Fluid Catheter

Schematic representation of the fluid-core catheter used to deliver microsecond laser pulses to the clot during laser thrombolysis. The laser energy is launched from the laser into an optical fiber contained in a catheter. The fiber in turn launches the light into an optically clear liquid that transmits the light to the target by total internal reflection. The distal tip of the catheter is open-ended so that the fluid can flow out of the catheter and wash away the blood in front of the clot. A clear path for direct laser delivery to the clot is thus established. Another important advantage of the catheter over a bare solid fiber is that the fiber does not extend all the way to the end but ends roughly 20cm from the distal open end. The distal part of the catheter is therefore softer and more flexible and therefore less traumatic. Finally, the fluid is optically clear but radio-opaque that makes live monitoring by angiography possible.