Patent Publication Number: US-2021186790-A1

Title: Table System for Medical Imaging

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The subject patent application is a Continuation of U.S. patent application Ser. No. 15/685,955, filed on Aug. 24, 2017, which claims priority to all the benefits of U.S. Provisional Patent Application No. 62/380,595, filed on Aug. 29, 2016, the disclosures of each of which are hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND 
     A variety of patient supports (e.g., tables) are used for different medical imaging applications, such as x-ray fluoroscopic and computed tomography (CT) imaging and magnetic resonance (MR) imaging. These patient supports are often designed for use with a particular device or type of imaging device. For example, a patient support for an x-ray CT imaging device may be designed and dimensioned for sliding a patient in and out of an imaging bore of the device. 
     In many cases, it can be difficult to load and unload patients from the supports commonly used with medical imaging equipment. In addition, conventional patient supports may be limited in the types imaging devices they can be used with and/or the positions in which they can support a patient. Conventional patient supports may also need to be made relatively large and/or heavy to minimize dynamic sagging as the support slides in and out of the bore of an imaging device. 
     There is a continuing need for an improved patient support for medical imaging. 
     SUMMARY 
     Embodiments include table systems for use with an imaging device that include a base portion that supports the table system over a support surface, a patient support including a platform sized and shaped to support a patient in a standing position and a bed sized and shaped to support the patient in a lying position, a linkage portion coupled between the base portion and the patient support that is pivotable with respect to both the base portion and the patient support, a first drive mechanism that drives the pivoting of the patient support with respect to the linkage portion, and a second drive mechanism that drives the pivoting of the linkage portion with respect to the base portion, the first and second drive mechanisms moving the patient support between a vertical position in which the platform is substantially parallel to the support surface and a horizontal position in which the bed is substantially parallel to the support surface. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the present invention will be apparent from the following detailed description of the invention, taken in conjunction with the accompanying drawings of which: 
         FIG. 1  is a perspective view of a table system with a patient support in a vertical position according to an embodiment. 
         FIG. 2  is a side view of a table system illustrating the pivoting motion of the patient support according to an embodiment. 
         FIG. 3  is a perspective view of a table system with a linkage portion pivoted upwards and the patient support pivoted to a horizontal position. 
         FIG. 4  is a perspective view of a table system with the patient support in a lowered position. 
         FIG. 5  is a front perspective view of a table system with the patient support pivoted upwards to a vertical position. 
         FIG. 6  is a rear perspective view of a table system with a covering of the linkage portion partially removed. 
     
    
    
     DETAILED DESCRIPTION 
     The various embodiments will be described in detail with reference to the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. References made to particular examples and implementations are for illustrative purposes, and are not intended to limit the scope of the invention or the claims. 
     Embodiments include a table system for use with an imaging device, such as a diagnostic medical imaging device. As shown in  FIGS. 1-6 , a table system  100  according to various embodiments may include a base portion  101  configured to support the table system  100  over a support surface (e.g., a floor  102 ), a patient support  103  which includes a platform  105  sized and shaped to support a patient in a standing position and a bed  107  sized and shaped to support the patient in a lying position, and a linkage portion  109  coupled between the base portion  101  and the patient support  103  that is pivotable with respect to both the base portion  101  and the patient support  103 . A first drive mechanism may be located in the linkage portion  109  and may drive the pivoting of the linkage portion  109  with respect to the patient support  103 . A second drive mechanism may also be located in the linkage portion  109  and may drive the pivoting of the linkage portion  109  with respect to the base portion  101 . In embodiments, the patient support  103  may be positioned in a vertical position (as shown in  FIGS. 1, 5 and 6 ) in which the platform  105  is substantially parallel to the support surface (e.g., floor  102 ) and a horizontal position (as shown in  FIGS. 3 and 4 ) in which the bed  107  is substantially parallel to the support surface (e.g., floor  102 ). As used herein, the term “substantially parallel” means±15° from an exactly parallel position. The patient support  103  may be positioned at any arbitrary angle between a horizontal and vertical configuration. As shown in  FIG. 2 , for example, the patient support  103  may be tilted at a 45° angle between a vertical and horizontal position. In embodiments, the patient support  103  may stably support the full weight of a human body and may support greater than 200 kg, such as up to about 800 kg, over the full range of pivoting motions of the patient support  103  and linkage portion  109 . 
