Patient registration using stereovision

Abstract

Systems and methods for performing a patient registration using active stereovision are provided. One or more first images may be received and at least one object may be identified in each of the first images. A pose of each object and a boundary on a mask positioned on a projector may be determined. A portion of the mask within the boundary may block a corresponding portion of the projector. One or more second images may be received and the at least one object and a patient may be identified in each of the second images. A first coordinate system and a second coordinate system may each be registered to a third coordinate system. A transformation may be determined to correlate the first coordinate system with the second coordinate system based on the registration of the first coordinate system and the second coordinate system.

Description

PATIENT REGISTRATION USING STEREO VISIONCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of and priority to U.S. Provisional Patent Application No. 63 / 536,173 filed 1 September 2023. The entire disclosure of which is incorporated by reference herein.BACKGROUND

[0002] The present disclosure is generally directed to image registration, and relates more particularly to registration using stereo image data.

[0003] Surgical robots may assist a surgeon or other medical provider in carrying out a surgical procedure, or may complete one or more surgical procedures autonomously. Imaging may be used by a medical provider for diagnostic and / or therapeutic purposes. Patient anatomy can change over time, particularly following placement of a medical implant in the patient anatomy.BRIEF SUMMARY

[0004] Example aspects of the present disclosure include:

[0005] A system according to at least one embodiment of the present disclosure comprises a processor; and a memory coupled to the processor and storing data thereon that, when processed by the processor, enables the processor to: receive one or more first images; identify at least one object in each of the first images; determine a pose of each object; determine a boundary on a mask positioned on a projector, the boundary corresponding to an outline of the at least one object; cause a portion of the mask within the boundary to block a corresponding portion of the projector; receive one or more second images; identify the at least one image and a patient in each of the second images; register a first coordinate system to a third coordinate system; register a second coordinate system to a third coordinate system; and determine a transformation to correlate the first coordinate system with the second coordinate system based on the registration of the first coordinate system and the registration of the second coordinate system.

[0006] Any of the aspects herein, wherein the memory stores further data for processing by the processor that, when processed, enables the processor to: turn the projector on.

[0007] Any of the aspects herein, wherein the one or more first images are received when the projector is turned off and the one or more second images are received when the projector is turned on.

[0008] Any of the aspects herein, wherein the first coordinate system comprises a coordinate system of the patient, the second coordinate system comprises a coordinate system of the object, and the third coordinate system comprises a coordinate system of an imaging device.

[0009] Any of the aspects herein, further comprising: an imaging device configured to obtain the one or more first images and the one or more second images.

[0010] Any of the aspects herein, wherein the imaging device comprises a stereo camera.

[0011] Any of the aspects herein, wherein the one or more first images comprises images without a pattern and the one or more second images comprises images with a pattern and a portion of the pattern blocked by the portion of the mask within the boundary.

[0012] Any of the aspects herein, wherein the pattern comprises a plurality of dots.

[0013] Any of the aspects herein, wherein the imaging device is supported by at least one of a stand, a user, or a robotic arm.

[0014] Any of the aspects herein, wherein the mask comprises a liquid crystal display (LCD) on which each pixel can be controlled, and wherein pixels within the boundary on the LCD are blacked out.

[0015] A system according to at least one embodiment of the present disclosure comprises an imaging device; a projector configured to project a pattern; a mask configured to block at least a portion of the projector; a processor; and a memory coupled to the processor and storing data thereon that, when processed by the processor, enables the processor to: receive one or more first images from the imaging device; identify at least one object in each of the first images; determine a pose of each object; determine a boundary on a mask positioned on a projector, the boundary corresponding to the at least one object; cause a portion of the mask within the boundary to block a corresponding portion of the projector; receive one or more second images from the imaging device; register a first coordinate system with a third coordinate system; register a second coordinate system with the third coordinate system; and determine a transformation to correlate the first coordinate system with the second coordinate system based on the registration of the first coordinate system and the registration of the second coordinate system.

[0016] Any of the aspects herein, wherein the memory stores further data for processing by the processor that, when processed, enables the processor to: turn the projector on.

[0017] Any of the aspects herein, wherein the one or more first images are received when the projector is turned off and the one or more second images are received when the projector is turned on.

[0018] Any of the aspects herein, wherein the first coordinate system comprises a coordinate system of the patient, the second coordinate system comprises a coordinate system of the object, and the third coordinate system comprises a coordinate system of an imaging device.

[0019] Any of the aspects herein, wherein the imaging device comprises a stereo camera.

[0020] Any of the aspects herein, wherein the one or more first images comprises images without a pattern and the one or more second images comprises images with a pattern and a portion of the pattern blocked by the portion of the mask within the boundary.

[0021] Any of the aspects herein, wherein the pattern comprises a plurality of dots.

[0022] Any of the aspects herein, wherein the imaging device is supported by at least one of a stand, a user, or a robotic arm.

[0023] Any of the aspects herein, wherein the mask comprises a liquid crystal display (LCD) on which each pixel can be controlled, and wherein pixels within the boundary on the LCD are blacked out.

[0024] A system according to at least one embodiment of the present disclosure comprises a stereo camera; a projector configured to project a pattern onto a patient; an LCD positioned on the projector and configured to block at least a portion of the projector; a processor; and a memory coupled to the processor and storing data thereon that, when processed by the processor, enables the processor to:

[0025] receive one or more first images from the stereo camera; identify a reference marker disposed on the patient in each of the first images; determine a pose of the reference marker; determine a boundary on the LCD corresponding to an outline of the reference marker; cause a portion of the LCD within the boundary to block a corresponding portion of the projector; receive one or more second images from the stereo camera; identify the patient and the reference marker in each of the second images register a patient coordinate system to an imaging device coordinate system; register a reference frame coordinate system to the imaging device coordinate system; and determine a transformation to correlate the patient coordinate system with the reference frame coordinate system based on the registration of the patient coordinate system and the registration of the reference frame coordinate system.

[0026] Any aspect in combination with any one or more other aspects.

[0027] Any one or more of the features disclosed herein.

[0028] Any one or more of the features as substantially disclosed herein.

[0029] Any one or more of the features as substantially disclosed herein in combination with any one or more other features as substantially disclosed herein.

[0030] Any one of the aspects / features / embodiments in combination with any one or more other aspects / features / embodiments.

[0031] Use of any one or more of the aspects or features as disclosed herein.

[0032] It is to be appreciated that any feature described herein can be claimed in combination with any other feature(s) as described herein, regardless of whether the features come from the same described embodiment.

[0033] The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the techniques described in this disclosure will be apparent from the description and drawings, and from the claims.

[0034] The phrases “at least one”, “one or more”, and “and / or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and / or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together. When each one of A, B, and C in the above expressions refers to an element, such as X, Y, and Z, or class of elements, such as XI -Xn, Yl- Ym, and Zl-Zo, the phrase is intended to refer to a single element selected from X, Y, and Z, a combination of elements selected from the same class (e.g., XI and X2) as well as a combination of elements selected from two or more classes (e.g., Y 1 and Zo).

[0035] The term “a” or “an” entity refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, and “having” can be used interchangeably.

