WO2007133671A2

WO2007133671A2 - Novel implant device and methods

Info

Publication number: WO2007133671A2
Application number: PCT/US2007/011380
Authority: WO
Inventors: Barton Guthrie
Original assignee: The Uab Research Foundation
Priority date: 2006-05-11
Filing date: 2007-05-11
Publication date: 2007-11-22
Also published as: WO2007133671A3

Abstract

The present disclosure describes a novel implant device comprising a plurality of calibration marks. The calibration marks are placed in a relationship with one another and with a location on the implant device such that the dimensional relationships between each of the calibration marks and the functional interface of the implant device can be determined.

Description

Novel Implant Device and Methods

Inventor: Barton Guthrie

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to and benefit of US provisional application no. 60/799,715, filed on May 11, 2006.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

Not applicable FIELD OF THE DISCLOSURE

The present disclosure relates generally to objects for implantation into a body and methods for accurately determining the location of the object in the body. More specifically, the present disclosure relates to an improved implant device and methods of determining the location of the implant device, or a component thereof, within the body of a subject. BACKGROUND

Existing implant devices are currently used for a wide variety or prevention and treatment protocols for a number of disease states and conditions. The use of implant devices is increasing and the efficacy of such treatment and prevention strategies using such implant devices is also increasing. Implant devices come in a variety of shapes and forms and have a number of different functions depending on the nature of the implant device. In one embodiment, the implant devices comprise a functional interface which interacts with a desired target in the subject. For example, many implant devices are being used to interface with neural tissue of a subject (such an implant device may be referred to as a neuroprosthesis). Such neuroprosthetic devices comprise a functional interface through which the neuroprosthetic device interacts with the target, in this case neural tissue. Such interaction may be to record the electrical, chemical or other activity of the neural tissue, or to stimulate the neural tissue by delivering signals, such as electrical, chemical or other signals, to the neural tissue.

The location of the implant device is important for the efficacy of any treatment or prevention therapy using an implant device (such as, but not limited to, a neuroprosthetic device). In many cases the location of the implant device is a major factor is the success or failure of such treatment or prevention therapies. Generally, an imaging technology is used to determine the location of the implant device, or a component thereof (such as but not limited to a functional interface), within the subject and/or to determine the location of the implant device, or a component thereof (such as but not limited to a functional interface) in relation to the target. Imaging technologies include, but are not limited to, computed tomography (CT) scanners, magnetic resonance imaging (MRI) devices, functional MRI devices and positron emission tomography (PET) scanners.

When the implant device comprises a functional interface that interfaces with a target, such as a neuroprosthetic device, the imaging step may be used to precisely define the location of the functional interface in the subject and/or to precisely define the location of the functional interface in relation to the target. With neuroprosthetic applications, a difference in placement of a millimeter with regard to the implant device, or a component thereof (such as, but not limited to, the functional interface) can completely alter the outcome of the treatment and/or prevention strategies. Therefore, in order to accurately monitor and gauge the outcome of the treatment and/or prevention therapies, the location of the implant device, or a component thereof (such as, but not limited to, the functional interface), in relation to the target must be precisely determined.

However, current imaging technologies are often not capable of determining the location of the implant device, or a component thereof (such as, but not limited to, the functional interface) with the desired precision. For example, for many implant devices the imaging technologies generate an artifact around the implant device or a component thereof (such as, but not limited to, the functional interface) which precludes a determination of the precise location of the implant device or a component thereof (such as, but not limited to, the functional interface) in the subject and/or in relation to a target.

The art is lacking an implant device which allows a precise determination of the location of an implant device or a component thereof (such as, but not limited to, the functional interface) in the subject and/or a precise determination of the location of an implant device or a component thereof (such as, but not limited to, the functional interface) in relation to a target within the subject. The present disclosure provides such and implant device, as well as a method determining the precise location of the implant device. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows one embodiment an exemplary implant device (an electrode in this case) of the present disclosure comprising the calibration marks. DETAILED DESCRIPTION Definitions The following terms shall be understood to have the meanings as set forth below.

