Wide angle, pinchless patient positioning cradle for medical imaging system

Abstract

To provide a wide angle, pinchless patient positioning cradle for a medical imaging system.SOLUTION: A patient table for a medical imaging system includes a base. The patient table also includes a cradle configured to support a subject to be imaged and to move bi-directionally relative to the base. The patient table further includes a fixed structure coupled to both the base and the cradle. The cradle is configured to move relative to the fixed structure without a portion of the subject being pinched between the cradle and the fixed structure.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The subject matter disclosed herein relates to imaging systems, and more particularly to a wide-angle pinchless patient positioning cradle for medical imaging systems. [Background technology]

[0002] Non-invasive imaging techniques allow for the acquisition of images of internal structures or features of a patient without invasive procedures on the patient. In particular, such non-invasive imaging techniques utilize various physical principles (such as differential transmission of x-rays through a target volume or reflection of acoustic waves) to acquire data and construct an image or depiction of the observed internal features of the patient.

[0003] For example, in computed tomography (CT) and other x-ray-based imaging techniques, x-ray radiation is emitted and passes through an object of interest (such as a human patient), with a portion of the x-ray radiation impinging on an x-ray detector, and image data is collected. In digital x-ray systems, a photodetector generates a signal representing the amount or intensity of x-ray radiation impinging on a discrete pixel area of an x-ray detection element or sensor. This signal is processed to generate an image, which can be displayed for review. In a CT imaging system, the x-ray detector array includes a series of detector elements or sensors, which generate similar signals from different positions as the gantry housing the x-ray source and x-ray detector array rotates around the patient.

[0004] A patient moves into and out of a bore or opening through the center of a gantry of a CT scanner or other medical imaging system via a patient cradle, which is part of the patient table. In particular, a typical patient table typically includes a long, fixed beam structure (e.g., an extruded beam structure) with side support structures located on either side of the patient support cradle that support the patient support cradle. The long, fixed beam structure has linear motion guide rails attached to it that guide the patient support cradle as it moves into and out of the gantry. This configuration typically leaves a gap between the moving part (e.g., the patient support cradle) and the fixed structure (e.g., the fixed beam structure) open to trapping body parts of the patient. Furthermore, this gap between the side support structures and the patient support cradle is prone to collecting and trapping dirt, foreign objects, patient fluids, and other substances that are difficult to access and therefore difficult to disinfect and clean. Furthermore, the side support structures are typically made of metal, which can be cold and startling to the patient when they come into contact with the metal. Furthermore, the width of the cradle is limited by the need to move the patient onto and off the patient table, as the side support structures are not designed to withstand a single patient point load as the patient steps onto the table. Furthermore, the patient support cradle can cause discomfort to the patient during movement of the patient support cradle (e.g., the patient may overhang). Furthermore, because the patient can see the patient support cradle moving relative to the side support structures, the patient support cradle (and its lower resting surface for accommodating heavier patients) can induce kinesiphobia and / or claustrophobia (which can lead to the patient panicking and grabbing the cradle / support structure, potentially trapping the patient's fingers, hands, or other body parts).Additionally, typical patient support cradles have foam cores (e.g., for deep cradles) that increase the depth and thickness of the cradle, thereby increasing the x-ray dose to the patient due to increased attenuation through the cross section of the cradle's foam core. Additionally, the structural limitations imposed by the presence of side support structures make it difficult to perform radiation therapy procedures using a typical patient table. Summary of the Invention

[0005] Certain embodiments commensurate in scope with the originally claimed subject matter are summarized below. These embodiments are not intended to limit the scope of the claimed subject matter; rather, these embodiments are intended only to provide a brief summary of possible forms of the subject matter. Indeed, the subject matter may encompass a variety of forms that may be similar to or different from the embodiments set forth below.

[0006] In one embodiment, a patient table for a medical imaging system is provided. The patient table includes a base. The patient table also includes a cradle configured to support a subject to be imaged and move in two directions relative to the base. The patient table further includes a stationary structure coupled to both the base and the cradle. The cradle is configured to move relative to the stationary structure without a body part of the subject being sandwiched between the cradle and the stationary structure.

[0007] In another embodiment, a computed tomography (CT) imaging system is provided. The CT imaging system includes a gantry having a bore coupled to an imaging component configured to acquire imaging data of a subject. The CT imaging system also includes a patient table. The patient table includes a base. The patient table further includes a stationary structure coupled to both the base and the cradle. The patient table also includes a cradle that supports the subject to be imaged and is configured to move in two directions relative to the base. The cradle has a first width in a first direction perpendicular to a longitudinal axis of the cradle. The first width is greater than a second width in the first direction of the stationary structure.

