Three-dimensional mapping system and method for a craniotomy path with semi-targets

Abstract

The present invention provides methods and apparatuses for mapping and displaying a three-dimensional (3D) surgical path. An entry voxel and a target voxel are selected, as well as semi-target voxels between the entry voxel and the target voxel. When a voxel representing bone is between the entry voxel and the target voxel, the semi-target voxels are selected such that the voxel representing bone is not within the shortest line between the semi-target voxel and the entry voxel. A path is defined by a series of voxels passing through the semi-target voxels. For each voxel V in the series between one of the semi-target voxels and an endpoint voxel, the immediately succeeding voxel of voxel V is selected from the group of adjacent voxels of voxel V by comparing the selection weights of each voxel, which are determined on the basis of a selected set including relative distances with respect to the endpoint voxel and the semi-target voxels. The path voxels are selectively highlighted in a display view to provide visualization of the 3D surgical path.

Description

Technical Field

[0001] This patent application provides systems, devices, and methods for improving medical procedures. Background Art

[0002] Visualization of in-vivo structures can be performed by mapping the propagation of excitation waves. Fluoroscopy, computed tomography (CT), ultrasound, magnetic resonance imaging (MRI), and other techniques can be used to provide visualization and graphical rendering of in-vivo structures.

[0003] Typically, the visualization and graphical rendering of in-vivo structures consists of voxels of 3D scanned images; a voxel is imaging data of selected coordinates of a particular slice of the scan. For example, a cranial CT scan can produce a series of image "slices" of a subject's head, which are composed of voxels of imaging data, and each voxel represents a type of material (such as bone, tissue, air, etc.). The scanned slices are combined in sequence to produce a 3D scanned image of the subject's head and its internal and external structures from the cranial scan.

[0004] Typically, the type of material represented by the voxels is determined by applying selected analysis criteria to the scan data, such as applying the well-known Hounsfield scale. Then, color or grayscale weights can be selected to correspond to the determined representative material, so as to present a true image of the scanned skull on a display device.

[0005] By using modern computer processors, which may include a central processing unit (CPU) and a graphics processing unit (GPU), a user can operate a display device to view almost any cross-section or perspective view of the 3D scanned image of the skull obtained from the scan data. Such views can also be printed as needed, including using 3D printing technology to produce an actual 3D rendering.

[0006] Multiple conditions require surgery inside a subject's skull. For example, an ear, nose, and throat (ENT) doctor can diagnose a disease that requires surgery in a relatively remote part of a patient's sinus.

[0007] To prepare for such surgery, it is desirable to provide a visualization and three-dimensional (3D) map of a path to the surgical site. This path is a path through which a surgical tool can be inserted, and the surgical tool is used for performing non-invasive surgery on a remote surgery inside the skull, where the path does not pass through bone, tissue, or other such barriers. Although there may be multiple such paths, while keeping as far away from bone as possible, it is preferable to select a relatively short path. Summary of the Invention

[0008] Methods, apparatus, and systems are provided for mapping and displaying a three-dimensional (3D) surgical path within a displayed image of a cranial structure derived from voxels of a cranial scan of a subject.

[0009] In the exemplary method, the initial entry voxel Vx is selected e ,y e ,z e and surgical site target voxel Vx t ,y t ,z t Then, the initial entry voxel Vx is also selected e ,y e ,z e and surgical site target voxel Vx t ,y t ,z t The half-target voxel Vx between st ,y st ,z st The voxel representing the bone is located at the initial entry voxel Vx e, y e, z e and surgical site target voxel Vx t, y t, z t In the case of the shortest line between the two, it is preferred to initially enter the voxel Vx e ,y e ,z e and surgical site target voxel Vx t ,y t ,z t The half-target voxel Vx between st ,y st ,z st The choice of Vx is such that the voxels representing bones do not initially enter the voxel Vx. e, y e, z e and half-target voxel Vx st ,y st ,z st Within the shortest line between.

[0010] For the half-target voxel Vx st ,y st ,z st A series of voxels are mapped so that the voxel Vx e ,y e ,z e and target voxel Vx t ,y t ,z tEach voxel between is an adjacent voxel of both the immediately preceding voxel and the immediately following voxel in the series to define a 3D surgical path.

[0011] For each voxel Vx e , y e , z e in the series between the initial entry voxel Vx st , y st , z st and the semi-target voxel Vx i, y i, z i , the immediately following voxel of the voxel Vx i, y i, z i is selected from the group of adjacent voxels of the voxel Vx i, y i, z i . The selection includes determining a selection weight for each voxel in the group of adjacent voxels on a selected basis, the selected basis including the relative distances with respect to the entry voxel Vx e, y e, z e and the semi-target voxel Vx st , y st , z st . Then, the immediately following voxel of the voxel Vx i, y i, z i is selected based on a comparison of the determined selection weights.

[0012] For each voxel Vx st , y st , z st in the series between the semi-target voxel Vx t, y t, z t and the target voxel Vx j, y j, z j , the immediately following voxel of the voxel Vx j, y j, z j is selected from the group of adjacent voxels of the voxel Vx j, y j, z j . The selection includes determining a selection weight for each voxel in the group of adjacent voxels on a selected basis, the selected basis including the relative distances with respect to the semi-target voxel Vx st , y st , z st and the target voxel Vx t, y t, z tThe relative distance. Then, based on the comparison of the determined selection weights, voxel Vx is selected. j, y j, z j The immediately succeeding voxel.

[0013] In the display view of the cranial structure, the voxels of the determined 3D surgical path are selectively highlighted to provide visualization of the 3D surgical path. Selectively highlighting the voxels of the 3D surgical path in the display view of the cranial structure may include applying different highlighting to the voxels of the part of the 3D surgical path hidden in the display view.

[0014] For each voxel Vx in the series i, y i, z i , voxel Vx i, y i, z i The immediately succeeding voxel can be selected from the group of adjacent voxels of voxel Vx i, y i, z i that does not include the adjacent voxels of the immediately preceding voxel of voxel Vx i, y i, z i In addition, the determination of the selection weights of the adjacent voxels of each voxel Vx i, y i, z i can include a penalty value based on the relative distance from the voxels representing at least a certain threshold density within a predetermined distance.

[0015] Similarly, for each voxel Vx in the series j, y j, z j , voxel Vx j, y j, z j The immediately succeeding voxel can be selected from the group of adjacent voxels of voxel Vx j, y j, z j that does not include the adjacent voxels of the immediately preceding voxel of voxel Vx j, y j, z j In addition, the determination of the selection weights of the adjacent voxels of each voxel Vx j, y j, z j can include a penalty value based on the relative distance from the voxels representing at least the threshold density within a predetermined distance.

