Intravascular optical device

Abstract

An intravascular device (10) is disclosed. The device includes an elongated member (20), an optical fiber (30), and at least one optical interaction element (40). At least a portion of the elongated member is configured to be inserted into a portion of a patient's vasculature. At least a portion of the optical fiber is located within the elongated member. The optical fiber is configured to transmit optical wavelength radiation. The intravascular device is configured to emit the optical wavelength radiation out of the elongated member in at least two beams of radiated light to be scattered and / or reflected by the portion of the vasculature. The emission of the at least two beams of radiated light includes an interaction of the transmitted optical wavelength radiation with the at least one optical interaction element. The intravascular device is configured to collect at least some of the scattered and / or reflected optical wavelength radiation and couple the at least some of the scattered and / or reflected optical wavelength radiation into the optical fiber, including utilization of the at least one optical interaction element.

Description

Technical Field

[0001] This invention relates to intravascular devices, intravascular microcatheters and guidewire devices, intravascular research systems, methods for conducting intravascular research using intravascular research systems, and computer program units. Intravascular devices may be, for example, guidewires, catheters, or microcatheters. Background Technology

[0002] The general background of this invention is blood clots, and in particular, it provides information to support the management of blood clots, for example, by thrombolysis or thrombectomy. Ischemic stroke is a common cause of death and a leading cause of acquired neurological disability in developed countries. In high-income countries, the number of individuals expected to be affected by stroke is expected to increase significantly due to increased life expectancy.

[0003] WO 2016 / 205576 A1 describes a beam-shaping optical system suitable for use with optical coherence tomography, the system having a beam-shaping insert made of a polymer material, the insert integrally defining a beam-shaping element. The beam-shaping element has a reflective element positioned on a curved surface. A light source generates an electromagnetic beam. An optical fiber has a core and a cladding, a first end optically coupled to the light source, and an optical fiber end. The optical fiber end is configured to emit the electromagnetic beam toward the beam-shaping element. The reflective element has a reflectivity greater than approximately 98% for both a first wavelength band and a second wavelength band of the electromagnetic beam.

[0004] Thrombectomy (i.e., the physical removal of blood clots) has proven superior to thrombolysis in the management of acute stroke. This has spurred the development of various thrombectomy devices. Currently available devices include stent retrieval devices such as the Embotrap from Johnson & Johnson, the Trevo ProVue from Stryker, the Solitaire from Covidien, and the Penumbra series of aspiration thrombectomy devices from Penumbra. Achieving correct treatment on the first attempt in thrombectomy is crucial because the time window available for treatment is very short. Choosing the wrong treatment device will require additional attempts to remove the blood clot, thus prolonging the procedure time. Each thrombectomy attempt takes 5 to 10 minutes. Therefore, choosing the wrong device and needing to use different devices subsequently leads to an increase in medical complications and treatment costs.

[0005] The complexity of thrombectomy lies in the fact that blood clots have different compositions. These components pose different risks during thrombectomy: see, for example, T. Andersson's "The Importance of Clot Properties in Endovascular Stroke Therapy" (…). https: / / neuronewsinternational. com / the- importance-of-clot-properties-in-endovascular-stroke-therapy /

[0006] (2015). The problems include the following: i) Red blood cell-rich clots may be fragile and at risk of clot rupture; ii) Fibrin-rich clots may have a viscosity that makes them difficult to grasp with thrombectomy equipment; iii) Approximately 15% of clots resist thrombectomy.

[0007] The ability to determine which treatment device to use for blood clots is also advantageous for peripheral venous clots. Peripheral venous clots differ in composition from clots that can lead to ischemic stroke. If left untreated or treated with the wrong device, a moving peripheral venous blood clot may, for example, be transported to the lungs and trigger further medical complications.

[0008] Therefore, for both peripheral venous clots and clots that could potentially trigger a stroke, it is advantageous for physicians to know the composition of the blood clot before selecting a thrombectomy device. Thus, these and other related issues need to be addressed. Summary of the Invention

[0009] Having improved instruments to support intravascular studies would be advantageous.

[0010] The object of the present invention is achieved by means of the subject matter of the independent claims, wherein further embodiments are included in the dependent claims. It should be noted that the aspects and examples described below are applicable to intravascular devices, intravascular microcatheters and guidewire devices, intravascular research systems, methods for intravascular research, as well as computer program units and computer-readable media.

[0011] According to a first aspect, an intravascular device is provided, comprising:

[0012] Slender components;

[0013] Fiber optics; and

[0014] At least one optical interaction element;

[0015] At least a portion of the elongated member is configured to be inserted into a portion of a patient's vascular system. At least a portion of the optical fiber is located within the elongated member. The optical fiber is configured to transmit optical wavelength radiation. The intravascular device is configured to emit optical wavelength radiation from the elongated member in at least two radiation beams, so as to be scattered and / or reflected by a portion of the vascular system. The emission of the at least two radiation beams includes the interaction of the transmitted optical wavelength radiation with the at least one optical interaction element. The intravascular device is configured to collect at least some of the scattered and / or reflected optical wavelength radiation and couple the at least some of the scattered and / or reflected optical wavelength radiation into the optical fiber, including the utilization of the at least one optical interaction element.

[0016] Intravascular devices can be used with optical radiation sources that generate broadband optical radiation. Broadband optical radiation can be provided by simultaneously utilizing a broadband light source, or by scanning a narrowband filter across the output of the broadband light source, or by scanning the wavelengths of a monochromatic optical radiation source at multiple wavelengths, such that the broadband optical radiation is coupled into and transmitted via an optical fiber. The optical radiation then exits the intravascular device and interacts with the patient's vascular system. Optical radiation reflected and / or scattered from, for example, blood clots can be presented to a detection unit, such as an optical detector or spectrometer. By arranging at least two radiation beams emanating from the interventional device, different regions of the vascular structure can be interrogated using the interventional device in a fixed position. Furthermore, the at least two radiation beams can optionally use different optical wavelengths to interrogate their corresponding regions. In one embodiment, a first forward-looking radiation beam emanating optical wavelengths in the axial direction relative to the distal end of the interventional device can be provided, and a second side-looking radiation beam emanating or projecting optical wavelengths radially outward relative to the longitudinal axis of the interventional device can be provided. Thus, as the interventional device advances through the vascular system, the first beam can be used to characterize the vascular system before the second beam. Because the optical contact between the blood clot and the interventional device is improved as the device moves past it, the second beam can provide improved optical measurements. Furthermore, by providing two radiating beams (where, for example, one beam extends from the end of the interventional device and the second beam extends from the sidewall of the device), the physician can bend the end of the interventional device (which may be a guidewire) as needed to probe specific areas. The second beam can then extend from the sidewall of the device at a distance from its unbent end, providing accurate measurements as the device slides past the subject being questioned. Two or more radiating beams can be emitted from the sidewall of the interventional device, or practically, two or more beams can be projected from the front of the device. These beams can overlap but include different wavelength ranges. Different wavelength ranges can be provided through appropriate scanning or switching, or they can have different angular orientations and have the same or different wavelength ranges.

[0017] In the example, the at least two radiation beams include a first radiation beam emitted from the sidewall of the elongated member.

[0018] In the example, the at least two radiation beams include a second radiation beam emitted from the sidewall of the elongated member.

[0019] In the example, the wavelength range of the first radiated beam is different from the wavelength range of the second radiated beam.

[0020] In this way, different optical wavelengths can be emitted, and thus, different volumes can be probed optically.

[0021] In the example, the first radiating beam is emitted from the elongated member at a first longitudinal position, and the second radiating beam is emitted from the elongated member at a second longitudinal position different from the first longitudinal position.

[0022] Therefore, for example, a radiation beam with one wavelength range can be emitted laterally from the intravascular device, and a second radiation beam can be emitted parallel to the first beam but with a second wavelength range and at different locations along the length of the intravascular device (e.g., a guidewire). Then, as the device moves past a blood clot, the blood clot is questioned at one wavelength range and then at the second wavelength range, and the physician does not need to rotate the device but only needs to move it longitudinally. In other words, a radiation beam with one wavelength range can be emitted laterally, for example, 4 cm from the end of the intravascular device, and a second beam can be emitted in the same direction and parallel to the first radiation beam, for example, 5 cm from the end of the intravascular device, but with a different wavelength range.

[0023] In the example, the at least two radiation beams include radiation beams emitted from the end wall of the elongated member.

[0024] Therefore, it can provide a forward-oriented radiation beam.

[0025] In the example, the wavelength range of the first radiated beam is different from the wavelength range of the radiated beam emitted from the end wall of the elongated member.

[0026] In the example, the wavelength range of the second radiated beam is different from the wavelength range of the radiated beam emitted from the end of the elongated member.