[0008] In another embodiment, a patient table for an imaging system is provided. The patient table includes a base. The patient table also includes a cradle configured to support a subject to be imaged and move in two directions relative to the base. The patient table further includes a stationary structure coupled to both the base and the cradle. The cradle includes an upper surface and a lower surface. The cradle includes a first portion and a second portion along a longitudinal axis of the cradle. The first portion is configured to extend beyond the stationary structure, and the second portion is configured to remain above the stationary structure when the first portion extends beyond the stationary structure. The first portion has a first thickness in a first direction between the upper surface and the lower surface relative to the longitudinal axis, and the second portion has a second thickness in the first direction relative to the longitudinal axis. The second thickness is greater than the first thickness. [Brief explanation of the drawings]

[0009] These and other features, aspects, and advantages of the presently disclosed subject matter can be better understood from the following detailed description when read in conjunction with the drawings, in which like characters represent like parts throughout. [Figure 1] 1 is a combined view of a patient beginning to climb onto the cradle of a prior art patient table and a patient climbing onto the cradle of a prior art patient table. FIG. [Figure 2] FIG. 1 is a perspective view of a patient table that can be used with a medical imaging system according to aspects of the present disclosure. [Figure 3] FIG. 3 is a top view of the patient table shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 4] FIG. 3 is an end view of a portion of the patient table shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 5] FIG. 3 is an end view of the cradle of the patient table shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 6] FIG. 3 is a top view of a patient resting in a cradle of the patient table shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 7] FIG. 3 is a perspective view of a cradle of the patient table shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 8] 3 is an end view of a cradle (eg, a cradle having a first width) of the patient table shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 9] 3 is an end view of a cradle (eg, a cradle having a second width) of the patient table shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 10] 3 is a top view of a cradle (eg, a cradle with respective dimensions) of the patient table shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 11] 11 is an end view of the cradle of FIG. 10 and a table with associated values according to an embodiment of the present disclosure. [Figure 12] 3 illustrates a patient beginning to mount in the cradle of the patient table of FIG. 2 according to an embodiment of the present disclosure. [Figure 13] 3 illustrates the patient table of FIG. 2 with a patient in a cradle, according to an embodiment of the present disclosure. [Figure 14] 11 illustrates an analysis of a load case (eg, a patient load case) for the cradle of FIG. 10 according to an embodiment of the present disclosure. [Figure 15] 1 shows the attenuation at various points during CT imaging of a patient using a typical cradle. [Figure 16] 3 illustrates the cradle of the patient table of FIG. 2 relative to the path of x-rays passing through a patient during a scan of the patient, according to an embodiment of the present disclosure. [Figure 17] 3A-3C illustrate attenuation at various points during CT imaging of a patient utilizing the patient table cradle of FIG. 2 in accordance with an embodiment of the present disclosure. [Figure 18] 3 shows a table of results of an analysis of x-ray attenuation for both a typical cradle and the cradle of the patient table shown in FIG. 2, according to an embodiment of the present disclosure. [Figure 19] CT images of both a typical prior art cradle shown in FIG. 1 and a cradle of the present disclosure shown in FIG. 2 are shown. DETAILED DESCRIPTION OF THE INVENTION

[0010] Described below are one or more specific embodiments. These embodiments are an attempt to provide a concise description, and not all features of an actual implementation may be described herein. It should be understood that the development of any actual implementation, like any engineering or design project, requires the execution of numerous implementation-specific decisions to achieve the developer's particular goals (including compliance with system-related and business-related constraints, which may vary from implementation to implementation). Moreover, it should be understood that such a development effort might be complex and time-consuming, but would be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure.

[0011] When introducing elements of various embodiments of the present subject matter, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the element. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements. Furthermore, any numerical examples in the following description are intended to be non-limiting, and therefore, additional numbers, ranges, and percentages are within the scope of the disclosed embodiments.

[0012] Although aspects of the following description are provided in the field of medical imaging, it should be understood that the disclosed technology is not limited to such medical fields. Indeed, examples are provided and described in such medical fields simply because providing real-world examples and applications facilitates explanation. However, the disclosed technology can also be utilized in other fields, such as image reconstruction for non-destructive testing of manufactured parts or goods (i.e., quality control or quality review applications) and / or non-invasive inspection of packages, boxes, luggage, etc. (i.e., security or screening applications). In general, the disclosed technology is useful in any imaging or screening situation, or in image processing or photography, where a reconstruction process is performed on an acquired data set or data type to generate an image or volume.

[0013] The present disclosure provides embodiments of a patient table for a medical imaging system (e.g., a computed tomography (CT) imaging system, a magnetic resonance imaging (MRI) system, a positron emission tomography (PET) imaging system, a single photon emission computed tomography (SPECT) imaging system, a nuclear medicine imaging system, an X-ray imaging system, or any combination thereof), the patient table including a cradle for wide-angle, non-trapped patient positioning and support. The patient table includes a base. In certain embodiments, the base is fixed. In certain embodiments, the base is configured for vertical and / or horizontal movement relative to a floor. The patient table also includes a cradle, the cradle supporting a subject (e.g., a patient) to be imaged and configured for movement in two directions relative to the base. The patient table further includes a stationary structure coupled to both the base and the cradle. The cradle is configured for movement relative to the stationary structure without a body part of the subject being trapped between the cradle and the stationary structure.

[0014] In certain embodiments, the cradle has a first width in a first direction perpendicular to a longitudinal axis (or longitudinal length) of the cradle, the first width being wider than a second width of the first structure in the first direction. In certain embodiments, the cradle is positioned above the stationary structure across the first width. In certain embodiments, the first width is at least 52 centimeters (cm). In certain embodiments, a cross-section of the cradle along the first width includes multiple portions, at least two of which are inclined relative to a central portion of the multiple portions.

