WO2015052669A1 - System for twin target stereotactic system with a phantom base to simulate the target and determine its accuracy in vitro - Google Patents

System for twin target stereotactic system with a phantom base to simulate the target and determine its accuracy in vitro Download PDF

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Publication number
WO2015052669A1
WO2015052669A1 PCT/IB2014/065164 IB2014065164W WO2015052669A1 WO 2015052669 A1 WO2015052669 A1 WO 2015052669A1 IB 2014065164 W IB2014065164 W IB 2014065164W WO 2015052669 A1 WO2015052669 A1 WO 2015052669A1
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WIPO (PCT)
Prior art keywords
target
phantom
frame
stereotactic
pointer
Prior art date
Application number
PCT/IB2014/065164
Other languages
French (fr)
Inventor
Murali Mohan SELVAM
Sadashiv BHAT
Original Assignee
Selvam Murali Mohan
Bhat Sadashiv
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by Selvam Murali Mohan, Bhat Sadashiv filed Critical Selvam Murali Mohan
Publication of WO2015052669A1 publication Critical patent/WO2015052669A1/en

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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B90/00—Instruments, implements or accessories specially adapted for surgery or diagnosis and not covered by any of the groups A61B1/00 - A61B50/00, e.g. for luxation treatment or for protecting wound edges
    • A61B90/10—Instruments, implements or accessories specially adapted for surgery or diagnosis and not covered by any of the groups A61B1/00 - A61B50/00, e.g. for luxation treatment or for protecting wound edges for stereotaxic surgery, e.g. frame-based stereotaxis
    • A61B90/11—Instruments, implements or accessories specially adapted for surgery or diagnosis and not covered by any of the groups A61B1/00 - A61B50/00, e.g. for luxation treatment or for protecting wound edges for stereotaxic surgery, e.g. frame-based stereotaxis with guides for needles or instruments, e.g. arcuate slides or ball joints
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B2017/00681—Aspects not otherwise provided for
    • A61B2017/00707—Dummies, phantoms; Devices simulating patient or parts of patient
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
    • A61B6/12—Devices for detecting or locating foreign bodies