[0016] In one example, the threshold density is set to negative five hundred (-500) Hu, and the predetermined distance is 0.8 mm. In another example, the threshold density is set to bone density.

[0017] The method can also include using a display view of a 3D surgical path to insert the distal end of a catheter into the skull of a subject starting from the physical location corresponding to the initial entry voxel Vx e ,y e ,z e along the 3D surgical path to deploy the distal end of the catheter to the physical location corresponding to the target voxel Vx t, ,y t ,z t of the surgical site.

[0018] The path can be determined starting from the entry voxel Vx e, y e, z e In this case, the selection weight of each voxel in the adjacent voxel group of each voxel Vx i, y i, z i can include the relative proximity to the entry voxel Vx e, y e, z e and the relative distance to the semi-target voxel Vx st ,y st ,z st Similarly, the selection weight of each voxel in the adjacent voxel group of each voxel Vx j, y j, z j can include the relative proximity to the semi-target voxel Vx st ,y st ,z st and the relative distance to the target voxel Vx t ,y t ,z t of the surgical site.

[0019] The path can also be determined starting from the target voxel Vx t, y t, z t In this case, the selection weight of each voxel in the adjacent voxel group of each voxel Vx i, y i, z i can include the relative distance to the entry voxel Vx e, y e, z e and the relative proximity to the semi-target voxel Vxst ,y st ,z st Similarly, each voxel Vx is determined based on the selected j, y j, z j The selection weight of each voxel in the neighboring voxel group may include the weight of the semi-target voxel Vx st ,y st ,z st The relative distance to the target voxel Vx t ,y t ,z t relative proximity.

[0020] An example apparatus for mapping and displaying a three-dimensional (3D) surgical path within a cranial structure derived from voxels of a cranial scan of a subject includes a processor and associated data storage, a display, and a voxel selection device. The data storage is configured to store voxels of the cranial scan of the subject. The processor and associated display are configured to provide cross-sectional and 3D imaging of the cranial structure of the subject based on the cranial scan. The voxel selection device is configured for a user to select an initial entry voxel Vx e ,y e ,z e and surgical site target voxel Vx t ,y t ,z t , and is configured for user selection of the initial entry voxel Vx e ,y e ,z e and surgical site target voxel Vx t ,y t ,z t The half-target voxel Vx between st ,y st ,z st .

[0021] The processor is further configured to include a half-target voxel Vx st ,y st ,z st A series of voxels are mapped so that the voxel Vx e, y e, z e and target voxel Vx t, y t, z t Each voxel in between is a neighbor to both the immediately preceding voxel and the immediately following voxel in the series to define the 3D surgical path.

[0022] For the voxel Vx e, ye, z e and half-target voxel Vx st ,y st ,z st Each voxel Vx in the series between i, y i, z i , the processor is configured to extract the voxel Vx i, y i, z i Select voxel Vx from the adjacent voxel group i, y i, z i The selection is performed by determining a selection weight for each voxel in the set of neighboring voxels based on a selection including the weight of the voxel relative to the incoming voxel Vx. e, y e, z e and half-target voxel Vx st ,y st ,z st The relative distance is then used to select the voxel Vx based on the comparison of the determined selection weights. i, y i, z i The voxel that follows .

[0023] For the half-target voxel Vx st ,y st ,z st and target voxel Vx t, y t, z t Each voxel in the series Vx j, y j, z j , the processor is configured to extract the voxel Vx j, y j, z j Select voxel Vx from the adjacent voxel group j, y j, z j The selection is then performed by determining a selection weight for each voxel in the set of neighboring voxels based on a selection including the weight relative to the semi-target voxel Vx. st ,y st ,z st and target voxel Vx t, y t, z t The relative distance is then used to select the voxel Vx based on the comparison of the determined selection weights. j, y j, z j The voxel that follows .

[0024] The processor is also configured to selectively highlight voxels of a 3D surgical path in a display view of a cranial structure on a display to provide visualization of the 3D surgical path. The processor can also be configured such that selectively highlighting voxels of the 3D surgical path in the display view of the cranial structure includes applying a different highlighting to voxels of a portion of the 3D surgical path that is hidden in the display view.

[0025] The processor can be configured such that for each voxel Vx in the series i, y i, z i , the immediately succeeding voxel of voxel Vx i, y i, z i is selected by the processor from a group of adjacent voxels of voxel Vx i, y i, z i that does not include the adjacent voxels of the immediately preceding voxel of voxel Vx i, y i, z i . The selection weights of the adjacent voxels of each voxel Vx i, y i, z i can be determined by the processor, and these selection weights include penalty values based on the relative distance from voxels representing at least a certain threshold density within a predetermined distance. Similarly, for each voxel Vx in the series j, y j, z j , the immediately succeeding voxel of voxel Vx j, y j, z j is selected by the processor from a group of adjacent voxels of voxel Vx j, y j, z j that does not include the adjacent voxels of the immediately preceding voxel of voxel Vx j, y j, z j . The selection weights of the adjacent voxels of each voxel Vx j, y j, z j can be determined by the processor, and these selection weights include penalty values based on the relative distance from voxels representing at least the threshold density within a predetermined distance.

[0026] In one example, the processor is configured such that the threshold density is set to negative five hundred (-500) Hu and the predetermined distance is 0.8 mm. In another example, the processor is configured such that the threshold density is set to bone density.

[0027] The exemplary device may also include a catheter having a distal end and associated catheter position sensing equipment coupled to a processor, and a surgical tool may be operated from the distal end. The position sensing equipment is configured to provide signals such that the processor can track the position of the distal end of the catheter when the catheter is inserted into the subject's skull. In this case, the processor is configured to control a display device to display a corresponding visualization of the catheter's travel, such that a user can use the display view of the 3D surgical path to start from the physical position corresponding to the initial entry voxel Vx e ,y e ,z e of the subject's skull and insert the distal end of the catheter into the subject's skull along the 3D surgical path to deploy the distal end of the catheter to the physical position corresponding to the surgical site target voxel Vx t, ,y t ,z t of the subject's skull.

[0028] The processor may be configured to determine a path starting from the entry voxel Vx e, y e, z e [[ID=2l]]of the subject's skull. In this case, the selection weight of each voxel in the adjacent voxel group of each voxel Vx i, y i, z i of the subject's skull may be determined by the processor on a selected basis that includes the relative proximity to the entry voxel Vx e, y e, z e of the subject's skull and the relative distance to the semi-target voxel Vx st ,y st ,z st of the subject's skull. Similarly, the selection weight of each voxel in the adjacent voxel group of each voxel Vx j, y j, z j of the subject's skull may be determined by the processor on a selected basis that includes the relative proximity to the semi-target voxel Vx st ,y st ,z st of the subject's skull and the relative distance to the target voxel Vx t ,y t ,z t of the subject's skull.