[0015] In certain embodiments, the cradle varies in thickness along the longitudinal axis in both a first direction (e.g., a lateral direction or width) and a second direction perpendicular to the first direction (e.g., a direction between the top and bottom surfaces of the cradle). In certain embodiments, the cradle includes a first portion and a second portion along the longitudinal axis. The first portion is configured to extend beyond the stationary structure (e.g., into the bore of the gantry), while the second portion is configured to remain above the stationary structure (e.g., outside the bore of the gantry) when the first portion extends beyond the stationary structure. The first portion has a first thickness in the second direction relative to the longitudinal axis, and the second portion has a second thickness in the second direction relative to the longitudinal axis. The second thickness is thicker than the first thickness.

[0016] In certain embodiments, the cradle is configured to support the weight of a single subject (e.g., a patient), and the subject can both enter and exit the cradle using only the cradle. In certain embodiments, the cradle is configured with a flat surface for engaging the top of a radiation therapy table. In certain embodiments, the cradle does not include a foam core. In certain embodiments, the cradle has lower x-ray attenuation than another cradle that has a foam core. In certain embodiments, the cradle is made of carbon fiber reinforced plastic. In certain embodiments, the cradle is manufactured using a carbon fiber reinforced layup process.

[0017] The disclosed embodiments provide a patient table with a cradle that does not include side support structures to provide a pinchless configuration in which a subject's body parts are not pinched between the cradle and a fixed structure while the cradle is moving relative to the fixed structure. The cradle itself serves as a support structure for positioning the patient on the cradle without the need for side support structures. The disclosed table configuration eliminates the need for additional external supports or structures to hold and position the cradle. The elimination of side support structures and the increased width of the cradle reduce the risk of patients developing kinesiphobia and claustrophobia. The disclosed embodiments further provide a patient table that reduces the risk of patients being surprised by cold sensations. Thus, the disclosed embodiments can increase patient comfort. The disclosed embodiments also provide a patient table with improved ease of cleaning and disinfection, thereby reducing associated repair issues and therefore medical imaging system downtime. The disclosed embodiments further provide a wide cradle with a flat surface for engaging the top of a radiation therapy table. The disclosed embodiments further provide a thin, strong, and cost-effective component (i.e., the cradle) made from carbon fiber reinforced plastic. A simple carbon fiber reinforced plastic lamination process for manufacturing the cradle improves productivity. The disclosed embodiments also include a lower x-ray dose to the patient due to the cradle's low x-ray attenuation, which improves x-ray tube life and overall system throughput.

[0018] FIG. 1 is a combined view of a patient 22 beginning to load onto a cradle 50 of a prior art patient table 40 (e.g., for a CT imaging system) and a patient 22 having loaded onto the cradle 50 of the prior art patient table 40. Prior art patient tables 40 typically include a long, fixed beam structure 42 (e.g., an extruded beam structure) with side support structures 44 positioned on either side of the patient support cradle 50 and supporting the patient support cradle 50. The long, fixed beam structure 42 has linear motion guide rails attached to it that guide the patient support cradle 50 as it moves in and out of the gantry. This configuration typically creates a risk of the patient 22 becoming pinched due to gaps between the moving parts (e.g., the patient support cradle 50) and the fixed structure (e.g., the fixed beam structure 42). Furthermore, this gap between the side support structures 44 and the patient support cradle 50 is prone to collecting and trapping dirt, foreign objects, patient fluids, and other materials that are difficult to reach and therefore difficult to disinfect and clean. Additionally, the side support structures 44 are typically made of metal, which can be cold and startling to the patient 22 when the patient 22 rests on the table 40. Furthermore, the side support structures 44 are not configured to withstand the single point load of the patient 22 as the patient rests on the table 40, and the width of the cradle 50 is limited by the need to move the patient 22 onto and off the patient table 40. Furthermore, the patient support cradle 50 can cause discomfort to the patient (e.g., the patient may be pushed out) during movement of the patient support cradle 50. Furthermore, the patient support cradle (and the underlying resting surface it provides to accommodate heavier patients) may induce kinesiphobia and / or claustrophobia, as the patient can see it moving relative to the side support structures (which may lead to the patient panicking and grabbing the cradle / support structure, which could result in the patient's fingers, hands, or other body parts becoming trapped).Additionally, a typical patient support cradle 50 has a foam core (e.g., if the cradle 50 is deep), which increases the depth and thickness of the cradle 50, thereby increasing the attenuation due to the cross-section of the cradle's foam core and therefore increasing the x-ray dose to the patient 22. Additionally, the structural limitations imposed by the presence of side support structures make it difficult to perform radiation therapy procedures using a typical patient table.

[0019] Although the patient table 46 in this disclosure (see FIGS. 2 and 3 ) is described in the context of a CT imaging system, the patient table 46 may be used in other types of medical imaging systems (e.g., magnetic resonance imaging (MRI), positron emission tomography (PET) imaging systems, single photon emission computed tomography (SPECT) imaging systems, nuclear medicine imaging systems, x-ray imaging systems, etc.). That is, the illustrated example of a CT imaging system 10 is merely one environment in which the described patient table 46 may be implemented. Aspects of the patient table 46 in the following figures are described using a coordinate system having a y-direction (or y-axis), an x-direction (or x-axis), and a z-direction (or z-axis). The coordinate system may be described with reference to a longitudinal axis 49 of the patient table 46 (and floating cradle 50). FIGS. 2 and 3 show alternative views of the patient table 46 of the CT imaging system 10 of FIG. 1 . The patient table 46 includes a base 52. In certain embodiments, base 52 is fixed at a location on the floor of the scan room. In other words, base 52 does not move in the y, x, and z directions. In certain embodiments, base 52 is configured to move in two directions (e.g., by linear motion guide rails) along a path on the floor of the scan room (e.g., a path extending in the x direction or an axial direction). The structure of base 52 may differ from the structure shown in FIGS. 2 and 3.

