System and method to provide feedback regarding image navigation

Abstract

A method and system are disclosed for acquiring image data of a subject. The image data can be collected with an imaging system in a selected manner and / or motion. More than one projection may be combined to generate and create a selected view or visualization of the subject. The visualization may be registered to a subject.

Description

SYSTEM AND METHOD TO PROVIDE FEEDBACKREGARDING IMAGE NAVIGATIONFIELD

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 653,653, filed 30 May 2024, the entire content of which is incorporated herein by reference.

[0002] The present disclosure relates to imaging a subject and registering a space to an image or subject, and particularly to a feedback regarding the same.BACKGROUND

[0003] This section provides background information related to the present disclosure which is not necessarily prior art.

[0004] A subject, such as a human patient, may undergo a procedure. The procedure may include a surgical procedure to correct or augment an anatomy of the subject. The augmentation of the anatomy can include various procedures, such as movement or augmentation of bone, insertion of an implant (i.e. an implantable device), or other appropriate procedures.

[0005] A surgeon can perform the procedure on the subject with images of the subject that are based on projections of the subject. The images may be generated with imaging systems such as a magnetic resonance imaging (MRI) system, computed tomography (CT) system, fluoroscopy (e.g. C-Arm imaging systems), or other appropriate imaging systems.

[0006] An image space may be registered to a subject space. In various embodiments, registration may be provided by identifying points in both the image space and the subject space. The registration may allow for navigation.SUMMARY

[0007] This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

[0008] According to various embodiments, a system to acquire image data of a subject may include an imaging system that may use various imaging modalities, such as x-rays, magnetic resonance, emissions (e.g., photon emissions), etc. to acquire image data. The subject may be a living patient (e.g., a human patient). The subject may also be a non-living subject, such as an enclosure, a casing, etc. The imaging system may include a moveable source and / or detector that is moveable relative to the subject.

[0009] The imaging system may include a movable source and / or detector to create a plurality of projections of the subject. The imaging system may also or alternatively acquire image data of a volume. Thus, the image data may be acquired as two-dimensional (2D) image data, three-dimensional (3D) image data, or other appropriate types of image data. Further, two or more portions may be used to generate an image that may also be referred to as a model based on the image data. This may include stitching together two or more 2D images or generating a 3D model.

[0010] Image data that is acquired of the subject generally needs to be registered to the subject to allow for navigation of a tracked instrument. Thetracked instrument may be any appropriate member, such as an implant, a surgical instrument, a probe, or other member that is tracked with a tracking or navigation system. The registration may include a transformation map between the space or volume defined by and relative to the subject in the physical world and the image volume or space defined by the image. Each of these spaces may have a coordinate system that can be registered to one another.

[0011] In various embodiments, a touchless registration system may be provided. In a touchless registration system, a scanner may be used to scan a volume (e.g., 3D scan) of the subject to identify one or more points thereon. A plurality of points may be defined relative to the subject. The points may be on a surface (e.g., skin) of the subject. The points or a mesh defined relative thereto may then be registered to points defined in the image. The registration may match points in the subject and in the image to allow for transformation between the two coordinate systems.

[0012] In various embodiments, the touchless registration system may allow for scanning the subject with an image scanner, such as a handheld image scanner. The image scanner may scan with visible light or infrared light that is reflected from the subject and captured by an image capturing device, such as a photo receptor member including a Complementary metal-oxide-semiconductor (CMOS). The scanner may be a three-dimensional scanner. The scanner may be tracked by the navigation system such that a pose of the scanner may be determined during the scanning of the subject. Thus, the navigation system mayregister the subject space to the image space based upon the three-dimensional scan of the subject with the touchless scanner.

[0013] Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0015] Fig. 1 is an environmental view of an imaging system in an operating theater;

[0016] Fig. 2 is a schematic environmental view of a registration assembly and a subject, according to various embodiments;

[0017] Fig. 3 is a schematic view of a registration data set, according to various embodiments;

[0018] Fig. 4 is a schematic environmental view of a subject tracker and a subject, according to various embodiments;

[0019] Fig. 5 is a display of a registered image and an estimated registration error, according to various embodiments;

[0020] Fig. 6 is a display of a registered image and an estimated registration error, according to various embodiments; and

[0021] Fig. 7 is a flowchart of a process to determine and output an estimated registration error including automatically, according to various embodiments.

[0022] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.DETAILED DESCRIPTION

[0023] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0024] The subject disclosure is directed to an exemplary embodiment of a surgical procedure on a subject, such as a human patient. It is understood, however, that the system and methods described herein are merely exemplary and not intended to limit the scope of the claims included herein. In various embodiments, it is understood, that the systems and methods may be incorporated into and / or used on non-animate objects. The systems may be used to, for example, image and register coordinate systems between two systems for use on manufacturing systems, maintenance systems, and the like. For example, automotive assembly may use one or more robotic systems including individual coordinate systems that may be registered together for coordinated or consorted actions. Accordingly, the exemplary illustration of a surgical procedure herein is not intended to limit the scope of the appended claims.

[0025] Various members or portions thereof may also be tracked relative to the subject. For example, a tracking system may be incorporated into a navigation system to allow tracking and navigation of one or more instruments(which may be the members) that may be tracked relative to the subject. The subject may also be tracked. The navigation system may include one or more tracking systems that track various portions, such as tracking devices, associated with instruments. The tracking system may include a localizer that is configured to determine the pose of the tracking device in a navigation system coordinate system. The pose may include any number of degrees of freedom, such as a three- dimensional location (e.g., x, y, z) and an orientation (e.g., yaw, pitch, and roll). Techniques, systems, or processes to determine the navigation system coordinate system may include those described at various references including U.S. Pat. No. 8,737,708; U.S. Pat. No. 9,737,235; U.S. Pat. No. 8,503,745; U.S. Pat. No. 8,175,681 ; and U.S. Pat. No. 11 ,135,025; all incorporated herein by reference. In particular, a localizer may be able to track an object within a volume relative to the subject. The navigation volume, in which a device may be tracked, may include or be referred to as the navigation coordinate system or navigation space. A determination or correlation between two coordinate systems may allow for or also be referred to as a registration between two coordinate systems. The registration may be performed according to various techniques and with various systems, including those disclosed herein.

[0026] Image data may be acquired for use and / or to generate images, which may also be referred to as image visualizations, of selected portions of a subject. The images may be displayed for viewing by a user, such as a surgeon. In various embodiments, superimposed on at least a portion of the image may be a graphical representation of a tracked portion or member, such as aninstrument. The graphical representation may be generated (e.g., by a processor module executing instructions) entirely as a graphic that represents the instrument. According to various embodiments, the graphical representation at the tracked pose relative to the subject may be superimposed on the image at an appropriate pose related to the tracked pose due to registration of an image space (also referred to as an image coordinate system) to a subject space. A method to register a subject space defined by a subject to an image space may include those disclosed in U.S. Pat. Nos. U.S. Pat. No. 8,737,708; U.S. Pat. No. 9,737,235; U.S. Pat. No. 8,503,745; and U.S. Pat. No. 8,175,681 ; all incorporated herein by reference.

