Force sensor, force sensing catheter, ablation device and interferometry system

Abstract

The present disclosure relates to a force sensor and a force sensing catheter. The force sensor includes: a sensor body; a plurality of optical sensing devices attached to the sensor main body, wherein each optical sensing device comprises a reflection member, an incident optical fiber arranged opposite to the reflection member, and a force sensing cavity defined by the reflection member and the incident optical fiber; the incident optical fiber of at least one of the plurality of optical sensing devices comprises a first incident optical fiber, a second incident optical fiber arranged opposite to the first incident optical fiber, and a temperature sensing cavity defined by the first incident optical fiber and the second incident optical fiber; the first incident optical fiber is suitable for irradiating the second incident optical fiber and collecting at least one part of light reflected from the near end of the second incident optical fiber, and is suitable for irradiating the reflecting component and collecting at least one part of light reflected from the near end of the reflecting component; the sensor main body is configured in a way that the size of the cavity length of at least one force sensing cavity is changed so as to respond to the force applied to the sensor main body.

Description

Technical Field

[0001] This disclosure relates to the field of medical devices, and more specifically to a force sensor that is particularly suitable for catheter-based diagnostic and therapeutic systems. This disclosure also relates to a force-sensing catheter with a force sensor and an ablation device. Background Technology

[0002] Atrial fibrillation (AF) is one of the most common arrhythmias in clinical practice, with a prevalence of 0.4% to 1% in the general population. Its incidence increases significantly with age, and it can lead to high rates of disability and mortality. Catheter ablation can cure AF and improve patient symptoms. However, the effectiveness of ablation is closely related to the degree of contact between the ablation catheter and the atrial tissue. Permanent transmural damage at all ablation sites is crucial for ensuring a high success rate and reducing recurrence, and it is also a major challenge in ablation. Therefore, improving the accuracy of force sensor measurements is essential, as current force sensors are significantly affected by temperature.

[0003] The aim is to provide a force sensor that reduces the effects of temperature while maintaining high accuracy in force measurement. Summary of the Invention

[0004] In response to the problems and needs mentioned above, this disclosure proposes a force sensor that solves the aforementioned problems and brings other technical benefits by adopting the following technical features.

[0005] This disclosure discloses a force sensor, comprising: a sensor body; an optical sensor element attached to the sensor body, the optical sensor element including a reflective member, an incident optical fiber disposed opposite to the reflective member, and a force sensing cavity defined by the reflective member and the incident optical fiber; the incident optical fiber of the optical sensor element including a first incident optical fiber, a second incident optical fiber disposed opposite to the first incident optical fiber, and a temperature sensing cavity defined by the first incident optical fiber and the second incident optical fiber, the first incident optical fiber being adapted to irradiate the second incident optical fiber and collect at least a portion of light reflected from the proximal end of the second incident optical fiber, and adapted to irradiate the reflective member and collect at least a portion of light reflected from the proximal end of the reflective member; the sensor body is configured such that the length of at least one of the force sensing cavities changes in response to a force applied to the sensor body.

[0006] In one embodiment, the coefficient of thermal expansion of the reflective element is 2-4 times that of the sensor body.

[0007] In one embodiment, the difference in length between the force sensing cavity and the temperature sensing cavity is greater than 1.5 micrometers.

[0008] In one embodiment, the sensor body includes a first segment and a second segment defining a gap therebetween, the gap being bridged by a connecting segment; at least a portion of the outer surface of the connecting segment is recessed inward relative to the outer surfaces of the first segment and the second segment to form the gap between the first segment and the second segment; at least one end of the connecting segment is connected to the first segment or the second segment via an annular portion, the annular portion defining at least a portion of the axial boundary of the gap, the thickness of the annular portion being less than the width of its annular surface.

[0009] In one embodiment, the annular portion includes a first annular portion and a second annular portion, the first annular portion defining a portion of the axial boundary of the gap and connecting a first end of the intermediate segment to the first segment, and the second annular portion defining a portion of the axial boundary of the gap and connecting a second end of the intermediate segment to the second segment.

[0010] In one embodiment, the annular portion extends in a transverse direction perpendicular to the axial direction, or at an angle between 0 and 15° relative to the transverse direction.

