CA2958013C - Patient reference device - Google Patents
Patient reference device Download PDFInfo
- Publication number
- CA2958013C CA2958013C CA2958013A CA2958013A CA2958013C CA 2958013 C CA2958013 C CA 2958013C CA 2958013 A CA2958013 A CA 2958013A CA 2958013 A CA2958013 A CA 2958013A CA 2958013 C CA2958013 C CA 2958013C
- Authority
- CA
- Canada
- Prior art keywords
- attachment base
- patient
- reference device
- patient reference
- alarm
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000033001 locomotion Effects 0.000 claims abstract description 32
- 230000003287 optical effect Effects 0.000 claims abstract description 25
- 230000008859 change Effects 0.000 claims abstract description 18
- 238000005259 measurement Methods 0.000 claims abstract description 17
- 230000004044 response Effects 0.000 claims abstract description 6
- 230000007246 mechanism Effects 0.000 claims description 41
- 238000001356 surgical procedure Methods 0.000 claims description 28
- 238000004891 communication Methods 0.000 claims description 17
- 238000010168 coupling process Methods 0.000 claims description 8
- 238000005859 coupling reaction Methods 0.000 claims description 8
- 230000000007 visual effect Effects 0.000 claims description 4
- 238000000034 method Methods 0.000 abstract description 35
- 210000003484 anatomy Anatomy 0.000 abstract description 31
- 238000003384 imaging method Methods 0.000 description 13
- 230000008569 process Effects 0.000 description 10
- 238000002595 magnetic resonance imaging Methods 0.000 description 9
- 239000003550 marker Substances 0.000 description 9
- 238000012544 monitoring process Methods 0.000 description 8
- 230000008878 coupling Effects 0.000 description 5
- 201000010099 disease Diseases 0.000 description 5
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 5
- 239000000853 adhesive Substances 0.000 description 4
- 230000001070 adhesive effect Effects 0.000 description 4
- 238000013459 approach Methods 0.000 description 4
- 210000000988 bone and bone Anatomy 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 238000001959 radiotherapy Methods 0.000 description 4
- 210000001519 tissue Anatomy 0.000 description 4
- 239000002872 contrast media Substances 0.000 description 3
- 238000003745 diagnosis Methods 0.000 description 3
- 239000003814 drug Substances 0.000 description 3
- 206010028980 Neoplasm Diseases 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 2
- 230000003044 adaptive effect Effects 0.000 description 2
- 210000004556 brain Anatomy 0.000 description 2
- QXJJQWWVWRCVQT-UHFFFAOYSA-K calcium;sodium;phosphate Chemical compound [Na+].[Ca+2].[O-]P([O-])([O-])=O QXJJQWWVWRCVQT-UHFFFAOYSA-K 0.000 description 2
- 238000009104 chemotherapy regimen Methods 0.000 description 2
- 238000005286 illumination Methods 0.000 description 2
- 238000001990 intravenous administration Methods 0.000 description 2
- 230000000399 orthopedic effect Effects 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 210000000130 stem cell Anatomy 0.000 description 2
- 238000012800 visualization Methods 0.000 description 2
- 206010002091 Anaesthesia Diseases 0.000 description 1
- 208000003174 Brain Neoplasms Diseases 0.000 description 1
- 206010008111 Cerebral haemorrhage Diseases 0.000 description 1
- 241001269524 Dura Species 0.000 description 1
- 229910052688 Gadolinium Inorganic materials 0.000 description 1
- 208000006011 Stroke Diseases 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 230000037005 anaesthesia Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000008499 blood brain barrier function Effects 0.000 description 1
- 210000004204 blood vessel Anatomy 0.000 description 1
- 210000001218 blood-brain barrier Anatomy 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000002591 computed tomography Methods 0.000 description 1
- 238000007428 craniotomy Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- UIWYJDYFSGRHKR-UHFFFAOYSA-N gadolinium atom Chemical compound [Gd] UIWYJDYFSGRHKR-UHFFFAOYSA-N 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 208000020658 intracerebral hemorrhage Diseases 0.000 description 1
- 230000005865 ionizing radiation Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000004770 neurodegeneration Effects 0.000 description 1
- 208000015122 neurodegenerative disease Diseases 0.000 description 1
- 238000012634 optical imaging Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 238000002600 positron emission tomography Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000011664 signaling Effects 0.000 description 1
- 210000003625 skull Anatomy 0.000 description 1
- 210000004872 soft tissue Anatomy 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000003325 tomography Methods 0.000 description 1
- 238000002604 ultrasonography Methods 0.000 description 1
- 238000012285 ultrasound imaging Methods 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
- A61B34/20—Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
- A61B34/20—Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
- A61B2034/2046—Tracking techniques
- A61B2034/2055—Optical tracking systems
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
- A61B34/20—Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
- A61B2034/2046—Tracking techniques
- A61B2034/2065—Tracking using image or pattern recognition
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B90/00—Instruments, implements or accessories specially adapted for surgery or diagnosis and not covered by any of the groups A61B1/00 - A61B50/00, e.g. for luxation treatment or for protecting wound edges
- A61B90/39—Markers, e.g. radio-opaque or breast lesions markers
- A61B2090/3983—Reference marker arrangements for use with image guided surgery
Landscapes
- Health & Medical Sciences (AREA)
- Surgery (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Biomedical Technology (AREA)
- Robotics (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Heart & Thoracic Surgery (AREA)
- Medical Informatics (AREA)
- Molecular Biology (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
Methods and devices to track patient anatomy during a surgical operation. A patient reference device is attached to an anatomical feature of a patient and it includes an attachment base and an optically-trackable array detectable by an optical navigation system and having a longitudinally-extending arm to space apart the fixed geometric pattern from the anatomical feature. The arm includes a connector to be detachably secured to the attachment base. An inertial measurement unit within the attachment base enables determining, based on comparing a threshold level to a motion signal, that the attachment base has changed position, wherein the motion signal represents the change in position and its magnitude. Based on determining that the attachment base has changed position an alarm signal is generated an and an output device in the attachment base outputs an alarm in response to the alarm signal
Description
PATIENT REFERENCE DEVICE
FIELD
[0001] The present application generally relates to optical navigation systems used in surgical operations and, in particular, to a patient reference device to be attached to the patient and tracked by an optical navigation system.
BACKGROUND
FIELD
[0001] The present application generally relates to optical navigation systems used in surgical operations and, in particular, to a patient reference device to be attached to the patient and tracked by an optical navigation system.
BACKGROUND
[0002] In the field of medicine, imaging and image guidance are a significant component of clinical care. From diagnosis and monitoring of disease, to planning of the surgical approach, to guidance during procedures and follow-up after the procedure is complete, imaging and image guidance provides effective and multifaceted treatment approaches, for a variety of procedures, including surgery and radiation therapy. Targeted stem cell delivery, adaptive chemotherapy regimens, and radiation therapy are only a few examples of procedures utilizing imaging guidance in the medical field.
Optical tracking systems, used during a medical procedure, track the position of a part of the instrument that is within line-of-site of the optical tracking camera. These optical tracking systems also require a reference to the patient to know where the instrument is relative to the target (e.g., a tumour) of the medical procedure, or to accurately assess positioning of relative parts of patient anatomy or orthopedic medical devices.
