Endoscopy method and apparatus

Abstract

The present disclosure provides an endoscopic device and related methods. The device may include a steerable tool having a first flexible tube concentrically nested within a second flexible tube. The device may include an end cap disposed on the steerable tool, an image sensor disposed on the end cap, and one or more light sources disposed on the end cap. The device may be configured to access a region within a patient's middle ear cavity. Accordingly, the device may further include a flexible tube and a pre-curved rigid tube, wherein the steerable tool may extend from the flexible tube and the flexible tube may extend from the rigid tube, thereby enabling the device to be deployed to access the middle ear.

Description

[Technical Field]

[0001] STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT This invention was made with government support under Grant No. 1R44DC019894 awarded by the National Institutes of Health (NIH). The U.S. government has certain rights in this invention.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS This application is a non-provisional application and claims priority to U.S. Provisional Patent Application No. 63 / 419,836, filed October 27, 2022, entitled "METHOD AND APPARATUS FOR OTOLOGIC ENDOSCOPY," which is incorporated herein by reference in its entirety.

[0003] The present disclosure relates generally to endoscopic surgical and / or diagnostic apparatus and methods, and more particularly to deploying endoscopic devices to non-surgically access a patient's middle ear cavity (or particularly a region within the middle ear cavity). [Background technology]

[0004] Approximately 16.4 million people in the United States develop middle ear disease each year, many of whom suffer from clinically relevant hearing loss. One such disease is cholesteatoma, an infiltrative, aggressive, benign tumor that typically arises within the middle ear cavity and slowly and irreversibly erodes critical structures responsible for sound transmission. Because cholesteatoma is recurrent, staged second-look surveillance procedures are necessary to definitively rule out recurrence after one or more surgeries to address the initial diagnosis, resulting in 84,000 cholesteatoma surgeries performed annually in the United States.

[0005] Diagnosis of middle ear disease, and particularly cholesteatoma, is challenging because the disease originates behind the tympanic membrane. External symptoms do not provide a clear diagnosis, and external noninvasive imaging (e.g., CT, MRI, etc.) cannot distinguish cholesteatoma from the surrounding tissues of the middle ear cavity. Therefore, direct visual examination is essential to accurately and comprehensively diagnose middle ear disease and to rule out recurrence beyond clinical doubt.

[0006] The current standard treatment for cholesteatoma involves surgically repositioning the tympanic membrane and ossicular chain (the small bones in the middle ear that mechanically connect the tympanic membrane to the inner ear for sound transmission) to create a hole through the ear canal into the middle ear cavity, allowing visualization of the tissues within the middle ear cavity. After surveillance and / or any surgical procedures within the middle ear cavity, the surgeon reconstructs the ossicular chain and repairs the tympanic membrane. While such surgical procedures are necessary for all surgical procedures that provide a means for cholesteatoma removal (which is accomplished by scraping the inner surface of the middle ear), it would be useful to obtain a definitive diagnosis before surgery (e.g., without the invasive procedures mentioned above), which is currently not possible, for example, with conventional endoscopic systems. Even more importantly, patients typically undergo a second-look surveillance one year after the initial surgery to check for recurrence, since if even a small fragment of cholesteatoma is left behind during the initial surgery, the cholesteatoma will regrow.

[0007] Furthermore, conventional endoscopic systems generally (and not just in the specific context of otologic procedures) are characterized by a variety of problems related to the maneuverability of the endoscopic device, size limitations that prevent the use of advanced imaging and illumination components, etc., which limit the effectiveness of such endoscopes' operation or require invasive surgical procedures.

[0008] Thus, there is a need for improved devices and methods for endoscopic procedures, particularly in the otological context of accessing the middle ear. Summary of the Invention [Means for solving the problem]

[0009] This Summary is provided to introduce some concepts in a simplified form that are more fully described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0010] One aspect of the present disclosure relates to an endoscopic device. The device may include a steerable tool having a first flexible tube concentrically nested within a second flexible tube. The device may further include an image sensor disposed on the steerable tool and one or more light sources disposed on the steerable tool. For example, the image sensor may be a digital complementary metal-oxide semiconductor (CMOS) image sensor. In some embodiments, an end cap is disposed on the steerable tool, with the image sensor and one or more light sources disposed on the end cap. The first flexible tube may include a first deflectable portion, and the second flexible tube may include a second deflectable portion. The first and second deflectable portions may be selectively weakened portions of the first and second flexible tubes that are angularly oriented in directions offset from each other by an angle of 180 degrees or less relative to a longitudinal axis of the steerable tool. For example, the first and second deflectable portions may face in opposite directions relative to the longitudinal axis of the steerable tool. Thus, the steerable tool may be actuable (e.g., configured to be actuated, capable of being actuated, etc.) to form a bend by axially translating the first flexible tube relative to the second flexible tube. Alternatively, in some embodiments, the steerable tool is actuable to form a bend by axially translating the second flexible tube relative to the first flexible tube. In other embodiments, the steerable tool is actuable to form a bend by any relative axial translation between the first and second flexible tubes, including translation of the first flexible tube, translation of the second flexible tube, or translation of both flexible tubes.

[0011] Another aspect of the present disclosure relates to another endoscopic device that may include the steerable tool described above. The device may further include a third flexible tube, wherein the steerable tool may be disposed within the third flexible tube and may be axially movable relative to the third flexible tube. The device may further include a rigid tube, wherein the third flexible tube may be disposed within the rigid tube and may be axially movable relative to the rigid tube.

[0012] Another aspect of the present disclosure relates to a method of accessing a region within a patient's middle-ear cavity, the method may include providing the steerable tool described above and positioning at least a portion of a rigid tube within a nasal passageway, the nasal passageway communicating with the middle-ear cavity via a Eustachian tube between the nasal passageway and the middle-ear cavity. The method may further include extending a third flexible tube from the lumen of the rigid tube, the third flexible tube having at least a portion protruding from an opening formed by a distal end of the rigid tube and the distal end of the third flexible tube positioned along the Eustachian tube toward the middle-ear cavity. The method may further include extending a steerable tool from the lumen of the third flexible tube, wherein at least a portion of the steerable tool protrudes from an opening formed by the distal end of the third flexible tube and wherein the distal end of the steerable tool is positioned within the middle-ear cavity. The method may further include actuating the steerable tool to form a bend, wherein the distal end of the steerable tool is steered toward the region within the middle-ear cavity.

[0013] Various other objects, advantages and features of the present disclosure will become readily apparent to those skilled in the art upon review of the following drawings and description of the preferred embodiment. [Brief explanation of the drawings]