[0020] The patient table 46 also includes a patient support cradle 50. The cradle 50 is configured to support a subject (e.g., a patient) to be imaged. The cradle 50 is configured to move bidirectionally (as indicated by arrows 62) relative to the base 52 in the x-direction and along the longitudinal axis 49. The cradle 50 includes a first side 64 and a second side 66, both of which extend in the x-direction between a first end 68 (first longitudinal end) and a second end 70 (second longitudinal end). The first end 68 is configured to face the imaging system gantry and to move in and out of the gantry bore. The cradle 50, the first side 64, and the second side 66 have a length 72 in the x-direction (e.g., longitudinal length). As described in more detail below, the cradle has a varying thickness along its longitudinal direction. The cradle 50, first end 68, and second end 70 have a width 74 in the z-direction. In certain embodiments, the width 74 is at least 52 cm. In certain embodiments, the width 74 may be between 42 cm and 56 cm (or wider). In certain embodiments, the width 74 may be 52 cm. In certain embodiments, the width 74 may be 54 cm. In certain embodiments, the width 74 may be 56 cm. The width 74 of the cradle 50 is wide enough (for patients of all sizes) to allow any part of the patient's body to be placed in the cradle 50 without any part of the patient's body extending beyond the cradle 50.

[0021] The patient table 46 further includes a stationary structure 78 coupled to an upper end (e.g., top portion 58) of the base 52. The stationary structure 78 is represented by a dashed line in FIG. 3 . Various roller supports (not shown) associated with the stationary structure 78 allow the cradle to move easily relative to the stationary structure 78. The stationary structure 78 does not move in any direction relative to the upper end of the base 52 or the entire base 52. The entire stationary structure 78 is located below the cradle 50 in the Y direction. The stationary structure 78 includes a first side 80 and a second side 82, both of which extend in the X direction between a first end 84 (first longitudinal end) and a second end 86 (second longitudinal length). The stationary structure 78, the first end 84, and the second end 86 have a width 88 in the z direction.

[0022] The patient table 46 does not include side support structures for the cradle 50. The patient table 46 does not have any additional external supports or structures to hold and position the cradle 50. The width 74 of the cradle 50 is greater than the width 88 of the fixed structure 78. The cradle 50 rests on the fixed structure 78 across the entire width 88. The lack of side support structures on either side of the cradle 50 allows the cradle 50 to move relative to the fixed structure 78 without trapping body parts (e.g., fingers or hands) between the cradle 50 and the fixed structure 78. Furthermore, the width 74 of the cradle (and the absence of any side support structures) prevents the subject from visually observing the stationary and moving table components moving relative to one another while the cradle is moving, thereby eliminating kinesiphobia and claustrophobia.

[0023] The cradle 50 is made of carbon fiber reinforced plastic. In particular, the cradle 50 is manufactured by a layering process of carbon fiber reinforced material (or any composite or radiolucent material). This manufacturing technique provides a cradle at a low cost and increases manufacturability (compared to typical cradles). When a patient places a weight on the cradle, the patient is not surprised by a cold feeling (e.g., because the cradle 50 is not made of metal). In certain embodiments, the cradle 50 does not include a foam core. In certain embodiments, the cradle 50 has lower x-ray attenuation than other cradles that have a foam core. In certain embodiments, the cradle 50 can be thinner and slimmer than typical cradles. As described in more detail below, the cradle 50 is configured to support the weight of a single subject (e.g., a patient) and to allow the subject to both enter and exit the cradle 50 using only the cradle 50. In certain embodiments, a foldable handle structure is positioned adjacent to the cradle 50 to assist the subject in entering and exiting the cradle 50.

[0024] FIG. 4 is an end view of a portion of the patient table 46 shown in FIG. 2 . FIG. 5 is an end view of the cradle 50 of the patient table 46 shown in FIG. 2 . As described above, the cradle 50 is positioned above the fixed structure 78 as shown in FIG. 5 . Additionally, the width 74 of the cradle 50 is greater than the width 88 of the fixed structure 78. In certain embodiments, the width 74 is at least 42 cm. In certain embodiments, the width 74 can be between 42 cm and 56 cm (or greater). In certain embodiments, the width 74 can be 52 cm. In certain embodiments, the width 74 can be 54 cm. In certain embodiments, the width 74 can be 56 cm. As shown in FIGS. 5 and 6 , the width 74 of the cradle 50 is wide enough (for patients of all sizes) to allow any body part of the patient 22 to be placed in the cradle 50 without any body part of the patient 22 extending beyond the cradle 50. In certain embodiments, the width 88 of the fixed structure 78 can be greater than the width 74 of the cradle 50. As shown, the cradle 50 does not include a foam core. In certain embodiments, the cradle 50 may include a foam core. As shown, the patient table 46 does not include side support structures so as to provide a pinchless configuration in which no body part of the patient 22 becomes pinched between the cradle 50 and the fixed structure 78 while the cradle 50 is moving relative to the fixed structure 78.