[0011] In one embodiment, the sensor body includes a first segment and a second segment, the first segment and the second segment defining a gap therebetween, the gap being bridged by a connecting segment; the sensor body defines a longitudinal axis, the connecting segment being a plurality of arc-shaped connecting segments with rotational intervals around the longitudinal axis, the plurality of arc-shaped connecting segments being approximately uniformly distributed on a circumference centered on the longitudinal axis.

[0012] This disclosure also provides a force-sensing conduit, comprising: a flexible elongated body having a distal end; and a force sensor according to any of the preceding claims, the force sensor being disposed at the distal end within the flexible elongated body.

[0013] This disclosure also provides an ablation device, including a force sensor or a force sensing catheter as described in any of the preceding claims.

[0014] This disclosure also provides an interferometric measurement system, the interferometric measurement system comprising: a light source for emitting coherent light; a force sensor according to any of the preceding claims, configured to receive the coherent light and form and output modulated light modulated by the force to be measured and the temperature to be measured; and an interferometric demodulation device configured to receive the modulated light and demodulate the modulated light to obtain the interference spectrum of the force sensing cavity and the interference spectrum of the temperature sensing cavity.

[0015] The preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings so that the features and advantages of the present disclosure can be readily understood. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings of the embodiments of this disclosure will be briefly described below. The drawings are merely illustrative of some embodiments of this disclosure and are not intended to limit all embodiments of this disclosure to them.

[0017] Figure 1A , 1B Views 1C and 1D show a force sensor according to a first embodiment of the present disclosure; Figure 2 Views of the sensor body according to a second embodiment of the present disclosure are shown; Figure 3 Views of a sensor body according to a third embodiment of the present disclosure are shown; Figure 4 Views of a sensor body according to a fourth embodiment of the present disclosure are shown; Figure 5 Views of a sensor body according to a fifth embodiment of the present disclosure are shown; Figure 6 Views of a sensor body according to a sixth embodiment of the present disclosure are shown; Figure 7 A partially enlarged view of an optical sensor device according to an embodiment of the present disclosure is shown.

[0018] 100 - Sensor body; 10 - First section; 20 - Second section; 30 - Middle section; 31 - First end of middle section; 32 - Second end of middle section; 33 - Receiving part; 41 - First annular part; 42 - Second annular part; 40 - Gap; 200 - Optical sensor element; 51 - Reflecting member; 51a - Proximal end of reflecting member; 52 - Incident optical fiber; 521 - First incident optical fiber; 522 - Second incident optical fiber; 522a - Proximal end of second incident optical fiber; 522b - Distal end of second incident optical fiber; 523 - Temperature sensing cavity; 53 - Force sensing cavity; 54 - Encapsulating resin. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0020] Compared to the embodiments shown in the accompanying drawings, feasible embodiments within the scope of this disclosure may have fewer components, other components not shown in the drawings, different components, components arranged differently, or components with different connections, etc. Furthermore, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as multiple separate components.

[0021] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, “an” or “a” and similar terms do not necessarily indicate a quantity limitation. Terms such as “comprising” or “including” mean that the element or object preceding the word encompasses the element or object listed following the word and its equivalents, without excluding other elements or objects. Terms such as “connected” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as “upper,” “lower,” “left,” and “right” are used only to indicate relative positional relationships, which may change accordingly when the absolute position of the described object changes.

[0022] First refer to Figures 1A-1D A force sensor according to a first embodiment of this disclosure is described. Figures 1A, 1B, 1C, and 1D show a side view, a perspective view, a cross-sectional view taken along the center plane, and a top view of the force sensor, respectively. It should be noted that features described for any embodiment in this disclosure can also be used in other embodiments without causing contradiction.

[0023] The force sensor includes a sensor body 100 and an optical sensor element 200 held by the sensor body 100. The number of optical sensor elements 200 can be two or more. Each optical sensor element 200 includes a reflective member 51 and an incident optical fiber 52. A plurality of reflective members 51 pass through a first section 10 along the axial direction, and a plurality of incident optical fibers 52 pass through a second section 20 along the axial direction, with the number of incident optical fibers 52 being the same as the number of reflective members 51, thus establishing a one-to-one correspondence between the reflective members 51 and the incident optical fibers 52. Figure 1A-1D The illustrated embodiment exemplifies this situation. One end of each reflective member 51 extends into the gap 40 and is opposite to the end of each incident optical fiber 52 that extends into the gap 40. A force-sensing cavity 53 is defined between the end of the reflective member 51 and the end of the incident optical fiber 52. The reflective member 51 and the incident optical fiber 52 can be attached to the sensor body 100.