[0029] The processor may also be configured to determine a path starting from the target voxel Vx t ,y t ,z t of the subject's skull. In this case, each voxel Vx i, y i, z iThe selection weight of each voxel in the adjacent voxel group can be determined by the processor on a selected basis, which includes the relative distance from the incoming voxel Vx e, y e, z e and the relative proximity to the semi-target voxel Vx st ,y st ,z st . Similarly, the selection weight of each voxel in the adjacent voxel group of each voxel Vx j, y j, z j can be determined by the processor on a selected basis, which includes the relative distance from the semi-target voxel Vx st ,y st ,z st and the relative proximity to the target voxel Vx t ,y t ,z t . BRIEF DESCRIPTION OF THE DRAWINGS

[0030] A more detailed understanding can be obtained from the following description given by way of example in conjunction with the accompanying drawings.

[0031] Figure 1A is an illustration of voxels of a 3D image obtained from a scan and their adjacent voxels.

[0032] Figure 1B is a graphical representation showing Figure 1A example symbols of corresponding voxels.

[0033] Figure 2 is an illustration of an exemplary system that can implement one or more features of the present disclosure.

[0034] Figure 3 is a graphical depiction of a selected display view showing a surgical path between endpoints derived in a conventional manner.

[0035] Figure 4 is a graphical depiction of a display view corresponding to Figure 3 showing a surgical path between endpoints derived according to the teachings of the present invention.

[0036] Figure 5 is a flowchart of deriving Figure 4 the surgical path between the endpoints shown according to the teachings of the present invention.

[0037] Figure 6A and Figure 6B are graphical descriptions of the relative positions in the first case, which are the immediately preceding voxels( Figure 6A)Relative to the voxel for which subsequent voxels are to be determined ( Figure 6B )The relative position.

[0038] Figure 7A And Figure 7B Are graphical depictions of the relative position in the second case, which is the relative position of the immediately preceding voxel ( Figure 7A )Relative to the voxel for which subsequent voxels are to be determined ( Figure 7B )The relative position.

[0039] Figure 8A And Figure 8B Are graphical depictions of the relative position in the third case, which is the relative position of the immediately preceding voxel ( Figure 8A )Relative to the voxel for which subsequent voxels are to be determined ( Figure 8B )The relative position.

[0040] Figure 9 Is a graphical depiction of the display view corresponding to Figure 3 Of the display view, showing the surgical path between the endpoints derived from another example according to the teachings of the present invention.

[0041] Figure 10 Is a flowchart for deriving the surgical path between the endpoints shown according to the teachings of the present invention Figure 9 Shown. Detailed Description

[0042] According to an embodiment of the disclosed subject matter, imaging data in the form of voxels of a subject's head scan is used to derive visualization and three-dimensional (3D) mapping of a path to a desired location, such as an internal cranial location where surgery is to be performed.

[0043] For reference herein, a voxel can be represented by the symbol Vx,y,z, where z represents a particular slice from a series of imaging slices obtained from the scan, and x and y are coordinates in the z slice. The order of the subscripts x, y, and z in the symbol Vx,y,z is for illustrative purposes and is not intended to be limiting. For example, Vz,y,x can be used as the symbol.

[0044] The voxel Vx,y,z can be considered a cube, which is typically surrounded by 26 other voxels, where the voxel Vx,y,z is located at the center of a 3×3 cube array of voxels, as Figure 1A Shown. Exceptions are where x or y represents a coordinate at the edge of slice z, or where z is the first or last slice of a series of imaging slices.

[0045] The 26 surrounding voxels of the voxel Vx,y,z are referred to herein as "adjacent voxels". It should be recognized that the 26 voxels of the voxel Vx,y,z consist of:

[0046] Six "adjacent" voxels, namely voxels Vx+1,y,z, Vx-1,y,z, Vx,y+1,z, Vx,y-1,z, Vx,y,z-1, and Vx,y,z+1;

[0047] Twelve "2D diagonally adjacent" voxels, namely voxels Vx+1,y+1,z, Vx+1,y-1,z, Vx-1,y+1,z, Vx-1,y-1,z, Vx,y+1,z+1, Vx,y-1,z+1, Vx+1,y,z+1, Vx-1,y,z+1, Vx,y+1,z-1, Vx,y-1,z-1, Vx+1,y,z-1, and Vx-1,y,z-1; and

[0048] Eight "3D diagonally adjacent" voxels, namely voxels Vx+1,y+1,z+1, Vx-1,y+1,z+1, Vx+1,y-1,z+1, Vx-1,y-1,z+1, Vx+1,y+1,z-1, Vx-1,y+1,z-1, Vx+1,y-1,z-1, and Vx-1,y-1,z-1;

[0049] In Figure 1B is shown.

[0050] From an initial entry site starting at voxel Vx e ,y e ,z e to a surgical target site at voxel Vx t ,y t ,z t is defined by a series of voxels, where each voxel between voxel Vx e ,y e ,z e and voxel Vx t ,y t ,z t is an adjacent voxel of both the immediately preceding voxel and the immediately following voxel in the series that defines the path.

[0051] Figure 2 FIG. is an illustration of an exemplary mapping system 20 in which one or more features of the present disclosure may be implemented. The mapping system 20 includes a data processing component 22 and a data storage component 24, which are configured to process and store 3D scan images. For example, based on 3D scan images derived from imaging data scanned from the head 26 of a patient 28, an otolaryngologist (ENT) 30 will perform a non-invasive surgical procedure on a selected site within the patient's head 26.

[0052] The mapping system 20 includes a monitor or other display device 32 for selectively displaying, for example, a selected cross-sectional view or perspective view of a 3D scan image from a patient's head 26. The data processing component 22 may include one or more CPUs, GPUs, and / or other processors coupled to the data storage component 24 and the display device 32 to generate a desired cross-sectional view or perspective view on the display device 32 based on the 3D scan image, which is, for example, derived from scan data of the patient's head 26.

[0053] For a 3D-like perspective view displayed on the display device 32, in the case where the display device employs a Cartesian pixel display, the voxels are appropriately mapped to pixels to provide a perspective view that appears to have three-dimensional space using conventional GPU techniques. However, in the case of using a holographic or other true 3D display device, the voxels can be directly mapped to 3D coordinate display elements.