The terms "prevention", "prevent", "preventing", "suppression", "suppress" and "suppressing" as used herein refer to a course of action (such as administering an implant device) initiated prior to the onset of a clinical manifestation of a disease state or condition so as to prevent or reduce a clinical manifestation of the disease state or condition. Such preventing and suppressing need not be absolute to be useful.

The terms "treatment", "treat" and "treating" as used herein refers a course of action (such as administering an implant device) initiated after the onset of a clinical manifestation of a disease state or condition so as to eliminate or reduce a clinical manifestation of the disease state or condition. Such treating need not be absolute to be useful. The term "in need of treatment" as used herein refers to a judgment made by a caregiver that a patient requires or will benefit from treatment. This judgment is made based on a variety of factors that are in the realm of a caregiver's expertise, but that includes the knowledge that the patient is ill, or will be ill, as the result of a condition that is treatable by an implant device of the disclosure.

The term "in need of prevention" as used herein refers to a judgment made by a caregiver that a patient requires or will benefit from prevention. This judgment is made based on a variety of factors that are in the realm of a caregiver's expertise, but that includes the knowledge that the patient will be ill or may become ill, as the result of a condition that is preventable by an implant device of the disclosure.

The term "individual", "subject" or "patient" as used herein refers to any animal, including mammals, such as mice, rats, other rodents, rabbits, dogs, cats, swine, cattle, sheep, horses, or primates, and humans. The term may specify male or female or both, or exclude male or female.

The term "location" as used herein refers to a three dimensional location of an object, such as an implant device or a component thereof, such as, but not limited to, the functional interface of an implant device.

The term "target" as used herein refers to a tissue, structure, organ, area or defined location within a subject; the term target should be interpreted broadly and can vary as a function of the implant device used and the disease state or condition under treatment or prevention. The term "implant device" as used herein refers a device that can be implanted, at least partially, within a subject and which comprise a functional interface; exemplary implant devices include, but are not limited to, grids, electrodes, deep brain stimulators, catheters, sensors, chips and other devices.

The term "functional interface" as used herein refers to that part of the implant device which interacts with the target; interaction can include contact of the functional interface with the target. The term "sensor" as used herein refers to an implant device that interacts with a target via non-electrical signals, such as but not limited to, chemical, mechanical, optical, magnetic or thermal signals.

The term "electrode" as used herein refers to an implant device that interacts with a target via electrical signals.

The term "calibration mark" as used herein refers to any device, chemical, substance or alteration incorporated into/onto an object or implant device that can be imaged by an imaging technology without producing an artifact as a result of such imaging; the selection of the calibration mark may vary as a function of the imaging technology used and the selection of the proper calibration mark for a given technology is within the expertise of a person having ordinary skill in the art.

The present disclosure illustrates the teachings contained herein with reference to an implant device. However, the teachings of the present disclosure should not be limited to an implant device. The teachings of the present disclosure are applicable to any object that can be implanted in a body, provided that the object comprises one or more calibration marks and the body is capable of being imaged. Implant Device

The present disclosure describes a novel implant device comprising a plurality of calibration marks. The calibration marks are placed in a relationship with one another and with a location on the implant device such that the dimensional relationships between each of the calibration marks and the functional interface of the implant device can be determined. In one embodiment, each of the calibrations marks is in a defined and known relationship with respect to at least one other calibration mark such that the dimensional relationships between each of the calibration marks are khbwh or can be determined. In a particular embodiment, each of the calibrations marks is in a defined and known relationship with respect to one another. Further, at least one of the calibrations marks are in a defined and known relationship with respect to (i) the functional interface of the implant device, (ii) a defined location on the implant device; or a combination of (i) and (ii) such that the dimensional relationships between each of the calibration marks and the functional interface and/or a defined location on the implant device are known or can be determined. In a particular embodiment, each of the calibrations marks is in a defined and known relationship with respect to (i) the functional interface of the implant device, (ii) a defined location on the implant device; or a combination of (i) and (ii); ^:

The calibration marks are selected such that the calibration marks can be imaged by conventional imaging technologies such that the location of the calibration marks with respect to the functional interface can be determined from an inspection of the image. Since the calibration marks are in a defined and known relationship with one at least one other calibration mark and with (i) the functional interface of the implant device, or (ii) a defined location on the implant device, or a combination of (i) and (ii), the location of the implant device or the functional interface of the implant device can be determined in the subject or in relation to the target based on the location of the calibration marks. Furthermore, the target engaged by the functional interface can also be determined by superimposing the location of the calibration marks and/or the functional interface on an image of the target. The calibration marks allow the reconstruction of the location of the implant device and/or the functional interface of the implant device, which can then be superimposed on an image of the target. The calibration marks may be used to determine the location of the functional interface of the implant device and the target engaged by the functional interface even though the functional interface cannot be imaged directly (due to the creation of imaging artifacts as discussed herein).

The calibration marks are designed so that the calibration marks may be imaged without producing an image artifact when imaged using an imaging technology. Imaging technologies include, but are not limited to, computed tomography (CT) scanners, magnetic resonance imaging (MRI) devices, functional MRI devices and positron emission tomography (PET) scanners. In one embodiment, the calibration marks are manufactured from a substance that does not produce an artifact when imaged using a given imaging technology. One or ordinary skill in the art could select such substances based no the particular imaging technology utilized to image the implant device. The calibration marks may be spots, lines, geometric configurations or other structures as is known in the art and may be generated, at least in part, using such substances. Exemplary substances include, but are not limited to, a contrast agent (both positive and negative contrast agents), a dye, a chemical compound, a metal or a radioactive substance. In addition, the calibration mark may be mechanical deformation (that does not interfere with function of the implant device and/or the functional interface) in the implant device or a specially created or unique structure on the implant device. Combinations of any of the foregoing may also be used. For example, suitable contrast agents include, but are not limited to, paramagnetic agents, Tl -relaxation agents, T2- relaxation agents, diamagnetic agents, superparamagnetic agents, and perfluorochemicals. Specific examples of contrast agents include, but are not limited to, an iron containing compound (such as, but not limited to, ferric chloride and ferric ammonium citrate), gadolinium, mineral oil, oil emulsions, sucrose polyester, gadodiamide and gadoteridol. In one embodiment, an exemplary mechanical deformation is a kink in a wire, an indentation in the implant device or a raised area on the implant device. In one embodiment, the calibration marks are permanent, or substantially permanent when applied to the implant device. By substantially permanent it is meant that the calibration marks will remain capable of being imaged for at least 3 months, for at least 6 months, at least one year, at least 2 years, at least three years or at least 4 years after the implant device is implanted into the subject. By permanent it is meant that the calibration marks will remain capable of being imaged for at least 5 years after the implant device is implanted into the subject. In an alternate embodiment, the calibration marks are not permanent (i.e., transient) when applied to the implant device. By "not permanent" it is meant that the calibration marks will not be capable, of being imaged past 3 months after the implant device is implanted into the subject.

The calibration marks may be arranged in a number of spatial configurations on the implant device.

The calibration marks are placed a sufficient distance from the functional interface or other part of the implant device that may give rise to imaging artifacts such that the calibration marks may be imaged without interference from a component of the implant device. In one embodiment, the calibration marks are placed at least 2-5 millimeters away from the functional interface or other component of the implant device that may give rise to imaging artifacts. In an alternate embodiment, the calibration marks are placed at least 5-8 millimeters away from the functional interface or other component of the implant device that may give rise to imaging artifacts.