[0027] In the example, the at least one optical interaction element includes a wavelength selection element.

[0028] In the example, a portion of the optical fiber at its distal end is fixedly connected to the elongated member. At least a portion of the optical fiber located within the elongated member, excluding the fixed distal end, is not fixedly connected to the elongated member.

[0029] According to a second aspect, an intravascular device is provided, comprising:

[0030] Slender components;

[0031] Fiber optics; and

[0032] At least one optical interaction element.

[0033] At least a portion of the elongated member is configured to be inserted into a portion of a patient's vascular system. At least a portion of the optical fiber is located within the elongated member. The optical fiber is configured to transmit optical wavelength radiation. The intravascular device is configured to emit optical wavelength radiation from the elongated member as a radiating beam, the radiating beam forming an annular emission profile substantially perpendicular to the longitudinal axis of the elongated member, so as to be partially scattered and / or reflected by the vascular system. The emission of the radiating beam includes the interaction of the transmitted optical wavelength radiation with the at least one optical interaction element. The intravascular device is configured to collect at least some of the scattered and / or reflected optical wavelength radiation and couple the at least some of the scattered and / or reflected optical wavelength radiation into the optical fiber, including the utilization of the at least one optical interaction element.

[0034] Therefore, the intravascular device emits and collects optical wavelength radiation at the same longitudinal position or location, from / to different angles surrounding the slender member. In this way, interventional physicians do not need to twist or rotate the guidewire in the longitudinal position to inquire about blood clots, because the optical wavelength radiation is emitted at all angles around the intravascular device at that location.

[0035] According to a third aspect, an intravascular microcatheter and guidewire device is provided, comprising:

[0036] Microcatheters; and

[0037] According to the intravascular device of the first aspect or according to the intravascular device of the second aspect.

[0038] At least a portion of the microcatheter is configured to be inserted into a portion of the patient's vascular system. The microcatheter includes at least one light-transmitting wall portion. The endovascular device is configured to slide within the microcatheter along its longitudinal axis. The microcatheter and the endovascular device are configured such that when the endovascular guidewire is positioned at one or more longitudinal locations along the longitudinal axis of the microcatheter, optical wavelength radiation is emitted from the microcatheter through the at least one light-transmitting wall portion, and scattered and / or reflected optical wavelength radiation enters the microcatheter through the at least one light-transmitting wall portion.

[0039] According to the fourth aspect, an intravascular research system is provided, comprising:

[0040] According to the intravascular device of the first aspect, or according to the intravascular device of the second aspect, or according to the intravascular microcatheter and guidewire device of the third aspect;

[0041] Optical radiation source;

[0042] Optical radiation detectors; and

[0043] Processing unit.

[0044] The optical radiation source is configured to generate optical wavelength radiation over a broadband range and couple the optical wavelength radiation into the optical fiber. The optical radiation detector is configured to generate at least one detection signal based on the scattered and / or reflected optical wavelength radiation. The processing unit is configured to determine at least one spectral-resolved dataset based on the at least one detection signal. The processing unit is configured to determine information about blood clots based on the at least one spectral-resolved dataset.

[0045] In this way, spectroscopy is used to provide information related to suspected obstructive structures (e.g., blood clots) and to determine their location. By using more than one beam of radiation to probe vascular structures, the location and characteristics of blood clots can be determined more effectively and efficiently. Therefore, it is possible to determine the presence of blood clots, and if present, to differentiate between different types, such as whether the clot is rich in red blood cells, whether it is rich in fibrin, and whether it is the type resistant to thrombectomy and must be treated with thrombolysis.

[0046] In other words, being able to identify the correct thrombectomy device for removing blood clots reduces treatment time, costs, and patient risk by minimizing the need for a second blood clot removal procedure if the wrong type of device is initially selected.

[0047] According to a fifth aspect, a method for performing intravascular studies using the intravascular study system according to the fourth aspect is provided, wherein the method includes:

[0048] The optical radiation source is used to generate optical wavelength radiation over a wide bandwidth.

[0049] Broadband optical wavelength radiation is coupled into the optical fiber of the intravascular device or the intravascular microcatheter and guidewire device;

[0050] The intravascular device or the intravascular microcatheter and guidewire device is used to collect scattered and / or reflected optical wavelength radiation from the patient's vascular structures;

[0051] The optical radiation detector generates at least one detection signal based on the scattered and / or reflected optical wavelength radiation;

[0052] The processing unit determines at least one spectral-resolved dataset based on the at least one detection signal; and

[0053] The processing unit determines information about the blood clot based on the at least one spectral resolution dataset.

[0054] According to another aspect, a computer program unit is provided for controlling the aforementioned device and / or system, wherein if the computer program unit is executed by a processing unit, the computer program unit is adapted to perform the steps of the aforementioned method.

[0055] According to another aspect, a computer-readable medium is provided on which the computer unit as described above has been stored.

[0056] According to a sixth aspect, a system for determining the composition of a peripheral venous clot using the system, a corresponding method for determining the composition of a peripheral venous clot using the system, and a corresponding computer program product are provided.

[0057] The system for determining the composition of peripheral venous clots includes:

[0058] An intravascular device for determining the composition of blood clots in a peripheral vascular system, the intravascular device comprising:

[0059] Slender components; and

[0060] optical fiber;

[0061] In this embodiment, at least a portion of the elongated member is configured to be inserted into a portion of the patient's vascular system;

[0062] Wherein, at least a portion of the optical fiber is located within the elongated member;

[0063] The optical fiber is configured to transmit optical wavelength radiation;

[0064] The intravascular device is configured to emit a portion of the optical wavelength radiation from the elongated member so that it may be partially scattered and / or reflected by the vascular system.

[0065] The intravascular device is configured to: collect at least some of the scattered and / or reflected optical wavelength radiation, and couple the at least some of the scattered and / or reflected optical wavelength radiation into the optical fiber; and the system further includes:

[0066] Optical radiation source;

[0067] Optical radiation detectors; and

[0068] Processing unit;

[0069] The optical radiation source is configured to generate optical wavelength radiation over a broadband range and couple the optical wavelength radiation into the optical fiber;

[0070] The optical radiation detector is configured to generate at least one detection signal based on the scattered and / or reflected optical wavelength radiation.

[0071] The processing unit is configured to determine at least one spectral resolution dataset based on the at least one detection signal;

[0072] Wherein, the at least one spectral resolution dataset includes spectra corresponding to collagen; and

[0073] The processing unit is configured to: determine the collagen content based on the spectrum corresponding to collagen, and determine information about blood clots based on the collagen content.

[0074] The corresponding method for determining the collagen content of peripheral vascular clots using the aforementioned intravascular study system for determining the composition of blood clots in the peripheral vascular system may include the following steps:

[0075] The optical radiation source is used to generate optical wavelength radiation over a wide bandwidth.

[0076] Broadband optical wavelength radiation is coupled into the optical fiber of the intravascular device or the intravascular microcatheter and guidewire device;

[0077] The intravascular device or the intravascular microcatheter and guidewire device is used to collect scattered and / or reflected optical wavelength radiation from the patient's vascular structures;

[0078] The optical wavelength radiation detector generates at least one detection signal based on the scattered and / or reflected optical wavelength radiation;

[0079] The processing unit determines at least one spectral-resolved dataset based on the at least one detection signal, the at least one spectral-resolved dataset including spectra corresponding to collagen; and

[0080] The processing unit determines the collagen content based on the spectrum corresponding to collagen, and determines information about blood clots based on the collagen content.

[0081] A corresponding computer program product is also provided, the computer program product including instructions that, when executed by a processor, cause the processor to perform the method.

[0082] Advantageously, the benefits provided by any one of the foregoing aspects apply equally to all other aspects, and vice versa.