[0054] The data processing component 22 is further configured to control the display device to control the 3D surgical path between selected voxels in the displayed view by applying a predetermined attribute (such as a solid color) to the display voxels that define a particular 3D surgical path, which is referred to herein as highlighting the voxels of the 3D surgical path.

[0055] If, in a particular view, a portion of the path lies beneath barrier voxels (such as bone or tissue), that portion of the path can be highlighted in a different manner (such as with a different color) to indicate that the path portion is actually hidden behind the barrier material (such as bone or tissue). In such a case, the ENT doctor may wish to select a different view of the 3D scan image in which the previously hidden portion of the path is not behind the barrier material.

[0056] For example, for Figure 9 the view shown, at voxel Vx st ,y st ,z st and voxel Vx t, y t, z t a portion of the determined path shown between them appears to pass through bone material. If the portion of the channel that appears to pass through bone material is actually determined to be in a channel beneath the bone material, the processing component 22 preferably applies a different manner of highlighting such that the displayed view reflects the actual relative position of the path portion beneath the displayed bone material.

[0057] The mapping system 20 includes one or more peripheral devices (such as a trackball and / or touchpad 34) to allow a user to select a particular view of the scanned 3D imaging data of, for example, the head 26, for display on the display device 32. One or more peripheral devices (such as device 34) are also configured to allow the user to select a particular voxel as an endpoint of a path between the devices. Such peripheral devices may include, but are not limited to, a computer mouse device, a video game controller device, a joystick device, a laser pointing device, a voice command device, and a touch screen display controller. Preferably, one or more peripheral devices are employed to allow a user (such as an ENT physician 30 or a surgical assistant) to scan through the continuous views of the 3D scanned image as needed and select a target voxel at which to deploy a surgical tool to perform the surgical procedure.

[0058] The mapping system 20 may also include equipment, such as a catheter 38, which may include surgical tools or through which surgical tools may be inserted so as to be manipulated at the distal end of the catheter 38. The catheter 38 may include an ultrasound transducer configured to obtain biometric data or ultrasound slices, etc. The distal end of the catheter 38 may include a probe that operates in conjunction with a positioning pad 39 disposed on a gurney 41 on which the patient 28 is placed for surgical procedures.

[0059] exist Figure 2 In the example shown, the distal tip probe and localization pad 39 of the catheter 38 include position sensing devices and are coupled to the processing assembly 22 via respective cables 42, 43. In this example, the processing assembly 22 is configured to use the signals from the catheter probe and localization pad 29 to track the position of the distal tip of the catheter 38 as it is inserted into the skull of the subject by the ENT physician 30 and to display a visualization of the catheter's progress on the display device 32 in conjunction with a view of the 3D scan image being displayed.

[0060] In this way, when positioning surgical tools for a surgical procedure, the ENT physician 30 can use the displayed view to follow the path from the voxel Vx to the voxel Vx. e ,y e ,z e The initial entry point starts at voxel Vx t ,y t ,z tSurgery is performed on the 3D surgical path for determining the surgical target site at [location]. Therefore, referring to the views shown, starting from the physical position in the subject's skull corresponding to the initial entry site, the ENT doctor 30 inserts the distal end of the catheter 38 along the path to deploy the distal end of the catheter at the physical position corresponding to the target site by following the path shown. At this time, if a surgical tool has been set at the distal end of the catheter, or the surgical tool can be inserted through the catheter to perform surgery at the target site, the surgical tool is correctly positioned for the surgical procedure.

[0061] As described above, by selecting the initial entry site, voxels, and the surgical target site, voxels Vx t , y t , z t as endpoints, the path for non-invasive craniocerebral surgery is determined. Then, the path is defined by a series of voxels, where each voxel between voxels Vx e , y e , z e and voxels Vx t , y t , z t is an adjacent voxel to both its immediately preceding voxel and its immediately following voxel in the series defining the path.

[0062] Generally, starting from one endpoint voxel and ending when reaching the other endpoint, the next voxel in the path series is determined by selecting the "best" subsequent voxel from 26 adjacent voxels using the so-called A* (A-Star) algorithm.

[0063] The A* algorithm is a well-known algorithm for searching paths in CT scan mapping. The main parameters set in the A* algorithm are in the following equation: F = G + H. The F, G, and H variables are attributed to each voxel and are calculated for each adjacent voxel in combination with the subsequent voxel of the path series for selecting voxels. In the case where an adjacent voxel is a barrier voxel (such as representing bone or tissue), that voxel is automatically excluded from being the next voxel in the series.

[0064] F is the weight of the voxel. G is the distance between the voxel and the starting endpoint voxel. H is the heuristic algorithm, that is, the estimated distance from the voxel to the end point voxel.

[0065] In addition to the F, G, and H parameters, two lists of voxels are maintained in the implementation of the algorithm: the open list and the closed list. The open list is a list containing the optional voxels that have been evaluated, but not all possible subsequent voxels have been evaluated. This is a list of tasks to be processed.

[0066] The closed list is a list that contains the voxels that have already been evaluated, and all possible subsequent voxels have been evaluated and added to the open list if applicable.

[0067] First, add the starting endpoint voxel Vx e , y e , z e to the open list to start the A* algorithm.

[0068] Repeat the following steps:

[0069] a. Select the voxel with the lowest cost (F) in the open list. This is called the current voxel.

[0070] b. Move the current voxel to the closed list.

[0071] c. For each of the 26 voxels of the current voxel:

[0072] i. If the adjacent voxel is not selectable (tissue, bone, or other barrier voxel types), or if the adjacent voxel is in the closed list, ignore it.

[0073] ii. If the adjacent voxel is not in the open list, add the adjacent voxel to the open list. Set the current voxel as the previous voxel of the adjacent voxel and determine and record the F, G, and H costs of the adjacent voxel.

[0074] iii. Using the G cost as a metric, check if the path to the adjacent voxel is better. A lower G cost means it is a better path. If so, change the previous voxel of the neighbor voxel to the current voxel and recalculate the G and F costs of the node. If the open list remains sorted according to the cost F, a change may need to be considered.

[0075] When the target voxel Vx t , y t , z t is added to the closed list, the process stops, in which case the path has been found. Or, when the open list is empty, the process stops, in which case the algorithm fails to find the target voxel Vx t , y t , z t .

[0076] In the case where the target voxel Vx t , y t , z t is found, from the target voxel Vx t , y t , z tWorking backward, a series of voxels from each enclosed list voxel to its previous voxel is saved as a path until the starting voxel Vx is reached. e ,y e ,z e 。

[0077] Since all 26 neighboring voxels are considered to select the next voxel in the series, this process is computationally complex and relatively time - and resource - consuming.

