection images of the planning target volume. In some embodiments, the treatment position is at least about a quarter rotation of the gantry 300 or 90 degrees from the first position in the current rotational direction of the gantry 300.

[0046] In step 903, the computing device determines whether the current delivery of the treatment beam should be modified based on the multiple images of the planning target volume generated in step 902. In some embodiments, the current position of the planning target volume can be determined based on the multiple images, such as by performing digital tomosynthesis on the projection images generated in step 902. The current position can then be compared to the predicted position of the planning target volume, and the position error of the planning target volume is quantified. If the computing device determines that the current delivery of the treatment beam should be modified, the method 900 proceeds to step 911; if not, the method 900 proceeds to step 904. In some embodiments, the modification of the treatment beam includes suspending the current treatment under certain conditions.

[0047] In step 904, the computing device causes the gantry 300 to continue rotating through the treatment position and causes delivery of the treatment beam to the planned target volume to be initiated by the treatment-delivery x-ray source of the RT system 100. In some embodiments, the computing device then causes the treatment to continue to be delivered until the gantry 300 has completed a full circle, i.e., a 360 degree arc from the treatment position to the treatment position. In embodiments where the delivery of the treatment beam has been modified (see step 911), the computing device causes the modified treatment to be implemented in step 904. In yet another embodiment, the kV imaging process is interleaved with the delivery of the treatment beam, and the image is continuously updated as the treatment arc progresses, thereby checking whether the planned target volume has not moved during the current breath hold. In such an embodiment, the computing device turns off the treatment beam when it has been determined that the planned target volume has moved beyond a threshold displacement. It is noted that imaging, not just delivery of the treatment beam, may also occur after the gantry 300 has rotated through the treatment position.

[0048] In step 905, after the gantry 300 has completed a turn from the processing position to the processing position, the computing device rotationally decelerates the gantry 300 from the target rotational speed to the no-rotation speed. The deceleration occurs while the gantry 300 rotates from the processing position to the stop position in the current rotational direction. In some embodiments, the stop position is radially proximate to another possible degree of rotation of the gantry 300. In some embodiments, the no-rotation speed is reached from the target rotational speed after the gantry 300 rotates 5 to 20 degrees.

[0049] In step 906, after rotationally decelerating the gantry 300 from the target rotation speed to the non-rotation speed, the gantry 300 rotates to the starting position in a second direction opposite to the specific direction. That is, the computing device rotates the gantry 300 back to the starting position described in step 901.

[0050] In step 911, which is performed in response to the computing device determining that the treatment beam should be modified, the computing device determines a modified delivery of the treatment beam, or aborts the attempt and requires the patient to restart the breath hold with a different amount of air. In some embodiments, the modified delivery is based on the image generated in step 902.

[0051] Implementation of method 900 as described above enables radiation treatment and pre-image acquisition in a single pass of an extended rotating gantry. Such radiation treatment can be more easily performed during a single breath hold for the patient, thereby maximizing the number of patients who can undergo radiation treatment.

[0052] The description of the various embodiments has been presented for purposes of illustration, but is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

[0053] Aspects of the present embodiment may be embodied as a system, method, or computer program product. Therefore, aspects of the present disclosure may take the form of a complete hardware embodiment, a complete software embodiment (including firmware, resident software, microcode, etc.), or an embodiment incorporating software and hardware aspects that may generally all be referred to herein as "circuits," "modules," or "systems." In addition, aspects of the present disclosure may take the form of a computer program product embodied in (one or more) computer-readable media having computer-readable program code embodied thereon.

[0054] Any combination of one or more computer-readable media may be utilized. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared or semiconductor system, device or apparatus or any suitable combination of the foregoing. More specific examples (non-exhaustive list) of computer-readable storage media would include the following: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any other suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device or apparatus.

[0055] Although various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the appended claims.

Claims

1. A computer program product comprising a computer program which, when executed by a computer, implements a computer-implemented method in a radiotherapy system comprising a gantry having a treatment-delivery X-ray source and an imaging X-ray source mounted thereon, the method comprising: rotating the gantry about the open aperture in a first direction at a first rotational speed and simultaneously rotating the annular support structure about the open aperture at a second rotational speed, wherein the second rotational speed is less than the first rotational speed; generating a plurality of images of a target volume disposed in the open bore using the imaging x-ray source while continuing to rotate the gantry about the open bore in the first direction from a first position to a treatment position; as well as In response to rotating the gantry to the processing position: initiating delivery of a treatment beam to the target volume using the treatment-delivery X-ray source; and The gantry is continued to rotate a complete circle in the first direction to return from the processing position to the treatment position.

