High-powered holmium-laser ablation: comparison of setting effectiveness using tissue-surrogate model.
OBJECTIVE
The 100-W holmium laser, in conjunction with a sidefiring 550-microm fiber, can ablate prostate glands as large as 40 g to relieve lower urinary-tract symptoms. We evaluated the effect of various setting combinations on ablation efficiency using beef kidney as a tissue-surrogate model.


METHODS
Beef kidney specimens (mean weight 44.8 +/- 3.1 g) were secured in a cylinder, which was submerged in a water-filled tank through which a 27F resectoscope and 550-microm sidefiring fiber were positioned. Four energy/frequency combinations were tested, with each used to treat 10 kidney specimens. The difference between the mean pretreatment and post-treatment weights of each treatment group were compared statistically with Student's t-test.


RESULTS
The largest mean weight difference after treatment (8.94 +/- 2.38 g) was achieved using 3.2 J and 25 Hz. This mass reduction was significantly greater than that of all other combinations except 2.5 J and 40 Hz.


CONCLUSIONS
Use of the 3.2 J and 25 Hz setting combination resulted in the greatest amount of ablation in this tissue-surrogate model, suggesting that maximal energy settings may provide an advantage in tissue vaporization using the 100-W holmium laser. Clinical assessment must be performed to substantiate these findings.
Kuo
Ramsay L
RL
Department of Urology, Thomas Jefferson University, Jefferson Medical College, Philadelphia, Pennsylvania 19107, USA. ramsay.kuo@jefferson.edu
Paterson
Ryan F
RF
Siqueira
Tibério M
TM
Kim
Samuel C
SC
Lingeman
James E
JE
D000818:Animals; D002417:Cattle; D006695:Holmium; D007668:Kidney / Q000033:anatomy & histology* / Q000601:surgery*; D053685:Laser Therapy / Q000379:methods*; D023421:Models, Animal; D009929:Organ Size
D006695:Holmium