Tunable ball lens for endoscopy

Abstract

Provided is forward-viewing angioscope for insertion into a cerebrovasculature of a human subject. The angioscope includes a distal segment including an imaging sensor, a ball lens at least partially covering the imaging sensor, and an illuminator. The ball lens includes a fluid barrier defining an inner cavity, a flexile sheath extending longitudinally from the distal segment toward a proximal end of the angioscope, electrical cabling disposed within the flexile sheath and extending within the flexile sheath to communicatively couple the imaging sensor of the distal segment with an outlet at or near the proximal end of the angioscope, and at least one fluid channel, disposed within the flexile sheath, in fluid communication with the inner cavity of the ball lens and configured for receiving fluid at or near the proximal end of the angioscope and delivering the fluid to the inner cavity of the ball lens.

Description

TUNABLE BALL LENS FOR ENDOSCOPYCLAIM OF PRIORITY

[0001] This application is a claims priority to Canadian Provisional Patent Application Serial No. CA 3251750, which is incorporated by reference herein in its entirety and the benefit of priority of which is claimed herein.BACKGROUND

[0002] Cerebrovascular pathologies can include, among other things, a thrombus (blood clot) or an aneurysm (localized enlargement or weakening of a blood vessel). A cerebrovascular thrombus can be associated with ischemic stroke, which, in turn can cause damage to brain tissue. A cerebrovascular aneurysm can be associated with a risk of rupture and hemorrhagic stroke, which, in turn can also cause damage to brain tissue.

[0003] Certain angioscopy techniques can facilitate direct visualization of blood vessels and other anatomical structures through minimally invasive means. The cerebrovasculature presents unique challenges for imaging and navigation due to its complex network of vessels, including the petrous segment of the carotid artery and intracranial vessels. Certain imaging approaches for cerebrovascular procedures include fluoroscopy and computed tomography, which provide limited resolution for detailed tissue assessment.BRIEF DESCRIPTION OF THE DRAWINGS

[0004] In the drawings, which are not necessarily drawn to scale, like numerals can describe similar components in different views. Like numerals having different letter suffixes can represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

[0005] FIG. 1 A depicts an example of an angioscope for navigating cerebrovasculature.

[0006] FIG. IB depicts an example of an imaging processor for coupling with the angioscope of FIG. 1A.

[0007] FIG. 1C is a magnified view of a tip of the angioscope of FIG. 1A, including a ball lens.

[0008] FIG. 2 is a diagram showing a cross-sectional view of an endoscope with an adjustable, spherical ball lens

[0009] FIG. 3 depicts several cross-sectional views of various examples of multi-lumen extrusions for endoscopy.

[0010] FIG. 4 depicts examples of a semispherical ball lens for endoscopy.

[0011] FIG. 5 depicts a process for manufacturing an example of a ball lens.

[0012] FIG. 6 is a flowchart showing a process for establishing or adjusting properties of a ball lens during endoscopy.

[0013] FIG. 7 is a block diagram of a machine.DETAILED DESCRIPTION

[0014] Medical endoscopy is minimally invasive technique for facilitating the direct observation of internal structures, such as organs, tissues, and blood vessels. Medical endoscopy can reduce or replace certain other invasive surgeries, providing patients quicker recovery times, less discomfort, and lower risk of complications. Endoscopic systems can involve using an endoscopic camera including an optical lens, which can facilitate capture of vasculature.

[0015] One type of optical lens is a spherical or semispherical “ball lens”, e.g., formed of optical glass or fused silica, such as to provide transparency. The symmetrical shape of a ball lens relatively uniform curvature can help facilitate focusing or collimating light, which can be especially useful in compact imaging systems such as involving angioscopes or microangioscopes, where a need for precision and versatility must be balanced with strict space limitations. Certain approaches to ball lenses for endoscopic viewing can involve forming a ball lens in a fixed (e.g., inflexible, unchangeable) shape. Such a fixed shape can provide that the lens's focal length, field of view (FOV), and resolution all remain fixed.

[0016] Certain medical situations can involve challenging viewing circumstances during diagnosis or treatment. Chronic Total Occlusion (CTO) is one such challenging medical scenario. Here, a large field of view can facilitate navigating to the occlusion's face for pathological assessment and for selecting the right interventional tools. This wide view is maintained while attempting to cross the lesion, and after crossing, high-resolution capabilities of the microangioscope are necessary to accurately locate the newly created lumen for further assessment.

[0017] Assessing plaque vulnerability also benefits from a broad field of view, which helps in identifying the affected area and assessing the disease's impact along the vessel's arc. Once the affected area is identified, high-resolution imaging is helpful for precisely determining plaque vulnerability or locating the rupture site responsible for a thrombogenic event.

[0018] Certain angioscopes can be particularly useful during procedures such as abdominal aortic aneurysm (AAA) repair, providing a wide field of view that aids in navigating and cannulating branch vessels. This visibility helps in precise access to complex vascular branches, such as the renal arteries. After the branch vessels are cannulated, switching to a narrower field of view with higher resolution is helpful for assessing the main stent graft and its connections to the branches. High-resolution imaging helps in identifying any potential gaps or irregularities that could lead to endoleaks, thereby supporting a proper seal and longterm procedural success. However, certain other approaches (e.g., conventional “ball lenses”) present challenges in that they generally include fixed properties and do not offer significant modification of optical properties for imaging during a procedure.