Optical tracking systems, used during a medical procedure, track the position of a part of the instrument that is within line-of-site of the optical tracking camera. These optical tracking systems also require a reference to the patient to know where the instrument is relative to the target (e.g., a tumour) of the medical procedure, or to accurately assess positioning of relative parts of patient anatomy or orthopedic medical devices.
[0003] In some surgeries, a patient reference device that includes an optically-trackable component that the navigation system is capable of tracking is fixedly attached to the patient. Provided a proper registration process in undertaken, the navigation system is then able to determine the position of patient anatomy in its coordinate space, so that it is able to track (and display) patient anatomy relative to tracked instruments and devices by also tracking the patient reference device.
[0004] In some cases, the patient reference device maybe inadvertently bumped during the surgery which can move the patient reference device, cause it to break, or cause the bone to which it is attached to fracture. If the device moves relative to the patient, then the registration is lost and the surgery must either proceed without navigation or it must be stopped to reattach the device and re-perform the registration process. At worst the movement of the patient reference device is not noticed and the surgery proceeds using an inaccurate registration. Accordingly, it would be advantageous to reduce the likelihood of loss of registration and to accurately determine whether re-registration is necessary.
BRIEF SUMMARY
BRIEF SUMMARY
[0005] The present application describes a patient reference device for tracking anatomical location of a patient by an optical navigation system during a surgical procedure.
The patient reference device includes an attachment base having an attachment mechanism to secure the attachment base to an anatomical feature of the patient; a optically-trackable array including a plurality of fiducials in a fixed geometric pattern to be detected by the optical navigation system and having a longitudinally-extending arm to space apart the fixed geometric pattern from the anatomical feature, the arm including a connector to be detachably secured to the attachment base; an inertial measurement unit in the attachment base to detect a change in position of the attachment base and to output a motion signal representing the change in position and its magnitude; a logic circuit to receive the motion signal and to compare it to a threshold level and, if the motion signal exceeds the threshold level, to generate an alarm signal; and an output device to output an alarm in response to the alarm signal.
The patient reference device includes an attachment base having an attachment mechanism to secure the attachment base to an anatomical feature of the patient; a optically-trackable array including a plurality of fiducials in a fixed geometric pattern to be detected by the optical navigation system and having a longitudinally-extending arm to space apart the fixed geometric pattern from the anatomical feature, the arm including a connector to be detachably secured to the attachment base; an inertial measurement unit in the attachment base to detect a change in position of the attachment base and to output a motion signal representing the change in position and its magnitude; a logic circuit to receive the motion signal and to compare it to a threshold level and, if the motion signal exceeds the threshold level, to generate an alarm signal; and an output device to output an alarm in response to the alarm signal.
[0006] In another aspect, the present application describes a method of tracking patient anatomy during a surgical operation using an optical navigation system and a patient reference device, the patient reference device being attached to an anatomical feature of the patient, the patient reference device including an attachment base having an attachment mechanism to secure the attachment base to the anatomical feature and a optically-trackable array including a plurality of fiducials in a fixed geometric pattern to be detected by the optical navigation system and having a longitudinally-extending arm to space apart the fixed geometric pattern from the anatomical feature, the arm including a connector to be detachably secured to the attachment base. The method includes determining, based on comparing a threshold level to a motion signal from an inertial measurement unit within the attachment base, that the attachment base has changed position, wherein the motion signal represents the SMI 408 Rowand LLP 313-change in position and its magnitude; based on determining that the attachment base has changed position, generating an alarm signal; and outputting, via an output device in the attachment base, an alarm in response to the alarm signal.
[0007] In yet a further aspect, the present application describes non-transitory computer-readable media storing computer-executable program instructions which, when executed, configured a processor and/or logic circuitry to perform the described methods.
[0008] Other aspects and features of the present application will be understood by those of ordinary skill in the art from a review of the following description of examples in conjunction with the accompanying figures.
[0009] In the present application, the term "and/or" is intended to cover all possible combination and sub-combinations of the listed elements, including any one of the listed elements alone, any sub-combination, or all of the elements, and without necessarily excluding additional elements.
[0010] In the present application, the phrase "at least one of ...or..." is intended to cover any one or more of the listed elements, including any one of the listed elements alone, any sub-combination, or all of the elements, without necessarily excluding any additional elements, and without necessarily requiring all of the elements.
BRIEF DESCRIPTION OF THE DRAWINGS
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Reference will now be made, by way of example, to the accompanying drawings which show example embodiments of the present application, and in which:
[0012] FIG. I diagrammatically illustrates, in perspective view, a navigation system;
[0013] FIG. 2 shows, in block diagram form, an example of the navigation system;
[0014] FIG. 3 shows a perspective view of one example embodiment of a multi-part patient reference device;
[0015] FIG. 4 shows, diagrammatically, one example embodiment of the attachment base;
SMI 408 Rowand LLP 313-
SMI 408 Rowand LLP 313-
[0016] FIG. 5 shows another example embodiment of an attachment base;
[0017] FIG. 6 shows an example of a battery housing; and
[0018] FIG. 7 shows, in flowchart form, one example method for tracking patient anatomy during a surgical operation.
[0019] Similar reference numerals may have been used in different figures to denote similar components.
DESCRIPTION OF EXAMPLE EMBODIMENTS
DESCRIPTION OF EXAMPLE EMBODIMENTS
[0020] Advanced imaging modalities such as Magnetic Resonance Imaging ("MRI") have led to improved rates and accuracy of detection, diagnosis and staging in several fields of medicine including neurology, where imaging of diseases such as brain cancer, stroke, Intra-Cerebral Hemorrhage ("ICH"), and neurodegenerative diseases, such as Parkinson's and Alzheimer's, are performed. As an imaging modality, MRI enables three-dimensional visualization of tissue with high contrast in soft tissue without the use of ionizing radiation.
This modality is often used in conjunction with other modalities such as Ultrasound ("US"), Positron Emission Tomography ("PET") and Computed X-ray Tomography ("CT"), by examining the same tissue using the different physical principles available with each modality. CT is often used to visualize bony structures and blood vessels when used in conjunction with an intra-venous agent such as an iodinated contrast agent.
MRI may also be performed using a similar contrast agent, such as an intra-venous gadolinium-based contrast agent which has pharmaco-kinetic properties that enable visualization of tumors and break-down of the blood brain barrier. These multi-modality solutions can provide varying degrees of contrast between different tissue types, tissue function, and disease states. Imaging modalities can be used in isolation, or in combination to better differentiate and diagnose disease.
This modality is often used in conjunction with other modalities such as Ultrasound ("US"), Positron Emission Tomography ("PET") and Computed X-ray Tomography ("CT"), by examining the same tissue using the different physical principles available with each modality. CT is often used to visualize bony structures and blood vessels when used in conjunction with an intra-venous agent such as an iodinated contrast agent.
MRI may also be performed using a similar contrast agent, such as an intra-venous gadolinium-based contrast agent which has pharmaco-kinetic properties that enable visualization of tumors and break-down of the blood brain barrier. These multi-modality solutions can provide varying degrees of contrast between different tissue types, tissue function, and disease states. Imaging modalities can be used in isolation, or in combination to better differentiate and diagnose disease.