[0024] At least one of the plurality of optical sensor devices 200 includes an incident optical fiber 52 comprising a first incident optical fiber 521, a second incident optical fiber 522, and a temperature sensing cavity 523 defined by the first incident optical fiber 521 and the second incident optical fiber 522. The first incident optical fiber 521 and the second incident optical fiber 522 are respectively axially attached to the outer surface of the second segment 20. The end of the first incident optical fiber is disposed opposite to the proximal end 522a of the second incident optical fiber and defines the temperature sensing cavity 523 therebetween; the distal end 522b of the second incident optical fiber is disposed opposite to the proximal end 51a of a reflective member and defines a force sensing cavity 53 therebetween. The first incident optical fiber is adapted to irradiate the second reflective optical fiber and collect at least a portion of the light reflected from the proximal end of the second reflective optical fiber, and is adapted to irradiate the reflective member and collect at least a portion of the light reflected from the proximal end of the reflective member through the reflective member.

[0025] The light emitted from the first incident fiber 521 is partially reflected at the near end 522a of the second incident fiber after passing through the temperature sensing cavity 523. This reflected light is superimposed on the end of the first incident fiber 521 with a portion of the incident light, forming a first portion of modulated light carrying the optical path difference of the temperature sensing cavity 523. A portion of the light is reflected at the far end 522b of the second incident fiber, and another portion is reflected back to the far end 522b of the second incident fiber after passing through the force sensing cavity 53 at the near end 51a of the reflecting member and superimposed, forming a second portion of modulated light carrying the optical path difference of the force sensing cavity. Thus, the modulated light returned from the first incident fiber 521 carries optical path difference information corresponding to the cavity lengths of the force sensing cavity and the temperature sensing cavity. Therefore, demodulation of the temperature sensing cavity and the force sensing cavity can be achieved in the same optical path, reducing the cost of demodulation. Furthermore, the optical sensor device simultaneously measures contact force and temperature, eliminating the need for an additional temperature sensor, and simplifying the structure and manufacturing process.

[0026] When the temperature changes, the sensor body 100 undergoes thermal expansion and contraction, which in turn causes a change in the cavity length of the temperature sensing cavity 523. This, in turn, changes the optical path difference of the temperature sensing cavity 523 carried by the first portion of the modulation light. The change in the cavity length of the temperature sensing cavity 523 can be used to determine the magnitude of the temperature. By measuring the temperature, the error caused by the temperature change in the cavity length of the force sensing cavity can be compensated, thereby improving the measurement accuracy of the force sensor.

[0027] When the sensor is subjected to force, deformation occurs between the first section 10 and the second section 20 at the annular portion, causing a change in the distance between the distal end 522b of the second incident optical fiber and the proximal end 51a of the reflective member, i.e., the cavity length of the force sensing cavity. This change in cavity length can be used to determine the magnitude and direction of the force applied to the sensor.

[0028] The present invention is mainly implemented as a miniature sensor, such as a force sensor with a length of 2-5 mm, a first segment 10 with a length of 1-2 mm, a second segment 20 with a length of 1-2 mm, and a gap 40 of 0.1-1 mm. The position of the temperature sensing cavity 523 on the incident optical fiber 52 is not limited, that is, the length of the second incident optical fiber 522 is not limited.

[0029] Since the cavity lengths of the temperature sensing cavity and the force sensing cavity are demodulated in the same demodulation device, the interference spectra of the two cavities need to differ. Therefore, the difference in cavity length between the temperature sensing cavity 523 and the force sensing cavity 53 is greater than 1 micrometer. More preferably, the difference in cavity length between the temperature sensing cavity 523 and the force sensing cavity 53 is greater than 1.5 micrometers. This allows the temperature sensing cavity to have higher temperature sensitivity, while simultaneously enabling demodulation of both the temperature sensing cavity and the force sensing cavity in the same demodulation device. The larger the measurement range of the temperature sensing cavity 523, the greater the change in its cavity length due to temperature variations; therefore, a greater difference in cavity length between it and the force sensing cavity is required. The cavity lengths of the temperature sensing cavity 523 and the force sensing cavity 53 only need to be within the measurement range of the demodulation device.