[0019] The present inventors have recognized the benefits of techniques for controlling or tuning optical properties of a ball lens, such as to establish focal length, FOV, resolution, refractive index, etc. of the ball lens according to specified parameters. In an example, the optical properties of a ball lens can be established or adjusted, e.g., according to a desired view of vasculature to be imaged during a procedure. For example, the ball lens can include a cavity for receiving fluid, and fluid supplied to the cavity can be controlled such as to control the optical properties of the ball lens, such as refractive index (RI). In an example, the ball lens can include an elastic barrier or wall, configured to expand or contract according to a volume of fluid supplied to the cavity. Such construction can provide control of a physical property of the ball lens, such as to establish a specified shape (e.g., radius of the lens), and in turn, to control a focal length of the lens according to a desired view therethrough. In certain examples, such physical properties of the ball lens can by dynamically adjusted, e.g., concurrently with imaging therethrough and during a procedure, such as to tune a FOV, resolution, etc. according to a desired view of the vasculature.

[0020] FIG. 1A depicts an example of an angioscope for navigating cerebrovasculature. In an example, an angioscope 102 can include a flexile sheath 108, and a distal segment 106 including a distal tip 116 having an imaging sensor 124 and an illumination source. The flexile sheath 108 can establish at least a part of a proximal segment 104, which can extend to a transition coupling 110, which can be arranged as a bifurcated joint for breaking out imaging and power cabling to an illumination plug 112 and an imaging plug 114, respectively. The illumination plug 112 and the imaging plug 114 can each be removably coupled with an illumination receptacle 122 and an imaging receptacle 120, respectively, of an imaging processor 118 (as depicted in FIG. IB).

[0021] In an example, the angioscope 102 has a distal segment 106 with a diameter less than about 3.5 French (Fr) or less than about 0.045 inches (in) distal tip. Here, the distal segment106 can have a greater largest diameter than that of the proximal segment 104, which can have a largest diameter along its length (e.g., up to the transition coupling 110) of less than 3 Fr or less than about 0.039 in. In an example, the flexile sheath 108 can include a step down (e.g., at or near the distal segment 106 from a diameter of about 4 mm toward a diameter of about 3 Fr extending toward a proximal end. In an example, at least the proximal segment 104 and the distal segment 106 can be introduced to patient anatomy via a parent catheter or via balloon irrigation. For example, the angioscope 102 can be used with a parent catheter or other introducer system with an insertion portion width at least one millimeter (mm) wider in diameter than that of the distal segment 106, such as greater than about 2.5 Fr, greater than about 3 Fr, or greater than about 3.6 Fr.

[0022] In example, the proximal segment 104 and the distal segment 106 can have a combined length within a range of about 140 centimeters (cm) and about 180 cm. In an example, the flexile sheath 108 can be formed as a laser-cut hypotube. Alternatively or additionally, the flexile sheath 108 can formed of one or multiple waveguides (e.g., formed via strands of optical fiber), such as concurrently establishing the illumination source.

[0023] FIG. IB depicts an example of an imaging processor for coupling with the angioscope of FIG. 1A. In an example, a system for imaging c er ebro vasculature can include the angioscope 102 and an imaging processor 118. The imaging processor 118 can include circuitry for providing power, image processing, and video output to the angioscope 102, such as via cabling disposed within the flexile sheath 108. In an example, the imaging processor 118 can including a housing having a front panel user interface, the imaging plug 114 for communicatively coupling with an imaging sensor 124 at the distal tip 116, and the illumination plug 112 for providing illumination via the illumination source. The user interface of the imaging processor 118 can include user controls, such as for triggering capture of a still image or capture of recorded video, such as in addition to toggling image processing settings. In an example, to promote sterility in an angiosuite environment, the imaging processor 118 can be fully draped with a covering 126 during operation and use.

[0024] FIG. 1C is a magnified view of a tip of the angioscope of FIG. 1A. In an example, the 102 includes an imaging sensor 124 arranged at the distal tip 116 in a “chip-on-tip” configuration, such as allowing increased flexibility at the distal tip 116 compared to other fiberoptic imaging sensors including coherent fiber bundles. In an example, the imaging sensor 124 can include a Complementary Metal-Oxide-Semiconductor (CMOS) arranged to provide an imaging signal in full color, for facilitating forward viewing, imaging of a vessel into which the distal tip 116 has been inserted. In an example, the imaging sensor 124 can be at least partially covered via a ball lens 128, arranged at the distal tip of the distal segment106, the ball lens 128 to provide an image to the imaging sensor 124 and further discussed below with respect to FIG. 2 and FIG. 4. In an example, the distal segment 106 includes a relatively short (e.g., less than about 4 mm, such as having a rigid section of less than 4 mm (e.g., about 1.68 mm) at or near the distal tip 116). For example, the distal segment 106 can have a rigid section of less than about 3 mm, less than about 2mm, such as at about 1.68 mm. The distal segment 106 can include a flexible portion, adjacent and proximal to the rigid section, for promoting navigation of the distal segment 106 through certain tortuous vessels.

