Medical devices with tactile sensing capabilities

Abstract

Medical devices and methods of using the same are disclosed. The exemplary medical device includes a catheter having a proximal region and a distal tip, and an array of sealed chambers arranged along the distal tip, wherein each chamber includes a distal membrane arranged along an outer surface of the distal tip and a proximal membrane extending radially inward from the outer surface. Furthermore, each proximal membrane is configured to move between a first position and an expanded position in response to changes in pressure within the chamber.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of and priority to U.S. Provisional Patent Application Serial No. 62 / 959,658, filed on January 10, 2020, the disclosure of which is incorporated herein by reference. Technical Field

[0003] The present disclosure relates to medical devices and methods for making medical devices. More particularly, the present disclosure relates to medical devices having tactile sensing capabilities. Background Art

[0004] Intracorporeal medical devices have been developed for a variety of medical applications, such as intravascular use. Some of these devices include guidewires, catheters, and the like. These devices are manufactured using any of a variety of different manufacturing methods and can be used according to any of a variety of methods. Each of the known medical devices and methods has certain advantages and disadvantages. There is a continuing need to provide alternative medical devices and alternative methods of manufacturing and using medical devices. Summary of the Invention

[0005] The present disclosure provides alternative designs, materials, manufacturing methods, and uses for medical devices. The exemplary medical device includes a catheter having a proximal region and a distal tip, and an array of sealed chambers arranged along the distal tip, wherein each chamber includes a distal membrane arranged along an outer surface of the distal tip and a proximal membrane extending radially inward from the outer surface. Furthermore, each proximal membrane is configured to move between a first position and an expanded position in response to changes in pressure within the chamber.

[0006] Alternatively or in addition to any of the above embodiments, a plurality of fibers are further included, wherein each fiber has a proximal end and a distal end, wherein the distal end of each fiber is coupled to a pressure sensor aligned with a single proximal membrane, and wherein each pressure sensor is coupled to its corresponding proximal membrane.

[0007] Alternatively or additionally to any of the embodiments above, each sensor is configured to measure an extent of movement of the proximal membrane between the first position and the expanded position.

[0008] Alternatively or additionally to any of the embodiments above, each of the array of sealed chambers is filled with an incompressible fluid.

[0009] Alternatively or additionally to any of the embodiments above, each of the array of sealed chambers is filled with an emulsion.

[0010] Alternatively or additionally to any of the embodiments above, wherein the emulsion comprises a plurality of light reflective particles disposed within an incompressible fluid.

[0011] Alternatively or additionally to any of the embodiments above, wherein the extent to which each proximal membrane expands directly corresponds to the extent of the pressure change within the corresponding chamber to which the membrane is connected.

[0012] Alternatively or additionally to any of the embodiments above, wherein each proximal membrane moves from the first position to the expanded position in response to deflection of its corresponding distal membrane.

[0013] Alternatively or additionally to any of the above embodiments, each pressure sensor is configured to transmit a pressure signal along its corresponding fiber, and wherein the pressure signal corresponds to a pressure change in the chamber to which the sensor corresponds.

[0014] Alternatively or additionally to any of the embodiments above, wherein each sealed chamber comprises a first lumen in fluid communication with a second lumen, wherein the first lumen has a first diameter, and wherein the second lumen has a second diameter different from the first diameter.

[0015] Alternatively or additionally to any of the embodiments above, each fiber in the plurality of fibers comprises an optical fiber.

[0016] Alternatively or additionally to any of the above embodiments, a distal end of each of the plurality of optical fibers is spaced apart from the proximal membrane, and wherein each of the plurality of optical fibers is configured to transmit the first optical signal to the proximal membrane.

[0017] Alternatively or additionally to any of the above embodiments, each of the first optical signals transmitted to its corresponding proximal membrane is reflected back to each corresponding optical fiber, and wherein the reflected optical signal corresponds to the deflection of each corresponding proximal membrane.

[0018] Alternatively or additionally to any of the embodiments above, wherein comparing the first light signal to the reflected light signal directly corresponds to a change in chamber pressure.

[0019] Another exemplary medical device system includes: a processor; a catheter having a proximal region and a distal tip, the proximal region coupled to the processor; and a plurality of fluid-tight chambers disposed along the distal tip, wherein each chamber includes a distal membrane disposed along an outer surface of the distal tip and a proximal membrane extending radially inward from the outer surface. The medical device also includes a plurality of fibers, wherein each fiber has a proximal end and a distal end, wherein each distal end is aligned with a discrete proximal membrane, and wherein each proximal membrane is configured to move between a first position and an expanded position in response to a change in pressure within the chamber.

[0020] Alternatively or additionally to any of the above embodiments, a plurality of pressure sensors are included, wherein each pressure sensor couples a single fiber to a single proximal membrane.

[0021] Alternatively or additionally to any of the above embodiments, each sensor is configured to measure an extent of movement of the proximal membrane between the first position and the expanded position, and wherein the sensor converts the extent of movement of each proximal membrane between the first position and the expanded position into a pressure signal.

[0022] Alternatively or additionally to any of the above embodiments, each sensor is configured to transmit a pressure signal to a processor.

[0023] Alternatively or additionally to any of the above embodiments, the processor is configured to output an array of pressure signals corresponding to pressure changes in each chamber.

