A catheter system (100) for treating a treatment site (106) within or adjacent to a vessel wall (108) or a heart valve includes an inflatable balloon (104), an optical fiber (122), and an energy source (124). The optical fiber (122) has a fiber proximal end (122P), and a fiber distal end (122D) positioned within the inflatable balloon (104). The optical fiber (122) is configured to receive an energy pulse so that the optical fiber (122) emits light energy in a direction away from the optical fiber (122) to generate a plasma pulse within the inflatable balloon (104). The optical fiber (122) can be tapered from the fiber proximal end (122P) toward the fiber distal end (122D). The energy source (124) in optical communication with the fiber proximal end (122P) of the optical fiber (122), and can include a laser. The optical fiber (122) includes a first fiber member (250) and a second fiber member (258) that is coupled to the first fiber member (250). The first fiber member (250) can be fused to the second fiber member (258) in a fused region (256). The first fiber member (250) and the second fiber member (258) can be formed as a unitary structure. The catheter system (100) can also include a ferrule (248) that encircles the fused region (256).

A method for treating a treatment site (106) within or adjacent to a vessel wall (108) or heart valve includes tapering an optical fiber (122) from a fiber proximal end (122P) to a fiber distal end (122D); positioning the optical fiber (122) such that the fiber distal end (122D) is positioned within an inflatable balloon (104); coupling an energy source (124) in optical communication with the fiber proximal end (122P); and receiving an energy pulse from the energy source (124) into the fiber proximal end (122P) so that the optical fiber (122) emits light energy in a direction away from the optical fiber (122) to generate a plasma pulse within the inflatable balloon (104). The method can further include coupling a first fiber member (250) to a second fiber member (258), which can include fusing the first fiber member (250) to the second fiber member (258) at a fused region (256); and encircling the fused region (256) with a ferrule (248).

A tapered fiber optoacoustic emitter includes a nanosecond laser configured to emit laser pulses and an optic fiber. The optic fiber includes a tip configured to guide the laser pulses. The tip has a coating including a diffusion layer and a thermal expansion layer, wherein the diffusion layer includes epoxy and zinc oxide nanoparticles configured to diffuse the light while restricting localized heating. The thermal expansion layer includes carbon nanotubes (CNTs) and Polydimethylsiloxane (PDMS) configured to convert the laser pulses to generate ultrasound. The frequency of the ultrasound is tuned with a thickness of the diffusion layer and a CNT concentration of the expansion layer.

A medical interventional tool has distal and proximal ends. A responsive material is located at the distal end or elsewhere along the interventional tool and is capable of providing a temperature-dependent or pressure-dependent optical response. At least one optical guide is in optical communication with the responsive material to collect an optical signal from the responsive material located at the distal end or other location along the interventional tool. The at least one optical guide further guides the collected optical signal to an optical output at the proximal end of the interventional tool. An optical response analyzer is configured to receive the collected optical signal from the optical output and to process the collected optical signal to derive therefrom a temperature or pressure reading or indication representative of a temperature or pressure at the distal end or other location along the interventional tool.

A peripheral light-emitting linear light guide member is composed of an optical fiber including a core having an outer periphery surface exposed from a cladding at one end in a longitudinal direction, and a light-scattering member covering an entire periphery of the outer periphery surface at an exposed portion of the core over a predetermined axial length range. The light-scattering member scatters a light emitted from the outer periphery surface of the core. In the light-scattering member, light-scattering particles are dispersion-mixed with an optically transparent base material having a higher refractive index than a refractive index of the core. An amount of the light-scattering particles around an outer periphery of the core is higher at a distal end of the light-scattering member than at an end closer to the cladding.

The present disclosure is related to field of Fiber Feedback (FFB) technology, and provides a method and system for estimating the distance between a fiber end and a target. The method includes illuminating, by a Light Emitting, Transmitting and Detecting (LETD) system, the target with laser light of different wavelengths having low and high water absorption coefficients, using different laser light sources, as well as receiving a returned signal corresponding to the incident laser light of different wavelengths, and detecting the returned signal to measure intensity values of the returned signal of a specific wavelength. Using the measured intensity values, a processing unit may estimate distance between the fiber end and the target. The present disclosure enables accurate estimation of distance between a fiber end and the target. The present disclosure also provides a robust distance estimation technique which is compatible with different types of targets.

A surgical laser system includes an array of laser diodes that are configured to output laser energy, a fiber bundle, a delivery fiber, and a tubular sheath. The fiber bundle includes a plurality of optical fibers and has a proximal end that is configured to receive laser energy from the array of laser diodes. The delivery fiber includes a proximal end that is configured to receive laser energy from a distal end of the fiber bundle. The tubular sheath defines a lumen, in which at least a portion of the delivery fiber is disposed. The tubular sheath is insertable into a working channel of an endoscope or a cystoscope. A distal end of the tubular sheath is configured to deliver laser energy discharged from the delivery fiber into a body of a patient.

Described herein are systems with interleaved light sources and methods of their use. In some embodiments, a system includes a plurality of light sources, each of which has a bright phase and a dark phase, the system being arranged and constructed so that, for a first light source and a second light source of the plurality, the bright phase of the first light source occurs during the dark phase of a second light source. The example method may further include providing light from the second light source during a dark phase of the first light source. A first and/or second light source may be a swept source or a broadband source. A first and/or second light source may be a laser.

A plastic optical fiber is excellent in translucency, heat resistance, resistance to environment and the like, and has highly excellent flexibility. The plastic optical fiber contains a core and at least one layer of cladding, wherein the bending elastic modulus of the innermost layer of the cladding is 20 to 70 MPa, the glass transition temperature of the innermost layer of the cladding is 10° C. or lower, and the storage elastic modulus of the innermost layer of the cladding at 30° C. is 1×10.sup.6 Pa to 4×10.sup.7 Pa.

An Optical fiber with modified distal end and related methods are provided. The optical fiber extends from a proximal end portion to a distal end portion and includes a core, a cladding, a coating, and an optional jacket. The distal end portion comprises a portion with an enlarged outer diameter.