[0025] In an example, the imaging processor 118 can including processing circuitry (e.g., a graphics processing unit (GPU), such as including real-time frame interpolation (e.g., such as NVIDIA DLSS4 or naive frame interpolation) for receiving an imaging signal via the imaging sensor 124 and displaying an image in real time and at a high definition (e.g., greater than about 400 vertical pixels or greater than about 400 vertical pixels and at a frame rate greater than about 24 frames per second (FPS) or greater than about 30 FPS). In an example, the processing circuitry of the imaging processor can convert an imaging signal received at a frame rate of about 30 FPS and convert the graphics to a frame rate of 60 FPS, such as using a machine learning model to construct synthetic frames for disposing between actual captured frames. For example, the imaging processor 118 can have memory including instructions that, when executed by a system processor (e.g., a central processing unit (CPU) or GPU) to receive consecutive real image frames captured by the imaging sensor 124 and to predict and generate at least one synthetic frame inserted between the consecutive real image frames based on motion vectors and learned features. For example, the system processor can access a trained neural network model to analyze temporal and spatial features of the received image frames to predict motion. In an example, the processing circuitry of the imaging processor 118 can combine the synthetic frames with the real frames into a continuous video signal at a higher effective frame rate than the native frame rate of the imaging sensor 124. Such increased FPS can help facilitate better image analysis by the end user and allow for slowing down the video feed, such as to search for certain still images to aid in clinical decisions.

[0026] In another example, the image processor 118 can perform object detection to localize and classify objects of interest, such as other medical devices used in conjunction with the angioscope 102 and pathology observed. The image processor 118 can receive consecutive real image frames captured by the image sensor 124 and generate bounding boxes and masks of objects of interest, while also providing labels of the object using neural network models, in real time. Additionally, the classification of objects of interest can include pathological indicators and grading to provide users with greater information on the potential pathology observed and aid in clinical decisions. In an example, the image processor 118 can receivevideo data from the image sensor 124 and consolidate clinically relevant sections of video captured in vivo. For example, the image processor 118 can perform video frame thresholding (e.g., based on average pixel value), such as to facilitate rapid identification of frames to be removed. For example, if it is desirable for a certain procedure to remove sections of the video where it’s the user tracking the device and only blood (red) is in view, the image processor 118 can naively average all pixel values and use thresholding flag irrelevant frames for removal. Such image processing can be used to help construct clinical highlight videos, where relatively long (e.g., minutes) periods of mostly static video frames can be identified and removed by the image processor 118 such as to shorten the a resulting clinical highlight video to only the clinically-relevant parts.

[0027] In an example, the image processor 118 can access a dataset of labelled pre-clinical data, such as an input to a cerebrovascular pathology detection or tracking model. For example, the image processor 118 can perform automated feature identification, e.g., using bounding box detection and segmentation techniques using a pre-trained model with the labelled pre-clinical data as an input. For example, the pre-trained model can include deep learning object detection architectures such as Faster R-CNN, Mask R-CNN, or YOLOv9.

[0028] In an example, the image processor 118 can perform at least one of illumination correction or specular reflectance removal of images received by the imaging sensor 124. For example, illumination correction, or white balancing can be performed (e.g., in real-time during image capture) to facilitate that colors being recorded and monitored are sufficiently accurate for end user (e.g., physician) detection of clinically relevant features in the cerebrovasculature. For example, the image processor 118 can perform gray-world, white patch, and ground truth white balance correction of images captured via the imaging sensor 124.

[0029] FIG. 2 is a diagram showing a cross-sectional view of an endoscope with an adjustable, spherical ball lens. In an example, the angioscope 102 can include a flexile sheath 108, at least partially encapsulating or enclosing electrical cabling 236, at least one illuminator 234, and at least one fluid channel 240. The angioscope 102 can include an imaging sensor 124 located at or near a distal portion of the angioscope 102, and the ball lens 128 can provide the imaging sensor 124 with an image for imaging. In an example, the ball lens 128 can at least partially cover the imaging sensor 124. Additionally, a coating 238 can be provided between the imaging sensor 124 and the ball lens 128, such as to separate a surface of the imaging sensor 124 from the ball lens 128 (e.g., or fluid contained within the ball lens 128). The ball lens can include a fluid barrier or wall 224, and the barrier 224 can define an inner cavity of the ball lens 128. For example, the inner cavity defined by the barrier224 can be fluidly separated from an ambient environment outside the endoscope. The barrier 224 can be formed of a flexile or elastic material and can be substantially transparent or translucent, where a resulting radius R of the ball lens 128 (established by the barrier 224) can be established or adjusted according to fluid supplied to the inner cavity of the ball lens 128. Alternatively, the barrier 224 can be formed of a solid material and can establish a fixed radius R. For example, the barrier 224 can be formed via balloon extrusion, dip coating, filmcasting, blow molding, etc. The barrier 224 of the ball lens 128 can be substantially spherical or semispherical. In an example, the barrier 224 can be formed of a thin wall ranging from about 50 to about 150 micrometers. Alternatively, the barrier 224 can be constructed of relatively thicker walls, such as between about 150 and about 500 micrometers, such as to withstand higher inflation pressures or provide increased durability and resist deformation under stress.