[0027] During a selected procedure, one or more coordinate systems may be registered to the subject space or subject coordinate system due to a selected procedure, such as imaging of the subject. In various embodiments, at least one coordinate system may be registered to the subject by imaging the subject with a fiducial portion that is fixed relative to the first member or system, such as a robotic system or other instrument. The known position of the fiducial relative to any portion, such as the robotic system or the subject, may be used to register the subject space relative to any coordinate system in which the fiducial may be determined (e.g., by imaging or detecting (e.g., touching)). A registration of another coordinate system may allow for tracking of additional elements not fixed to a first portion, such as a robot that has a known coordinate system. In various embodiments, a patient tracker may be connected with a patient and imaging the patient tracker with a touchless registration system may also occur.

[0028] The tracking of an instrument during a procedure, such as a surgical or operative procedure, allows for navigation of a procedure. The navigation may be used to determine a pose of one or more portions, such as an instrument. The pose may include any number of degrees of freedom, such as a three-dimensional location (e.g., x, y, z) and three degrees of freedom of orientation (e.g., yaw, pitch, and roll). When image data is used to define an image space it can be correlated or registered to a physical space defined by a subject, such as a patient. According to various embodiments, therefore, the patient defines a patient space in which an instrument can be tracked and navigated. The image space defined by the image data can be registered to the patient space defined by the patient. The registration can occur with the use of fiducial points that can be identified in the image data and in the patient space. The fiducial points may be artificial points (e.g., members placed relative to the subject) or naturally occurring points (e.g., skin contours, boney portions).

[0029] Fig. 1 is a diagrammatic view illustrating an overview of a procedure room or arena. In various embodiments, the procedure room may include a surgical suite in which may be placed a robotic system 20 and a navigation system 26 that can be used for various procedures. The robotic system 20 may include a MazorX™ robotic guidance system, sold by Mazor Robotics Ltd. having a place of business in Israel and / or Medtronic, Inc. having a place of business in Minnesota, USA and / or as disclosed in U.S. Pat. No. 11 ,135,025, incorporated herein by reference. The robotic system 20 may be used to assist inguiding a selected instrument, such as drills, screws, be an ultrasound (US) probe33, etc. relative to a subject 30.

[0030] The robotic system 20 may include a mount 34 that fixes a portion, such as a robotic base 38, relative to the subject 30. The robotic system 20 may include one or more arms 40 that are moveable or pivotable relative to the subject 30, such as including an end effector 44. The end effector 44 may be any appropriate portion, such as a tube, guide, or passage member. Affixed to and / or in place of the end effector may be the imaging system that may be the US probe 33. A robotic processor module 53 may be used to control (e.g., execute instructions) to move and determine a pose of the end effector, such as relative to the base 34. The pose of the base 34 may be known in a coordinate system, such as the patient space of the patient 30 and / or the image coordinate system due to a registration as discussed above and exemplary disclosed in U.S. Pat. No. 11 ,135,025, incorporated herein by reference.

[0031] The navigation system 26 can be used to navigate the various portions due to the tracked the pose of one or more tracking devices, tracking devices may include a robot tracking device 54, a subject tracking device 58, an imaging system tracking device 62, a tool tracking device 66, and / or an US probe tracking device 81 . Each of the tracking devices may be used to track one or more portions, including those illustrated as being attached to the respective tracking devices.

[0032] An imaging device or system 80 may be an additional or alternative imaging system that may be used to acquire pre-, intra-, or post-operative or real-time image data of a subject, such as the subject 30, and may be tracked with the image system tracking device 62. It will be understood, however, that any appropriate subject can be imaged and any appropriate procedure may be performed relative to the subject. In the example shown, the imaging device 80 comprises an O-arm® imaging device sold by Medtronic Navigation, Inc. having a place of business in Louisville, Colorado, USA. The imaging device 80 may have a generally annular gantry housing 82 in which an image capturing portion is moveably placed. The imaging device 80 can include those disclosed in U.S. Pat. Nos. 7,188,998; 7,108,421 ; 7,106,825; 7,001 ,045; and 6,940,941 ; all of which are incorporated herein by reference, or any appropriate portions thereof.

[0033] The imaging system 80 may move, as a whole or in part, relative to the subject 30. For example, a source and a detector can move in a 360° motion around the patient 30, such as within the gantry 82. Also, the gantry 82 can move isometrically (also referred as “wag”) relative to the subject 30 generally in the direction of arrow 200 around an axis, such as through a cart 160. The gantry 82 can also tilt relative to a long axis 206 of the patient 30. In tilting, a plane of the gantry 82 may tilt or form a non-orthogonal angle with the axis 206 of the subject 30. The gantry 82 may also move longitudinally in the direction of arrows 214 along the axis 206 relative to the subject 30 and / or the cart 160. Also, the cart 160 may move to move the gantry 82. Further, the gantry 82 can move up and down generally in the direction of arrows 218 relative to the cart 160 and / or the subject 30, generally transverse to the axis 206 and parallel with the axis 202.

[0034] It is further appreciated that the imaging device 80 may include in addition or alternatively a fluoroscopic C-arm. Other exemplary imaging devices may include fluoroscopes such as bi-plane fluoroscopic systems, ceiling mounted fluoroscopic systems, cath-lab fluoroscopic systems, fixed C-arm fluoroscopic systems, isocentric C-arm fluoroscopic systems, 3D fluoroscopic systems, etc. Other appropriate imaging devices can also include MRI, CT, ultrasound, etc. The various imaging systems may include or use one or more imaging modalities, such as x-ray, magnetic resonance, ultrasound, Positron emission tomography (PET) scans, combinations thereof, etc.

[0035] The position of the imaging system 33, 80, and / or portions therein such as the image capturing portion, can be precisely known relative to any other portion of the imaging device 33, 80. Also, the respective tracking devices may be used to track one or more portions of the respective imaging systems. The precise positioning and / or tracking can allow the imaging system 33, 80 and / or the navigation system 26 to know its position relative to the patient 30 or other references. In addition, as discussed herein, the precise knowledge of the position of the image capturing portion can be used in conjunction with a tracking system to determine the position of the image capturing portion and the image data relative to the tracked subject, such as the patient 30. The pose (e.g., distance from a selected portion of the US probe 33 and / or the tracking device 81) may be determined or predetermined and saved for recall with a calibration process and / or jig, such as that disclosed in U.S. Pat. Nos. 7,831 ,082; 8,320,653; and 9,138,204, all incorporated herein by reference.

[0036] The imaging device 80 can be tracked with a tracking device 62. Also, the tracking device 81 can be associated directly with the US probe 33. The US probe 33 may, therefore, be directly tracked with a navigation system as discussed herein. In addition or alternatively, the US probe 33 may be positioned and tracked with the robotic system 20. Regardless, image data defining an image space acquired of the patient 30 can, according to various embodiments, be registered (e.g., manually, inherently, or automatically) relative to an object space. The object space can be the space defined by a patient 30 in the navigation system 26.