[0030] The optical sensor 200 can be housed in the receiving portion 33. In some embodiments, the receiving portion 33 can be a through-hole, such as a circular, elliptical, polygonal, square, rectangular, or irregularly shaped through-hole. In other embodiments, the receiving portion 33 can be a groove open to the outer surface of the sensor body 100, and the cross-sectional shape of the groove can be composed of arcs, curves, straight lines, and combinations of curves. Figure 5 As shown, both the first segment 10 and the second segment 20 have three receiving portions 33, and for any segment, the three receiving portions 33 are evenly arranged near the circumference. The first incident optical fiber 521, the second incident optical fiber 522, and the reflective member 51 can be fixed to the sensor body 100 by pasting or welding.

[0031] The sensor body 100 includes a first segment 10, a second segment 20, and an intermediate segment 30 located between the first segment 10 and the second segment 20 and connecting the first segment 10 and the second segment 20. In this disclosure, the first segment 10 may also be referred to as the distal end of the force sensor, and the second segment 20 may also be referred to as the proximal end of the force sensor. Each of the first segment 10, the second segment 20, and the intermediate segment 30 is preferably a hollow cylindrical structure enclosed by sidewalls, particularly a cylindrical structure with an annular cross-section.

[0032] The outer surface of the intermediate section 30 is recessed inward relative to the outer surface of the first section 10 and the outer surface of the second section 20 to form a gap 40 between the first section 10 and the second section 20. When a force is applied to the distal end of the force sensor, i.e., at the location of the first section 10, the first section 10 deforms relative to the second section 20, thereby changing the axial dimension of the gap 40.

[0033] The sensor body 100 also includes at least one annular portion. For example... Figure 1C As shown, the sensor body includes a first annular portion 41 and a second annular portion 42, which define two axial boundaries of the gap 40. The first annular portion 41 connects the first end 31 of the intermediate section 30 to the first section 10, and the second annular portion 42 connects the second end 32 of the intermediate section 30 to the second section 20. In this disclosure, the first annular portion 41 and the second annular portion 42 can be collectively referred to as the annular portion. In this disclosure, the annular portion is a thin-walled structure, that is, its thickness is less than the width of its annular surface.

[0034] The following reference Figures 2-5 The sensor body according to other embodiments of the present disclosure is described. In these embodiments, the arrangement of the first section 10, the second section 20, and the intermediate section 30 is similar to that of the first embodiment. The main difference between these embodiments and the first embodiment lies in the specific shape of the annular portion.

[0035] like Figure 2 As shown, the annular portion has a non-uniform wall thickness. Specifically, in a cross-sectional view along the central plane of the sensor body 100, the annular portion has a right-angled trapezoidal shape. The wall thickness is thinner closer to the central axis of the sensor body and thicker further away from the central axis.

[0036] like Figure 3 As shown, the annular portion has a parallelogram shape. The first annular portion 41 and the second annular portion 42 form an acute angle with respect to the lateral direction of the sensor body 100. This acute angle is preferably less than 30°, more preferably less than 15°. By allowing the annular portion to have a tilt angle controlled within a certain range, it can be ensured that the deformation of the first segment 10 relative to the second segment 20 mainly occurs in the annular portion.

[0037] like Figure 4 As shown, in a cross-sectional view along the central plane of the sensor body 100, the first annular portion 41 and the second annular portion 42 have irregular shapes. The first annular portion 41 and the second annular portion 42 are not flat thin walls, but rather have annular surfaces composed of curved surfaces. In this embodiment, the size of the gap 40 increases in the direction away from the central axis, and the two axial sides of the gap 40 are defined by curves.