[0030] The angioscope 102 can include a flexile sheath 108, at least partially containing or housing illuminator 234. The illuminator 234 can be formed of fiber for transmitting light between a light source 226 and a distal tip of the angioscope 102 Alternatively or additionally, the illuminator 234 can include one or more light emitting diodes (LEDs) and can receive signal (e.g., power, control, etc.) from the light source 228, The flexile sheath 108 can at least partially contain or house electrical cabling 236. For example, the electrical cabling 236 can extend within the flexile sheath 108 between an imaging processor 118 and the imaging sensor 124, such as to communicatively couple the imaging sensor 124 and the imaging processor 118. The flexile sheath 108 can also at least partially contain, house, or otherwise define one or more fluid channels 240. The one or more fluid channels 240 can be arranged such that they are in fluid communication with the inner cavity of the ball lens 128 and configured for receiving fluid at or near the proximal end of the angioscope and delivering the fluid to the inner cavity of the ball lens 128. For example, fluid can be received at a fluid port 242 located at or near the proximal end of the angioscope, such as supplied via a syringe, pump, or microfluidic system.

[0031] Fluid supplied to the inner cavity of the ball lens 128, via the one or more fluid channels 240, can include saline mixed with high-refractive-index nanoparticles at a biocompatible concentration to achieve a specified target refractive index. For example, such fluid can be prepared by mixing a base liquid, such as saline with high-refractive-index nanoparticles like titanium dioxide (TiCL). Other medically safe and transparent fluids, such as contrast agents, can also be used as the base liquid. For example, fluids with inherent high refractive indices, such as certain contrast agents, can reduce or negate a need for nanoparticles. For example, iodinated contrast media used in fluoscopic / interventional(Omnipaque®) procedures, such as iodixanol (Visipaque®) or iohexol can be used to create the fluid. In addition to TiCh, other nanoparticles like amorphous silicon, zirconium dioxide (ZrCh), or lead sulfide (PbS) can be added to the base liquid to adjust the refractive index of the fluid, e.g., according to certain specific imaging requirements.

[0032] Herein, “nanoparticles” refers to particles ranging from 1 to 100 nanometers in at least one dimension, and exhibiting optical properties according to their size, shape, and composition. The refractive index of nanoparticles can differ significantly based on factors such as their material composition and the medium in which they are dispersed. For example, silicon nanoparticles have a higher refractive index as compared with silica (SiCh) nanoparticles. As these particles approach the wavelength of light, their scattering and absorption characteristics change, influencing their effective refractive index. Certain smaller nanoparticles tend to reflect the refractive index of the bulk material more closely, whereas larger nanoparticles, approaching 100 nm, may see altered indices due to surface effects and quantum confinement. When nanoparticles are dispersed in a medium such as saline to form the fluid supplied to the inner cavity of the ball lens 128, the refractive index of the resulting suspension can be influenced by both the particles' properties and those of the saline. This effective refractive index is determined by the volume fraction and spatial distribution of the nanoparticles, following principles laid out in effective medium theories like the Maxwell- Garnett or Bruggeman models. Certain metallic nanoparticles like gold and silver display pronounced optical properties due to surface plasmon resonance, which can significantly alter the refractive index at specific wavelengths. Additionally, high-refractive-index dielectric nanoparticles such as titanium dioxide (TiCh) and zinc oxide (ZnO) can increase the refractive index of the solutions they are in.

[0033] In an example, the fluid supplied to the inner cavity of the ball lens 128 can be dynamically altered (e.g., concurrently with imaging through the ball lens 128 or during a medical procedure) such as by establishing or adjusting a concentration or type of nanoparticles in the fluid 226. In an example, when the inner cavity of the ball lens 128 is filled with a fluid volume, the barrier 224 can expand or contract such as to establish a radius R. Here, a type nanoparticle included in the fluid, the Radius, and the composition of the base liquid can determine a resulting focal length of the ball lens. In an example, concentration or type of nanoparticles can be altered, without significantly changing a fluid volume held in the inner cavity of the ball lens 128, (while maintaining a constant radius R) such as to modify a the focal length of the ball lens 128 without changing a physical property (e.g., the radius R) of the ball lens.

[0034] In an example, the illuminator 234 can transmit white light at or near a distal tip of the angioscope 102, such as to illuminate an area of interest in front of the ball lens 128. Once the area of interest is illuminated, the reflected light is captured by the ball lens 128. For example, the ball lens 128 can gather light according to its adjustable field of view and transmits the light (as an image) to the imaging sensor 124 and ultimately to the imaging processor 118 for analysis or visualization.