[0024] An example method for measuring pressure within a body cavity includes advancing a pressure catheter to a tissue site within the body cavity, wherein the pressure catheter includes a catheter having a proximal region and a distal tip, an array of sealed chambers disposed along the distal tip, wherein each chamber includes a distal membrane disposed along an outer surface of the distal tip and a proximal membrane extending radially inward from the outer surface. The pressure catheter also includes a plurality of fibers, wherein each fiber has a proximal end and a distal end, wherein each distal end is aligned with a discrete proximal membrane. The method also includes engaging one or more distal membranes with the tissue site, deflecting one or more proximal membranes in response to engagement of the distal membranes with the tissue site, and measuring the deflection of the one or more proximal membranes, wherein the deflection of each of the one or more proximal membranes corresponds to a change in pressure within its respective chamber.

[0025] The above summary of some embodiments is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The following figures and detailed description more particularly exemplify these embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] A more complete understanding of the present disclosure may be obtained from the following detailed description considered in conjunction with the accompanying drawings, in which:

[0027] Figure 1 is a side view of an example medical device;

[0028] Figure 2 yes Figure 1 A side view of a portion of an example medical device is shown;

[0029] Figure 3 is a partial cross-sectional view of an example medical device;

[0030] Figure 4 is another partial cross-sectional view of an example medical device;

[0031] Figure 5 is another partial cross-sectional view of an example medical device;

[0032] Figure 6 is another partial cross-sectional view of an example medical device;

[0033] Figure 7 is another partial cross-sectional view of an example medical device;

[0034] Figure 8 is another partial cross-sectional view of an example medical device;

[0035] Figure 9 is another partial cross-sectional view of an example medical device;

[0036] Figure 10 is a side view of another example medical device.

[0037] While the present disclosure is susceptible to various modifications and alternative forms, details thereof have been shown by way of example in the drawings and will be described in detail. However, it should be understood that it is not intended to limit the present disclosure to the particular embodiments described. On the contrary, it is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure. DETAILED DESCRIPTION

[0038] For the following defined terms, these definitions shall apply unless a different definition is given in the claims or elsewhere in this specification.

[0039] It is assumed herein that all numerical values ​​are modified by the term "about", whether or not explicitly stated. The term "about" generally refers to a range of numbers that one skilled in the art would consider equivalent to the recited value (e.g., having the same function or result). In many cases, the term "about" can include numbers that are rounded to the nearest significant figure.

[0040] The recitation of numerical ranges by endpoints includes all numbers within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0041] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and / or" unless the content clearly dictates otherwise.

[0042] Note that when the specification refers to "one embodiment," "some embodiments," "other embodiments," etc., it indicates that the described embodiments may include one or more specific features, structures, and / or characteristics. However, such a description does not necessarily mean that all embodiments include the specific features, structures, and / or characteristics. In addition, when specific features, structures, and / or characteristics are described in conjunction with one embodiment, it should be understood that these features, structures, and / or characteristics can also be used in conjunction with other embodiments, whether or not explicitly described, unless clearly stated to the contrary.

[0043] The following detailed description should be read with reference to the accompanying drawings, in which similar elements in different drawings are numbered the same. The accompanying drawings, which are not necessarily drawn to scale, depict illustrative embodiments and are not intended to limit the scope of the invention.

[0044] Many medical procedures, including minimally invasive surgeries, endovascular procedures, procedures along the digestive and / or biliary tracts, ureteral procedures, and the like, utilize medical devices such as catheters and guidewires. In some cases, these procedures may require the clinician to utilize medical devices that, instead, include more fine and controlled motions. The use of these medical devices may improve patient outcomes and reduce trauma and / or injury to the patient. For example, designing a medical device to include fine and controlled motions may allow for easier insertion into the bile duct during endoscopic retrograde cholangiopancreatography (ERCP). Additionally, utilizing a medical device with fine, controllable motions may allow for more accurate and controlled deployment of mitral valve and / or other cardiac repair devices, for example.

[0045] It is understood that longer catheters are increasingly used to perform minimally invasive procedures, whereby the point of entry into the body is located relatively far from the surgical site. It is understood that longer length catheters may significantly limit the control and / or accuracy of the procedure to be performed. In addition, in some procedures, real-time visualization may be relatively poor, and other diagnostic techniques (e.g., ultrasound imaging, visual imaging, fluoroscopy, etc.) may provide reasonable but limited feedback to the clinician. Therefore, there is a need to design a medical device that can provide real-time, accurate feedback about the position, force sensing, etc. of the distal end of the medical device when the clinician uses the medical device in a medical procedure. It may be necessary to design a medical device to include a tactile feedback mechanism. For example, it may be necessary to design a medical device to include a microfluidic array to sense the force at the distal end of various medical devices. Therefore, an example medical device that utilizes a microfluidic array to combine a tactile feedback response is disclosed.

[0046] Figure 1 is a side view of an example medical device 10. Medical device 10 may include a catheter 12. Catheter 12 may include a distal region 14 and a proximal region 16. Catheter 12 may be designed to be relatively thin so that it can be manufactured with a relatively small outer diameter and suitable for less invasive medical procedures. For example, catheter 12 (and / or all catheter examples disclosed herein) may have an outer diameter of approximately 0.25 mm to approximately 20 mm, 0.5 mm to approximately 18 mm, 1.0 mm to approximately 15 mm, 2.5 mm to approximately 12 mm, or 5.0 mm to approximately 10 mm.