[0014] [Figure 1]FIG. 1 is a perspective view of a tube assembly for an endoscopic device, according to some embodiments of the present disclosure. [Figure 2] 1 is a perspective view of an image sensor assembly according to some embodiments of the present disclosure. FIG. [Figure 3] FIG. 1 is a detailed perspective view of an image sensor assembly according to some embodiments of the present disclosure. [Figure 4A] 1 is a perspective schematic diagram illustrating a first portion of a method for assembling a tube assembly for an endoscopic device, according to some embodiments of the present disclosure. [Figure 4B] 10 is a perspective schematic view illustrating a second portion of a method for assembling a tube assembly for an endoscopic device according to some embodiments of the present disclosure. [Figure 5A] 1 is a side cross-sectional view of a tube assembly for an endoscopic device according to some embodiments of the present disclosure. [Figure 5B] 1 is a side cross-sectional view of a tube assembly for an endoscopic device according to some embodiments of the present disclosure. [Figure 5C] FIG. 1 is a perspective view of a tube assembly for an endoscopic device, according to some embodiments of the present disclosure. [Figure 6A] 1 is a perspective view of an embodiment of a first flexible tube and a second flexible tube of a steerable tool, according to some embodiments of the present disclosure. FIG. [Figure 6B] FIG. 6B is a perspective view of the first flexible tube and the second flexible tube of FIG. 6A assembled to form a steerable tool, according to some embodiments of the present disclosure. [Figure 6C] FIG. 6C is a perspective view of the assembled steerable tool of FIG. 6B actuated to form a bend in a first direction, according to some embodiments of the present disclosure. [Figure 6D] FIG. 6C is a perspective view of the assembled steerable tool of FIG. 6B being actuated to form a bend in a second direction different from the first direction of FIG. 6C according to some embodiments of the present disclosure. [Figure 6E] FIG. 1 is a perspective view of a tube assembly being actuated to form a bend in a first direction, according to some embodiments of the present disclosure. [Figure 6F]6E being actuated to form a bend in a second direction different from the first direction of FIG. 6E, according to some embodiments of the present disclosure. FIG. [Figure 7A] 1A and 1B are side views of first and second flexible tubes for a steerable tool according to some embodiments of the present disclosure. [Figure 7B] 1A and 1B are side views of first and second flexible tubes for a steerable tool according to some embodiments of the present disclosure. [Figure 7C] 1A and 1B are side views of first and second flexible tubes for a steerable tool according to some embodiments of the present disclosure. [Figure 8A] 12 is a perspective view of a user interface of an endoscopic device actuating a steerable tool of the endoscopic device to form a bend in a first direction, according to some embodiments of the present disclosure. FIG. [Figure 8B] FIG. 8B is a detailed perspective view of the steerable tool of FIG. 8A according to some embodiments of the present disclosure. [Figure 8C] FIG. 8B is a perspective view of the user interface of the endoscopic device of FIG. 8A actuating the steerable tool of FIG. 8A to form a bend in a second direction different from the first direction of FIG. 8A, according to some embodiments of the present disclosure. [Figure 8D] FIG. 8D is a detailed perspective view of the steerable tool of FIG. 8C according to some embodiments of the present disclosure. [Figure 8E] 1 is a cross-sectional view of a user interface of an endoscopic device coupled to a tube assembly of the endoscopic device, according to some embodiments of the present disclosure. [Figure 9] FIG. 1 is a perspective view of an endoscopic device with a tube assembly coupled to a user interface, the user interface coupled to a control unit, according to some embodiments of the present disclosure. [Figure 10] 1 is a schematic diagram of a tube assembly for an endoscopic device for accessing the middle ear, according to some embodiments of the present disclosure. [Figure 11] FIG. 11 is a detailed perspective view of the tube assembly of FIG. 10 being manipulated to access the middle ear cavity, according to some embodiments of the present disclosure. [Figure 12] FIG. 11 is an exploded view of the tube assembly of FIG. 10 according to some embodiments of the present disclosure. [Figure 13] 11 is a schematic diagram of a rigid tube of the tube assembly of FIG. 10 interacting with the nasal passages during a first stage deployment of the device of FIG. 10, according to some embodiments of the present disclosure. [Figure 14] 11 is a schematic diagram of the tube assembly of FIG. 10 interacting with the Eustachian tube during a second stage deployment of the device of FIG. 10 , according to some embodiments of the present disclosure. [Figure 15] 11 is a schematic diagram of the tube assembly of FIG. 10 interacting with the middle ear cavity during the third and fourth stages of deployment of the device of FIG. 1 according to some embodiments of the present disclosure. [Figure 16] 11 is a schematic diagram of the tube assembly of FIG. 10 interacting with the middle ear cavity during the third and fourth stages of deployment of the device of FIG. 10 according to some embodiments of the present disclosure. [Figure 17] FIG. 11 is a detailed perspective view of a steerable tool of the tube assembly of FIG. 10 according to some embodiments of the present disclosure. [Figure 18] FIG. 10 is a perspective view of a user interface of an endoscopic device for accessing the middle ear coupled to a tube assembly of the endoscopic device, according to some embodiments of the present disclosure. [Figure 19] FIG. 1 is a perspective view of an endoscopic device for accessing the middle ear, with a tube assembly coupled to a user interface, and the user interface coupled to a control unit, according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0015] While the following provides detailed descriptions of making and using various embodiments of the invention, it should be understood that the invention provides many applicable inventive concepts that can be embodied in a variety of specific contexts. The specific embodiments described herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention. Those skilled in the art will recognize that there are various equivalents to the specific devices and methods described herein. Such equivalents are considered to be within the scope of the invention and are covered by the claims.

[0016] In the drawings, for the sake of clarity, not all reference numbers are included in every drawing. Furthermore, positional terms such as "upper," "lower," "side," "top," "bottom," etc. refer to the device in the orientation shown in the drawings. As will be appreciated by those skilled in the art, the device may be in other orientations when in use.

[0017] The present invention provides methods and devices for accessing the middle ear cavity of a patient using a diagnostic device. Although generally described in the context of accessing the middle ear cavity of a patient, it should be understood that the devices and methods described herein may be applied in a variety of anatomical environments and situations.

[0018] Provided herein is an endoscopic device (device) 100 that can be advantageously applied in an otological environment for accessing the middle ear. As such, device 100 may be provided as a device operated by a user (e.g., a doctor, surgeon, healthcare provider, some other operator, etc.) in gaining access to the middle ear, as well as in performing various endoscopic procedures.

[0019] Referring now first to FIG. 1 , a device 100 according to some embodiments of the present disclosure is shown. The device 100 may include a tube assembly 10 incorporating a steerable tool 20. As described herein, the steerable tool 20 may be configured as an agonist-antagonist concentric tube manipulator and, therefore, may be actuatable (e.g., configured to be actuated, capable of being actuated, etc.) to form a bend such that a distal end 22 of the steerable tool 20 is steered toward an anatomical region (e.g., a surgical site). For example, the steerable tool 20 may include a nested concentric tube structure in which a first flexible tube 28 is nested (e.g., concentrically disposed) within a second flexible tube 23. Each flexible tube, in some applications, includes a rigid portion along its longitudinal length and a flexible portion along its longitudinal length. In another embodiment, each flexible tube is rigid along its entire length except for a flexible region at or near the distal end of the tube. Thus, each flexible tube is flexible in that it includes a flexible portion. As described in more detail below, to employ a concentric agonist-antagonist actuation scheme, a portion of each of the first and second flexible tubes 28, 23 may be configured with asymmetric flexibility characteristics. In some embodiments, the tube assembly 10 further includes an image sensor assembly 102. At least a portion of the image sensor assembly 102 may be disposed within the steerable tool 20.

[0020] As described in more detail below, one or more optical devices (e.g., an image sensor, one or more light sources, etc.) of the image sensor assembly 102 may be located at or near the distal end 22 of the steerable tool. Accordingly, the steerable tool 20 may be configured to facilitate precise navigation of such optical devices toward an anatomical region within a patient once the tube assembly 10 is inserted into the patient. Thus, as described herein, the apparatus 100 may be configured to access and perform surveillance within various anatomical regions, cavities, and structures, depending on the implementation.

[0021] 2, image sensor assembly 102 is shown in detail, according to some embodiments of the present disclosure. In some embodiments, image sensor assembly 102 further includes wiring 112. As described in more detail below, wiring 112 may be configured to transmit power and / or data to support one or more optical elements of image sensor assembly 102, which may be located at or near distal end 109 of image sensor assembly 102.

[0022] 3 , the distal end 106 of the image sensor assembly 102 is shown in detail, according to some embodiments of the present disclosure. As described above with respect to FIG. 2 , the wiring 112 of the image sensor assembly 102 may support one or more optical elements. Such optical elements may include an image sensor 114 and / or one or more light sources 116. The image sensor 114 and / or the one or more light sources 116 may be disposed at or near the distal end 109 of the image sensor assembly 102 and may be in electrical communication with the wiring 112. In other words, the image sensor 114 may be disposed on the steerable tool 20, and the one or more light sources 116 may be disposed on the steerable tool 20.

[0023] In some embodiments, the one or more light sources 116 and the image sensor 114 are at least partially housed within an end cap 118. For example, the end cap 118 may be configured to spatially locate and mechanically secure the image sensor 114, the one or more light sources 116, and the terminations of the wires 112. The end cap 118 may be fabricated by any manufacturing process capable of producing millimeter-scale three-dimensional ("3D") parts (e.g., Swiss machining, micro-injection molding, micro-3D printing, or electrical discharge machining).

[0024] In some embodiments, image sensor 114 is a digital complementary metal-oxide semiconductor ("CMOS") image sensor. Image sensor 114, particularly when implemented as a CMOS image sensor, can enable digital visualization of anatomical regions. For example, image sensor 114 may have a native resolution of 200x200 pixels or greater. In some embodiments, the resolution of image sensor 114 is increased by interpolation using software-based upsampling.

[0025] In some embodiments, wiring 112 includes fiber optic bundle 113 and image sensor wiring bundle 115. Thus, wiring 112 may include signal wiring and power wiring for each of image sensor 114 and one or more light sources 116.

[0026] In some embodiments, the one or more light sources 116 are configured to illuminate the anatomical region and may be housed within the end cap 118. Accordingly, the fiber optic bundle 113 may be a fiber optic illumination bundle. For example, the fiber optic bundle 113, particularly when provided as a fiber optic illumination bundle, may be configured to deliver light from an off-board light source to the one or more light sources 116 such that the one or more light sources 116 illuminate the anatomical region. In another embodiment, the one or more light sources 116 are provided as LEDs disposed within the end cap 118 itself, with the fiber optic bundle 113 extending proximally (e.g., away from the distal end 22) to on-board or off-board circuitry.

[0027] In some embodiments, the image sensor assembly 102 further includes a wire jacket 122. The wire jacket 122 may be configured to provide organization and strain relief for the wires 112. For example, the image sensor wires and fiber optic bundles 115, 113 exit the proximal end of the end cap 118 (e.g., extend away from the distal end 22) and are bundled and encapsulated within the wire jacket 122. The wire jacket 122 may be fabricated from any suitable material, including, but not limited to, a polymeric material (e.g., polyimide, PTFE, fluorinated ethylene propylene, etc.).