[0037] The patient 30 can also be tracked as the patient moves with a subject tracking device that may be variously referred to as a patient tracking device, DRF, or patient tracker 58. Alternatively, or in addition thereto, the patient 30 may be fixed within navigation space defined by the navigation system 26 to allow for registration. As discussed further herein, registration of the image space to the patient space or subject space allows for navigation of the instrument 68 with the image data. When navigating the instrument 68, a position of the instrument 68 can be illustrated relative to image data acquired of the patient 30 on a display device 84. An additional and / or alternative display device 84’ may also be present to display an image. Various tracking systems, such as one including an optical localizer 88 or an electromagnetic (EM) localizer 92 can be used to track the instrument 68.

[0038] More than one tracking system can be used to track the instrument 68 in the navigation system 26. According to various embodiments,these tracking systems can include an electromagnetic tracking (EM) system having the EM localizer 94, an optical tracking system having the optical localizer 88 and / or other appropriate tracking systems not illustrated such as an ultrasound tracking system, or other appropriate tracking systems. One or more of the tracking systems can be used to track selected tracking devices, as discussed herein, sequentially or simultaneously. It will be understood, unless discussed otherwise, that a tracking device can be a portion trackable with a selected tracking system. A tracking device need not refer to the entire member or structure to which the tracking device is affixed or associated.

[0039] Image data acquired from the imaging system 33, 80 or any appropriate imaging system, can be acquired at and / or forwarded from an image device controller 96, that may include a processor module 97, to a navigation computer and / or processor system 102 that can be a part of a controller or work station 98 having the display 84 and a user interface 106. The processor system 102 may be a processor module, as discussed herein, including integral memory or a communication system to access external memory for executing instructions and / or operated as a specific integrated circuit (e.g., ASIC). It will also be understood that the image data is not necessarily first retained in the controller 96, but may also be directly transmitted to the work station 98. The work station 98 can provide facilities for displaying the image data as an image 108 on the display 84, saving, digitally manipulating, or printing a hard copy image of the received image data. The user interface 106, which may be a keyboard, mouse, touch pen, touch screen or other suitable device, allows the user 72 to provide inputs to controlthe imaging device 80, via the image device controller 96, or adjust the display settings of the display 84. The work station 98 may also direct the image device controller 96 to adjust the image capturing portion of the imaging device 80 to obtain various two-dimensional images along different planes in order to generate one or more representative two-dimensional and three-dimensional image data that may be used to generate two-dimensional, three-dimensional, or a more than of either or both images.

[0040] With continuing reference to FIG. 1 , the navigation system 26 can further include any one or more tracking system, such as the tracking system including either or both of the electromagnetic (EM) localizer 94 and / or the optical localizer 88. The tracking systems may include a controller and interface portion 110. The controller 110 can be connected to the processor portion 102, which can include a processor included within a computer. The EM tracking system may include the STEALTHSTATION® AXIEM™ Navigation System, sold by Medtronic Navigation, Inc. having a place of business in Louisville, Colorado; or can be the EM tracking system described in U.S. Pat. No. 7,751 ,865; U.S. Pat. No. 5,983,126; U.S. Pat. No. 5,913,820; or U.S. Pat. No. 5,592,939; all of which are herein incorporated by reference. It will be understood that the navigation system 26 may also be or include any appropriate tracking system, including a STEALTHSTATION® TREON® or S7™ tracking systems having an optical localizer, which may be used as the optical localizer 88, and sold by Medtronic Navigation, Inc. having a place of business in Colorado. Other tracking systems include one or more tracking modalities, such as acoustic, radiation, radar, etc.The navigation system 26 and / or tracking system may be a hybrid system that includes components from multiple tracking systems. The tracking systems can be used according to generally known or described techniques in the above incorporated references. Details will not be included herein except to clarify selected operation of the subject disclosure.

[0041] Various portions of the navigation system 26, such as the instrument 68, and others as will be described in detail below, can be equipped with at least one, and generally multiple, of the tracking devices 66. The instrument can also include more than one type or modality of tracking device 66, such as an EM tracking device and / or an optical tracking device. According to various embodiments, the navigation system 26 can be used to track the instrument 68 relative to the patient 30. The instrument 68 can be tracked with the tracking system, as discussed above. Image data of the patient 30, or an appropriate subject, can be used to assist the user 72 in guiding the instrument 68. The image data, which may include one or more image data or images, may be registered to the patient 30. The image data defines an image space that is registered to the patient space defined by the patient 30. The registration can be performed as discussed herein, automatically, manually, or combinations thereof.

[0042] Generally, registration allows a translation map to be generated of the physical location of the instrument 68 relative to the image space of the image data. The translation map allows the tracked position of the instrument 68 to be displayed on the display device 84 relative to the image 108.A graphical representation 68i, also referred to as an icon, can be used to illustrate the location of the instrument 68 relative to the image data 108.

[0043] With continuing reference to Fig. 1 , a subject registration system or method can use the tracking device 58. The tracking device 58 may include portions or members 120 that may be trackable, but may also act as or be operable as a fiducial assembly. It is understood that the configuration of the tracker 58 may be any appropriate configuration and relate to the navigation system in use, parameters of the subject 30 (e.g., tracking location, size), etc. The fiducial assembly 120 can include a clamp or other fixation portion 124 and the imageable fiducial body 120. It is understood, however, that the members 120 may be separate from the tracking device 58. The fixation portion 124 can be provided to fix any appropriate portion, such as a portion of the anatomy. As illustrated in Fig. 1 , the fiducial assembly 120 can be interconnected with a vertebra 126 and / or a portion of the vertebra 126 which may form a spine. In various embodiments, the connection may be to a spinous process, a head frame, etc.

[0044] The subject 30 may be imaged with the appropriate imaging system 80, as discussed above. Registration of the physical space or coordinate system defined by the subject 30 to the image space or coordinate system defined by image data (e.g., included in an image 108) may occur with the selected registration process. Registration processes include those discussed above and including one or more of the touchless registration assembly 150. The registration assemblies 150 may include appropriate assemblies such as an image capture portion, laser range finder, or other appropriate assemblies. In variousembodiments, for example, the registration assembly 150 may emit or receive a light beam or pulse 154 that may be reflected from one or more surfaces. The registration device 150 may include a three-dimensional scanner such as a known by one skilled in the art.

[0045] The surfaces scanned may include a surface 158 of the subject 30. The surface of the subject 158 may include skin or other tissues of the subject. Further, the patient tracker 58 may be associated with the subject 30 in a selected pose, such as fixed to a bony structure thereof including a skull 162. The patient tracker 58, therefore, may be fixed relative to various portions of the subject 30 such as the skin surface 158, an ear 166, a portion of one or more of an eye 168 of the subject including an outer corner 170 or other appropriate portions. The patient tracker 58 may be fixed relative to portions of the subject in an appropriate manner. Further, the tracker 58 may also have a surface that is scanned and be included in a scan by the registration assembly 150 and included in the data collected thereby, as discussed herein.