[0036] The preceding is a simplified summary of the disclosure to provide an understanding of some aspects of the disclosure. This summary is neither an extensive nor exhaustive overview of the disclosure and its various aspects, embodiments, and configurations. It is intended neither to identify key or critical elements of the disclosure nor to delineate the scope of the disclosure but to present selected concepts of the disclosure in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other aspects, embodiments, and configurations of the disclosure are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.

[0037] Numerous additional features and advantages of the present disclosure will become apparent to those skilled in the art upon consideration of the embodiment descriptions provided hereinbelow.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0038] The accompanying drawings are incorporated into and form a part of the specification to illustrate several examples of the present disclosure. These drawings, together with the description, explain the principles of the disclosure. The drawings simply illustrate preferred and alternative examples of how the disclosure can be made and used and are not to be construed as limiting the disclosure to only the illustrated and described examples. Further features and advantages will become apparent from the following, more detailed, description of the various aspects, embodiments, and configurations of the disclosure, as illustrated by the drawings referenced below.

[0039] Fig. 1 is a block diagram of a system according to at least one embodiment of the present disclosure;

[0040] Fig. 2 shows additional aspects of the system according to at least one embodiment of the present disclosure;

[0041] Fig. 3 is a schematic diagram of a system according to at least one embodiment of the present disclosure;

[0042] Fig. 4A is an image of a patient registration according to at least one embodiment of the present disclosure;

[0043] Fig. 4B is an image of a patient registration according to at least one embodiment of the present disclosure;

[0044] Fig. 4C is an image of a patient registration according to at least one embodiment of the present disclosure; and

[0045] Fig. 5 is a flowchart according to at least one embodiment of the present disclosure.DETAILED DESCRIPTION

[0046] It should be understood that various aspects disclosed herein may be combined in different combinations than the combinations specifically presented in the description and accompanying drawings. It should also be understood that, depending on the example or embodiment, certain acts or events of any of the processes or methods described herein may be performed in a different sequence, and / or may be added, merged, or left out altogether (e.g., all described acts or events may not be necessary to carry out the disclosed techniques according to differentembodiments of the present disclosure). In addition, while certain aspects of this disclosure are described as being performed by a single module or unit for purposes of clarity, it should be understood that the techniques of this disclosure may be performed by a combination of units or modules associated with, for example, a computing device and / or a medical device.

[0047] In one or more examples, the described methods, processes, and techniques may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored as one or more instructions or code on a computer-readable medium and executed by a hardware -based processing unit. Alternatively or additionally, functions may be implemented using machine learning models, neural networks, artificial neural networks, or combinations thereof (alone or in combination with instructions). Computer- readable media may include non-transitory computer-readable media, which corresponds to a tangible medium such as data storage media (e.g., RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer).

[0048] Instructions may be executed by one or more processors, such as one or more digital signal processors (DSPs), general purpose microprocessors (e.g., Intel Core i3, i5, i7, or i9 processors; Intel Celeron processors; Intel Xeon processors; Intel Pentium processors; AMD Ryzen processors; AMD Athlon processors; AMD Phenom processors; Apple A10 or 10X Fusion processors; Apple Al 1, A 12, A12X, A12Z, or A13 Bionic processors; or any other general purpose microprocessors), graphics processing units (e.g., Nvidia GeForce RTX 2000-series processors, Nvidia GeForce RTX 3000-series processors, AMD Radeon RX 5000-series processors, AMD Radeon RX 6000-series processors, or any other graphics processing units), application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Accordingly, the term “processor” 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.

[0049] Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or“having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Further, the present disclosure may use examples to illustrate one or more aspects thereof. Unless explicitly stated otherwise, the use or listing of one or more examples (which may be denoted by “for example,” “by way of example,” “e.g.,” “such as,” or similar language) is not intended to and does not limit the scope of the present disclosure.

[0050] The terms proximal and distal are used in this disclosure with their conventional medical meanings, proximal being closer to the operator or user of the system, and further from the region of surgical interest in or on the patient, and distal being closer to the region of surgical interest in or on the patient, and further from the operator or user of the system.

[0051] Prior to or during a surgical procedure, patient registration may be performed. One way to perform patient registration using a stereo imaging system is to register both the patient anatomy and a navigation reference frame in the common coordinate frame of the imaging system. To register the patient anatomy, geometric features as determined by the stereo imaging system are aligned with geometric features present in a medical image of the anatomy and the same can be done for the reference frame. However, an optical target may be used on the reference frame such as a checkerboard, an aruco marker, a QR code, etc. increase an accuracy of registering the reference frame. The corners of these targets can be identified in the stereo images with sub-pixel resolution leading to very accurate and reproducible 3D registration. A challenge arises when attempting to register the patient anatomy and an optical target simultaneously. Stereo imaging systems rely on texture to identify corresponding pixels in the left and right stereo image pairs. The patient's anatomy typically does not contain enough texture to accurately perform stereo matching. It is common, then, to project a laser dot pattern onto the patient to add an artificial texture to the image and dramatically improve the accuracy of the scan. This is commonly referred to as "active stereo." The problem is the laser dot pattern tends to corrupt or obscure the image of the optical target.

[0052] There are a couple of approaches to solving this issue. For example, two snapshots can be taken to perform registration - one with the dot pattern on and the other with the dot pattern off. However, for handheld applications this is not ideal as the stereo camera may move between the two acquisition and the images will no longer be in the same coordinate system. Another approach would be to add another pair of cameras that cannot see the dot pattern. An example would be using an infrared (IR) dot projector and adding two cameras with infrared filters. The cameras with infrared filters would register the optical target, while the cameras without the IRfilters would be responsible for registering the patient anatomy. This solves the simultaneity problem, but is fairly costly and requires a more intricate calibration of a four camera system.

[0053] At least one embodiment according to the present disclosure includes using a mask such as a two-dimensional (2D) liquid crystal display (LCD) array in front of the dot projector to block the dot pattern at the location of the optical target or reference frame. In such embodiments, the registration process would begin with the projector off, and the position of the optical target is determined. The outline of the target could then be projected onto the LCD panel to determine which pixels to black out or otherwise block the dot patten within the boundary. Some margin could be added to account for motion of the camera. Finally, the dot projector is turned on along with the LCD panel and a pair of images are acquired where the patient anatomy contains texture from the dot pattern while the optical target is in shadow and the fiducials are clearly visible. Such registration - which is beneficially touchless - can improve surgical workflow and navigation accuracy. Combining optical targets on a navigation reference frame with an active stereo imaging system could significantly improve accuracy and or reduce patient registration time.

[0054] Embodiments of the present disclosure provide technical solutions to one or more of the problems of (1) registration of both a patient and a reference marker using an optical target, (2) improving an accuracy of using a handheld imaging device for registration, and (3) improving touchless registration.

