System and method for measuring size of electrode probe in ablation procedure

Abstract

Systems and methods for ablating tissue within a vertebral body. A shaft of the drill bit is guided through the access cannula to form a tissue path. A first marker or a second marker on the shaft of the drill bit is determined to be in registration with the cannula hub of the entry cannula. The first indicia and the second indicia may be different colors. The color is associated with complementary indicia associated with the first probe and the second probe. Based on this association, either the first probe or the second probe is selected to guide it through the access cannula into the formed tissue path to ablate tissue. The indicia may be positioned longitudinally on the drill bit shaft, for example embedded along a side of the drill bit shaft. The indicia may substantially coincide, and the length of the second indicia may be greater than the length of the first indicia.

Description

[0001] Priority declaration

[0002] This application claims priority and all benefits of U.S. Provisional Patent Application No. 69 / 391,442 filed on July 22, 2022, the entire contents of which are incorporated herein by reference. Background Art

[0003] Radiofrequency (RF) energy is used to ablate diseased tissue such as sensory nerves, intraosseous nerves or intraosseous tumors, as well as other anatomical structures. The electrode probe can be coupled to an electrosurgical console, and the RF energy is conducted from the transmitter of the electrode probe to adjacent tissue to cause damage at the treatment site. Of particular interest is the destruction of intraosseous tumors within vertebral bodies, where the RF energy heats the tissue to destroy the cells of the tumor.

[0004] The transpedicular approach includes guiding an access cannula through the pedicle of a vertebral body. An electrode probe can be guided through the access cannula to be positioned within or near at least a portion of a tumor. It is desirable to ablate as much of the tumor as possible, and therefore, it is known to provide a kit of electrode probes each having one of a plurality of "sizes" selected therefrom, more specifically, an electrode probe having an increased transmitter length to generate an ablation zone of a greater width or length across the tumor. Regardless of the selected size of the electrode probe, the proximal end of the proximal transmitter should not remain within the access cannula to avoid electrical shorting or other suboptimal ablation patterns. At the same time, due to the fibrous tissue characteristics of the tumor itself and the relative fragility of the electrode probe, it is usually necessary to perforate or drill a tissue path through at least a portion of the tumor. If the tissue path is insufficient in length or if an incorrect electrode probe is selected from the kit for a tissue path of a given length, contact between the distal end of the electrode probe and the end of the tissue path will prevent the proximal transmitter from being exposed within the access cannula.

[0005] It is known to provide a mark on the shaft of a surgical instrument. In one example, the mark is a thin ring of fixed increments to correlate with the numerical depth at which the distal portion of the instrument is exposed beyond the entry cannula. Such a mark does not intuitively provide the user with information about the corresponding size of the electrode probe to be selected. In other words, it is preferably not necessary for the user to manually count the exposed ring-type marks to then calculate and determine the corresponding size of the electrode probe. For another example, U.S. Patent No. 10,729,490, granted on August 4, 2020 (the entire contents of which are incorporated herein by reference), discloses a system in which a ring-type mark on a drill bit is aligned with the entry cannula to provide an indication of the final size of the ablation zone formed using the corresponding electrode probe, which is also referred to as ablation zone mapping in the patent. In order to provide its intended benefits, such a system requires one of the thin rings to be precisely aligned with the entry cannula, which can be correlated with the suboptimal depth of the tissue path formed by the drill bit. Alternatively, the optimal depth formed by the drill bit (e.g., as desired by the user) can result in misalignment of the ring-type mark, in which case the ablation zone mapping will be inaccurate.

[0006] Therefore, there is a need in the art for improved systems and methods to provide intuitive selection of electrode probe size based on a tissue path formed by a drill having a user-selected depth. It is further desirable to provide easily identifiable information about the location of the transmitter within the formed tissue path. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a view of a vertebra including a pedicle through which an access cannula is introduced. A drill bit is introduced through the access cannula to form a tissue path through a tumor within the bone.

[0008] Figure 2A is a front view of the ablation system, which includes an access cannula, a drill bit, and two different sized electrode probes.

[0009] Figure 2B is a front view of the ablation system, which includes an access cannula, a drill bit, and four different sized electrode probes.

[0010] Figure 3 The system is shown in an arrangement in which a tissue path is formed by a drill bit and a distal margin of a first landmark is aligned with an access cannula. A first probe can be positioned within the tissue path for an end of the first probe to be adjacent to an end of the tissue path.

[0011] Figure 4The system is shown in another arrangement in which the tissue path is formed by the drill bit and the proximal edge of the first landmark is aligned with the access cannula.The first probe can be positioned within the tissue path for spacing an end of the first probe from an end of the tissue path.

[0012] Figure 5 The system is shown in another arrangement in which the tissue path is formed by the drill bit and the distal edge of the second landmark is aligned with the access cannula.A second probe can be positioned within the tissue path for an end of the second probe adjacent an end of the tissue path.