[0046] The registration assembly 150 may be moved relative to the subject 30. Therefore, the emitted and / or reflected beam or photons 154 may be received at a sensor within the registration assembly 150. The registration assembly 150 may be moved relative to the subject 30 in an appropriate movement and / or random movement and, therefore, may scan the subject 30 from a plurality of poses. As illustrated in Fig. 2, exemplary poses of the registration assembly 150 may be a first pose “a” and a second pose “b”. It is understood, however, that any appropriate number of poses may be used. Further, the navigation system 26may collect or receive the scan data of the subject 30 from the registration device 150. The navigation system 26 may understand or determine when an appropriate amount of scan data is acquired and notify the user 72 thereof. The user 72 may move the registration assembly 150 relative to the subject 30 in any appropriate manner to scan an appropriate portion of the subject 30. The registration assembly 150 may also be held and / or moved by the robotic system 20, such as automatically thereby including receiving movement instructions from the navigation system 26.

[0047] As the registration assembly 150 is moved relative to the subject 30, it may be tracked with a registration assembly tracker 174. The registration assembly tracker 174 may be tracked with any appropriate modality within the navigation system 26. Therefore, the pose of the registration assembly 150 may be determined by tracking the registration tracker 174. The pose of the registration assembly 150 may be determined relative to any appropriate point, such as a starting point, the patient tracker 58, or any appropriate origin. In various embodiments, for example, the patient tracker 58 may be tracked and the registration assembly tracker 174 may be tracked. The pose of the registration assembly 150 may be determined relative to the patient tracker 58. The registration assembly 150 therefore acquires scan data of the subject 30 at a tracked pose relative to the patient tracker 58. Further, the registration assembly 150 may collect scan data of the patient tracker 58 as well. Therefore, registration information may be acquired of the surface of the subject 158 and / or the patient tracker 58.

[0048] As discussed above, the registration device 150 may scan the subject 30 and the patient tracker 58. The scanner may determine a distance or three-dimensional pose between a sensor within the registration assembly 150 and the surface 158 of the subject 30 and / or the patient tracker 58. The distance may be used to determine one or more points 180 that may be defined on the surface 158 of the subject 30. Also, a tracker point 184 may be determined on the surface of the tracker 58. It is understood that a plurality of points may be determined such as at the corner of the eye 170, or other various anatomical features of the subject 30. Fig. 2 illustrates many of the points 180 that may be defined on the surface 158 of the subject 30 and / or points 184 defined by the tracker 58. It is understood that any appropriate number of points 180, 184 may be defined or determined on the subject 30 and / or the tracker or 58.

[0049] With continuing in reference to Fig. 2 and additional refence to Fig. 3, registration data 200 may include a point representation and the subject 30 and / or other portions such as the tracker 58. The points 180 defined on the surface of the subject 30 may be illustrated and / or determined in a physical space such as with the registration device 150 being tracked with the tracking device 174. The points 180, therefore, may define a point cloud of the three-dimensional surface of the subject 30. In various embodiments, a mesh 204 may also be defined between the points 180 and / or separate from the points 180. It is understood that the points 180 as a point cloud and / or the mesh 204 may be used to define the surface for registration to the image data in the image 108, as is understood by one skilled in the art. Therefore, the use of the points 180 and / orthe mesh 204 are merely exemplary and not limiting to the subject disclosure. Similarly, the points 184 of the patient tracker 58 may be determined and defined. A mesh 208 may also be determined between various points of the patient tracker 58. Therefore, points 184 and / or mesh 208 may also be used to define the three- dimensional surface of the patient tracker 58.

[0050] As is understood in the art, the patient tracker 58 may be positioned on the subject 30 to allow tracking of the subject 30 during a procedure. Therefore, the patient tracker 58 may not be present in the image 108 and / or may need to be registered relative to the subject 30 and / or the image 108. Therefore, the tracker 58 may be segmented and, therefore, the representation 200 may include a region of interest (ROI) 212 that may be defined by the user 72 and / or automatically by the system, such as the navigation system 26. The ROI 212 may include the patient tracker 58 in the representation 200. It is understood by one skilled in the art, that one or more ROIs may be defined automatically and / or by the user 72.

[0051] The ROI 212 may be segmented or identified for analysis. For example, identifying or determining the exact position of the patient tracker 58 in the scan space 200 from the registration device 150 allows for registration of the patient tracker 58 to the subject 30 and the point cloud or mesh defined thereby. Further, during a procedure the pose of the tracking device 58 relative to the subject 30 is useful for ensuring and / or maintaining registration.

[0052] To assist and / or allow determination of the pose of the tracking device 58, a model of the patient tracker 58 may be matched to the scanrepresentation 200 to identify the patient tracker 58 therein. For example, a patient tracker model 220 may be compared to a plurality of points in the representation 200, such as only in the ROI 212 and / or to assist in defining the ROI 212. The model 220 may be predetermined and / or recalled from a memory. The model may also be determined by tracking a probe relative to the tracker 58 that is tracked by the navigation system 26 to define parameters of the tracker 58 for the model 220. The model 220 may be moved over the representation 200 in a virtual environment to identify the patient tracker 58. Once an appropriate match is determined, such as by evaluating the points 184 or determining the points 184 the patient tracker, the patient tracker representation 58’ may be determined in the data 200. Therefore, the model 220 may be a model of the patient tracker 58, such as from a computer aided design or similar determination of a physical representation (including parameters thereof) of the patient tracker 58 in the virtual space.

[0053] The registration representation 200 may be the scan of the subject 30 and / or the patient tracker 58 produced by the registration device 150. The determination of the patient tracker representation 58’ may be made by matching the model 220 which may be recalled from a memory to a portion of the representation 200. This allows the patient tracker representation 58’ to be registered to the portions, such as the point cloud 180, of the subject 30. The representation 200 may then be registered to the image data or image 108.

[0054] Turning in reference Fig. 4, the subject 30 may be fixed in aStealth Station ® Vertek® head holding or biopsy assembly 230. The assembly230 may include various portions, such as a head fixation portion or arms 234 andan instrument holding portion 238. Further, a patient tracker holding portion or arm 242 may be provided. The patient tracker 58 may be fixed to the arm 242 which is assembled and may be fixed relative to the other portions of the Vertek® head holding or subject holding assembly 230. During a registration scanning process, the entire assembly 230, the subject 30, and the patient tracker 58 may be scanned with the registration assembly 150. Therefore, various portions, including the patient holder assembly 230, the tracker 58, and other portions may be identified in the registration scan or data, such as the data 200. Thus, rather than only segmenting or identifying the subject tracker 58 in the registration 200 other portions, such as a subject holding assembly may be identified and segmented therefrom. In various embodiments, the registration data 200 may include data relating to a surface of the subject 30, such as with the points 180, and other portions relative thereto such as the subject tracker 58, a patient holding assembly 230, or other portions. Thus, the registration information or data 200 may include information that allows for registration and identification of various portions relative to the subject 30 and / or the subject 30 either alone or together.

[0055] Once the registration assembly 150 is operated to generate the registration data 200, which may include the points or point cloud or mesh data, as discussed above, a registration to the image data may be performed. The registration may be performed in various manners such as that disclosed in the U.S. Patent Application Publication No. US 2022 / 0309690, incorporated herein by reference. The registration, however, may be performed according to any appropriate manner.

