(19)
(11)EP 3 106 117 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
25.03.2020 Bulletin 2020/13

(21)Application number: 16175122.7

(22)Date of filing:  17.06.2016
(51)Int. Cl.: 
A61B 34/10  (2016.01)
G06T 19/00  (2011.01)

(54)

SYSTEMS AND METHODS FOR NAVIGATING THROUGH AIRWAYS IN A VIRTUAL BRONCHOSCOPY VIEW

SYSTEME UND VERFAHREN ZUR NAVIGATION DURCH LUFTWEGE IN EINER VIRTUELLEN BRONCHOSKOPIEANSICHT

SYSTÈMES ET PROCÉDÉS POUR NAVIGUER À TRAVERS DES VOIES RESPIRATOIRES DANS UNE VUE DE BRONCHOSCOPIE VIRTUELLE


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 19.06.2015 US 201562181824 P
16.06.2016 US 201615184057

(43)Date of publication of application:
21.12.2016 Bulletin 2016/51

(73)Proprietor: Covidien LP
Mansfield, MA 02048 (US)

(72)Inventors:
  • MERKINE, Rahaf
    3461616 Haifa (IL)
  • AVERBUCH, Dorian
    4732157 Ramat Hasharon (IL)
  • LACHMANOVICH, Elad D.
    7176682 Modin (IL)

(74)Representative: Maschio, Antonio et al
Maschio & Soames IP Limited 30 Carlton Crescent
Southampton SO15 2EW
Southampton SO15 2EW (GB)


(56)References cited: : 
EP-A2- 0 919 956
US-A1- 2007 052 724
US-A1- 2011 018 871
US-A1- 2003 152 897
US-A1- 2008 118 117
US-A1- 2012 136 208
  
  • LIN H ET AL: "Slice-based virtual endoscopy navigation", IEEE CONFERENCE ON INFORMATION VISUALIZATION. INTERNATIONALCONFERENCE ON COMPUTER VISUALIZATION AND GRAPHICS, XX, XX, 1 January 2001 (2001-01-01), pages 711-716, XP008080951,
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

BACKGROUND


Technical Field



[0001] The present disclosure relates to systems and methods for displaying medical images in a dynamic and changing manner. More particularly, the present disclosure relates to systems and methods for dynamically displaying medical images during forward and backward movement in a virtual bronchoscopy during pathway planning based on a position and a direction of a virtual camera being navigated through airways of the lungs.

Discussion of Related Art



[0002] Pathway planning visualization techniques are rapidly growing in various medical areas. Visualization techniques help minimize the size of an incision, non-invasively treat diseases of a patient in surgeries, and non-invasively navigate inside of patients to identify and treat target lesions. However, visualization may pose unexpected risks when incorrect information is displayed. For example, when navigating a virtual camera view in a backward or retracting direction through an airway of the lungs, the views provided to a clinician may make it difficult for the clinician to retrace the previously taken steps and return to a previous location. Moreover, a user may find the virtual camera view navigating outside of the airways of the lungs.

[0003] Document US2007052724 A1 describes a method of navigating along a biological object with a lumen represented by a three-dimensional volume data set comprises generating a plurality of navigation segments connectable in a sequence, each segment having a start point within the lumen, a direction and a length. The navigation may be used for a camera in a virtual endoscopic examination, for example. The direction of each segment is determined by casting groups of rays outwards from the start point of the segment to the object wall, and calculating an average ray length for each group. The group having the largest average ray length is selected, and the axial direction of this group is used as the direction for the segment. The average ray lengths of the groups may be weighted using the direction of the previous segments to bias the navigation generally forward, or may be weighted using a view direction of the camera to allow a user to turn the camera into a chosen branch in the object. The method comprises interpolating between the current navigation direction and the navigation direction a few segments ahead and using the result as a new viewing direction for the camera in order to avoid sudden sharp rotations of the camera if a straight region of lumen is followed by a sharp turn.

SUMMARY



[0004] The invention is defined in the appended claims.

[0005] As described herein is a method for displaying virtual bronchoscopy views while navigating through an airway of a virtual bronchoscopy. The method includes determining a first location and a first direction at the first location, storing the first location and the first

[0006] direction in memory, displaying a first virtual camera view corresponding to the first location, determining a second location corresponding to movement through the airway of the virtual bronchoscopy, storing the second location in the memory, displaying a second virtual camera view corresponding to the second location, determining a second direction based on the first location and the second location, storing the second direction in the memory, determining a third location corresponding to further movement through the virtual bronchoscopy, and determining whether the further movement is in a forward direction or a backward direction.

[0007] If it is determined that the further movement is in the forward direction, the method includes displaying a third virtual camera view corresponding to the third location. And If it is determined that movement is in the backward direction, the method includes retrieving the stored first direction and the stored second direction from the memory, determining a smoothing vector based on the stored first direction and the stored second direction, obtaining a smoothed virtual camera view based on the smoothing vector, and displaying the smoothed virtual camera view.

[0008] As described herein, determining whether the further movement is in a forward direction or a backward direction includes determining a next pointer location and a current pointer location on a virtual bronchoscopy screen, calculating the difference between a coordinate of the next pointer location and a coordinate of the next pointer location. If the calculated difference is positive, determining that the further movement is in the backward direction. And if the calculated difference is negative, determining that the further movement is in the forward direction.

[0009] As described herein, the first location, the second location, and the third location are determined based on the location of a pointer or cursor on a screen which is displaying the virtual camera views. In yet another embodiment, the method further includes that if it is determined that the further movement is in the forward direction determining a third direction based on the second location and the third location, and storing the third direction in the memory.

[0010] As described herein, determining the smoothing vector includes determining a first vector based on the first location and first direction, determining a second vector based on the first location and the second direction, and averaging the first vector and the second vector to obtain the smoothing vector.

[0011] As described herein, the spline is a spline of order two or a spline of order four. In embodiments, the method further includes receiving an input from a user which alters the first, second, third, or smoothed virtual camera views, and storing the altered first, second, third, or smoothed virtual camera view. In a further embodiment, determining the smoothing vector includes determining a vector having a direction between the first direction and the second direction.

[0012] As described herein is an apparatus for displaying virtual bronchoscopy views while navigating through an airway of a virtual bronchoscopy. The apparatus includes a network interface configured to receive position information of a navigation instrument from at least one position sensor of the navigation instrument, the position information including physical locations, a memory storing a plurality of virtual camera views of the virtual bronchoscopy, instructions, a first location, a first direction at the first location, a second location, and a second direction at the second location, a processor configured to execute the instructions. The instructions, when executed by the processor, cause the processor to

[0013] determine whether movement through the airway of the virtual bronchoscopy is in a forward direction or a backward direction. If it is determined that the movement is in the forward direction, the instructions further cause the processor to determine a third location corresponding to the movement through the airway of the virtual bronchoscopy, and determine a third direction based on the second location and the third location. If it is determined that movement is in the backward direction, the instructions further cause the processor to retrieve the first direction and the second direction from the memory, and determine a smoothing vector based on the first direction and the second direction. The apparatus further includes a display configured to dynamically display, on a screen, images of a smoothed virtual camera view corresponding to the determined smoothing vector.