[0021] In the field of medicine, imaging and image guidance are a significant component of clinical care. From diagnosis and monitoring of disease, to planning of the surgical approach, to guidance during procedures and follow-up after the procedure is SMI 408 Rowand LLP 313-complete, imaging and image guidance provides effective and multifaceted treatment approaches, for a variety of procedures, including surgery and radiation therapy. Targeted stem cell delivery, adaptive chemotherapy regimens, and radiation therapy are only a few examples of procedures utilizing imaging guidance in the medical field.
Optical tracking systems, used during a medical procedure, track the position of a part of the instrument that is within line-of-site of the optical tracking camera.
Optical tracking systems, used during a medical procedure, track the position of a part of the instrument that is within line-of-site of the optical tracking camera.
[0022] In surgical operations in particular, optical tracking is useful for displaying a live real-time image that combines pre-operative scan data with instrument location. This can assist, for example, a neurosurgeon in guiding an instrument to a treatment location within the brain. An example of an image-guided surgical suite is shown in FIG. 1, which diagrammatically illustrates, in perspective view, a navigation system 200, such as a medical navigation system. The navigation system 200 is positioned in an operating room ("OR") to be used to guide a surgeon in conducting a surgical procedure. In this example, the navigation system 200 supports, facilitates, and enhances minimally-invasive access port based surgery using a minimally-invasive access port-based surgical procedure.
In this example, a surgeon 101 conducts a minimally-invasive access port based surgery on a subject, such as a patient 102, in an OR environment. The surgery may be a neurosurgery, as in this example. In these circumstances, the surgeon 101 is positioned proximate the head of the patient 102.
In this example, a surgeon 101 conducts a minimally-invasive access port based surgery on a subject, such as a patient 102, in an OR environment. The surgery may be a neurosurgery, as in this example. In these circumstances, the surgeon 101 is positioned proximate the head of the patient 102.
[0023] In addition to the navigation system 200, the operating room may contain other equipment, such as surgical tool trays, carts, and booms. Some of this equipment may feature surgical lights, oxygen or other gas supplies, anesthesia supplies, etc., depending on the nature of the surgery being performed.
[0024] Reference is now made to FIG. 2, which diagrammatically illustrates an example of the navigation system 200. The navigation system 200 may include an equipment tower 201, a tracking system 213, and at least one display device. e.g., a primary display device 211 and a secondary display device 205. The tracking system 213 may include optical imaging devices, e.g. cameras. In this example, the tracking system 213 includes two laterally spaced-apart cameras for stereoscopic vision. The camera may be a three-dimensional (3D) optical tracking stereo camera, such as a Northern Digital Imaging (NDI) SMI 408 Rowand LLP 313-optical tracking stereo camera, by way of example. The navigation system 200 may be used to track at least one instrument, such as a surgical instrument, e.g., an access port 206, for assisting the surgeon 101 during the surgical procedure.
[0025] In some embodiments, the navigation system 200 may further include a device positioning unit, also referred to as a drive unit 220, having a robotic arm 202 that supports an optical device, such as an optical scope 204 or camera. In the cast where the optical scope 204 includes an image sensor, like a camera, the view may be displayed on one of the displays 205, 211 to assist the surgeon 101 in navigation. The view may also be integrated with other data, including pre-surgical plan information, pre-surgical imaging (like MRI, CAT scan, or ultrasound imaging, for example), and may be registered on the basis of registration of the patient in the OR space and registration of the surgical equipment relative to the patient, as tracked by the navigation system 200. The navigation system 200 may also track surgical instruments, like the access port 206 or other tools, in the OR
space and may map models of those tools to a virtual space to which patient data has been mapped in order to render a combined display of the tools and the patient and/or pre-surgical imaging on the displays 205, 211.
space and may map models of those tools to a virtual space to which patient data has been mapped in order to render a combined display of the tools and the patient and/or pre-surgical imaging on the displays 205, 211.
[0026] The equipment tower 201 may be mountable on a frame, e.g., a rack or a cart, and is configured to accommodate at least one of a computer operable by at least one a set of instructions, storable in relation to at least one non-transitory memory device, corresponding to at least one of planning software, navigation software, and robotic software, and a power supply, e.g., an AC adapter power supply.
[0027] In some example surgeries, a patient's head may be retained by a head holder 217, a craniotomy is performed, a dura flap is formed and retracted, and the access port 206 is inserted into the patient's brain. The tracking system 213 tracks and determines, e.g., in real-time by way of a set of instructions corresponding to tracking software and storable in relation to at least one non-transitory memory device, location data of at least one OR item, such as the robotic arm 202 and the at least one instrument, e.g., the access port 206. The tracked instrument may include at least one fiducial marker 212 mounted in fixed relation to the at least one OR item, e.g., the robotic arm 202 and the at least one instrument, e.g., the access port 206.
SMI 408 Rowand LLP 313-
SMI 408 Rowand LLP 313-
[0028] The secondary display device 205 may be configured to display real-time output from the navigation system 200. The displayed data may include at least one of an axial view, a sagittal view, at least one coronal view, and a view oriented relative to the at least one instrument, such as perpendicular to a tool tip, in-plane of a tool shaft, etc. The display may include multiple views.
[0029] The fiducial marker 212 may be a reflective sphere where the tracking system 213 is an optical tracking device. In some embodiments, the tracking system 213 may detect electromagnetic emissions arid the fiducial marker 212 may be an electromagnetic marker.
The three-dimensional position of the at least one fiducial marker 212 is determined by the tracking system 213 which is then able to map the location of the fiducial marker 212 to a virtual coordinate space and, thereby, position a model of the instillment to which the fiducial marker 212 is attached in the virtual coordinate space. The marker positions could be tracked relative to an object in the operating room such as the patient. Other types of markers that could be used would be radio frequency ("RF"), electro-magnetic ("EM"), light emitting diodes ("LED") (pulsed and un-pulsed), glass spheres, reflective stickers, or unique structures and patterns. The RF and EM may have specific signatures for the specific tools to which they are attached. The reflective stickers, structures, and patterns, glass spheres, LEDs may be detected using optical detectors, while RF and EM may be detected by using antennas.
The three-dimensional position of the at least one fiducial marker 212 is determined by the tracking system 213 which is then able to map the location of the fiducial marker 212 to a virtual coordinate space and, thereby, position a model of the instillment to which the fiducial marker 212 is attached in the virtual coordinate space. The marker positions could be tracked relative to an object in the operating room such as the patient. Other types of markers that could be used would be radio frequency ("RF"), electro-magnetic ("EM"), light emitting diodes ("LED") (pulsed and un-pulsed), glass spheres, reflective stickers, or unique structures and patterns. The RF and EM may have specific signatures for the specific tools to which they are attached. The reflective stickers, structures, and patterns, glass spheres, LEDs may be detected using optical detectors, while RF and EM may be detected by using antennas.