[0056] Generally, the registration scan data 200, which may also be referred to herein as a point cloud, may have various points identified therein that relate to the surface of the subject 30. The image data acquired of the subject 30 may have a surface also identified therein, such as by segmentation. For example, the image of the subject 108 may have the surface thereof identified to allow for comparison to the registration scan data 200. Based upon a matching and identification of points in both of the image data surface and the registration scan data 200, a registration may be made between the scan registration data 200 and the surface data and the image data 108. For example, a transformation may be generated between the points identified on the registration data 200 and in the image 108.

[0057] Accordingly, the registration scan data 200 may initially detect or determine the points 180 defining the subject surface. The points 180 may be identified substantially automatically by executing instructions with processor module, such as the processor module 102 of the navigation system 26. The determination of the points 180 may be based upon a segmentation of the scan data which may also be performed automatically and / or with the user 72. The points 180 may also be used to identify various anatomical features in the subject 30 in the registration scan data 200. The similar or same anatomical features may be identified in the image 108, according to any appropriate manner. For example, as discussed above, the outer corner of the eye 170 may be identified as a point in the registration scan data 200 as the point 170 and this point may be related or correlated and then registered to the same point in the image 108. The point in theimage 108 may be identified in any appropriate manner. Further, more than one point may be used to define a surface which may also be used for the registration. Therefore, the points 180 representing the subject may be registered to points in the image 108.

[0058] The DRF in the registration scan data 200 may be identified such as with the model 220, as discussed above. This may allow the pose of the DRF in the registration data 200 to be determined. Thus, the pose of the DRF and the registration data may be used to determine the pose of the DRF relative to the image 108 and may allow for maintaining the registration of the subject space to the image space during a navigated procedure by tracking the patient tracker 58. The points in the registration data 200 that are related to the DRF 58 may be identified with the model 220 that is compared to the registration data 200. Again, the identification of the patient tracker in the registration data 200 may be performed substantially automatically by executing instructions of the processor module, such as the processor module 102.

[0059] Further, registration of the registration data 200 to the image data 108 may be performed. The registration may be, in various embodiments, substantially automatic, by matching or translating the points into the registration data 200 to the points into the image 108. As discussed above, a surface of the image may be determined by identifying or segmenting the surface of the image 108.

[0060] The registration may then be performed by determining a map, such as referred to as a translation or transformation map, between theregistration data 200 and the image 108. The map may include a determination or translation or transform from each or all of the identified points in the registration data 200 (or a selected number thereof, such as selected anatomical features) to the image points that are related thereto or the same points. Thus, the coordinate system of the subject space determined within the registration data 200 may be translated to the coordinate space of the image 108. Following the registration, the tracked pose of the instrument 68 may be determined and illustrated relative to the image 108 such as by a graphical representation 68i, as discussed herein.

[0061] The registration of the subject space to the image space may have a selected or determinable accuracy or estimated error. As is understood by one skilled in the art, a threshold may be determined relative to the error value prior to navigating a procedure and / or confirming a quality of a registration. Accordingly, the estimated error may be determined of the registration based upon the registration data 200 to the image 108. Further, given the size of the volume or surface, such as a head of the subject 30, various regions may have different estimated errors. In various embodiments, an error that is below a threshold in a region of a procedure may allow for an acceptable registration even if an overall estimated error or in another region is greater than a threshold.

[0062] Turning to reference to Fig. 5, an error in registration may be displayed on a display device for viewing by the user 72. For example, the image 108 may be displayed on the display device 84. The image 108 may be displayed in a plurality of manners, such as in profile, anterior, or the like. Nevertheless, the display 84 with the image 108 may include additional information such as aregistration error estimation information. For example, an area or volume 240 maybe identified with a first color or identification. A second area or volume 244 may be identified with a second volume or color or indication. The first volume 240 may include a first value or first indication, such as being a green color. The second volume or area 244 may be a second color, such as yellow. The two colors may relate to differing error estimations. Further, a specific value may be identified regarding a particular direction, such as a superior-to-inferior direction 248. The estimated error may be for selected directions as well, such as an inferior to superior registration error identified by the arrow 248. Accordingly, the user may understand that an error in a particular direction, given the three-dimensional nature of the image 108, may be understood relative to a threshold. Thus, the user may have a graphical representation and / or a discrete value of an error estimation for different areas of the image 108 regarding the registration.

[0063] The error may be calculated substantially automatically by the navigation system, such as the processor 102 according to various techniques. The estimated error may then be displayed for the user 72 to understand the estimated error in a particular region or volume. Accordingly, if the region 240 includes an error that is below a selective threshold and the region 240 includes various features, such as an access or an insertion point region 252, the user 72 may understand that the registration is an appropriate registration for performing a procedure at that region. However, if the access point or other feature is within the region 244, the user 72 may understand that the error is greater than a selectedthreshold. In such an instance, the user may select to perform additional analysis, such as performing a second registration scan.

[0064] Error estimations may also be identified in other graphical representations, such as in slice data. For example, the image data 108 may include the three-dimensional renderings 238 displayed with the display device 84. Further two-dimensional images, such as slices or slices of renderings may also be displayed as two-dimensional images 260. The registration is understood to be a registration of the image data or image 108 to the subject 30. Therefore, if slice image data is acquired the registration is of the slice image data and / or the three- dimensional reconstructions to the subject 30.

[0065] The registration accuracy or error estimation may also be displayed relative to two-dimensional slices. For example, various portions of a slice may be outlined with a selected graphic or line, such as a first line 264, which may be a first color or type of line, such as having a first dash pattern. A second line 268 may also be displayed and include a different color or representation, such as a different dash pattern. Therefore, the error estimation may also be displayed on a two dimensional image, which may be a slice image data acquired at the subject 30.

[0066] Turning reference to Fig. 6, image 108 may be displayed on the display device 84 as a three-dimensional rendering 280. The three-dimensional rendering may include a surface information, such as a skin surface of the subject 30. Again, the registration may be the subject space to the image space, which may include a registration of the surface and interior of related image data.Therefore, an identification of an error estimation may be included as a coloring of the surface or other graphical representation that is altered in the generated image 280. For example, a first portion may have a first error estimation relative to a threshold, such as being below a threshold. The first portion 284 may include a graphical alteration of the skin surface on the image 280. For example, the skin surface may be colored a selected color, such as a green color, or a selected hash mark pattern. A second or other different area 288 may include a different color or a different hash mark pattern. For example, the second area or region 280 may be a yellow color. Therefore, a distinction between different areas on the surface of the image 280 may be displayed to the user 72 regarding the estimated error of the registration of the subject space to the image space.

[0067] The graphical representations displayed to the user 72 may allow the user 72 to understand the estimated error of a registration at any particular region or volume of the registered space. The graphical representations may also include values that may be displayed in each of the areas, such as a discrete value including less than 1 millimeter (mm) for the first region 284 and greater than 1mm for the second region 288. Further, an overall or total estimated error 290 may be displayed on the display device 84. For example, as illustrated in Fig. 6, the total estimated error may be 1 ,5mm. The total error 1 ,5mm may be a value relative to a selected threshold, such as 1 mm. However, the specific or localized estimated errors may be different than the total error for the entire registration. Thus, as illustrated in Fig. 6, if the error in a selected region is less than 1 mm, which is determined to be less than a selected threshold, a procedurein that region may occur as it has an estimated error below a selected threshold. The representation allows the user 72 to understand the specific estimated errors in different regions or regions of interest relative to the image 108 and / or the subject 32 to assist in performing a procedure on the subject 30. It is understood that the error values may be ranges and the specific values are merely exemplary. Further, different procedures or subject may have different thresholds and / or error values.