[0025] As shown in FIGS. 4 and 5 , the profile (or cross-section) of the cradle 50 along the width 74 varies. As shown, the cross-section of the cradle 50 along the width 74 includes multiple sections 90. The cradle 50 along the width 74 can include three or more sections 90. Each section 90 is flat and extends in the X direction. Each section 90 also extends along the longitudinal length 72 (shown in FIG. 7 ) of the cradle 50. As shown, the cradle 50 includes at least five sections 90. The cradle 50 includes a central section 92, a first pair of sections 94 disposed on either side of the central section 92, and a second pair of sections 96 disposed on either side of the central section 92 and the first pair of sections 94. The central section 92 is horizontal. The first pair of sections 94 is angled or tilted relative to the central section 92. The second pair of sections 96 is angled or tilted relative to both the central section 92 and the first pair of sections 94. The slope or angle of the second pair of portions 96 relative to the central portion 92 is greater than the slope or angle of the first pair of portions 94 relative to the central portion 92. In certain embodiments, the cradle 50 can have a smooth curve along the width 74. In certain embodiments, the cradle 50 can have any shape along the width 74. In certain embodiments, the widths of one or more of the plurality of portions 90 can be different from one another in the x-direction. In certain embodiments, the widths of the plurality of portions 90 can be the same. In certain embodiments, as shown in FIG. 4 , each vertical portion 98 (extending in the z-direction) can be located at the outermost portion of each of the pair of portions 96. The vertical portions 98 extend along the longitudinal length 72. The location of the plurality of portions 90 can make the cradle 50 more comfortable for the patient. The flat, horizontal central portion 92 provides a flat surface for engaging the top surface of a radiation therapy table, making the cradle 50 easier to use during radiation therapy scans. As shown, the cradle 50 does not include a foam core. In certain embodiments, the cradle 50 may include a foam core.

[0026] The cradle 50 includes an upper surface 100 and a lower surface 102. A patient is placed on the upper surface 100, with the lower surface 102 facing a stationary structure (see FIG. 4). Along the cross-section of the cradle 50, the cradle 50 and each section 90 has a thickness 104 between the upper surface 100 and the lower surface 102. As explained in more detail below, the thickness 104 varies along the longitudinal length 72 (see FIG. 10). The variation in thickness 104 along the longitudinal length 72, in combination with the variation in the profile or cross-section of the cradle 50, distributes deflections and stresses throughout the cradle 50. The thickness 104 may also vary along the width 74.

[0027] FIG. 8 is an end view of the cradle 50 of the patient table shown in FIG. 2 (e.g., a cradle having a first width). FIG. 9 is an end view of the cradle 50 of the patient table shown in FIG. 2 (e.g., a cradle having a second width). The cradle 50 is as described in FIGS. 4 and 5. In FIG. 8, the width 74 of the cradle 50 is 54 cm (540 millimeters (mm)). In FIG. 9, the width 74 of the cradle 50 is 52 cm (520 mm). In certain embodiments, the width 74 may vary between 420 mm and 560 mm. As shown in both FIGS. 8 and 9, the cradle 50 has a depth 106 in the y-direction. In certain embodiments, the depth 106 may vary. The depth 106 and width 74 of the cradle 50 make the cradle 50 more comfortable for the patient. The cradle 50 of FIG. 8 is a lightweight design that weighs less and has a lower deflection value than cradles that include a foam core.

[0028] FIG. 10 is a top view of the cradle 50 of the patient table shown in FIG. 2 (e.g., the respective dimensions of the cradle are shown). The cradle 50 has the profile of the cradle of FIG. 9. The cradle 50 includes a first side 64 and a second side 66, both of which extend in the X direction between a first end 68 (first longitudinal end) and a second end 70 (second longitudinal end). The first end 68 is configured to face the gantry of the imaging system and is configured to move in and out of the gantry bore. The second end 70 (i.e., the fixed end) remains outside the gantry bore and above a fixed structure (e.g., the fixed structure 78 of FIG. 2) when the first end 68 is disposed in the gantry bore. The cradle 50, first side 64, and second side 66 have a length 72 in the X-direction (e.g., longitudinal length). In certain embodiments, the length 72 may vary. The cradle 50, first end 68, and second end 70 have a width 74 in the z-direction. In certain embodiments, the width 74 is at least 42 cm. In certain embodiments, the width 74 can have a length ranging between 42 cm and 56 cm (or greater).