[0047] Figure 1It is further shown that the proximal region 16 of the catheter 12 can be coupled to a controller 18 (e.g., a processor). As discussed in more detail below, the controller 18 can include one or more sensors, processors, and / or signal generating elements that can communicate with the distal region 14 of the catheter 12. Furthermore, it will be appreciated that while a portion of the catheter 12 is located within the patient's body, the controller 18 can be located externally to the patient.

[0048] As described above, when catheter 12 is inserted into a closed body cavity, catheter 12 can be used to measure force and / or pressure at one or more intermediate locations along catheter 12. For example, catheter 12 can be used to measure force when performing cannulation and sensing (determining) the location of the bile duct and pancreatic duct. In addition, catheter 12 can be used to locate the correct target location in the left ventricle of the heart, the mitral valve leaflets and / or the mitral valve annulus and / or locate the target septal intersection location in the atrial septum. In addition, catheter 12 can be used to diagnose abnormal tissue or tumor location. These are just examples. It is contemplated that catheter 12 can be used to perform a variety of medical procedures.

[0049] In addition, although Figure 1 While described as including a catheter 12 coupled to a controller 18, it should be understood that the medical device 10 may include a guidewire or other similar device coupled to the controller 18. For example, the medical device 10 may include an electrophysiology catheter. However, this is not intended to be limiting. Rather, it is contemplated that the medical device 10 may include a balloon catheter, a stent deployment catheter, a sphincterotomy device, an intubation catheter, an ablation catheter, a TAVI device, and the like.

[0050] Figure 2 Show Figure 1 A detailed view of the distal region 14 is shown in FIG. Figure 2 In particular, Figure 2 The distal end (e.g., distal tip) of the catheter 12 is shown. It should be understood that the distal tip of the distal region 14 can be rounded. Additionally, as described above, it should be understood that the distal region 14 of the catheter 12 can include one or more elements and / or features designed to sense and / or measure pressure and / or forces experienced by the distal tip when engaging one or more target sites within the body. For example, Figure 2 The distal region 14 of the catheter 12 is shown to include a plurality of microfluidic units 20 arranged around the distal end of the catheter 12. As will be discussed in more detail below, each microfluidic unit 20 can be deformed in response to engagement with an in vivo tissue structure. Furthermore, the deformation of each microfluidic unit 20 can be converted into a pressure signal that can be sensed and processed by the controller 18.

[0051] Figure 2The shape of the outer surface of each microfluidic unit 20 is shown to be substantially circular. However, this is not intended to be limiting. Instead, it is contemplated that the shape of the outer surface of the microfluidic unit may be square, triangular, rectangular, oval, polygonal, combinations thereof, or any other suitable geometric shape.

[0052] Figure 3 A partial cross section of the medical device 10 is shown. In particular, Figure 3 A partial cross section of the distal region 14 of the catheter 12 is shown. For example, Figure 3 A plurality of microfluidic units 20 are shown arranged along the distal end of the distal region 14 of the catheter 12. Figure 3 It will be appreciated that each microfluidic unit 20 can extend radially inwardly toward the central longitudinal axis of the conduit 12. In some cases, the microfluidic units 20 can be collectively referred to as a microfluidic array of units.

[0053] As a general description, Figure 3 Each microfluidic unit 20 is shown to include a distal membrane 24 extending along the outer surface of the distal end of the catheter 12. Figure 3 Each microfluidic unit 20 is shown to include a fluid chamber 22. In addition, the proximal end of each fluid chamber 22 can be connected to a fiber 26. The fiber 26 can include a sensor (at Figure 3 Not shown, but in Figure 4 Each fiber 26 can extend through the lumen of the catheter 12, terminating at the controller 18. As will be described in more detail below, changes in force occurring along the distal membrane 24 can be transmitted across the sensor through the microfluidic unit 20 and ultimately along the fiber to the controller 18.

[0054] Figure 4 A close-up view of a single microfluidic unit 20 is shown. Figure 4 The microfluidic unit 20 is shown to include a distal membrane 24 that extends along the outer surface 30 of the distal region 14 of the catheter 12. It should be understood that in some examples, the distal membrane 24 of the microfluidic unit 20 can be substantially flush with the outer surface 30 of the distal region 14 of the catheter. However, in other examples, it should be understood that the distal membrane 24 can extend radially outward from the outer surface 30 of the distal region 14 of the catheter.

[0055] Figure 4It is further shown that each microfluidic unit 20 can include a fluid chamber 34 extending radially inward from the outer surface 30 of the distal region 14 of the catheter. In some examples, the fluid chamber 34 can have a depth "X" of about 0.050 mm to 1.5 mm, or about 0.075 mm to about 1.0 mm, or about 0.100 mm to about 0.750 mm, or about 0.250 mm to about 0.500 mm. In addition, in some examples, the fluid chamber 34 can have a width "Y" of about 0.090 mm to about 0.210 mm, or about 0.120 mm to about 0.180 mm, or about 0.140 mm to about 0.160 mm.