     The patient support  103  may include an elongated first portion  111  having a surface forming the bed  107  which may support a patient in a lying or inclined position and a second portion  113  having a surface forming the platform  105  which may support a patient in a weight-bearing standing or inclined position. The first portion  111  may have a length dimension that is preferably greater than the average height of an adult human, such as between 2-3 meters (e.g., about 2.5 meters). The second portion  113  may extend substantially perpendicular to the first portion  111  at a first end  115  of the first portion  111 . As used herein, the term “substantially perpendicular” means±15° from an exactly perpendicular position. The second portion  113  may have a length dimension that is less than the length dimension of the first portion  111 . In embodiments, the length dimension of the second portion  113  may be between 20-50 cm (e.g., about 35 cm), and may be greater than the average foot length of an adult human to enable a patient to comfortably stand on the platform  105 . The width of the first and second portions  111 ,  113  may be greater than the average width of an adult human (e.g., average shoulder width in the case of the first portion  111  and/or average stance width in the case of the second portion  113 ) and may be at least about 40 cm. The width of the first and/or second portions  111 ,  113  may be less than a bore diameter of a medical imaging device (e.g., an x-ray CT scanner or MRI device), such as less than about 120 cm, and may be between about 50 and 80 cm. 
     The bed  107  of the first portion  111  may be concavely curved, as is most clearly visible in  FIG. 5 . The distal end  117  of the first portion  111  may have a curved edge, as shown for example, in  FIG. 1 . The platform  105  of the second portion  113  may also have a similar curved edge. The rounded and/or curved surfaces of the patient support  103  may help to minimize beam attenuation by the patient support  103  during an imaging scan. 
     As shown in  FIGS. 1-6 , the patient support  103  may include a pair of bracket members  119  that may extend away from a rear surface  121  of the second portion  113  of the patient support  103  (i.e., opposite the platform  105 , as shown in  FIGS. 2-4 ). The bracket members  119  may be connected to the linkage portion  109  along an axis a to enable the patient support  103  to pivot with respect to the linkage portion  109 , as described in further detail below. 
     The patient support  103  may be made of one or more suitable high-strength materials. In preferred embodiments, the patient support  103  may be made of a radiolucent (i.e., x-ray transparent) material, such as carbon fiber. In one embodiment, the patient support  103  may comprise a single piece of carbon fiber that may form at least the bed  107  and the platform  105 . The carbon fiber element may form a rigid outer shell that may contain a suitable lightweight and radiolucent filler material, such as a foam. The patient support  103  may include additional structural reinforcing elements (e.g., plates, rods, brackets, etc.) that may or may not be radiolucent. For example, the patient support  103  may include one or more metal (e.g., aluminum, steel, etc.) support plates which may be secured to a carbon fiber patient support structure using fasteners. In embodiments in which the patient support  103  includes structural reinforcing elements made from a non-radiolucent material, such as aluminum, the non-radiolucent material may preferably be located so as not to interfere with an imaging scan of a patient on the patient support  103 . For example, in the embodiment of  FIGS. 1-6 , an aluminum support frame may be confined to the brackets  119 , at or near to the rear surface  121  of the second portion  113  and/or adjacent to the first end  115  of the first portion  111 . This may enable a patient standing on the platform  105  to be scanned over the entire length of the body including through the feet without interference (i.e., image artifacts) from non-radiolucent reinforcing element(s). 
     The base portion  101  of the table system  100  may include a pair of parallel bracket members  201 . The bracket members  201  may be fixed to the floor or other stable support surface using fasteners, such as bolts. The bracket members  201  of the base portion  101  may be made of a suitable high-strength structural material, such as aluminum or steel. The bracket members  201  may have an angled upper surface  203  as shown in  FIGS. 2-6 . The angled upper surface  203  of the bracket members  201  may be complementary to an angled surface  123  of the bracket members  119  of the patient support  103 , as shown in  FIG. 1 . The bracket members  201  of the base portion  101  may be connected to the linkage portion  109  along an axis a′ to enable the linkage portion  109  to pivot with respect to the base portion  101  as described in further detail below. 
     The linkage portion  109  may include a flat first major surface  301  and a flat second major surface  303  that extends parallel to the first surface  301 . The bracket members  201  of the base portion  101  and the bracket members  119  of the patient support  103  may connect to the linkage portion  109  via opposing first and second side walls  305 ,  307  of the linkage portion  109 . 