[0035] Alternatively, in an example the barrier 224 of the ball lens 128 can be formed of transparent, ultra-compliant balloon material. Here, at least the imaging sensor 124 (and optionally where the illuminator 234 is arranged as wafer-level LEDs) can be disposed on a chip (e.g., a CMOS chip) and each covered with a second lens located at the wafer level the chip. The second lens can be configured to provide an image to the imaging sensor 124 having a >127 degree field of view through fluid disposed in the cavity of the ball lens 128 (e.g., CO2 or other fluid mediums described herein). Thus, the ball lens 128 can establish a closed- fluid system, such that the ball lens 128 acts as a blood displacer, such as to limit or avoid a need for contrast or fluid irrigation during an angioscopy procedure. For example, the ball lens can be gently filled with fluid (e.g., inflated) and pressed against a target feature such as a vessel wall, stent, implant, or lesions such as a clot, plaque, a dissection or aneurysm, etc. Here, the imaging sensor can resolve or focus on the target feature during imaging, such as by the blood being displaced from the field of view. Such an approach can be particularly useful in imaging of certain peripheral, coronary, or neurovascular vessels.

[0036] In an example, the flexile sheath 108 can provide a certain range of deflectability and torquability, such as to provide an end user an ability to manipulate the ball lens 128 within certain larger vessels, e.g., great vessels of the heart, the aorta, the vena cava, and pulmonary artery / veins, to gently press the ball lens and to displace the blood against clots, valves, walls, ostiums, dissections etc. Such an ability of the flexile sheath 108 can provide an end user with an ability to observe, visualize, and diagnose such as without a need for significant fluid irrigation at or near a distal tip of an angioscope.

[0037] Examples described herein can provide that the optics provided by the imaging sensor 124, the ball lens 128, and the illuminator 234 can each exhibit a specified translation, torque, and deflectability such as to maneuver within the ball lens within tortuous vessels of the cerebrovasculature, e.g., to provide an end user an ability to maneuver the angioscope “get a better look” at an object of interest.

[0038] FIG. 3 depicts several cross-sectional views of various examples (308A-L) of multilumen extrusions for endoscopy. As shown in FIG. 2, the barrier 224 forming the ball lens128 can be atached to an end of a multi-lumen extrusion 308 (e.g., via epoxy or other adhesive). Here, the multi-lumen extrusion 308 can form the flexile sheath 108 (as depicted in FIG. 1A, FIG. IB, FIG. 1C, and FIG 2), such as to house the electrical cabling 236 and the one or more fluid channels 240. imaging fiber bundle 216 along with one or more fluid channels 218.

[0039] As shown in FIG. 3, the multi-lumen extrusion 308 can be formed according to different geometries or arrangements of lumens for housing the electrical cabling 236, the illuminator 234, or the one or more fluid channels 240, as well as steering wire(s) 342. For example, the multiple-lumen extrusion 240 A includes an electrical cabling 236, a pair of diametrically opposed fluid channels 240, and a pair of diametrically opposed illuminators 234 (e.g., illumination fiber bundles). In other examples, the certain diametrically opposed illumination fiber bundles can be replaced with steering wires 342, as illustrated in the examples of extrusions 308E-308L.

[0040] In the examples provided by extrusions 308D, 308H, and 308L, the fluid channels 240 can be arranged in one or more concentric rings. Furthermore, as shown in the example of the extrusion 308L, a ring light guide 346 can be included as a concentric ring. The ring light guide 346 can be formed as at least partially transparent or translucent, hollow plastic tube, arranged to light from the proximal end to the distal end, through its wall.

[0041] In an example, any of the multi-lumen extrusions 308A-308L can be formed by extruding materials through a die configured to generate multiple lumens, often utilizing several mandrels, resulting in an elongate tubular member with multiple lumens. Multi-lumen extrusions 308A-308L can be formed of a wide variety of materials, including polymers and metals. Examples of polymers that can be used include Pebax®, polyurethane, PTFE, nylon, and polyimide. Examples of metals include nitinol and stainless steel.

[0042] FIG. 4 depicts examples of a semispherical ball lens for endoscopy. While the ball lens 128 is generally depicted in FIG. 2 as having a spherical shape, ball lenses 128 described herein can include other semispherical shapes as illustrated in examples 128B, 128C and 128D. Specifically with respect to the example of the ball lens 128D, the ball lens 128 can be optionally be encapsulated with a protective layer 444. Such encapsulation can be particularly advantageous in situations where the inflatable ball lens 20 directly interacts with the object of interest, providing a robust defense against bursting from increased external pressure. Such a 444 can also provide advantages when operating within narrow channels, such as to protect against damage to surrounding tissues and limit overexpansion of a barrier of the ball lens 128 (e.g., via filling a fluid cavity of the ball lens 128 beyond capacity). In anexample, the protective layer 444 can be formed of epoxy directly at the ball lens 128. Here, the epoxy can be subsequently ground and polished to a desired thickness.