[0030] In the case of surgical navigation systems, registration is also important to ensure that the location of the patient is determined in terms of its position in the coordinate system. Then the system is accurately able to track the location of objects relative to the patient. That registration process, in various implementations, can be performed in relation to a base reference frame and is performable by various techniques, such as (a) identifying features (natural or engineered) on the MRI and CT images and pointing to those same features in the live scene using a pointer tool that is tracked by the tracking system; (b) tracing a line on the curved profile of the patient's anatomy with a pointer tool that is tracked by the tracking system and matching this curved profile to the 3D MRI or CT
volume; (c) applying a tool of known geometry to the patient's anatomy, where the tool is trackable by the tracking system; and (d) using a surface acquisition tool based on structured light or a 3D
scanner and matching an extracted surface to the 3D MRI or CT volume. As an example, registration using fiducial touch-points may include first identifying fiducial touch-points on Smi 408 Rowand LLP 313-images, then touching the ficlucial touch-points with a tracked instrument and determining registration data in relation to reference markers. In another example, the registration may involve conducting a surface scan procedure by scanning the patient's anatomy using a 3D
scanner, extracting the surface data from MRI/CT data, and determining registration data points by matching the surface data from the 3D scanner with the surface data from MRUCT
data. These techniques may be used in tandem to complete a registration. In some procedures, an initial registration may be supplemented or refined with additional registration operations during the course of a surgery.
volume; (c) applying a tool of known geometry to the patient's anatomy, where the tool is trackable by the tracking system; and (d) using a surface acquisition tool based on structured light or a 3D
scanner and matching an extracted surface to the 3D MRI or CT volume. As an example, registration using fiducial touch-points may include first identifying fiducial touch-points on Smi 408 Rowand LLP 313-images, then touching the ficlucial touch-points with a tracked instrument and determining registration data in relation to reference markers. In another example, the registration may involve conducting a surface scan procedure by scanning the patient's anatomy using a 3D
scanner, extracting the surface data from MRI/CT data, and determining registration data points by matching the surface data from the 3D scanner with the surface data from MRUCT
data. These techniques may be used in tandem to complete a registration. In some procedures, an initial registration may be supplemented or refined with additional registration operations during the course of a surgery.
[0031] Registration typically includes identifying the location of the patient anatomy relative to an optically-tracked patient reference device or marker that can be tracked by the navigation system and which is in a fixed position relative to the patient anatomy of interest.
Generally, this may be accomplished by attaching the patient reference device to a patient immobilization frame (such as a clamp for skull fixation in neurosurgery), which itself is rigidly attached to the patient. The patient reference device is typically a unique optical array, such as a fixed geometric pattern or arrangement of fiducials, that serves as a reference point for the navigation system. The registration process links the optically-detected location of the patient reference device to the optically-detected location of various landmarks or known points on the patient using one or more of the techniques described above by determining the three-dimensional location of both in the navigation coordinate system.
Generally, this may be accomplished by attaching the patient reference device to a patient immobilization frame (such as a clamp for skull fixation in neurosurgery), which itself is rigidly attached to the patient. The patient reference device is typically a unique optical array, such as a fixed geometric pattern or arrangement of fiducials, that serves as a reference point for the navigation system. The registration process links the optically-detected location of the patient reference device to the optically-detected location of various landmarks or known points on the patient using one or more of the techniques described above by determining the three-dimensional location of both in the navigation coordinate system.
[0032] After registration, the patient reference device is used by the optical navigation system to pinpoint the location of the patient in the coordinate system so that it can track the position of trackable objects relative to the patient.
[0033] Because the patient reference device is typically a physical structure protruding outwards and in close proximity to the patient, there is a risk that the patient reference device may be bumped or dislodged during the surgical operation. If this occurs, the surgical operation may need to be stopped to redo the registration process. Alternatively, the surgical operation may be continued without relying on the navigation system any further.
In some cases, the misalignment may be slight enough not to be noticed by persons in the operating room and the procedure might inadvertently be carried out in reliance on the navigation system which has now lost registration with the actual anatomical location of the SMI 408 Rowand LLP 313-patient. The phrase "lost registration", in many embodiments, may refer to a reduction in the accuracy of the registration below a defined threshold minimum accuracy.
In some cases, the misalignment may be slight enough not to be noticed by persons in the operating room and the procedure might inadvertently be carried out in reliance on the navigation system which has now lost registration with the actual anatomical location of the SMI 408 Rowand LLP 313-patient. The phrase "lost registration", in many embodiments, may refer to a reduction in the accuracy of the registration below a defined threshold minimum accuracy.
[0034] Some types of surgeries do not include an equivalent to the head clamp that immobilizes the patient's cranium during neurosurgery. For example, in some orthopedic surgeries, the patient may be only partly immobilized and portions of the patient anatomy may be expected to be manipulable during the surgery. In some such cases, the patient reference device may be directly attached to the patient anatomy. For example in some cases the patient reference device may be attached to bone using a drill and screws to secure the patient reference device in place relative to the patient anatomy.
[0035] Screw-based attachment may not be suitable for some surgeries, such as, for example sonic spinal surgeries. In some such cases, attachment of the patient reference device to patient anatomy is by way of another attachment mechanism, such as a mechanical clamp with jaws that can be secured to a bony structure, adhesive (to bone or skin), or a pin or other penetrating device. In some spinal surgeries, the patient reference device might be intended to be attached to certain vertebrae that are expected to stay (more or less) stationary during the surgery. In some cases, the attachment is to the lumbar vertebrae.
[0036] It will be appreciated that if the attachment mechanism is a clamp, adhesive or other such attachment mechanism, as opposed to screws/bolts, then there is a chance that bumping of the patient reference device may more easily dislodge or at least shift the position of the attachment mechanism, even where the patient reference device itself is not bent or broken. This becomes that much more difficult to identify in the case of a surgical operation in which the patient anatomy is not fully immobilized. It may be unclear whether the patient has moved or whether the patient reference device has moved relative to the patient. The latter would necessitate re-attachment and re-registration.
[0037] The present application describes a multi-piece patient reference device having an attachment base to be detachably secured to patient anatomical feature and an optically-trackable array that is detachably secured to the attachment base.
In some cases, the optically-trackable array may be attached using a quick-break attachment that allows the array to be knocked off relatively easily if bumped so as to ensure that no bumping forces are transferred to the attachment base. This helps avoid bumping and dislodgement or SMI 408 Ro wand LLP 313-disturbance of the attachment base relative to the anatomy, so that the optically-trackable array may be easily reattached, via the quick-break attachment, without necessitating a re-registration. In some cases, the quick-break attachment is a magnetic coupling between the attachment base and the optically-trackable array. The attachment base may feature a relatively low profile to ensure that it is unlikely to be bumped accidentally.
In some cases, the optically-trackable array may be attached using a quick-break attachment that allows the array to be knocked off relatively easily if bumped so as to ensure that no bumping forces are transferred to the attachment base. This helps avoid bumping and dislodgement or SMI 408 Ro wand LLP 313-disturbance of the attachment base relative to the anatomy, so that the optically-trackable array may be easily reattached, via the quick-break attachment, without necessitating a re-registration. In some cases, the quick-break attachment is a magnetic coupling between the attachment base and the optically-trackable array. The attachment base may feature a relatively low profile to ensure that it is unlikely to be bumped accidentally.