[0028] 4A and 4B, an exemplary method of realizing the tube assembly 10 is shown, according to some embodiments of the present disclosure. Referring first to FIG. 4A, the image sensor assembly 102 (specifically the wiring 112) may be fed through the lumen of the first flexible tube 28 (e.g., through the distal end 32 of the first flexible tube 28 shown in FIG. 6A) and disposed within the first flexible tube 28. The first flexible tube 28 (and the image sensor assembly 102) may then be fed through the second flexible tube 23 (e.g., through the proximal end 24 of the second flexible tube 23 shown in FIG. 6A) and the first flexible tube 28 (and the image sensor assembly 102 therein) may be disposed within the second flexible tube 23, thereby disposing the image sensor assembly 102 within the steerable tool 20.

[0029] 4B, the image sensor assembly 102, the first flexible tube 28, and the second flexible tube 23, assembled as described above with respect to FIG. 4A, may be axially adjusted relative to one another to obtain the tube assembly 10 shown in FIG. 1. In some embodiments, the image sensor assembly 102 is secured within the steerable tool 20. As a first example, the end cap 118 may be secured to the first flexible tube 28 and / or the second flexible tube 23 by applying a biocompatible epoxy. As a second example, the end cap 118 may be secured to the first flexible tube 28 and / or the second flexible tube 23 by laser welding. Furthermore, the distal ends of the first and second flexible tubes 28, 23 may be secured to one another at or near their distal ends. For example, as shown in FIGS. 5A-5C, the first and second flexible tubes 28, 23 may be secured to one another near their distal ends by a weld joint 103.

[0030] 5A-5C, various incorporations of an image sensor assembly 102 into a steerable tool 20 are shown, according to various embodiments of the present disclosure. The tube assembly 10 (particularly the distal end of the steerable tool 20) may have an outer diameter of D2. The first flexible tube 28 may have a wall thickness of T1. The second flexible tube 23 may have a wall thickness of T2. As shown in FIG. 3, the end cap 118 may have a diameter of D1.

[0031] 5A, the end cap 118 may be disposed within the second flexible tube 23, with the proximal face of the end cap 118 (e.g., where the wire 112 exits, as shown in FIG. 3) abutting the distal end of the first flexible tube 28. This configuration may provide an advantageous trade-off of increasing the bonding surface area between the end cap 118 and the first and second flexible tubes 28, 23 while minimizing D2 (which in such cases is the sum of D1 and T2). In such a case, the end cap 118 may be adhesively bonded or welded to the inner wall of the second flexible tube 23, and the first and second flexible tubes 28, 23 may be welded to one another at a location proximal to the end cap 118 (resulting in a welded joint as shown). For example, in this case, welding the first and second flexible tubes 28, 23 together to obtain the weld joint 103 can be achieved by machining a window or hole in the second flexible tube 23 and edge welding the periphery of such window or hole to the first flexible tube 28.

[0032] 5B, the end cap 118 may abut the distal tip of each of the first and second flexible tubes 28, 23 and may be secured to the second flexible tube 23. This configuration may provide an advantageous overall minimization of D2 (in such a case, D2 is equal to or approximately equal to D1). For example, in such a case, D2 may be limited only by (or, in other words, only need be comparable in size to) the size of the end cap 118 itself (or, in other words, the size of the image sensor 114 and / or one or more light sources 116 themselves).

[0033] 5C, an end cap 118 may be disposed within the first flexible tube 28. In such a case, the end cap 118 may be adhesively or laser welded to the inner wall of the first flexible tube 28. The first and second flexible tubes 28, 23 may then be welded to each other at their distal ends (resulting in the weld joint 103 shown). As a first example, the distal ends of the first and second flexible tubes 28, 23 may be welded to each other using the window or hole method described above with respect to FIG. 18A. As a second example, the distal ends of the first and second flexible tubes 28, 23 may be welded to each other by slightly offsetting the second flexible tube 23 proximally relative to the first flexible tube 28 and performing a fillet weld around the distal edge of the second flexible tube 23. As a third example, the distal ends of the first and second flexible tubes 28, 23 may be welded together by flush positioning the distal ends of the first and second flexible tubes 28, 23 and edge-welding the first and second flexible tubes 28, 23 together. This configuration may advantageously facilitate assembly. In such a case, D2 may be equal to the sum of D1, T1, and T2. In other embodiments, the distal ends of the first and second flexible tubes 28, 23 may be joined with any suitable fastener or any suitable fastening method to provide a connection therebetween.

[0034] 6A-6F, steerable tool 20 according to various embodiments of the present disclosure are shown in detail. In some embodiments, as described above with respect to FIGS. 5A-5C, first and second flexible tubes 28, 23 are connected or secured to one another (e.g., by welding or adhesive) at or around distal end 22 of steerable tool 20 (e.g., at the distal ends of first and second flexible tubes 28, 23). First flexible tube 28 and second flexible tube 23 may be fabricated from any suitable material, including, but not limited to, nitinol, stainless steel, and plastic / polymer. In some embodiments, first flexible tube 28 and second flexible tube 23 are laser cut from hypodermic tubing.

[0035] The pre-configured state of the steerable tool 20 may be the straight tube configuration shown in FIG. 6B. For example, the illustrated steerable tool 20 may be provided by positioning the first flexible tube 28 relative to the second flexible tube 23 such that the first flexible tube 28 is concentrically nested within the second flexible tube 23 and is at least partially axially aligned with the second flexible tube 23. The steerable tool 20 may be configured to be actuatable to bend in opposite directions, as shown in FIGS. 6C-6F. In other words, the steerable tool 20 may be configured to bend in a single plane. Alternatively, in another embodiment, the steerable tool 20 may be configured to bend along a three-dimensional curved arc.

[0036] Configuring the inner and outer steerable tool tubes 28, 23 to employ the aforementioned concentric agonist-antagonist actuation scheme can be achieved by creating deflectable portions (e.g., flexible portions, selectively weakened portions, etc.) in each of the first and second flexible tubes 28, 23 that provide a region of relatively low stiffness (e.g., a flexible “spine” of material) thereon. Thus, the first flexible tube 28 may include a first deflectable portion 31 and a first tubular sidewall portion 30 extending between the distal end 32 and the proximal end 29. Similarly, the second flexible tube 23 may include a second deflectable portion 26 and a second tubular sidewall portion 27 extending between the distal end 25 and the proximal end 24, thereby forming a flexible portion of the second flexible tube 23.

[0037] To provide the first and second deflectable portions 31, 26, each of the first and second flexible tubes 28, 23 may have material removed (e.g., by laser cutting), thereby forming a flexible "spine" of sidewall material in each of the inner and outer steerable tool tubes 28, 23. With this configuration, the first and second flexible tubes 28, 23 are axially stiff along the first and second tubular sidewall portions 30, 27 (respectively) and axially compliant along the first and second deflectable portions 31, 26 (respectively). The first and second deflectable portions 31, 26 may be configured such that the first and second flexible tubes 28, 23 are characterized by asymmetric elasticity therebetween (e.g., the first elasticity is lower than the second elasticity). This asymmetric resilience allows the first and second flexible tubes 28, 23 to bend (as a result of actuation) along the first and second tubular sidewall portions 30, 27 (respectively).

[0038] In some embodiments, the first and second deflectable portions 31, 26 are obtained by laser machining a slit pattern into the respective sidewalls along a portion of the length of the steerable tool 20 proximal to the distal end 22 of the steerable tool 20. In other words, the first and second flexible tubes 28, 23 may have a first series of cutouts and a second series of cutouts (specifically the first and second deflectable portions 31, 26), respectively, spaced longitudinally along the longitudinal axis 38 of the steerable tool 20, thereby forming respective spines of flexible sidewall material in the first and second flexible tubes 28, 23. In the example configurations of FIGS. 6A-6D , the slit patterns in the first and second flexible tubes 28, 23 are formed by rectangular notches cut into the sidewalls of the tubes. These notches leave the first tubular sidewall portion 30 of the first flexible tube 28 and the second tubular sidewall portion 27 of the second flexible tube 23 intact.

[0039] In another embodiment, as shown in Figures 6E and 6F, the first and second deflectable portions 31, 26 are obtained by laser machining a serpentine profile into each side wall along the portion of the length of the steerable tool 20 proximal to the distal end 22 of the steerable tool 20.