     A first rotary drive shaft  309  (see  FIG. 6 ) may extend through one or both side walls  305 ,  307  of the linkage portion  109  and connect to at least one bracket member  119  of the patient support  103 . At least one rotary bearing within the linkage portion  109  may enable the first rotary drive shaft to rotate with respect to the linkage portion  109  to pivot the patient support  103  with respect to the linkage portion  109  about axis a. 
     A second rotary drive shaft  311  (see  FIG. 6 ) may extend through one or both side walls  305 ,  307  of the linkage portion  109  and connect to at least one bracket member  201  of the base portion  101 . At least one rotary bearing within the linkage portion  109  may enable the linkage portion  109  to rotate with respect to the second rotary drive shaft  311  to cause the linkage portion  109  to pivot with respect to the base portion  101  about axis a′. 
     The linkage portion  109  may be made from durable, high-strength material(s) to provide a high degree of structural integrity and to prevent the components within the linkage portion  109  from being damaged. In one embodiment, as shown in  FIG. 6 , the linkage portion  109  may include a rigid support frame  313  made from a suitable high-strength metal material, such as aluminum or steel. The support frame  313  may include a support plate  315  extending adjacent and parallel to the first major surface  301  of the linkage portion  109 . A similar support plate may extend adjacent and parallel to the second major surface  303  of the linkage portion  109 . First and second drive systems  317 ,  319  for driving the rotation of the linkage portion  109  with respect to the patient support  103  and base portion  101  may be located at least partially between the two support plates  315 . As shown in  FIG. 6 , one or more block members  321  for supporting rotary bearing(s)  323  for a rotary drive shaft  311  may be secured between the support plates  315 . A similar configuration may also be located on the opposite side of the linkage portion  109  to support the other rotary drive shaft  309 . 
     The linkage portion  109  may include an outer shell  325  enclosing an interior housing  327  that may contain the support frame  313 , rotary bearings  313 , rotary drive shafts  309 ,  311  and drive systems  317 ,  319 .  FIG. 6  illustrates the linkage portion  109  with the outer shell  325  partially removed. The outer shell  325  may define the first and second major surfaces  301 ,  303  and sidewalls  305 ,  307 ,  308  and  310  of the linkage portion  109 . As shown, for example, in  FIG. 2 , the third and fourth sidewalls  308  and  310  of the linkage portion  109  may have a rounded contour to enable the linkage portion  109  to pivot with respect to the ground and the patient support  103  with minimal clearance. In embodiments, the outer shell  325  may be made from a plastic or carbon fiber material. 
       FIG. 6  illustrates the drive systems  317 ,  319  for driving the rotation of the rotary drive shafts  309 ,  311  relative to the linkage portion  109 . In embodiments, the drive systems  317 ,  319  may have a mirrored configuration where two drive systems are rotated 180° within the interior housing  327  of the linkage portion  109 . For example, a first drive system  317  for driving the rotation of the first rotary drive shaft  309  may include a first motor  329  between the support plates  315  that may be geared in to a first drive chain  331  that meshes with a first sprocket wheel  333  coupled to the first rotary drive shaft  309 . Thus, the first motor  329  may drive the rotation of the first rotary drive shaft  309  and the pivoting of the patient support  103  with respect to the linkage portion  109 . A second drive system  319  coupled to the second rotary drive shaft  311  may include a second motor between the support plates  315  (not visible in  FIG. 6 ) that may be geared in to a second drive chain  335  that meshes with a second sprocket wheel  337  coupled to the second rotary drive shaft  311 . The second sprocket wheel  337  and the second rotary drive shaft  311  may be fixed to the base portion  101  of the table system  100  (e.g., between bracket members  201 ). The second motor may drive the second drive chain  335  around the second sprocket wheel  337 , causing the linkage portion  109  to rotate on the rotary bearing(s) and pivot with respect to the base portion  101 . Rotary encoders may be provided on one or more of the motor, gears or rotary bearings of each of the drive systems  317 ,  319  for indicating the relative rotational positions of the base portion  101 , linkage portion  109  and patient support  103 . 
