Abstract: Methods and apparatus for creating fluid flow from one location to another are disclosed. The fluid flow is created via the absorption of repetitive pulses of radiation in a fluid to generate bubbles that expand and collapse repetitively. This fluid mechanism, or pumping phenomenon, can be used to aid removal of a total or partial occlusion in a body passage by disrupting a surface of the occlusion with acoustic shock and pressure waves and/or by causing mechanical disruption of the occlusive material. Appropriate selection of materials and particular constructions improve apparatus flexibility.

Abstract: The invention encompasses methods and apparatus for pumping fluid from one location to another through the repetitive expansion and collapse of bubbles generated as a result of the absorption of repetitive pulses of radiation in a fluid. This pumping phenomenon can be used to aid removal of a total or partial occlusion in a body passage by emulsifying the occlusion with acoustic shock and pressure waves or by causing mechanically disrupting the occlusive material.

Abstract: The invention encompasses methods and flexible apparatus for delivering radiation energy to a radiation-absorbing fluid within the apparatus to generate a series of expanding and collapsing bubbles therein, and thereby generate flow in a fluid surrounding the apparatus. Effective fluid flow is obtained via at least one optical fiber, disposed within the apparatus near a distal opening therein, that, when fired, tends to pump fluid with respect to the apparatus, and at least one other optical fiber, disposed within the apparatus in the vicinity of a side opening thereof, that, when fired, tends to agitate fluid near its distal end. These pumping and agitative actions cause a net fluid motion that is particularly effective in disrupting a partial or total occlusion in a body passage, such as a blood vessel, within which the apparatus is operated.

Abstract: Partial or total occlusions of fluid passages within the human body are removed by positioning an array of optical fibers in the passage and directing treatment radiation pulses along the fibers, one at a time, to generate a shock wave and hydrodynamics flows that strike and emulsify the occlusions. A preferred application is the removal of blood clots (thrombin and embolic) from small cerebral vessels to reverse the effects of an ischemic stroke. The operating parameters and techniques are chosen to minimize the amount of heating of the fragile cerebral vessel walls occurring during this photo acoustic treatment. One such technique is the optical monitoring of the existence of hydrodynamics flow generating vapor bubbles when they are expected to occur and stopping the heat generating pulses propagated along an optical fiber that is not generating such bubbles.

Abstract: An apparatus, including a light detecting means, determines the actual position of an optical fiber array having one or more, but fewer than all, short fibers by detecting light transmitted through the short fiber(s) as a laser beam is horizontally and/or vertically scanned across the proximal fiber end(s). The fiber array is attached to an alignment block that facilitates delivery of the array to an accurate positioning means comprising two substantially parallel dowels.

Abstract: Apparatus for pumping fluid from one location to another via generation of bubbles in fluid, and expansion and callapse thereof, are described. These apparatus deliver repetitive pulses of radiation to a fluid to form bubbles therein. The expansion and collapse of the bubbles cause fluid motion or pumping. This pumping can be used to facilitate removal of a total or partial occlusion in a body passage by a variety of mechanisms. The apparatus are flexible to facilitate use within a body passage.

Abstract: The invention encompasses methods and apparatus for pumping fluid from one location to another through the repetitive expansion and collapse of bubbles generated as a result of the absorption of repetitive pulses of radiation in a fluid. This pumping phenomenon can be used to aid removal of a total or partial occlusion in a body passage by emulsifying the occlusion with acoustic shock and pressure waves or by mechanically disrupting the occlusive material.