[0083] The above aspects and examples will be apparent and illustrated with reference to the embodiments described below. Attached Figure Description

[0084] Exemplary embodiments will be described below with reference to the following figures:

[0085] Figure 1 A schematic example of an intravascular device is shown;

[0086] Figure 2 A schematic example of an intravascular microcatheter and guidewire device and an intravascular research system is shown;

[0087] Figure 3 This demonstrates the method used in intravascular studies;

[0088] Figure 4 A diffuse reflectance spectroscopy (DRS) system for blood clot identification is shown;

[0089] Figure 5 A prior art tissue sensing guidewire is shown, wherein sensing occurs at the tip of the guidewire;

[0090] Figure 6 An example of an intravascular guidewire is shown;

[0091] Figure 7 An example of an intravascular guidewire is shown;

[0092] Figure 8 Examples of intravascular microcatheters and guidewire devices are shown;

[0093] Figure 9 An example of an intravascular guidewire is shown;

[0094] Figure 10 An example of an intravascular guidewire is shown;

[0095] Figure 11 An example of an intravascular guidewire is shown;

[0096] Figure 12 An example of an intravascular guidewire is shown;

[0097] Figure 13 An example of an intravascular guidewire is shown;

[0098] Figure 14 The figure illustrates the relationship between changes in light intensity (in arbitrary units) and wavelength in nanometers for three simulated blood clot samples; and

[0099] Figure 15 The figure illustrates the relationship between the predictive power (predictor factor) of simulated blood clots for several measurements and the collagen fraction (%). Detailed Implementation

[0100] Figure 1 An example of an intravascular device 10 is shown. The device includes an elongated member 20, an optical fiber 30, and at least one optical interaction element 40. At least a portion of the elongated member is configured to be inserted into a portion of a patient's vascular system. At least a portion of the optical fiber is located within the elongated member. The optical fiber is configured to transmit optical wavelength radiation. The intravascular device is configured to emit optical wavelength radiation from the elongated member in at least two radiation beams so as to be scattered and / or reflected by a portion of the vascular system. The emission of the at least two radiation beams includes the interaction of the transmitted optical wavelength radiation with the at least one optical interaction element. The intravascular device is configured to collect at least some of the scattered and / or reflected optical wavelength radiation and couple the at least some of the scattered and / or reflected optical wavelength radiation into the optical fiber, including the utilization of the at least one optical interaction element.

[0101] In the example, the optical wavelength radiation is generated by an optical radiation source that simultaneously emits broadband optical radiation. Alternatively, in the example, the optical wavelength radiation is generated by an optical radiation source that emits narrowband optical radiation and scans the emitted optical wavelengths over a wavelength range to generate broadband optical radiation transmitted via optical fiber.

[0102] In the example, the at least one optical interaction element includes at least one light-transmitting wall portion 50 of the elongated member, and the emitted optical wavelength radiation is guided out of the elongated member through the at least one light-transmitting wall portion, and a portion of the scattered and / or reflected optical wavelength radiation returns through the at least one light-transmitting wall portion. Therefore, the window can protect the optical fiber and can be a wavelength-sensitive filter, thus providing a convenient way to select the probe wavelength range, and wherein the exit windows for different beams can have different passband wavelength ranges, thus providing an efficient way to provide beams with different wavelength ranges. These windows can be located on the sidewalls of the elongated member, and, if desired, on the endwalls of the elongated member.

[0103] In the example, the intravascular device is a guidewire.

[0104] In the example, the intravascular device is a microcatheter.

[0105] In the example, the elongated member includes a radiopaque marker.

[0106] In the example, the elongated member is a tube.

[0107] In the example, the optical fiber includes a non-transmissive marking.

[0108] In this way, the operator can determine in which direction or in which specific directions the optical wavelength radiation will be emitted in order to maximize the overlap between the blood clot being examined and the spectral sensing volume.

[0109] According to the example, the at least two radiation beams include a first radiation beam emitted from the sidewall of the elongated member.

[0110] In the example, the first radiating beam is emitted from the sidewall of the elongated member at a distance of at least 3 centimeters from the end of the elongated member.

[0111] In the example, the first radiating beam is emitted in a direction perpendicular to the longitudinal axis of the elongated member.

[0112] In the example, the at least one optical interaction element includes a beam splitter.

[0113] In the example, the at least one optical interaction element includes a 45-degree beam splitter.

[0114] In the example, the at least one optical interaction element includes a region in the optical fiber that exhibits total internal reflection.

[0115] In the example, the at least one optical interaction element includes an optical wavelength filter.

[0116] In the example, the at least one optical interaction element includes a fiber Bragg grating.

[0117] According to the example, the at least two radiation beams include a second radiation beam emitted from the sidewall of the elongated member.

[0118] In the example, the second radiating beam is emitted from the sidewall of the elongated member at least 3 centimeters from the end of the elongated member.

[0119] In the example, the second radiating beam is emitted in a direction perpendicular to the longitudinal axis of the elongated member.

[0120] In the example, the at least one optical interaction element includes a beam splitter.

[0121] In the example, the at least one optical interaction element includes a 45-degree beam splitter.

[0122] In the example, the at least one optical interaction element includes a fiber Bragg grating.

[0123] In the example, the at least one optical interaction element includes a wavelength bandpass filter.

[0124] In the example, the at least one optical interaction element includes a wavelength selection window.

[0125] As an example, the wavelength range of the first radiated beam is different from the wavelength range of the second radiated beam.

[0126] According to the example, the first radiating beam is emitted from the elongated member at a first longitudinal position, and the second radiating beam is emitted from the elongated member at a second longitudinal position different from the first longitudinal position.

[0127] According to the example, the at least two radiation beams include radiation beams emitted from the end wall of the elongated member.

[0128] In the example, the radiating beam emitted from the end wall of the elongated member is emitted in a direction parallel to the longitudinal axis of the elongated member.

[0129] According to the example, the wavelength range of the first radiated beam is different from the wavelength range of the radiated beam emitted from the end wall of the elongated member.

[0130] According to the example, the wavelength range of the second radiated beam is different from the wavelength range of the radiated beam emitted from the end of the elongated member.

[0131] According to the example, the at least one optical interaction element includes a wavelength selection element.

[0132] In the example, the at least one wavelength selection element includes a fiber Bragg grating.

[0133] In the example, the at least one wavelength selection element includes a wavelength bandpass filter.

[0134] In the example, the at least one wavelength selection element includes a wavelength selection window. Therefore, the wavelength selection window can be placed in the wall or center of an elongated member, can be placed in the side wall and / or front wall, and provides an efficient way to provide optical wavelength radiation for interrogating the material via optical wavelength radiation having a specific wavelength range that is only transmitted through the element.

[0135] According to the example, a portion of the optical fiber at its distal end is fixedly connected to the elongated member. At least a portion of the optical fiber located within the elongated member, other than the fixed distal end, is not fixedly connected to the elongated member.

[0136] Figure 1Another example of an intravascular device 10 can also be represented. This intravascular device 10 includes an elongated member 20, an optical fiber 30, and at least one optical interaction element 40. At least a portion of the elongated member is configured to be inserted into a portion of a patient's vascular system. At least a portion of the optical fiber is located within the elongated member. The optical fiber is configured to transmit optical wavelength radiation. The intravascular device is configured to emit optical wavelength radiation from the elongated member as a radiating beam, the radiating beam forming an annular emission profile substantially perpendicular to the longitudinal axis of the elongated member, so as to be scattered and / or reflected by a portion of the vascular system. The emission of the radiating beam includes the interaction of the transmitted optical wavelength radiation with the at least one optical interaction element. The intravascular device is configured to collect at least some of the scattered and / or reflected optical wavelength radiation and couple the at least some of the scattered and / or reflected optical wavelength radiation into the optical fiber, including the utilization of the at least one optical interaction element.

[0137] In the example, annular optical wavelength radiation is emitted from the sidewall of the elongated member at a distance of at least 3 cm from the end of the elongated member.

[0138] Therefore, interventional physicians can bend the tip of the guidewire as needed to provide, for example, an exploration beam emerging from the end of the guidewire at the correct angle, without affecting one or more lateral transmission beams.

[0139] In the example, one or more of the at least one optical interaction element are rotationally symmetric about the longitudinal axis of the elongated member.

[0140] In the example, the rotationally symmetric one or more optical interaction elements in the at least one optical interaction element include a tapered structure.

[0141] In the example, the at least one optical interaction element includes at least one light-transmitting wall portion 50 of the elongated member, and the emitted optical wavelength radiation is guided out of the elongated member through the at least one light-transmitting wall portion, and a portion of the scattered and / or reflected optical wavelength radiation returns through the at least one light-transmitting wall portion. Therefore, the window can protect the optical fiber and can be a wavelength-sensitive filter, thus providing a convenient way to select the probe wavelength range, and wherein the exit windows for different beams can have different passband wavelength ranges, thus providing an efficient way to provide beams with different wavelength ranges. These windows can be located on the sidewalls of the elongated member, and, if desired, on the endwalls of the elongated member.

[0142] In the example, the at least one optical interaction element is configured to laterally emit an additional radiating beam from the elongated member at a longitudinal position different from the annular emission profile. The radiating beam can have a smaller angular span than the annular emission profile. Therefore, the annular emission profile (or circular emission) probing can be used to quickly locate the clot, and then the second radiating beam can be moved to that location. Through guidewire rotation, the radiating beam can be used to interrogate the blood clot with a high signal-to-noise ratio because the signal can be confined to the blood clot and does not contain background vascular system information.