[0068] With continuing reference to the above and additional reference to Fig. 7, a process 310 is illustrated. The process 310 is a flowchart or process that may be incorporated into an algorithm which may be further incorporated into a program or instructions that may be executed by one or more processor modules, such as the processor module 102. Accordingly, it will be understood that the various portions of the process 310 may be performed substantially automatically by the processor module 102 or other appropriate processor module executing instructions. Therefore, while various input may be provided by the user 72, it is understood the process 310 may be performed substantially automatically and / or with input by user as appropriate.

[0069] The process 310 allows for the registration and determination of a registration error or estimated registration error, according to various embodiments. The registration may occur or be performed with the acquired registration data 200 to be registered to the image 108. A registration error or estimated registration error may be determined. The output error or estimated error may be displayed, such as with the display device 84. The process 310, therefore,may be a process for performing registration and / or determining or outputting the error or estimated error.

[0070] The process 310, therefore, may begin in start block 320. After beginning the process in block 320, image data may be acquired in block 324. Acquiring image data on block 324 may include acquiring image data of the subject 30 in any appropriate manner. For example, as discussed above, the imaging system 80 may be used to acquire image data of the subject 30. Further image data may be acquired of the subject with any appropriate imaging system that may be an alternative to the imaging system 80, and may be acquired at any appropriate time. Thus, the image data of the subject acquired in block 324 may be acquired during a procedure, prior to a procedure, or at any appropriate time for the process 310.

[0071] A determination of a surface of the acquired image data may be performed in block 328. The determination of the surface in block 328 may include a segmentation of the acquired image data. For example, a selected depth or image data feature may be used to define a surface and the image data may be segmented accordingly. It is understood, however, the segmentation of the image data in block 328 is not required and is only optional. Thus, the image data acquired in block 324 may be used in the process 310 without segmentation. The segmentation of a surface, such as determining a skin surface of the subject in the image data acquired from block 324 may assist in performing the registration as discussed further herein.

[0072] An acquisition of the registration data is made in block 334. The acquisition of the registration data in block 334 may include a surface scan such as a three-dimensional or volumetric surface scan of the subject 30. The surface scan may be performed with any appropriate system such as the registration assembly 150. The acquisition of the registration data may allow for the determination or identification of one or more points of the surface of the subject 30. For example, as discussed above, a point cloud or number of points may define the surface of the subject 30. Further or alternatively, a mesh may be generated to define the surface of the subject 30. The point cloud or mesh, or both, may be used to identify various points on the subject 30 and / or surfaces on the subject 30 to allow for registration with the acquired image data from block 324.

[0073] The acquired registration data may include data that is acquired in substantially touchless manner. Touchless registration data may include registration data that is acquired without contacting a portion of the subject with a physical element, such as a touch probe or other instrument. For example, as discussed above, the registration assembly 150 may emit and / or receive light (i.e. photons). Therefore, the acquisition of the registration data may be substantially touchless such as with the registration assembly 150 as discussed above.

[0074] After acquisition of the registration data, a segmentation of the registration data may occur in block 338. The segmentation of the registration data in block 338 is optional and is not required. According to various embodiments, however, as discussed above, various regions of interest may be identified in theregistration data and it may be segmented for various purposes. For example, the user 72 may identify a portion that may include the subject tracker 58. Therefore, the identification of the subject tracker may be limited to the segmented area. It is understood, however, that a segmentation of the acquired registration data in block 338 is not required.

[0075] After acquiring the registration data from block 334, an identification of the subject tracker in the acquired registration data may occur in block 342. In various embodiments, the determination or identification of the subject tracker may include comparing the registration data to the model 220 of the subject tracker. The comparison may include a stepwise comparison of the model 220 to the acquired registration data 200 to determine the portion (e.g., points) of the registration data that is / are inclusive of the subject tracker. Identifying the subject tracker may allow for a separation of the registration data and / or segmentation of the registration data to identify the portion of the subject data related to the subject 30 and to the subject tracker 58. Thus, the registration data acquired in block 334 may be identified or separated for various purposes, as discussed further herein. The identification of the subject tracker in the acquired registration data in block 342 may assist in the appropriate identification of the subject tracker.

[0076] The image data acquired in block 324 and the registration data acquired in block 334 may then be used to register the subject space to the image space in block 350. As discussed above, the registration may include a determination of a correlation between the image space and the subject or physicalspace. This correlation allows a transformation or translation map to be determined between the registration data and the image data. The transformation may include identification of surfaces or various portions, such as anatomical features, in both the acquired registration data from block 334 and the acquired image data and block 324. The registration may include or be performed with an appropriate number of points in both the acquired registration data and acquired image data that are determined to match or be at known same or similar poses. Thus, a transformation map is defined there between. With the registration, the coordinate system of the image data may be mapped to the coordinate system of the patient space and vice versa to allow for a correlation there between and an identification of the same pose or points in both coordinate systems.

[0077] The subject tracker may also be registered to the image data in block 354. The subject tracker may be identified in block 342, as discussed above. The registration of the acquired registration data to the image data allows for a registration of the subject space to the image space. Nevertheless, the subject tracker is also registered to the image data based upon the determined pose of the subject tracker to the subject in the acquired registration data. Identifying the subject tracker in the block 342 allows for determination of a pose of the subject that is relative to the subject in the acquired registration data. Therefore, the subject tracker may be registered to the image data in a relationship to the subject to allow for a maintaining of the registration during a procedure by tracking the subject tracker with the navigation system 26.

[0078] A registration of the subject space to the image space may occur in block 350 and a registration of the subject tracker to the space make her block 354. The two registrations 350, 354 may both include a registration error that may be based upon various tolerances. For example, the registration device 150 may acquire a distance or surface scan to a certain tolerance based upon the parameters of the registration assembly 150. Further, the acquired registration data from block 334 when identified to the model of the subject tracker block 342 may also have a certain error or tolerance given the parameters of the model of the subject tracker, the tolerance of the acquired registration data, and other parameters.

[0079] The registration, nevertheless, may be output in block 360. The output registration may then have a determination of an error or an error estimation in block 364. The error estimation may be based upon or determined in light of the various tolerances, as discussed above, and according to various methods. The determination of the error may be based upon various procedures, such as perturbing data, such as the acquired registration data. Various methods may be referred to or known in the art as Monte Carlo methods.

[0080] In various embodiments, in determining the error estimation block 364 the acquired registration data may be perturbed in a perturbation process. For example, each point may be randomly perturbed or a standard perturbation amount may be provided or applied to each acquired registration data point. The registration may then be performed again to determine or identify whether any change has occurred. If a change has occurred in the registrationpose, the amount of change may relate to an error estimation. In various embodiments, the perturbation may then be repeated, particularly if an error occurs, to determine a refinement of the error estimation. Thus, the process 310 may include an error estimation procedure, according to various embodiments to determine the error in block 364.