[0013] Figure 6 The system is shown in another arrangement in which the tissue path is formed by the drill bit and the proximal edge of the second landmark is aligned with the access cannula.The second probe can be positioned within the tissue path for spacing the end of the second probe from the end of the tissue path.

[0014] Fig. 7A 2 is a front view of the drill bit.

[0015] Figure 7B is a detailed view of the drill bit's markings within circle 7B.

[0016] Figure 7C is a detailed view of another implementation of a drill bit with four markings corresponding to one of four different sized electrode probes.

[0017] Figure 8 is a front view of another implementation of the drill bit, wherein the mark is an opaque band.

[0018] Fig. 9 is a front view of another implementation of the drill bit, wherein the mark is a semi-transparent band. DETAILED DESCRIPTION

[0019] The present disclosure relates to an ablation system 20 in which the size of an electrode probe can be efficiently and intuitively determined based on the depth of a tissue path formed in tissue (eg, through a tumor (T) within a vertebral body) by a drill bit 24. Figure 12, the ablation system 20 includes an entry cannula 22, a drill bit 24, a first probe 26, and a second probe 28. The ablation system 20 also includes an electrosurgical console (not shown), and the first probe 26 and the second probe 28 are configured to be removably connected to the electrosurgical console to generate and transmit RF energy. An exemplary console is disclosed in the commonly owned International Publication No. WO2023 / 009697 published on February 2, 2023, the entire contents of which are incorporated herein by reference. As will be further described, the entry cannula 22 is configured to be percutaneously guided through the pedicle of the vertebral body, and then the drill bit 24 is guided through the entry cannula 22 to form a tissue path. Figure 1 The drill bit 24 is shown further forming a tissue path through the tumor (T) within the vertebral body. The drill bit 24 is removed from the access cannula 22, and at least one of the first probe 26 and the second probe 28 is introduced through the access cannula for positioning the proximal transmitter 30 and the distal transmitter 32 within the tissue path (see Figures 3 to 6 ). The electrosurgical console is operated to transmit RF energy through the transmitters 30, 32, and the energy is delivered to and destroys the cells of the tumor.

[0020] The access cannula 22 includes a cannula hub 34 and a cannula shaft 36 extending distally from the cannula hub 34 to provide a distal end 38 of the access cannula 22. A trocar (not shown) can be removably disposed within the access cannula 22 and includes a sharp tip configured to pierce cortical bone during percutaneous insertion of the access cannula 22. The cannula hub 34 includes a proximal surface 40 that provides a visual and structural reference that will be described in further detail. It should be understood that the access cannula 22 may include a Luer connector (not shown) coupled to the cannula hub 34, through which the drill bit 24, the first probe 26, and the second probe 28 are configured to be guided. In this arrangement, the proximal edge of the Luer connector can provide a visual and structural reference.

[0021] The first probe 26 and the second probe 28 each include a probe hub 42 and a probe shaft 44 extending from the probe hub 42. The probe hub 42 provides a user with a handle for grasping a corresponding one of the first probe 26 and the second probe 28. The probe hub 42 may include a hub neck 46 that defines a distal surface 48 of the probe hub 42, wherein the probe shaft 44 extends from the hub neck 46. The proximal transmitter 30 and the distal transmitter 32 are disposed on the probe shaft 44. The distal transmitter 32 may be spaced apart from the proximal transmitter 30 by a portion of the probe shaft 44 so that the first probe 26 and the second probe 28 are self-grounded bipolar probes. The distal transmitter 32 may define the distal ends 50 of the first probe 26 and the second probe 28. More details of the probes are disclosed in the commonly owned International Publication No. WO2020 / 198150 published on November 5, 2020, the entire contents of which are incorporated herein by reference. The first probe 26 and the second probe 26 have different sizes. Specifically, Figure 2A and Figure 2B It is shown that the first probe 26 can be considered smaller than the second probe 28. The probe shaft 44 can include a length defined between a distal end 50 and a proximal end 52, the proximal end 52 being located at an interface with the probe hub 42. The length of the probe shaft 44 of the first probe 26 is less than the length of the probe shaft 44 of the second probe 28. It should be further understood that the effective tip area 54 of the first probe 26 (defined between the distal end 50 and the proximal end 56 of the proximal transmitter 30) is less than the corresponding effective tip area 54 of the second probe 28. In other words, the proximal transmitter 30 and the distal transmitter 32 of the second probe 28 can be larger.