BRIEF DESCRIPTION OF THE DRAWINGS



[0014] Objects and features of the presently disclosed systems and methods will become apparent to those of ordinary skill in the art when descriptions of various embodiments are read with reference to the accompanying drawings, of which:

FIG. 1 is a schematic diagram of a computing device for pathway planning in accordance with an embodiment of the present disclosure;

FIG. 2 is a diagram illustrating the four phases of pathway planning in accordance with the present disclosure;

FIG. 3 is a flowchart illustrating a method for dynamically determining and displaying virtual camera views for forward and backward motion within lung airways according to an embodiment of the present invention;

FIG. 4 is a flowchart illustrating a method of determining forward or backward direction within lung airways according to an embodiment of the present disclosure;

FIGS. 5 and 6A-6C are graphical illustrations of views while navigating within lung airways in accordance with an embodiment of the present disclosure; and

FIG. 7 is a graphical illustration of steps taken to navigate through lung airways in accordance with some embodiments of the present disclosure.


DETAILED DESCRIPTION



[0015] The Virtual Bronchoscopy (VB) view enables a user to interact with a virtual camera (or point of view of the user) and to modify both the location and direction of the virtual camera view inside the airways of lungs. The movement backwards in the VB view could be achieved by adjusting the virtual camera (or user point of view) on one of the planar views (Axial, Coronal, Sagittal) and then going backwards in a straight line in the VB view. However, this method may involve at least two views and it may be difficult to retrace the actual steps and return to a previous location. Also, a user may find the virtual camera navigating outside the airways.

[0016] As described herein, the movement forward, including turns, is recorded by storing each individual step in a stack and when the virtual camera moves backwards, its backward step is taken from the stack, therefore retaining both the actual location and direction of the virtual camera. Movement forward is performed by moving in straight lines. Movement sideways is performed by operating a data input device such as a mouse pointer at a position on the VB view and the center of the VB view updates to that position by way of animation to allow for a better user experience.

[0017] When the virtual camera view is turned (to the right or to the left) while moving forward in response to movement of a cursor or pointer on the screen and/or selection of a button by a user operating a user input device such as a mouse or touchpad, the turn takes place after a movement in a straight line is performed. The software saves a step or several steps forward in the stack and then a step with the turn. The step of the turn is performed in a single animation to provide a smooth turn. The animation is calculated based on the virtual camera's current location, current direction, the new rotation axis, and the delta in the 2D's x-axis of the view, i.e., changes in the left or right direction.

[0018] To provide a similar user experience when moving in a backward direction, the systems and methods according to the present disclosure record the location of the cursor or pointer on the display device after the cursor or pointer has been moved by a user via operation of a data input device such as a mouse, a touchpad, a trackball, or a touchscreen. As discussed herein, the x-coordinates and the y-coordinates of the location of the cursor or pointer on the display device is stored in a stack and used to determine forward and backward movement of the virtual camera. When the virtual camera moves backward, the current location and direction at the current location, along with the previous location and direction is taken from a stack. During or before backward movement, an average direction vector or other smoothing vector optimized for backward navigation is calculated for two adjacent steps (e.g., steps i and i-1) in the stack. In some embodiments, the smoothing vector is based on a spline or a Lanczos algorithm being applied to the first vector and the second vector. In the backward movement, the virtual camera view corresponding to the calculated average direction vector or other smoothing vector is used. This allows for smoother animation when performing turns while moving backward.

[0019] Referring now to FIG. 1, the present approach is generally directed to a pathway planning system 10 and method for planning a pathway through an anatomical luminal network of a patient for use during an operation. The pathway planning system 10 may include a computing device 100 such as, for example, a laptop, desktop, tablet, or other similar device, having a display 102, memory 104, one or more processors 106, and/or other components of the type typically found in a computing device. Display 102 may be touch sensitive and/or voice activated, enabling display 102 to serve as both an input and output device. Alternatively, a keyboard 113, mouse 114, or other data input device may be employed.

[0020] Memory 104 includes any non-transitory, computer-readable storage media for storing data and/or software that is executable by processor 106 and which controls the operation of the computing device 100. As described herein, the memory 104 may include one or more solid-state storage devices such as flash memory chips. Alternatively, the memory 104 may be mass storage device connected to the processor 106 through a mass storage controller (not shown) and a communications bus (not shown).

[0021] Although the description of computer-readable media contained herein refers to solid-state storage, it should be appreciated by those skilled in the art that computer-readable storage media can be any available media that can be accessed by the processor 106. That is, computer-readable storage media includes non-transitory, volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer-readable instructions, data structures, program modules or other data. For example, computer-readable storage media includes RAM, ROM, EPROM, EEPROM, flash memory or other solid state memory technology, CD-ROM, DVD, or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by the computing device 100.

[0022] Computing device 100 may also include a network module 108 connected to a distributed network or the internet via a wired or wireless connection for the transmission and reception of data to and from other sources. For example, computing device 100 may receive computed tomographic (CT) images of a patient from a server, for example, a hospital server, an internet server, or other similar servers, for use during pathway planning. Patient CT images may also be provided to computing device 100 via a memory 104, which may be a removable memory.

[0023] A pathway planning module 200 includes a software program stored in memory 104 and executed by processor 106 of the computing device 100. As will be described in more detail below, pathway planning module 200 guides a clinician through a series of steps to develop a pathway plan for later use during a medical procedure. Pathway planning module 200 communicates with user interface module 202 for displaying visual interactive features to a clinician on the display 102 and for receiving clinician input.

[0024] As used herein, the term "clinician" refers to any medical professional (i.e., doctor, surgeon, nurse, or the like) or other user of the pathway planning system 10 involved in planning, performing, monitoring, and/or supervising a medical procedure involving the use of the embodiments of the systems, methods, and apparatuses described herein.

[0025] Referring now to FIG. 2, pathway planning using the pathway planning module 200 may be performed in four separate phases. In a first phase S1, a clinician selects a patient for pathway planning. In a second phase S2, the clinician adds a target. In a third phase S3, the clinician creates the pathway to the target. Finally, in the fourth phase S4, the clinician reviews and accepts the plan and may export the plan for use in a medical procedure. The clinician may repeat either or both of the second and third phases S2 and S3 as needed to select additional targets and/or create additional pathways for a particular patient. For example, the clinician may select additional targets and may create a pathway to each target. The clinician may also or alternatively create multiple pathways to the same target. Once a pathway plan is generated, a virtual bronchoscopy view (illustrated in FIGS. 6A-6C) may be displayed, which allows a clinician to navigate within the virtual airways of the patient based on the pathway plan.