[0081] The error estimation may then be output in block 368. Outputting the error estimation may be output in any appropriate manner, including saving the error estimation, for further analysis. According to various embodiments, the error estimation may be displayed in block 372. As discussed above, the error estimation may be displayed on the display device 84 relative to the image 108 in an appropriate manner and / or according to vary this display technique. Thus, the user 72 may view the display and understand the estimated error.

[0082] The estimated error may then be used to assist in determining a procedure and / or completing a procedure or further operational steps. Accordingly, the process 310 may allow for the determination of an error estimation and may output the error estimation in an appropriate manner, such as that discussed above.

[0083] The process 310 may then end in block 376. It is understood that ending the procedure 310 in block 376 may not include ending a procedure entirely. For example, if the error estimation is greater than a threshold, the user 72 may determine to perform the acquisition with the registration data again or in an alternative manner. Further, if the error estimation is within a selected threshold,the user 72 may determine to perform a procedure on the subject 30. Nevertheless, the error may be determined, particularly in estimation thereof, to assist in performing a procedure on the subject 30 according to the process 310.

[0084] As discussed above, the error may be an overall error for the entire registration volume. In various embodiments, the error estimation may be for different or vary for different portions of the volume. Thus, the determined error may be a single value and / or include more than one value for different specific portions of the registration volume. In other words, the error estimation may be determined and / or displayed to assist in the user 72 identify an error in one or more portions of the subject for registration. The error may be displayed on (e.g. , relative to) or in particular regions, such as those selected by the user 72, regarding where a procedure is planned and / or for other purposes. Thus, the process 310 may allow the user 72 to understand whether error and a selected threshold may affect or may be deemed to affect an accuracy of a navigation. The process 310 may allow for determination and output of an estimated error for various registration techniques, such as a touchless registration technique as described above.

[0085] Examples

[0086] Example 1 - A method to determine an estimated registration error, comprising: acquiring an image data of the subject; acquiring a touchless registration data of the subject; identifying a subject tracker associated with the subject in the touchless registration data; correlating the touchless registration data and the acquired image data; correlating the identified subject tracker associated with the acquired image data; determining a registration of an image coordinatesystem and a subject coordinate system based on the correlation of the touchless registration data and the acquired image data and the identified subject tracker associated with the acquired image data; determining an estimated error of the registration; and outputting the determined estimated error of the registration relative to a threshold.

[0087] Example 2 - The method of Example 1 , further comprising: determining a surface in the acquired image data.

[0088] Example 3 - The method of Example 1 , further comprising: providing a touchless registration assembly to acquire surface information regarding the subject.

[0089] Example 4 - The method of Example 3, wherein acquiring the touchless registration data of the subject includes providing a touchless registration assembly to provide three-dimensional surface scan data of the subject.

[0090] Example 5 - The method of Example 1 , wherein acquiring the touchless registration data of the subject includes acquiring at least one of (i) a point cloud of a surface of the subject or (ii) a mesh of a surface of the subject.

[0091] Example 6 - The method of Example 1 , wherein identifying the subject tracker associated with the subject in the touchless registration data includes matching a model of the subject tracker to at least a portion of the acquired touchless registration data.

[0092] Example 7 - The method of Example 1 , further comprising: perturbing the acquired touchless registration data; correlating the perturbedacquired touchless registration data and the acquired image data; and determining a perturbed registration of the image coordinate system and the subject coordinate system based on the correlation of the perturbed touchless registration data and the acquired image data and the identified subject tracker associated with the acquired image data; determining an estimated error of the perturbed registration; and comparing the registration and the perturbed registration.

[0093] Example 8 - The method of Example 1 , further comprising: displaying an image based at least on the acquired image data; displaying the output determined estimated error of the registration relative to the threshold as a graphic illustration superimposed on the image.

[0094] Example 9 - The method of Example 1 , further comprising: displaying an image based at least on the acquired image data; displaying the output determined estimated error of the registration relative to the threshold as a surface marking of a surface of the image.

[0095] Example 10 - The method of Example 1 , further comprising: displaying an image based at least on the acquired image data; displaying the output determined estimated error of the registration relative to the threshold as a numerical value relative to the image.

[0096] Example 11 - The method of Example 1 , further comprising: displaying an image based at least on the acquired image data; wherein determining the estimated error of the registration includes at least a first estimated error of the registration regarding a first region of the image and a second estimated error of the registration regarding a second region of the image; whereinoutputting the determined estimated error includes outputting both the first estimated error of the registration and the second estimated error of the registration.

[0097] Example 12 - The method of Example 11 , further comprising: displaying the both the first estimated error of the registration and the second estimated error of the registration relative to the displayed image.

[0098] Example 13 - A system operable to determine an estimated registration error, comprising: a processor module configured to execute instructions to: acquire an image data of the subject; acquire a touchless registration data of the subject; identify a subject tracker associated with the subject in the touchless registration data; correlate the touchless registration data and the acquired image data; correlate the identified subject tracker associated with the acquired image data; determine a registration of an image coordinate system and a subject coordinate system based on the correlation of the touchless registration data and the acquired image data and the identified subject tracker associated with the acquired image data; determine an estimated error of the registration; and output the determined estimated error of the registration relative to a threshold; and a communication system to communicate the output determined estimated error of the registration relative to the threshold.

[0099] Example 14 - The system of Example 13, further comprising: a touchless registration assembly including a sensor to determine a distance to a surface of the subject; and a touchless registration assembly tracking device to track a pose of the touchless registration assembly.

[0100] Example 15 - The system of Example 14, further comprising: a subject tracker configured to be associated with the subject and included in the in the touchless registration data; wherein identify the subject tracker associated with the subject in the touchless registration data includes matching a model of the subject tracker to at least a portion of the acquired touchless registration data.

[0101] Example 16 - The system of Example 13, further comprising: a display device configured to display both (i) an image based at least on the acquired image data and (ii) at least one of (1) the output determined estimated error of the registration relative to the threshold as a graphic illustration superimposed on the image, (2) the output determined estimated error of the registration relative to the threshold as a surface marking of a surface of the image, or (3) the output determined estimated error of the registration relative to the threshold as a numerical value relative to the image.

[0102] Example 17 - The system of Example 13, further comprising: the processor module configured to execute further instructions wherein the determined estimated error of the registration includes at least a first estimated error of the registration regarding a first region of the image and a second estimated error of the registration regarding a second region of the image.

[0103] Example 18 - The system of Example 17, further comprising: a display device configured to display both (i) an image based at least on the acquired image data and (ii) both the first estimated error of the registration and the second estimated error of the registration.

[0104] Example 19 - The system of Example 14, further comprising: a tracking system configured to track both a subject tracker and the touchless registration assembly tracking device.

[0105] Example 20 - The system of Example 13, further comprising: an imaging system configured to acquire the image data of the subject.