[0038] In some embodiments, the attachment base may include an inertial measurement unit ("IMU") to detect movement of the attachment base. In some implementations the inertial measurement unit includes one or more accelerometers and gyroscopes. In some embodiments, the IMU includes one or more magnetometers, which help with correcting for orientation drift. A typical example IMU may include three accelerometers arranged orthogonally to each other for measuring inertial acceleration, and three gyroscopes arranged orthogonally to each other to measure rotational position.
References herein to an IMU include an Attitude and Heading Reference System (AHRS), which typically includes an IMU and some on-board processing. The IMU, together with a logic circuit for detecting more than a threshold change in IMU measurements, may allow for determination of whether the attachment base has moved. The attachment base may include an output device that may signal, perhaps visually or audibly, when the attachment base has moved. In this manner, if the optically-trackable array is bumped and detached from the attachment base, before reattaching it and relying on it without requiring re-registration, the surgeon or other operating room personnel can confirm that the attachment base has not moved.
References herein to an IMU include an Attitude and Heading Reference System (AHRS), which typically includes an IMU and some on-board processing. The IMU, together with a logic circuit for detecting more than a threshold change in IMU measurements, may allow for determination of whether the attachment base has moved. The attachment base may include an output device that may signal, perhaps visually or audibly, when the attachment base has moved. In this manner, if the optically-trackable array is bumped and detached from the attachment base, before reattaching it and relying on it without requiring re-registration, the surgeon or other operating room personnel can confirm that the attachment base has not moved.
[0039] It will be appreciated that the attachment base may move relative to the patient anatomy or the patient anatomy may move causing movement of the attachment base. In some embodiments, this movement is indistinguishable to the attachment base.
In fact, during a surgical procedure the patient anatomy may be intentionally moved. In that case, the IMU may be "reset" so as to treat the newly-moved stationary position of the anatomy as the "zero" location from which future movement will be detected.
In fact, during a surgical procedure the patient anatomy may be intentionally moved. In that case, the IMU may be "reset" so as to treat the newly-moved stationary position of the anatomy as the "zero" location from which future movement will be detected.
[0040] In some cases, the output device may include a visual output, such as an LED
for example, an auditory output, such as a speaker, or a wireless communications output to an external device that will generate a visual or auditory alarm.
SMI 408 Rowand LLP 313-
for example, an auditory output, such as a speaker, or a wireless communications output to an external device that will generate a visual or auditory alarm.
SMI 408 Rowand LLP 313-
[0041] Reference is now made to FIG. 3, which shows a perspective view of one example embodiment of a multi-part patient reference device 300. The device 300 includes an optically-trackable array 302 and an attachment base 304. In this embodiment, the attachment base 304 includes a clamp mechanism 306 for securing the attachment base 304 to a bony structure, such as the spinous process, for example.
[0042] The attachment base 304 further includes a housing 308. The top of the housing 308 includes a quick-break attachment mechanism 310. The quick-break attachment mechanism 310 may include any coupling mechanism for attaching and securing the optically-trackable array 302 to the attachment base 304 in such a manner that it is secured in place in a pre-ordained orientation so that it may only be re-attached in exactly the same orientation and position. The quick-break attachment mechanism 310 may include a channel, slot, or other protrusion-groove structure to physically orient the optically-trackable array 302 to as to protrude outwards from the top of the housing 308. The channel, slot, etc., may be keyed to ensure proper orientation in a pre-determined position. The quick-break mechanism may include a magnetic connection to hold the optically-trackable array 302 in position on the attachment base 304 unless at least a threshold level of force overcomes the quick-break connection. The magnetic connection, which may be implemented as one or more permanent magnets in either side of the quick-break attachment mechanism 310, ensures a coupling force acts on the attachment base 304 and optically-trackable array 302 holding them in alignment and in connection. The level of force exerted by the quick-break attachment mechanism 310 is to be sufficient to ensure the optically-trackable array 302 is not too easily detached, such as by gravitational forces or minimal impact forces, but not so solidly attached that it will not detach in the case of an impact force that could risk dislodging the attachment base 304 from patient anatomy.
That is the detachment force capable of overcoming the quick-break mechanism should be substantially lower than the force capable of dislodging the clamp mechanism 306 (or other attachment mechanism in other embodiments) from the patient anatomy. The term "quick-coupling" may be used interchangeably with "quick-break".
That is the detachment force capable of overcoming the quick-break mechanism should be substantially lower than the force capable of dislodging the clamp mechanism 306 (or other attachment mechanism in other embodiments) from the patient anatomy. The term "quick-coupling" may be used interchangeably with "quick-break".
[0043] The optically-trackable array 302 includes a geometric arrangement of fiducials 312 mounted on a stem 314 or longitudinally-extending arm that protrudes away from the attachment base 304. Other arrangements of fiducial 312, whether on a frame structure or on another substrate, may be used in other embodiments. The stem 314 functions to position the fiducials 312 spaced apart from the anatomy to make them more consistently and easily visible to tracking devices, e.g. cameras, of the navigation system during the surgical operation. In the case of a spinal surgery, particularly if there is more than one patient reference device being used in an operation (e.g. each attached to different vertebrae), the horizontally-compact vertically-oriented structure of the patient reference device 300 improves its usefulness in the surgical suite and reduces the likelihood of it being accidentally bumped because it obscures an area of interest. In this regard, it will be noted that the example patient reference device 300 is vertically aligned, such that the clamp mechanism 306, housing 308, and optically-trackable array 302 are all generally aligned along a common vertical axis.
[0044] Reference is now made to FIG. 4, which shows, diagrammatically one example embodiment of the attachment base 304. In this example embodiment, the attachment base 304 has a housing 308 that includes within it a battery 320, an IMU 322, a logic circuit 324 and all output device 326.
[0045] The IMU 322 generates signals, i.e. a motion signal, indicative of measured inertial forces on the attachment base 304. Together, the logic circuit 324 and the IMU 322 detect whether the attachment base 304 experiences more than a threshold change in position (rotation) or more than a threshold change in inertial acceleration forces (including gravitational forces, which could indicate positional change or rotation). The measured forces of the IMU 322 result in signals that may be comparted with a threshold by the logic circuit 324 and more than a threshold change in the IMU 322 measurements may trigger generation of an alarm signal that causes the output device 326 to output an alarm. Output of the alarm signal may be referred to as an alarm condition for the patient reference device. It will be appreciated that in some embodiments the IMU 322 and the logic circuit 324 may be considered an integral unit and may be implemented as a single integrated circuit component.
The setting of a suitable threshold for determining that a detectable change has occurred may be implementation specific and may be altered to suit a particular sensitivity. The threshold level may be related to the relative positional change that such a movement would cause in the position, orientation, etc. of the trackable optical array, and may be set based on it causing more than a particular change in the position of the array, such as 0.5%, 1%, 3%, etc., or may SMI 408 Rowand I,LP 313-be based on it causing an overall movement of more than a threshold distance by a point on the array, such as Imm, 2mm, 5mm, etc.