Definitions

  • the present invention relates to a stereotactic system.
  • the invention relates to a system for twin target stereotactic system with a phantom base to simulate the target and determine its accuracy in vitro.
  • Stereotaxy is the concept of targeting a region of interest in the brain using solid geometry (Cartesian co-ordinates). Multiple stereotactic frames exist for veterinary and human use. Collectively they are called as 'Frame based Stereotaxy'.
  • stereotactic frames ranges from drug delivery to desired target, lesioning of the target, placement of electrodes at the target for deep brain stimulation or biopsy of the region. Further, the frame can be utilized for precise planning in stereotactic radio surgery. But in all these existing stereotactic frame only one target can be set at a time which in turn increases the operation time and also causes the shift of the second target as result of outflow of the cerebrospinal fluid.
  • the invention discloses a stereotactic system configured for simultaneously identifying two target focusing points.
  • the stereotactic system includes a stereotactic frame with two separate hemi-arc system symmetrically arranged in the frame.
  • the system also has a plurality of target guides, wherein each hemi-arc system has a target guide movably coupled to the hemi-arc system.
  • the system further has two localizer plate with embedded fiducials, wherein the fiducials in a localizer plate facilitate to determine the coordinates of the target.
  • the system also has a phantom frame system.
  • the phantom frame has a workstation displaying the scan image of a subject along with the target determined using the fiducials and a digital pointer.
  • a phantom pointer on the phantom frame represents the digital pointer on the workstation; the target is identified using the digital pointer which in turn sets the phantom pointer on to the target.
  • the target is simulated in the target guides by positioning the target guides with respect to the phantom pointer.
  • the target guides are attuned to achieve an optimal access position to the target by keeping the target intact.
  • the double arc stereotactic frame system disclosed gives the capability of simultaneous targeting of two targets in real time, thereby reducing the operative time and increasing the precision of the target.
  • the phantom frame system is used prior to actual surgery to simulate the precision of the procedure in vivo
  • Figure 1 illustrates the perspective view of the stereotactic frame along with the phantom frame in accordance with an embodiment of the invention.
  • Figure 2 illustrates the front view of the stereotactic frame along with the phantom frame in accordance with an embodiment of the invention
  • Figure 3 illustrates the side view of the stereotactic frame along with the phantom frame in accordance with an embodiment of the invention
  • the invention discloses a stereotactic system configured for simultaneously identifying two target focusing points.
  • the system includes a stereotactic frame having two separate hemi-arc system symmetrically arranged in the stereotactic frame.
  • the system also has a plurality of target guides, wherein each hemi-arc system has a target guide movably coupled to the hemi-arc system.
  • the system further has two localizer plate with embedded fiducials. These fiducials in the localizer plate facilitate to determine the co-ordinates of the target.
  • the system also has a phantom frame system.
  • the phantom frame system has a workstation displaying the scan image of a subject along with the target determined using the fiducials and a digital pointer.
  • a phantom pointer on the phantom frame system represents the digital pointer on the workstation.
  • the target is identified using the digital pointer which in turn sets the phantom pointer on to the target.
  • the target is simulated in the target guides by positioning the target guides with respect to the phantom pointer.
  • the stereotactic frame is secured to the subject's head using posts and pins. In most of the cases 4 posts and pins are used in order to secure the stereotactic frame on to the subject.
  • the localizer plates are then attached to the stereotactic frame, following which the subject is subjected for a scan (CT or MRI).
  • CT or MRI a scan
  • the stereotactic frame accommodates two separate hemi- arc system at the same time. The presence of two hemi-arc system allows the user to target the brain on either side (right and left) at the same given time.
  • the localizer plates are used to determine the fiducials on the imaging system.
  • the fiducials on the imaging system has been developed in such a way that the user has an idea of the depth of the target based on the co-ordinates. For example a negative target means the target is closer to the skull base.
  • the result of the scan images is fed into the system.
  • the desired targets are identified and the coordinates are also calculated using the workstation of the system.
  • the trajectory may also be planned for the target.
  • the phantom frame is then linked to the workstation of the phantom frame system.
  • the phantom pointer in the phantom frame represents the target.
  • the phantom pointer is moved to desired target using the co-ordinates obtained.
  • the accuracy may be checked on the workstation, where the tip of the phantom pointer is represented on the subject's image present in the workstation. Further, the hemi-arc assembly is then assembled on the phantom frame to simulate the target for surgery. The accuracy of the target is also checked.
  • the subject with the frame in situ is shifted to the operating room.
  • the hemi-arc assembly is then attached to the frame.
  • both sides need to be targeted (like in deep brain stimulation surgery) then two arcs are used.
  • single target is planned then a single arc is assembled and attached to the frame and surgery performed.
  • the target guide (108) is movably coupled to the hemi-arc system (104) and the target guide (110) is movably coupled to the hemi-arc system (106).
  • the phantom pointer (202) represents the position of the digital pointer in the workstation. Once the target is identified in the scan image on left side of the brain, then the target guide (108) on the left hemi-arch (104) is moved with respect to phantom pointer (202) in order to identify the target position on the target guide. Once the target is set on the target guide (108), the target guide (108) is moved in order to achieve an optimal access point. Similarly the target on the scan image on right side of the brain is identified and the digital pointer represents the target which in turn sets the phantom pointer (202).
  • the target guide (110) on the left hemi-arch (106) is moved with respect to phantom pointer (202) in order to identify the target position on the target guide.
  • the target guide (108) is moved in order to achieve an optimal access point.
  • the double arc stereotactic frame gives the capability of simultaneous targeting of two targets in real time, thereby reducing the operative time and increasing the precision of the target.
  • the Phantom base is used prior to actual surgery to simulate the precision of the procedure in vivo.
  • the stereotactic co-ordinates can be derived manually from the fiducials displayed on the medical imaging system (CT/MRI Scan) or may be derived from the software.