[0056] As discussed above, the fluid chamber 34 can transition into the fluid lumen 22. The fluid lumen 22 can continue to extend radially inwardly within the outer surface 30 of the distal region 14 of the catheter 12. In other words, the fluid chamber 34 and the fluid lumen 22 can be substantially aligned, with both extending radially inwardly from the outer surface 30 of the distal region of the catheter 12. In some examples, the depth "W" of the fluid lumen 22 can be: approximately 0.070 mm to 0.130 mm, or approximately 0.080 mm to 0.120 mm, or approximately 0.090 mm to 0.110 mm, or approximately 0.100 mm. Furthermore, in some examples, it is contemplated that the depth "W" of the fluid lumen 22 can be much longer than the aforementioned size ranges. For example, it is contemplated that the fluid lumen 22 can extend along any length of the catheter, including extending the entire length of the catheter.

[0057] in addition, Figure 4 Each of the fluid chamber 34 and the fluid cavity 22 shown may be filled with a fluid (e.g., an incompressible fluid) and / or a gas. Figure 4 In the example shown in FIG, the incompressible fluid in the fluid chamber 34 and the fluid cavity 22 is Figure 4 However, in some examples, it should be understood that Figure 4 The dot pattern shown in may include a gas.

[0058] Figure 4 The detailed view of further illustrates that the proximal end of the fluid chamber 34 may include a proximal membrane 35 coupled to the sensor 32. The sensor 32 may be a pressure sensor 32 designed to sense changes in pressure of the fluid chamber 34 and the fluid cavity 22 contained therein.

[0059] Figure 4It is further shown that a pressure sensor 32 can be coupled to the fiber 26. In some cases, the pressure sensor 32 can be positioned between the distal end of the fiber 26 and the proximal membrane 35 of the fluid chamber 22. Therefore, it should be understood that because the sensor 32 can be directly coupled to the proximal membrane 35, it can be configured to sense changes in the proximal membrane 35. Furthermore, the sensor 32 can not only sense changes in the proximal membrane 35, but it can also be designed to convert changes in the proximal membrane 35 into a signal that can be transmitted to the controller 18 via the fiber 26.

[0060] Figure 4 and Figure 5 Together, an example is shown in which the medical device 10 measures the pressure and / or force applied to the distal membrane 24 of the medical device 10 when the device contacts an example tissue site in the body. For example, Figure 4 The distal membrane 24 (positioned along the outer surface 30 of the medical device 10 as described above) is shown adjacent an exemplary tissue site 50 within a patient. Figure 4 It will be appreciated from the detailed view of FIG. 3 that the proximal membrane 35 of the fluid chamber has not deformed because the distal membrane 24 has not yet contacted the tissue site 50 .

[0061] Figure 5 The position of the medical device 10 is shown after the medical device 10 has been advanced so that the distal membrane 24 contacts the tissue site 50. Figure 4 and Figure 5 It will be appreciated that when the distal membrane 24 contacts the tissue site 50, the distal membrane 24 may deform (e.g., the distal membrane 24 may deform as it engages the contours of the tissue site 50). Furthermore, because the microfluidic unit 20 and the fluid chamber 22 are filled with an incompressible fluid, changes in the shape of the distal membrane 24 may cause the proximal membrane 35 to change shape. For example, Figure 5 The detailed view of FIG. 3 shows that the proximal membrane 35 changes shape (eg, expands outward, bulges proximally) in response to changes in the distal membrane 24, Figure 4 compared to.

[0062] Furthermore, as described above, the shape change of the proximal membrane 35 can be sensed by the pressure sensor 32, which can be positioned along the proximal membrane 35. Furthermore, it should be understood that the sensor 32 is capable of sensing varying degrees of deformation of the proximal membrane 35. In other words, as the clinician advances the medical device 10 distally, thereby applying increasing forces to the distal membrane 24, the proximal membrane 35 can deflect increasingly in response to the deflection of the distal membrane 24. The sensor 32 can sense (e.g., measure) these increasing forces. Furthermore, the sensor 32 can convert the physical changes in the proximal membrane 35 into force signals that can be transmitted to the controller 18 via the fibers 26.

[0063] In some examples, the proximal membrane 35 (and other proximal membranes described herein) can be a thin elastic membrane. For example, the proximal membrane can be made of silicone or structure.

[0064] Although Figure 4 and Figure 5 While an example is shown in which the sensed force is transmitted along the fibers 26 to the controller 18, it is further contemplated that, in another example, the fluid lumen 22 may extend the entire length of the catheter 12, whereby the proximal membrane 35 may be positioned outside the catheter 12, allowing the clinician to contact the proximal membrane 35 with their fingertips. It should be understood that this design configuration can provide the clinician with direct tactile feedback regarding the tissue structure being contacted by the distal membrane 24 by feeling the shape changes of the proximal membrane 35. In other words, in this example, the clinician can place their fingertips on the proximal membrane 35 (located outside the catheter 12) to feel the changes in the distal membrane 24 (force transmitted through the fluid lumen 22 extending the entire length of the catheter 12).

[0065] Although Figure 4 and Figure 5 The above-described pressure measurements are shown as being made by a single microfluidic unit 20, but it should be understood that each individual microfluidic unit 20 can sense its own force measurements, thereby allowing the entire array of microfluidic units 20 to transmit an array of pressure measurements to the controller 18. The controller 18 is capable of processing the collection of pressure measurements acquired from the microfluidic array and “map” the pressure distribution along the entire outer surface 30 of the distal end of the catheter 12.