[0026] FIG. 3 is a flowchart illustrating a method 300 for dynamically displaying virtual bronchoscopy views based on position and direction information of a virtual camera in accordance with embodiments of the present invention. At steps 305-310, a location pointed to by data input device 112 on display 102 within the virtual bronchoscopy view is displayed. In some embodiments, the location is set in a known airway such as the trachea or an entry point of the patient. The location pointed to by data input device 112 on display 102 is obtained as 2D x-coordinates and y-coordinates. The virtual location is utilized in order to generate a virtual camera view at the virtual location, at step 315. As the clinician progresses through the airways of the patient in the virtual bronchoscopy view, the clinician clicks or selects various locations within the airways to move forwards and backwards.

[0027] As the virtual location pointed to by data input device 112 (such as by using a pointer or cursor) on display 102 arrives at location Li at step 310 (as further described below with respect to FIG. 7) the view direction Di is utilized. Based on the location Li, one or more processors 106 determine a view direction Di which corresponds to the location Li. Location Li is a 2D coordinate having an x-coordinate and a y-coordinate, with respect to a position on display 102 of the airways.

[0028] View direction Di may be expressed as a vector ṽi having a magnitude and an angle Θi. Angle Θi may be defined as the difference between the angle of the current vector ṽi and the angle of the previous vector ṽi-1, as illustrated in FIG. 7. For example, for a first vector ṽ1 extending from a first location L1 to a second location L2 and a second vector ṽ2 extending from the second location L2 in a direction orthogonal to the first vector ṽi, angle Θ2 of the second vector ṽ2 is 90°.

[0029] Once the location Li and view direction Di are determined, the one or more processors 106 obtain a virtual camera view Ci from memory 104 based on the location Li and view direction Di, at step 315. Virtual camera view Ci is a 2D virtual image to be displayed in the virtual bronchoscopy window 600 (shown in FIGS. 6A, 6B, and 6C). Virtual camera view Ci is a view inside the airways from the perspective of the tip of a virtual camera. Examples of the virtual camera view Ci are shown in FIGS. 6A-6C.

[0030] At step 320, one or more processors 106 store the first location Li and view direction Di in memory 104, for example, within a stack or a lookup table at step Si. An example of a lookup table (LUT) is shown below.
Table 1
Step SiLocation LiView Direction Di
i-1 xi-1, yi-1 Θi-1
i xi, yi Θi
i+1 xi+1, yi+1 Θi+1
i+2 xi+2, yi+2 Θi+2
i+3 xi+3, yi+3 Θi+3
N xn, yn Θn


[0031] As used herein, the term location refers to the coordinate values and data which indicates the location of the pointer or cursor on display 102. View direction refers to the angle difference between the view in a straight line from the current location (a first vector) and the view in a straight line from the previous location (a second vector), as further illustrated in FIG. 7.

[0032] At step 325, virtual camera view Ci is displayed on display 102 in the virtual bronchoscopy window 600, as shown in FIGS. 6A-6C. In some embodiments, a user may, by clicking a button on mouse 114 or depressing a key or a combination of keys on keyboard 113, alter and update the virtual camera view Ci. For example, the user may change the direction thereby displaying a new virtual camera view at a different view direction.

Forward Movement



[0033] Steps 330-355 of FIG. 3 illustrate movement of a virtual camera in a forward direction through the airways. At step 330, the next location Li+1 and the next view direction Di+1 of the virtual camera are obtained based on the location of the pointer or cursor on display 102. The next view direction Di+1 may be determined by determining the direction of the vector extending from location Li to the next location Li+1. At step 335, a determination is made as to whether the virtual camera has moved from location Li to next location Li+1 in a forward direction, as described below with reference to FIG. 4.

[0034] If it is determined that the virtual camera is moving in a forward direction from location Li to next location Li+1, the method proceeds to step 340. At step 340, once both the next location Li+1 and view direction Di+1 are determined, the one or more processors 106 obtains a next virtual camera view Ci+1 from memory 104 based on the next location Li+1 and next view direction Di+1.

[0035] At step 345, one or more processors 106 store the next location Li+1 and next view direction Di+1 in memory 104 at the next step Si+1. At step 350, the next virtual camera view Ci+1 is displayed on display 102 in the virtual bronchoscopy window 600. At step 355, one or more processors 106 set the current location Li+1 at next step Si+1 to current step Si, prior to returning to step 330 to determine next location Li+1.

Backward Movement



[0036] As described herein, if, at step 335, it is determined that the virtual camera is not moving in a forward direction, the method proceeds to step 360. At step 360, it is determined whether the virtual camera is moving in a backward direction. Step 360 is used to confirm that the virtual camera is moving in a backward direction. Movement in a backward direction may be defined as movement to or near a previously-visited position. If, at step 360, it is determined that the movement is not in a backward direction, the method returns back to step 335 to determine whether movement of the virtual camera is in a forward direction.

[0037] If, at step 360, it is determined that movement is in a backward direction, the method proceeds to step 370. Based on the next location Li+1, which is in a backward direction, the one or more processors 106 access a lookup table in memory 104 to determine the previous stored steps in the lookup table which corresponds to next location Li+1. For example, if, at next location Li+1, the coordinates are xi+1, yi+1, the processor would access the lookup table illustrated in Table 1 above and determine that previous locations Li and Li-1 correspond to steps Si and Si-1., respectively. Once steps Si and Si-1 are determined, one or more processors 106, at step 370, obtain the view direction Di at step Si and the view direction Di-1 at step Si-1 from Table 1. Thus, for example, if it is determined that movement of the virtual camera is in a backward direction and the location corresponds to step S5, one or more processors 106 obtain the view direction D4 and the view direction D3 from the lookup table illustrated in Table 1.

[0038] At step 375, one or more processors 106 calculate a smoothing vector V based on view direction Di-1 and view direction Di. As shown in Table 1 above, view directions Di-1 and Di correspond to vector angles Θi-1 and Θi, respectively. In some embodiments, the smoothing vector is a new vector having an angle ΘNi+1, which bisects vector angles Θi-1 and Θi. Thus, for backward motion, by applying smoothing vector to angle Θi of view direction Di, a new view direction at location Li+1 is created with a new angle equal to Θi/2.

[0039] In embodiments, the smoothing vector V is a vector that is based on (1) a first or previous vector defined by location Li-1 and direction Di-1, and (2) a second or current vector defined by location Li and direction Di, and optimized for backward navigation so that, for example, the camera view does not leave the airway and/or the animation of the camera view appears smooth. The smoothing vector V may be a vector between the first and second vectors such as a vector that is the average or weighted average of the first and second vectors. The smoothing vector V may alternatively be determined by using a smoothing algorithm such as a spline or a Lanczos algorithm. The spline may be a quadratic spline (a spline of degree two) or a cubic spline (a spline of degree four).