Abstract

The invention discloses a stereotactic system configured for simultaneously identifying two target focusing points. The stereotactic system includes a stereotactic frame having two separate hemi-arc system (104, 106) symmetrically arranged in the frame. The system also has a plurality of target guides. Each hemi- arc system (104, 106) has a target guide movably coupled to the hemi-arc system. The system further has at least one localizer plate having fiducials, wherein the fiducials in a localizer plate facilitates to identify the depth of a target based on the co-ordinates. The system further has a phantom frame system (200) which has a phantom pointer (202) representing the target. The target is simulated in the target guides (108, 110) by positioning the target guides (108, 110) with respect to the phantom pointer (202).

Description

System for twin target stereotactic system with a phantom base to simulate the target and determine its accuracy in vitro
[001] Technical Field of the Invention
[002] The present invention relates to a stereotactic system. In particular, the invention relates to a system for twin target stereotactic system with a phantom base to simulate the target and determine its accuracy in vitro.
[003] Background of the Invention
[004] Stereotaxy is the concept of targeting a region of interest in the brain using solid geometry (Cartesian co-ordinates). Multiple stereotactic frames exist for veterinary and human use. Collectively they are called as 'Frame based Stereotaxy'.
[005] The majority of the stereotactic frames that exist today use the 'centre of the arc' principle to reach the target. The co-ordinates for the target are determined using localizer with fiducials (markers) that can be visualized on imaging (CT scan or MRI scan). These fiducials actually represent the Cube / Cuboids of which the 'basic stereotaxic frame' is a representative plane.
[006] The clinical application of these stereotactic frames ranges from drug delivery to desired target, lesioning of the target, placement of electrodes at the target for deep brain stimulation or biopsy of the region. Further, the frame can be utilized for precise planning in stereotactic radio surgery. But in all these existing stereotactic frame only one target can be set at a time which in turn increases the operation time and also causes the shift of the second target as result of outflow of the cerebrospinal fluid.
[007] Most of the already existing stereotactic frames are not capable of targeting two targets simultaneously. All the stereotactic frames described with single arc with phantom base cannot target two regions simultaneously in real time. They can be used to target the second region only in sequence, i.e. one after another. Frame with double arc has no phantom base to verify the precision of the target prior to surgery.
[008] Thus, there is need of a double arc stereotactic frame that gives the capability of simultaneous targeting of two targets in real time, thereby reducing the operative time and increasing the precision of the target.
[009] Summary of the Invention
[010] According to an embodiment, the invention discloses a stereotactic system configured for simultaneously identifying two target focusing points. The stereotactic system includes a stereotactic frame with two separate hemi-arc system symmetrically arranged in the frame. The system also has a plurality of target guides, wherein each hemi-arc system has a target guide movably coupled to the hemi-arc system. The system further has two localizer plate with embedded fiducials, wherein the fiducials in a localizer plate facilitate to determine the coordinates of the target. The system also has a phantom frame system. The phantom frame has a workstation displaying the scan image of a subject along with the target determined using the fiducials and a digital pointer. A phantom pointer on the phantom frame represents the digital pointer on the workstation; the target is identified using the digital pointer which in turn sets the phantom pointer on to the target. The target is simulated in the target guides by positioning the target guides with respect to the phantom pointer.
[011] According to an embodiment, the target guides are attuned to achieve an optimal access position to the target by keeping the target intact.
[012] The double arc stereotactic frame system disclosed gives the capability of simultaneous targeting of two targets in real time, thereby reducing the operative time and increasing the precision of the target. In addition the phantom frame system is used prior to actual surgery to simulate the precision of the procedure in vivo [013] Brief Description of Drawings
[0001] The features of embodiments will become more apparent from the following detailed description of embodiments when read in conjunction with the accompanying drawings. Furthermore, elements that are known to be common and well understood to those in the industry are not depicted in order to provide a clear view of the various embodiments of the invention. Thus, in the interest of clarity and conciseness, the drawings are generalized in form.
[014] Figure 1 illustrates the perspective view of the stereotactic frame along with the phantom frame in accordance with an embodiment of the invention.
[015] Figure 2 illustrates the front view of the stereotactic frame along with the phantom frame in accordance with an embodiment of the invention
[016] Figure 3 illustrates the side view of the stereotactic frame along with the phantom frame in accordance with an embodiment of the invention
[017] Detailed Description of the Invention
[018] Reference will now be made in detail to the description of the present subject matter, one or more examples of which are shown in figures. Each example is provided to explain the subject matter and not a limitation. Various changes and modifications obvious to one skilled in the art to which the invention pertains are deemed to be within the spirit, scope and contemplation of the invention.