[0055] Turning first to Fig. 1, a block diagram of a system 100 according to at least one embodiment of the present disclosure is shown. The system 100 may be used to register or correlate one or more coordinate systems with each other and / or carry out one or more other aspects of one or more of the methods disclosed herein. The system 100 comprises a computing device 102, one or more imaging devices 112, a projector 136, a robot 114, a navigation system 118, a database 130, and / or a cloud or other network 134. Systems according to other embodiments of the present disclosure may comprise more or fewer components than the system 100. For example, the system 100 may not include the robot 114, one or more components of the computing device 102, the database 130, and / or the cloud 134.

[0056] The computing device 102 comprises a processor 104, a memory 106, a communication interface 108, and a user interface 110. Computing devices according to other embodiments of the present disclosure may comprise more or fewer components than the computing device 102.

[0057] The processor 104 of the computing device 102 may be any processor described herein or any similar processor. The processor 104 may be configured to execute instructions stored in thememory 106, which instructions may cause the processor 104 to carry out one or more computing steps utilizing or based on data received from the imaging device 112, the projector 136, the robot 114, the navigation system 118, the database 130, and / or the cloud 134.

[0058] The memory 106 may be or comprise RAM, DRAM, SDRAM, other solid-state memory, any memory described herein, or any other tangible, non-transitory memory for storing computer-readable data and / or instructions. The memory 106 may store information or data useful for completing, for example, any step of the method 500 described herein, or of any other methods. The memory 106 may store, for example, instructions and / or machine learning models that support one or more functions of the projector 136 and / or the imaging device 112. For instance, the memory 106 may store content (e.g., instructions and / or machine learning models) that, when executed by the processor 104, enable image processing 120, a segmentation 122, a registration 124, and / or a transformation 128.

[0059] The image processing 120 enables the processor 104 to process image data of an image (received from, for example, the imaging device 112, an imaging device of the navigation system 118, or any imaging device) for the purpose of, for example, identifying information about a patient and / or an object such as a reference marker 140 depicted in the image. The information may comprise, for example, a pose of the patient, a pose of the reference marker 140, a boundary of the reference marker 140, etc. The information obtained from the image processing 120 may enable, for example, determining a boundary on a mask such as a mask 138 (described in more detail below) corresponding to the reference marker 140. The information may also enable registration of the patient to a common coordinate frame of the imaging device 112, and / or registration of the reference marker 140 to the common coordinate frame of the imaging device 112. The image processing 120 may use segmentation 122 to identify the patient and / or the one or more objects, as described below.

[0060] The segmentation 122 enables the processor 104 to segment the image data so as to identify the patient and / or one or more objects such as, for example, the reference marker 140 in the image data. The segmentation 122 may enable the processor 104 to identify a boundary of an object or the patient by using, for example, feature recognition. For example, the segmentation 122 may enable the processor 104 to identify the patient’s head in the image data. In other instances, the segmentation 122 may enable the processor 104 to identify a boundary of an object (e.g., the reference marker 140) by determining a difference in or contrast between colors or grayscales of image pixels.

[0061] The registration 124 enables the processor 104 to correlate one coordinate system with another coordinate system. For example, the registration 124 may enable the processor 104 to correlate or map a first coordinate system (e.g., a patient coordinate system) with a third coordinate system (e.g., an imaging device coordinate system) and a second coordinate system (e.g., a reference frame coordinate system) with the third coordinate system (e.g., the imaging device coordinate system).

[0062] The transformation 128 enables the processor 104 to transform one coordinate system into another coordinate system. In other words, the transformation 128 enables the processor 104 to transform the first coordinate system (e.g., the patient coordinate system) into the second coordinate system (e.g., the reference frame coordinate system) based on, for example, the registration of the first coordinate system and the third coordinate system and the registration of the second coordinate system and the third coordinate system.

[0063] Such content, if provided as in instruction, may, in some embodiments, be organized into one or more applications, modules, packages, layers, or engines. Alternatively or additionally, the memory 106 may store other types of content or data (e.g., machine learning models, artificial neural networks, deep neural networks, etc.) that can be processed by the processor 104 to carry out the various method and features described herein. Thus, although various contents of memory 106 may be described as instructions, it should be appreciated that functionality described herein can be achieved through use of instructions, algorithms, and / or machine learning models. The data, algorithms, and / or instructions may cause the processor 104 to manipulate data stored in the memory 106 and / or received from or via the imaging device 112, the projector 136, the robot 114, the database 130, and / or the cloud 134.

[0064] The computing device 102 may also comprise a communication interface 108. The communication interface 108 may be used for receiving image data or other information from an external source (such as the imaging device 112, the projector 136, the robot 114, the navigation system 118, the database 130, the cloud 134, and / or any other system or component not part of the system 100), and / or for transmitting instructions, images, or other information to an external system or device (e.g., another computing device 102, the imaging device 112, the projector 136, the robot 114, the navigation system 118, the database 130, the cloud 134, and / or any other system or component not part of the system 100). The communication interface 108 may comprise one or more wired interfaces (e.g., a USB port, an Ethernet port, a Firewire port) and / or one or more wireless transceivers or interfaces (configured, for example, to transmit and / or receive information via one or more wireless communication protocols such as 802.1 la / b / g / n,Bluetooth, NFC, ZigBee, and so forth). In some embodiments, the communication interface 108 may be useful for enabling the device 102 to communicate with one or more other processors 104 or computing devices 102, whether to reduce the time needed to accomplish a computingintensive task or for any other reason.

[0065] The computing device 102 may also comprise one or more user interfaces 110. The user interface 110 may be or comprise a keyboard, mouse, trackball, monitor, television, screen, touchscreen, and / or any other device for receiving information from a user and / or for providing information to a user. The user interface 110 may be used, for example, to receive a user selection or other user input regarding any step of any method described herein. Notwithstanding the foregoing, any required input for any step of any method described herein may be generated automatically by the system 100 (e.g., by the processor 104 or another component of the system 100) or received by the system 100 from a source external to the system 100. In some embodiments, the user interface 110 may be useful to allow a surgeon or other user to modify instructions to be executed by the processor 104 according to one or more embodiments of the present disclosure, and / or to modify or adjust a setting of other information displayed on the user interface 110 or corresponding thereto.

[0066] Although the user interface 110 is shown as part of the computing device 102, in some embodiments, the computing device 102 may utilize a user interface 110 that is housed separately from one or more remaining components of the computing device 102. In some embodiments, the user interface 110 may be located proximate one or more other components of the computing device 102, while in other embodiments, the user interface 110 may be located remotely from one or more other components of the computer device 102.

[0067] The imaging device 112 may be operable to image anatomical feature(s) (e.g., a bone, veins, tissue, etc.) and / or other aspects of patient anatomy to yield image data (e.g., image data depicting or corresponding to a bone, veins, tissue, etc.). “Image data” as used herein refers to the data generated or captured by an imaging device 112, including in a machine-readable form, a graphical / visual form, and in any other form. In various examples, the image data may comprise data corresponding to an anatomical feature of a patient, or to a portion thereof or an object such as the reference marker 140. The image data may be or comprise a preoperative image, an intraoperative image, a postoperative image, or an image taken independently of any surgical procedure.