[0029] The cradle 50 varies in thickness (e.g., thickness 104 in FIG. 4 ) along the longitudinal axis 49 (and longitudinal length 72). The cradle 50 includes a first portion 108 (portion A) and a second portion 110 (portion B). A dashed line 112 indicates the boundary between the first portion 108 and the second portion 110. The first portion 108 is associated with the second end 70. The second portion 110 is associated with the first end 68. The first portion 108 has a length 114. The second portion 110 has a length 116. As shown, the length 116 of the second portion 110 is longer than the length 114 of the first portion 108. The lengths 114, 116 of the portions 108, 110 may be different lengths. The length 116 of the second portion 110 is longer than the length 114 of the first portion 108. As shown, the ratio of length 116 to length 114 is slightly less than 2 to 1. In certain embodiments, the ratio of length 116 to length 114 may be other. The thickness of first portion 108 (e.g., thickness 104 in FIG. 4 ) is greater than the thickness of second portion 110 (e.g., thickness 104 in FIG. 4 ). As shown, first portion 108 is 5 mm thick. As shown, second portion 110 is 4 mm thick. First portion 108 is considered a reinforced portion because of its thickness. Second portion 110 is considered a non-reinforced portion. The thicknesses of first portion 108 and second portion 110 may be different. In certain embodiments, first portion 108 and second portion 110 may have the same thickness. In certain embodiments, the thickness of first portion 108 and second portion 110 may vary along width 74 in addition to varying along longitudinal length 72.

[0030] The variation in thickness 104 along the longitudinal length 72, in combination with the variation in the profile or cross section of the cradle 50, distributes deflections and stresses throughout the cradle 50. FIG. 11 shows an end view of the cradle 50 of FIG. 10 and a table 118 with associated values. As shown in table 118, the reinforced portion (e.g., first portion 108 of FIG. 10) has a thickness of 5 mm. The unreinforced portion (e.g., second portion 110 of FIG. 10) has a thickness of 4 mm. The reinforced portion has a thickness of 1.49×10 6 The unreinforced portion has a moment of inertia (MOI) of 1.41 x 10 6 The cradle 50 has a moment of inertia of 15.4 mm. Overall, the deflection of the cradle 50 is 15.4 mm. The stress of the cradle 50 is 182 megapascals (MPa). The deflection and stress experienced by the cradle 50 are well within the allowable range.

[0031] As described above, the cradle 50 is configured to support the point load of a single subject (patient) so that the subject can get on and off the cradle 50 using only the cradle 50. In particular, as shown in Figures 12 and 13, when the subject 22 (patient) gets on the cradle 50, the cradle 50 receives a load, and the subject applies the entire load to one or two small points with one or both hands, resulting in a concentrated load. The cradle 50 receives a load when the subject 22 (patient) applies a concentrated load to the cradle 50 via one or more hands, thereby applying the entire weight of the subject to one or two small points.

[0032] FIG. 14 shows an analysis of a load case (e.g., a patient load case) of the cradle 50 of FIG. 10. The boundary condition for the patient load case is that the cradle 50 is located outside the gantry. 150*150mm 2A concentrated load of 200 kg is applied to the cradle 50. Each side of the cradle 50 is supported by four rollers. Image 154 shows a first region 156 (the region near the end 70) where the concentrated load is applied to the side of the cradle 50. Image 158 shows the corresponding stress plot of the cradle 50 when the concentrated load is applied to the first region 156. The highest stresses applied to the cradle 50 were 74.4 MPa and 107 MPa. The deflection experienced by the cradle 50 is 2.6 mm.

[0033] Image 160 shows a second region 162 (near the center) where a concentrated load was applied to the side of cradle 50. Image 164 shows the corresponding stress plot of cradle 50 when a concentrated load was applied to second region 162. The highest stresses applied to cradle 50 were 110 MPa and 115 MPa. The deflection experienced by cradle 50 was 4.8 mm.

[0034] Image 166 shows a third region 168 (the region near end 68) where a concentrated load was applied to the side of cradle 50. Image 170 shows the corresponding stress plot for cradle 50 when a concentrated load was applied to third region 168. The highest stresses applied to cradle 50 were 96.4 MPa and 118 MPa. The deflection experienced by cradle 50 was 5.9 mm.

[0035] FIG. 15 illustrates attenuation at various points during imaging of a patient 22 using a typical cradle (e.g., during imaging using the CT imaging system 10). FIG. 15 shows an x-ray source 14 and an x-ray beam 16 emitted from the x-ray source. Shown in the path of the x-ray beam 16 are a filter 172 (e.g., a bowtie filter), the body of the patient 22, and a typical cradle 174. The patient 22 is positioned between the filter 172 and the cradle 174. The cradle 174 is positioned below the subject 22. The filter 172 is positioned between the x-ray source 14 and the body of the patient 22. Graph 176 represents the attenuation due to the filter 172. Graph 178 represents the attenuation due to the body of the patient 22. Graph 180 represents the attenuation due to the cradle 174. The typical cradle 174 is thicker (e.g., due to a foam core) than the cradles disclosed herein. As a result, typical cradles result in high attenuation and a high x-ray dose to patient 22 .

[0036] FIG. 16 illustrates the cradle 50 of the patient table shown in FIG. 2 relative to the path of x-rays passing through the patient 22 during a scan of the patient 22. As mentioned above, the cradle 50 is made of carbon fiber reinforced plastic. In certain embodiments, the cradle 50 does not include a foam core. The thin and slim construction of the cradle 50 (compared to a typical cradle, such as the cradle 174 of FIG. 15) ensures that the amount of composite material placed in the path taken by the x-rays 182 passing through the patient 22 is minimized, as shown in FIG. 16.