[019] Before describing in detail embodiments that are in accordance with the present invention, it should be observed that the embodiments reside primarily in combinations of system for twin target stereotactic system with a phantom base to simulate the target and determine the target's accuracy in vitro.
[020] According to an embodiment, the invention discloses a stereotactic system configured for simultaneously identifying two target focusing points. The system includes a stereotactic frame having two separate hemi-arc system symmetrically arranged in the stereotactic frame. The system also has a plurality of target guides, wherein each hemi-arc system has a target guide movably coupled to the hemi-arc system. The system further has two localizer plate with embedded fiducials. These fiducials in the localizer plate facilitate to determine the co-ordinates of the target. The system also has a phantom frame system. The phantom frame system has a workstation displaying the scan image of a subject along with the target determined using the fiducials and a digital pointer. A phantom pointer on the phantom frame system represents the digital pointer on the workstation. The target is identified using the digital pointer which in turn sets the phantom pointer on to the target. The target is simulated in the target guides by positioning the target guides with respect to the phantom pointer.
[021] According to an embodiment the stereotactic frame is secured to the subject's head using posts and pins. In most of the cases 4 posts and pins are used in order to secure the stereotactic frame on to the subject. The localizer plates are then attached to the stereotactic frame, following which the subject is subjected for a scan (CT or MRI). The stereotactic frame accommodates two separate hemi- arc system at the same time. The presence of two hemi-arc system allows the user to target the brain on either side (right and left) at the same given time. The localizer plates are used to determine the fiducials on the imaging system. The fiducials on the imaging system has been developed in such a way that the user has an idea of the depth of the target based on the co-ordinates. For example a negative target means the target is closer to the skull base.
[022] Once scanning is done after attaching the localizer plates, the result of the scan images is fed into the system. The desired targets are identified and the coordinates are also calculated using the workstation of the system. The trajectory may also be planned for the target. The phantom frame is then linked to the workstation of the phantom frame system. The phantom pointer in the phantom frame represents the target. The phantom pointer is moved to desired target using the co-ordinates obtained. The accuracy may be checked on the workstation, where the tip of the phantom pointer is represented on the subject's image present in the workstation. Further, the hemi-arc assembly is then assembled on the phantom frame to simulate the target for surgery. The accuracy of the target is also checked. Once the simulation is satisfactory, the subject with the frame in situ is shifted to the operating room. The hemi-arc assembly is then attached to the frame. Depending on the indication, if both sides need to be targeted (like in deep brain stimulation surgery) then two arcs are used. If single target is planned then a single arc is assembled and attached to the frame and surgery performed.
[023] Figure 1, 2 and 3 illustrate the different views of stereotactic frame along with the phantom frame in accordance with an embodiment of the invention. The phantom pointer (202) of the phantom frames system (200) represents the position of the digital pointer on the workstation is communicatively coupled to the workstation. The workstation display the scan image of a subject along with the target determined using the fiducials and the digital pointer which represents a point on the scan image. The stereotactic frame attached to the phantom frame has two separate hemi-arch system (104) and (106) respectively. Each hemi-arc system has a target guide (108) and (110) respectively. The target guide (108) is movably coupled to the hemi-arc system (104) and the target guide (110) is movably coupled to the hemi-arc system (106). The phantom pointer (202) represents the position of the digital pointer in the workstation. Once the target is identified in the scan image on left side of the brain, then the target guide (108) on the left hemi-arch (104) is moved with respect to phantom pointer (202) in order to identify the target position on the target guide. Once the target is set on the target guide (108), the target guide (108) is moved in order to achieve an optimal access point. Similarly the target on the scan image on right side of the brain is identified and the digital pointer represents the target which in turn sets the phantom pointer (202). Then the target guide (110) on the left hemi-arch (106) is moved with respect to phantom pointer (202) in order to identify the target position on the target guide. Once the target is set on the target guide (108), the target guide (108) is moved in order to achieve an optimal access point. [024] Thus, the double arc stereotactic frame gives the capability of simultaneous targeting of two targets in real time, thereby reducing the operative time and increasing the precision of the target. In addition the Phantom base is used prior to actual surgery to simulate the precision of the procedure in vivo. The stereotactic co-ordinates can be derived manually from the fiducials displayed on the medical imaging system (CT/MRI Scan) or may be derived from the software.
[025] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others may, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein may be practiced with modification within the spirit and scope of the embodiments as described herein.