The setting of a suitable threshold for determining that a detectable change has occurred may be implementation specific and may be altered to suit a particular sensitivity. The threshold level may be related to the relative positional change that such a movement would cause in the position, orientation, etc. of the trackable optical array, and may be set based on it causing more than a particular change in the position of the array, such as 0.5%, 1%, 3%, etc., or may SMI 408 Rowand I,LP 313-be based on it causing an overall movement of more than a threshold distance by a point on the array, such as Imm, 2mm, 5mm, etc.
[0046] The output device 326 may include one or more LEDs or other such light output devices for signaling the alarm. In one example implementation, when the IMU 322 reaches a steady state, i.e. holds a stationary position, for at least a minimum time (e.g. 20-60 seconds, a few minutes, or longer), a green LED may be illuminated indicating that the attachment base 30 is in a stable stationary position. Upon detecting more than a threshold amount of movement, the IMU 322 and logic circuit 324 may cause illumination of the green LED to cease and may cause illumination of a red LED to indicate that the attachment base 304 has moved. To ensure the "moved" condition is not missed, in some other embodiments, the attachment base 304 may include an input device, such a button, switch, touch sensitive area, or other input mechanism (not illustrated) for receiving a reset command so that the attachment base 304 continues to display a "moved" red LED condition until it is manually reset.
[0047] In some embodiments, the output device 326 may include a speaker or other audio output mechanism for emitting an alarm sound in response to the alarm signal from the IMU 322 and logic circuit 324. The alarm sound may be a constant tone or series of tones, intermittent chirping, or any other audible alarm that will alert personnel in the operating room to the fact the attachment base 304 has moved.
[0048] In some embodiments, the attachment base 304 may include both the audible alarm and the visible alarm.
[0049] In yet other embodiments, the output device 326 includes a wireless communication system for transmitting the alarm signal to a remote device, which then outputs an alarm. For example, the wireless communication system may include a WiFi chip, a BluetoothTM chip, a Near-Field Communications ("NFC") chip, or any other short-range RF
wireless system for establishing a communications channel with another device.
In another example, the wireless communication may be by RFID, whether active or passive, in which the navigation system polls one or more patient reference devices for information on the status of the device, i.e. whether an alarm state is active. If the output device 326 includes wireless communication capability, then any applicable "reset" command may be sent to the SMI 408 Rowand LLP 313-attachment base 304 over the communications channel from the remote device to which the wireless system is connected in order to cancel or reset the alarm condition.
wireless system for establishing a communications channel with another device.
In another example, the wireless communication may be by RFID, whether active or passive, in which the navigation system polls one or more patient reference devices for information on the status of the device, i.e. whether an alarm state is active. If the output device 326 includes wireless communication capability, then any applicable "reset" command may be sent to the SMI 408 Rowand LLP 313-attachment base 304 over the communications channel from the remote device to which the wireless system is connected in order to cancel or reset the alarm condition.
[0050] Although the present example embodiment shows the attachment mechanism to be the clamp mechanism 306, other mechanisms for securing the attachment base 304 to patient anatomy may be used in other implementations. The clamp mechanism 306 may be useful in the case of spinal surgeries since the jaws of the clamp mechanism 306 may grip the protruding spinous process of a vertebrae. Nevertheless, in some cases adhesive, bone screws, or other attachment mechanisms may be considered advantageous in place of a physical clamp.
[0051] Reference is now made to Figure 5, which shows another example embodiment of an attachment base 404 for a patient reference device. In this example embodiment, the attachment base 404 is a two-part device that includes a sensor base 420 and a detachable battery housing 410. The battery housing 410 is designed to securely attach to the top of the sensor base 420. The top of the battery housing 410 includes one side of the quick-break attachment mechanism 310 for connecting the optically-trackable array. The underside of the battery housing 410 may feature contacts 412, 414 that are electrically connected to respective terminals of the battery 320 within the battery housing 410.
[0052] The sensor base 420 includes the IMU 322, the logic circuit 324 and the output device 326. It features an attachment mechanism 430 for securing the attachment base 404 to patient anatomy. The attachment mechanism 430 is illustrated generally and may include various attachments including mechanical clamps, pins, adhesive or other suitable attachment means.
[0053] The sensor base 420 includes an external casing with a top side that features contact pads 422 and 424 for electrically connecting to contacts 412 and 414, respectively.
One or both of the contact pads 422, 424 or contacts 412, 414 may include a mechanical biasing, e.g. spring loading, to ensure solid contact when connected. The casings of the sensor base 420 and battery housing 410 feature a coupling mechanism that ensures the casings are securely attached in a fixed alignment and position relative to each other. In the present illustration, the coupling mechanism is depicted as a snap-fit mechanism but other attachment mechanisms may be used for other implementations.
SmI 408 Rowand LLP 313-
One or both of the contact pads 422, 424 or contacts 412, 414 may include a mechanical biasing, e.g. spring loading, to ensure solid contact when connected. The casings of the sensor base 420 and battery housing 410 feature a coupling mechanism that ensures the casings are securely attached in a fixed alignment and position relative to each other. In the present illustration, the coupling mechanism is depicted as a snap-fit mechanism but other attachment mechanisms may be used for other implementations.
SmI 408 Rowand LLP 313-
[0054] One advantage of a two-part attachment base 404 is that the battery in the detachable battery housing 410 is separable from the sensor base 420. The sensor base 402 may contain relatively costly components, but the battery may be largely disposable. The sensor base 402 may be sterilized for re-use in subsequent surgical operations, whereas the detachable battery housing 410 may be disposed after use, since the battery may not be easily sterilized in some cases.
[0055] This example embodiment also shows the sensor base 420 including a reset input device 440, which in some examples may include a button or other manually-activated input mechanism. The reset input device 440 functions to send a signal to the IMU 322 and logic circuit 324 that causes them to start the operation of determining whether the attachment base 404 has moved more than a threshold amount based on the current inertial measurements. That is, the reset input device 440, when activated, signals that the attachment base 404 is in a stationary state and that any subsequent movement beyond the threshold level should cause an alarm. If any alarm is currently being output, then a signal from the reset input device 440 causes the alarm to cease until the IMU 322 and logic circuit 324 detect another indication of movement beyond the threshold level.
[0056] Another embodiment of an example battery housing 450 is shown in FIG. 6.
In this embodiment, the battery housing 450 includes additional battery contacts 452, 454 on the top of its casing to enable electrical DC power connection to the optically-trackable array.
The additional battery contacts 452, 454 may be implemented as a part of the quick-break attachment mechanism 310 in some embodiments. Battery power may be used by the optically-trackable array in some implementations to power active fiducials, e.g. infrared LED-based fiducials, that emit energy as part of their function in assisting the navigation system to uniquely identify and track the optically-trackable array. In some cases, the active fiducials may include fiducials that emit light at different wavelengths in order to be distinguishable to the navigation system. The fiducials may be configured, internally or based on circuit elements in the optically-trackable array, to transmit light using a defined pattern or pulse frequency to further enable the navigation system to uniquely identify each fiducial. In yet other cases, the optically-trackable array may include logic circuitry or other computing elements to enable control of the active fiducials so as to receive optical communications from the navigation system and/or to transmit communications to the SMI 408 Rowand LLP 313-navigation system. Example communications may be receiving, possibly addressed, instructions regarding pulse patterns to use, or transmitting status information, such as battery level information.