[0068] The imaging device 112 may be capable of taking a 2D image or a 3D image to yield the image data. The imaging device 112 may be or comprise, for example, an ultrasound scanner(which may comprise, for example, a physically separate transducer and receiver, or a single ultrasound transceiver), an O-arm, a C-arm, a G-arm, or any other device utilizing X-ray-based imaging (e.g., a fluoroscope, a CT scanner, or other X-ray machine), a magnetic resonance imaging (MRI) scanner, an optical coherence tomography (OCT) scanner, an endoscope, a microscope, an optical camera, a thermographic camera (e.g., an infrared camera), a radar system (which may comprise, for example, a transmitter, a receiver, a processor, and one or more antennae), a stereo camera or any other imaging device 112 suitable for obtaining images of an anatomical feature of a patient. The imaging device 112 may be contained entirely within a single housing, or may comprise a transmitter / emitter and a receiver / detector that are in separate housings or are otherwise physically separated. In some embodiments, a first imaging device 112 may be used to obtain first image data (e.g., a first image) at a first time, and a second imaging device 112 may be used to obtain second image data (e.g., a second image) at a second time after the first time. In some embodiments (and as will be described below) the first imaging device can be an imaging device that is used for navigation. In other words, the first imaging device may be a navigation imaging device used with the navigation system 118. The first imaging device may be, for example, any of the example imaging devices described above (an ultrasound scanner, an O-arm, a C-arm, a G-arm, or any other device utilizing X-ray-based imaging, a magnetic resonance imaging scanner, an OCT scanner, an endoscope, a microscope, an optical camera, a thermographic camera, a radar system, a stereo camera, etc.). The second imaging device may be an imaging device used for registration. In some embodiments, the second imaging device is the stereo camera, as will be discussed in detail in Fig. 2 below.

[0069] In some embodiments, the imaging device 112 may comprise more than one imaging device 112. For example, a first imaging device may provide first image data and / or a first image, and a second imaging device may provide second image data and / or a second image. In still other embodiments, the same imaging device may be used to provide both the first image data and the second image data, and / or any other image data described herein. The imaging device 112 may be operable to generate a stream of image data. For example, the imaging device 112 may be configured to operate with an open shutter, or with a shutter that continuously alternates between open and shut so as to capture successive images. For purposes of the present disclosure, unless specified otherwise, image data may be considered to be continuous and / or provided as an image data stream if the image data represents two or more frames per second.

[0070] The projector 136 may comprise a vertical-cavity surface-emitting laser (VCSEL) or a simple laser with a diffraction grating to project a pattern. In other embodiments, the projector136 may comprise any projector 136 configured to project any pattern such as, for example, a digital light processing (DLP) projector, a light emitting diode (LED) projector, an LCD projector, or a liquid crystal on silicon (LCDS) projector). The projector 136 may be supported manually by, for example, a user, or may be statically supported by, for example, a stand. In other embodiments, the projector 136 may be supported and positioned by, for example, the robot 114 (and more specifically, by a robotic arm 116 of the robot 114).

[0071] The pattern may be projected onto, for example, a patient, an object, or a combination thereof. The projected pattern may aid in identifying at least a portion of a patient onto which the pattern is projected onto (wherein the patient may be identified in the image data via, for example, by the processor 104 using the image processing 120 described above). For example, the pattern may be useful in identifying smooth portions on a patient’s face that may otherwise be difficult to identify. The pattern may be any pattern such as, for example, a plurality of dots, a plurality of lines, a noise pattern, a plurality of any shape, or a plurality of any combination of shapes.

[0072] The mask 138 may be configured to block at least a portion of the projected pattern from the projector 136. As will be described in more detail in Figs. 3-5, a reference marker such as the reference marker 140 may be positioned on a portion of the patient. When the projected pattern is projected onto the portion of the patient with the reference marker 140, the projected pattern may distort the reference marker 140. Thus, it is desirable to block or mask a portion of the projected pattern that covers and distorts the reference marker 140.

[0073] The mask 138 may be positioned within a trajectory of the pattern projected by the projector 136 and may be positioned, for example, in front of the projector 136. In other instances, the projector 136 and the mask 138 are integrated. For example, the projector 136 and the mask 138 may comprise an LCD projector on which the LCD projector includes an LCD panel. In other embodiments, the projector 136 and the mask 138 (e.g., LCD panel) are separate components. In embodiments where the mask 138 is an LCD panel, the LCD panel includes pixels that can be individually controlled by, for example, the processor 104 of the computing device 102, a processor of the navigation system 118, or any other processor. Thus, the pixels within the determined boundary can be controlled to block the pattern within the boundary by, for example, blacking out each pixel within the boundary. In still other instances, the mask 138 may comprise a manual, physical mask (e.g., cardboard, tape, cardstock, plywood, etc.) that can be shaped to a desired boundary shape and positioned on the projector to physically block a portion of the projected pattern.

[0074] The robot 114 may be any surgical robot or surgical robotic system. The robot 114 may be or comprise, for example, the Mazor X™ Stealth Edition robotic guidance system. The robot 114 may be configured to position the imaging device 112 at one or more precise position(s) and orientation(s), and / or to return the imaging device 112 to the same position(s) and orientation(s) at a later point in time. The robot 114 may additionally or alternatively be configured to manipulate a surgical tool (whether based on guidance from the navigation system 118 or not) to accomplish or to assist with a surgical task. In some embodiments, the robot 114 may be configured to hold and / or manipulate an anatomical element during or in connection with a surgical procedure. The robot 114 may comprise one or more robotic arms 116. In some embodiments, the robotic arm 116 may comprise a first robotic arm and a second robotic arm, though the robot 114 may comprise more than two robotic arms. In some embodiments, one or more of the robotic arms 116 may be used to hold and / or maneuver the imaging device 112. In embodiments where the imaging device 112 comprises two or more physically separate components (e.g., a transmitter and receiver), one robotic arm 116 may hold one such component, and another robotic arm 116 may hold another such component. Each robotic arm 116 may be positionable independently of the other robotic arm. The robotic arms 116 may be controlled in a single, shared coordinate space, or in separate coordinate spaces.

[0075] The robot 114, together with the robotic arm 116, may have, for example, one, two, three, four, five, six, seven, or more degrees of freedom. Further, the robotic arm 116 may be positioned or positionable in any pose, plane, and / or focal point. The pose includes a position and an orientation. As a result, an imaging device 112, surgical tool, or other object held by the robot 114 (or, more specifically, by the robotic arm 116) may be precisely positionable in one or more needed and specific positions and orientations.

[0076] The robotic arm(s) 116 may comprise one or more sensors that enable the processor 104 (or a processor of the robot 114) to determine a precise pose in space of the robotic arm (as well as any object or element held by or secured to the robotic arm).

[0077] In some embodiments, one or more reference markers 140 (e.g., navigation markers) may be placed on the robot 114 (including, e.g., on the robotic arm 116), the imaging device 112, a patient, or any other object in the surgical space. The reference markers 140 may be tracked by the navigation system 118, and the results of the tracking may be used by the robot 114 and / or by an operator of the system 100 or any component thereof. In some embodiments, the navigation system 118 can be used to track other components of the system (e.g., imaging device 112) and the system can operate without the use of the robot 114 (e.g., with the surgeon manuallymanipulating the imaging device 112 and / or one or more surgical tools, based on information and / or instructions generated by the navigation system 118, for example). The reference markers 140 may comprise one or more active markers, one or more passive markers, or a combination of active and passive markers. The reference markers 140 may be, for example, light emitting diodes, infrared light emitting diodes, reflective markers, or the like.