[0143] Figure 2 The diagram shows a microcatheter 110 and, as shown above... Figure 1 Examples of the endovascular device 10, including the endovascular microcatheter and guidewire device 100, described in either of the two embodiments. At least a portion of the microcatheter is configured to be inserted into a portion of a patient's vascular system. The microcatheter includes at least one light-transmitting wall portion. The endovascular device is configured to slide within the microcatheter along its longitudinal axis. The microcatheter and the endovascular device are configured such that when the endovascular guidewire is positioned at one or more longitudinal locations along the longitudinal axis of the microcatheter, optical wavelength radiation is emitted from the microcatheter through the at least one light-transmitting wall portion, and scattered and / or reflected optical wavelength radiation enters the microcatheter through the at least one light-transmitting wall portion.

[0144] Figure 3 An example of an intravascular study system 200 is shown. This system includes, as described above... Figure 1 The intravascular device 10 described in either of the two embodiments described, or the intravascular device 100 according to claim 11, or as per [the description of the two embodiments]... Figure 2 The described intravascular microcatheter and guidewire device 100. System 200 also includes an optical radiation source 210, an optical radiation detector 220, and a processing unit 230. The optical radiation source is configured to generate optical wavelength radiation over a broadband range and couple the optical wavelength radiation into the optical fiber. The optical radiation detector is configured to generate at least one detection signal based on the scattered and / or reflected optical wavelength radiation. The processing unit is configured to determine at least one spectrally resolved dataset based on the at least one detection signal. The processing unit is configured to determine information about blood clots based on the at least one spectrally resolved dataset.

[0145] In the example, the optical radiation source is configured to scan narrowband or monochromatic optical wavelength radiation over a broadband area, and the at least one optical radiation signal includes scattered and / or reflected optical radiation for each wavelength step of the scan.

[0146] In the example, the optical radiation source is configured to provide broadband optical wavelength radiation in a single beam, and the detector and the processing unit can be part of a spectrometer that determines the "single-shot" detection signal and the spectral resolution dataset.

[0147] In the example, the processing unit is configured to provide an output indicating the spectrum detected from the blood vessel wall.

[0148] In this way, a feedback loop is provided to the interventional physician, who then knows when no blood clots are detected and can rotate or move the guidewire as needed to detect blood clots.

[0149] Associated with system 200 is a method for conducting intravascular studies using an intravascular study system, the method comprising:

[0150] The optical radiation source is used to generate optical wavelength radiation over a wide bandwidth.

[0151] Broadband optical wavelength radiation is coupled into the optical fiber of the intravascular device or the intravascular microcatheter and guidewire device;

[0152] The intravascular device or the intravascular microcatheter and guidewire device is used to collect scattered and / or reflected optical wavelength radiation from the patient's vascular structures;

[0153] The optical radiation detector generates at least one detection signal based on the scattered and / or reflected optical wavelength radiation;

[0154] The processing unit determines at least one spectral-resolved dataset based on the at least one detection signal; and

[0155] The processing unit determines information about the blood clot based on the at least one spectral resolution dataset.

[0156] Now for reference Figure 4-13 The intravascular devices, intravascular microcatheters and guidewire devices, intravascular research systems, and methods for intravascular research will be described in more detail with reference to specific embodiments.

[0157] Figure 4A diffuse reflectance spectroscopy (DRS) system for blood clot discrimination is illustrated. Studies have shown that, among other optical analysis techniques, DRS can be used to differentiate between different types of blood clots and assist physicians in making optimal treatment decisions. As shown at “A”, a light source emits optical wavelength radiation through an optical fiber. As shown at “B”, the optical wavelength radiation is scattered and absorbed in the blood clot, and the portion of the scattered optical wavelength radiation that returns to the optical fiber is received. As shown at “C”, a spectrometer receives and analyzes the optical wavelength radiation. As shown at “D”, an algorithm calculates physiological parameters, such as red blood cell count, fibrinogen count, and white blood cell count, which are presented to the operator. Therefore, in this system, optical wavelength radiation is used to illuminate the diffuse reflectance sample, which can be, for example, biological tissue. The novel apparatus, systems, and methods described herein are capable of utilizing optical radiation sources that scan narrow emission bands over a wide wavelength range to generate that optical wavelength radiation (e.g., by scanning a wavelength-tunable laser), or capable of having light sources that emit optical wavelength radiation across multiple optical wavelengths, or in fact, capable of consisting of multiple narrow-band light sources (e.g., infrared or visible LEDs or lasers) that emit simultaneously or sequentially. The optical wavelength radiation is scattered and / or absorbed by the sample. A portion of the backscattered optical wavelength radiation is collected and analyzed using an optical detector, thereby generating a spectrum characterizing the sample. Typically, these spectra show a scattering background interrupted by characteristic degradation caused by absorbers such as blood, water, and fat.For example, detailed descriptions of exemplary methods for analyzing data are found in the following publications: R. Nachabé, BHWHendriks, AEDesjardins, M. van der Voort, MB van der Mark, and HJCMSterenborg, “Estimation of lipid and water concentrations in scattering media with diffuse optical spectroscopy from 900 to 1600 nm” (J. Biomed. Opt. 15, 2010); Rami Nachabé, Benno HWHendriks, Marjolein van der Voort, Adrien E. Desjardins, and Henricus JCMSterenborg, “Estimation of biological chromophores using diffuse optical spectroscopy: benefit of extending the UV-VIS wavelength range to include 1000 to 1600 nm” (Optics Express). 18, 2010, p. 1432) and R. Nachabé et al., “Diagnosis of breast cancer using diffuse optical spectroscopy from 500 to 1600 nm: comparison of classification methods” (J. Biomed. Opt. 16(8), p. 087010, 2011).

[0158] Figure 5A prior art tissue-sensing guidewire positioned inside a blood vessel is shown, wherein optical sensing occurs at the tip of the guidewire. The blood vessel and vessel wall are illustrated, with surrounding tissue shown outside the vessel wall. "Non-invasive optical radiation emitting tip" is denoted by "A", "sensing volume" by "B", and "clot" by "C". Such systems are described, for example, in US5439000, US 5601087A, US 7532920 B1, and US 6445939 B1. However, such sensing devices are suboptimal for some of the aforementioned sensing applications for several reasons, including: i) the guidewire tip tends to slide along the vessel wall, which may make it difficult to achieve good optical contact with the blood clot; ii) because the guidewire typically slides along the vessel wall, the sensed volume will include not only the blood clot but also the vessel wall and surrounding tissue, which reduces the signal-to-noise ratio and makes it more difficult to interpret the reflected optical wavelength radiation; iii) some interventional physicians may prefer to use guidewires with specially shaped tips, sometimes shaped by themselves; however, such tips may interfere with the optical radiation at the tip. (iv) Neuropathic guidewires are typically designed with very soft tips to avoid damage to the vascular system, whereas for forward-sensing optical guidewires, the necessary fiber optics would stiffen the tips, thus limiting their softness; (v) Because blood clots can be non-uniform, physicians want to scan along the length of the clot without losing the guidewire's position. This is difficult when sensing occurs at the tip of the guidewire, as the guidewire needs to be completely withdrawn from the clot to sense the proximal portion; (vi) For regulatory, training, or safety reasons, it would be beneficial to have the option to measure the clot composition from within the neurocatheter, so that the measuring guidewire does not need to be in direct contact with the vessel wall or the blood clot.

[0159] Therefore, for existing tissue sensing guidewires, in cases where sensing occurs at the tip of the guidewire (e.g.) Figure 5 As shown, the sensing volume may be suboptimal. The devices, systems, and methods described in this paper address some of these drawbacks.

[0160] Figure 6An example of an intravascular guidewire is shown. "Side-emitting guidewire" is designated "A", "sensing volume" is designated "B", "clot" is designated "C", and "arbitrarily shaped tip" is designated "D". In this embodiment, optical wavelength radiation is emitted and received at a distance from the tip (e.g., at least 3 cm away from the tip). Therefore, the tip can be shaped, bent, or otherwise designed as needed without affecting spectral sensing. Optical wavelength radiation is emitted and received substantially perpendicularly to the main axis of the guidewire. The interventional physician can then "pass through the clot," but once this is done, a pullback can be performed and the clot composition scanned along the length of the guidewire without losing guidewire position. To obtain optimal signal, the interventional physician may have to twist (i.e., rotate) the guidewire to optimize the overlap between the sensing volume and the blood clot, and minimize the overlap between the sensing volume and the vessel wall and possibly other surrounding tissues. To help find the correct angle of rotation, the guidewire can include radiopaque markers indicating the sensing direction. Alternatively, when a spectrum corresponding to the blood vessel wall is detected, feedback can be provided to the operator in the form of a warning.