FIG. 1 shows an exemplary implant device of the present disclosure with a series of three calibration marks applied to the implant device. In this example, the implant device 2 is an electrode as is known in the art. All features of the implant device 2 have not been illustrated for simplicity, but are understood to be present. The implant device 2 comprises a body 4 on which a plurality of calibration marks designated 6A, 6B and 6C are applied. Each of the calibrations marks 6A₃ 6B and 6C is in a defined and known relationship with respect to at least one other calibration mark such that the dimensional relationships between each of the calibration marks are known or can be determined (illustrated by the distances A, B and C in this example). The implant device 1 further comprises a plurality of functional interfaces designated 8A, 8B and 8C. The functional interfaces 8A, 8B and 8C are in a known relationship to one another (as may be determined from an inspection of the implant device before use) and/or a known position on the implant device. The dimensional relationship between at least one of the calibration marks 6 A, 6B and 6C with respect to at least one of the functional interfaces 8A, 8B and 8C is also known or can be calculated. Therefore, the location of the functional interface of the implant device can be determined based on the location of the calibration marks. Furthermore, the location of the functional interface with respect to the target can also be determined by superimposing the location of the functional interface on an image of the subject which contains the target.

The calculations required to determine the location of the functional interface or the target engaged by the functional interface may be determined manually or may be determined by a computer based program supplied with the dimensional relationships between the calibration marks and the dimensional relationship between at least one of the calibration marks and at least one of the functional interfaces on the implant device. In a specific embodiment, the software driving the imaging device may be programmed to make such calculations.

Therefore, the present disclosure also provides for a method of determining the location of the interface between a target and a functional interface of an implant device, where in the implant device is as provided for in the present disclosure. In one embodiment, the functional interface cannot be directly imaged. In one embodiment of such method, A method of determining in a subject the location of an interface between a target and a functional interface of an implant device where the functional interface of the implant device cannot be directly imaged, said method comprising the steps of: (a) providing the implant device, the implant device comprising a plurality of calibration marks, each of the plurality of calibrations marks being in a defined and known relationship with respect to at least one other calibration mark such that the dimensional relationships between each of the calibration marks are known or can be determined and at least one of the calibrations marks being in a defined and known relationship with respect to (i) the functional interface of the implant device, (ii) a defined location on the implant device, or (iii) a combination of (i) and (ii) such that the dimensional relationships between each of the calibration marks and the functional interface or a defined location on the implant device are known or can be determined; (b) implanting the implant device into the subject; (c) imaging the implant device in the subject; and (d) determining the location of interface between the target and the functional interface based on the location of at least one calibration mark. In a particular embodiment, the implant device is a neuroprosthesis and the target is a neural tissue, such as, but not limited to, the brain, the eye, the ear, or the spinal cord, an area on the foregoing or a predetermined location on the foregoing.

The present disclosure describes a novel implant device and the use of a novel implant device to treat and/or prevent a variety of disease states and conditions. The present disclosure provides for methods to treat and/or prevent diseases or conditions in a subject in need of such treatment and/or prevention where the disease state or conditions is characterized by an abnormal characteristic in a target in the subject (as compared to a subject without the disease state or condition) wherein the abnormal characteristic can be treated or prevented by a signal delivered by the implant device. The signal may be chemical, mechanical, optical, magnetic, thermal, electrical or a combination of the foregoing.

The method of treatment comprises the steps of identifying a subject in need of such treatment and initiating in said subject a treatment regimen comprising implanting an implant device of the present disclosure in the subject such that a functional interface of the implant device interfaces with the target and delivers a signal to the target. The signal may be chemical, mechanical, optical, magnetic, thermal, electrical or a combination of the foregoing. Due to the novel ability to determine the location of the implant device and/or the functional interface of the implant device in the subject and/or in relationship to the target, the treatment methods of the present disclosure allow for improved treatment of the disease state or condition. In one embodiment, an exemplary disease state or condition is epilepsy, blindness, deafness or paralysis. Other disease states and conditions may also be treated as would be obvious to one of ordinary skill in the art. The method of prevention comprises the steps of identifying a subject in need of such prevention and initiating in said subject a prevention regimen comprising implanting an implant device of the present disclosure in the subject such that a functional interface of the implant device interfaces with the target and delivers a signal to the target. The signal may be chemical, mechanical, optical, magnetic, thermal, electrical or a combination of the foregoing. Due to the novel ability to determine the location of the implant device and/or the functional interface of the implant device in the subject and/or in relationship to the target, the prevention methods of the present disclosure allow for improved prevention of the disease state or condition. In one embodiment, an exemplary disease state or condition is epilepsy, blindness, deafness or paralysis. Other disease states and conditions may also be treated as would be obvious to one of ordinary skill in the art.