[0066] Figure 6 Another example medical device 110 is shown. The medical device 110 may be similar in form and function to the medical device 10 described above. For example, Figure 6 As shown, the distal region 114 of the catheter 112 may include a plurality of microfluidic cells 120 (microfluidic cells 120 may be similar in form and function to the microfluidic cells 20 described above), each of which transitions into a fluid chamber 122 (fluid chamber 122 may be similar in form and function to the fluid chamber 22 described above). As described above with respect to the medical device 10, both the microfluidic cells 120 and the fluid chamber 122 may be filled with an incompressible fluid. In addition, as described above with respect to the medical device 10, the microfluidic cell 20 may include a proximal membrane 124 (at the Figure 6 Not shown, but in Figure 7 ) and the fluid chamber 122 may include a proximal membrane 135 (shown in Figure 6 Not shown, but in Figure 7 shown in ).

[0067] also, Figure 6 The illustrated medical device 110 may include a plurality of optical fibers 126 extending within the catheter 112 (eg, extending within a lumen of the catheter 112 ). Figure 6It is further shown that the distal end 140 of each of the optical fibers 126 can be spaced apart from, but aligned with, the discrete fluid lumen 122. Additionally, each of the optical fibers 126 can extend proximally within the catheter 112, whereby the proximal end of each optical fiber 126 can be coupled to a controller 118 (the controller 118 can be similar in form and function to the controller 18 described above).

[0068] As described above with respect to the medical device 10 , it should be understood that while a portion of the catheter 112 is positioned within the patient's body, the controller 118 may be positioned external to the patient's body.

[0069] Figure 7 A close-up view of a single microfluidic unit 120 is shown. For example, Figure 7 The microfluidic unit 120 is shown to include a distal membrane 124 that extends along the outer surface 30 of the distal region 114 of the catheter 112. It should be understood that in some examples, the distal membrane 124 of the microfluidic unit 120 can be substantially flush with the outer surface 30 of the distal region 14 of the catheter. However, in other examples, it should be understood that the distal membrane 124 can extend radially outwardly outside the outer surface 30 of the distal region 14 of the catheter.

[0070] Figure 7 It is further shown that each microfluidic unit 120 can include a fluid chamber 134 extending radially inward from the outer surface 30 of the distal region 114 of the conduit. In addition, the proximal region of the fluid chamber 134 can transition into the fluid cavity 122. The fluid cavity 122 can continue to extend radially inward within the outer surface 30 of the distal region 114 of the conduit 112. In other words, the fluid chamber 134 and the fluid cavity 122 can be substantially aligned, both extending radially inward from the outer surface 30 of the distal region of the conduit 112.

[0071] in addition, Figure 7 Detailed view of FIG11 shows the distal end 140 of the optical fiber 126 aligned with the proximal membrane 135 of the fluid chamber 122. It should be understood that in some examples, the optical fiber 126 can be designed to emit a light signal 144 from its distal end 140. For example, the controller 118 can include a laser and / or LED light source that can transmit the light signal 144 through the optical fiber 126, whereby the light signal 144 exits the distal end 140 of the optical fiber 126 and travels toward the proximal membrane 135 of the fluid chamber 122. As will be described in more detail below, the light signal 144 exiting the distal end 140 of the optical fiber 126 can strike the proximal membrane 135 and reflect back toward the distal end 140 of the optical fiber 126. The reflected light is illustrated by dashed arrow 146.

[0072] In some cases, the controller 118 may include a light sensor (e.g., a photodiode) that can be designed to measure changes in the light signal 144 reflected back from the optical fiber 126 (e.g., the reflected light can pass through the optical fiber 126 to the photodiode in the controller 118). Additionally, it should be understood that because the light signal 144 is aligned with the proximal membrane 135, the "pattern" of reflected light from the proximal membrane 135 can change in concert with changes in the proximal membrane 135. The photodiode in the controller 118 can sense the changes in the light pattern reflected back from the proximal membrane 135.

[0073] Figure 7 and Figure 8 Together, an example is shown in which a medical device 110 measures pressure and / or force applied to a distal end of the medical device 110 when the medical device 110 contacts an example tissue site 50 within the body. For example, Figure 7 The distal membrane 124 is shown adjacent an exemplary tissue site 50 within a patient (positioned along the outer surface 30 of the medical device 110, as described above). Figure 7 It will be appreciated from the detailed view of FIG1 that the proximal membrane 135 of the fluid chamber 122 has not deformed because the distal membrane 124 has not yet contacted the tissue site 50. As described above, Figure 7 The detailed view also shows the optical fiber 126 emitting an optical signal 144 directed toward the proximal membrane 135 and reflected light from the proximal membrane 135 back toward the optical fiber 126 .

[0074] Figure 8 The diagram illustrates the position of the medical device 110 after the distal end of the medical device 110 has been advanced such that the distal membrane 124 contacts the tissue site 50. Figure 7 and Figure 8 It should be understood that when the distal membrane 124 contacts the tissue site 50, the distal membrane 124 may deform (e.g., the distal membrane 124 may deform as it engages the contours of the tissue site 50). Moreover, because the microfluidic unit 120 and the fluid chamber 122 are filled with an incompressible fluid, changes in the shape of the distal membrane 124 may translate into changes in the proximal membrane 135. For example, Figure 8 The detailed view of shows that the proximal membrane 135 changes shape (eg, expands outward) in response to changes in the distal membrane 124 .