[0078] Figure 3 A display view of the voxel path from the entry - site voxel Vx e ,y e ,z e starting to the surgical - site target voxel Vx t ,y t ,z t using the conventional A* algorithm is shown. The processing unit 22 has highlighted the voxels in the conventionally determined path such that the solid line representing the determined path between the entry - site voxel Vx e ,y e ,z e and the target voxel Vx t ,y t ,z t is shown.

[0079] As Figure 3 shown, the conventionally determined path closely follows the nasal bone. Thus, inserting the catheter 38 along the conventionally determined path increases the difficulty of operating the surgical tool at the target site.

[0080] According to an embodiment of the present invention, the processing component 22 is configured to perform cranial path mapping to define the desired surgical path in a faster and less computationally complex manner, which also provides a better separation from the bone and / or other barrier voxels.

[0081] For example, Figure 4 a display view of the voxel path from the same entry - site voxel Vx e ,y e ,z e starting to Figure 3 the same surgical - site target voxel Vx t ,y t ,z t using the improved A* algorithm is shown. The processing unit 22 has highlighted the voxels in the determined path Figure 4 shown such that the entry - site voxel Vx e ,y e ,z e and the target voxel Vx t ,yt , z t The solid line of the determined path between has been shown.

[0082] In an exemplary embodiment of the present invention that generates Figure 4 the path shown, the equation F = G + H is still employed, and the value of F remains F = G + H. However, the value of G is the sum of the distance from the starting endpoint voxel to the current voxel plus a penalty value, which is a function of the proximity of the voxel to voxels of at least a certain threshold density (such as voxels representing tissue or bone). The value of H is the Euclidean distance from the current voxel to the end voxel.

[0083] As Figure 4 shown, where possible, the exemplary determined path passes through the nasal cavity from the illustrated bone for a considerable distance. Thus, inserting the catheter 38 along the determined path reduces the operating difficulty of the surgical tool at the target site.

[0084] Although preferably starting with the entry site voxel Vx e , y e , z e as the starting endpoint voxel and the target site voxel Vx t , y t , z t as the ending endpoint voxel, the process can be implemented starting with the entry site voxel Vx e , y e , z e as the ending endpoint voxel and the target site voxel Vx t , y t , z t as the starting endpoint voxel.

[0085] An example of the penalty value P added when determining the value of G is given by P, which is equal to the maximum of the value 0.0 mm or (p - d), where p is a predetermined distance from the desired minimum spacing from relatively dense material, and d is the distance between the current voxel and the nearest voxel of a density representing at least a certain threshold density.

[0086] For example, the threshold density can be set to measure the distance to voxels having a Hounsfield value of at least negative five hundred (-500 HU) or greater, which include voxels representing bone, tissue, and other barrier substances. If desired, the threshold can be set to the density of a specific substance, such as the density of bone, tissue, or another type of barrier substance.

[0087] For example, the predetermined distance p can be set to 0.8 mm. In this case, if the current voxel is more than 0.8 mm away from the nearest voxel or relatively dense voxels (i.e., at least one of the threshold densities), no penalty value is added to the common G value. Thus, the penalty value is calculated in 3D space by finding the distance d from the current voxel to any relatively dense voxels in all directions within a sphere of radius p, which is a sphere of radius 0.8 mm in this example.

[0088] To reduce the computational complexity of the mapping method, when implementing the improved A* algorithm, the number of adjacent voxels evaluated relative to the current voxel automatically eliminates the previous voxel of the current voxel and all adjacent voxels that are also adjacent to the previous voxel of the current voxel. In this process, depending on whether the current voxel is adjacent to its previous voxel, on a 2D diagonal, or on a 3D diagonal, the number of voxels that meet the conditions of the voxel group considered to be the subsequent voxels of the current voxel is different.

[0089] In the case where the previous voxel of the current voxel (the solid voxel shown in Figure 6A is adjacent to the current voxel (the solid voxel shown in Figure 6B all the voxels represented by the shading are automatically eliminated from the selection process of the subsequent voxels of the current voxel. Only 9 non-shaded voxels define the potential subsequent voxel group of the current voxel, and these 9 non-shaded voxels are not adjacent to the previous voxel. In the adjacent cases shown in Figure 6A and Figure 6B using the symbols in Figure 1B and the current voxel represented as Vx,y,x, the 9 voxels that define the potential subsequent voxel group of the current voxel are the "adjacent" voxel Vx,y,z+1, the "2D diagonal adjacent" voxels Vx,y+1,z+1, Vx,y-1,z+1, Vx+1,y,z+1, Vx-1,y,z+1, and the "3D diagonal adjacent" voxels Vx+1,y+1,z+1, Vx-1,y+1,z+1, Vx+1,y-1,z+1, Vx-1,y-1,z+1.

[0090] In the case where the previous voxel of the current voxel (the solid voxel shown in Figure 7A is on the 3D diagonal of the current voxel (the solid voxel shown in Figure 7B all the voxels represented by the shading are automatically eliminated from the selection process of the subsequent voxels of the current voxel. Only 19 non-shaded voxels define the potential subsequent voxel group of the current voxel, and these 19 non-shaded voxels are not adjacent to the previous voxel. In the 3D diagonal cases shown in Figure 7A and Figure 7B using the symbols in Figure 1BThe symbol and the current voxel represented as Vx,y,x, the 19 voxels that define the potential subsequent voxel group of the current voxel are the "adjacent" voxels Vx-1,y,z, Vx,y+1,z, and Vx,y,z+1; the "2D diagonal adjacent" voxels Vx+1,y+1,z, Vx-1,y+1,z, Vx-1,y-1,z, Vx,y+1,z+1, Vx,y-1,z+1, Vx+1,y,z+1, Vx-1,y,z+1, Vx,y+1,z-1, and Vx-1,y,z-1; and the "3D diagonal adjacent" voxels Vx+1,y+1,z+1, Vx-1,y+1,z+1, Vx+1,y-1,z+1, Vx-1,y-1,z+1, Vx+1,y+1,z-1, Vx-1,y+1,z-1, and Vx-1,y-1,z-1.