[0040] After determining a new view direction DNi+1 at location Li+1 based on the smoothing vector, the one or more processors 106 determine, at step 380, a new virtual camera view CNi+1 at location Li+1. In some embodiments, location Li+1 may be location Li-1 or a location near location Li-1. Thus, instead of using the original virtual camera view Ci+1 at location Li+1, one or more processors 106 obtain the original virtual camera view Ci+1 from memory 104 and alter virtual camera view Ci+1 by the new view direction Di+1 using the smoothing vector and generates new virtual camera view CNi+1. At step 385, new virtual camera view CNi+1 is displayed on display 102 in the virtual bronchoscopy window. Following step 385, one or more processors 106 set current location Li+1 for step Si+1 to step Si, at step 390, prior to returning to step 330 to determine next location Li+1.

[0041] Turning now to FIG. 4, a flowchart illustrating a method 400 for the determination of forward and backward motion of steps 335 and 360 of FIG. 3 is described in greater detail. Using the current location Li and previous location Li-1 of the pointer or cursor on display 102, a determination can be made of which directions, forwards or backwards, the virtual camera is moving at the current location Li.

[0042] At step 405, one or more processors 106 obtain the 2D x-coordinates and y-coordinates of current location Li of the pointer on display 102. Next, at step 410, one or more processors 106 obtain the 2D x-coordinates and y-coordinates of next virtual location Li+1 (which is moved from location Li by a user's operation of data input device 112) on display 102.

[0043] At step 415, one or more processors 106 determine whether the difference between the y-coordinate value of next location Li+1 and the y-coordinate value of location Li of the pointer on display 102 is less than zero. If, at step 415, it is determined that the difference between the y-coordinate value of next location Li+1 and the y-coordinate value of location Li is less than zero, then one or more processors 106 determine that the virtual camera is moving in a forward direction.

[0044] If, at step 415, it is determined that the difference between the y-coordinate value of location Li+1 and the y-coordinate value of location Li of the pointer on display 102 is not less than zero, method 400 proceeds to step 420 where it is determined whether the difference between the y-coordinate value of next location Li+1 and the y-coordinate value of location Li is greater than zero. If, at step 415, it is determined that the difference between the y-coordinate value of next location Li+1 and the y-coordinate value of location Li is greater than zero, then one or more processors 106 determine that the virtual camera is moving in a backward direction.

[0045] Referring now to FIGS. 5 and 6A-6C, 3D map window 500 for a virtual bronchoscopy is displayed. When a target is identified and a pathway is identified by the computing device 100, a clinician may want to review the pathway in a navigation review mode. FIG. 5 illustrates the navigation review mode of the planning phase, in which computing device 100 shows a 3D map window 500 and a virtual bronchoscopy window 600 (FIG. 6A-6C) on the screen of display 102 in accordance with embodiments of the present disclosure.

[0046] The 3D map window 500 shows the 3D map and the virtual bronchoscopy window 600 shows virtual bronchoscopic video images. The 3D map window 500 displays and overlays a pathway 505 to a target 550 and a current position indicator 507. In the navigation review mode, the display 102 shows the virtual bronchoscopy window 600 as a fly-through view from the trachea to the target 550.

[0047] The virtual bronchoscopy window 600 also shows a pathway 660 toward the target 550 for review. The current position indicator 507 moves in the 3D map window 500 based on and in accordance with the current position shown in the virtual bronchoscopy window 600. In an aspect, the pathway 660 or 505 may not be displayed based on a display option that a clinician may set between showing the pathway and not showing the pathway.

[0048] The virtual bronchoscopy window 600 includes a slider 670 for opacity. By moving the slider 670, opacity of the virtual bronchoscopic video images may be changing from opaque to transparent. However, an opacity status of the virtual bronchoscopy is not synchronized with the 3D map shown in the 3D map window 500.

[0049] As shown in FIG. 5, airway passage 501 contains three camera views at three respective locations 510, 520, and 530. As the virtual camera navigates to target 550 at each of locations 510, 520, and 530, view directions 510a, 520a, and 530a, respectively, are displayed within virtual bronchoscopy window 600. Each view direction 510a, 520a, and 530a corresponds to the virtual bronchoscopic video images shown in FIGS. 6A, 6B, and 6C, respectively. As the virtual camera progresses from location 510 to 530, the view seen by a user is altered as shown in FIGS. 6A to 6C, respectively.

[0050] In FIG. 6A, a user is able to see, in virtual bronchoscopy window 600, pathway 660 containing locations 510, 520, and 530 along with the forking branches of airway passage 501. As the virtual camera approaches location 520 (FIG. 6B), the view shown in virtual bronchoscopy window 600 is approaching the forking branches. Once the virtual camera has reached location 530 (FIG. 6C), an airway passage is displayed at location 530. During forward motion, a user moves the pointer or cursor with an input device such as a mouse, keyboard, or touchpad, and selects locations forward along pathway 660, such as locations 510, 520, and 530. Thus, as a user notices forking branches, a user is able to select locations along pathway 660 which enter the forking branches, such as location 530. As each location is selected during forward motion, the virtual camera centers the view at that location. During backward motion, as the user moves the pointer or cursor and selects locations backward along pathway 660, the systems and methods of the present disclosure alter and smooth the view at the backward location, as opposed to displaying a virtual camera view centered at the backward location, thereby providing the user with a camera view which prevents the view the user sees in virtual bronchoscopy window 600 from being outside of the airway, For example, the systems and methods described herein will, for a user selecting backwards motion in the airway of FIG. 6C, prevent the view the user sees from being displayed as if the virtual camera was located outside of the airway at the forking branch of the airways.

[0051] FIG. 7 is a graphical illustration 700 of the airways and vectors associated with movement within the airways of the Virtual Bronchoscopy view. Graphical illustration 700 shows the vectors and smoothing vectors at various locations within the airways, such as locations 510, 520, and 530 of FIG. 6. As shown in FIG. 7, airway passage 501 contains five locations L0-L4 (705-740) and respective view directions D0-D4 (705a-740a). Each view direction 705a-740a is illustrated as a solid vector line extending from locations 705-740.

[0052] In the case of forward motion, as the virtual camera progresses from location L0 to location L4, the virtual camera view as seen by a user at each location 705-740 is displayed in a direction along view directions 705a-740a, respectively.

[0053] In the case of backward motion, for example, traversing locations 740-730-720, each view direction displayed at a previous location, e.g., 730a and 720a, is altered by smoothing vector. For example, for a smoothing vector that is the average of the current vector and a previous vector at the current location, altered view direction 730c is illustrated by a dotted line and is shown as a bisector of 730a and 730b. Altered view direction 730c is created as a bisector of the normal view direction 730a of location L3 730, and the view direction of previous location L2 720, which is illustrated by dashed line 730b extending from location L3 730.

[0054] Similarly, for backward motion from location L3 730 to location L2 720, altered view direction 720c is illustrated by a dotted line and is shown as a bisector of normal view direction 720a of location L2 720, and the view direction of previous location L1 710, which is shown as a dashed line 720b extending from location L2 720.