[0022] Reference now Figure 1 , Figure 2A , Figure 2B , Fig. 7A and Figure 7B , the drill bit 24 includes a drill hub 58 and a drill shaft 60 extending distally from the drill hub 58. The drill shaft 60 includes a cutting geometry 62 at or near a distal end 64 of the drill shaft 60. The length of the drill shaft 60 is greater than the length of the probe shafts 44 of the first probe 26 and the second probe 28. As previously described, the drill bit 24 is configured to be coaxially guided through the access cannula 22, and the drill hub 58 can be manipulated to cause the cutting geometry 62 to form a tissue path. Figures 3 to 6A depiction of a tissue path is shown, where the tissue path can be formed as a channel having an end 66. Once the initial tissue path is formed, an exemplary workflow can include confirming the distal end 64 of the drill shaft 60 on imaging (e.g., intraoperative fluoroscopy). For example, the end 66 of the tissue path can be determined by visualizing the distal end 64 of the drill shaft 60. It is often desirable to drill to or beyond the distal edge of the tumor so that the ablation zone of the subsequently positioned first probe 26 or second probe 28 includes at least a majority or the entirety of the tumor.

[0023] The first mark 68 and the second mark 70 are positioned on the proximal portion of the drill shaft 60. The first mark 68 is positioned to be located distal to the second mark 70. The first mark 68 may include a distal edge 72 and a proximal edge 74, and the distal edge 72 and the proximal edge 74 define a length therebetween. Similarly, the second mark 70 may include a distal edge 76 and a proximal edge 78, and the distal edge 76 and the proximal edge 78 define a length therebetween. The length of the second mark 70 is greater than the length of the first mark 68. In an optional configuration, the length of the first mark 68 is greater, or the respective lengths may be the same. The length of the first mark 68 may be in the range of about 0.3 to 1.0 centimeters (cm), and more particularly in the range of about 0.4 to 0.6 cm. The length of the second mark 70 may be in the range of about 0.5 to 2.0 centimeters (cm), and more particularly in the range of about 0.75 to 1.25 cm. The length of the first mark 68 may be equal to the difference in length between the probe shaft 44 of the first probe 26 and the probe shaft 44 of the second probe 28. For example, the effective tip area 54 of the first probe 26 and the second probe 28 may be fifteen millimeters and twenty millimeters, respectively, so the length of the first mark 68 may be approximately five millimeters. The respective lengths are at least sufficient to align the first mark 68 and the second mark 70 with the proximal surface 40 of the cannula hub 34 over the range of positions of the drill bit 24 relative to the access cannula 22. In other words, it should be understood that each of the first mark 68 and the second mark 70 is not a thin ring of negligible length, which would otherwise be obscured within the cannula hub 34 with minimal distal movement of the drill bit 24 relative to the access cannula 22. In an exemplary implementation, there are exactly two marks corresponding to the first probe 26 and the second probe 28, however, more or fewer marks may be provided.

[0024] The distal edge 76 of the second mark 70 can substantially coincident with the proximal edge 74 of the first mark 68. In other words, the first mark 68 and the second mark 70 can be adjacent to or adjacent to each other so that there is almost no distance between them. Fig. 7A and Figure 7BAs best shown, only a thin portion 80 of the drill bit shaft 60 is located between the first mark 68 and the second mark 70. The thin portion 80 may be less than one millimeter, or may not exist at all. Figure 8 and Fig. 9 The first marking 68 and the second marking 70 are shown adjacent to each other.

[0025] The first and second markings 68, 70 may be disposed on or formed into the proximal portion of the drill shaft 60 in a variety of suitable manners. Fig. 7A and Figure 7B The first mark 68 and the second mark 70 are shown as being elongated, linear, and longitudinally oriented along one side of the proximal portion of the drill bit shaft. For example, the first mark 68 and the second mark 70 can be embedded in the drill bit shaft 60 and formed by a milling operation, a laser operation, etc. In one variation, the first mark 68 and the second mark 70 are elongated, linear, and longitudinally embedded along opposite sides of the proximal portion of the drill bit shaft 60. The opposite sides can be defined by being aligned with the major face 82 (shown as one) of the drill bit hub 58. Figure 8 The first mark 68 and the second mark 70 are shown as opaque bands extending around the drill bit axis 60, and Fig. 9 The first mark 68 and the second mark 70 are shown as translucent bands extending around the drill shaft 60. In yet another example, the band can be a colored adhesive applied to the drill shaft 60. Band as used herein is intended to mean a length greater than a thin loop having a negligible length.