[0078] The navigation system 118 may provide navigation for a surgeon and / or a surgical robot during an operation. The navigation system 118 may be any now-known or future-developed navigation system, including, for example, the Medtronic StealthStation™ S8 surgical navigation system or any successor thereof. The navigation system 118 may include one or more cameras or other sensor(s) for tracking one or more reference markers, navigated trackers, or other objects within the operating room or other room in which some or all of the system 100 is located. The one or more cameras may be optical cameras, infrared cameras, or other cameras. In some embodiments, the navigation system 118 may comprise one or more electromagnetic sensors. In various embodiments, the navigation system 118 may be used to track a position and orientation (e.g., a pose) of the imaging device 112, the patient (via the reference marker 140), the robot 114 and / or robotic arm 116, and / or one or more surgical tools (or, more particularly, to track a pose of a navigated tracker attached, directly or indirectly, in fixed relation to the one or more of the foregoing). The navigation system 118 may include a display for displaying one or more images from an external source (e.g., the computing device 102, imaging device 112, the projector 136, or other source) or for displaying an image and / or video stream from the one or more cameras or other sensors of the navigation system 118. In some embodiments, the system 100 can operate without the use of the navigation system 118. The navigation system 118 may be configured to provide guidance to a surgeon or other user of the system 100 or a component thereof, to the robot 114, or to any other element of the system 100 regarding, for example, a pose of one or more anatomical elements, whether or not a tool is in the proper trajectory, and / or how to move a tool into the proper trajectory to carry out a surgical task according to a preoperative or other surgical plan.

[0079] The database 130 may store information that correlates one coordinate system to another (e.g., one or more robotic coordinate systems to a patient coordinate system and / or to a navigation coordinate system). The database 130 may additionally or alternatively store, for example, one or more surgical plans (including, for example, pose information about a target and / or image information about a patient’s anatomy at and / or proximate the surgical site, for use by the robot 114, the navigation system 118, and / or a user of the computing device 102 or of thesystem 100); one or more images useful in connection with a surgery to be completed by or with the assistance of one or more other components of the system 100; and / or any other useful information. The database 130 may be configured to provide any such information to the computing device 102 or to any other device of the system 100 or external to the system 100, whether directly or via the cloud 134. In some embodiments, the database 130 may be or comprise part of a hospital image storage system, such as a picture archiving and communication system (PACS), a health information system (HIS), and / or another system for collecting, storing, managing, and / or transmitting electronic medical records including image data.

[0080] The cloud 134 may be or represent the Internet or any other wide area network. The computing device 102 may be connected to the cloud 134 via the communication interface 108, using a wired connection, a wireless connection, or both. In some embodiments, the computing device 102 may communicate with the database 130 and / or an external device (e.g., a computing device) via the cloud 134.

[0081] The system 100 or similar systems may be used, for example, to carry out one or more aspects of any of the method 500 described herein. The system 100 or similar systems may also be used for other purposes.

[0082] Fig. 2 illustrates additional aspects of the system 100 in accordance with embodiments of the present disclosure. Fig. 2 depicts the imaging device 112 that operates as a stereo camera with a first image sensor 204 and a second image sensor 208 that can be used to capture stereo images of a patient 212.

[0083] The first image sensor 204 and the second image sensor 208 are each capable of generating information or image data that can be processed to produce a pair of 2D images of the patient 212. The first image sensor 204 and the second image sensor 208 may be separated by a predetermined or otherwise known distance, such that the field of view (FOV) of the first image sensor 204 is different than the FOV of the second image sensor 208. For example, the first image sensor 204 may have a first FOV 216 while the second image sensor 208 may have a second FOV 220 different from the first FOV 216. As a result, data generated by the first image sensor 204 is different from the data generated by the second image sensor 208 when the imaging device 112 images the patient 212, such that each image of the pair of 2D images depicts features of the patient 212 from different angles, directions, and / or orientations. In other words, a first 2D image of the pair of 2D images depicts features of the patient 212 in a first orientation or pose, while a second 2D image of the pair of 2D images depicts the features of the patient 212 from a different angle, direction, and / or orientation or pose.

[0084] As depicted in Fig. 2, the first image sensor 204 is positioned left of a centerline 214 of the patient 212 while the second image sensor 208 is positioned to the right of the centerline 214 of the patient 212. The resulting data from the first image sensor 204, when processed by image processing 120, may result in an image depicting a left-side view of the patient 212 (also referred to herein as a left eye view of the patient 212). Similarly, the resulting data from the second image sensor 208, when processed by the image processing 120, may result in an image depicting a right-side view of the patient 212 (also referred to herein as a right eye view of the patient 212). In some cases, one or both of the 2D images (e.g., the right-side view and / or the left- side view) may be rendered to a display to enable a user of the system 100 to view the 2D image(s). It should be understood that, while embodiments of the present disclosure discuss leftside and right-side views of the patient 212, additional or alternative imaging of the patient may occur, and that any portion of the patient 212 may be imaged by the stereo camera to produce a pair of 2D images depicting the portion of the patient 212.

[0085] The pose of the first image sensor 204 relative to the second image sensor 208 (and vice versa) may be known or determined by the system 100. In some cases, the pose information may be stored in the database 130. Additionally or alternatively, the pose information may be determined by the navigation system 118 based on the pose of tracked fiducials in a known pose relative to the first image sensor 204 and / or the second image sensor 208.

[0086] Fig. 3 illustrates additional aspects of the system 100 in accordance with embodiments of the present disclosure. Fig. 3 depicts the imaging device 112 having the first image sensor 204 and the second image sensor 208 that operates as a stereo camera as described above in Fig. 2; the projector 136 configured to project a pattern 302; and the mask 138 positioned within a trajectory of the pattern 302 and configured to mask or block at least a portion of the pattern 302. As shown, a portion of the mask 304 defined by a boundary 304 can block the portion of the pattern 302. In instances where the mask 304 is an LCD screen, the pixels within the boundary 304 can be controlled to turn black or dark so as to block the pattern 302. The boundary 304 is determined by a shape of the reference marker 140, as will be described below. As will also be described below, by blocking a portion of the pattern 302 where the reference marker 140 is positioned, the patient 212 can be identified in the image data with the pattern 302 projected onto the patient 212 (thus, increasing an accuracy of identifying and obtaining the pose of the patient 212) and the reference marker 140 can be identified in the image data without the pattern 302 obscuring and distorting the reference marker 140.

[0087] Figs. 4A-4C illustrate an example reference marker that may be the same as or similar to the reference marker 140 positioned on a patient such as the patient 212 with the projector 136 turned off, with the projector 136 turned on, and with the projector 136 turned on and the mask 138 enabled within the boundary 304, respectively.