     As shown in  FIG. 1 , in some embodiments, the entire table system  100  may be rotated and/or translated along at least one direction. For example, the base portion  101  of the system  100  may be mounted to a platform  400  on a rotating bearing to enable the table system  100  to be rotated in the direction of arrow  401 . The rotating platform  400  may be mounted to a rail system  402  to enable the table system  100  to translate in at least one direction, such as along the direction of arrows  403  and/or arrows  405 . The rotation and translation motion of the table system  100  may enable a patient to be loaded onto the patient support  103  when the table system  100  in a first position and orientation and then moved to a second position and/or orientation to perform an imaging scan. For example, the table system  100  may be rotated such that the patient support  103  is oriented in line with a patient imaging axis of an imaging device (such as an x-ray CT scanner). Where the imaging device has a fixed bore, the entire table system  100  with the patient supported thereon may be translated into the bore. It is noted that the relative rotational positions of the base portion  101 , linkage portion  109  and patient support  103  may remain fixed during the scan such that the torque forces experienced along the length of the patient support  103  remains constant, even when the table system  100  translates into the imaging bore. Thus, there may be no dynamic sagging of the patient support  103  during an imaging scan. 
     It will be understood that in some embodiments, the table system  100  may be fixed to a floor or other support surface  102  and may not rotate and/or translate as illustrated in  FIG. 1 . 
     A control system  500  (e.g., a processor and memory) may be operatively coupled to the table system  100 , as schematically illustrated in  FIG. 6 . The control system  500  may be located partially or completely within the table system  100  (e.g., within the linkage portion  109 ) and/or within one or more separate components, such as a workstation, an imaging system or a mobile cart. The control system  500  may receive position feedback data (e.g., rotary encoder data) from the table system  100  and may send control signals to the motor(s) of the table system  100  to cause the motors to drive one or both of the rotary drive shafts  309 ,  311  and pivot the linkage portion  109  and/or the patient support  103  into a desired configuration. The linkage portion  109  and/or the patient support  103  may be pivoted to one or more pre-set configurations of the table system  100  (e.g., stored in the memory of the control system  500 ) and/or the configuration may be controllably adjusted by a user using a suitable user input device  501  (e.g., buttons, joystick, computer keyboard and/or mouse, touchscreen display, etc.). 
     Various pivot motions and operating modes of a table system  100  according to an embodiment are now described with reference to  FIGS. 1-5 . In embodiments, the table system  100  may be used to support a patient while performing a variety of imaging scans of the patient using an imaging system. The imaging system may be an x-ray computed tomography (CT) imaging system. Examples of x-ray CT imaging devices that may be used according to various embodiments are described in, for example, U.S. Pat. No. 8,118,488, U.S. Patent Application Publication No. 2014/0139215, U.S. Patent Application Publication No. 2014/0003572, U.S. Patent Application Publication No. 2014/0265182, U.S. Patent Application Publication No. 2014/0275953, U.S. Provisional Patent Application No. 62/425,746 and U.S. application Ser. No. 15/130,258, the entire contents of all of which are incorporated herein by reference. It will be understood that these embodiments are provided as illustrative, non-limiting examples of imaging systems suitable for use with a table system  100  according to various embodiments, and that an embodiment table system  100  may utilize various types of medical imaging devices. For example, alternatively or in addition to an x-ray CT device, a table system  100  of the various embodiments may be used with an x-ray fluoroscopic imaging device, a magnetic resonance (MR) imaging device, a positron emission tomography (PET) imaging device, a single-photon emission computed tomography (SPECT), an ultrasound imaging device, etc. 
     In one non-limiting embodiment, the table system  100  may be used to obtain diagnostic images of a patient in a standing or weight-bearing position. A patient may stand on the platform  105  of the patient support  103 , optionally with their body leaning or resting against the bed  107 . A gantry of an imaging system may be moved such that the patient and patient support  103  are positioned within the bore of the gantry, such as by lowering the gantry over the patient and patient support  103  (or alternatively, raising the patient and patient support  103  into the bore of the gantry). An example of a system for performing an x-ray CT imaging scan of a patient in a weight-bearing position is described in U.S. Patent Application Publication No. 2014/0139215, which was previously incorporated by reference. 
     In some embodiments, the table system  100  may be used to move a patient between a lying position (i.e., where the patient support  103  extends in a generally horizontal direction with the patient supported primarily by bed  107 ) and a standing or weight-bearing position (i.e., where the patient support  103  extends in a generally vertical direction with the patient supported primarily by platform  105 ). In embodiments, a patient may be first loaded onto the patient support  103  in a lying position. The feet of the patient may be adjacent to the platform  105 . An optional restraint (e.g., one or more Velcro® straps) may be utilized to secure the patient to the patient support  103 . The patient support  103  along with the patient may then be tilted up into a standing or weight-bearing position. Alternately, the patient may be loaded onto the patient support  103  in a standing position (e.g., the patient may step up onto the platform  105 ) and the patient support  103  along with the patient may be tilted down into a lying position. 