[0091] In the case where the previous voxel of the current voxel (such as the solid voxel shown in Figure 8A is located on the 2D diagonal of the current voxel (such as the solid voxel shown in Figure 8B , all the voxels represented by the shading are automatically eliminated from the selection process of the subsequent voxels of the current voxel. Only 15 non-shaded voxels define the potential subsequent voxel group of the current voxel, and these 15 non-shaded voxels are not adjacent voxels of the previous voxel. In Figure 8A and Figure 8B the 2D diagonal cases shown, using the symbol and the current voxel represented as Vx,y,x in Figure 1B , the 15 voxels that define the potential subsequent voxel group of the current voxel are the "adjacent" voxels Vx,y+1,z and Vx,y,z+1; the "2D diagonally adjacent" voxels Vx+1,y+1,z, Vx-1,y+1,z, Vx,y+1,z+1, Vx,y-1,z+1, Vx+1,y,z+1, Vx-1,y,z+1, and Vx,y+1,z-1; and the "3D diagonal adjacent" voxels Vx+1,y+1,z+1, Vx-1,y+1,z+1, Vx+1,y-1,z+1, Vx-1,y-1,z+1, Vx+1,y+1,z-1, and Vx-1,y+1,z-1.

[0092] For any given voxel, there are 6 choices to reach an adjacent adjacent voxel. For any given voxel, there are 8 choices to reach a 3D diagonal adjacent voxel. For any given voxel, there are 12 choices to reach a 2D diagonal adjacent voxel. Therefore, according to the exemplary inventive method of selecting subsequent voxels, compared with the 26 voxels considered in the traditional method, the average number of voxels considered in the subsequent selection is 14.8, that is, (6*9 + 8*19 + 12*15) / 26 = 14.8).

[0093] Generally, this process is based onFigure 5 is carried out as follows. In step 501, the ENT doctor selects the entry voxel and the target end voxel. In step 502, for each path voxel having a preceding path voxel, the subsequent path voxel is selected from the group of adjacent voxels of the adjacent voxels that does not include the preceding voxel. In step 503, subsequent voxel selection is performed based on the relative proximity to the starting end point and the relative distance to the ending end point, where the voxel proximity to voxels having at least a certain threshold density is penalized. In step 504, the mapped path is displayed to the ENT doctor.

[0094] More specifically, a method for mapping and displaying a three-dimensional (3D) surgical path within a displayed cranial structure imaging is provided, where the cranial structure is obtained from voxels of a cranial scan of a subject. An initial entry voxel Vx e, y e, z e and the surgical site target voxel Vx t, ,y t, z t are selected as the end points of the path. Then, a series of voxels are mapped such that each voxel between the entry voxel Vx e, y e, z e and the target voxel Vx t, y t, z t is an adjacent voxel of both the preceding voxel and the subsequent voxel in the series to define the 3D surgical path. For each voxel Vx i, y i, z i in the series having a preceding voxel, the subsequent voxel of the voxel Vx i, y i, z i is selected from the group of adjacent voxels of the voxel Vx i, y i, z i that does not include the adjacent voxel of the preceding voxel of the voxel Vx i, y i, z i . This selection includes determining the selection weight of each voxel in a set of adjacent voxels on a selected basis, where the selected basis includes the relative distance to the end point voxels and Vx t, y t, z t and the relative distance to voxels representing at least a certain threshold density within a predetermined distance. Then, based on the comparison of the determined selection weights, by selecting the voxel Vx i, y i, z iSelect the immediately subsequent voxel. Then, selectively highlight the voxels of the 3D surgical path in the display view of the skull structure to provide visualization of the 3D surgical path.

[0095] Another embodiment of the present invention includes semi-targeted selection based on the knowledge of ENT doctors about cranial structures. For example, in cases where the path needs to pass through a narrow channel, etc., "semi-target" voxels can be selected according to the knowledge of ENT doctors about where the path must go, and the selection can also consider known cavities. Figure 9 Shows in addition to Figure 3 from the same entry site voxel Vx t ,y t ,z t to the same surgical site target voxel Vx e ,y e ,z e using semi-target voxels Vx st ,y st ,z st The display view of the determined voxel path. The processing unit 22 has highlighted the Figure 9 voxels in the determined path shown, such that the solid line showing the determined path between the entry site voxel Vx st ,y st ,z st and the target voxel Vx e ,y e ,z e and the target voxel Vx t ,y t ,z t is shown.

[0096] In an exemplary embodiment of the present invention that generates the path shown in Figure 9 , compared with the speed of simply directly calculating the path between the entry site voxel Vx e ,y e ,z e and the target voxel Vx t ,y t ,z t using traditional methods, the speed of this process is 6 times faster.

[0097] Specifically, when the voxels representing bone are located between the initial entry voxel Vx e, y e, z e and the surgical site target voxel Vx t, y t, z tThe method is more efficient when within the shortest line (Euclidean distance) between. In this case, it is possible to advantageously select a semi-target voxel Vx e, y e, z e and the surgical site target voxel Vx t, y t, z t such that the voxel representing bone is not within the shortest line between the initial entry voxel Vx st, y st, z st and the semi-target voxel Vx e, y e, z e and the semi-target voxel Vx st, y st, z st between.

[0098] As Figure 9 shown, where possible, the exemplary determined path passes through a significant distance of the nasal cavity from the illustrated bone. Thus, inserting the catheter 38 along the determined path reduces the operational difficulty of the surgical tool at the target site.

[0099] Generally, the process proceeds according to Figure 10 the steps. In step 1001, the ENT doctor selects the entry endpoint voxel and the target endpoint voxel. In step 1002, the ENT doctor selects the semi-target voxel between the endpoint voxels. In step 1003, subsequent voxel selection is performed from one endpoint voxel to the semi-target voxel and then from the semi-target voxel to the other endpoint voxel. In step 1004, the mapped path is displayed to the ENT doctor.

[0100] More specifically, another method for mapping and displaying a three-dimensional (3D) surgical path within the displayed cranial structure imaging is provided, where the cranial structure is obtained from the voxels of a cranial scan of a subject. An initial entry voxel Vx e, y e, z e and the surgical site target voxel Vx t, y t, z t are selected, where the voxel representing bone is within the shortest path between the initial entry voxel Vx e, y e, z e and the surgical site target voxel Vx t, y t, z t between. The initial entry voxel Vx e, y e, z e and the surgical site target voxel Vxt, y t, z t the semi-target voxel Vx between st ,y st ,z st . For a series of voxels including the semi-target voxel Vx st, y st, z st , perform mapping such that each voxel between the entry voxel Vxe,ye,ze and the target voxel Vxt,yt,zt is an adjacent voxel of both the immediately preceding voxel and the immediately following voxel in the series, to define a 3D surgical path.

[0101] For each voxel Vxj,yj,zj in the series between the initial entry voxel Vx e, y e, z e and the semi-target voxel Vx st, y st, z st , select the immediately following voxel of the voxel Vx i, y i, z i from the group of adjacent voxels of the voxel Vx i, y i, z i . This selection includes determining a selection weight for each voxel in the group of adjacent voxels based on the selection, and the basis of the selection includes the relative distances from the entry voxel Vx e, y e, z e and the semi-target voxel Vx st, y st, z st . Select the immediately following voxel of the voxel Vx i, y i, z i based on a comparison of the determined selection weights.