[0043] Alternatively, the ball lens can be shaped other than spherical, such as tailored for certain anatomical or surgical situations. For example, a barrier of the ball lens can be formed of a balloon which can be strained or scaffolded on one side, such as to induce balloon inflation toward a target direction. In an example, the balloon can be formed of a non- compliant material, such as to provide real-time imaging and guidance during an embolectomy, atherectomy, chronic total occlusion, mechanical thrombectomy, angioplasty, balloon-mounted stent deployment, valvoplasty, valve replacement, or endoscopic third ventriculostomy in the brain ventricles.

[0044] FIG. 5 depicts a process for manufacturing an example of a ball lens. Alternatively or additionally to certain expandable or fluidly -filled examples of ball lenses described herein, an example of a ball lens can be formed on an imaging sensor (e.g., a CMOS sensor) directly via a laser-shaped silica material. Such an example of a silica ball lens can formed to have optical properties similar to those with respect to fluid-filled ball lenses (e.g., ball lens 128 with respect to FIG. 2) described elsewhere herein.

[0045] At 502, an imaging sensor 124 can be received. The imaging sensor 124 can including or be communicatively coupled with (e.g., via a soldering or other electrical joint) an electrical cabling 236 extending from the imaging sensor along a longitudinal axis.

[0046] At 504, a silica material 508 can be secured to the imaging sensor 124 via an adhesive material and infrared (IR) light can be applied via a gas laser to the silica material 508 to heat the silica material 508. The silica material 508 can be a silica rod or disc, and the adhesive can be epoxy or other suitable adhesive for securing the silica material 508 to a CMOS sensor. The gas laser can be a CO2 laser (e.g., a LZM-125 CO2 Laser), configured for shaping and fuse the silica material 508, such as to create of small optical lenses. Such a ball lens formed by the gas laser can be relatively small, e.g., having a diameter ranging from a few hundred microns to a few millimeters, user-controllable during the manufacturing process according to a specified use scenario. In an example, during the application of the IR light via the gas laser, the imaging sensor 124, the silica material 508, or both can be rotated such as to cause the silica material 508 to melt in a spherical shape. In an example, such rotation can be performed at a rate within a range of about 50 rotations per minute (RPM) and about 500 RPM, such as within a range of about 150 RPM and about 400 RPM or within a range of about 200 RPM and about 300 RPM. Surface tension naturally pulls the melted silica material508 into a round, smooth ball lens, which minimizes aberrations and enhances light-coupling efficiency.

[0047] At least one parameter of the gas laser can be established or adjusted to control a resulting curvature of the silica material 508 disposed over the imaging sensor 124. For example, during the applying the infrared light to the silica material, a temperature at the silica material can be monitored such as to control the establishing or adjusting the at least one parameter of the gas laser according to specified target curvature parameters of the resulting silica material disposed over the ball lens. The at least one parameter of the gas laser can include, e.g., at least one of a wavelength, amplitude, flow speed, irradiance, or gas content of the gas laser. In an example, such a temperature can be controlled within a range of 1500 °C and 2000 °C such as to avoid ablation of the silica material.

[0048] At 506, the resulting ball lens is established. Here, the ball lens has a defined focal length, depending on its diameter and refractive index, which can be ideal for certain medical applications where light needs to be focused efficiently. Once formed, the scope tip cools, solidifying into a clear, spherical ball lens. The lens is inspected under a microscope for shape consistency and surface quality, as these factors impact light focusing and coupling. Optical tests, such as measuring the focal point and spot size, may also be performed to ensure it meets performance criteria.

[0049] FIG. 6 is a flowchart showing a process 600 for establishing or adjusting properties of a ball lens during endoscopy.

[0050] At 602, an image of cerebrovasculature can be received from an imaging sensor of an angioscope. The angioscope can include a distal segment including an imaging sensor, a ball lens at least partially covering the imaging sensor, and an illuminator, wherein the ball lens includes a fluid barrier defining an inner cavity. The angioscope can also include a flexile sheath extending longitudinally from the distal segment toward a proximal end of the angioscope, and electrical cabling disposed within the flexile sheath and extending within the flexile sheath to communicatively couple the imaging sensor of the distal segment with an outlet at or near the proximal end of the angioscope.

[0051] At 604, fluid can be provided, via at least one fluid channel disposed within the flexile sheath, to the inner cavity of the ball lens to establish or adjust at least one optical property of the ball lens. For example, an amount and type of fluid provided can established or adjusted based on the image received from the imaging sensor, e.g., concurrently with the receiving the image through the ball lens and via the imaging sensor. For example, the inner cavity of the ball lens can be expandable, and the barrier of the ball lens is can be formed ofan elastic material configured to expand or contract based on a fluid volume received by the inner cavity of the ball lens. Various optical properties of the ball lens can be adjusted based on the fluid provided, such as a focal length of the lens, a field of view (FOV) of the lens, a refractive index of the lens, or a resolution or distortion of the image provided by the lens to the imaging sensor.