       FIG. 1  illustrates the table system  100  in a first configuration. In this configuration, the linkage portion  109  lies flat and parallel to the support surface  102  (e.g., the floor). The bracket members  201  of the base portion  101  and the bracket members  119  of the patient support  103  are adjacent to the first and second side walls  305 ,  307  (see  FIGS. 2-3 ) of the linkage portion  109 . The second portion  113  of the patient support  103  may extend over and parallel to the first major surface  301  of the linkage portion  109 . The first portion  111  of the patient support  103  may extend vertically upward from and perpendicular to the first major surface  301  of the linkage portion  109 . The configuration of  FIG. 1  may provide a relatively small footprint with the base portion  101 , linkage portion  109  and patient support  103  folded over one another in a compact manner. 
       FIG. 2  illustrates the pivoting motion of the patient support  103  with respect to the linkage portion  109  in the direction of arrow  600 . In  FIG. 2 , the patient support  103  is tilted about 45° with respect to the linkage portion  109 . In embodiments, the patient support  103  may pivot with respect to the linkage portion  109  over a range of at least about 90°, and preferably at least 180° such as up to about 270°. 
       FIG. 3  illustrates the pivoting motion of the linkage portion  109  with respect to the base portion  101  in the direction of arrow  601 . As shown in  FIG. 3 , the linkage portion  109  is pivoted about axis a′ by 90° such that the first and second major surfaces  301 ,  303  of the linkage portion  109  extend in a vertical direction and are oriented perpendicular to the support surface  102  (e.g., floor). In the configuration of  FIG. 3 , the patient support  103  is pivoted 180° relative to the configuration of  FIG. 1 , such that the second portion  113  of the patient support  103  is now offset from and parallel to the second major surface  303  of the linkage portion  109 . The first portion  111  of the patient support  103  extends in a horizontal direction perpendicular to the second major surface  303  of the linkage portion  109 . 
       FIG. 4  shows another configuration in which the linkage portion  109  has been pivoted 180° from the configuration of  FIG. 1  such that the first major surface  301  of the linkage portion  109  now lies horizontal against the support surface  102  (e.g., the floor) and the second major surface  303  of the linkage portion  109  faces vertically upwards. In this configuration, the patient support  103  has been pivoted 270° relative to the configuration of  FIG. 1 , such that the second portion  113  of the patient support  103  extends vertically upward from and perpendicular to the second major surface  303  of the linkage portion  109 , and the first portion  111  of the patient support  103  extends in a horizontal direction over and parallel to the second major surface  303  of the linkage portion  109 . 
     An advantage of the configuration of  FIG. 4  is that it may facilitate easy loading and unloading of a patient to and from the patient support  103 . In many cases, it can be challenging for a patient to get onto or be placed onto a conventional table for an imaging device. Often, particularly in the case of sick or infirm patients, this may require lifting patient from a gurney up onto a dedicated radiology table, which can be problematic for the medical staff. A table system  100  according to various embodiments may be lowered such as shown in  FIG. 4  so that the bed  107  on which the patient is supported may be at a comfortable height for loading and unloading of the patient. For example, the bed  107  may be at a height of no more than about 50 cm, such as between 30 and 40 cm from the floor. This may allow a patient to easily climb onto or be lowered down onto the bed  107 , which may be easier for both the patient and the medical staff members. 
     The patient support  103  may then be raised from the lowered position of  FIG. 4  to a height suitable for an imaging scan (e.g., such that the patient support  103  may be positioned within the bore of an imaging device). In embodiments, the patient support  103  may be raised to raise the bed  107  to a height of one meter or more from the floor.  FIG. 3  shows the patient support  103  raised to a maximum height for performing a scan of a patient supported in a horizontal lying position on the bed  107 . The patient support  103  may be raised to any height between the lowered position in  FIG. 4  and the raised position of  FIG. 3  by controlling the relative pivoting motions of the base portion  101 , linkage portion  109  and patient support  103 . A control system  500  of the table system  100  (see  FIG. 6 ) may coordinate the pivoting motions so that bed  107  stays generally horizontal as the patient support  103  is raised and lowered. The bed  107  may also be moved to an inclined position at any arbitrary angle (e.g., ±30° from the horizontal position shown in  FIGS. 3 and 4 ). In embodiments, this may enable the patient to be supported in Trendelenburg and/or reverse Trendelenburg positions. 