[0026] The first mark 68 may be a first color and the second mark 70 may be a second color different from the first color. For example, the first color is blue and the second color is yellow, but other color combinations are also contemplated. Similarly, other types of marks may be utilized, such as textures, ridges, shapes, or other visually recognizable patterns that are not suitable for thin ring-type marks of negligible length. The probe hub 42 of each of the first probe 26 and the second probe 28 may include a mark 84 or label (see Figure 2A and Figure 2B), wherein the mark 84 of the first probe 26 corresponds to the first mark 68, and the mark 84 of the second probe 28 corresponds to the second mark 70. For example, the mark 84 may include text of a corresponding color. Due to the corresponding colors, the first mark 68 and the second mark 70 intuitively and quickly provide the user with information about which of the first probe 26 and the second probe 28 should be used without worrying about insufficient depth of the tissue path. In other words, the user can easily determine which of the first probe 26 and the second probe 28 matches the tissue path formed by the drill bit 24 in size based on the alignment of the first mark 68 and the second mark 70 with the visual reference provided by the proximal surface 40 of the cannula hub 34 (or Luer connector). This alignment can also provide information to the user or make the user aware of whether the probes 26, 28 will be positioned adjacent to or spaced apart from the end 66 of the tissue path. The first mark 68 and the second mark 70 do not necessarily provide any information about the size of the ablation zone or the ablation zone mapping.

[0027] like Figure 2A As shown, a first distance between a distal edge 72 of the first marker 68 and the distal end 64 of the drill shaft 60 is configured to be equal to a first probe length defined between the probe hub 42 of the first probe 26 and the distal end 50 of the probe shaft 44. Similarly, a second distance between a proximal edge 74 of the first marker 68 and the distal end 64 of the drill shaft 60 is configured to be equal to a second probe length defined between the probe hub 42 of the second probe 28 and the distal end 50 of the probe shaft 44. Therefore, if a tissue path is formed with the first marker 68 visible near the cannula hub 34, the path length of the formed tissue path may be insufficient to allow the effective tip region 54 of the second probe 28 to be positioned beyond the distal end 38 of the cannula 22.

[0028] Thus, an exemplary method may include guiding the distal end 64 of the drill shaft 60 beyond the distal end 38 of the access cannula 22 to form a tissue path having a desired length. The distal end 64 of the drill shaft 60 may be confirmed on imaging and adjusted accordingly if necessary. With the drill 24 in the desired position, the drill hub 58 is spaced apart from the cannula hub 34, and a proximal portion of the drill shaft 60 is exposed. The method includes determining whether the first mark 68 or the second mark 70 is aligned with the cannula hub 34 of the access cannula 22. Due to the contrasting colors of the first mark 68 and the second mark 70, for example, a user can quickly determine this information. Figure 3 The first marker 68 is shown aligned with the proximal surface 40 of the access cannula 22. The drill bit 24 can be removed from the access cannula 22.

[0029] The method includes correlating one of the first mark 68 and the second mark 70 that is aligned with the cannula hub 34 of the access cannula 22 with a complementary mark 84 associated with a corresponding one of the first probe 26 and the second probe 28. In an exemplary implementation, the first color or the second color that is aligned with the cannula hub 34 of the access cannula 22 is correlated with the corresponding color of the complementary mark 84. One of the first probe 26 and the second probe 28 is selected based on the corresponding color. In other words, if the first mark 68 is aligned with the cannula hub 34, it can be assumed that the path length is at least sufficient to accommodate the effective tip area 54 of the first probe 26, and if the second mark 70 is aligned with the cannula hub 34, it can be assumed that the path length is at least sufficient to accommodate the effective tip area 54 of the second probe 28. The method includes guiding the selected one of the first probe 26 and the second probe 28 through the access cannula 22 into the formed tissue path. For example, the distal surface 48 of the probe hub 42 can be positioned adjacent to the proximal surface 40 of the cannula hub 34 (or Luer connector) that provides a structural reference. Due to the relative lengths of the probe shaft 44 and the cannula shaft 36, it can also be assumed that an effective tip region 54 including a proximal end 56 of the proximal transmitter 30 is exposed outside the distal end 38 of the access cannula 22. A selected one of the first probe 26 and the second probe 28 is operated (using RF energy provided by the console) to ablate tissue adjacent to the formed tissue path.

[0030] The intuitiveness and efficiency of the ablation system 20 of the present disclosure are easily perceived. Simply put, if any portion of the first mark 68 is visible, the user understands not to use the second probe 28. Otherwise, the proximal transmitter 30 of the second probe 28 may not be exposed outside the access cannula 22 before the distal end 50 of the second probe 28 bottoms out in the tissue path. Similarly, if only the second mark 70 is visible, the user understands not to use the first probe 26 because the first probe 26 is too short to effectively occupy the formed tissue path. If the user still wishes to use the first probe 26 in this case, it can be indicated to reposition the access cannula 22 to reach the target location. In the case where the first probe 26 and the second probe 28 are packaged separately in a sterile kit, the user can advantageously avoid disassembling the unselected probes. The packaged sterile probes can be reserved for subsequent ablation procedures, thereby reducing costs and waste.