[0055] Although the present disclosure has been described in terms of specific illustrative embodiments, it will be readily apparent to those skilled in this art that various modifications, rearrangements and substitutions may be made without departing from the scope of the claimed invention. For example, the determination of the smoothing vector is illustrated above as being performed online or dynamically during movement of the virtual camera. It is contemplated that in other embodiments smoothing vectors may be determined offline or prior to the start of the navigation mode at predetermined locations throughout the airways. This other embodiment may be beneficial when utilizing more complex methods for determining smoothing vectors or other vectors for optimizing the virtual camera view when moving in a backward direction. The scope of the present disclosure is defined by the claims appended hereto.

[0056] In addition to the aforementioned, reference is made to following commonly assigned applications, which describe features of image processing and user-interface updating, among other features which are relevant to the systems described herein: U.S. Provisional Patent Application No. 62/020,240, entitled "System And Method For Navigating Within The Lung," filed on July 2, 2014; U.S. Provisional Patent Application No. 62/020,220 entitled "Real-Time Automatic Registration Feedback," filed on July 2, 2014; U.S. Provisional Patent Application No. 62/020,177, entitled "Methods for Marking Biopsy Location," filed on July 2, 2014; U.S. Provisional Patent Application No. 62/020,242, entitled "Unified Coordinate System For Multiple CT Scans Of Patient Lungs," filed on July 2, 2014; U.S. Provisional Patent Application No. 62/020,245, entitled "Alignment CT," filed on July 2, 2014, by Klein et al.; U.S. Provisional Patent Application No. 62/020,250, entitled "Algorithm for Fluoroscopic Pose Estimation," filed on July 2, 2014; U.S. Provisional Patent Application No. 62/020,253, entitled "Trachea Marking," filed on July 2, 2014; U.S. Provisional Patent Application No. 62/020,261, entitled "Lung And Pleura Segmentation," filed on July 2, 2014; U.S. Provisional Patent Application No. 62/020,258, entitled "Cone View - A Method Of Providing Distance And Orientation Feedback While Navigating In 3D," filed on July 2, 2014; U.S. Provisional Patent Application No. 62/020,262, entitled "Dynamic 3D Lung Map View for Tool Navigation Inside the Lung," filed on July 2, 2014; U.S. Provisional Patent Application No. 62/020,261 entitled "System and Method for Segmentation of Lung," filed on July 2, 2014; and U.S. Provisional Patent Application No. 62/020,257, entitled "Automatic Detection Of Human Lung Trachea," filed on July 2, 2014, All these references are directed to aspects of processing the DICOM images, detecting the trachea, navigating within the lung, and displaying the DICOM images and processed images to provide enhanced clarity and performance for analysis, diagnosis, and treatment systems relating to, among other things, lung treatment planning and navigation.


Claims

1. A method implemented by a computer device (100) including a memory (104) and a display (102) for displaying virtual bronchoscopy views of a virtual camera navigated by a user through an airway of a virtual bronchoscopy, the method comprising:

in response to the user setting (305) the location of the virtual camera in the virtual bronchoscopy:

determining (310) the location Li and direction of view Di of the virtual camera;

storing (320) at step Si the location Li and the direction Di in the memory; and

obtaining and displaying (315, 325) on the display (102) the virtual camera view Ci corresponding to the location Li and the direction Di;

in response to the user setting a further location corresponding to movement through the airway of the virtual camera in the virtual bronchoscopy:

determining (330) the further location Li+1 location and the direction of view Di+1 of the virtual camera;

determining (335, 360) whether the movement is in a forward direction or a backward direction;

if it is determined (335) that the further movement is in the forward direction, storing (345) at step Si+1 the further location Li+1 location and the direction of view Di+1 of the virtual camera in the memory, obtaining and displaying (340, 350) on the display (102) a further virtual camera view Ci+1 corresponding to the further location Li+1 and direction Di+1, and setting (355) step Si+1 as step Si; and

if it is determined (360) that movement is in the backward direction, retrieve (370) from the memory the view direction Di and the preceding direction Di-1, calculating (375) a smoothing vector V based on the direction Di and the preceding direction Di-1, obtaining (380) and displaying (385) on the display (102) a virtual camera view CNi+1 based on the smoothing vector V, and setting (390) step Si+1 as step Si.


 
2. The method according to claim 1, wherein the locations Li, Li+1 are determined based on the location of a pointer or cursor on the display (102) which is displaying the virtual camera views.
 
3. The method according to claim 2, wherein determining whether the further movement is in a forward direction or a backward direction includes:

determining (405) the coordinates of a current pointer location;

determining (410) the coordinates of a next pointer location;

calculating (415, 420) the difference between the coordinates of the next pointer location and the coordinates of the current pointer location;

if the calculated difference is positive, determining (335) that the further movement is in the backward direction; and

if the calculated difference is negative, determining (360) that the further movement is in the forward direction.


 
4. The method according to any preceding claim, wherein determining the smoothing vector includes:

determining a first vector based on the current location Li and direction Di;

determining a second vector based on the preceding location Li-1 and direction Di-1; and

averaging the first vector and the second vector to obtain the smoothing vector.


 
5. The method according to any one of claims 1 to 3, wherein the smoothing vector is determined using a spline or a Lanczos algorithm.
 
6. The method according to claim 5, wherein the spline is a spline of order two or a spline of order four.
 
7. The method according to claim 1, 2 or 3, wherein determining the smoothing vector includes determining a vector having a direction between the directions Di and Di-1.
 
8. The method of any preceding claim, wherein the locations Li, Li+1and directions Di, Di+1 are stored in a stack.
 
9. An apparatus (100) for displaying virtual bronchoscopy views of a virtual camera navigated through an airway of a virtual bronchoscopy, comprising:

a network interface configured to receive position information of a navigation instrument which is configured to set the location of the virtual camera from at least one position sensor of the navigation instrument, the position information including physical locations;

a memory (104) storing a plurality of virtual camera views of the virtual bronchoscopy, instructions, locations, and directions of view of the virtual camera at the locations;

a processor (106) configured to execute the instructions, wherein the instructions, when executed by the processor, cause the processor to:
respond to the user setting (305) the location of the virtual camera in the virtual bronchoscopy by:

determining (310) the location Li and direction of view Di of the virtual camera;

storing (320) at step Si the location Li and the direction Di in the memory; and

obtaining and displaying (315, 325) the virtual camera view Ci corresponding to the location Li and the direction Di;

and respond to the user setting a further location corresponding to movement through the airway of the virtual camera in the virtual bronchoscopy by:

determining (330) the further location Li+1 location and the direction of view Di+1 of the virtual camera;

determining (335, 360) whether the movement is in a forward direction or a backward direction;

if it is determined (335) that the further movement is in the forward direction, storing at step Si+1 (345) the further location Li+1 location and the direction of view Di+1 of the virtual camera in the memory, obtaining and displaying (340, 350) a further virtual camera view Ci+1 corresponding to the further location Li+1 and direction Di+1, and setting (355) step Si+1 as step Si; and

if it is determined (360) that movement is in the backward direction, retrieving (370) from the memory the view direction Di and the preceding direction Di-1, calculating (375) a smoothing vector V based on the direction Di and the preceding direction Di-1, obtaining (380) and displaying (385) a virtual camera view CNi+1 based on the smoothing vector V, and setting (390) step Si+1 as step Si.