[0161] Figure 7 An example of an intravascular guidewire is shown. The arrows indicate directions toward the "optical radiation source" (A) and the "spectrometer" (B), located outside the intravascular portion of the guidewire at the other end of the optical fiber. "Hollow tube" is indicated by "C," "optical fiber" by "D," "emitted optical wavelength radiation" by "E," "hole with transparent filler" by "F," "slit with reflective coating" by "G," and "terminus" by "H." Typically, the guidewire comprises a hollow tube or coil with an optical fiber inside the lumen. The hole or gap in the tube at the distal end of the optical fiber allows optical wavelength radiation to exit and enter the lumen. The hole or gap is typically sealed with a transparent material to ensure optimal optical contact with the outside and to prevent blood ingress. The optical fiber is usually fixed only at its distal end to allow it to slide within the lumen for bending. Alternatively, the optical fiber can be placed in a groove along the side of the guidewire. The guidewire can be surrounded by an additional layer (e.g., a constriction tube). These surrounding layers will also be transparent to the wavelengths used for spectroscopy. Optical wavelength radiation is emitted from the optical fiber in a direction substantially perpendicular to the main axis of the guidewire (which is typically also the main axis of the optical fiber). Ideally, the same optical fiber will be used to collect optical wavelength radiation reflected from surrounding tissue and blood. To deflect the optical wavelength radiation approximately 90 degrees away from / into the optical fiber, the end of the fiber can be cut at an angle of approximately 45 degrees. Optionally, the cut edge of the optical fiber can be coated with a reflective coating. Alternatively, a separate mirror can be used. Optionally, the facets of the mirror or the optical fiber can be shaped to focus or defocus the optical wavelength radiation.

[0162] Figure 8 An example of an intravascular microcatheter and guidewire device is shown. "Transparent catheter" is designated "A", "lateral emission guidewire" is designated "B", "clot" is designated "C", and "arbitrarily shaped tip" is designated "D". In this embodiment, the guidewire is combined with a microcatheter that is transparent at its distal end for the wavelengths used in the spectroscopy. Once the microcatheter has passed the clot, the guidewire is inserted, and spectral measurements are taken through the wall of the microcatheter without the guidewire dislodging. Mechanical stops can be used to prevent the guidewire tip from dislodging from the microcatheter. The advantage of this arrangement is that the requirements for the guidewire (and guidewire operator) are lower than in embodiments without a transparent microcatheter because the guidewire itself never comes into contact with the clot or the vessel wall.

[0163] Figure 9 An example of an intravascular guidewire is shown. "Side-emitting guidewire" is designated "A", two "sensing volumes" are designated "B", a "clot" is designated "C", and an "arbitrarily shaped tip" is designated "D". In this embodiment, the neurointerventional physician does not need to rotate the guidewire. This is because, in this embodiment, the sensing volume covers a 360-degree loop around the guidewire. This ensures that the clot is always within the sensing volume of the guidewire. It should be noted that the sensing volume will also include the vessel wall and possibly surrounding tissue, resulting in a lower signal-to-noise ratio than embodiments that only inquire about blood clots. In this embodiment, the optical fiber is inside a hollow tube (i.e., not in a recess). Instead of a single hole / window, the tube has multiple openings or a single slit (with a window if desired). To deflect the optical wavelength radiation with a 360-degree radius, the tip of the optical fiber can have a tapered shape (e.g., Figure 10 (as shown), this can be achieved, for example, through polishing. In Figure 10 In this diagram, "optical radiation source" is represented by "A", "spectrometer" by "B", "hollow tube" by "C", "optical fiber" by "D", "emitted optical wavelength radiation" by "E", "hole or slit with transparent filler" by "F", "cone" by "G", and "terminus" by "H". If the refractive index and cone angle of the optical fiber are suitable, total internal reflection at the cone will deflect the optical wavelength radiation from the optical fiber into a laterally expanding annular shape away from the device within the pulse tube. Therefore, the sensed volume can be an "annular" volume, in which the optical wavelength radiation from this volume can be scattered / reflected back and collected.

[0164] Figure 11An example of a guidewire within a vascular bundle is shown. "Optical radiation source" is represented by "A", "spectrometer" by "B", "hollow tube" by "C", "optical fiber" by "D", "emitted optical wavelength radiation" by "E", "hole or slit with transparent filler" by "F", "reflective cone" by "G", and "terminus" by "H". In this embodiment, a conical mirror is positioned near the distal end of the optical fiber to generate a 360-degree loop of optical wavelength radiation around the guidewire (thus generating a ring or annular field of optical wavelength radiation). Ideally, the angle of the mirror cone is 45 degrees. Other, less efficient methods exist for shaping the optical wavelength radiation profile; for example, a scattering medium may be positioned in front of the optical fiber.

[0165] Figure 12 An example of an intravascular guidewire is shown. "Optical radiation source" is represented by "A", "spectrometer" by "B", "hollow tube" by "C", "fiber optic cable" by "D", "first sensing volume" by "E", "orifice with transparent filler" by "F", "wavelength selection element" by "G", "second sensing volume" by "H", and "terminus" by "I". While lateral sensing guidewires offer advantages over antegrade sensing guidewires in many situations as discussed above, there are also situations where antegrade sensing guidewires are advantageous. This is especially true if the physician does not want to pass through a clot. Therefore, it would be highly beneficial if a single guidewire could provide two sensing options simultaneously, or if the physician could switch between only two sensing options. Thus, measurements can be taken simultaneously at two locations because these areas can be probed with different wavelength ranges. However, it would be beneficial, for example, to limit exposure to optical wavelength radiation and provide practical switching. Therefore, switching can actually be achieved by simply changing the spectrum of optical wavelength radiation coupled to the fiber. Another way to provide two sensing options is to use two optical fibers in the guidewire, one for forward sensing and one for lateral sensing. However, this lateral and forward sensing can also be provided by a single optical fiber. Therefore, it is possible to have one lateral beam and one forward beam, or two or more lateral beams (which can form a ring emission) and forward emission, and they can operate in the same wavelength range or in different wavelength ranges.

[0166] Therefore, this system enables the interrogation of different sensing volumes by using different wavelengths or wavelength ranges for each sensing volume. For example, a wavelength range of approximately 450 nm to 900 nm (primarily visible optical radiation) can be used to distinguish between different types of blood clots in one sensing volume, and a wavelength range of approximately 1000–1600 nm (near-infrared (i.e., NIR) optical radiation) can be used to simultaneously distinguish between different types of blood clots in a second sensing volume. Alternatively, the same or similar wavelengths can be used, for example, wavelengths of 520 nm, 830 nm, 1270 nm, and 1450 nm can be used to distinguish between different types of blood clots in one sensing volume, while wavelengths of 525 nm, 835 nm, 1275 nm, and 1455 nm can be used to distinguish between different types of blood clots in a second sensing volume. Moreover, a wavelength selection element integrated into the guidewire can be used to ensure that the sensing volume E is irradiated with an optical wavelength having a different wavelength than that of the sensing volume H. Different types of wavelength selection elements can be used. For example, wavelength-selective elements (such as fiber Bragg gratings, i.e., FBGs) can be used to couple optical wavelengths within a predetermined wavelength range to the outside of the optical fiber. Figure 12 The image shows a depiction of this situation.

[0167] Figure 13 An example of an intravascular guidewire is shown. "Optical radiation source" is represented by "A", "spectrometer" by "B", "hollow tube" by "C", "optical fiber" by "D", "sensing volume 1 (visible optical radiation)" by "E", "visible transmission IR absorption window" by "F", "50:50 beam splitter / coupler" by "G", "sensing volume 2 (infrared optical radiation)" by "H", and "visible absorption IR transmission window" by "I". In this embodiment, approximately half of the optical wavelength radiation is coupled out at the first sensing volume regardless of wavelength, and then optical filters are used to filter out unwanted optical wavelength radiation. These optical filters can be integrated into the optical window or optical filler of the opening in the sealed hollow tube. A 50:50 beam splitter / coupler has been mentioned here; however, those skilled in the art will recognize that other ratios can also be used.