[0031] More information can be realized based on the location of the markers 72, 74, 76, 78 relative to the cannula hub 34 of the access cannula 22. In the event that the user can visualize a portion of the drill shaft 60 distal to the distal edge 72 of the first marker 68, the user will realize that the first probe 26 (and the second probe 28) is too long for the tissue path being formed. The user will realize that the drill 24 should be further advanced relative to the access cannula 22 to deepen the tissue path (e.g., at least until the distal edge 72 of the first marker 68 is aligned with the proximal surface 40). Figure 3 The distal edge 72 of the first marker 68 is shown aligned with the proximal surface 40 of the access cannula 22. This arrangement indicates that the path length is approximately equal to the distance the first probe 26 is configured to extend beyond the distal end 38 of the access cannula 22. The distal end 50 of the first probe 26 is adjacent or abutting the end 66 of the tissue path.

[0032] In some approaches, the proximal edge 74 of the first landmark 68 may be associated with registration with the cannula hub 34 . Figure 4 The proximal edge 74 of the first marker 68 is shown visible near the proximal surface 40 of the access cannula 22. The user can select the first probe 26 based on this association and guide the first probe 26 through the access cannula 22 into the formed tissue path. In this arrangement, the user will realize that with the probe hub 42 engaged with the cannula hub 34, the distal end 50 of the first probe 26 will be spaced apart from the end 66 of the tissue path. Figure 4 An unoccupied portion of the tissue path is shown. Based on the proportion of the first marker 68 visible on the cannula hub 34, the user can intuitively infer the size of the gap in the tissue path distal to the distal end 50 of the first probe 26. In other cases, the proximal edge 74 of the first marker 68 can be aligned with or just inside the cannula hub 34 so that the first marker 68 is not visible, or alternatively, a thin portion 80 between the first marker 68 and the second marker 70 can be registered with the cannula hub 34. Since the user cannot see the first marker 68, the user can select the second probe 28 based on this association, and the second probe 28 is guided through the entry cannula 22 into the formed tissue path.

[0033] In some approaches, the distal edge 76 of the second landmark 70 may be associated with registration with the cannula hub 34 . Figure 5The distal edge 76 of the second marker 70 is shown aligned with the proximal surface 40 of the access cannula 22. The user can select the second probe 28 based on this association, and the second probe 28 can be guided through the access cannula 22 into the formed tissue path. With the probe hub 42 engaged with the cannula hub 34, the distal end 50 of the second probe 28 is proximal, adjacent or abutting the end 66 of the formed tissue path. There may be a minimum gap corresponding to the distance between the proximal edge 74 of the first marker 68 and the distal edge 76 of the second marker 70.

[0034] In some approaches, the proximal edge 78 of the second landmark 70 may be associated with registration with the cannula hub 34 . Figure 6 The proximal edge 78 of the second marker 70 is shown aligned with the proximal surface 40 of the access cannula 22. The user can select the second probe 28 based on this association, and the second probe 28 can be guided through the access cannula 22 into the formed tissue path. With the probe hub 42 engaged with the cannula hub 34, the distal end 50 of the second probe 28 is spaced apart from the end 66 of the tissue path. Figure 6 Another unoccupied portion of the tissue path is shown. Based on the scale at which the second marker 70 is visible distally of the cannula hub 34 , the user can intuitively infer the size of the gap within the tissue path distally of the distal end 50 of the second probe 28 .

[0035] The objects of the present disclosure may be extended to systems including three, four or five or more probes. For example, Figure 2B and Figure 7C Represents an ablation system 20, wherein the drill shaft 60 includes a first marker 68, a second marker 70, a third marker 86, and a fourth marker 88 corresponding to the first probe 26, the second probe 28, the third probe 27, and the fourth probe 29, respectively. The third probe 27 and the fourth probe 29 and the third marker 86 and the fourth marker 88 can correspond to the first probe 26 and the second probe 28 and the first marker 68 and the second marker 70, respectively. In other words, the effective tip area 54 of the third probe 27 and the fourth probe 29 can be fifteen millimeters and twenty millimeters, respectively, and thus the length of the third marker 86 can be approximately five millimeters.

[0036] In the present implementation, the effective tip area 54 of the first probe 26 and the second probe 28 may be seven millimeters and ten millimeters, respectively, and thus the length of the first mark 68 and the second mark 70 may be approximately three millimeters and five millimeters, respectively. More specifically, the first mark 68 may include a distal edge 72 and a proximal edge 74, defining a length between the distal edge 72 and the proximal edge 74, and the second mark 70 may include a distal edge 76 and a proximal edge 78, defining a length between the distal edge 76 and the proximal edge 78. The length of the second mark 70 is greater than the length of the first mark 68. The length of the first mark 68 may be equal to the difference in length between the probe shaft 44 of the first probe 26 and the probe shaft 44 of the second probe 28. Further in the present implementation, the effective tip area 54 of the third probe 27 and the fourth probe 29 may be fifteen millimeters and twenty millimeters, respectively, and thus the length of the third mark 86 may be approximately five millimeters. The third mark 86 may include a distal edge 90 and a proximal edge 92 defining a length therebetween, and the fourth mark 88 may include a distal edge 94 and a proximal edge 96 defining a length therebetween. The length of the second mark 86 may be equal to the difference in length between the probe shaft 44 of the second probe 27 and the probe shaft 44 of the third probe 28. The length of the third mark 86 may be equal to the difference in length between the probe shaft 44 of the third probe 26 and the probe shaft 44 of the fourth probe 28. Thus, the length of the third mark 86 may be the same as the length of the second mark 70.