In this embodiment, the battery housing 450 includes additional battery contacts 452, 454 on the top of its casing to enable electrical DC power connection to the optically-trackable array.
The additional battery contacts 452, 454 may be implemented as a part of the quick-break attachment mechanism 310 in some embodiments. Battery power may be used by the optically-trackable array in some implementations to power active fiducials, e.g. infrared LED-based fiducials, that emit energy as part of their function in assisting the navigation system to uniquely identify and track the optically-trackable array. In some cases, the active fiducials may include fiducials that emit light at different wavelengths in order to be distinguishable to the navigation system. The fiducials may be configured, internally or based on circuit elements in the optically-trackable array, to transmit light using a defined pattern or pulse frequency to further enable the navigation system to uniquely identify each fiducial. In yet other cases, the optically-trackable array may include logic circuitry or other computing elements to enable control of the active fiducials so as to receive optical communications from the navigation system and/or to transmit communications to the SMI 408 Rowand LLP 313-navigation system. Example communications may be receiving, possibly addressed, instructions regarding pulse patterns to use, or transmitting status information, such as battery level information.
[0057] In yet another embodiment, an example attachment base, in one or two parts, may contain the IMU, a battery and a wireless communication system. The attachment base may be configured to send IMU data to a navigation system regularly. The navigation system determines whether the IMU data indicates movement or not, and the navigation system outputs any alarms required as a result of detected movement of the attachment base.
[0058] Reference is now made to FIG. 7, which shows, in simplified flowchart form, one example method 600 for tracking patient anatomy during a surgical operation. The method 600 is carried out using a patient reference device, such as the example patient reference device 300 (FIG. 3) described above. In the operating room and in the course of surgery, the patient reference device 300 may be used to track patient anatomy. The patient anatomy may include anatomy that is intended to remain stationary during the operation, such as a hip, cranium, portion of the spine, etc., depending on the nature of the operation. In the present example, the patient reference device is to be attached to a vertebrae and, in particular, to the spinous process of a vertebrae. Accordingly, in operation 602 the patient reference device is clamped to a vertebrae.
100591 In this example, the patient reference device is capable of receiving an input to trigger it to begin monitoring for movement. That is, it does not begin attempting to detect movement until instructed. That instruction or signal may be supplied via an input device, such a button or the like, that is actuated by personnel after the device is secured in place on the patient's anatomy. In some embodiments, that instruction may be communicated to the device wirelessly, where the device is equipped with a wireless communication system and capable of receiving such an instruction via RF or infrared communications, for example. In yet another embodiment, the instruction may be implemented simply as the supply of power;
that is, attachment of the battery housing to the sensor base is the trigger for the sensor base to begin detecting movement. As shown in FIG. 7, the method 600 includes determining whether to start monitoring for movement in operation 604.
smi 408 Rowand LLP 313-[0060] On determining that it is to start monitoring (by way of explicit instruction or command, or by way of implicit instruction, such as through supply of battery power), the device may then, in some embodiments, record current measurements from the IMU
in operation 606, for comparison against future measurements. As indicated by operation 608 the device assesses whether there has been a change greater than a threshold level. In some embodiments, the recordal of starting measurements is not performed, as the 1MU and logic circuitry simply attempt to detect a pseudo-instantaneous change in measurements that exceeds the threshold level. On the other hand in some embodiments the original measurements may be retained in order to detect relatively slow movements that, in time, result in more than a threshold change in position or orientation of the device.
[00611 If the device determines in operation 608 that the attachment base has undergone more than a threshold change in position or orientation, based on a more than threshold level change in the measurements of the IMU, then in operation 610 it outputs an alarm. As described above, the alarm may include a visual alarm, e.g. solid or flashing LED(s), an auditory alarm, e.g. speaker emitting tone or chirp, or a wireless communication to a remote device that signals the alarm. The alarm may include multiple types of alarms in combination in some cases.
[0062] In operation 612, the device determines whether the alarm has been cancelled and the device reset to a stationary position. Once that occurs, the process returns to operation 606 to monitor for movement.
[0063] In some cases, operation 612 may only involve stopping the alarm, and the process may return to operation 604 to await a further input command to re-start monitoring for movement. These commands may be input using the same input device or separate input devices. For example, a reset button may be pressed once to cancel the alarm output, but not restart the monitoring operation. After the device is repositioned and stationary, the reset button may be pressed again to trigger restarting of the monitoring operation, e.g. to progress from operation 604 to 606.
100641 Certain adaptations and modifications of the described embodiments can be made. Therefore, the above discussed embodiments are considered to be illustrative and not restrictive.
SMI 408 Rowand LLP 313-
100591 In this example, the patient reference device is capable of receiving an input to trigger it to begin monitoring for movement. That is, it does not begin attempting to detect movement until instructed. That instruction or signal may be supplied via an input device, such a button or the like, that is actuated by personnel after the device is secured in place on the patient's anatomy. In some embodiments, that instruction may be communicated to the device wirelessly, where the device is equipped with a wireless communication system and capable of receiving such an instruction via RF or infrared communications, for example. In yet another embodiment, the instruction may be implemented simply as the supply of power;
that is, attachment of the battery housing to the sensor base is the trigger for the sensor base to begin detecting movement. As shown in FIG. 7, the method 600 includes determining whether to start monitoring for movement in operation 604.
smi 408 Rowand LLP 313-[0060] On determining that it is to start monitoring (by way of explicit instruction or command, or by way of implicit instruction, such as through supply of battery power), the device may then, in some embodiments, record current measurements from the IMU
in operation 606, for comparison against future measurements. As indicated by operation 608 the device assesses whether there has been a change greater than a threshold level. In some embodiments, the recordal of starting measurements is not performed, as the 1MU and logic circuitry simply attempt to detect a pseudo-instantaneous change in measurements that exceeds the threshold level. On the other hand in some embodiments the original measurements may be retained in order to detect relatively slow movements that, in time, result in more than a threshold change in position or orientation of the device.
[00611 If the device determines in operation 608 that the attachment base has undergone more than a threshold change in position or orientation, based on a more than threshold level change in the measurements of the IMU, then in operation 610 it outputs an alarm. As described above, the alarm may include a visual alarm, e.g. solid or flashing LED(s), an auditory alarm, e.g. speaker emitting tone or chirp, or a wireless communication to a remote device that signals the alarm. The alarm may include multiple types of alarms in combination in some cases.
[0062] In operation 612, the device determines whether the alarm has been cancelled and the device reset to a stationary position. Once that occurs, the process returns to operation 606 to monitor for movement.
[0063] In some cases, operation 612 may only involve stopping the alarm, and the process may return to operation 604 to await a further input command to re-start monitoring for movement. These commands may be input using the same input device or separate input devices. For example, a reset button may be pressed once to cancel the alarm output, but not restart the monitoring operation. After the device is repositioned and stationary, the reset button may be pressed again to trigger restarting of the monitoring operation, e.g. to progress from operation 604 to 606.
100641 Certain adaptations and modifications of the described embodiments can be made. Therefore, the above discussed embodiments are considered to be illustrative and not restrictive.