The foregoing description illustrates and describes the methods and other teachings of the present disclosure. Additionally, the disclosure shows and describes only certain embodiments of the methods and other teachings disclosed, but, as mentioned above, it is to be understood that the teachings of the present disclosure are capable of use in various other combinations, modifications, and environments and is capable of changes or modifications within the scope of the teachings as expressed herein, commensurate with the skill and/or knowledge of a person having ordinary skill in the relevant art. The embodiments described hereinabove are further intended to explain best modes known of practicing the methods and other teachings of the present disclosure and to enable others skilled in the art to utilize the teachings of the present disclosure in such, or other, embodiments and with the various modifications required by the particular applications or uses. Accordingly, the methods and other teachings of the present disclosure are not intended to limit the exact embodiments and examples disclosed herein. All references cited herein are incorporated by reference as if fully set forth in this disclosure.

Claims

CLAIMSWhat is claimed:

1. An implant device for use with a subject, the implant device comprising a functional interface for interfacing with a target in the subject and a plurality of calibration marks, each of the plurality of calibrations marks being in a defined and known relationship with respect to at least one other calibration mark such that the dimensional relationships between each of the calibration marks are known or can be determined and at least one of the calibrations marks being in a defined and known relationship with respect to (i) the functional interface of the implant device, (ii) a defined location on the implant device, or (iii) a combination of (i) and (ii) such that the dimensional relationships between each of the calibration marks and the functional interface or a defined location on the implant device are known or can be determined, such that the location of the implant device or the functional interface can be determined in a subject or the location of the implant device or the functional interface can be determined in relation to the target within the subject.

2. The implant device of claim 1 wherein each of the calibrations marks is in a defined and known relationship with respect to one another.

3. The implant device of claim 1 wherein each of the calibrations marks is in a defined and known relationship with respect to (i) the functional interface of the implant device, (ii) a defined location on the implant device, or (iii) a combination of (i) and (ii).

4. The implant device of claim 1 wherein the calibration marks may be imaged without producing an image artifact.

5. The implant device of claim 1 where the calibration marks are manufactured from a material that does not create an image artifact on imaging of the implant device, said materials being selected from the group consisting of a positive contrast agent, a negative contrast agent, a dye, a chemical compound, a metal and a radioactive substance

6. The implant device of claim 1 where the calibration mark is a mechanical deformation, a specially created structure on the implant device or a unique structure on the implant device.

7. The implant device of claim 5 where the contrast agent is a paramagnetic agent, a Tl- relaxation agent, a T2-relaxation agent, a diamagnetic agent, a superparamagnetic agent, a perfluorochemical or a combination of the foregoing.

8. The implant device of claim 5 where the contrast agent is an iron containing compound, gadolinium, mineral oil, oil emulsions, sucrose polyester, gadodiamide, gadoteridol or a combination of the foregoing.

9. The implant device of claim 8 where the iron containing compound is ferric chloride, ferric ammonium citrate or a combination of the foregoing.

10. The implant device of claim 6 wherein the mechanical deformation is a kink in a wire, an indentation on the implant device or a raised area on the implant device.

11. The implant device of claim 1 wherein the calibration marks remain capable of being imaged for at least 3 months, for at least 6 months, for at least one year, for at least 2 years, for at least three years or for at least 4 years after the implant device is implanted into the subject.

12. The implant device of claim 1 wherein the calibration marks remain capable of being imaged for at least 5 years after the implant device is implanted into the subject.

13. The implant device of claim 1 wherein the calibration marks will not be capable of being imaged past 3 months after the implant device is implanted into the subject.

14. calibration marks may be arranged in a number of spatial configurations on the implant device

15. The implant device of claim 1 wherein the calibration marks are placed a sufficient distance from the functional interface or other part of the implant device that may give rise to imaging artifacts such that the calibration marks may be imaged without interference from a component of the implant device

16. The implant device of claim 1 wherein the calibration marks are placed 2-5 millimeters away from the functional interface or other component of the implant device that may give rise to imaging artifacts.