[0040] In some embodiments, the first and second flexible tubes 28, 23 are fixed to one another (e.g., at their distal ends 32, 25) such that the first and second deflectable portions 31, 26 are angularly oriented in directions that are offset from one another by an angle of 180 degrees or less relative to the longitudinal axis 38 (shown in FIGS. 6C and 6D ) of the steerable tool 20. For example, the first and second deflectable portions 31, 26 may be oriented in opposite radial directions relative to the longitudinal axis 38. In another embodiment, the relative angular orientation between the first and second deflectable portions 31, 26 about the longitudinal axis 38 is between 180 degrees and 0 degrees. In some embodiments, the relative angular orientation between the first and second deflectable portions 31, 26 is 180 degrees. In another embodiment, the relative angular orientation between the first and second deflectable portions 31, 26 about the longitudinal axis 38 can be adjusted to any desired relative angular orientation to achieve an optimal bending profile of the distal end 22. Thus, the first and second deflectable portions 31, 26 can be opposed. Because the first and second flexible tubes 28, 23 are connected at the distal end 25 of the second flexible tube 23 and the distal end 32 of the first flexible tube 28 (thereby forming a connection at the distal end 22 of the assembled steerable tool 20), the steerable tool 20 can be actuated to cause or effect bending along its length by applying an axial force (e.g., an axial push and / or pull) to the first flexible tube 28 and / or the second flexible tube 23, or to both flexible tubes sequentially or simultaneously. For example, translating the proximal ends 29, 24 of the first and / or second flexible tubes 28, 23 (respectively) relative to one another causes a bending motion at the distal end 22 of the steerable tool 20 along a bending plane or arc defined by the first and second deflectable portions 31, 26, thereby bidirectionally steering the distal end 22 of the steerable tool 20. Thus, the steerable tool 20 may be actuated to form a bend by axially translating the first flexible tube 28 relative to the second flexible tube 23 (or vice versa).As will be described in more detail below, the direction in which the steerable tool 20 bends may be determined by the push / pull direction of the actuation force applied to the first and / or second flexible tubes 28, 23.

[0041] 6C and 6D, the push / pull directions along which actuation forces are applied are shown relative to the user. Specifically, actuation may be provided by a user interface 60, as will be described in more detail below with reference to FIGS. 8A-8C. Accordingly, an actuation force applied in a "push" direction is applied along the longitudinal axis 38, away from the user (e.g., toward the distal end 22 of the steerable tool 20). Accordingly, an actuation force applied in a "pull" direction is applied along the longitudinal axis 38, toward the user (e.g., away from the distal end 22 of the steerable tool 20). Following this convention, in FIG. 9C, a push force 57 is applied to the first flexible tube 28 (e.g., at its proximal end 29), and a pull force 56 is applied to the second flexible tube 23 (e.g., at its proximal end 24). Similarly, in FIG. 9D, a pulling force 59 is applied to the first flexible tube 28 and a pushing force 58 is applied to the second flexible tube 23 .

[0042] In some embodiments, as generally shown in Figures 6C and 6D, the push / pull forces applied to the first and second flexible tubes 28, 23 can be achieved by applying an axial force to both tubes simultaneously. In other embodiments, as shown in Figures 6E and 6F, the push / pull forces applied to the first and second flexible tubes 28, 23 are relative and therefore can be achieved by applying an axial force to only one of the tubes. Thus, the actuation force applied to the proximal end 29 of the first flexible tube 28 and the proximal end 24 of the second flexible tube 23, as shown in Figures 6C and 6D, can be achieved by applying one of the shown push / pull forces.

[0043] 6E, the steerable tool 20 may be actuated to form a bend such that the distal end 22 is steered along a path 55 by applying a pulling force 59 to the proximal end 29 of the first flexible tube 28 while holding the second flexible tube 23 in a fixed axial position. Alternatively, such movement may be achieved by applying a pushing force 58 to the proximal end 24 of the second flexible tube 23 while holding the first flexible tube 28 in a fixed axial position.

[0044] 6F , the steerable tool 20 may be actuated to form a bend such that the distal end 22 is steered along a path 54 by applying a pushing force 57 to the proximal end 29 of the first flexible tube 28 while holding the second flexible tube 23 in a fixed axial position. Alternatively, such movement may be achieved by applying a pulling force 59 to the proximal end 24 of the second flexible tube 23 while holding the first flexible tube 23 in a fixed axial position.

[0045] 7A-7C, the steerable tool 20 may include two or more segments. For example, the steerable tool 20 may include a steerable segment 71 in a distal region of the steerable tool 20, which may include the deflectable portions 31, 26 of the first and second flexible tubes 28, 23. The steerable segment 71 may thus be controlled by a user as described above.

[0046] In some embodiments, the steerable tool 20 further includes a transmission segment 73 disposed proximally from the steerable segment 71. The transmission segment 73 may be a segment of the steerable tool 20 that connects the steerable segment 71 to the user interface 60, as described in more detail below with respect to Figures 8A-8C. Thus, the transmission segment 73 may be configured to enable the user interface 60 to navigate the distal end 22 of the steerable tool 20 through a path toward an anatomical region within a patient.

[0047] In some embodiments, the transmission section 73 is made from the same piece of tubing as the steerable section 71. In other words, the steerable section 71 and the transmission section 73 may be formed as a single piece of material. In other embodiments, the transmission section 73 is a separate tube that is glued or welded to the steerable section 71.

[0048] 7A , in applications where the path to the anatomical region is essentially straight, the transmission segment 73 may be a rigid, solid tubing. Referring now to FIGS. 7B and 7C , in applications where the path to the anatomical region is more tortuous, the transmission segment 73 may include a flexible segment 75 and a rigid segment 77. The rigid segment 77 may be made of a solid tubing. The rigid segment 77 may be proximal to both the steerable segment 71 and the flexible segment 75 and may serve as a rigid end to which a linear force may be applied (e.g., by the user interface 60) to extend the steerable tool 20 through a path toward the anatomical region. The flexible segment 75 may then be sufficiently flexible to accommodate a tortuous path toward the anatomical region. As a first example, the aforementioned flexibility of the flexible segment 75 may be achieved by a pattern or multiple slots laser-machined into the first and second flexible tubes 28, 23 to reduce their stiffness. As a second example, the aforementioned flexibility of the flexible section 75 may be achieved by including a tube of a more flexible polymer tubing material (e.g., polyimide, PEBAX, nylon, etc.). As a third example, the aforementioned flexibility of the flexible section 75 may be achieved by the same or similar methods used to provide the first and second deflectable portions 31, 26 of the first and second flexible tubes 28, 23, described above. Depending on the implementation, one or both of the flexible section 75 and the rigid section 77 may include braid reinforcement.

[0049] 7B and 7C , the flexible segment 75 may extend over a portion of the length of the transmission segment 73, as shown in FIG. 7B , or may extend over the entire length or nearly the entire length of the transmission segment 73, as shown in FIG. 7C . The slot pattern forming the flexible segment 75 may be constant along the length of the flexible segment or may vary along the length of the flexible segment, depending on the implementation. This variation may be achieved by changing the spacing (e.g., pitch) between successive slot segments or by increasing the arc length (e.g., the length of the resected portion) of each slot around the circumference of the tube. Such variation may be desirable depending on the anatomy being accessed. For example, a more flexible distal portion of the transmission segment 73 may be advantageous for better conforming to the native anatomy being accessed, while a less flexible proximal segment of the transmission segment 73 may be advantageous for easier pushing, torque application, and device control by the user interface 60.

[0050] 8A-8D, device 100 may include a user interface 60 coupled to tube assembly 10, according to some embodiments of the present disclosure. For example, as described above, steerable tool 20 of device 100 may be actuated to form a bend. Such actuation may be ostensibly performed by user interface 60, which houses various controls that a physician or other operator can use to control device 100. As shown, user interface 60 may be configured with a pistol grip design formed by handle 62.

[0051] In some embodiments, a thumb-actuated lever 65 may convert rotational motion (applied by an operator) into linear motion of the tube assembly 10 of the device 100. This rotational motion may be generated by any number of rotary-to-linear mechanical transmissions, including a slider-crank mechanism, a Scotch-yoke mechanism, or a rack-and-pinion mechanism. As a first example, the user interface 60 may be configured such that rotating the lever 65 in a first direction, as shown in FIG. 8A , converts the rotational motion of the lever 65 into linear motion that applies a pulling force 59 to the proximal end 29 of the first flexible tube 28 while holding the second flexible tube 23 in a fixed axial position (as shown in FIGS. 6D and 6E ), thereby actuating the steerable tool 20 to form a bend such that the distal end 22 is steered along a path 55, as shown in FIG. 8B . As a second example, the user interface may be configured such that rotating the lever 65 in a second direction, as shown in Figure 8C, while holding the second flexible tube 23 in a fixed axial position (as shown in Figures 6C and 6F), converts the rotational motion of the lever 65 into linear motion that applies a pushing force 57 to the proximal end 29 of the first flexible tube 28, thereby actuating the steerable tool 20 to form a bend such that the distal end is steered along the path 54, as shown in Figure 8D. In some embodiments, the device includes a mechanical transmission that converts the rotational motion into linear (i.e., axial) translation between the first flexible tube 28 and the second flexible tube 23, thereby actuating the steerable tool 20 to form a bend.

[0052] 8E, a cross-sectional view of a user interface 60 is shown, according to some embodiments of the present disclosure. As shown, the second flexible tube 23 may be fixed to a fixed mount bracket 130 within the handle 62, and the first flexible tube 28 may be attached to a sliding bracket 132 that is part of a larger Scotch yoke transmission mechanism (in the case where the lever 65 acts as a crank). Rotating the lever 65 may cause the Scotch yoke transmission mechanism 134 to actuate the steerable tool 20 so that it forms a bend.