[0075] Furthermore, as described above, changes in the shape of the proximal membrane 135 can alter the pattern of light reflected back into the optical fiber 126. Furthermore, it should be understood that this reflected light can be transmitted along the optical fiber 126 to a light sensor (e.g., a photodiode) located in the controller 118. Furthermore, the light sensor (e.g., a photodiode) can correlate changes in the pattern of reflected light with varying degrees of deformation of the proximal membrane 135. In other words, as the clinician advances the medical device 110 distally, thereby applying increasing forces to the distal membrane 124, the proximal membrane 135 can deflect increasingly in response to the deflection of the distal membrane 124. The photodiode located in the controller 118 can sense (e.g., measure) these increasing forces. Furthermore, the controller 118 can convert the light signals sensed by the photodiode into force (e.g., pressure) measurements corresponding to the forces applied to the microfluidic unit 120 located at the distal end of the catheter 112.

[0076] In some examples, the optical fiber 126 described above may be described as a fiber optic connector 126, whereby the fiber optic connector 126 may be defined as a single fiber that can transmit the optical signal 144 (e.g., an LED signal) from the controller 118 while also being capable of transmitting the reflected optical signal from the proximal membrane 135 to a light sensor (e.g., a photodiode) in the controller 118. However, in other examples, Figure 7 The optical fiber 126 described in may include two separate fibers, where one fiber transmits the light signal 144 from the controller 118 to the proximal membrane, and a second fiber transmits reflected light from the proximal membrane back to a light sensor (eg, a photodiode).

[0077] Additionally, in some cases, the proximal film 135 may include a mirrored surface to increase the reflected light signal. For example, the proximal film 135 may also include more mirrored reflections or more diffuse reflections to increase or decrease its sensitivity.

[0078] Furthermore, the proximal membrane 135 can be translucent or transparent. The incompressible fluid can include particles that reflect light transmitted from the optical fiber 126. For example, the fluid can be an emulsion that can change the optical signal 144 from one of surface variation variability to one of volume variation variability, thereby improving the signal-to-noise ratio and / or signal linearity characteristics.

[0079] Furthermore, in some examples, the diameter and area of ​​the distal membrane 124 and / or the proximal membrane 135 can be customized relative to each other to alter the sensitivity of light detection. Similarly, the thickness and / or elasticity of the distal membrane 124 and / or the proximal membrane 135 can be customized relative to each other to alter the sensitivity of light detection. For example, a thinner distal membrane 124 may be more sensitive to force measurement and thus be used to measure very light contact forces. Conversely, a thicker distal membrane 124 may be used to measure higher contact forces.

[0080] Alternatively, the proximal membrane 135 itself may include a thick "skin" that changes volume in response to changes in the pressure of the incompressible fluid within the fluid cavity 122. For example, the proximal membrane 135 may include a closed-cell foam structure sandwiched between two membrane layers. As the pressure within the fluid cavity 122 increases, the closed-cell foam structure may become thinner. Furthermore, the foam may contain a reflective material that reflects incident light back toward the optical fiber 126. As the thickness of the foam changes in response to changes in pressure, the light collected by the optical fiber 126 changes.

[0081] In another example, the proximal membrane 135 can include a compressible fluid (eg, a gas) sandwiched between two membranes. When the pressure in the fluid cavity 122 changes, the two membranes can move closer together, thereby changing the light reflected and collected by the optical fiber 126.

[0082] In some examples, a dichroic mirror can be deposited on the distal surface of optical fiber 126. This allows a light signal at one wavelength to be reflected from proximal membrane 135 and detected by a first photodiode in controller 18. Additionally, a second light signal at a second wavelength can be directly reflected from optical fiber 126 and detected by a second photodiode. The pressure signal can be calculated as the ratio between the first photodiode measurement and the second photodiode measurement. This approach has the advantage of reducing variability in optical fiber 126 due to light loss caused by curvature and variability in the connections.

[0083] Although Figure 7 and Figure 8 The above-described pressure measurements are shown as being made by a single microfluidic unit 120, but it should be understood that each individual microfluidic unit 120 can sense its own force measurements, thereby allowing the entire array of microfluidic units 120 to transmit an array of pressure measurements to the controller 118. The controller 118 is capable of processing the collection of pressure measurements acquired from the microfluidic array and “map” the pressure distribution along the entire outer surface 30 of the distal end of the catheter 112.

[0084] Figure 9 Another exemplary medical device 210 is shown. The medical device 210 may be similar in form and function to the medical devices 10 / 110 described above. For example, Figure 8 As shown, the distal region 214 of the catheter 212 can include a plurality of microfluidic units 220 (the microfluidic units 220 can be similar in form and function to the microfluidic units 20 / 120 described above), each transitioning into a fluid chamber 222 (the fluid chamber 222 can be similar in form and function to the fluid chamber 22 / 122 described above). As described above with respect to the medical device 10 / 110, both the microfluidic units 220 and the fluid chamber 222 can be filled with an incompressible fluid, whereby contact of a distal membrane located on the microfluidic unit 220 can be transmitted to a proximal membrane located on the fluid chamber 222 via the incompressible fluid.