[0088] As shown in Fig. 4A and previously described, a reference marker such as the reference marker 140 is positioned on the patient 212 for patient tracking by, for example, the navigation system 118. In the illustrated example, the reference marker 140 includes a combination of an electromagnetic (EM) tracker and an optical tracker. As shown, the optical tracker is in the form of a cube with a checkered pattern that is easily identifiable within the image data captured or obtained by the imaging device 112. It will be appreciated that in other embodiments, the reference marker 140 may include any type of marker or tracker, any pattern, and any combination of markers or trackers or patterns. For example, the optical tracker may be an acruco marker, a QR code, or the like.

[0089] In addition to identifying and tracking the reference marker 140 for registration, the patient 212 is also identified in the image data for registration. Because portions of the patient 212 (for example, the forehead) may be difficult to identify in image data, a pattern such as the pattern 302 can be projected onto the patient 212 by the projector 136. Such pattern 302 gives texture to the patient 212, thereby increasing an accuracy of identifying the patient 212 in image data. However, as shown in Fig. 4B, the pattern 302 when projected onto the patient 212 and the reference marker 140 may obscure the reference marker 140 such that the reference marker 140 is difficult to identify in image data. Thus, it is desirable to project the pattern 302 onto the patient 212, but not the reference marker 140. As previously described, to achieve projection of the pattern 302 onto the patient 212 but not the reference marker 140, the mask 138 is configured to block a portion of the pattern 302 such that that pattern 302 is not projected onto the reference marker 140.

[0090] To determine the boundary 304 to block using the mask 138, the reference marker 140 is identified in image data obtained from, for example, the imaging device 112 (e.g., the stereo camera) when the projector 136 is turned off. An outline or an edge of the reference marker 140 can be identified in the image data and the corresponding boundary 304 can be determined based on the outline or edge of the reference marker 140. In other embodiments, dimension(s) of the reference marker 140 is known and provided to, for example, the system 100 or the navigation system 118. A pose of the reference marker 140 can also be determined from the image data using the image processing 120 or using, for example, triangulation in the pair of imagesobtained from the imaging device 112 when the imaging device 112 is a stereo camera. An outline of the reference marker 140 can be projected onto the mask 138 based on the determined pose.. The boundary 304 can then be determined from the projected outline. Alternatively or additionally, the identified outline or known dimensions of the reference marker 140 can be used with the determined pose to determined the boundary 304. In embodiments where the mask 138 comprises the LCD screen, pixels within the boundary 304 can be blacked out or otherwise controlled to block the pattern 302 within the boundary 304. When the mask 138 is enabled with the boundary 304 and the projector 136 is turned on, the pattern 302 is projected onto the patient 212, but not the reference marker 140, as shown in Fig. 4C.

[0091] Fig. 5 depicts a method 500 that may be used, for example, for touchless registration of one or more coordinate systems using a projector such as the project 136 and a mask such as the mask 138.

[0092] The method 500 (and / or one or more steps thereof) may be carried out or otherwise performed, for example, by at least one processor. The at least one processor may be the same as or similar to the processor(s) 104 of the computing device 102 described above. The at least one processor may be part of a robot (such as a robot 114) or part of a navigation system (such as a navigation system 118). A processor other than any processor described herein may also be used to execute the method 500. The at least one processor may perform the method 500 by executing elements stored in a memory such as the memory 106. The elements stored in memory and executed by the processor may cause the processor to execute one or more steps of a function as shown in method 500. One or more portions of a method 500 may be performed by the processor executing any of the contents of memory, such as an image processing 120, a segmentation 122, a registration 124, and / or a transformation 128.

[0093] The method 500 comprises receiving one or more first images (step 504). The first image(s) may be received from an imaging device such as the imaging device 112. In embodiments where the imaging device is a stereo camera, the one or more first images may comprise a pair of first images. In other embodiments, the one or more first images may be received via a user interface such as the user interface 110 and / or a communication interface such as the communication interface 108 of a computing device such as the computing device 102, and may be stored in a memory such as the memory 106 of the computing device. The image(s) may also be received from an external database or image repository (e.g., a hospital image storage system, such as a picture archiving and communication system (PACS), a health information system (HIS), and / or another system for collecting, storing, managing, and / ortransmitting electronic medical records including image data), and / or via the Internet or another network. The image (s)may also be generated by and / or uploaded to any other component of a system such as the system 100. In some embodiments, the image may be indirectly received via any other component of the system or a node of a network to which the system is connected.

[0094] The image may be a 2D image or a 3D image or a set of 2D and / or 3D images. For example, when the imaging device is a stereo camera, the image(s) are a pair of 2D images taken from a first image sensor such as the first image sensor 204 taken at a first pose and a second image sensor such as the second image sensor 208 taken at a second pose different from the first pose. The image may depict a patient such as the patient 212 and a reference marker such as the reference marker 140 positioned on the patient. The image may be obtained with a projector such as the projector 136 turned off.

[0095] In some embodiments, the image may be captured preoperatively (e.g., before surgery) and may be stored in a system (e.g., a system 100) and / or one or more components thereof (e.g., a database 130). The stored image may then be received (e.g., by a processor 104), as described above, preoperatively (e.g., before the surgery) and / or intraoperatively (e.g., during surgery).

[0096] The method 500 also comprises identifying at least one object in each first image (step 508). The object may be the reference marker. As previously described, the reference marker may include a combination of an EM tracker and an optical tracker, though it will be appreciated that the reference marker may include any type of reference marker or combination thereof. The optical tracker may include a pattern such as a checkered pattern that is easily identifiable in the first image(s).

[0097] Each image may be processed by a processor such as the processor 104 using an image processing such as the image processing 120 to identify the patient and / or the object(s) (e.g., reference marker) in each of the first images. In some embodiments, feature recognition may be used to identify a feature of the reference marker. For example, the checkered pattern (or any pattern depicted on the reference marker) be identified in the first images. In other embodiments the image processing may use segmentation such as the segmentation 122 to identify the object.

[0098] The method 500 also comprises determining a pose of the object (step 510). The pose of the object may also be determined by the processor using the image processing. More specifically, in embodiments where the imaging device is the stereo camera, the pair of first images obtained from the stereo camera can be used to triangulate the pose of the reference marker.

[0099] The method 500 also comprises determining a boundary on a mask based on the object (step 512). As previously described, to determine a boundary such as the boundary 304 to block a portion of a pattern such as the pattern 302 projected by the projector using a mask such as the mask 138, the reference marker is identified in the first image data in the step 508 described above when the projector is turned off. An outline or an edge of the reference marker can be identified in the image data (also in, for example, the step 508) and the corresponding boundary can be determined based on the outline or edge of the reference marker. In other embodiments, dimension(s) of the reference marker is known and provided to, for example, the system or the navigation system. A pose of the reference marker can also be determined from the image data as described in the step 510. An outline of the reference marker can be projected onto the mask based on the determined pose. The boundary can then be determined from the projected outline and in embodiments. Alternatively or additionally, the boundary can be determined from the pose of the reference marker and the known dimensions of the reference marker. In embodiments where the mask comprises an LCD screen or an LCD projector, pixels within the boundary can be blacked out or otherwise controlled to block the pattern within the boundary. Thus, when the mask is enabled with the boundary and the projector is turned on, the pattern is projected onto the patient, but not the reference marker.

