Share Email Print

Proceedings Paper

Mid-infrared pulsed laser lithotripsy using an Er:YAG laser and a difference frequency generation laser
Author(s): Hisanao Hazama; Shinya Yamada; Katsunori Ishii; Kunio Awazu
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We conducted fundamental research on a novel lithotripsy technique using mid-infrared pulsed lasers. We irradiated gallstones extracted from the common bile duct using two mid-infrared lasers, namely, a difference-frequency generation (DFG) laser tunable within a wavelength range of 5.5-10 μm and an Er:YAG laser with a 2.94 μm wavelength, and then examined the depth and dimension of the crater formed. Some of the gallstones were continuously wet with distilled water during laser irradiation. The absorption spectrum of the gallstones was measured using a Fourier transform infrared spectrometer. The gallstones showed a strong peak around the wavelengths of 2.94 and 6.83 μm. In the case of DFG laser irradiation, the wavelength used was 6.83 μm and the average power density range of the laser was about 2-52 W/cm2. After irradiation, a relatively small hole with a depth range of 0.1-0.2 mm and a dimension within 0.01-0.04 mm2 was created. On the other hand, in the case of Er:YAG laser irradiation, the average power density range was about 0.20-0.78 kW/cm2. As the result, a large hole was made and the mass of 0.4-1.6 mg was removed. In conclusion, wet gallstones were more decomposed than dry gallstones in both cases of laser irradiation, and these techniques proved to be effective for gallstone lithotripsy.

Paper Details

Date Published: 2 May 2008
PDF: 9 pages
Proc. SPIE 6991, Biophotonics: Photonic Solutions for Better Health Care, 69911H (2 May 2008); doi: 10.1117/12.780636
Show Author Affiliations
Hisanao Hazama, Osaka Univ. (Japan)
Shinya Yamada, Osaka Univ. (Japan)
Katsunori Ishii, Osaka Univ. (Japan)
Kunio Awazu, Osaka Univ. (Japan)

Published in SPIE Proceedings Vol. 6991:
Biophotonics: Photonic Solutions for Better Health Care
Jürgen Popp; Wolfgang Drexler; Valery V. Tuchin; Dennis L. Matthews, Editor(s)

© SPIE. Terms of Use
Back to Top