[0037] The first mark 68, the second mark 70, the third mark 86 and the fourth mark 88 can be elongated, linear and longitudinally oriented along one side of the proximal portion of the drill shaft. For example, the first mark 68, the second mark 70, the third mark 86 and the fourth mark 88 can be embedded in the drill shaft 60 and formed by a milling operation, a laser operation, etc. The first mark 68, the second mark 70, the third mark 86 and the fourth mark 88 can be different colors. For example, the first color is blue and the second color is pink, the third color is green, and the fourth color is yellow, but other color combinations are also contemplated. The probe hub 42 of each of the first probe 26, the second probe 27, the third probe 28 and the fourth probe 29 may include a mark 84 or a label with a corresponding mark 84 (see Figure 2A and Figure 2B ). Due to the corresponding colors, the first mark 68, the second mark 70, the third mark 86 and the fourth mark 88 intuitively and quickly provide the user with information about which of the first probe 26, the second probe 27, the third probe 28 and the fourth probe 29 should be used without worrying about insufficient tissue path depth.

[0038] Thus, an exemplary method may include guiding the distal end 64 of the drill shaft 60 beyond the distal end 38 of the access cannula 22 to form a tissue path having a desired length. The distal end 64 of the drill shaft 60 may be confirmed on imaging and adjusted accordingly if necessary. With the drill 24 in the desired position, the drill hub 58 is spaced apart from the cannula hub 34, and a proximal portion of the drill shaft 60 is exposed. The method includes determining whether the first mark 68, the second mark 70, the third mark 86, and the fourth mark 88 are aligned with the cannula hub 34 of the access cannula 22. Due to the contrasting colors of the first mark 68, the second mark 70, the third mark 86, and the fourth mark 88, for example, a user can quickly determine this information.

[0039] The method includes correlating one of the first marker 68, the second marker 70, the third marker 86, and the fourth marker 88 that is registered with the cannula hub 34 of the access cannula 22 with a complementary marker 84 associated with a corresponding one of the first probe 26, the second probe 27, the third probe 28, and the fourth probe 29. One of the first probe 26, the second probe 27, the third probe 28, and the fourth probe 29 is selected based on the corresponding color. The selected one of the first probe 26, the second probe 27, the third probe 28, and the fourth probe 29 is guided through the access cannula 22 into the formed tissue path. Due to the relative lengths of the probe shaft 44 and the cannula shaft 36, it can also be assumed that the effective tip area 54 including the proximal end 56 of the proximal transmitter 30 is exposed outside the distal end 38 of the access cannula 22. The selected one of the first probe 26, the second probe 27, the third probe 28, and the fourth probe 29 is operated to ablate tissue adjacent to the formed tissue path.

[0040] During deployment of the drill bit 24, if any portion of the first marker 68 is visible, the user understands not to use the second probe 27, the third probe 28, or the fourth probe 29. If any portion of the second marker 70 is visible, the user understands not to use the third probe 27 or the fourth probe 29. If any portion of the third marker 86 is visible, the user understands not to use the fourth probe 29. Finally, if only the fourth marker 88 is visible, the user understands not to use the first probe 26, the second probe 27, or the third probe 28 because they are too short to effectively occupy the tissue path formed. Further aspects of the method of the ablation system 20 including four probes are similar to the aspects previously described for the dual probe system and are incorporated herein by reference. As previously described, the ablation system 20 can be modified to accommodate any number of probes.

[0041] The foregoing disclosure is not intended to be exhaustive or to limit the invention to any particular form. The terms used are intended to be descriptive and not restrictive. Many modifications and variations are possible in light of the above teachings, and the invention may be practiced in a manner other than that specifically described. It will be understood that treatment parameters other than impedance and temperature may be utilized with the above techniques. Furthermore, it is contemplated that treatment parameters may be controlled or defined in a manner other than that described. It will be further understood that the objects of the present disclosure may be used with microwave energy or electrical energy other than radio frequency energy.