 
10. The apparatus according to claim 9, wherein the locations Li, Li+1 are determined based on the location of a pointer on a display (102) of the apparatus.
 
11. The apparatus according to claim 9 or 10, wherein the instructions, when executed by the processor, further cause the processor to:

determine (405) the coordinates of a current pointer location;

determine (41) the coordinates of a next pointer location;

calculate (415, 420) the difference between a coordinate of the current location and a coordinate of the next location;

if the calculated difference is positive, determine (335) that the movement is in the backward direction; and

if the calculated difference is negative, determine (360) that the movement is in the forward direction.


 
12. The apparatus according to claim 9, 10 or 11, wherein the instructions, when executed by the processor, further cause the processor to:

determine a first vector based on the current location Li and direction Di;

determine a second vector based on the preceding location Li-1 and direction Di-1; and average the first vector and the second vector to obtain the smoothing vector.


 
13. The apparatus according to claim 9. 10, 11 or 12, wherein the instructions, when executed by the processor, cause the processor to determine the smoothing vector having a direction that is between the directions Di and Di-1.
 
14. The apparatus according to claim 9. 10, or 11, wherein the instructions, when executed by the processor, cause the processor to determine the smoothing vector using a spline or a Lanczos algorithm.
 
15. The apparatus according to claim 14, wherein the spline is a spline of order two or a spline of order four.
 


Ansprüche

1. Computer (100) implementiertes Verfahren , beinhaltend einen Speicher (104) und eine Anzeige (102) zum Anzeigen von virtuellen Bronchoskopie-Ansichten einer virtuellen Kamera, die von einem Benutzer durch einen Atemweg einer virtuellen Bronchoskopie geführt wird, wobei das Verfahren umfasst:

als Antwort darauf, dass der Benutzer die Position der virtuellen Kamera in der virtuellen Bronchoskopie einstellt (305);
Bestimmen (310) der Position Li und der Blickrichtung Di der virtuellen Kamera; Speichern (320) der Position Li und der Richtung Di im Schritt Si im Speicher; und Erhalten und Anzeigen (315, 325) der virtuellen Kameraansicht Ci entsprechend der Position Li und der Richtung Di auf der Anzeige (102);

als Antwort darauf, dass der Benutzer eine weitere Position entsprechend der Bewegung durch den Atemweg der virtuellen Kamera in der virtuellen Bronchoskopie einstellt:

Bestimmen (330) der weiteren Position Li+1 und der Blickrichtung Di+1 der virtuellen Kamera;

Bestimmen (335, 360), ob die Bewegung in eine Vorwärtsrichtung oder eine Rückwärtsrichtung geht;

wenn bestimmt wird (335), dass die weitere Bewegung in die Vorwärtsrichtung geht, Speichern (345) in Schritt Si+1 der weiteren Position Li+1 und der Blickrichtung Di+1 der virtuellen Kamera in dem Speicher, Erhalten und Anzeigen (340, 350) einer weiteren virtuellen Kameraansicht Ci+1 auf der Anzeige (102), die der weiteren Position Li+1 und der Richtung Di+1 entspricht, und Einstellen (355) von Schritt Si+1 als Schritt Si; und

wenn bestimmt wird (360), dass die Bewegung in die Rückwärtsrichtung geht, Abrufen aus dem Speicher der Blickrichtung Di und der vorhergehenden Richtung Di-1, Berechnen (375) eines Glättungsvektors V basierend auf der Richtung Di und der vorhergehenden Richtung Di-1, Erhalten (380) und Anzeigen (385) einer virtuellen Kameraansicht CNi+1 auf der Anzeige (102) basierend auf dem Glättungsvektor V und Einstellen (390) von Schritt Si+1 als Schritt Si.


 
2. Verfahren nach Anspruch 1, wobei die Positionen Li, Li+1 basierend auf der Position eines Zeigers oder eines Cursors auf der Anzeige (102) bestimmt werden, die die virtuellen Kameraansichten anzeigt.
 
3. Verfahren nach Anspruch 2, wobei das Bestimmen, ob die weitere Bewegung in eine Vorwärtsrichtung oder eine Rückwärtsrichtung geht, Folgendes einschließt:

Bestimmen (405) der Koordinaten einer aktuellen Zeigerposition;

Bestimmen (410) der Koordinaten einer nächsten Zeigerposition;

Berechnen (415, 420) der Differenz zwischen den Koordinaten der nächsten Zeigerposition und den Koordinaten der aktuellen Zeigerposition;

wenn die berechnete Differenz positiv ist, Bestimmen (335), dass die weitere Bewegung in die Rückwärtsrichtung geht und

wenn die berechnete Differenz negativ ist, Bestimmen (360), dass die weitere Bewegung in die Vorwärtsrichtung geht.


 
4. Verfahren nach einem der vorhergehenden Ansprüche, wobei das Bestimmen des Glättungsvektors umfasst:

Bestimmen eines ersten Vektors basierend auf der aktuellen Position Li und der Richtung Di; Bestimmen eines zweiten Vektors basierend auf der Reifenvorgängerposition Li-1 und der Richtung Di-1; und

Mitteln des ersten Vektors und des zweiten Vektors, um den Glättungsvektor zu erhalten.


 
5. Verfahren nach einem der Ansprüche 1 bis 3, wobei der Glättungsvektor unter Verwendung einer Spline oder eines Lanczos Algorithmus ermittelt wird.
 
6. Verfahren nach Anspruch 5, wobei die Spline eine Spline der Ordnung zwei oder eine Spline der Ordnung vier ist.
 
7. Verfahren nach Anspruch 1, 2 oder 3, wobei das Bestimmen des Glättungsvektors das Bestimmen eines Vektors mit einer Richtung zwischen den Richtungen Di und Di-1 umfasst.
 
8. Verfahren nach einem der vorhergehenden Ansprüche, wobei die Positionen Li, Li+1 und Richtungen Di, Di+1 in einem Stapel gespeichert sind.
 