[0107] Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0108] Instructions may be executed by a processor and may include software, firmware, and / or microcode, and may refer to programs, routines, functions, classes, data structures, and / or objects. The term shared processor circuit encompasses a single processor circuit that executes some or all code from multiple modules. The term group processor circuit encompasses a processor circuit that, in combination with additional processor circuits, executes some or all code from one or more modules. References to multiple processor circuits encompass multiple processor circuits on discrete dies, multiple processor circuits on a single die, multiple cores of a single processor circuit, multiple threads of a single processor circuit, or a combination of the above. The term shared memory circuit encompasses a single memory circuit that stores some or all code from multiple modules. The term group memory circuit encompasses a memory circuit that, in combination with additional memories, stores some or all code from one or more modules.

[0109] The apparatuses and methods described in this application may be partially or fully implemented by a processor (also referred to as a processor module) that may include a special purpose computer (i.e., created by configuring a processor) and / or a general purpose computer to execute one or more particular functions embodied in computer programs. The computer programs include processor-executable instructions that are stored on at least one non-transitory, tangible computer-readable medium. The computer programs may also include or rely on stored data. The computer programs may include a basic input / output system (BIOS) that interacts with hardware of the special purpose computer, device drivers that interact with particular devices of the special purpose computer, one or more operating systems, user applications, background services and applications, etc.

[0110] The computer programs may include: (i) assembly code; (ii) object code generated from source code by a compiler; (iii) source code for execution by an interpreter; (iv) source code for compilation and execution by a just-in-time compiler, (v) descriptive text for parsing, such as HTML (hypertext markup language) or XML (extensible markup language), etc. As examples only, source code may be written in C, C++, C#, Objective-C, Haskell, Go, SQL, Lisp, Java®, ASP, Perl, Javascript®, HTML5, Ada, ASP (active server pages), Perl, Scala, Erlang, Ruby, Flash®, Visual Basic®, Lua, or Python®.

[0111] Communications may include wireless communications described in the present disclosure can be conducted in full or partial compliance with IEEE standard 802.11-2012, IEEE standard 802.16-2009, and / or IEEEstandard 802.20-2008. In various implementations, IEEE 802.11-2012 may be supplemented by draft IEEE standard 802.11ac, draft IEEE standard 802.11ad, and / or draft IEEE standard 802.11 ah.

[0112] A processor, processor module, module or ‘controller’ may be used interchangeably herein (unless specifically noted otherwise) and each may be replaced with the term ‘circuit.’ Any of these terms may refer to, be part of, or include: an Application Specific Integrated Circuit (ASIC); a digital, analog, or mixed analog / digital discrete circuit; a digital, analog, or mixed analog / digital integrated circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor circuit (shared, dedicated, or group) that executes code; a memory circuit (shared, dedicated, or group) that stores code executed by the processor circuit; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system-on- chip.

[0113] Instructions may be executed by one or more processors or processor modules, such as one or more digital signal processors (DSPs), general purpose microprocessors, application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Accordingly, the term “processor” or “processor module” as used herein may refer to any of the foregoing structure or any other physical structure suitable for implementation of the described techniques. Also, the techniques could be fully implemented in one or more circuits or logic elements.

[0114] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Claims

CLAIMSWhat is claimed is:

1. A method to determine an estimated registration error, comprising: acquiring an image data of the subject; acquiring a touchless registration data of the subject; identifying a subject tracker associated with the subject in the touchless registration data; correlating the touchless registration data and the acquired image data; correlating the identified subject tracker associated with the acquired image data; determining a registration of an image coordinate system and a subject coordinate system based on the correlation of the touchless registration data and the acquired image data and the identified subject tracker associated with the acquired image data; determining an estimated error of the registration; and outputting the determined estimated error of the registration relative to a threshold.

2. The method of Claim 1 , further comprising: determining a surface in the acquired image data.

3. The method of Claim 1 , further comprising: providing a touchless registration assembly to acquire surface information regarding the subject.

4. The method of Claim 3, wherein acquiring the touchless registration data of the subject includes providing a touchless registration assembly to provide three-dimensional surface scan data of the subject.

5. The method of Claim 1 , wherein acquiring the touchless registration data of the subject includes acquiring at least one of (i) a point cloud of a surface of the subject or (ii) a mesh of a surface of the subject.

6. The method of Claim 1 , wherein identifying the subject tracker associated with the subject in the touchless registration data includes matching a model of the subject tracker to at least a portion of the acquired touchless registration data.

7. The method of Claim 1 , further comprising: perturbing the acquired touchless registration data; correlating the perturbed acquired touchless registration data and the acquired image data; and determining a perturbed registration of the image coordinate system and the subject coordinate system based on the correlation of the perturbedtouchless registration data and the acquired image data and the identified subject tracker associated with the acquired image data; determining an estimated error of the perturbed registration; and comparing the registration and the perturbed registration.

8. The method of Claim 1 , further comprising: displaying an image based at least on the acquired image data; displaying the output determined estimated error of the registration relative to the threshold as a graphic illustration superimposed on the image.

9. The method of Claim 1 , further comprising: displaying an image based at least on the acquired image data; displaying the output determined estimated error of the registration relative to the threshold as a surface marking of a surface of the image.

10. The method of Claim 1 , further comprising: displaying an image based at least on the acquired image data; displaying the output determined estimated error of the registration relative to the threshold as a numerical value relative to the image.11 . The method of Claim 1 , further comprising: displaying an image based at least on the acquired image data;wherein determining the estimated error of the registration includes at least a first estimated error of the registration regarding a first region of the image and a second estimated error of the registration regarding a second region of the image; wherein outputting the determined estimated error includes outputting both the first estimated error of the registration and the second estimated error of the registration.

12. A system operable to determine an estimated registration error, comprising: a processor module configured to execute instructions to: acquire an image data of the subject; acquire a touchless registration data of the subject; identify a subject tracker associated with the subject in the touchless registration data; correlate the touchless registration data and the acquired image data; correlate the identified subject tracker associated with the acquired image data; determine a registration of an image coordinate system and a subject coordinate system based on the correlation of the touchless registration data and the acquired image data and the identified subject tracker associated with the acquired image data;determine an estimated error of the registration; and output the determined estimated error of the registration relative to a threshold; and a communication system to communicate the output determined estimated error of the registration relative to the threshold.

13. The system of Claim 12, further comprising: a display device configured to display both (i) an image based at least on the acquired image data and (ii) at least one of (1) the output determined estimated error of the registration relative to the threshold as a graphic illustration superimposed on the image, (2) the output determined estimated error of the registration relative to the threshold as a surface marking of a surface of the image, or (3) the output determined estimated error of the registration relative to the threshold as a numerical value relative to the image.

14. The system of Claim 12, further comprising: the processor module configured to execute further instructions wherein the determined estimated error of the registration includes at least a first estimated error of the registration regarding a first region of the image and a second estimated error of the registration regarding a second region of the image; a display device configured to display both (i) an image based at least on the acquired image data and (ii) both the first estimated error of the registration and the second estimated error of the registration.

15. The system of Claim 12, further comprising: a touchless registration assembly including a sensor to determine a distance to a surface of the subject; and a touchless registration assembly tracking device to track a pose of the touchless registration assembly; and a tracking system configured to track both a subject tracker and the touchless registration assembly tracking device.

Images