[0053] As a first example, when the lever 65 is rotated counterclockwise, the Scotch yoke transmission 134 can convert the rotation of the lever 65 into a rearward linear motion of the crank pin 136. The crank pin 136 can then apply a rearward force to the slide bracket 132, which can pull and translate the first flexible tube 28 relative to the fixed flexible tube 23. Thus, the slide bracket 132 can apply a pulling force 59 to the proximal end 29 of the first flexible tube 28, actuating the steerable tool 20 to form a bend such that the distal end 22 is steered along the path 55, as shown in FIG. 8B , while the second flexible tube 23 remains in place.

[0054] As a second example, when the lever 65 is rotated clockwise, the Scotch yoke transmission 134 can convert the rotation of the lever 65 into a forward linear motion of the crank pin 136. The crank pin 136 can then apply a forward force to the slide bracket 132, which can push and translate the first flexible tube 28 relative to the fixed second flexible tube 23. Thus, the slide bracket 132 can apply a pushing force 57 to the proximal end 29 of the first flexible tube 28, actuating the steerable tool 20 to form a bend such that the distal end is steered along the path 54, as shown in FIG. 8D , while the second flexible tube 23 remains in place. Of course, as suggested above, the described Scotch yoke mechanism is one of many rotary to linear motion transmission mechanisms that can be used to convert user input force into output that bends the motion of the steerable tool 20.

[0055] 9 , according to some embodiments of the present disclosure, device 100 may further include an external video processing device, such as an off-board processing and control unit (external control unit) 180, in electrical communication with user interface 60. In some embodiments, referring again to FIG. 8E , user interface 60 spatially arranges, mechanically protects, and / or encapsulates the electronic circuitry necessary to condition the signal generated by image sensor 21 before passing it to external control unit 180. For example, user interface 60 may include on-board circuit board 138, which may include memory 140. In some embodiments, memory 140 is on-board programmable read-only memory (e.g., electrically erasable programmable read-only memory (“EEPROM”), etc.), which may be used to store device-specific identifiers or timestamp information associated with device 100, which may be later queried by external control unit 180 to verify the validity of the device. Advantageously, the interaction between the external control unit 180 and the memory 140, as described above, can advantageously prevent device reuse or expiration of the device 100 by applying a lockout period based on this device-specific / time information associated with the device 100. For example, if the device 100 is specified with a specific expiration period (e.g., two years) and the manufacturing date indicated in the factory-written manufacturing timestamp is more than two years old, the external control unit 180 can disable its display port to prevent device 100 from being used beyond its expiration period. In another embodiment, the memory 140 can store a timestamp of when the external control unit 180 was first connected. The external control unit 180 can query this timestamp, compare it to the current date and time, and if a certain amount of time (e.g., 24 hours) has passed, implement a device lockout to prevent device reuse.

[0056] In some embodiments, the user interface 60 includes an LED 142. The LED 142 can generate the illumination necessary for operation of the one or more light sources 116. For example, as described above with respect to FIG. 14 , the wiring 112 can include a fiber optic bundle 113. The LED 142 can then provide illumination to the one or more light sources 116 via the fiber optic bundle 113. The LED 142 can be powered with enough wattage to allow the one or more light sources 116 to adequately illuminate the anatomical region, taking into account heat and light losses along the fiber optic bundle 113. In another embodiment, the illumination necessary for operation of the one or more light sources 116 can be generated from an off-board LED or incandescent bulb housed in the external control unit 180. In such a case, the off-board LED or incandescent bulb can be coupled to the one or more light sources 116 by a fiber optic bundle that passes through the user interface 60 (separately or together with the camera image sensor wiring bundle 115).

[0057] In some embodiments, the user interface 60 further includes a heat sink 144. The heat sink 144 may be sized to ensure sufficient heat dissipation so that the surface temperature of the heat sink 144 (as well as any components or surfaces of the user interface 60 in direct contact with the heat sink 144) does not exceed a specified threshold for safe handheld operation (e.g., 41°C). For example, the LEDs 142 may be mechanically and thermally coupled to the heat sink 144. The heat sink 144 may be attached within the handle 62 of the user interface 60 with fasteners or an epoxy compound having sufficient insulating properties.

[0058] In some embodiments, the user interface 60 includes programmable buttons 144 that can be used to control various image capture functions and video settings associated with the operation of the image sensor 114 (ie, white balance adjustment, automatic gain adjustment).

[0059] In some embodiments, the wiring (which may include or interface with wiring 112 or components thereof) exits the user interface through strain relief 148 and is ultimately terminated at external control unit 180 for further signal conditioning, conversion, and digitization. The connector connecting user interface 60 to external control unit 180 may include a radio frequency identification (RFID) tag that is queried by an RFID reader / antenna in external control unit 180, and a lockout is implemented if a matching RFID tag is not detected. In some embodiments, the wiring exiting user interface 60 is provided with adequate slack to avoid tension during operation of device 100 described herein.

[0060] Depending on the implementation, the external control unit 180 may include one or more of the following: a wired connection to the user interface 60, on-board power conditioning (to convert AC voltage supplied from the power grid to an appropriate DC voltage), video processing and digital conversion circuitry (including, in some embodiments, software-based image interpolation to generate higher resolutions than the native resolution of the image sensor 114), video output to an external monitor, and / or a frame grabber in any number of different formats (HDMI, VGA, DVI, DisplayPort, S-Video, etc.). The external control unit 180 may also include various buttons / control inputs that allow a user to calibrate the image sensor, control the appearance of the video, and / or modify video and image capture parameters (including, but not limited to, device power, lighting brightness, white balance, resolution, auto gain / exposure, image capture and sound recording).

[0061] 14 , the fiber optic bundle 113 may be configured to deliver light from an off-board light source to one or more light sources 116. Such off-board light sources may be housed within the external control unit 180. In such embodiments, the external control unit 180 may include a power source configured to power the image sensor and one or more light sources, including providing appropriate power to the illumination source. The power source may include one or more batteries or any suitable AC or DC power source, such as, but not limited to, an external or internal power interface. Additionally, the external control unit 180 may include an illumination LED or incandescent bulb optically coupled to the one or more light sources 116 by the fiber optic bundle 113.

[0062] In some embodiments, the external control unit 180 includes on-board memory for storing files such as video recordings, image captures, and snapshots taken by a user with the image sensor 114, and means for retrieving such stored files (by writing to an external storage medium such as an external hard disk or SD card, or by serial transfer over a Universal Serial Bus (“USB”) connection). In another embodiment, the external control unit 180 acts as a pass-through to an external video / image capture and storage system (e.g., a frame grabber system) via wired or wireless data transmission. The external control unit 180 may also include indicators that communicate status and fault conditions associated with the device 400 visually (e.g., via status LEDs, pilot lights, etc.) and audibly (e.g., via audible alarms, etc.). As previously mentioned, the external control unit 180 may include an RFID reader / antenna for querying all devices connected to the external control unit 180 to determine compatibility and to enforce lockout if compatibility is not confirmed.

[0063] 10-11 , according to various embodiments of the present disclosure, the device may further be specifically configured to access the middle ear cavity 44 via the Eustachian tube 42 and the nasal passageway 40. For example, using the nasal passageway 40 as an entry point into the patient's body allows at least a portion of the tube assembly 10 (e.g., the distal end 22 of the steerable tool 20) to non-surgically access the middle ear cavity 44 to facilitate diagnosis and surveillance of identifiable middle ear disorders at that location.

[0064] As described above, the steerable tool 20 may be actuable (e.g., controllable, movable, translatable, rotatable) to form a bend (e.g., curve, deflection, etc.) such that the distal end 22 is steered (e.g., deflected) toward one anatomical region or another within the middle ear cavity 44. For example, with reference to FIG. 11 , the distal end 22 can be steered toward a cholesteatoma 49 located within the middle ear cavity 44.

[0065] As will be described in more detail below with respect to FIG. 12 , tube assembly 10 (including steerable tool 20 described above) may be provided as an assembly of three or more concentrically nested telescopic tubes operable to perform multi-stage deployment (as will be described below with respect to FIGS. 13-16 ) to access middle-ear cavity 44. For example, tube assembly 10 may include, in addition to steerable tool 20, rigid tube 12 and third flexible tube 17. As will be described in more detail below, third flexible tube 17 may be a flexible catheter, and rigid tube 12 may be a rigid cannula.

[0066] The methods and devices described herein provide access to the middle ear cavity 44 as shown, which in turn provides access to the middle ear cavity 44 without the drawbacks associated with the conventional surgical process of creating a hole in the ear canal 48 and displacing the tympanic membrane 43 and ossicular chain 41 (including the malleus 45, incus 46, and stapes 47) to access the middle ear cavity 44.

[0067] 12 , an exploded view of a tube assembly 10 configured to access the middle ear is shown, according to some embodiments of the present disclosure. As described above, the tube assembly 10 includes a rigid tube 12, a third flexible tube 17, and a steerable tool 20. The rigid tube 12 and the third flexible tube 17 each include a lumen through which components of the device 100 may be passed. In some embodiments, the steerable tool 20 further includes a lumen through which various components of the device 100 may be passed (e.g., the image sensor assembly 102 described above).