9. Vorrichtung (100) zum Anzeigen von virtuellen Bronchoskopie-Ansichten einer virtuellen Kamera, die durch einen Atemweg einer virtuellen Bronchoskopie geführt wird, umfassend:

eine Netzwerkschnittstelle, die zum Empfangen von Positionsinformationen eines Navigationsinstruments konfiguriert ist, das zum Einstellen der Position der virtuellen Kamera von mindestens einem Positionssensor des Navigationsinstruments konfiguriert ist, wobei die Positionsinformationen physische Orte enthalten;

einen Speicher (104), der mehrere virtuelle Kameraansichten der virtuellen Bronchoskopie, Anweisungen, Positionen und Blickrichtungen der virtuellen Kamera an den Positionen speichert;

einen Prozessor (106), der konfiguriert ist, um die Anweisungen auszuführen, wobei die Anweisungen, wenn sie vom Prozessor ausgeführt werden, den Prozessor zu Folgendem veranlassen:
Antworten auf die Einstellung (305) des Standorts der virtuellen Kamera in der virtuellen Bronchoskopie durch den Benutzer durch:

Bestimmen (310) der Position Li und der Blickrichtung Di der virtuellen Kamera;

Speichern (320), im Schritt Si, der Position Li und der Richtung Di im Speicher; und

Erhalten und Anzeigen (315, 325) der virtuellen Kameraansicht Ci, die der Position Li und der Richtung Di entspricht;

Antworten darauf, dass der Benutzer eine weitere Position entsprechend der Bewegung der virtuellen Kamera durch den Atemweg in der virtuellen Bronchoskopie einstellt, durch:

Bestimmen (330) der weiteren Position Li+1 und der Blickrichtung Di+1 der virtuellen Kamera;

Bestimmen (335, 360), ob die Bewegung in eine Vorwärtsrichtung oder eine Rückwärtsrichtung geht;

wenn bestimmt wird (335), dass die weitere Bewegung in die Vorwärtsrichtung geht, Speichern in Schritt Si+1 (345) der weiteren Position Li+1 und der Blickrichtung Di+1 der virtuellen Kamera in dem Speicher, Erhalten und Anzeigen (340, 350) einer weiteren virtuellen Kameraansicht Ci+1, die der weiteren Position Li+1 und der Richtung Di+1 entspricht, und Einstellen (355) von Schritt Si+1 als Schritt Si; und

wenn bestimmt wird (360), dass die Bewegung in die Rückwärtsrichtung geht, Abrufen (370) der Blickrichtung Di und der vorhergehenden Richtung Di-1 aus dem Speicher, Berechnen (375) eines Glättungsvektors V basierend auf der Richtung Di und der vorhergehenden Richtung Di-1, Erhalten (380) und Anzeigen (385) einer virtuellen Kameraansicht CNi+1 basierend auf dem Glättungsvektor V und Einstellen (390) von Schritt Si+1 als Schritt Si.


 
10. Vorrichtung nach Anspruch 9, wobei die Positionen Li, Li+1 basierend auf der Position eines Zeigers auf einer Anzeige (102) der Vorrichtung bestimmt werden.
 
11. Vorrichtung nach Anspruch 9 oder 10, wobei die Anweisungen, wenn sie durch den Prozessor ausgeführt werden, den Prozessor ferner zu Folgendem veranlassen:

Bestimmen (405) der Koordinaten einer aktuellen Zeigerposition;

Bestimmen (41) der Koordinaten einer nächsten Zeigerposition;

Berechnen (415, 420) der Differenz zwischen einer Koordinate der aktuellen Position und einer Koordinate der nächsten Position;

wenn die berechnete Differenz positiv ist, Bestimmen (335), dass die Bewegung in die Rückwärtsrichtung geht; und

wenn die berechnete Differenz negativ ist, Bestimmen (360), dass die Bewegung in die Vorwärtsrichtung geht.


 
12. Vorrichtung nach Anspruch 9, 10 oder 11, wobei die Anweisungen, wenn sie durch den Prozessor ausgeführt werden, den Prozessor ferner zu Folgendem veranlassen:

Bestimmen eines ersten Vektors basierend auf der aktuellen Position Li und der Richtung Di;

Bestimmen eines zweiten Vektors basierend auf der vorhergehenden Position Li-1 und der Richtung Di-1; und Mitteln des ersten Vektors und des zweiten Vektors, um den Glättungsvektor zu erhalten.


 
13. Vorrichtung nach Anspruch 9, 10, 11 oder 12, wobei die Anweisungen, wenn sie vom Prozessor ausgeführt werden, den Prozessor dazu veranlassen, den Glättungsvektor mit einer Richtung zu bestimmen, die zwischen den Richtungen Di und Di-1 liegt.
 
14. Vorrichtung nach Anspruch 9, 10 oder 11, wobei die Anweisungen, wenn sie vom Prozessor ausgeführt werden, den Prozessor dazu veranlassen, den Glättungsvektor unter Verwendung eines Spline- oder eines Lanczos-Algorithmus zu bestimmen.
 
15. Vorrichtung nach Anspruch 14, wobei die Spline eine Spline der Ordnung zwei oder eine Spline der Ordnung vier is^#t.
 


Revendications

1. Procédé mis en œuvre par un dispositif informatique (100) comportant une mémoire (104) et un dispositif d'affichage (102) servant à afficher des vues de bronchoscopie virtuelle d'une caméra virtuelle naviguée par un utilisateur à travers des voies respiratoires d'une bronchoscopie virtuelle, le procédé comprenant :

en réponse à la définition par l'utilisateur (305) de l'emplacement de la caméra virtuelle dans la bronchoscopie virtuelle :

la détermination (310) des emplacement Li et direction de vue Di de la caméra virtuelle ;

l'enregistrement (320) lors de l'étape Si de l'emplacement Li et de la direction Di dans la mémoire ; et

l'obtention et l'affichage (315, 325) sur le dispositif d'affichage (102) de la vue de caméra virtuelle Ci correspondant à l'emplacement Li et à la direction Di ;

en réponse à la définition par l'utilisateur d'un emplacement complémentaire correspondant à un mouvement à travers les voies respiratoires de la caméra virtuelle dans la bronchoscopie virtuelle :

la détermination (330) de l'emplacement Li+1 complémentaire et de la direction de vision Di+1 de la caméra virtuelle ;

la détermination (335, 360) du fait de savoir si le mouvement se fait dans une direction de marche avant ou une direction de marche arrière ;

s'il est déterminé (335) que le mouvement complémentaire se fait dans la direction de marche avant, l'enregistrement (345) lors de l'étape Si+1 de l'emplacement complémentaire Li+1 et de la direction de vue Di+1 de la caméra virtuelle dans la mémoire, l'obtention et l'affichage (340, 350) sur le dispositif d'affichage (102) d'une vue de caméra virtuelle Ci+1 complémentaire correspondant aux emplacement Li+1 et direction Di+1 complémentaires, et la définition (355) de l'étape Si+1 comme étant l'étape Si ; et

s'il est déterminé (360) que le mouvement se fait dans la direction de marche arrière, la récupération (370) depuis la mémoire de la direction de vue Di et la direction précédente Di-1, le calcul (375) d'un vecteur de lissage V en fonction de la direction Di et la direction précédente Di-1, l'obtention (380) et l'affichage (385) sur le dispositif d'affichage (102) d'une vue de caméra virtuelle CNi+1 en fonction du vecteur de lissage V, et la définition (390) de l'étape Si+1 comme étant l'étape Si.