[0102] For each voxel Vx st, y st, z st in the series between the semi-target voxel Vx t, y t, z t and the target voxel Vx j, y j, z j , select the voxel Vx j, y j, z j from the group of adjacent voxels of the voxel Vx j, y j, z jThe selection includes determining a selection weight for each voxel in the group of neighboring voxels based on a selection including the weight of the voxel with respect to the semi-target voxel Vx. st, y st, z st and target voxel Vx t, y t, z t The voxel Vx is selected based on the comparison of the determined selection weights. j, y j, z j The voxel that follows .

[0103] The selected path voxels are selectively highlighted, and the voxels of the 3D surgical path are displayed in the display view of the cranial structure to provide visualization of the 3D surgical path.

[0104] The implementation using half-objectives can be combined with the use of the exemplary modified A* algorithm disclosed above. In this case, for each voxel Vx in the series i, y i, z i , voxel Vx i, y i, z i The voxel immediately following the voxel Vx i, y i, z i The adjacent voxel group is selected, and the adjacent voxel group does not include voxel Vx i, y i, z i The adjacent voxels of the voxel immediately preceding it. Each voxel Vx i, y i, z i The selection weights of the neighboring voxels of include a penalty value based on the relative distance to the voxels representing at least a certain threshold density within a predetermined distance. j, y j, z j , voxel Vx j, y j, z j The voxel immediately following the voxel Vx j, y j, z j The adjacent voxel group is selected, and the adjacent voxel group does not include voxel Vx j, y j, z j The adjacent voxels of the voxel immediately preceding it. Each voxel Vx j, y j, z jThe determination of the selection weights of adjacent voxels includes penalty values based on the relative distances from voxels representing at least the threshold density within a predetermined distance.

[0105] Any of the functions and methods described herein may be implemented in a general-purpose computer, a processor, or a processor core. By way of example, suitable processors include general-purpose processors, dedicated processors, conventional processors, digital signal processors (DSPs), multiple microprocessors, one or more microprocessors associated with a DSP core, controllers, microcontrollers, application specific integrated circuits (ASICs), field programmable gate array (FPGA) circuits, any other type of integrated circuit (IC), and / or state machines. The manufacturing process may be configured by using hardware description language (HDL) instructions for the processing and the results of other intermediate data including a netlist (such instructions being capable of being stored on a computer-readable medium), thereby manufacturing such a processor. The result of such processing may be a maskwork that is then used in a semiconductor manufacturing process to manufacture a processor implementing the features of the present disclosure.

[0106] Any of the functions and methods described herein may be implemented in a computer program, software, or firmware that is incorporated into a non-transitory computer-readable storage medium for execution by a general-purpose computer or a processor. Examples of non-transitory computer-readable storage media include read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media (such as internal hard disks and removable disks), magneto-optical media, and optical media (such as CD-ROM disks and digital versatile disks (DVDs)).

[0107] It should be understood that many variations are possible based on the disclosure herein. While the features and elements have been described above in specific combinations, each feature or element may be used alone without other features and elements, or each feature or element may be used in various combinations with or without other features and elements.

Claims

1. A method for intra-mapping and displaying a three-dimensional (3D) surgical path in a display imaging of a cranial structure obtained from voxels of a cranial scan of a subject, the method comprising: Select the initial entry voxel Vx e ,y e ,z e and the surgical site target voxel Vx t ,y t ,z t ; Select the initial entry voxel Vx e , y e , z e and the surgical site target voxel Vx t , y t , z t and the half-target voxel Vx st , y st , z st ; Mapping a series of voxels including the semi-target voxel Vx st, y st, z st such that each voxel between the entry voxel Vx e, y e, z e and the target voxel Vx t, y t, z t is an adjacent voxel of both the immediately preceding voxel and the immediately following voxel in the series to define the 3D surgical path; For each voxel Vx in the series between the initial entry voxel Vx e, y e, z e and the semi-target voxel Vx st ,y st ,z st , excluding the voxel Vx i, y i, z i from the immediately preceding voxel, select the voxel Vx i, y i, z i from the adjacent voxel group of the immediately preceding voxel's adjacent voxels, including: i, y i, z i select the immediately succeeding voxel of the voxel Vx i, y i, z i as follows: Determine a selection weight for each voxel in the adjacent voxel group on the basis of the selection, the basis of the selection including a relative distance with respect to the incoming voxel Vx e, y e, z e and the semi-target voxel Vx st ,y st ,z st and a penalty value based on a relative distance with respect to a voxel representing at least a certain threshold density within a predetermined distance; and Select the voxel Vx based on a comparison of the determined selection weights i, y i, z i the immediately subsequent voxel; For each voxel Vx in the series between the semi-target voxel Vx st ,y st ,z st and the target voxel Vx t ,y t ,z t , excluding the voxel Vx j, y j, z j and never including the voxel Vx j, y j, z j adjacent to the immediately preceding voxel, select the voxel Vx j, y j, z j from the group of adjacent voxels of the immediately succeeding voxel of the voxel Vx j, y j, z j , including: Determine a selection weight for each voxel in the adjacent voxel group on a selected basis, the selected basis including a relative distance with respect to the semi-target voxel Vx st ,y st ,z st and the target voxel Vx t ,y t ,z t and a penalty value based on a relative distance with respect to voxels representing at least the threshold density within the predetermined distance; and Select the voxel Vx based on a comparison of the determined selection weights j, y j, z j the immediately succeeding voxel; and Selectively highlighting the voxels of the 3D surgical path in the display view of the cranial structure to provide visualization of the 3D surgical path.

2. According to the method of claim 1, when the voxel representing the bone is within the shortest line between the initial entry voxel Vx e, y e, z e and the target voxel Vx t, y t, z t of the surgical site, where the selection of the semi-target voxel Vx e, y e, z e between the initial entry voxel Vx t, y t, z t and the target voxel Vx st ,y st ,z st of the surgical site is made such that the voxel representing the bone is not within the shortest line between the initial entry voxel Vx e, y e, z e and the semi-target voxel Vx st ,y st ,z st .

3. The method according to any one of claims 1-2, wherein: The threshold density is set to negative five hundred (-500) Hu; and The predetermined distance is 0.8 mm.

4. The method according to any one of claims 1-2, wherein, Selectively highlighting the voxels of the 3D surgical path in the display view of the cranial structure includes applying a different highlighting to the voxels of the portion of the 3D surgical path hidden in the display view.

