Intravascular lithotripsy
A medical device may include an elongated body having a distal elongated body portion and a central longitudinal axis. The medical device may include a balloon positioned along the distal elongated body portion. The balloon may be configured to receive a fluid to inflate the balloon such that an exterior balloon surface contacts a calcified lesion within a patient's vasculature. The medical device may include one or more pressure wave emitters positioned along the central longitudinal axis of the elongated body. The one or more pressure wave emitters may be configured to propagate at least one pressure wave through the fluid to fragment the calcified lesion. At least one pressure wave emitter may include an optical fiber configured to transmit laser energy into the balloon. The laser energy may be configured to create a cavitation bubble in the fluid.
1 . A device, comprising:
an optical fiber configured to pass laser energy therethrough, the optical fiber having an emitting location configured to transmit laser energy into a fluid causing a cavitation bubble to propagate a pressure wave;
an elongated body having a proximal portion and a distal portion opposite the proximal portion, the elongated body extending along a central longitudinal axis, the optical fiber extending at least partially along the elongated body and spaced from the central longitudinal axis; and
a controller configured to translate the optical fiber longitudinally independently from the elongated body, the optical fiber extending at least partially through the controller and therefrom towards the elongated body, the controller comprising:
a lower telescope fixedly coupled to at least a portion of the optical fiber;
an upper telescope telescopically coupled to the lower telescope, such that the lower telescope is configured to translate longitudinally within and from the upper telescope;
a longitudinal actuator configured to translate the lower telescope with respect to the upper telescope, thereby translating the optical fiber longitudinally;
a proximal stopping feature associated with a proximal treatment location;
a distal stopping feature associated with a distal treatment location; and
at least one stopping feature located between the proximal stopping feature and the distal stopping feature,
wherein the proximal stopping feature, the distal stopping feature, and the at least one stopping feature are configured to i) prevent longitudinal movement of the lower telescope in at least one direction, ii) provide a resistance for longitudinal movement of the lower telescope in at least one direction, or iii) both, and
wherein the stopping features are located along the path on which the longitudinal actuator moves.
2 . The device of claim 1 , wherein the lower telescope defines a fiber lumen therethrough, wherein the optical fiber is disposed within the fiber lumen.
3 . The device of claim 1 , wherein the lower telescope, the upper telescope, or both, comprise stainless steel.
4 . The device of claim 1 , further comprising a slack feature configured to manage slack of the optical fiber as it is longitudinally translated.
5 . The device of claim 4 , wherein the slack feature comprises a pin.
6 . The device of claim 1 , further comprising a proximal support fixedly coupled to the lower telescope, the proximal support configured to provide structural support to each of the lower telescope and the optical fiber.
7 . The device of claim 6 , wherein the proximal support is configured to encapsulate at least a portion of the lower telescope.
8 . The device of claim 1 , further comprising a seal configured to prevent fluid flow to the upper telescope.
9 . The device of claim 8 , wherein the seal includes a perforation sized for longitudinal movement therethrough by the lower telescope.
10 . The device of claim 1 , wherein the longitudinal actuator comprises a slider.
11 . The device of claim 1 , wherein the longitudinal actuator is configured to be translated a distance that is proportional to a distance translated by the lower telescope.
12 . The device of claim 11 , wherein the proportional distance translated by the lower telescope relative to the longitudinal actuator is based on a gear ratio, the longitudinal actuator comprising or coupled to one or more gears that are coupled to the lower telescope, wherein the gear ratio is defined by the one or more gears.
13 . The device of claim 1 , wherein each of the proximal stopping feature, the distal stopping feature, and the at least one stopping feature located between the proximal stopping feature and the distal stopping feature correspond to a predetermined position of the emitting location along the elongated body.
14 . The device of claim 1 , wherein an increased force on the longitudinal actuator overcomes the resistance of a respective stopping feature, thereby allowing further longitudinal translation of the lower telescope and optical fiber.
15 . The device of claim 1 , further comprising one or more numeric indicators, each corresponding to a predetermined position of the emitting location about the elongated body.
16 . The device of claim 15 , wherein the controller comprises the one or more numeric indicators.
17 . The device of claim 1 , wherein the at least one stopping feature is configured to provide tactile feedback indicative of a longitudinal position of the emitting location.
18 . The device of claim 1 , further comprising a distal hub configured to align the optical fiber about the elongated body.
19 . The device of claim 1 , further comprising a light emitting diode (LED) configured to backlight the longitudinal actuator.
20 . The device of claim 1 , further comprising a gear, wherein the longitudinal actuator comprises a rack for interacting with the gear in order to provide a gear ratio between longitudinal movement of the longitudinal actuator and longitudinal movement of the lower telescope.