Optical fiber pressure sensor
In an example, an apparatus includes an elongated assembly, at least a portion of which is sized, shaped, or otherwise configured to be inserted into a human body to measure a physiological parameter at an internal location within the body. The elongated assembly can include an elongated member. The elongated assembly can include an optical fiber pressure sensor, located at a distal portion of the elongated member. The elongated assembly can include a housing disposed about the optical fiber pressure sensor. The elongated assembly can include a guidewire tube, coupled to the housing, the guidewire tube defining a receptacle sized and shaped to accept a guidewire to permit the distal portion of the elongated member to slide along the guidewire during insertion of the elongated assembly into the human body.
1. An apparatus comprising:
an elongated assembly, at least a portion of which is sized, shaped, or otherwise configured to be inserted into a human body to measure a physiological parameter at an internal location within the body, wherein the elongated assembly includes:
an elongated member having a length, wherein the elongated member defines a longitudinal optical fiber carrier that extends longitudinally along at least a first portion of the length of the elongated member, wherein the optical fiber carrier includes at least one of a groove or a flat;
an optical fiber, helically extending longitudinally along the optical fiber carrier, the optical fiber configured to communicate light between a location outside of the human body and a portion of the optical fiber that is to be located at or near the internal location within the human body at which the physiological parameter is to be measured, wherein the optical fiber carrier is sized for and carries only one optical fiber, and wherein the only one optical fiber has a diameter of between 25 micrometers and 30 micrometers, inclusive;
an optical fiber pressure sensor, located at a distal portion of the elongated member, the optical fiber pressure sensor including:
a first optical fiber anchor, to which a first portion of the optical fiber is secured;
a second optical fiber anchor, to which a second portion of the optical fiber is secured;
a gasket longitudinally arranged between the first and second anchors and including a passage through which a third portion of the optical fiber passes, the gasket being more elastic or compliant than the first and second anchors; and
wherein the first and second anchors and the gasket are arranged to use the elastic or compliant nature of the gasket to allow at least one of longitudinal stretching or compression of the optical fiber between the first and second anchors to sense pressure at the internal location within the body;
a housing disposed about the optical fiber pressure sensor; and
a guidewire tube, coupled to the housing, the guidewire tube defining a receptacle sized and shaped to accept a guidewire to permit the distal portion of the elongated member to slide along the guidewire during insertion of the elongated assembly into the human body.
2. The apparatus of claim 1 , wherein the optical fiber includes a Fiber Bragg Grating (FBG) located at the optical fiber pressure sensor.
3. The apparatus of claim 2 , wherein the optical fiber pressure sensor includes an FBG interferometer, included in the optical fiber, wherein the FBG interferometer comprises at least two Fiber Bragg Gratings, wherein the at least two Fiber Bragg Gratings are arranged or otherwise configured to permit optically discriminating, at or near the internal location within the body at which pressure is to be measured, between a change in pressure and a change in temperature.
4. The apparatus of claim 1 , wherein the optical fiber carrier includes a first guidewire, and further including a second guidewire, sized and shaped to pass through the guidewire tube, wherein the guidewire tube is attached to the first guidewire.
5. The apparatus of claim 1 , wherein the optical fiber is a first optical fiber, the apparatus comprising a proximal end connector configured to be coupled to a proximal end of the elongated member, the proximal end connector comprising:
a distal portion including:
a tube defining an interior first passage that is sized and shaped to receive the proximal end of the elongated member;
a distal guide ferrule, at least a portion of which defines a transitional interior second passage that is sized and shaped to allow the optical fiber to be transitionally routed from an outer circumferential periphery of the proximal end of the elongated member to a more longitudinally central location toward a proximal end of the distal guide ferrule; and
a proximal portion including:
a proximal guide ferrule including a lumen sized and shaped for passing a second optical fiber having a larger diameter than the first optical fiber; and
wherein the distal and proximal portions are user-attachable to bring the first and second optical fibers into concentric longitudinal alignment with each other.