17. The implant device of claim 1 wherein the calibration marks are placed 5-8 millimeters away from the functional interface or other component of the implant device that may give rise to imaging artifacts.

18. The implant device of claim 1 wherein the implant device is a neuroprosthesis and the target is a neural tissue.

19. A method of determining in a subject the location of an interface between a target and a functional interface of an implant device where the functional interface of the implant device cannot be directly imaged, said method comprising the steps of:

(a) providing the implant device, the implant device comprising a plurality of calibration marks, each of the plurality of calibrations marks being in a defined and known relationship with respect to at least one other calibration mark such that the dimensional relationships between each of the calibration marks are known or can be determined and at least one of the calibrations marks being in a defined and known relationship with respect to (i) the functional interface of the implant device, (ii) a defined location on the implant device, or (iii) a combination of (i) and (ii) such that the dimensional relationships between each of the calibration marks and the functional interface or a defined location on the implant device are known or can be determined; (b) implanting the implant device into the subject;

(c) imaging the implant device in the subject; and (d) determining the location of interface between the target and the functional interface based on the location of at least one calibration mark.

20. The method of claim 19 where the determining is accomplished manually or with the aid of an algorithm.

21. The implant device of claim 19 wherein each of the calibrations marks is in a defined and known relationship with respect to one another.

22. The implant device of claim 19 wherein each of the calibrations marks is in a defined and known relationship with respect to (i) the functional interface of the implant device, (ii) a defined location on the implant device, or (iii) a combination of (i) and (ii).

23. The implant device of claim 19 wherein the calibration marks may be imaged without producing an image artifact.

24. The implant device of claim 19 where the calibration marks are manufactured from a material that does not create an image artifact on imaging of the implant device, said materials being selected from the group consisting of a positive contrast agent, a negative contrast agent, a dye, a chemical compound, a metal and a radioactive substance

25. The implant device of claim 19 where the calibration mark is a mechanical deformation, a specially created structure on the implant device or a unique structure on the implant device.

26. The implant device of claim 24 where the contrast agent is a paramagnetic agent, a Tl - relaxation agent, a T2-relaxation agent, a diamagnetic agent, a superparamagnetic agent, a perfluorochemical or a combination of the foregoing.

27. The implant device of claim 24 where the contrast agent is an iron containing compound, gadolinium, mineral oil, oil emulsions, sucrose polyester, gadodiamide, gadoteridol or a combination of the foregoing.

28. The implant device of claim 27 where the iron containing compound is ferric chloride, ferric ammonium citrate or a combination of the foregoing.

29. The implant device of claim 25 wherein the mechanical deformation is a kink in a wire, an indentation on the implant device or a raised area on the implant device.

30. The implant device of claim 19 wherein the calibration marks remain capable of being imaged for at least 3 months, for at least 6 months, for at least one year, for at least 2 years, for at least three years or for at least 4 years after the implant device is implanted into the subject.

31. The implant device of claim 19 wherein the calibration marks remain capable of being imaged for at least 5 years after the implant device is implanted into the subject.

32. The implant device of claim 19 wherein the calibration marks will not be capable of being imaged past 3 months after the implant device is implanted into the subject.

33. calibration marks may be arranged in a number of spatial configurations on the implant device

34. The implant device of claim 19 wherein the calibration marks are placed a sufficient distance from the functional interface or other part of the implant device that may give rise to imaging artifacts such that the calibration marks may be imaged without interference from a component of the implant device

35. The implant device of claim 19 wherein the calibration marks are placed 2-5 millimeters away from the functional interface or other component of the implant device that may give rise to imaging artifacts.

36. The implant device of claim 19 wherein the calibration marks are placed 5-8 millimeters away from the functional interface or other component of the implant device that may give rise to imaging artifacts.

37. The implant device of claim 19 wherein the implant device is a neuroprosthesis and the target is a neural tissue.