[0052] FIG. 7 illustrates generally an example of a block diagram of a machine 701 upon which any one or more of the techniques (e.g., methodologies) discussed herein may perform in accordance with some examples. In alternative embodiments, the machine 701 may operate as a standalone device or may be connected (e.g., networked) to other machines. In a networked deployment, the machine 701 may operate in the capacity of a server machine, a client machine, or both in server-client network environments. In an example, the machine 701 may act as a peer machine in peer-to-peer (P2P) (or other distributed) network environment. The machine 701 may be a personal computer (PC), a tablet PC, a set-top box (STB), a personal digital assistant (PDA), a mobile telephone, a web appliance, a network router, switch or bridge, or any machine capable of executing instructions (sequential or otherwise) that specify actions to be taken by that machine. Further, while only a single machine is illustrated, the term “machine” shall also be taken to include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein, such as cloud computing, software as a service (SaaS), other computer cluster configurations.

[0053] Examples, as described herein, may include, or may operate on, logic or a number of components, modules, or mechanisms. Modules are tangible entities (e.g., hardware) capable of performing specified operations when operating. A module includes hardware. In an example, the hardware may be specifically configured to carry out a specific operation (e.g., hardwired). In an example, the hardware may include configurable execution units (e.g., transistors, circuits, etc.) and a computer readable medium containing instructions, where the instructions configure the execution units to carry out a specific operation when in operation. The configuring may occur under the direction of the executions units or a loading mechanism. Accordingly, the execution units are communicatively coupled to the computer readable medium when the device is operating. In this example, the execution units may be a member of more than one module. For example, under operation, the execution units may be configured by a first set of instructions to implement a first module at one point in time and reconfigured by a second set of instructions to implement a second module.

[0054] Machine (e.g., computer system) 701 may include a hardware processor 702 (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core,or any combination thereof), a main memory 703 and a static memory 704, some or all of which may communicate with each other via an interlink (e.g., bus) 705. The machine 701 may further include a display unit 706, an alphanumeric input device 707 (e.g., a keyboard), and a user interface (UI) navigation device 708 (e.g., a mouse). In an example, the display unit 706, alphanumeric input device 707 and UI navigation device 708 may be a touch screen display. The machine 701 may additionally include a storage device (e.g., drive unit) 709, a signal generation device 710 (e.g., a speaker), a network interface device 711, and one or more sensors 712, such as a global positioning system (GPS) sensor, compass, accelerometer, or other sensor. The machine 701 may include an output controller 716, such as a serial (e.g., universal serial bus (USB), parallel, or other wired or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection to communicate or control one or more peripheral devices (e.g., a printer, card reader, etc.).

[0055] The storage device 709 may include a machine readable medium 713 that is non- transitory on which is stored one or more sets of data structures or instructions 714 (e.g., software) embodying or utilized by any one or more of the techniques or functions described herein. The instructions 714 may also reside, completely or at least partially, within the main memory 703, within static memory 704, or within the hardware processor 702 during execution thereof by the machine 701. In an example, one or any combination of the hardware processor 702, the main memory 703, the static memory 704, or the storage device 709 may constitute machine readable media.

[0056] While the machine readable medium 713 is illustrated as a single medium, the term “machine readable medium” may include a single medium or multiple media (e.g., a centralized or distributed database, or associated caches and servers) configured to store the one or more instructions 714.

[0057] The term “machine readable medium” may include any medium that is capable of storing, encoding, or carrying instructions for execution by the machine 701 and that cause the machine 701 to perform any one or more of the techniques of the present disclosure, or that is capable of storing, encoding or carrying data structures used by or associated with such instructions. Non-limiting machine-readable medium examples may include solid-state memories, and optical and magnetic media. Specific examples of machine-readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read- Only Memory (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks.

[0058] The instructions 714 may further be transmitted or received over a communications network 715 using a transmission medium via the network interface device 711 utilizing any one of a number of transfer protocols (e.g., frame relay, internet protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), hypertext transfer protocol (HTTP), etc.). Example communication networks may include a local area network (LAN), a wide area network (WAN), a packet data network (e.g., the Internet), mobile telephone networks (e.g., cellular networks), Plain Old Telephone (POTS) networks, and wireless data networks (e.g., Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards known as Wi-Fi®, IEEE 802.16 family of standards known as WiMax®), IEEE 802.15.4 family of standards, peer-to-peer (P2P) networks, among others. In an example, the network interface device 711 may include one or more physical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or more antennas to connect to the communications network 715. In an example, the network interface device 711 may include a plurality of antennas to wirelessly communicate using at least one of single-input multiple-output (SIMO), multiple-input multiple-output (MIMO), or multiple-input single-output (MISO) techniques. The term “transmission medium” shall be taken to include any intangible medium that is capable of storing, encoding or carrying instructions for execution by the machine 701, and includes digital or analog communications signals or other intangible medium to facilitate communication of such software.

[0059] The above Detailed Description can include references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention can be practiced. These embodiments are also referred to herein as “examples.” Such examples can include elements in addition to those shown or described. However, the present inventors also contemplate examples in which only those elements shown or described are provided. Moreover, the present inventors also contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein.