Claims

1. A method of ablating tissue within a vertebral body using a system, the system comprising an access cannula having a cannula hub, a drill having a drill hub, and a first probe and a second probe having different lengths and each comprising a probe hub, the method comprising: providing access to the vertebral body using the access cannula; directing a distal end of the shaft of the drill bit beyond the distal end of the access cannula to form a first tissue path having a first path length or a second tissue path having a second path length greater than the first path length, with the drill bit hub spaced apart from the cannula hub and a proximal portion of the shaft of the drill bit exposed; determining whether a first indicia of a first color or a second indicia of a second color is registered with the cannula hub of the access cannula, wherein the first indicia and the second indicia are longitudinally sized and positioned on the proximal portion of the shaft of the drill bit to be associated with a corresponding one of the first path length and the second path length for receiving a corresponding one of the first probe and the second probe; correlating one of the first color and the second color that is registered with the cannula hub of the access cannula with a corresponding color of a complementary indicia associated with a corresponding one of the first probe and the second probe; selecting one of the first probe and the second probe that is associated with each other based on one of the first color and the second color; removing the drill bit from the access cannula; guiding the selected one of the first probe and the second probe through the access cannula into the formed first tissue path or the formed second tissue path; and The selected one of the first probe and the second probe is operated to ablate tissue adjacent to the formed first tissue path or the formed second tissue path.

2. The method according to claim 1, characterized in that The method further comprises: With the first marker partially visible, associating a proximal edge of the first marker in registration with the cannula hub; selecting the first probe; and The first probe is guided through the access cannula into the formed first tissue path such that the distal end of the first probe is spaced apart from an end of the first tissue path with the first probe hub engaging the cannula hub.

3. The method according to claim 1, characterized in that The method further comprises: in a case where the first landmark is not visible, associating a proximal edge of the first landmark in registration with the cannula hub; selecting the second probe; and The second probe is guided through the access cannula into the formed second tissue path such that with the second probe hub engaging the cannula hub, the distal end of the second probe is located at an end of the second tissue path.

4. The method according to claim 1, characterized in that: The method further comprises: in the event that the first marker is not visible, correlating a thin portion of the shaft of the drill bit between the first marker and the second marker as being in registration with the cannula hub; selecting the second probe; and The second probe is guided through the access cannula into the formed second tissue path.

5. The method according to claim 1, characterized in that The method further comprises: associating a distal edge of the second landmark in registration with the cannula hub; selecting the second probe; and The second probe is guided through the access cannula into the formed second tissue path.

6. The method according to claim 1, characterized in that The method further comprises: associating a proximal edge of the second landmark in registration with the cannula hub; selecting the second probe; and The second probe is guided through the access cannula into the formed second tissue path such that the distal end of the second probe is spaced apart from the end of the second tissue path with the second probe hub engaging the cannula hub.

7. A method of ablating tissue within a vertebral body using a system comprising an access cannula having a cannula hub, a drill having a drill hub, and first and second probes having different lengths and each comprising a probe hub, the method comprising: providing access to the vertebral body using the access cannula; directing a distal end of the shaft of the drill bit beyond the distal end of the access cannula to form a first tissue path having a first path length or a second tissue path having a second path length greater than the first path length, with the drill bit hub spaced apart from the cannula hub and a proximal portion of the shaft of the drill bit exposed; determining whether a first indicia of a first color or a second indicia of a second color on the proximal portion of the shaft of the drill bit is in registration with the cannula hub of the access cannula; correlating one of the first color or the second color with a corresponding color of a complementary indicia associated with a corresponding one of the first and second probes, wherein a distal edge of the first indicia is registered with the cannula hub such that a proximal transmitter of the first probe is exposed beyond the distal end of the access cannula with the first probe hub engaged with the cannula hub and the distal end of the first probe is positioned at an end of the first tissue path, the second probe having a length such that a proximal transmitter of the second probe is not exposed beyond the distal end of the access cannula upon engagement of the distal end of the second probe with tissue at the end of the first tissue path; selecting one of the first probe and the second probe that is associated with each other based on one of the first color and the second color; removing the drill bit from the access cannula; guiding the selected one of the first probe and the second probe through the access cannula into the formed first tissue path or the formed second tissue path; and The selected one of the first probe and the second probe is operated to ablate tissue adjacent to the formed first tissue path or the formed second tissue path.

8. The method according to claim 7, characterized in that The proximal edge of the first marker is aligned with the cannula hub such that when the first probe hub is engaged with the cannula hub, the distal end of the first probe is spaced apart from the end of the first tissue path, the distal edge of the second marker is aligned with the cannula hub such that when the second probe hub is engaged with the cannula hub, the distal end of the second probe is located at the end of the second tissue path, and the proximal edge of the second marker is aligned with the cannula hub such that when the second probe hub is engaged with the cannula hub, the distal end of the second probe is spaced apart from the end of the second tissue path.