[0100] The method 500 also comprises causing a portion of the mask within the boundary to block a corresponding portion of the projector (step 516). The portion of the mask within the boundary may be configured to block the corresponding portion of the pattern projected by the projector. In embodiments where the mask is an LCD screen or panel, the pixels within the boundary may be blacked out or otherwise controlled to block the pattern within the boundary. In other embodiments, the mask may include a physical mask that can be shaped to the shape of the boundary and positioned to physically block a portion of the pattern within the boundary.

[0101] The method 500 also comprises turning the projector on (step 518). The projector may be automatically turned on by, for example, the system or the navigation system. In other embodiments, the projector may be turned on based on user input.

[0102] The method 500 also comprises receiving one or more second images (step 520). The step 520 is the same as or similar to the step 508 described above with respect to receiving image(s). The one or more second images are obtained when the projector is turned on and projects the pattern and the mask is enabled to block a portion of the pattern within the boundary. Thus, the image data depicts the patient with the pattern projected onto the patient and the object (e.g., the reference marker) without the pattern projected onto the object.

[0103] The method 500 also comprises identifying the patient and the object in each second image (step 522). The step 522 may be the same as or similar to the step 510 except that the patient is also identified in each second image (along with the object (e.g., the reference marker)).

[0104] The method 500 also comprises registering a first coordinate system (step 524). The first coordinate system may be, for example, a patient coordinate system of the patient identified in the second image(s) in the step 522. The patient coordinate system may be registered by the processor using a registration such as the registration 124 to correlate, map, transform the patient coordinate system to a third coordinate system that may be, for example, an imaging device coordinate system. The registration may enable coordinates defining a particular location with respect to one coordinate space (e.g., the patient coordinate space) to be converted into coordinates defining the particular location with respect to another coordinate space (e.g., the imaging device coordinate space).

[0105] The method 500 also comprises registering a second coordinate system (step 528). The second coordinate system may be, for example, a reference marker coordinate system of the reference marker identified in the second image(s) in the step 522. The reference marker coordinate system may be registered by the processor using the registration 124 to correlate, map, or transform the reference marker coordinate system to the third coordinate system (e.g., the imaging device coordinate system). The registration may enable coordinates defining a particular location with respect to one coordinate space (e.g., the reference marker coordinate space) to be converted into coordinates defining the particular location with respect to another coordinate space (e.g., the imaging device coordinate space).

[0106] The method 500 also comprises determining a transformation to correlate the first coordinate system with the second coordinate system (step 532). The first coordinate system (e.g., the patient coordinate system) may be correlated with the second coordinate system (e.g., the reference marker coordinate system) based on their common registration with the third coordinate system (e.g., the imaging device coordinate system). The first coordinate system can be correlated with the second coordinate system by the processor using a transformation such as the transformation 128 that enables the processor to transform one coordinate system into another coordinate system. In other words, the transformation enables the processor to transform the first coordinate system (e.g., the patient coordinate system) into the second coordinate system (e.g., the reference frame coordinate system) based on the registration of the first coordinate system and the third coordinate system and the registration of the second coordinate system andthe third coordinate system. Thus, the first or patient coordinate system can be correlated to the second or reference frame coordinate system.

[0107] The present disclosure encompasses embodiments of the method 500 that comprise more or fewer steps than those described above, and / or one or more steps that are different than the steps described above.

[0108] The embodiments described herein beneficially provide for a touchless registration process of a patient and an object such as a reference marker that can be conducted using an imaging device such as a stereo camera. The registration process is also conducted in a short amount of time (~30ms) such that the stereo camera can be handheld without reducing an accuracy of the stereo camera (and subsequent registration). Thus, the registration process is simplified and easy to perform relative to conventional registration processes.

[0109] As noted above, the present disclosure encompasses methods with fewer than all of the steps identified in Fig. 5 (and the corresponding description of the method 500), as well as methods that include additional steps beyond those identified in Fig. 5 (and the corresponding description of the method 500). The present disclosure also encompasses methods that comprise one or more steps from one method described herein, and one or more steps from another method described herein. Any correlation described herein may be or comprise a registration or any other correlation.

[0110] The foregoing is not intended to limit the disclosure to the form or forms disclosed herein. In the foregoing Detailed Description, for example, various features of the disclosure are grouped together in one or more aspects, embodiments, and / or configurations for the purpose of streamlining the disclosure. The features of the aspects, embodiments, and / or configurations of the disclosure may be combined in alternate aspects, embodiments, and / or configurations other than those discussed above. This method of disclosure is not to be interpreted as reflecting an intention that the claims require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed aspect, embodiment, and / or configuration. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the disclosure.

[0111] Moreover, though the foregoing has included description of one or more aspects, embodiments, and / or configurations and certain variations and modifications, other variations, combinations, and modifications are within the scope of the disclosure, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intendedto obtain rights which include alternative aspects, embodiments, and / or configurations to the extent permitted, including alternate, interchangeable and / or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and / or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.

[0112] Example statement of the claims:

[0113] Statement 1: A system, comprising: a processor (104); and a memory (106) coupled to the processor and storing data thereon that, when processed by the processor, enables the processor to: receive one or more first images; identify at least one object in each of the first images; determine a pose of each object; determine a boundary on a mask positioned on a projector, the boundary corresponding to an outline of the at least one object; cause a portion of the mask within the boundary to block a corresponding portion of the projector; receive one or more second images; identify the at least one image and a patient in each of the second images; register a first coordinate system to a third coordinate system; register a second coordinate system to a third coordinate system; and determine a transformation to correlate the first coordinate system with the second coordinate system based on the registration of the first coordinate system and the registration of the second coordinate system.

[0114] Statement 2: The system of Statement 1, wherein the memory stores further data for processing by the processor that, when processed, enables the processor to: turn the projector on.

[0115] Statement 3: The system of any of Statements 1-2, wherein the one or more first images are received when the projector is turned off and the one or more second images are received when the projector is turned on.

[0116] Statement 4: The system of any of Statements 1-3, wherein the first coordinate system comprises a coordinate system of the patient, the second coordinate system comprises a coordinate system of the object, and the third coordinate system comprises a coordinate system of an imaging device.

[0117] Statement 5: The system of any of Statements 1-4, further comprising:

[0118] an imaging device (112) configured to obtain the one or more first images and the one or more second images.

[0119] Statement 6: The system of any of Statements 1-5, wherein the imaging device comprises a stereo camera.

[0120] Statement 7 : The system of any of Statements 1 -6, wherein the one or more first images comprises images without a pattern and the one or more second images comprises images with a pattern and a portion of the pattern blocked by the portion of the mask within the boundary.

[0121] Statement 8: The system of any of Statements 1-7, wherein the pattern comprises a plurality of dots.

[0122] Statement 9: The system of any of Statements 1-8, wherein the imaging device is supported by at least one of a stand, a user, or a robotic arm.