 
2. Procédé selon la revendication 1, dans lequel les emplacements Li, Li+1 sont déterminés en fonction de l'emplacement d'un pointeur ou d'un curseur sur le dispositif d'affichage (102) qui affiche les vues de la caméra virtuelle.
 
3. Procédé selon la revendication 2, dans lequel la détermination du fait de savoir si le mouvement complémentaire se fait dans une direction de marche avant ou une direction de marche arrière comporte :

la détermination (405) des coordonnées d'un emplacement de pointeur actuel ;

la détermination (410) des coordonnées d'un emplacement de pointeur suivant ;

le calcul (415, 420) de la différence entre les coordonnées de l'emplacement de pointeur suivant et les coordonnées de l'emplacement de pointeur actuel ;

si la différence calculée est positive, la détermination (335) du fait que le mouvement complémentaire se fait dans la direction de marche arrière ; et

si la différence calculée est négative, la détermination (360) du fait que le mouvement complémentaire se fait dans la direction de marche avant.


 
4. Procédé selon l'une quelconque des revendications précédentes, dans lequel la détermination du vecteur de lissage comporte :

la détermination d'un premier vecteur en fonction de l'emplacement Li et de la direction Di actuels ;

la détermination d'un second vecteur en fonction des emplacement Li-1 et direction Di-1 précédents; et

l'établissement de la moyenne du premier vecteur et du second vecteur pour obtenir le vecteur de lissage.


 
5. Procédé selon l'une quelconque des revendications 1 à 3, dans lequel le vecteur de lissage est déterminé à l'aide d'une spline ou d'un algorithme de Lanczos.
 
6. Procédé selon la revendication 5, dans lequel la spline est une spline d'ordre deux ou une spline d'ordre quatre.
 
7. Procédé selon la revendication 1, 2 ou 3, dans lequel la détermination du vecteur de lissage comporte la détermination d'un vecteur ayant une direction entre les directions Di et Di-1.
 
8. Procédé selon l'une quelconque des revendications précédentes, dans lequel les emplacements Li, Li+1 et les directions Di, Di+1 sont enregistrés en pile.
 
9. Appareil (100) d'affichage de vues de bronchoscopie virtuelle d'une caméra virtuelle naviguée à travers les voies aériennes d'une bronchoscopie virtuelle, comprenant :

une interface réseau configurée pour recevoir des informations de position d'un instrument de navigation qui est configuré pour définir l'emplacement de la caméra virtuelle depuis au moins un capteur de position de l'instrument de navigation, les informations de position comportant des emplacements physiques ;

une mémoire (104) enregistrant une pluralité de vues de caméra virtuelle de la bronchoscopie virtuelle, des instructions, des emplacements, et des directions de vue de la caméra virtuelle aux emplacements ;

un processeur (106) configuré pour exécuter les instructions, dans lequel les instructions, lorsqu'elles sont exécutées par le processeur, amènent le processeur à :
répondre à la définition par l'utilisateur (305) de l'emplacement de la caméra virtuelle dans la bronchoscopie virtuelle :

en déterminant (310) l'emplacement Li et la direction de vue Di de la caméra virtuelle ;

en enregistrant (320) lors de l'étape Si l'emplacement Li et la direction Di dans la mémoire ; et

en obtenant et en affichant (315, 325) la vue de caméra virtuelle Ci correspondant à l'emplacement Li et à la direction Di ;

et à répondre à la définition par l'utilisateur d'un emplacement complémentaire correspondant au mouvement à travers les voies respiratoires de la caméra virtuelle dans la bronchoscopie virtuelle :

en déterminant (330) l'emplacement Li+1 complémentaire et la direction de vision Di+1 de la caméra virtuelle ;

en déterminant (335, 360) si le mouvement se fait dans une direction de marche avant ou une direction de marche arrière ;

s'il est déterminé (335) que le mouvement complémentaire se fait dans la direction de marche avant, en enregistrant lors de l'étape Si+1 (345) l'emplacement complémentaire Li+1 et la direction de vue Di+1 de la caméra virtuelle dans la mémoire, en obtenant et en affichant (340, 350) une vue de caméra virtuelle complémentaire Ci+1 correspondant aux emplacement Li+1 et direction Di+1 complémentaires, et en définissant (355) l'étape Si+1 comme étant l'étape Si ; et

s'il est déterminé (360) que le mouvement se fait dans la direction de marche arrière, en récupérant (370) depuis la mémoire la direction de vue Di et la direction précédente Di-1, en calculant (375) un vecteur de lissage V en fonction de la direction Di et de la direction précédente Di-1, en obtenant (380) et en affichant (385) une vue de caméra virtuelle CNi+1 en fonction du vecteur de lissage V, et en définissant (390) l'étape Si+1 comme étant l'étape Si.


 
10. Appareil selon la revendication 9, dans lequel les emplacements Li, Li+1 sont déterminés en fonction de l'emplacement d'un pointeur sur un dispositif d'affichage (102) de l'appareil.
 
11. Appareil selon la revendication 9 ou 10, dans lequel les instructions, lorsqu'elles sont exécutées par le processeur, amènent en outre le processeur à :

déterminer (405) les coordonnées d'un emplacement de pointeur actuel ;

déterminer (41) les coordonnées d'un emplacement de pointeur suivant ;

calculer (415, 420) la différence entre une coordonnée de l'emplacement actuel et une coordonnée de l'emplacement suivant ;

si la différence calculée est positive, déterminer (335) que le mouvement se fait dans la direction de marche arrière ; et

si la différence calculée est négative, déterminer (360) que le mouvement se fait dans la direction de marche avant.


 
12. Appareil selon la revendication 9, 10 ou 11, dans lequel les instructions, lorsqu'elles sont exécutées par le processeur, amènent en outre le processeur à :

déterminer un premier vecteur en fonction des emplacement Li et direction Di actuels ;

déterminer un second vecteur en fonction des emplacement Li-1 et direction Di-1 précédents ; et établir la moyenne du premier vecteur et du second vecteur pour obtenir le vecteur de lissage.


 
13. Appareil selon la revendication 9, 10, 11 ou 12, dans lequel les instructions, lorsqu'elles sont exécutées par le processeur, amènent le processeur à déterminer le vecteur de lissage ayant une direction qui est entre les directions Di et Di-1.
 
14. Appareil selon la revendication 9, 10 ou 11, dans lequel les instructions, lorsqu'elles sont exécutées par le processeur, amènent le processeur à déterminer le vecteur de lissage à l'aide d'une spline ou d'un algorithme de Lanczos.
 
15. Appareil selon la revendication 14, dans lequel la spline est une spline d'ordre deux ou une spline d'ordre quatre.
 




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REFERENCES CITED IN THE DESCRIPTION



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Patent documents cited in the description