9. The method according to any one of claims 1 to 8, characterized in that After the step of imagingly confirming the distal end of the shaft of the drill bit, the step of determining whether the first mark of the first color or the second mark of the second color is registered with the cannula hub is performed.

10. The method according to any one of claims 1 to 9, characterized in that The first probe is packaged in a first probe kit and the second probe is packaged in a second probe kit, and the method further includes opening a single one of the first probe kit and the second probe kit that are associated with each other based on the one of the first color and the second color so that the second probe kit can still be used in a subsequent ablation procedure.

11. A system for ablating tissue, the system comprising: an access cannula including a cannula hub; as well as A drill bit comprising a drill hub, a drill shaft extending from the drill hub, a first mark of a first color disposed on a proximal portion of the drill shaft, and a second mark of a second color disposed on the proximal portion of the drill shaft, wherein a distal edge of the second mark substantially coincides with a proximal edge of the first mark, wherein the drill bit shaft is configured to be guided through the access cannula to align one of the first mark and the second mark with the cannula hub of the access cannula, and a first distance between a distal edge of the first mark and a distal end of the drill bit shaft is configured to be equal to a first probe length defined between a first probe hub and a first distal end of the first probe shaft, and a second distance between the distal edge of the second mark and the distal end of the drill bit shaft is configured to be equal to a second probe length defined between a second probe hub and a second distal end of the second probe shaft.

12. The system according to claim 11, characterized in that The first mark and the second mark are opaque bands extending around the drill bit axis.

13. The system according to claim 11, characterized in that The first mark and the second mark are translucent bands extending around the drill bit axis.

14. The system according to claim 11, characterized in that The first and second markers are elongated, linear, and embedded longitudinally along a side of the proximal portion of the drill shaft.

15. The system according to claim 14, characterized in that The first and second markers are elongated, linear, and longitudinally embedded along opposite sides of the proximal portion of the drill shaft.

16. The system according to claim 14 or 15, characterized in that The one side or the opposite two sides are defined by being aligned with a major surface of the drill hub.

17. The system according to any one of claims 11 to 16, characterized in that The first mark and the second mark are not circular rings.

18. A system for ablating tissue, the system comprising: an access cannula including a cannula hub; as well as A drill bit comprising a drill hub, a drill shaft extending from the drill hub, a first mark of a first color disposed on a proximal portion of the drill shaft, and a second mark of a second color disposed on the proximal portion of the drill shaft, wherein the first mark and the second mark are elongated, linear and longitudinally embedded along a side of the proximal portion of the drill shaft, the side of the proximal portion being aligned with a major surface of the drill hub, wherein the drill bit shaft is configured to be guided through the access cannula so that one of the first mark and the second mark is aligned with the cannula hub of the access cannula, and a first distance between a distal edge of the first mark and a distal end of the drill bit shaft is configured to be equal to a first probe length defined between a first probe hub and a first distal end of the first probe shaft, and a second distance between the distal edge of the second mark and the distal end of the drill bit shaft is configured to be equal to a second probe length defined between a second probe hub and a second distal end of the second probe shaft.

19. The system according to any one of claims 11 to 18, characterized in that The length of the first mark defined between the proximal edge and the distal edge of the first mark is greater than the length of the second mark defined between the distal edge and the proximal edge of the second mark. The length between.

20. A system for ablating tissue, the system comprising: an access cannula including a cannula hub; as well as A drill bit comprising a drill hub, a drill shaft extending from the drill hub, a first mark of a first color disposed on a proximal portion of the drill shaft, and a second mark of a second color disposed on the proximal portion of the drill shaft, wherein a length of the first mark defined between a proximal edge and a distal edge of the first mark is greater than a length of the second mark defined between a distal edge and a proximal edge of the second mark, wherein the drill bit shaft is configured to be guided through the access cannula to align one of the first mark and the second mark with the cannula hub of the access cannula, and a first distance between a distal edge of the first mark and the distal end of the drill bit shaft is configured to be equal to a first probe length defined between a first probe hub and a first distal end of the first probe shaft, and a second distance between the distal edge of the second mark and the distal end of the drill bit shaft is configured to be equal to a second probe length defined between a second probe hub and a second distal end of the second probe shaft.

21. The system according to any one of claims 11 to 20, characterized in that The drill bit is configured to form a first tissue path with the first landmark in registration with the cannula hub, the first tissue path having a path length insufficient to allow a second transmitter on the second probe shaft to be positioned beyond a distal end of the access cannula.

22. The system according to any one of claims 11 to 21, characterized in that The first marking is a first color and the second marking is a second color different from the first color; and optionally, the first color is blue and the second color is yellow.

23. The system according to any one of claims 11 to 22, characterized in that The drill bit also includes a third indicia of a third color disposed on a proximal portion of the drill bit shaft, and a fourth indicia of a fourth color disposed on the proximal portion of the drill bit shaft.

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