[0085] in addition, Figure 9 The illustrated medical device 210 may include a camera 252 spaced apart from but aligned with all of the fluid lumens 222. Additionally, a cable 226 may extend proximally within the catheter 212, whereby a distal end of the cable 226 may be coupled to the camera and a proximal end of the cable 226 may be coupled to a controller 218 (the controller 218 may be similar in form and function to the controller 18 / 118 described above).

[0086] As described above with respect to medical device 10 / 110, it should be understood that while a portion of catheter 212 is located within the patient's body, controller 218 may be located externally of the patient.

[0087] As described above, changes in the fluid pressure within the microfluidic unit 220 and the fluid chamber 222 can cause changes in the proximal membrane of the fluid chamber 222. It should also be understood that the physical deformation of each proximal membrane (for each discrete fluid chamber 222) can be sensed and measured by the camera 252. In addition, the physical changes sensed and measured by the camera 252 can be transmitted from the camera 252 to the controller 218. This collection of signals generated and transmitted by the camera 252 can correspond to the entire array of pressure measurements obtained from the microfluidic unit 220. Furthermore, the controller 218 can process the collection of pressure measurements obtained from the microfluidic array to "map" the pressure distribution along the entire outer surface 30 of the distal end of the catheter 212.

[0088] Figure 10 Another exemplary medical device 310 is shown. The exemplary medical device 310 can be similar in form and function to the medical device 10 described above. For example, the medical device 310 can include an array 354 of microfluidic units 320 disposed along a portion of the distal region 314 of a catheter 312. However, as Figure 10 As shown, the array of microfluidic units 320 may be limited to only a specific region of the distal region 314 of the catheter 312. For example, Figure 10 The microfluidic cells are shown as being confined to a rectangular "strip" along the distal region 314. However, this is not intended to be limiting. Rather, it is contemplated that the array of microfluidic cells may be organized in a variety of arrangements along the distal region 314 of the conduit 312.

[0089] As described above, the medical devices described herein can be used to generate a signal output array from a collection of pressure elements (e.g., microfluidic units). It should be understood that in some cases, the medical devices used herein can be pre-calibrated (e.g., calibrated in an outside laboratory before being used in a medical procedure) so that the pressure signals collected in vivo can be characterized based on a variety of different structures that the distal end of the catheter may contact. For example, pre-calibration can allow the medical device to distinguish between soft and elastomeric structures, or hard and non-elastomeric structures, or gel-like structures, liquids, etc.

[0090] Additionally, in some examples, the pressure sensing arrays described herein may be used for acoustic or ultrasonic detection.

[0091] It should be noted that the features of any catheter described with respect to a particular figure and / or embodiment are not limited to that particular example. Rather, it is contemplated that any features or examples disclosed with respect to a single example may be incorporated into any other example disclosed herein.

[0092] The materials of the various components that can be used for guidewires (and / or other guidewires disclosed herein) and the various devices disclosed herein may include those materials commonly associated with medical devices. For simplicity, in the following discussion with reference to guidewires, it is not intended that the devices and methods described herein be limited only to guidewires, as the discussion is applicable to other similar devices disclosed herein.

[0093] The medical device 10, components of the medical device 10, and / or other medical devices (and components thereof) disclosed herein can be made of metals, metal alloys, polymers (some examples of which are disclosed below), metal-polymer composites, ceramics, combinations thereof, or other suitable materials. Some examples of suitable polymers can include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, e.g., available from DuPont), and polyoxymethylene (POM). ), polyether block esters, polyurethanes (e.g., polyurethane 85A), polypropylene (PP), polyvinyl chloride (PVC), polyether esters (e.g., available from DSMEngineering Plastics ), ether or ester based copolymers (e.g., butene / poly(alkylene ether) phthalate and / or other polyester elastomers such as those available from DuPont ), polyamides (e.g. available from Bayer or available from Elf Atochem ), elastomeric polyamides, block polyamide / ethers, polyether block amides (PEBA, for example, sold under the trade name Available), ethylene vinyl acetate copolymer (EVA), silicone, polyethylene (PE), High-density polyethylene, Low-density polyethylene, linear low-density polyethylene (e.g. ), p-polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polypropylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polyterephthalamide (e.g., ), polysulfone, nylon, nylon-12 (e.g., available from EMS American Grilon ), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefins, polystyrene, epoxy resins, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (e.g., SIBS and / or SIBS50A), polycarbonate, ionomers, biocompatible polymers, other suitable materials, or mixtures, combinations, copolymers, polymer / metal composites thereof, etc. In some embodiments, the sheath can be blended with a liquid crystal polymer (LCP).

[0094] Some examples of suitable metals and metal alloys include stainless steel, such as 304V, 304L, and 316LV stainless steel; mild steel; nickel titanium alloys, such as linear elastic and / or superelastic nitinol; other nickel alloys, such as nickel chromium molybdenum alloys (e.g., UNS: N06625, e.g., 625, UNS: N06022, e.g. UNS: N10276, e.g. other alloys, etc.), nickel-copper alloys (e.g., UNS: N04400, e.g. 400, 400, 400, etc.), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035, e.g. etc.), nickel-molybdenum alloys (e.g., UNS: N10665, e.g. ), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, etc.; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS: R30003, e.g. etc.); platinum-rich stainless steel; titanium; combinations thereof; etc.; or any other suitable material.

