Molding of laser energy by shaped optic fiber tips

✍ Scribed by Dr. Helen Ward

• Publisher: John Wiley and Sons
• Year: 1987
• Tongue: English
• Weight: 751 KB
• Volume: 7
• Category: Article
• ISSN: 0196-8092
• DOI: 10.1002/lsm.1900070506

✦ Synopsis

The development of a new technique for laser recannalizing atheromatous vessels has inherent problems concerning heat damage to the vessel walls. A theoretical analysis of 2,100 light rays in large bulb end (output end) fibers compared to a standard flat end fiber showed (1) a much higher-intensity focus; (2) a 125.4% increase in number of output rays (with respect to number of input rays) in the convergent output beam, due to multiple reflectionshefractions ("stars" and "triangles") and standing waves, in the large bulb end, compared to 48.6% in the flat end; (3) 83.69% energy in the converging beam of the large bulb end, compared to 46.1 % energy in the flat end; and (4) a rapidly divergent beam after focus.

Hence, theoretically a wide area of plaque could be burnt off more rapidly with less heat conduction into the vessel walls.

Coupling efficiency was experimentally shown to be greatly increased by also having a bulb at the optic fiber input end.