[0060] In the event of inconsistent usages between this document and any documents so incorporated by reference, the usage in this document controls. In this document, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, composition, formulation, orprocess that can include elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim.

[0061] In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” In this document, the term “or” is used to refer to a nonexclusive or, such that “A or B” can include “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated. In this document, the terms “including” and “in which” are used as the plain- English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, composition, formulation, or process that can include elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

[0062] The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) can be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to comply with 37 C.F.R. §1.72(b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features can be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter can lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

CLAIMSWhat is claimed is:

1. A forward-viewing angioscope for insertion into a cerebrovasculature of a human subject, the angioscope comprising: a distal segment including an imaging sensor, a ball lens at least partially covering the imaging sensor, and an illuminator, wherein the ball lens includes a fluid barrier defining an inner cavity; a flexile sheath extending longitudinally from the distal segment toward a proximal end of the angioscope; electrical cabling disposed within the flexile sheath and extending within the flexile sheath to communicatively couple the imaging sensor of the distal segment with an outlet at or near the proximal end of the angioscope; and at least one fluid channel, disposed within the flexile sheath, in fluid communication with the inner cavity of the ball lens and configured for receiving fluid at or near the proximal end of the angioscope and delivering the fluid to the inner cavity of the ball lens.

2. The angioscope of claim 1, wherein an optical property of the ball lens is end user adjustable, concurrent with imaging vasculature via the imaging sensor and through the ball lens, via the fluid received by the at least one fluid channel and delivered to the expandable inner cavity.

3. The angioscope of claim 2, wherein the inner cavity of the ball lens is expandable, and the barrier of the ball lens is formed of an elastic material configured to expand or contract based on a fluid volume received by the inner cavity of the ball lens.

4. The angioscope of claim 3, wherein the barrier of the ball lens is at least substantially spherical or semispherical, and a radius of the barrier is end user adjustable based on the fluid volume received by the inner cavity of the ball lens.

5. The angioscope of claim 4, wherein the optical property of the ball lens is a focal length of the lens.

6. The angioscope of claim 3, wherein the optical property of the ball lens is a field of view (FOV) of the lens.

7. The angioscope of claim 2, wherein the optical property of the ball lens is a refractive index of the lens.

8. The angioscope of claim 2, wherein the optical property of the ball lens is at least one of resolution or distortion of the image provided by the lens to the imaging sensor.

9. The angioscope of claim 1, wherein the at least one fluid channel includes a plurality of fluid channels, each in fluid communication with the inner cavity of the ball lens.

10. The angioscope of claim 1, wherein the at least one fluid channel is a concentric channel extending along a length of the flexile sheath.

11. A method for establishing or adjusting parameters of a ball lens during endoscopy, the method comprising: receiving an image of cerebrovasculature from an imaging sensor of an angioscope, the angioscope including: a distal segment including an imaging sensor, a ball lens at least partially covering the imaging sensor, and an illuminator, wherein the ball lens includes a fluid barrier defining an inner cavity; a flexile sheath extending longitudinally from the distal segment toward a proximal end of the angioscope; and electrical cabling disposed within the flexile sheath and extending within the flexile sheath to communicatively couple the imaging sensor of the distal segment with an outlet at or near the proximal end of the angioscope; and providing fluid, via at least one fluid channel disposed within the flexile sheath, to the inner cavity of the ball lens to establish or adjust at least one optical property of the ball lens.

12. The method of claim 11, comprising at least one of expanding or contracting the inner cavity of the ball lens based on a fluid volume received by the inner cavity of the ball lens.

13. The method of claim 12, comprising adjusting a radius of the barrier based on the fluid volume received by the inner cavity of the ball lens.

14. The method of claim 13, wherein the optical property of the ball lens is a focal length of the lens.

15. The method of claim 12, wherein the optical property of the ball lens is a field of view (FOV) of the lens.

16. The method of claim 11, wherein the optical property of the ball lens is a refractive index of the lens.

17. The method of claim 11, wherein the optical property of the ball lens is at least one of resolution or distortion of the image provided by the lens to the imaging sensor.

18. A method of manufacturing a ball lens of an endoscope, the method comprising: receiving an imaging sensor, including an electrical interconnect extending from the imaging sensor along a longitudinal axis; securing a silica material to the imaging sensor via an adhesive material; and applying, via a gas laser, infrared light to the silica material to heat the silica material; and establishing or adjusting at least one parameter of the gas laser to control a resulting curvature of the silica material disposed over the imaging sensor.

19. The method of claim 18, comprising, during the applying the infrared light to the silica material, monitoring a temperature at the silica material to control the establishing or adjusting the at least one parameter of the gas laser according to specified target curvature parameters of the resulting silica material disposed over the ball lens.

20. The method of claim 19, wherein the controlling the establishing or adjusting of the at least one parameter of the gas laser includes controlling the monitored temperature within a range of 1500 °C and 2000 °C to avoid ablation of the silica material.

21. The method of claim 18, wherein the at least one parameter of the gas laser includes at least one of a wavelength, amplitude, flow speed, irradiance, or gas content of the gas laser.

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