SMI 408 Rowand LLP 313-
Claims (14)
1. A patient reference device for tracking anatomical location of a patient by an optical navigation system during a surgical procedure, the patient reference device comprising:
an attachment base having an attachment mechanism to secure the attachment base to an anatomical feature of the patient;
an optically-trackable array including a plurality of fiducials in a fixed geometric pattern to be detected by the optical navigation system and having a longitudinally-extending arm to space apart the fixed geometric pattern from the attachment base, the arm including a connector to be detachably secured to the attachment base, wherein the connector is a quick-coupling attachment mechanism;
an inertial measurement unit in the attachment base to detect a change in position of the attachment base and to output a motion signal representing the change in position and its magnitude;
a logic circuit to receive the motion signal and to compare it to a threshold level and, if the motion signal exceeds the threshold level, to generate an alarm signal; and an output device to output an alarm in response to the alarm signal.
an attachment base having an attachment mechanism to secure the attachment base to an anatomical feature of the patient;
an optically-trackable array including a plurality of fiducials in a fixed geometric pattern to be detected by the optical navigation system and having a longitudinally-extending arm to space apart the fixed geometric pattern from the attachment base, the arm including a connector to be detachably secured to the attachment base, wherein the connector is a quick-coupling attachment mechanism;
an inertial measurement unit in the attachment base to detect a change in position of the attachment base and to output a motion signal representing the change in position and its magnitude;
a logic circuit to receive the motion signal and to compare it to a threshold level and, if the motion signal exceeds the threshold level, to generate an alarm signal; and an output device to output an alarm in response to the alarm signal.
2. The patient reference device claimed in claim 1, wherein the quick-coupling attachment mechanism includes at least one magnet of a first polarity, and wherein the attachment base includes at least one corresponding magnet of an opposite polarity.
3. The patient reference device claimed in claim 1, wherein the attachment base includes a housing containing a battery, the inertial measurement unit, the logic circuit and the output device.
4. The patient reference device claimed in claim 1, wherein the attachment base includes a sensor base containing the inertial measurement unit, the logic circuit and the output device and a detachable battery housing containing a battery to power the sensor base.
5. The patient reference device claimed in claim 4, wherein a top of the sensor base includes electrical contact pads, and wherein a bottom of the battery housing includes electrical contacts connected to respective terminals of the battery, and wherein the electrical contacts make electrical connections with respective contact pads when the battery housing is attached to the sensor base.
6. The patient reference device claimed in claim 1, wherein the attachment mechanism comprises a clamp to secure the attachment base to the anatomical feature.
7. The patient reference device claimed in claim 1, further comprising a reset mechanism for generating a signal to the logic circuit to reset an alarm condition.
8. The patient reference device claimed in claim 1, wherein the output device includes at least one of a light emitting diode or a speaker.
9. The patient reference device claimed in claim 1, wherein the attachment base, attachment mechanism, and optically trackable array are arranged along a common axis to project away from the anatomical feature.
10. The patient reference device claimed in claim 1, wherein the output device comprises a wireless communication system to connect to an external device, and wherein the alarm comprises a communication to the external device, and the external device, in response thereto, outputs a visual or auditory alarm event.
11. The patient reference device claimed in claim 1, further comprising an input device to generate a signal to cause the logic circuit to begin comparing the motion signal to the threshold level.
12. The patient reference device claimed in claim 11, wherein the input device comprises a button.
13. The patient reference device claimed in claim 11, wherein, if the patient reference device is in an alarm condition, then actuation of the input device is to cancel the alarm condition and if the device is not in the alarm condition, then actuation of thc input device is to cause the logic circuit to begin comparing the motion signal to the threshold level.
14. The patient reference device claimed in claim 1, wherein the attachment base includes a battery, wherein the connector includes an electrical connection to supply battery power, and wherein the plurality of fiducials comprises at least one active fiducial to be powered by the battery power.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA2958013A CA2958013C (en) | 2017-02-15 | 2017-02-15 | Patient reference device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA2958013A CA2958013C (en) | 2017-02-15 | 2017-02-15 | Patient reference device |
Publications (2)
Publication Number | Publication Date |
---|---|
CA2958013A1 CA2958013A1 (en) | 2017-04-14 |
CA2958013C true CA2958013C (en) | 2019-01-15 |
Family
ID=58534662
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA2958013A Active CA2958013C (en) | 2017-02-15 | 2017-02-15 | Patient reference device |
Country Status (1)
Country | Link |
---|---|
CA (1) | CA2958013C (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10441365B2 (en) | 2017-01-11 | 2019-10-15 | Synaptive Medical (Barbados) Inc. | Patient reference device |
US10832408B2 (en) | 2017-10-26 | 2020-11-10 | Synaptive Medical (Barbados) Inc. | Patient registration systems, devices, and methods for a medical procedure |
CN113974786A (en) * | 2021-10-20 | 2022-01-28 | 深圳先进技术研究院 | Intracranial hematoma puncture drainage operation system punctured by mechanical arm |
-
2017
- 2017-02-15 CA CA2958013A patent/CA2958013C/en active Active
Also Published As
Publication number | Publication date |
---|---|
CA2958013A1 (en) | 2017-04-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US10441365B2 (en) | Patient reference device | |
US11819365B2 (en) | System and method for measuring depth of instrumentation | |
US11857266B2 (en) | System for a surveillance marker in robotic-assisted surgery | |
CN109276316B (en) | Robot operation platform | |
US20230037993A1 (en) | Surgical instrument and method for detecting the position of a surgical instrument | |
US20170172669A1 (en) | System and method for a surveillance marker in robotic-assisted surgery | |
US10646280B2 (en) | System and method for surgical tool insertion using multiaxis force and moment feedback | |
US11571265B2 (en) | System for neuronavigation registration and robotic trajectory guidance, robotic surgery, and related methods and devices | |
US20180325610A1 (en) | Methods for indicating and confirming a point of interest using surgical navigation systems | |
US20210169582A1 (en) | Navigation surgical system, registration method thereof and electronic device | |
US10869613B2 (en) | Medical guidance device | |
US10765480B2 (en) | Wireless active tracking fiducials | |
US8945130B2 (en) | Tool attachment for medical applications | |
US20070093709A1 (en) | Surgical navigation markers | |
EP3369394B1 (en) | System for a surveillance marker in robotic-assisted surgery | |
JP2017000771A (en) | Position adjustment device, and device and method for robot-assisted surgical operation | |
EP3223677A1 (en) | Model registration system and method | |
JP2009531113A (en) | Image guided surgery system | |
CA2958013C (en) | Patient reference device | |
EP3212104B1 (en) | Hybrid navigation system for surgical interventions | |
EP3318213B1 (en) | System for measuring depth of instrumentation | |
EP3847989A1 (en) | System for neuronavigation registration and robotic trajectory guidance, robotic surgery, and related methods and devices | |
US20240216080A1 (en) | System and method for a surveillance marker in robotic-assisted surgery | |
US20230083538A1 (en) | Robot surgical platform for cranial surgery | |
EP3426178B1 (en) | A system for navigated punction, biopsy or ablation comprising a needle-like instrument and a removable sensor carrier |