[0038] like Figure 5As shown, this embodiment has only one annular portion, namely the first annular portion 41. The second segment 20 is directly connected to the intermediate segment 30, and the first segment 10 is connected to the intermediate segment 30 through the annular portion. It is understood that, in embodiments not shown, the first segment 10 can be directly connected to the intermediate segment 30, and the second segment 20 can be connected to the intermediate segment 30 through the annular portion. Furthermore, in embodiments not shown, the second segment can be configured to have an outer diameter smaller than the outer diameter of the first segment, or even equal to the outer diameter of the intermediate segment 30.

[0039] like Figure 6 As shown, the sensor body 100 includes a first section and a second section, which are bridged by a plurality of connecting segments located in a gap. These connecting segments are compressible along the longitudinal axis, such that the size of the gap 40 changes in response to changes in the force applied to the sensor body. The plurality of connecting segments are approximately uniformly distributed on a circumference centered on the longitudinal axis. The compressible connecting segments can be, for example, springs, arc-shaped connecting segments, or polygonal connecting segments.

[0040] In various implementations, the sensor body is made of a metallic material such as titanium, while the incident optical fiber is made of a highly transparent material such as silica or sapphire. These materials have fundamentally different coefficients of thermal expansion (CTE), with silica having a CTE ranging from 1 to 2 × 10⁻⁶. -6 The coefficient of thermal expansion of titanium is in the range of m / mK (1 to 2 μ / K), while the coefficient of thermal expansion of titanium exceeds 8 μ / K. The difference in the coefficients of thermal expansion will cause a considerable degree of thermally induced change in the cavity length of the force sensing cavity 53.

[0041] The sensor body 100 changes proportionally to the coefficient of thermal expansion of the metallic material. Therefore, for a specific temperature change, the total distance between the potting compound 54 of the incident optical fiber 52 and its paired reflective member 51 changes proportionally to the coefficient of thermal expansion of the metallic material. Simultaneously, the free length L... F and L R The coefficients of thermal expansion of the reflective component 51 and the incident optical fiber 52 will change proportionally.

[0042] (1+αM·ΔT)·LTOT–(1+αF·ΔT)·LF-(1+αR·ΔT)·LR=δ Where α is the coefficient of thermal expansion, ΔT is the local temperature change, δ is the cavity length of the force sensing cavity 53, and the subscripts M, F, and R specify the sensor body, incident optical fiber, and reflective component, respectively. M ·ΔT M ·L TOT The length variation between the potting compound 54 is attributed to the temperature change of the sensor body, while the quantity α F ·ΔT F·L F and α R ·ΔT R ·L R The length changes of the incident fiber 52 and the extended portion of the reflecting member 51 are caused by their respective temperature changes.

[0043] Thus, for a specific total temperature change ΔT, the thermally induced change in the cavity length change Δδ of the force-sensing cavity is approximately: Δδ=αM·ΔT·LTOT–αF·ΔT·LF-αR·ΔT·LR In one embodiment, the thermal expansion coefficient α of the reflective component R and the free length L of the reflecting component R The error caused by temperature changes in the force sensing cavity is compensated for, thereby reducing the error. This error is then further compensated by adjusting the measured temperature of the temperature sensing cavity, thus improving measurement accuracy. This is achieved by adjusting the thermal expansion coefficient α of the reflective component. R and the free length L of the reflecting component R The choice of [specific element] results in the thermal expansion coefficient α of the reflective component being [specifically determined]. R With free length L R The product of the thermal expansion coefficient α of the sensor body is close to that of the sensor body. M With L TOT The product of the lengths of the two components reduces the change in cavity length Δδ of the force sensing cavity 53, thereby reducing the thermally induced change of the force sensing cavity 53. Preferably, the coefficient of thermal expansion of the reflective component is 2-4 times that of the sensor body. This further reduces the thermally induced change of the force sensing cavity.

[0044] Figure 7 The reflective member 51 is depicted as having a free length L R It is defined as the distance between the proximal end 51a of the reflective member and the adhesive on which the reflective member 51 is attached to the receiving portion 33. In one embodiment, the sensor body is made of a metallic material such as titanium, and the reflective member is made of stainless steel.