[0068] In some embodiments, to facilitate gradual deployment of the device 100 described herein, the rigid tube 12 includes a lumen extending from the proximal end 13 (shown in FIG. 1 ) to the distal end 16. Similarly, the third flexible tube 17 may include a lumen extending from the proximal end 18 to the distal end 19. The third flexible tube 17 may be disposed within the lumen of the rigid tube 12 and may be axially movable relative to the rigid tube 12 (e.g., along an axis 35 defined by at least a portion of the rigid tube 12), such that at least a portion of the third flexible tube 17 protrudes from an opening formed by the distal end 16 of the rigid tube 12, as shown later in FIG. 14 . Similarly, the steerable tool 20 may be disposed within the lumen of the third flexible tube 17 and may be axially movable relative to the third flexible tube 17, such that at least a portion of the steerable tool 20 protrudes from an opening formed by the distal end 19 of the third flexible tube 17, as shown later in Figures 6 and 7.

[0069] 13, one embodiment of a device 100 configured to access the middle ear is shown, according to some embodiments of the present disclosure. Specifically, FIG. 13 illustrates a first stage of a multi-stage deployment of the tube assembly 10 when configured as described above with respect to FIG. 12. As will be described in more detail below, the first stage may include providing or placing at least a portion of the rigid tube 12 within the nasal passage 40, which communicates with the middle ear cavity 44, with the Eustachian tube 42 sandwiched between the nasal passage 40 and the middle ear cavity 44.

[0070] Thus, in some embodiments, the rigid tube 12 may be inserted into and navigated through the entrance 52 of the Eustachian tube 42. For example, as described in more detail below, the rigid tube 12 may extend (or be positioned) into the entrance 51 of the nasal passage 40 (e.g., a patient's nostril) and extend into the nasal passage 40 until a distal portion of the rigid tube 12 is aligned with the entrance 52 of the Eustachian tube. Thus, the rigid tube 12 may form a nasopharyngeal conduit bridging the entrance 51 of the nasal passage 40 to the entrance 52 of the Eustachian tube 42.

[0071] In some embodiments, rigid tube 12 may have a preformed curve that forms an angle between a first axis defined by the distal portion of rigid tube 12 and a second axis defined by the proximal portion of rigid tube 12. In some embodiments, this angle is an obtuse angle, approximately 110 to approximately 160 degrees, as shown in FIG. 13 . Alternatively, in some embodiments, this angle may be represented as an acute angle of approximately 20 to 70 degrees between the proximal portion of rigid tube 12 and a proximal extension of the longitudinal axis of the distal portion of rigid tube 12 that projects toward the proximal portion of rigid tube 12. In other words, rigid tube 12 includes a pre-curved portion 14 located between distal end 16 and proximal end 13, and rigid tube 12 may include one or more straight (or nearly straight) portions located on either end of pre-curved portion 14. For example, proximal portion 11 (extending between pre-curved portion 14 and proximal end 13) of rigid tube 12 may be straight. Additionally, rigid tube 12 may also include a straight distal portion 15 extending between pre-curved portion 14 and distal end 16. Pre-curved portion 14 of rigid tube 12 may allow a user (e.g., a surgeon, doctor, operator, etc.) to align distal end 16 (and, in some embodiments, distal portion 15) with the axis of Eustachian tube 42 (specifically, where the Eustachian tube forms ostium 52).

[0072] The rigid tube 12 may be made of any suitable material, including, but not limited to, rigid metals commonly used in the manufacture of medical devices (e.g., stainless steel, titanium, etc.) and sufficiently rigid biocompatible polymers. The rigid tube 12 may further include a low-friction inner liner concentrically disposed inside the outer layer of the rigid material. The inner liner may facilitate the extension of the third flexible tube 17 through the lumen of the rigid tube 12. The inner liner may be made of any suitable material, including, but not limited to, polytetrafluoroethylene (PTFE). The rigid tube 12 may further include markings or reference features to assist the user in inserting the rigid tube 12 to the appropriate depth within the nasal passage 40 and / or Eustachian tube 42. The rigid tube 12 may further include a lubricity-enhancing material and / or lubricant disposed on the outer surface of the rigid material layer. Such materials and / or lubricants may include, but are not limited to, a hydrophilic coating, electropolishing, electroplating, and / or a thin film PTFE jacket.

[0073] The rigid tube 12 may have an outer diameter of about 4 millimeters or less for insertion into the nasal passage 40 and may be long enough to extend between the entrance 51 of the nasal passage 40 and the entrance 52 of the Eustachian tube 42. The pre-curved portion 14 may form an angle of about 20 to about 70 degrees between the axis defined by the proximal portion 11 and the distal end 16 (and, in some embodiments, the distal portion 15). Such an angle may allow the rigid tube 12 to accommodate the angle formed between the axis of the Eustachian tube 42 and the sagittal plane defined by the patient's anatomy. In various embodiments, the pre-curved portion 14 defines a compound curve or a series of curves rather than a single, constant curve as generally indicated herein.

[0074] The distal end 16 of the rigid tube 12 may be manufactured from any suitable material, including, but not limited to, a transparent polymeric material (e.g., PTFE), such that the third flexible tube 17 and / or any markings or fiducial features on its surface are visible through the distal end 16. In some embodiments, the distal end 16 may be manufactured to allow for atraumatic contact with the patient (e.g., various surfaces of the nasal passages 40 and / or Eustachian tube 42). For example, the distal end 16 may be manufactured from a softer material, including, but not limited to, PEBAX 70D. Additionally, the distal end 16 may feature a swaged outer diameter to facilitate atraumatic contact while the user aligns the tube assembly 10 with the entrance 52 of the Eustachian tube 42.

[0075] The proximal portion 11 of the rigid tube 12 may terminate in a hub (e.g., hub 68, described in detail below with respect to FIG. 10 ). For example, the hub may be coupled to the proximal portion 11 at the proximal end 13 of the rigid tube 12.

[0076] 14, an embodiment of a device 100 configured to access the middle ear is shown, according to some embodiments of the present disclosure. Specifically, FIG. 14 illustrates a second stage of the multi-stage deployment of the tube assembly 10 described above. As described in more detail below, the second stage may include extending the third flexible tube 17 from the lumen of the rigid tube 12, with at least a portion of the third flexible tube 17 protruding from the opening formed by the distal end of the rigid tube 12, and with the distal end of the third flexible tube 17 positioned along the Eustachian tube 42 toward the middle ear cavity 44.

[0077] Thus, in some embodiments, the third flexible tube 17 extends through the lumen of the rigid tube 12 (e.g., moves axially relative to the lumen), protrudes in the direction 36 from the opening formed by the distal end 16 of the rigid tube 12, and extends along the Eustachian tube 42 from the entrance 52 of the Eustachian tube 42 to the entrance 53 of the middle ear cavity 44.

[0078] The third flexible tube 17 may be a third flexible tube (referred to as a "first" flexible tube to distinguish it from the "second" and "third" flexible tubes that may be included in the steerable tool 20, described below) that is sufficiently flexible to traverse the pre-curved portion 14 of the rigid tube 12 without incurring material yield. In some embodiments, the third flexible tube 17 comprises a tube made of a single flexible material. For example, the single flexible material may be any suitable material, including, but not limited to, latex, silicone, Teflon, and metals laser-cut to reduce the bending stiffness of the material (e.g., Nitinol, stainless steel, titanium, etc.). In another embodiment, the third flexible tube 17 comprises a tube made of two or more layers of dissimilar materials. For example, the third flexible tube 17 may include a lubricious liner layer and a braided material layer to reinforce the integrity of the lubricious liner layer. The lubricious liner layer may be made of any suitable material, including, but not limited to, PTFE. The braid material layer may be made of any suitable material, including, but not limited to, stainless steel, Nitinol, and Kevlar. In such an implementation, the third flexible tube 17 may further include a jacket layer of material disposed around the braid material layer to smooth and protect the surface of the third flexible tube 17 from scratches. The jacket layer may be made of any suitable material, including, but not limited to, nylon, polyimide, and polyether block amide (e.g., PEBAX).

[0079] In some embodiments, the third flexible tube 17 may have an outer diameter of about 3 millimeters or less so that it extends along the Eustachian tube 42 and may have a total length such that it protrudes from the opening formed by the distal end 16 of the rigid tube 12 by about 20 to about 40 millimeters. In other embodiments, the third flexible tube 17 may have any suitable outer diameter that accommodates the anatomical dimensions of a patient, which may vary from patient to patient. In some embodiments, the outer diameter of the third flexible tube 17 is about 1 to about 4 millimeters.

[0080] In some embodiments, the distal end 19 of the third flexible tube 17 may be fabricated from a softer material (than the material comprising the entire body of the third flexible tube 17 described above), thereby allowing for atraumatic contact with the patient (e.g., various surfaces, including the entrance 52 of the Eustachian tube 42, the entrance 53 of the middle ear cavity 44, etc.). Additionally, the distal end 19 may be fabricated from a softer material (e.g., PEBAX 70D) and feature an atraumatic tip with a swaged outer diameter that facilitates lining up with the entrance 53 of the middle ear cavity 44.