2. The computer program product of claim 1, wherein the processing position is separated from the first position in the first direction by at least one quarter rotation of the gantry.

3. The computer program product of claim 1 , further comprising: The stage is rotationally accelerated from a non-rotational speed to a target rotational speed before rotating the stage in the first direction from the first position to the processing position and while rotating the stage in the first direction from a starting position to the first position.

4. The computer program product of claim 3, further comprising: After continuing to rotate the gantry the full revolution in the first direction from the processing position to the processing position and while rotating the gantry in the first direction from the processing position to the stop position, the gantry is rotationally decelerated from the target rotational speed to a no rotational speed.

5. The computer program product of claim 4, further comprising: After rotationally decelerating the gantry from the target rotational speed to a non-rotational speed, the gantry is rotated in a second direction to the starting position. The computer program product of claim 5 , wherein the first direction is opposite to the second direction.

7. The computer program product of claim 1, wherein creating the plurality of images of the target volume comprises rotating the gantry at least a quarter turn.

8. The computer program product of claim 1, wherein the plurality of images of the target volume comprise X-ray projection images.

9. The computer program product of claim 1 , further comprising: determining a modified delivery of the treatment beam to the target volume based on at least a portion of the plurality of images of the target volume; as well as The modified delivery of the treatment beam to the target volume is achieved while continuing to rotate the gantry the complete circle in the first direction from the treatment position to the treatment position.

10. The computer program product of claim 9, wherein the plurality of images of the target volume include x-ray projection images, and wherein determining the modified delivery of the treatment beam to the target volume comprises: Digital tomosynthesis is performed on the projection images to generate a cross-sectional image of the target volume.

11. The computer program product of claim 1 , further comprising: While continuing to rotate the gantry the full circle, imaging of the imaging process is interleaved with delivery of the treatment beam.

12. A radiation processing system comprising: Drive platform; a gantry having a treatment-delivery X-ray source and an imaging X-ray source mounted thereon, wherein the gantry is rotatably coupled to the drive table and is configured to rotate about a bore of the radiation treatment system in a first direction at a first rotational speed; an annular support structure rotatably coupled to the drive stage and configured to rotate about the aperture of the radiation treatment system in the first direction at a second rotational speed when the gantry rotates about the aperture at the first rotational speed, wherein the second rotational speed is half of the first rotational speed; as well as A processor, the processor being configured to: generating a plurality of images of a target volume disposed in the open bore using the imaging x-ray source while rotating the gantry in a first direction about the open bore from a first position to a treatment position; as well as In response to rotating the gantry to the processing position: initiating delivery of a treatment beam to the target volume using the treatment-delivery X-ray source; and The gantry is continued to rotate a complete circle in the first direction to return from the processing position to the treatment position.

13. The radiation treatment system of claim 12, further comprising: a guide wheel rotatably coupled to the annular support structure; as well as A flexible common conduit having a first end and a second end, wherein the first end is coupled to a fixed connection on the drive table, the second end is coupled to a fixed connection on the frame, and the flexible common conduit is routed from the fixed connection on the drive table, around the guide wheel half a circle, to the fixed connection on the frame.

14. The radiation processing system of claim 13, wherein the flexible utility conduit is further routed along a conduit management surface on the gantry.

15. The radiation treatment system of claim 12, wherein during generation of the plurality of images, the imaging x-ray source is fixed relative to the treatment-transfer x-ray source.

16. The radiation treatment system of claim 12, wherein the rotation axis of the gantry is parallel to the axis of the aperture.

17. The radiation treatment system of claim 12, wherein the rotation axis of the annular support structure coincides with the rotation axis of the gantry.

18. The radiation treatment system of claim 13, further comprising at least one cable separator rotatably coupled to the annular support structure and configured to separate a first portion of the flexible common conduit from a second portion of the flexible common conduit during rotation of the gantry.

19. The radiation treatment system of claim 13, further comprising at least one electromagnet coupled to the drive stage and configured to, when energized, attract a ferromagnetic plate to separate a first portion of the flexible common conduit from a second portion of the flexible common conduit during rotation of the gantry, wherein the ferromagnetic plate is coupled to the flexible common conduit.

20. The radiation processing system of claim 12, wherein the processor is further configured to: determining a modified delivery of the treatment beam to a target volume based on at least a portion of the plurality of images of the target volume; and The modified delivery of the treatment beam to the target volume is achieved while continuing to rotate the gantry the complete circle in the first direction from the treatment position to the treatment position.

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