6. A method comprising:
inserting a first guidewire into a human body toward an internal location within the body at which it is desired to measure a physiological parameter;
inserting into the human body an elongated assembly, at least a portion of which is sized, shaped, or otherwise configured to be inserted into a human body to measure a physiological parameter at an internal location within the body, wherein the elongated assembly includes:
an elongated member having a length, wherein the elongated member defines a longitudinal optical fiber carrier that extends longitudinally along at least a first portion of the length of the elongated member, wherein the optical fiber carrier includes at least one of a groove or a flat;
an optical fiber, helically extending longitudinally along the optical fiber carrier, the optical fiber configured to communicate light between a location outside of the human body and a portion of the optical fiber that is to be located at or near the internal location within the human body at which the physiological parameter is to be measured, wherein the optical fiber carrier is sized for and carries only one optical fiber, and wherein the only one optical fiber has a diameter of between 25 micrometers and 30 micrometers, inclusive;
an optical fiber pressure sensor, located at a distal portion of the elongated member, the optical fiber pressure sensor including:
a first optical fiber anchor, to which a first portion of the optical fiber is secured;
a second optical fiber anchor, to which a second portion of the optical fiber is secured;
a gasket longitudinally arranged between the first and second anchors and including a passage through which a third portion of the optical fiber passes, the gasket being more elastic or compliant than the first and second anchors; and
wherein the first and second anchors and the gasket are arranged to use the elastic or compliant nature of the gasket to allow at least one of longitudinal stretching or compression of the optical fiber between the first and second anchors to sense pressure at the internal location within the body;
a housing disposed about the optical fiber pressure sensor; and
a guidewire tube, coupled to the housing, the guidewire tube defining a receptacle sized and shaped to accept a guidewire to permit the distal portion of the elongated member to slide along the guidewire during insertion of the elongated assembly into the human body; and
wherein the inserting into the human body the elongated assembly includes guiding the elongated assembly using the first guidewire passing through the guidewire tube.
7. An apparatus comprising:
an elongated assembly, at least a portion of which is sized, shaped, or otherwise configured to be inserted into a human body to measure a physiological parameter at an internal location within the body, wherein the elongated assembly includes:
an elongated member having a length, wherein the elongated member defines a longitudinal optical fiber carrier that extends longitudinally along at least a first portion of the length of the elongated member, wherein the optical fiber carrier includes at least one of a groove or a flat;
a first optical fiber, helically extending longitudinally along the optical fiber carrier, the optical fiber configured to communicate light between a location outside of the human body and a portion of the optical fiber that is to be located at or near the internal location within the human body at which the physiological parameter is to be measured, wherein the optical fiber carrier is sized for and carries only one optical fiber, and wherein the only one optical fiber has a diameter of between 25 micrometers and 30 micrometers, inclusive;
an optical fiber pressure sensor, located at a distal portion of the elongated member;
a housing disposed about the optical fiber pressure sensor;
a guidewire tube, coupled to the housing, the guidewire tube defining a receptacle sized and shaped to accept a guidewire to permit the distal portion of the elongated member to slide along the guidewire during insertion of the elongated assembly into the human body; and
a proximal end connector configured to be coupled to a proximal end of the elongated member, the proximal end connector comprising:
a distal portion including:
a tube defining an interior first passage that is sized and shaped to receive the proximal end of the elongated member;
a distal guide ferrule, at least a portion of which defines a transitional interior second passage that is sized and shaped to allow the optical fiber to be transitionally routed from an outer circumferential periphery of the proximal end of the elongated member to a more longitudinally central location toward a proximal end of the distal guide ferrule; and
a proximal portion including:
a proximal guide ferrule including a lumen sized and shaped for passing a second optical fiber having a larger diameter than the first optical fiber;
wherein the distal and proximal portions are user-attachable to bring the first and second optical fibers into concentric longitudinal alignment with each other.