[0168] Therefore, in general, the above disclosure relates to an intravascular device having an associated optical wavelength radiation generation and spectral data generation system. The intravascular device may have one or more of the following features: i) at least one optical fiber designed to emit optical wavelength radiation into the interior of a blood vessel or adjacent biological tissue and collect a portion of the optical wavelength radiation reflected by the tissue; ii) a portion of the optical wavelength radiation emitted and received in a direction perpendicular to the main axis of the intravascular device; iii) a portion of the optical wavelength radiation emitted and received proximally from the tip of the intravascular device (significantly proximally from the tip can mean more than 3 cm away from the tip, and if the intravascular device includes a functional tip with a coil, the portion of the optical wavelength radiation emitted and received proximally from the length covered by the coil; the coil is a standard design element in medical guidewires to achieve desired mechanical properties, wherein the tip of the guidewire must generally be more flexible than the shaft; the coil is therefore used to provide the desired “softness”); iv) a tip that is for its mechanical properties rather than needle-like. Its optical or sensing properties are optimized, v) to emit and receive optical wavelength radiation from / to the distal end, which can involve using a wavelength-selective element to emit / receive different optical wavelengths at different sensing volumes, vi) to emit and receive optical wavelength radiation from / to the lateral direction, which can involve using a wavelength-selective element to emit / receive different optical wavelengths at different sensing volumes, vii) to emit and receive optical wavelength radiation from / to the lateral direction in a ring or annular shape, so that rotation or twisting of the guidewire is not required to provide rotational sensitivity, viii) an intravascular microcatheter that is optically transparent at a predetermined length from the distal end and has a lumen suitable for receiving the guidewire, so that the intravascular device can be measured from inside the catheter through the catheter wall, ix) a (non-transmissive) marker (or other feedback mechanism) that helps the intravascular device to twist to maximize the overlap between the blood clot and the spectral sensing volume.

[0169] Intravascular devices for determining blood clot composition in the peripheral vascular system are shared above. Figure 1 Many features are described. However, by comparison, including the aforementioned optical interaction element 40 or providing the aforementioned two beams is not necessary. (Reference) Figure 1 An intravascular device for determining the composition of blood clots in a peripheral vascular system may therefore include:

[0170] Slender member 20; and

[0171] Fiber optic cable 30;

[0172] In this embodiment, at least a portion of the elongated member 20 is configured to be inserted into a portion of the patient's vascular system;

[0173] Wherein, at least a portion of the optical fiber 30 is located within the elongated member 20;

[0174] The optical fiber is configured to transmit optical wavelength radiation;

[0175] The intravascular device is configured to emit a portion of the optical wavelength radiation from the elongated member so that it is partially scattered and / or reflected by the vascular system; and

[0176] The intravascular device is configured to collect at least some of the scattered and / or reflected optical wavelength radiation and couple the at least some of the scattered and / or reflected optical wavelength radiation into the optical fiber.

[0177] In the apparatus used to determine the composition of blood clots in the peripheral vascular system, optionally:

[0178] In one example, the optical wavelength radiation is generated by an optical radiation source that simultaneously emits broadband optical radiation.

[0179] In one example, the optical wavelength radiation is generated by an optical radiation source that emits narrowband optical radiation and scans the emitted optical wavelengths over a wavelength range to generate broadband optical radiation transmitted by optical fiber.

[0180] In another example, the intravascular device is a guidewire.

[0181] In another example, the intravascular device is a microcatheter.

[0182] In another example, the elongated member includes a non-transparent marking.

[0183] In another example, the elongated member is a tube.

[0184] In another example, the optical fiber includes a non-transmissive line marker.

[0185] In another example, the optical wavelength radiation can be axially emitted from the end wall of the elongated member, as shown in the reference. Figure 5 As shown in the illustration.

[0186] In another example, the optical wavelength radiation can be radially emitted from the elongated member, for example, in the form of a tapered emission profile, which can be provided by a beam redirector in the form of a region in the optical fiber exhibiting total internal reflection, or a beam redirector in the form of a mirror or beam splitter arranged laterally about the longitudinal axis of the optical fiber 30.

[0187] In another example, the optical wavelength radiation can be radially emitted from the elongated member in the form of a ring-shaped emission profile, for example by providing a reference for the optical fiber 30. Figure 10 The beam redirector shown is in the form of a distal tip with a conical shape, or, for example, by providing a reference... Figure 11 This is achieved by a beam redirector in the form of a described reflective cone.

[0188] In another example, the radial emission can be in a direction perpendicular to the longitudinal axis of the elongated member.

[0189] In another example, the radial emission may be provided at a position at least 3 cm from the end of the elongated member.

[0190] In another example, an endovascular device for determining the composition of blood clots in the peripheral vascular system can be incorporated into, as in reference [reference missing] Figure 2 In the microcatheter 110 shown, the optical fiber 30 may be provided with a beam redirector as described above to radially emit optical wavelength radiation from the elongated member. Figure 2 At least a portion of the microcatheter 110 is configured to be inserted into a portion of a patient's vascular system. The microcatheter includes at least one light-transmitting wall portion configured to emit optical wavelength radiation. The endovascular device is configured to slide within the microcatheter along its longitudinal axis. The microcatheter and the endovascular device are configured such that when the endovascular guidewire is positioned at one or more longitudinal locations along the longitudinal axis of the microcatheter, optical wavelength radiation is emitted from the microcatheter through the at least one light-transmitting wall portion, and scattered and / or reflected optical wavelength radiation enters the microcatheter through the at least one light-transmitting wall portion.

[0191] Now for reference Figure 3 This describes an intravascular research system 200 for determining the composition of blood clots in a peripheral vascular system. The system includes the intravascular device for determining the composition of blood clots in a peripheral vascular system as described above. The intravascular device for determining the composition of blood clots in a peripheral vascular system may optionally be included as referenced above. Figure 2The described microcatheter. A system 200 for determining the composition of blood clots in a peripheral vascular system further includes an optical radiation source 210, an optical radiation detector 220, and a processing unit 230. The optical radiation source is configured to generate optical wavelength radiation over a broadband range and couple the optical wavelength radiation into the optical fiber. The optical radiation detector is configured to generate at least one detection signal based on the scattered and / or reflected optical wavelength radiation. The processing unit is configured to determine at least one spectrally resolved dataset based on the at least one detection signal. The at least one spectrally resolved dataset includes a spectrum corresponding to collagen. The processing unit is configured to determine collagen content based on the spectrum corresponding to collagen and to determine information about the blood clot based on the collagen content.

[0192] As described in more detail below, the presence of collagen in peripheral vascular clots is a marker of late-stage clot differentiation and age. In these clots, fibroblasts have time to infiltrate the clot and begin the process of forming an endothelial layer covering the clot surface. In these chronic clots, t-PA and other thrombolytic agents may fail to penetrate the thrombus, depending on the degree of endothelialization. Therefore, blood clots with a high collagen content can resist thrombolysis. In fact, attempting thrombolysis on these types of clots can put patients at risk, as the clot may become mobile and cause acute injury downstream (e.g., in the form of a pulmonary embolism). Therefore, determining the collagen content of peripheral vascular clots in this way can inform medical practitioners and allow them to select the optimal treatment modality for each patient.

[0193] Blood clot differentiation

[0194] The following provides details on distinguishing between a first type of blood clot rich in red blood cells and a second type of blood clot rich in fibrin, which can include determining the amount of red blood cells present and / or the amount of fibrin present. In other words, the classification between "red blood cell rich clots" and "fibrin rich clots" takes into account that a true blood clot can exist between red blood cell rich clots and fibrin rich clots, and can exist as a blood clot that is half of one or the other.

[0195] As discussed above, the currently described system includes an intravascular device or microcatheter as part of an intravascular system for optically interrogating a patient. Broadband optical wavelength radiation spanning multiple optical wavelengths can be used in optical interrogation. Therefore, a true broadband light source can be used, for example. Broadband optical wavelength radiation can also be provided in the form of a tunable laser or in the form of multiple narrowband optical radiation sources (e.g., LEDs or lasers emitting narrowband optical radiation simultaneously or sequentially). Thus, in the example, the optical radiation source and detector can operate as a spectrally resolved unit, wherein the broadband optical wavelength radiation coupled to the optical fiber of the intravascular device involves a tunable laser operating over a wavelength range, and this optical wavelength radiation is scattered and / or reflected back from the patient and detected to provide a spectrally resolved dataset. In another example, a single-shot broadband optical wavelength radiation beam can be coupled into an optical fiber and collected and analyzed, for example, by a spectrometer to provide a spectrally resolved dataset.

[0196] The system described herein enables the determination of the classification of the actual form of blood clots. Distinguishing between a first and a second blood clot type can include determining at least one physiological parameter, wherein the at least one physiological parameter includes one or more of the following: the amount of hemoglobin; hemoglobin oxygen saturation; the amount of scattering; vascular encapsulation parameters; water content; and the amount of at least one hemoglobin derivative. For example, at least one physiological parameter can be determined by fitting an optical model derived from diffusion theory to the measured spectrum. In the example, fitting the spectrum to the optical model can include considering wavelength-dependent absorption coefficients and wavelength-dependent reduced scattering coefficients. In the example, a double power law can be used to describe the wavelength dependence of the reduced scattering, where the first power law corresponds to the contribution of Mie scattering and the second power law corresponds to the contribution of Rayleigh scattering. The wavenumber (i.e., cm⁻¹) is used to determine the scattering. -1 The decreasing scattering μ as a function of wavelength λ, expressed in units of λ. ′ s can be represented as:

[0197]

[0198] Where λ0 is a normalized wavelength that can be set to 800 nm in this example, and parameter a corresponds to the reduced scattering amplitude at this exemplary wavelength. The reduced scattering corresponds to the sum of Mie scattering and Rayleigh scattering, and ρ MR It is defined as the Mie / Rayleigh fraction of scattering. The decreasing scattering slope of Mie scattering is denoted by b and is related to the particle size.