[0123] Statement 10: The system of any of Statements 1-9,, wherein the mask comprises a liquid crystal display (LCD) on which each pixel can be controlled, and wherein pixels within the boundary on the LCD are blacked out.

[0124] Statement I L A system, comprising: an imaging device (112); a projector (136) configured to project a pattern (302); a mask (138) configured to block at least a portion of the projector; a processor (104); and a memory (106) coupled to the processor and storing data thereon that, when processed by the processor, enables the processor to: receive one or more first images from the imaging device; identify at least one object in each of the first images; determine a pose of each object; determine a boundary on a mask positioned on a projector, the boundary corresponding to the at least one object; cause a portion of the mask within the boundary to block a corresponding portion of the projector; receive one or more second images from the imaging device; register a first coordinate system with a third coordinate system; register a second coordinate system with the third coordinate system; and determine a transformation to correlate the first coordinate system with the second coordinate system based on the registration of the first coordinate system and the registration of the second coordinate system.

[0125] Statement 12: The system of Statement 11, wherein the memory stores further data for processing by the processor that, when processed, enables the processor to: turn the projector on.

[0126] Statement 13: The system of any of Statements 11-12, wherein the one or more first images are received when the projector is turned off and the one or more second images are received when the projector is turned on.

[0127] Statement 14: The system of any of Statements 11-13, wherein the first coordinate system comprises a coordinate system of the patient, the second coordinate system comprises a coordinate system of the object, and the third coordinate system comprises a coordinate system of an imaging device.

[0128] Statement 15: The system of any of Statements 11-14, wherein the imaging device comprises a stereo camera.

[0129] Statement 16: The system of any of Statements 11-15, wherein the one or more first images comprises images without a pattern and the one or more second images comprises images with a pattern and a portion of the pattern blocked by the portion of the mask within the boundary.

[0130] Statement 17: The system of any of Statements 11-16, wherein the pattern comprises a plurality of dots.

[0131] Statement 18: The system of any of Statements 11-17, wherein the imaging device is supported by at least one of a stand, a user, or a robotic arm.

[0132] Statement 19: The system of any of Statements 11-18, wherein the mask comprises a liquid crystal display (LCD) on which each pixel can be controlled, and wherein pixels within the boundary on the LCD are blacked out.

[0133] Statement 20: A system, comprising: a stereo camera (112); a projector (136) configured to project a pattern (302) onto a patient; an LCD (138) positioned on the projector and configured to block at least a portion of the projector; a processor (104); and a memory (106)coupled to the processor and storing data thereon that, when processed by the processor, enables the processor to: receive one or more first images from the stereo camera; identify a reference marker disposed on the patient in each of the first images; determine a pose of the reference marker; determine a boundary on the LCD corresponding to an outline of the reference marker; cause a portion of the LCD within the boundary to block a corresponding portion of the projector; receive one or more second images from the stereo camera; identify the patient and the reference marker in each of the second images; register a patient coordinate system to an imaging device coordinate system; register a reference frame coordinate system to the imaging device coordinate system; and determine a transformation to correlate the patient coordinate system with the reference frame coordinate system based on the registration of the patient coordinate system and the registration of the reference frame coordinate system.

Claims

CLAIMSWhat is claimed is:

1. A system, comprising: a processor (104); and a memory (106) coupled to the processor and storing data thereon that, when processed by the processor, enables the processor to: receive one or more first images; identify at least one object in each of the first images; determine a pose of each object; determine a boundary on a mask positioned on a projector, the boundary corresponding to an outline of the at least one object; cause a portion of the mask within the boundary to block a corresponding portion of the projector; receive one or more second images; identify the at least one image and a patient in each of the second images; register a first coordinate system to a third coordinate system; register a second coordinate system to a third coordinate system; and determine a transformation to correlate the first coordinate system with the second coordinate system based on the registration of the first coordinate system and the registration of the second coordinate system.

2. The system of claim 1 , wherein the memory stores further data for processing by the processor that, when processed, enables the processor to: turn the projector on.

3. The system of claim 2, wherein the one or more first images are received when the projector is turned off and the one or more second images are received when the projector is turned on.

4. The system of any of preceding claims 1-3, wherein the first coordinate system comprises a coordinate system of the patient, the second coordinate system comprises a coordinate system of the object, and the third coordinate system comprises a coordinate system of an imaging device.

5. The system of any of preceding claims 1-4, further comprising: an imaging device (112) configured to obtain the one or more first images and the one or more second images.

6. The system of claim 5, wherein the imaging device comprises a stereo camera.

7. The system of any of preceding claims 1-6, wherein the one or more first images comprises images without a pattern and the one or more second images comprises images with a pattern and a portion of the pattern blocked by the portion of the mask within the boundary.

8. The system of claim 7, wherein the pattern comprises a plurality of dots.

9. The system of claim 5, wherein the imaging device is supported by at least one of a stand, a user, or a robotic arm.

10. The system of any of preceding claims 1-9, wherein the mask comprises a liquid crystal display (LCD) on which each pixel can be controlled, and wherein pixels within the boundary on the LCD are blacked out.

11. A system, comprising: an imaging device (112); a projector (136) configured to project a pattern (302); a mask (138) configured to block at least a portion of the projector; a processor (104); and a memory (106) coupled to the processor and storing data thereon that, when processed by the processor, enables the processor to: receive one or more first images from the imaging device; identify at least one object in each of the first images; determine a pose of each object; determine a boundary on a mask positioned on a projector, the boundary corresponding to the at least one object; cause a portion of the mask within the boundary to block a corresponding portion of the projector;receive one or more second images from the imaging device; register a first coordinate system with a third coordinate system; register a second coordinate system with the third coordinate system; and determine a transformation to correlate the first coordinate system with the second coordinate system based on the registration of the first coordinate system and the registration of the second coordinate system.

12. The system of claim 11, wherein the memory stores further data for processing by the processor that, when processed, enables the processor to: turn the projector on.

13. The system of claim 12, wherein the one or more first images are received when the projector is turned off and the one or more second images are received when the projector is turned on.

14. The system of any of preceding claims 11-13, wherein the first coordinate system comprises a coordinate system of the patient, the second coordinate system comprises a coordinate system of the object, and the third coordinate system comprises a coordinate system of an imaging device.

15. A system, comprising: a stereo camera (112); a projector (136) configured to project a pattern (302) onto a patient; an LCD (138) positioned on the projector and configured to block at least a portion of the projector; a processor (104); and a memory (106)coupled to the processor and storing data thereon that, when processed by the processor, enables the processor to: receive one or more first images from the stereo camera; identify a reference marker disposed on the patient in each of the first images; determine a pose of the reference marker; determine a boundary on the LCD corresponding to an outline of the reference marker; cause a portion of the LCD within the boundary to block a corresponding portion of the projector;receive one or more second images from the stereo camera; identify the patient and the reference marker in each of the second images register a patient coordinate system to an imaging device coordinate system; register a reference frame coordinate system to the imaging device coordinate system; and determine a transformation to correlate the patient coordinate system with the reference frame coordinate system based on the registration of the patient coordinate system and the registration of the reference frame coordinate system.

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