[0037] FIG. 17 illustrates attenuation at various points during imaging of a patient 22 (e.g., during imaging with the CT imaging system 10) utilizing the patient table cradle 50 shown in FIG. 2 . FIG. 17 illustrates the x-ray source 14 and the x-ray beam 16 emitted from the x-ray source. Shown in the path of the x-ray beam 16 are a filter 172 (e.g., a bowtie filter), the body of the patient 22, and the cradle 50. The patient 22 is positioned between the filter 172 and the cradle 50. The cradle 50 is positioned below the subject 22. The filter 172 is positioned between the x-ray source 14 and the body of the patient 22. Graph 184 illustrates the attenuation due to the filter 172. Graph 186 illustrates the attenuation due to the body of the patient 22. Graph 188 illustrates the attenuation due to the cradle 50. As discussed above, the cradle 50 is thinner and slimmer than a typical cradle (e.g., the cradle 174 of FIG. 15 ). Additionally, cradle 50 is wider than a typical cradle. Furthermore, in certain embodiments, cradle 50 does not include a foam core. As noted in FIG. 16 , the disclosed cradle 50 configuration ensures that a minimal amount of composite material is placed in the path of the x-rays passing through patient 22 (compared to a typical cradle, such as cradle 174 of FIG. 15 ). Attenuation by cradle 50 (as shown in graph 188) is significantly less than that by a typical cradle (as shown in graph 180 of FIG. 15 ). The reduced attenuation by cradle 50 allows for a lower x-ray dose to patient 22 (compared to utilizing a typical cradle).

[0038] FIG. 18 shows a table 190 of the results of an analysis of X-ray attenuation for both the typical cradle and the cradle 50 of the patient table shown in FIG. 2. Both a typical cradle with a foam core (e.g., referred to in table 190 as a foam core cradle) (e.g., cradle 177 of FIG. 15) and a cradle 50 without a foam core (e.g., referred to in table 190 as a slim cradle) are shown. A portion of the cradle 50 was three-dimensionally printed and used in comparative testing with the typical cradle. CT scans were performed on both the typical cradle and the cradle 50 using a CT imaging system while the X-ray source was placed under each cradle, varying the kilovolts (kV) and milliamperes (mA) parameters of the X-ray source. Dosimeters were placed in both the typical cradle and the cradle 50 to measure dose. As shown in Table 190, cradle 50 measured a higher dose compared to a typical cradle, and therefore, the patient's X-ray dose when using cradle 50 was lower than when using a typical cradle.

[0039] Additionally, image quality was verified using a typical cradle with a foam core versus a cradle 50 that does not include a foam core. FIG. 19 shows CT images of both the typical cradle and the cradle 50 of the patient table shown in FIG. 2. Both the typical cradle and cradle 50 were CT scanned using a CT imaging system with X-ray source parameters of 80 kV and 350 mA. Image 192 is a CT image of the typical cradle. Image 194 is an image of cradle 50. The image quality of cradle 50 is comparable to that of the typical cradle.

[0040] As described above, the wide-angle, non-trapping patient positioning and patient support can also be utilized in patient tables for other types of medical imaging systems (e.g., magnetic resonance imaging (MRI), positron emission tomography (PET) imaging systems, single photon emission computed tomography (SPECT) imaging systems, nuclear medicine imaging systems, x-ray imaging systems, etc.).

[0041] Technical effects of the disclosed subject matter include providing a patient table with a cradle that does not include side support structures to achieve a pinchless configuration in which no body part of the subject becomes pinched between the cradle and the fixed structure while the cradle is moving relative to the fixed structure. The cradle does not require side support structures; the cradle itself serves as a support structure for positioning the patient on the cradle. The disclosed table configuration eliminates the need for additional external supports or additional structures to hold and position the cradle. The elimination of side support structures and the increased width of the cradle prevent patients from developing kinesiphobia or claustrophobia. Technical effects of the disclosed subject matter further include providing a patient table that prevents patients from being surprised by feeling cold. Thus, the disclosed subject matter allows patients to feel comfortable. Technical effects of the disclosed subject matter also include providing a patient table that is easy to clean and disinfect, thereby reducing associated repair issues and therefore downtime of medical imaging systems. The technical effects of the disclosed subject matter further include providing a wide cradle with a flat surface that engages with the top of a radiation therapy table. The technical effects of the disclosed subject matter further include providing a thin, strong, and cost-effective part (i.e., the cradle) made from carbon fiber reinforced plastic. A simple layering process of carbon fiber reinforced plastic to manufacture the cradle improves production. The technical effects of the disclosed subject matter further include low x-ray attenuation by the cradle, resulting in a lower x-ray dose to the patient, which improves x-ray tube life and overall system throughput.

[0042] The technology presented and claimed herein refers to and applies to tangible objects and specific examples of a practical nature that demonstrably improve the art, and is therefore not abstract, intangible, or purely theoretical. Moreover, where a claim includes one or more elements designated as "means for [performing] ... [function]" or "steps for [performing] ... [function]," it is intended that such elements be construed under 35 U.S.C. 112(f). However, for claims including elements designated in other ways, it is intended that such elements not be construed under 35 U.S.C. 112(f).