[0199] Further details regarding the determination of physiological parameters can be found in the following two articles: “Estimation of lipid and water concentrations in scattering media with diffuse optical spectroscopy from 900 to 1600 nm” by R. Nachabé, BHWHendriks, AEDesjardins, M. van der Voort, MB van der Mark, and HJCMSterenborg (J. Biomed. Opt. 15, 2010) and “Estimation of biological chromophores using diffuse optical spectroscopy: benefit of extending the UVVIS wavelength range to include 1000 to 1600 nm” by Rami Nachabé, Benno HWHendriks, Marjolein van der Voort, Adrien E. Desjardins, and Henricus JCMSterenborg (Optics Express 18, 2010, p. 1432).

[0200] Determining at least one physiological parameter can include one or more of the following: fitting an optical model to at least one spectral-resolved dataset; applying at least one multivariate analysis tool to the at least one spectral-resolved dataset; performing partial least squares discriminant analysis on the at least one spectral-resolved dataset; applying a support vector machine to the at least one spectral-resolved dataset; applying k-nearest neighbor analysis; and applying a deep learning algorithm to the at least one spectral-resolved dataset. The at least one multivariate analysis tool includes principal component analysis (PCA). Distinguishing between a first blood clot type and a second blood clot type can include using a lookup table.

[0201] In the aforementioned intravascular study system 200 for determining the composition of blood clots in the peripheral vascular system, similar optical analysis techniques can be used to determine collagen content. In system 200, a spectral-resolved dataset is generated. The spectral-resolved dataset includes spectra corresponding to collagen. The processing unit is configured to determine collagen content based on the spectra corresponding to collagen, and to determine information about the blood clot based on the collagen content.

[0202] In peripheral vascular disease, it has been found that the collagen content of clots can be used to differentiate between recently formed (i.e., acute) blood clots and older (i.e., chronic) blood clots. This is because collagen content increases with clot age. Clot age is a useful factor for medical practitioners to determine which of a variety of treatment options is best suited for the clot (e.g., whether to perform thrombectomy or thrombolysis, and therefore which of a variety of treatment devices to use). In one exemplary embodiment, collagen content can be determined by fitting the aforementioned optical model to the measured spectrum, as shown in Equation 4 and Equation 5 in the article by Nachabé et al. in 2011. Figure 2 As described in diffuse reflectance spectroscopy, collagen exhibits absorption bands in the wavelength range of 400–1700 nm, which is particularly suitable for use with readily available optical components. Particularly useful characterization of collagen absorption bands appear at approximately 950 nm ± 50 nm, 1030 nm ± 50 nm, 1230 nm ± 50 nm, and 1500 nm ± 100 nm.

[0203] To demonstrate that diffuse reflectance spectroscopy can be used to accurately determine collagen content, various blood clot “simulated” samples were prepared from collagen and fibrin, and the spectra of these samples were measured using a spectrophotometer. The collagen in the simulated samples represented collagen found in blood clots, and fibrin was added as a pairing to the blood clot simulated samples to represent fibrin, which is also typically present in real blood clots. It was also demonstrated that collagen can be measured in the presence of relatively similar spectral signatures to fibrin.

[0204] In response, Figure 14 The figure illustrates the relationship between changes in light intensity (in arbitrary units) measured for three simulated blood clot samples and wavelength in nanometers. Figure 14 The uppermost curve shows the spectrum of a pure collagen sample (100% collagen). Figure 14 The lowest curve shows the spectrum of a pure fibrin sample (100% fibrin). The middle curve shows a mixture of 50% collagen and 50% fibrin. Figure 14 As can be seen, the characteristic absorption bands of collagen appear at approximately 950+ / -50nm, 1030nm+ / -50nm, 1230nm+ / -50nm, and 1500nm+ / -100nm.

[0205] Then use the above for Figure 14The spectra were also used to determine a collagen content "predictor" by using optical models of the spectra of simulated samples with collagen fractions of 25% and 75%, and this collagen content "predictor" was compared with the actual collagen fraction, such as... Figure 15 As shown. Figure 15 The diagram illustrates the relationship between the predictive power (predictor factor) of simulated blood clots for several measurements and the collagen fraction (%) (i.e., the real-world case). Ideally, Figure 15 The value of the predictor parameter in the parameter will be equal to Figure 15 The collagen fraction in it. From Figure 15 It can be seen that the model accuracy increases with the increase of collagen fraction.

[0206] Various alternative optical arrangements are also suitable for measuring collagen content, including Raman spectroscopy, a molecularly specific technique with unique spectral characteristics that can be used to detect collagen.

[0207] A corresponding method for determining the collagen content of peripheral vascular clots using the aforementioned intravascular study system 200 for determining the composition of blood clots in the peripheral vascular system may include the following steps:

[0208] The optical radiation source is used to generate optical wavelength radiation over a wide bandwidth.

[0209] Broadband optical wavelength radiation is coupled into the optical fiber of the intravascular device or the intravascular microcatheter and guidewire device;

[0210] The intravascular device or the intravascular microcatheter and guidewire device is used to collect scattered and / or reflected optical wavelength radiation from the patient's vascular structures;

[0211] The optical wavelength radiation detector generates at least one detection signal based on the scattered and / or reflected optical wavelength radiation;

[0212] The processing unit determines at least one spectral-resolved dataset based on the at least one detection signal, the at least one spectral-resolved dataset including spectra corresponding to collagen; and

[0213] The processing unit determines the collagen content based on the spectrum corresponding to collagen, and determines information about blood clots based on the collagen content.

[0214] In another exemplary embodiment, a computer program or computer program unit is provided, characterized in that the computer program or computer program unit is configured to perform method steps of a method according to an embodiment of the foregoing embodiments on a suitable system.

[0215] Therefore, the computer program unit can be stored in the computer unit, and the computer program unit can also be part of the embodiment. The computing unit can be configured to perform the steps of the above-described method or to cause the execution of the steps of the above-described method. Furthermore, the computing unit can be configured to operate components of the above-described apparatus and / or system. The computing unit can be configured to automatically operate and / or execute user commands. The computer program can be loaded into the working memory of the data processor. Therefore, the data processor can be equipped to execute the method according to one embodiment of the foregoing embodiments. The computer program or output unit can be integrated into an imaging or navigation system.

[0216] This exemplary embodiment of the invention covers both computer programs that use the invention from the outset and computer programs that use the invention by means of updating existing programs.

[0217] In addition, the computer program unit may be able to provide all the necessary steps to complete the process of the exemplary embodiments of the method described above.

[0218] According to another exemplary embodiment of the present invention, a computer-readable medium, such as a CD-ROM, a USB stick, etc., is provided, wherein the computer-readable medium has computer program units stored on the computer-readable medium, the computer program units being described in the preceding sections.

[0219] Computer programs can be stored and / or distributed on suitable media, such as optical storage media or solid-state media supplied together with or as part of other hardware, but can also be distributed in other forms, such as via the Internet or other wired or wireless telecommunications systems.

[0220] However, computer programs can also exist on networks (such as the World Wide Web) and can be downloaded from such networks into the working memory of a data processor. According to another exemplary embodiment of the invention, a medium is provided for making computer program units available for download, said computer program units being arranged to perform a method according to an embodiment of the previously described embodiments of the invention.

[0221] It should be noted that embodiments of the present invention are described with reference to different subjects. In particular, some embodiments are described with reference to method claims, while others are described with reference to apparatus claims. However, unless otherwise stated, those skilled in the art will infer from the above and below that any combination of features relating to different subjects, in addition to any combination of features belonging to one type of subject matter, is also considered to be disclosed in this application. However, all features can be combined to provide synergistic effects beyond the simple addition of features.

[0222] Although the invention has been illustrated and described in detail in the accompanying drawings and the foregoing description, such illustrations and descriptions should be considered illustrative or exemplary, and not restrictive. The invention is not limited to the disclosed embodiments. Those skilled in the art, through studying the drawings, the disclosure, and the claims, will understand and implement other variations of the disclosed embodiments in practicing the claimed invention.