[0081] In some embodiments, the third flexible tube 17 may further include a material and / or lubricant disposed on its exterior surface to enhance lubricity. Such materials and / or lubricants may include, but are not limited to, a hydrophilic coating, electropolishing, electroplating, and / or a thin PTFE jacket. The third flexible tube 17 may include a low-friction inner liner (e.g., made of PTFE) to facilitate passage of the steerable tool 20 through the lumen of the third flexible tube 17. In some embodiments, the third flexible tube 17 is printed with markings or reference features at various locations along its length to assist the user in inserting the third flexible tube 17 to the appropriate depth within the Eustachian tube 42 (e.g., to the entrance 53 of the middle ear cavity 44).

[0082] In some embodiments, the third flexible tube 17 may be characterized by a varying bending stiffness (e.g., stiffness modulation) along the length of the third flexible tube 17. For example, it may be advantageous for a proximal section of the third flexible tube 17 (e.g., a region of the third flexible tube 17 near the proximal end 18) to be stiffer to aid in pushability and torque application, while a distal section of the third flexible tube 17 (e.g., a region of the third flexible tube 17 near the distal end 19) to be more flexible and softer (and therefore more able to conform to the pre-curved portion 14 of the rigid tube 12, as well as the Eustachian tube 42).

[0083] In some embodiments, such variation in bending stiffness along the length of the third flexible tube 17 is achieved by increasing or decreasing the density of the braid material along the length of the third flexible tube 17. For example, as described above, the third flexible tube 17 may include layers of braid material, a liner layer, and / or a jacket layer. Such density of the braid material may be considered the number of intersections of the braid material per inch, or intersections per inch ("PIC"). Varying the PIC while holding all other parameters constant (e.g., jacket and / or liner material and thickness, diameter of the third flexible tube 17, etc.) has the effect of varying the bending stiffness of the third flexible tube 17 or its proximal and distal sections.

[0084] In another embodiment, such a variation in bending stiffness along the length of the third flexible tube 17 is achieved by utilizing a higher durometer material as the jacket of the proximal section of the third flexible tube 17 and thermally bonding it to a lower durometer material of the distal section of the third flexible tube 17. In yet another embodiment, such a variation in bending stiffness along the length of the third flexible tube 17 is achieved by nesting the proximal section 80 of the third flexible tube 17 within a thin-walled metal (e.g., stainless steel) hypotube.

[0085] 15 and 16 , one embodiment of a device 100 configured to access the middle ear is shown, according to some embodiments of the present disclosure. Specifically, FIGS. 15 and 16 illustrate the third and fourth stages, respectively, of the multi-stage deployment of the tube assembly 10 described above. The third stage of deployment may include extending the steerable tool 20 from the lumen of the third flexible tube 17, where at least a portion of the steerable tool 20 protrudes from an opening formed by the distal end of the third flexible tube, and the distal end of the steerable tool 20 is positioned within the middle ear cavity 44. The fourth stage of deployment may include actuating the steerable tool 20 to form a bend, where the distal end 22 of the steerable tool 20 is steered toward an anatomical region within the middle ear cavity 44.

[0086] Thus, in some embodiments, the steerable tool 20 extends through the rigid cannula and the lumen of the third flexible tube 17 (e.g., moves axially relative to the lumen) to protrude in direction 37 from an opening formed by the distal end 19 of the third flexible tube 17 and extend into the middle ear cavity 44 through an entrance 53 of the middle ear cavity 44. The steerable tool 20 is then actuated to form a bend as described above, whereby the distal end 22 of the steerable tool 20 is steered in two or more directions to navigate toward an anatomical region within the middle ear cavity 44. For example, FIG. 15 illustrates the distal end 22 being steered in a first circumferential direction 33 relative to an axis 34 defined by the distal end 19 of the third flexible tube 17. As another example, FIG. 16 illustrates the distal end 22 being steered in a second circumferential direction 39 relative to the axis 34.

[0087] 17, a steerable tool 20 according to some embodiments of the present disclosure is shown in detail. As described above, the steerable tool 20 may be actuated to form a bend for steering the distal end 22 of the steerable tool 20. The steerable tool 20 may be flexible enough to traverse the pre-curved portion 14 of the rigid tube 12 without incurring material loss. The steerable tool 20 may have an outer diameter of 1.6 millimeters or less to fit through the lumen of the third flexible tube 17. In another embodiment, the outer diameter of the steerable tool 20 in the region configured to enter and / or fit through the third flexible tube 17 is about 1 to about 2 millimeters. In another embodiment, the outer diameter of the steerable tool 20 at the region configured to enter and / or pass through the third flexible tube 17 may be sized to correspond to the anatomical dimensions of the Eustachian tube, which may vary from patient to patient. In some embodiments, the steerable tool 20 may be long enough to protrude from the opening formed by the distal end 19 of the third flexible tube 17 by about 20 to about 30 millimeters, thereby allowing the distal end 22 of the steerable tool to be steerable into a range of dimensions defined by the middle-ear cavity 44.

[0088] As mentioned above, the steerable tool 20 may include two or more sections, including the steerable section 71 and the transmission section 73, which may include a flexible section 75 and a rigid section 77. In some embodiments, particularly in middle-ear access situations, the conformability of the flexible section 75 may be achieved by a pattern engineered into the medical tubing or by constructing the flexible section 75 using a material that is more flexible / conformable than the rigid section 77. For example, the flexible section 75 may be bend-compliant to allow the steerable tool 20 to thread through the pre-curved portion 14 of the rigid tube 12. Additionally, the rigid section 77 may be used as a rigid end to which a linear force may be applied to extend the steerable tool 20 through the lumen of the third flexible tube 17 and into the middle-ear cavity 44. In some embodiments, the entire steerable tool 20 may be long enough that the rigid section 77 is movably positioned between the proximal portion 11 of the rigid tube 12 and any retainer or linear slider featured on the actuator (e.g., the user interface 60 described above) used to extend the steerable tool 20. That is, the rigid section 77 may be movably positioned within the device 100 without being required to navigate the pre-curved portion 14 of the rigid tube 12.

[0089] In some embodiments of the device 100 configured to access the middle ear, the tube assembly 10 includes an image sensor assembly 102 disposed within the steerable tool 20, as described above. Alternatively, as shown, the steerable tool 20 may include a tool assembly 70 disposed at or about the distal end 22 of the steerable tool 20.

[0090] In some embodiments, tool assembly 70 may include a digital image and / or video sensor 72 mounted to distal end 22. Image and / or video sensor 72 may capture images of the surrounding area of ​​middle ear cavity 44 (e.g., cholesteatoma 49 shown with respect to FIG. 11 ). Image and / or video sensor 72 may be a conventional camera, a thermal camera, or both. In some embodiments, image and / or video sensor 72 is configured similarly to image sensor 114 and, therefore, may be a CMOS image sensor.

[0091] In some embodiments, tool assembly 70 may include one or more light sources 74 mounted to distal end 22. One or more light sources 74 may be, for example, light emitting diode ("LED") light sources, lamps, or fiber optic light sources. In some embodiments, light source 74 may be configured similarly to one or more light sources 116 described above.

[0092] In some embodiments, the distal end 22 further includes openings to facilitate the passage of other secondary tools for treatment purposes within the middle ear cavity 44. Thus, the distal tool assembly 70 may include any suitable tools at the distal end 22 for performing the methods described herein. The steerable tool 20 may include a lumen through which all wiring, control lines, etc. necessary for the function of the tool assembly 70 may extend.

[0093] 18, an apparatus 100 is shown in which a tube assembly 10 is coupled to a user interface 60, according to some alternative embodiments of the present disclosure. For example, the user interface 60 may include some, all, or none of the components of the user interface 60 described above with respect to FIGS. 8A-8E, as shown.

[0094] When coupled with the user interface 60, the tube assembly 60 may provide a user-controllable device for accessing the middle ear cavity. As suggested above, the user interface 60 may be manipulated by a user to effect actuation of the steerable tool 20 described herein. As shown, the tube assembly 10 may be coupled to a hub 68 (e.g., a distal mount of the user interface 60) at the proximal end of the tube assembly. For example, the proximal end 13 of the rigid tube 12 (shown with respect to FIG. 1 ) may be coupled to the distal end 67 of the hub 68. In some embodiments, the proximal end 69 of the hub 68 includes an opening to facilitate insertion of the third flexible tube 17 into the rigid tube 12. Thus, according to some embodiments, the device 100 may be configured such that the third flexible tube 17 is fed into the rigid tube 12 from an external source (rather than being integrally telescopically present within the rigid tube 12). Similarly, the steerable tool may be fed into the third flexible tube 17. In such embodiments, the third flexible tube 17 and / or the steerable tool 20 may be manually guided by a user to perform the staged deployment described herein. In another embodiment, the rigid tube 12, the third flexible tube 17, and the steerable tool 20 are integrally configured with one another in a telescopic manner. In such embodiments, the user interface 60 includes various actuators that a user can control to extend the third flexible tube 17 and / or the steerable tool 20 to perform the staged deployment described herein.

