0 308

Cited 34 times in

Optimization of the Erbium : YAG Laser for Precise Ineision of Ureteral and Urethral Tissues : In Vitro and In Vivo Results

Authors
 Nathaniel M. Fried  ;  Zelalem Tesfaye  ;  Pooya Hejazi  ;  Koon H. Rha  ;  Albert M. Ong 
Citation
 LASERS IN SURGERY AND MEDICINE, Vol.33(2) : 108-114, 2003 
Journal Title
 LASERS IN SURGERY AND MEDICINE 
ISSN
 0196-8092 
Issue Date
2003
MeSH
stricture ; urethra ; ureter ; Erbium ; Holmium ; laser ; ablation ; incision
Keywords
stricture ; urethra ; ureter ; Erbium ; Holmium ; laser ; ablation ; incision
Abstract
BACKGROUND AND OBJECTIVES: Tissue damage during endoscopic treatment of urethral and ureteral strictures may result in stricture recurrence. The Erbium:YAG laser ablates soft tissues with minimal peripheral damage and may be a promising alternative to cold knife and Holmium:YAG laser for precise incision of urological strictures. STUDY DESIGN/MATERIALS AND METHODS: Optimization of the Er:YAG laser was conducted using ex vivo porcine ureteral and canine urethral tissues. Preliminary in vivo studies were also performed in a laparoscopic porcine ureteral model with exposed ureter. Laser radiation with a wavelength of 2.94 microm, pulse lengths of 8, 70, and 220 microseconds, output energies of 2-35 mJ, fluences of 1-25 J/cm2, and pulse repetition rates of 5-30 Hz, was delivered through 250-microm and 425-microm core germanium oxide optical fibers in direct contact with tissue. RESULTS: Ex vivo perforation thresholds measured 2-4 J/cm2, with ablation rates of 50 microm/pulse at fluences of 6-11 J/cm2. In vivo perforation thresholds were approximately 1.8 J/cm2, with the ureter perforated in less than 20 pulses at fluences greater than 3.6 J/cm2. Peripheral thermal damage in tissue decreased from 30 to 60 microm to 10-20 microm as the laser pulse length decreased from 220 to 8 microseconds. Mechanical tissue damage was observed at the 8 microseconds pulse duration. CONCLUSIONS: The Er:YAG laser, operating at a pulse duration of approximately 70 microseconds, a fluence greater than approximately 4 J/cm2, and a repetition rate less than 20 Hz, is capable of rapidly incising urethral and ureteral tissues with minimal thermal and mechanical side-effects.
Full Text
http://onlinelibrary.wiley.com/doi/10.1002/lsm.10205/abstract
DOI
10.1002/lsm.10205
Appears in Collections:
1. College of Medicine (의과대학) > Dept. of Urology (비뇨의학교실) > 1. Journal Papers
Yonsei Authors
Rha, Koon Ho(나군호) ORCID logo https://orcid.org/0000-0001-8588-7584
URI
https://ir.ymlib.yonsei.ac.kr/handle/22282913/113427
사서에게 알리기
  feedback

qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Browse

Links