[0043] This description uses examples to disclose the present subject matter, including the best mode, and also to enable any person skilled in the art to practice the subject matter, including making and using any devices or systems and performing any methods incorporating the same. The patentable scope of the present subject matter is defined in the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ in material way from the literal language of the claims. [Explanation of symbols]

[0044] 10 CT imaging systems 14 X-ray source 16 X-ray beams 40 patient tables 42 Fixed beam structure 44 Side support structure 46 Patient Tables 49 Longitudinal Axis 52 Base 58 Upper 62 Arrow 64 First Side 66 Second Side 68 First end 74 width 78 Fixed structure 80 First Aspect 82 Second Aspect 84 First end 86 Second end 88 width 90 portions 92 Central part 94 parts 96 parts 98 Vertical section 102 Bottom surface 102 bottom 106 depth 108 First Part 110 Second Part 112 dashed line 114 length 116 length 118 Table 154 images 156 First Area 158 images 160 images 162 Second Area 164 images 166 images 168 The Third Realm 170 images 172 filters 174 Cradle 176 graphs 177 Cradle 178 graphs 180 graphs 182 X-ray 184 graphs 186 graphs 188 graphs 190 table 192 images 194 images

Claims

1. 1. A patient table for a medical imaging system, comprising: base, a cradle configured to support a subject to be imaged and move in two directions relative to the base; and a stationary structure coupled to both the base and the cradle, the cradle configured to move relative to the stationary structure without a body part of the subject being trapped between the cradle and the stationary structure; The patient table, including

2. 2. The patient table of claim 1, wherein the cradle has a first width in a first direction perpendicular to a longitudinal axis of the cradle, the first width being greater than a second width in the first direction of the fixed structure.

3. The patient table of claim 2 , wherein the cradle is positioned above the fixed structure across the first width.

4. The patient table of claim 2 , wherein the first width is at least 42 centimeters.

5. The patient table of claim 2 , wherein a cross section of the cradle along the first width includes a plurality of portions, the plurality of portions having at least two portions that are inclined relative to a central portion of the plurality of portions.

6. The patient table of claim 2 , wherein the cradle varies in thickness about the longitudinal axis in both the first direction and a second direction perpendicular to the first direction.

7. 7. The patient table of claim 6, wherein the cradle includes a first portion and a second portion along the longitudinal axis, the first portion configured to extend beyond the stationary structure, the second portion configured to remain positioned above the stationary structure when the first portion extends beyond the stationary structure, the first portion having a first thickness in the second direction relative to the longitudinal axis, and the second portion having a second thickness in the second direction relative to the longitudinal axis, the second thickness being thicker than the first thickness.

8. 10. The patient table of claim 1, wherein the cradle is configured to support a point load of a single subject such that the subject can enter and exit the cradle using only the cradle.

9. The patient table of claim 1 , wherein the cradle is configured with a flat surface that engages a top of a radiation treatment table.

10. 10. The patient table of claim 1, wherein the cradle does not include a foam core, and wherein the cradle attenuates x-rays less than another cradle that does have a foam core.

11. The patient table of claim 10 , wherein the cradle comprises a foam core.

12. 1. A computed tomography (CT) imaging system, comprising: a gantry having a bore coupled to an imaging component configured to acquire imaging data of a subject; and 1. A patient table, comprising: base, a cradle configured to support a subject to be imaged and move in two directions relative to the base; and a stationary structure coupled to both the base and the cradle; Including, A CT imaging system, wherein the cradle has a first width in a first direction perpendicular to a longitudinal axis of the cradle, the first width being wider than a second width in the first direction of the fixed structure.

13. The CT imaging system of claim 12 , wherein the cradle is positioned above the stationary structure across the first width.

14. The CT imaging system of claim 12 , wherein the first width is at least 42 centimeters.

15. 13. The CT imaging system of claim 12, wherein a cross section of the cradle along the first width includes a plurality of portions, the plurality of portions having at least two portions that are inclined relative to a central portion of the plurality of portions.

16. 13. The CT imaging system of claim 12, wherein the cradle varies in thickness about the longitudinal axis in both the first direction and a second direction perpendicular to the first direction.

17. 17. The CT imaging system of claim 16, wherein the cradle includes a first portion and a second portion along the longitudinal axis, the first portion configured to extend into the bore, the second portion configured to remain positioned outside the bore and above the stationary structure when the first portion extends into the bore, the first portion having a first thickness in the second direction relative to the longitudinal axis, and the second portion having a second thickness in the second direction relative to the longitudinal axis, the second thickness being thicker than the first thickness.

18. 1. A patient table for an imaging system, comprising: base, a cradle configured to support a subject to be imaged and move in two directions relative to the base; and a stationary structure coupled to both the base and the cradle; Including, a patient table, the cradle including an upper surface and a lower surface, the cradle including a first portion and a second portion along a longitudinal axis of the cradle, the first portion configured to extend beyond the stationary structure, the second portion configured to remain positioned above the stationary structure when the first portion extends beyond the stationary structure, the first portion having a first thickness in a first direction between the upper and lower surfaces relative to the longitudinal axis, and the second portion having a second thickness in the first direction relative to the longitudinal axis, the second thickness being thicker than the first thickness.

19. 20. The patient table of claim 18, wherein the cradle is configured to support a point load of a single subject such that the subject can enter and exit the cradle using only the cradle.

20. 20. The patient table of claim 18, wherein the cradle has a width in a second direction perpendicular to a longitudinal axis of the cradle, and a cross section of the cradle along the width includes the plurality of portions, the plurality of portions having at least two portions that are inclined relative to a central portion of the plurality of portions.

Images