Tags

Type your tag names separated by a space and hit enter

Collateral damage to the ureter and Nitinol stone baskets during thulium fiber laser lithotripsy.
Lasers Surg Med 2015; 47(5):403-10LS

Abstract

BACKGROUND

The experimental Thulium fiber laser (TFL) is currently being studied as a potential alternative lithotripter to the clinical gold standard Holmium:YAG laser. Safety studies characterizing undesirable Holmium:YAG laser-induced damage to ureter tissue and stone baskets have been previously reported. Similarly, this study characterizes TFL induced ureter and stone basket damage.

METHODS

A TFL beam with energy of 35 mJ per pulse, pulse duration of 500 µs, and variable pulse rates of 50-500 Hz, was delivered through 100-µm-core optical fibers, to either porcine ureter wall, in vitro, or a standard 1.9-Fr Nitinol stone basket wire. Ureter perforation times were measured and gross, histological, and optical coherence tomography images of the ablation area were acquired. Stone basket damage was graded as a function of pulse rate, number of pulses, and working distance.

RESULTS

TFL operation at 150, 300, and 500 Hz produced mean ureter perforation times of 7.9, 3.8, and 1.8 seconds, respectively. Collateral damage widths averaged 510, 370, and 310 µm. Nitinol wire damage decreased with working distance and was non-existent at distances greater than 1.0 mm. In contact mode, 500 pulses delivered at pulse rates ≥300 Hz (≤1.5 seconds) were sufficient to cut Nitinol wires.

CONCLUSIONS

The TFL, operated in low pulse energy and high pulse rate mode, may provide a greater safety margin than the standard Holmium:YAG laser for lithotripsy, as evidenced by longer TFL ureter perforation times and shorter non-contact working distances for stone basket damage than previously reported with Holmium:YAG laser.

Authors+Show Affiliations

Department of Physics and Optical Science, University of North Carolina at Charlotte, Charlotte, North Carolina.Department of Physics and Optical Science, University of North Carolina at Charlotte, Charlotte, North Carolina.McKay Department of Urology, Carolinas Medical Center, Charlotte, North Carolina.Department of Physics and Optical Science, University of North Carolina at Charlotte, Charlotte, North Carolina. McKay Department of Urology, Carolinas Medical Center, Charlotte, North Carolina. Department of Urology, Johns Hopkins Medical Institutions, Baltimore, Maryland.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

25872759

Citation

Wilson, Christopher R., et al. "Collateral Damage to the Ureter and Nitinol Stone Baskets During Thulium Fiber Laser Lithotripsy." Lasers in Surgery and Medicine, vol. 47, no. 5, 2015, pp. 403-10.
Wilson CR, Hardy LA, Irby PB, et al. Collateral damage to the ureter and Nitinol stone baskets during thulium fiber laser lithotripsy. Lasers Surg Med. 2015;47(5):403-10.
Wilson, C. R., Hardy, L. A., Irby, P. B., & Fried, N. M. (2015). Collateral damage to the ureter and Nitinol stone baskets during thulium fiber laser lithotripsy. Lasers in Surgery and Medicine, 47(5), pp. 403-10. doi:10.1002/lsm.22348.
Wilson CR, et al. Collateral Damage to the Ureter and Nitinol Stone Baskets During Thulium Fiber Laser Lithotripsy. Lasers Surg Med. 2015;47(5):403-10. PubMed PMID: 25872759.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Collateral damage to the ureter and Nitinol stone baskets during thulium fiber laser lithotripsy. AU - Wilson,Christopher R, AU - Hardy,Luke A, AU - Irby,Pierce B, AU - Fried,Nathaniel M, Y1 - 2015/04/14/ PY - 2015/01/27/accepted PY - 2015/4/16/entrez PY - 2015/4/16/pubmed PY - 2016/4/5/medline KW - ablation KW - basket KW - holmium KW - kidney KW - laser KW - lithotripsy KW - stones KW - thulium KW - ureter SP - 403 EP - 10 JF - Lasers in surgery and medicine JO - Lasers Surg Med VL - 47 IS - 5 N2 - BACKGROUND: The experimental Thulium fiber laser (TFL) is currently being studied as a potential alternative lithotripter to the clinical gold standard Holmium:YAG laser. Safety studies characterizing undesirable Holmium:YAG laser-induced damage to ureter tissue and stone baskets have been previously reported. Similarly, this study characterizes TFL induced ureter and stone basket damage. METHODS: A TFL beam with energy of 35 mJ per pulse, pulse duration of 500 µs, and variable pulse rates of 50-500 Hz, was delivered through 100-µm-core optical fibers, to either porcine ureter wall, in vitro, or a standard 1.9-Fr Nitinol stone basket wire. Ureter perforation times were measured and gross, histological, and optical coherence tomography images of the ablation area were acquired. Stone basket damage was graded as a function of pulse rate, number of pulses, and working distance. RESULTS: TFL operation at 150, 300, and 500 Hz produced mean ureter perforation times of 7.9, 3.8, and 1.8 seconds, respectively. Collateral damage widths averaged 510, 370, and 310 µm. Nitinol wire damage decreased with working distance and was non-existent at distances greater than 1.0 mm. In contact mode, 500 pulses delivered at pulse rates ≥300 Hz (≤1.5 seconds) were sufficient to cut Nitinol wires. CONCLUSIONS: The TFL, operated in low pulse energy and high pulse rate mode, may provide a greater safety margin than the standard Holmium:YAG laser for lithotripsy, as evidenced by longer TFL ureter perforation times and shorter non-contact working distances for stone basket damage than previously reported with Holmium:YAG laser. SN - 1096-9101 UR - https://www.unboundmedicine.com/medline/citation/25872759/Collateral_damage_to_the_ureter_and_Nitinol_stone_baskets_during_thulium_fiber_laser_lithotripsy_ L2 - https://doi.org/10.1002/lsm.22348 DB - PRIME DP - Unbound Medicine ER -