5. The method according to any one of claims 1-2, wherein: Starting from the incoming voxel Vx e, y e, z e begin to determine the path; Determining each voxel Vx on a selected basis i, y i, z i The selection weight of each voxel in the adjacent voxel group of the voxel Vx e, y e, z e includes the relative proximity to the incoming voxel Vx st ,y st ,z st and the relative distance to the semi-target voxel Vx Determining each voxel Vx on a selected basis j, y j, z j The selection weight of each voxel in the adjacent voxel group of the semi-target voxel Vx st ,y st ,z st includes the relative proximity to the semi-target voxel Vx t ,y t ,z t and the relative distance to the target voxel Vx 6. The method according to any one of claims 1-2, wherein, Starting from the target voxel Vx t, y t, z t begin to determine the path; Determining each voxel Vx on a selected basis i, y i, z i The selection weight of each voxel in the adjacent voxel group of the entering voxel Vx e, y e, z e includes the relative distance to the entering voxel Vx st ,y st ,z st and the relative proximity to the semi-target voxel Vx And Determining each voxel Vx on a selected basis j, y j, z j The selection weight of each voxel in the adjacent voxel group of the semi-target voxel Vx st ,y st ,z st includes the relative distance to the semi-target voxel Vx t ,y t ,z t and the relative proximity to the target voxel Vx 7. An apparatus for intra-mapping and displaying a three-dimensional (3D) surgical path in a display imaging of a cranial structure obtained from voxels of a cranial scan of a subject, the apparatus comprising: A data storage device for storing voxels of a cranial scan of a subject; A processor and an associated display configured to provide cross-sectional and 3D imaging of the cranial structure of the subject based on the cranial scan; Voxel selection device configured for a user to select an initial entry voxel Vx e , y e , z e and a surgical site target voxel Vx t , y t , z t , and configured for a user to select the initial entry voxel Vx e , y e , z e and the surgical site target voxel Vx t , y t , z t and semi-target voxels Vx between them st , y st , z st ; The processor is configured to map a series of voxels including the semi-target voxel Vx st ,y st ,z st such that each voxel between the entry voxel Vx e, y e, z e and the target voxel Vx t, y t, z t is an adjacent voxel of both the immediately preceding voxel and the immediately following voxel in the series to define the 3D surgical path; For each voxel Vx in the series between the entry voxel Vx e, y e, z e and the semi-target voxel Vx st ,y st ,z st , the processor is configured to select the voxel Vx i, y i, z i of the immediately succeeding voxel from the group of adjacent voxels of the immediately preceding voxel that does not include the voxel Vx i, y i, z i : i, y i, z i The adjacent voxel group of the voxel Vx i, y i, z i of the immediately succeeding voxel: Determine a selection weight for each voxel in the adjacent voxel group on a selected basis, the selected basis including a relative distance with respect to the incoming voxel Vx e, y e, z e and the semi-target voxel Vx st ,y st ,z st and a penalty value based on a relative distance with respect to voxels representing at least a certain threshold density within a predetermined distance; And Select the voxel Vx based on a comparison of the determined selection weights i, y i, z i the immediately succeeding voxel; For each voxel Vx in the series between the semi-target voxel Vx st , y st , z st and the target voxel Vx t, y t, z t , the processor is configured to select the voxel Vx j, , y j, , z j of the immediately succeeding voxel from the group of adjacent voxels of the immediately preceding voxel that does not include the voxel Vx j, y j, z j as follows: j, , y j, , z j of the adjacent voxels of the voxel Vx j, , y j, , z j of the immediately succeeding voxel: Determine a selection weight for each voxel in the adjacent voxel group on the basis of the selection, the basis of the selection including a relative distance with respect to the semi-target voxel Vx st ,y st ,z st and the target voxel Vx t ,y t ,z t and a penalty value based on a relative distance with respect to a voxel representing at least the threshold density within the predetermined distance; And Select the voxel Vx based on a comparison of the determined selection weights j, y j, z j the immediately subsequent voxel And The processor is configured to selectively highlight the voxels of the 3D surgical path in the display view of the cranial structure on the display to provide visualization of the 3D surgical path.

8. The apparatus according to claim 7, wherein The processor is configured to set the threshold density to negative five hundred (-500) Hu and the predetermined distance to 0.8 mm.

9. The device according to claim 7, wherein The processor is configured to set the threshold density to bone density.

10. The apparatus according to any one of claims 7-9, further comprising A catheter having a distal end through which a surgical tool can be operated; An associated catheter position sensing device coupled to the processor; The position sensing device is configured to provide a signal such that the processor can track the position of the distal end of the catheter when the catheter is inserted into the skull of the subject; and The processor is configured to control a display device to display a corresponding visualization of the catheter's travel such that a user can use the display view of the 3D surgical path to start from the physical location corresponding to the initial entry voxel Vx e , y e , z e in the subject's skull and insert the distal end of the catheter along the 3D surgical path into the subject's skull to deploy the distal end of the catheter to the physical location corresponding to the target voxel Vx t , y t , z t of the surgical site.

11. The device according to any one of claims 7-9, wherein, The processor is configured to selectively highlight the voxels of the 3D surgical path in the display view of the cranial structure includes applying a different highlighting to the voxels of the portion of the 3D surgical path hidden in the display view.

12. The device according to any one of claims 7-9, wherein The processor is configured to: Starting from the incoming voxel Vx e, y e, z e begin to determine the path; Each voxel Vx i, y i, z i in the group of adjacent voxels is determined by the processor on a selected basis, the selected basis including the relative proximity to the incoming voxel Vx e, y e, z e and the relative distance to the semi-target voxel Vx st ,y st ,z st ; and Each voxel Vx j, y j, z j The selection weight of each voxel in the adjacent voxel group is determined by the processor on a selected basis, and the selected basis includes the relative proximity to the semi-target voxel Vx st ,y st ,z st and the relative distance to the target voxel Vx t ,y t ,z t .

13. The device according to any one of claims 7-9, wherein, The processor is configured to: Starting from the target voxel Vx t, y t, z t start to determine the path; Each voxel Vx i, y i, z i in the group of adjacent voxels is determined by the processor on a selected basis, the selected basis including the relative distance from the incoming voxel Vx e, y e, z e and the relative proximity to the semi-target voxel Vx st ,y st ,z st ; And Each voxel Vx j, y j, z j The selection weight of each voxel in the adjacent voxel group is determined by the processor on a selected basis, the selected basis including the relative distance from the semi-target voxel Vx st ,y st ,z st and the relative proximity to the target voxel Vx t ,y t ,z t .

Images