[0045] This disclosure also provides an interferometric measurement system, comprising: a light source that emits coherent light; the aforementioned sensor configured to receive the coherent light and to form and output modulated light modulated by the force and temperature to be measured; and an interferometric demodulation device configured to receive the modulated light and demodulate the modulated light to obtain the interference spectrum of the force sensing cavity and the interference spectrum of the temperature sensing cavity.

[0046] The interference demodulation device includes: a condenser configured to receive modulated light; a first polarizer disposed downstream of the condenser and having a first polarization direction; a second polarizer disposed downstream of the first polarizer and having a second polarization direction perpendicular or parallel to the first polarization direction; and a birefringent element located between the first polarizer and the second polarizer and having an optical axis at 45° or -45° to the first polarization direction.

[0047] The cavity length demodulation process is as follows: Light emitted from a light source (such as a white LED, xenon lamp, or halogen lamp) is coupled into an optical fiber and enters a coupler or optical circulator. It is then transmitted from the other end of the optical fiber to the sensor. The light signal reflected back from the sensor passes through the coupler again and enters the interference demodulation device. The incoming light beam, after passing through the first polarizer, forms a line beam, which is incident on a birefringent optical wedge. The line beam undergoes equal-thickness interference on the upper and lower surfaces of the wedge. The interference spectrum of the force-sensing cavity is obtained at the position where the thickness of the wedge is equal to the cavity length of the force-sensing cavity, and the interference spectrum of the temperature-sensing cavity is obtained at the position where the thickness of the birefringent optical wedge is equal to the cavity length of the temperature-sensing cavity. As mentioned above, demodulation of the temperature-sensing cavity and the pressure-sensing cavity is achieved in the same channel of the demodulation device, that is, demodulation of the temperature-sensing cavity and the force-sensing cavity is achieved in the same optical path of the demodulation device. For example, the light signals reflected back from the sensor, modulated by the force and temperature to be measured, pass sequentially through the same polarizer and birefringent element in the same optical fiber to obtain the interference spectra of the force-sensing cavity and the temperature-sensing cavity.

[0048] When force and / or temperature change acting on the sensor body, the length of the force sensing cavity and / or the temperature sensing cavity changes, altering the position of the interference spectrum of the force sensing cavity and / or the temperature sensing cavity, thereby calculating the magnitude of the force and temperature. The interferometric measurement system disclosed herein can demodulate both the force sensing cavity and the temperature sensing cavity using the same demodulation device, and its structure and manufacturing process are simple and low-cost.

[0049] This disclosure also provides a force-sensing catheter, in which one or more of the various types of end effectors known in the art for the diagnosis or treatment of blood vessels or organs, such as mapping electrodes or ablation electrodes, can be used. For example, the force-sensing catheter can be configured as an electrophysiological catheter to perform cardiac mapping and ablation.

[0050] The force sensor in any embodiment of this disclosure may be disposed in a force-sensing catheter having a flexible, elongated body with a distal end, the force sensor being disposed at the distal end within the flexible, elongated body. The force sensor compresses or bends in response to contact forces applied to the distal end of the flexible, elongated body, such as contact forces generated when the distal end contacts the wall of a blood vessel or organ. The force-sensing catheter may have a width and length suitable for insertion into a human blood vessel or organ. The force-sensing catheter may include a proximal portion, a middle portion, and a distal portion, the distal portion of which may include an end effector housing the force sensor. End effectors such as those known in the art for the diagnosis or treatment of blood vessels or organs, such as mapping electrodes or ablation electrodes, may be used in this invention. For example, the force-sensing catheter may be configured as an electrophysiological catheter to perform cardiac mapping and ablation. In other embodiments, the force-sensing catheter may be configured to deliver a drug or bioactive agent to the wall of a blood vessel or organ, or to perform minimally invasive procedures such as transmyocardial revascularization or cryoablation. The specific structure of the force sensing conduit used in the force sensor disclosed herein is not limited, depending on the application. The force sensing conduit may be a hollow structure (i.e., having an inner lumen) or a non-hollow structure (i.e., without an inner lumen).

[0051] The force sensor in any embodiment of this disclosure can be disposed in the ablation device. Additionally, the force-sensing catheter in any embodiment of this disclosure can be disposed in the ablation device, or the force-sensing catheter itself can serve as an ablation device. The ablation device can be used to treat diseases such as atrial fibrillation, supraventricular tachycardia, ventricular tachycardia, and cardiac tumors.