[0095] In some embodiments, user interface 60 (with particular reference to handle 62 of user interface 60) is configured as a controller including control mechanisms (e.g., buttons, switches, etc.) for commanding (e.g., sending control signals for) functions of tube assembly 10. For example, user interface 60 may include components for stabilizing tube assembly 10, axially rotating tube assembly 10, advancing / retracting third flexible tube 17 and / or steerable tool 20, deflecting (e.g., steering) steerable tool 20, and / or operating any components mounted on steerable tool 20 (e.g., tool assembly 70 including image and / or video sensor 72 and / or one or more light sources 74) throughout a procedure to access middle-ear cavity 44 or other anatomical region. User interface 60 may be configured to send one or more control signals to one or more actuators to do so. As one example, the user interface 60 may include a linear actuator 66 that controls the advancement and / or retraction of the third flexible tube 17 relative to the rigid tube 12 (e.g., the second stage deployment described above with reference to FIG. 5 ) and the advancement and / or retraction of the steerable tool 20 relative to the third flexible tube 17 (e.g., the third stage deployment described above with reference to FIG. 6 ). As another example, the user interface 60 may include a steerable tool actuator 64 that controls the deflection of the steerable tool 20 described above with reference to FIGS. 9C-9D . As yet another example, the handle 62 itself may be rotated to rotate the entire tube assembly 10. As described above, the steerable tool 20 may be implemented to allow bidirectional bending. Rotation of the steerable tool by the user interface 60 may be required to allow full range steering control of the distal end 22 of the steerable tool 20.

[0096] In some embodiments, the steerable tool actuator 64 incorporates a mechanical stop that prevents over-actuation of the steerable tool (e.g., pushing and / or pulling the first flexible tube 28 and / or the second flexible tube 23 to the point where material damage to the steerable tool 20 may occur). In some embodiments, the steerable tool actuator 64 feature is not back-driveable or incorporates a mechanism that is engaged to prevent the steerable tool 20 from automatically returning to its neutral (straight) position (e.g., the configuration of the steerable tool 20 shown with respect to FIG. 6B ). The user interface 60 may include markings or reference features to assist the user in targeting and adjusting the position and deflection of the steerable tool 20 as the steerable tool 20 is advanced into a patient's anatomy (e.g., the nasal passage 40, the Eustachian tube 42, or the middle ear cavity 44). The user interface 60 may be battery powered or, in some embodiments, may include a cable 61 coupled to a proximal end 63 of the user interface 60 to obtain power for the above-described actuation.

[0097] In some embodiments, the handle proximal end 63 includes a port for any external wiring associated with the tool assembly 70 (e.g., any wiring not normally located within the user interface 60 during normal use). In some embodiments, the user interface 60 includes buttons for controlling the tool assembly 70. For example, the user interface 60 may include buttons for controlling the image and / or video sensor 72 and / or one or more light sources 74, including, but not limited to, buttons for controlling brightness, white balance, screen capture, and auto gain.

[0098] 19, a device 100 configured for middle ear access according to some embodiments of the present disclosure is shown, including the external control unit 180 described above. As such, the external control unit 180 can interface with various components of the user interface 60 in the context of providing middle ear access. As further illustrated, the user interface 60 described above with respect to FIGS. 8A-8E can be configured to be retrofitted with various components to implement the middle ear access methods described herein. For example, a hub 68 can be provided coupled to the rigid tube 12 (with the third flexible tube 17 disposed therein) and can be assembled to a linear actuator 66 coupled to the second flexible tube 23, and the aforementioned components can be assembled to an actuator 60 coupled to the first flexible tube 28.

[0099] While specific embodiments of the present invention have been described above as novel and useful "endoscopy methods and apparatus," such references are not intended to be construed as limiting the invention.

Claims

1. a steerable tool having a first flexible tube concentrically nested within a second flexible tube; an image sensor disposed on the steerable tool; one or more light sources disposed on the steerable tool; Including, the first flexible tube includes a first deflectable portion and the second flexible tube includes a second deflectable portion, the first and second deflectable portions being selectively weakened portions of the first and second flexible tubes that are angularly oriented in directions offset from one another by an angle of 180 degrees or less relative to a longitudinal axis of the steerable tool; the steerable tool is actuatable to cause the first flexible tube and the second flexible tube to axially translate relative to one another to form a bend; Endoscopic device.

2. The apparatus of claim 1 , wherein the image sensor comprises a digital complementary metal-oxide semiconductor (CMOS) image sensor.

3. The device of claim 1 , wherein the first and second deflectable portions each comprise a serpentine profile of material cut from the first and second flexible tubes.

4. The apparatus of claim 1 , wherein the first and second deflectable portions each include a series of cutouts spaced along the longitudinal axis of the steerable tool.

5. further comprising a user interface; a proximal end of the steerable tool secured to the user interface; The user interface is a handle, the handle comprising: a thumb-actuated lever; a mechanical transmission that converts rotational movement of the lever into linear translation between the first flexible tube and the second flexible tube, the mechanical transmission actuating the steerable tool to form a bend; and Including, 10. The apparatus of claim 1.

6. The apparatus of claim 5 , further comprising an external control unit, the external control unit comprising a power supply configured to provide power to the image sensor and the one or more light sources.

7. further comprising an end cap disposed on the steerable tool; the image sensor is disposed on the end cap; the one or more light sources are disposed on the end cap; 10. The apparatus of claim 1.

8. a steerable tool having a first flexible tube concentrically nested within a second flexible tube; a third flexible tube, the steerable tool being disposed within the third flexible tube and being axially movable relative to the third flexible tube; a rigid tube, the third flexible tube being disposed within the rigid tube and axially movable relative to the rigid tube; an image sensor disposed on a distal end of the steerable tool; one or more light sources disposed on the distal end of the steerable tool; Including, the first flexible tube includes a first deflectable portion and the second flexible tube includes a second deflectable portion, the first and second deflectable portions being selectively weakened portions of the first and second flexible tubes that are angularly oriented in directions offset from one another by an angle of 180 degrees or less relative to a longitudinal axis of the steerable tool; the steerable tool is actuatable to cause the first flexible tube and the second flexible tube to axially translate relative to one another to form a bend; Endoscopic device.

9. the rigid tube is a cannula having a preformed curvature that forms an angle between a first axis defined by a distal portion of the rigid tube and a second axis defined by a proximal portion of the rigid tube; the angle is from about 110 to about 160 degrees; the third flexible tube is a catheter; 9. The apparatus of claim 8.

10. 10. The apparatus of claim 9, wherein the image sensor is a digital complementary metal oxide semiconductor (CMOS) image sensor.

11. The device of claim 10 , wherein the first and second deflectable portions each comprise a serpentine profile of material cut from the first and second flexible tubes.

12. The apparatus of claim 10 , wherein the first and second deflectable portions each include a series of cutouts spaced along the longitudinal axis of the steerable tool.

13. further comprising a user interface; a proximal end of the steerable tool is secured to the user interface; The user interface is a handle, the handle comprising: a thumb-actuated lever; a mechanical transmission that converts rotational movement of the lever into relative linear translation between the first flexible tube and the second flexible tube, the mechanical transmission actuating the steerable tool to form a bend; and Including, 11. The apparatus of claim 10.

14. The apparatus of claim 13 , further comprising an external control unit, the external control unit comprising a power supply configured to provide power to the image sensor and the one or more light sources.

15. 1. A method of accessing an area within a patient's middle ear cavity, comprising: providing a steerable tool having a first flexible tube concentrically nested within a second flexible tube; placing at least a portion of a rigid tube within a nasal passageway, the nasal passageway communicating with the middle ear cavity with the Eustachian tube between the nasal passageway and the middle ear cavity; extending a third flexible tube from the lumen of the rigid tube, wherein at least a portion of the third flexible tube protrudes from an opening formed by a distal end of the rigid tube, and the distal end of the third flexible tube is positioned along the Eustachian tube toward the middle ear cavity; extending the steerable tool from the lumen of the third flexible tube, wherein at least a portion of the steerable tool protrudes from an opening formed by the distal end of the third flexible tube and the distal end of the steerable tool is positioned within the middle-ear cavity; actuating the steerable tool such that the steerable tool forms a bend, the distal end of the steerable tool being steered toward the region within the middle-ear cavity; A method comprising:

16. the rigid tube is a cannula having a preformed curvature that forms an angle between a first axis defined by a distal portion of the rigid tube and a second axis defined by a proximal portion of the rigid tube; the angle is from about 20 to about 70 degrees; the third flexible tube is a catheter; 16. The apparatus of claim 15.

17. positioning an image sensor on the distal end of the steerable tool; disposing one or more light sources on the distal end of the steerable tool; 17. The method of claim 16, further comprising:

18. 17. The method of claim 16, wherein the outer diameter of the steerable tool is about 1.6 millimeters or less.

19. 18. The method of claim 17, wherein the outer diameter of the third flexible tube is about 3 millimeters or less.

20. 20. The method of claim 18, wherein the at least a portion of the steerable tool is configured to protrude from about 20 to about 40 millimeters from the opening formed by the distal end of the third flexible tube during actuation of the steerable tool.

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