[0095] In at least some embodiments, part or all of the medical device 10, components of the medical device 10, and / or other medical devices disclosed herein (and their components) may also be doped with, made of, or otherwise include a radiopaque material. A radiopaque material is understood to be a material that is capable of producing a relatively bright image on a fluorescent screen or other imaging technology during a medical procedure. This relatively bright image helps users of the medical device 10, components of the medical device 10, and / or other medical devices disclosed herein (and their components) determine their location. Some examples of radiopaque materials may include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloys, polymer materials loaded with radiopaque fillers, and the like. In addition, other radiopaque marker bands and / or coils may also be incorporated into the design of the medical device 10, components of the medical device 10, and / or other medical devices disclosed herein (and their components) to achieve the same results.

[0096] In some embodiments, a degree of magnetic resonance imaging (MRI) compatibility is imparted to the medical device 10, components of the medical device 10, and / or other medical devices disclosed herein (and components thereof), or portions thereof, disclosed herein may be made of a material that does not substantially distort an image and does not substantially produce artifacts (e.g., gaps in an image). For example, certain ferromagnetic materials may not be suitable because they may produce artifacts in an MRI image. The medical device 10, components of the medical device 10, and / or other medical devices disclosed herein (and components thereof) may also be made of a material that is imageable by an MRI machine. Some materials that exhibit these properties include, for example, tungsten, cobalt-chromium-molybdenum alloys (e.g., UNS: R30003, for example). etc.), nickel-cobalt-chromium-molybdenum alloy (for example, UNS: R30035 such as MP35-N, etc.), nitinol, etc., and others.

[0097] It should be understood that the present disclosure is in many respects illustrative only. Changes may be made in detail, particularly in shape, size, and arrangement of steps, without exceeding the scope of the present disclosure. This may include, within appropriate limits, the use of any feature of an example embodiment in other embodiments. Of course, the scope of the present disclosure is defined by the language in which the appended claims are expressed.

Claims

1. A medical device comprising: a catheter having a proximal region and a distal tip; and an array of sealed chambers disposed along the distal tip, wherein each chamber comprises a distal membrane disposed along an outer surface of the distal tip and a proximal membrane extending radially inward from the outer surface; wherein each proximal membrane is configured to move between a first position and an expanded position in response to a pressure change within the chamber; wherein each of the array of sealed chambers is filled with an emulsion; and wherein the emulsion comprises a plurality of light reflective particles disposed within an incompressible fluid.

2. The medical device of claim 1 , further comprising a plurality of fibers, wherein each fiber has a proximal end and a distal end, wherein the distal end of each fiber is coupled to a pressure sensor aligned with a single proximal membrane, and wherein each pressure sensor is coupled to its corresponding proximal membrane.

3. The medical device of claim 2, wherein each sensor is configured to measure an extent to which the proximal membrane moves between the first position and the expanded position.

4. The medical device according to any one of claims 1 to 3, wherein each of the sealed chamber arrays is filled with an incompressible fluid.

5. The medical device of any one of claims 1-3, wherein the extent to which each proximal membrane expands directly corresponds to the extent of pressure change within the corresponding chamber to which the membrane is connected.

6. The medical device of any one of claims 1-3, wherein each proximal membrane moves from the first position to the expanded position in response to deflection of its corresponding distal membrane.

7. The medical device according to any one of claims 2-3, wherein each pressure sensor is designed to transmit a pressure signal along its corresponding optical fiber, and wherein the pressure signal corresponds to a pressure change in the chamber corresponding to the sensor.

8. The medical device of any one of claims 1-3, wherein each sealed chamber comprises a first lumen in fluid communication with a second lumen, wherein the first lumen has a first diameter and wherein the second lumen has a second diameter different from the first diameter.

9. The medical device of any one of claims 2-3, wherein each fiber of the plurality of fibers comprises an optical fiber.

10. The medical device of claim 9, wherein a distal end of each of the plurality of optical fibers is spaced apart from the proximal membrane, and wherein each of the plurality of optical fibers is configured to transmit a first optical signal to the proximal membrane.

11. The medical device of claim 10, wherein each first optical signal transmitted to its corresponding proximal membrane is reflected back to each corresponding optical fiber, and wherein the reflected optical signal corresponds to movement of each corresponding proximal membrane.

12. The medical device of claim 11, wherein comparing the first light signal to the reflected light signal directly corresponds to a change in pressure of the chamber.

13. A medical device system comprising: processor; a catheter having a proximal region and a distal tip, the proximal region coupled to the processor; a plurality of fluid-tight chambers disposed along the distal tip, wherein each chamber comprises a distal membrane disposed along an outer surface of the distal tip and a proximal membrane extending radially inward from the outer surface; and a plurality of fibers, wherein each fiber has a proximal end and a distal end, wherein each distal end is aligned with a discrete proximal membrane; wherein each proximal membrane is configured to move between a first position and an expanded position in response to a pressure change within the chamber; wherein each of the array of sealed chambers is filled with an emulsion; and wherein the emulsion comprises a plurality of light reflective particles disposed within an incompressible fluid.

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