[0052] The ablation device may include a catheter for delivering energy (such as radiofrequency energy, cryotherapy energy, etc.) to a specific area of ​​the heart. A force sensor may be mounted, for example, at the catheter tip, to monitor the contact force between the catheter and the heart tissue in real time. This monitoring helps ensure adequate contact between the catheter and the target tissue, improving the ablation effect.

[0053] The exemplary implementation of the solution proposed in this disclosure has been described in detail above with reference to preferred embodiments. However, those skilled in the art will understand that various modifications and alterations can be made to the above specific embodiments without departing from the spirit of this disclosure, and various combinations can be made to the various technical features and structures proposed in this disclosure without exceeding the protection scope of this disclosure, which is determined by the appended claims.

Claims

1. A force sensor, characterized in that, include: Sensor body; Multiple optical sensor elements are attached to the sensor body. Each optical sensor element includes a reflective member, an incident optical fiber disposed opposite to the reflective member, and a force sensing cavity defined by the reflective member and the incident optical fiber. The incident optical fiber of at least one of the plurality of optical sensor devices includes a first incident optical fiber, a second incident optical fiber disposed opposite to the first incident optical fiber, and a temperature sensing cavity defined by the first incident optical fiber and the second incident optical fiber, the first incident optical fiber being adapted to irradiate the second incident optical fiber and collect at least a portion of the light reflected from the proximal end of the second incident optical fiber, and being adapted to irradiate the reflective member and collect at least a portion of the light reflected from the proximal end of the reflective member. The sensor body is configured such that the length of at least one of the force-sensing cavities changes in response to a force applied to the sensor body.

2. The force sensor as described in claim 1, characterized in that, The coefficient of thermal expansion of the reflective component is 2-4 times that of the sensor body.

3. The force sensor as described in claim 1, characterized in that, The difference in length between the force sensing cavity and the temperature sensing cavity is greater than 1.5 micrometers.

4. The force sensor as described in claim 1, characterized in that, The sensor body includes a first section and a second section, the first section and the second section defining a gap therebetween, the gap being bridged by a connecting section; At least a portion of the outer surface of the connecting segment is recessed inward relative to the outer surface of the first segment and the outer surface of the second segment to form the gap between the first segment and the second segment; At least one end of the connecting segment is connected to the first segment or the second segment via an annular portion, the annular portion defining at least a portion of the axial boundary of the gap, and the thickness of the annular portion being less than the width of its annular surface.

5. The force sensor as described in claim 4, characterized in that, The annular portion includes a first annular portion and a second annular portion, the first annular portion defining a portion of the axial boundary of the gap and connecting a first end of the intermediate section to the first section, and the second annular portion defining a portion of the axial boundary of the gap and connecting a second end of the intermediate section to the second section.

6. The force sensor as described in claim 4, characterized in that, The annular portion extends in a transverse direction perpendicular to the axial direction, or at an angle between 0 and 15° relative to the transverse direction.

7. The force sensor as described in claim 1, characterized in that, The sensor body includes a first section and a second section, the first section and the second section defining a gap therebetween, the gap being bridged by a connecting section; the sensor body defines a longitudinal axis, the connecting section being a plurality of arc-shaped connecting sections with rotational intervals around the longitudinal axis, the plurality of arc-shaped connecting sections being approximately uniformly distributed on a circumference centered on the longitudinal axis.

8. A force-sensing conduit, characterized in that, include: A flexible, slender body with a distal end; and The force sensor according to any one of claims 1-7 is disposed at the distal end within the flexible elongated body.

9. An ablation device, characterized in that, Includes the force sensor according to any one of claims 1-7 or the force sensing conduit according to claim 8.

10. An interferometric measurement system, characterized in that, The interferometric measurement system includes: A light source that emits coherent light; The force sensor as described in any one of claims 1-7 is configured to receive the coherent light and to generate and output modulated light modulated by the force to be measured and the temperature to be measured. An interference demodulation device is configured to receive the modulated light and demodulate the modulated light to obtain the interference spectrum of the force sensing cavity and the interference spectrum of the temperature sensing cavity.

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