Claims

[026] CLAIMS: [027] I Claim:
1. A stereotactic system configured for simultaneously identifying two target focusing points, the stereotactic system comprises:
a) a stereotactic frame with two separate hemi-arc system (104, 106) symmetrically arranged in the frame;
b) a plurality of target guides (108, 110), wherein each hemi-arc system have a target guide movably coupled to the hemi-arc system; c) at least one localizer plate having fiducials, wherein the fiducials in a localizer plate facilitate to identify the depth of a target based on the co-ordinates; and
d) a phantom frame system comprising:
i. a workstation displaying the scan image of a subject along with the target determined using the fiducials and a digital pointer which represents a point on the scan image;
ii. a phantom pointer (202) on the phantom frame represents the digital pointer on the workstation, the target is identified using the digital pointer which in turn sets the phantom pointer on to the target;
wherein the target is simulated in the target guides (108, 110) by positioning the target guides (108, 110) with respect to the phantom pointer (202).
2. The system as claimed in claim 1 wherein the target guides (108, 110) are attuned to achieve an optimal access position to the target by keeping the target intact.
PCT/IB2014/065164 2013-10-09 2014-10-09 System for twin target stereotactic system with a phantom base to simulate the target and determine its accuracy in vitro WO2015052669A1 (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105916463A (en) * 2015-07-02 2016-08-31 贺石生 Detachable-mountable arc-shaped precise positioning equipment
WO2017000538A1 (en) * 2015-07-02 2017-01-05 贺石生 Arc-shaped precise positioning device capable of being assembled and disassembled
CN108201472A (en) * 2016-12-20 2018-06-26 财团法人交大思源基金会 Non-invasive head-mounted stereotaxic auxiliary device
CN109932925A (en) * 2017-12-15 2019-06-25 北京机电工程研究所 Scout some emulation modes more

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995021582A1 (en) * 1994-02-15 1995-08-17 Hussman Karl L Localizer
EP2453249A2 (en) * 2010-11-12 2012-05-16 Imris Inc. Multi element transmit/receive head array coil with removable coil elements

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995021582A1 (en) * 1994-02-15 1995-08-17 Hussman Karl L Localizer
EP2453249A2 (en) * 2010-11-12 2012-05-16 Imris Inc. Multi element transmit/receive head array coil with removable coil elements

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105916463A (en) * 2015-07-02 2016-08-31 贺石生 Detachable-mountable arc-shaped precise positioning equipment
WO2017000538A1 (en) * 2015-07-02 2017-01-05 贺石生 Arc-shaped precise positioning device capable of being assembled and disassembled
CN108201472A (en) * 2016-12-20 2018-06-26 财团法人交大思源基金会 Non-invasive head-mounted stereotaxic auxiliary device
CN108201472B (en) * 2016-12-20 2019-10-18 财团法人交大思源基金会 Non-invasive head-mounted stereotaxic auxiliary device
CN109932925A (en) * 2017-12-15 2019-06-25 北京机电工程研究所 Scout some emulation modes more
CN109932925B (en) * 2017-12-15 2021-12-10 北京机电工程研究所 Multi-scout simulation method

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