[0223] In the claims, the word "comprising" does not exclude other elements or steps, and the words "a" or "an" do not exclude a plurality. A single processor or other unit can perform the functions of several items recited in the claims. Although certain measures are recited in different dependent claims, this does not indicate that combinations of these measures cannot be advantageously used. No reference numerals in the claims should be construed as limiting the scope.

Claims

1. An intravascular device (10), comprising: Slender member (20); Single optical fiber (30); as well as At least one optical interaction element (40); At least a portion of the elongated member (20) is configured to be inserted into a portion of the patient's vascular system; Wherein, at least a portion of the single optical fiber (30) is located within the elongated member (20); The single optical fiber is configured to transmit optical wavelength radiation; The intravascular device is configured to emit portions of the optical wavelength radiation from the elongated member with at least two radiation beams so as to be partially scattered and / or reflected by the vascular system, wherein the emission of the at least two radiation beams includes the interaction of the transmitted optical wavelength radiation with the at least one optical interaction element. The at least two radiating beams include a first radiating beam emitted from the sidewall of the elongated member and originating from the single optical fiber, wherein the first radiating beam forms an annular emission profile substantially perpendicular to the longitudinal axis of the elongated member, so as to be partially scattered and / or reflected by the vascular system; and The intravascular device is configured to: collect at least some of the scattered and / or reflected optical wavelength radiation, and couple the at least some of the scattered and / or reflected optical wavelength radiation into the single optical fiber, including the utilization of the at least one optical interaction element.

2. The apparatus of claim 1, wherein, The at least two radiation beams include a second radiation beam emitted from the sidewall of the elongated member.

3. The apparatus of claim 2, wherein, The wavelength range of the first radiated beam is different from that of the second radiated beam.

4. The apparatus of any one of claims 2-3, wherein, The first radiating beam is emitted from the elongated member at a first longitudinal position, and the second radiating beam is emitted from the elongated member at a second longitudinal position different from the first longitudinal position.

5. The apparatus of any one of claims 1-3, wherein, The at least two radiation beams include radiation beams emitted from the end wall of the elongated member.

6. The apparatus of claim 5, wherein, The wavelength range of the first radiated beam is different from the wavelength range of the radiated beam emitted from the end wall of the elongated member.

7. The apparatus of any of claims 2-3, wherein, The at least two radiation beams include radiation beams emitted from the end wall of the elongated member, and the wavelength range of the first radiation beam is different from the wavelength range of the radiation beam emitted from the end wall of the elongated member, and the wavelength range of the second radiation beam is different from the wavelength range of the radiation beam emitted from the end wall of the elongated member.

8. The apparatus of any of claims 1-3 and 6, wherein, The at least one optical interaction element includes a wavelength selection element.

9. The apparatus of any of claims 1-3 and 6, wherein, A portion of the single optical fiber at its distal end is fixedly connected to the elongated member; and wherein at least a portion of the single optical fiber located within the elongated member, other than the fixed distal end, is not fixedly connected to the elongated member.

10. An intravascular device (10), comprising: Slender member (20); Single optical fiber (30); as well as At least one optical interaction element (40); In this embodiment, at least a portion of the elongated member is configured to be inserted into a portion of the patient's vascular system; Wherein, at least a portion of the single optical fiber is located within the elongated member; The single optical fiber is configured to transmit optical wavelength radiation; The intravascular device is configured to emit at least a portion of the optical wavelength radiation from the single optical fiber out of the elongated member as a radiating beam, the radiating beam forming an annular emission profile substantially perpendicular to the longitudinal axis of the elongated member so as to be partially scattered and / or reflected by the vascular system, wherein the emission of the radiating beam includes the interaction of the transmitted optical wavelength radiation with the at least one optical interaction element; and The intravascular device is configured to: collect at least some of the scattered and / or reflected optical wavelength radiation, and couple the at least some of the scattered and / or reflected optical wavelength radiation into the single optical fiber, including the utilization of the at least one optical interaction element.

11. An intravascular microcatheter and guidewire device (100), comprising: Microcatheter (110); as well as The intravascular device (10) according to any one of claims 1-9 or the intravascular device (100) according to claim 10. In this embodiment, at least a portion of the microcatheter is configured to be inserted into a portion of the patient's vascular system; The microcatheter includes at least one light-transmitting wall portion; The intravascular device is configured to slide within the microcatheter along its longitudinal axis; and The microcatheter and the intravascular device are configured such that when the intravascular guidewire is positioned at one or more longitudinal locations along the longitudinal axis of the microcatheter, optical wavelength radiation is emitted from the microcatheter through at least one light-transmitting wall portion of the microcatheter, and scattered and / or reflected optical wavelength radiation enters the microcatheter through at least one light-transmitting wall portion of the microcatheter.

12. An intravascular study system (200), comprising: The intravascular device (10) according to any one of claims 1-9, or the intravascular device (10) according to claim 10, or the intravascular microcatheter and guidewire device (100) according to claim 11. Optical radiation source (210); Optical radiation detector (220); and Processing unit (230); The optical radiation source is configured to generate optical wavelength radiation over a broadband range and to couple the optical wavelength radiation into the single optical fiber. The optical radiation detector is configured to generate at least one detection signal based on the scattered and / or reflected optical wavelength radiation. The processing unit is configured to determine at least one spectral-resolved dataset based on the at least one detection signal; and The processing unit is configured to determine information about blood clots based on the at least one spectral resolution dataset.

13. A method of conducting an intravascular study using the intravascular study system (200) of claim 12, wherein, The method includes: The optical radiation source is used to generate optical wavelength radiation over a wide bandwidth. Broadband optical wavelength radiation is coupled into a single optical fiber of the intravascular device or the intravascular microcatheter and guidewire device; The intravascular device or the intravascular microcatheter and guidewire device is used to collect scattered and / or reflected optical wavelength radiation from the patient's vascular structures; The optical wavelength radiation detector generates at least one detection signal based on the scattered and / or reflected optical wavelength radiation; The processing unit determines at least one spectral-resolved dataset based on the at least one detection signal; and The processing unit determines information about the blood clot based on the at least one spectral resolution dataset.

14. A system (200) for determining the composition of a peripheral venous clot, comprising: An intravascular device for determining the composition of blood clots in a peripheral vascular system, the intravascular device comprising: Slender member (20); as well as Single optical fiber (30); In this embodiment, at least a portion of the elongated member is configured to be inserted into a portion of the patient's vascular system; Wherein, at least a portion of the single optical fiber is located within the elongated member; The single optical fiber is configured to transmit optical wavelength radiation; The intravascular device is configured to emit a portion of the optical wavelength radiated from the single optical fiber out of the elongated member with a radiating beam, the radiating beam forming an annular emission profile substantially perpendicular to the longitudinal axis of the elongated member so as to be partially scattered and / or reflected by the vascular system. The intravascular device is configured to: collect at least some of the scattered and / or reflected optical wavelength radiation, and couple the at least some of the scattered and / or reflected optical wavelength radiation into the single optical fiber; and the system further includes: Optical radiation source (210); Optical radiation detector (220); and Processing unit (230); The optical radiation source is configured to generate optical wavelength radiation over a broadband range and to couple the optical wavelength radiation into the single optical fiber. The optical radiation detector is configured to generate at least one detection signal based on the scattered and / or reflected optical wavelength radiation. The processing unit is configured to determine at least one spectral resolution dataset based on the at least one detection signal; Wherein, the at least one spectral resolution dataset includes spectra corresponding to collagen; and The processing unit is configured to: determine the collagen content based on the spectrum corresponding to collagen, and determine information about blood clots based on the collagen content.

15. A method for determining the collagen content of a peripheral vascular clot using the system for determining the composition of a peripheral venous clot according to claim 14, said system for determining the composition of a blood clot in the peripheral vascular system, the method comprising the steps of: The optical radiation source is used to generate optical wavelength radiation over a wide bandwidth. Broadband optical wavelength radiation is coupled into a single optical fiber of the intravascular device or the intravascular microcatheter and guidewire device; The intravascular device or the intravascular microcatheter and guidewire device is used to collect scattered and / or reflected optical wavelength radiation from the patient's vascular structures; The optical wavelength radiation detector generates at least one detection signal based on the scattered and / or reflected optical wavelength radiation; The processing unit determines at least one spectral resolution dataset based on the at least one detection signal, the at least one spectral resolution dataset including a spectrum corresponding to collagen; and The processing unit determines the collagen content based on the spectrum corresponding to collagen, and determines information about blood clots based on the collagen content.

16. A computer program product for controlling a system according to claim 12, wherein when executed by a processor, the computer program product is configured to perform the method according to claim 13.

17. A computer program product for controlling a system according to claim 14, wherein when executed by a processor, the computer program product is configured to perform the method according to claim 15.

18. A computer-readable medium having stored thereon a computer program product according to claim 16 or 17.

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