       FIG. 5  illustrates the table system  100  in a configuration suitable for imaging a patient in a standing or weight-bearing position. In embodiments, the patient support  103  may be pivoted upwards by a pre-determined angle (e.g., 90°) from the lowered position shown in  FIG. 4  to the position shown in  FIG. 5 . In the configuration of  FIG. 5 , the patient support  103  is supported in a cantilevered manner from the linkage portion  109  by the bracket members  119 . The patient may be supported in a standing position on the platform  105 , which is parallel to the support surface  102  (e.g., floor). The patient support  103  may be pivoted to any arbitrary angle with respect to the linkage portion  109 , such as an angle between 0-90° from the surface  303  of the linkage portion  109  so that the weight of the patient may be partially supported by the platform  105  and partially supported by the bed  107 . An imaging gantry of an imaging device (e.g., x-ray CT scanner) may scan the entire length of the patient without interference from either the linkage portion  109  or the base portion  101  of the table system  100 . 
     Various examples of diagnostic imaging applications that may be performed on a human or animal patient in a weight-bearing position using the present table system  100  include, without limitation: 
     Imaging the bones of a foot. The three-dimensional relationships of the bones in the foot in a flatfoot deformity are difficult to assess with standard radiographs. CT scans demonstrate these relationships but are typically made in a non-weightbearing mode. The use of a weightbearing CT or other imaging apparatus may be useful in imaging the feet in patients with severe flexible pesplanus deformities and to better define the anatomical changes that occur. 
     Imaging of a limb (e.g. leg). Weight-bearing (CT) bilateral long leg hip to ankle examination and non-weight bearing cross-sectional imaging (CT) of the affected limb may be performed on the hip, knee and ankle, for example, and may be useful for determining variations in angulation and alignment accuracy for diagnosis and/or surgical planning. 
     Imaging of a spine. Weight bearing scanning (e.g., CT scanning) may be useful for improvements in the accurate diagnosis of degenerative spinal disorders by scanning a patient in the “real life” standing position. By scanning in the standing position, the spinal disc and facet joint compresses, which may enable more specific and precise diagnosis of degenerative spine disorders. 
     Imaging of a joint (e.g., knee). Weight bearing scanning (e.g., CT scanning) of the knee may enable more specific and precise diagnosis of the patella-femoral kinematics and may also be useful in surgical planning. 
     Angiography. Weight bearing angiography (e.g., CT angiography) may enable more accurate diagnosis, and may be used, for example, to examine the pulmonary arteries in the lungs to rule out pulmonary embolism, a serious but treatable condition. Weight bearing angiography may also be used to visualize blood flow in the renal arteries (those supplying the kidneys) in patients with high blood pressure and those suspected of having kidney disorders. Narrowing (stenosis) of a renal artery is a cause of high blood pressure (hypertension) in some patients and can be corrected. A special computerized method of viewing the images makes renal CT angiography a very accurate examination. This is also done in prospective kidney donors. Weight bearing angiography may also be used to identify aneurysms in the aorta or in other major blood vessels. Aneurysms are diseased areas of a weakened blood vessel wall that bulges out—like a bulge in a tire. Aneurysms are life-threatening because they can rupture. Weight bearing angiography may also be used to identify dissection in the aorta or its major branches. Dissection means that the layers of the artery wall peel away from each other—like the layers of an onion. Dissection can cause pain and can be life-threatening. Weight bearing angiography may also be used to identify a small aneurysm or arteriovenous malformation inside the brain that can be life-threatening. Weight bearing angiography may also be used to detect atherosclerotic disease that has narrowed the arteries to the legs. 
     A table system  100  such as shown and described may also be used to support a patient for interventional radiology procedures and external beam radiation (e.g., LINAC) treatment procedures. 
     The foregoing method descriptions are provided merely as illustrative examples and are not intended to require or imply that the steps of the various embodiments must be performed in the order presented. As will be appreciated by one of skill in the art the order of steps in the foregoing embodiments may be performed in any order. Words such as “thereafter,” “then,” “next,” etc. are not necessarily intended to limit the order of the steps; these words may be used to guide the reader through the description of the methods. Further, any reference to claim elements in the singular, for example, using the articles “a,” “an” or “the” is not to be construed as limiting the element to the singular. 
     The preceding description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the invention. Thus, the present invention is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.