EDITORIAL COMMENT
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REFERENCES 1. Kollmorgen, T. A., Malek, R. S. and Barrett, D. M.: Laser pros- tatectomy: two and a half years’ experience with aggressive multifocal therapy. Urology, 48: 217, 1996 2. Cowles, R. S., Kabalin, J. N., Childs, S. et al: A prospective randomized comparison of transurethral resection to visual laser ablation of the prostate for the treatment of benign prostatic hyperplasia. Urology, 46: 155, 1995 3. Kuntzman, R. S., Malek, R. S., Barrett, D. M. et al: High-power (60-watt) potassium-titanyl-phosphate laser vaporization prostatectomy in living canines and in human and canine cadavers. Urology, 49: 703, 1997 4. Kuntzman, R. S., Malek, R. S., Barrett, D. M. et al: Potassium- titanyl-phosphate laser vaporization of the prostate: a compar- ative functional and pathologic study in canines. Urology, 48: 575, 1996 5. Malek, R. S., Barrett, D. M. and Kuntzman, R. S.: High-power potassium-titanyl-phosphate (KTP/532) laser vaporization prostatectomy: 24 hours later. Urology, 51: 254, 1998 6. Stein, B. S.: Neodymium:yttrium-aluminum-garnet laser pros- tatectomy. Mayo Clin Proc, 73: 787, 1998 7. Kabalin, J. N., Bite, G. and Doll, S.: Neodymium:YAG laser coagulation prostatectomy: 3 years of experience with 227 patients. J Urol, 155: 181, 1996 8. Bruskewitz, R., Issa, M. M., Roehrborn, C. G. et al: A prospec- tive, randomized 1-year clinical trial comparing transurethral needle ablation to transurethral resection of the prostate for the treatment of symptomatic benign prostatic hyperplasia. J Urol, 159: 1588, 1998 9. Francisca, E. A. E., d’Ancona, F. C. H., Meuleman, E. J. H. et al: Sexual function following high energy microwave thermother- apy: results of a randomized controlled study comparing trans- urethral microwave thermotherapy to transurethral prostatic resection. J Urol, 161: 486, 1999 10. Gilling, P. J., Mackey, M., Cresswell, M. et al: Holmium laser versus transurethral resection of the prostate: a randomized prospective trial with 1-year followup. J Urol, 162: 1640, 1999 EDITORIAL COMMENTS Laser prostatectomies of all types have been advanced as an al- ternative to standard transurethral resection of the prostate for reasons of economy, efficacy and supposedly decreased sexual dys- function. In reality, long-term results have been less than over- whelming. In the KTP laser prostatectomy series originally reported a laser calibrated to 38 W. was used but in reality rarely delivered more than 20 W. of power. The procedure of vaporization was lengthy, tedious and often erratically performed. The authors detail a major breakthrough with a KTP laser that delivers 60 W. to a side firing fiber. Depth of penetration is improved producing a decreased operative lasering time. The obliteration of adenoma was possible to the limits of the prostatic capsule. Catheter time and postoperative symptoms scores compared favorably to re- cent transurethral resection series. These results can be duplicated by other investigators. The KTP 60 W. laser prostatectomy may be honestly compared favorably to transurethral resection of the pros- tate in all respects. Terrence R. Malloy Malloy-Carpiniello Associates Philadelphia, Pennsylvania The results of laser prostatectomy are directly dependent on a number of factors, including wavelength, power, duration and tech- nique. Some of the tissue characteristics that have made prostatec- tomy with a neodymium:YAG laser appealing, that is the excellent coagulation and hemostasis, also limit the cutting effect and ability to achieve immediate tissue removal. The holmium:YAG wavelength is absorbed more strongly by water and incises tissue better but is less hemostatic. The more tissue vaporization and cutting effect are achieved, the less tissue coagulation and hemostasis occur. The KTP laser used by the authors has characteristics of tissue absorption somewhat intermediate between a neodymium:YAG and holmium:YAG laser. The 532 nm. wavelength is strongly absorbed by hemoglobin but less so by water. The characteristics are some- what similar to an argon laser. The high power prototype KTP laser they used was able to achieve tissue vaporization which provided good immediate voiding outcomes. If the goal of prostatectomy is to remove or eradicate obstructive tissue, multiple laser wavelength and techniques can accomplish this goal. Virtually all have been reported as “patient and user- friendly.” It becomes difficult to make direct comparisons based upon small phase II studies. However, techniques that provide immediate tissue vaporization, such as the one described by the authors, appear to result in better outcomes than those that rely on tissue resorption and sloughing. Joseph A. Smith, Jr. Department of Urologic Surgery Vanderbilt University Medical Center Nashville, Tennessee POTASSIUM-TITANYL-PHOSPHATE LASER PROSTATECTOMY 1733
Transcript of EDITORIAL COMMENT
REFERENCES
1. Kollmorgen, T. A., Malek, R. S. and Barrett, D. M.: Laser pros-tatectomy: two and a half years’ experience with aggressivemultifocal therapy. Urology, 48: 217, 1996
2. Cowles, R. S., Kabalin, J. N., Childs, S. et al: A prospectiverandomized comparison of transurethral resection to visuallaser ablation of the prostate for the treatment of benignprostatic hyperplasia. Urology, 46: 155, 1995
3. Kuntzman, R. S., Malek, R. S., Barrett, D. M. et al: High-power(60-watt) potassium-titanyl-phosphate laser vaporizationprostatectomy in living canines and in human and caninecadavers. Urology, 49: 703, 1997
4. Kuntzman, R. S., Malek, R. S., Barrett, D. M. et al: Potassium-titanyl-phosphate laser vaporization of the prostate: a compar-ative functional and pathologic study in canines. Urology, 48:575, 1996
5. Malek, R. S., Barrett, D. M. and Kuntzman, R. S.: High-powerpotassium-titanyl-phosphate (KTP/532) laser vaporizationprostatectomy: 24 hours later. Urology, 51: 254, 1998
6. Stein, B. S.: Neodymium:yttrium-aluminum-garnet laser pros-tatectomy. Mayo Clin Proc, 73: 787, 1998
7. Kabalin, J. N., Bite, G. and Doll, S.: Neodymium:YAG lasercoagulation prostatectomy: 3 years of experience with 227patients. J Urol, 155: 181, 1996
8. Bruskewitz, R., Issa, M. M., Roehrborn, C. G. et al: A prospec-tive, randomized 1-year clinical trial comparing transurethralneedle ablation to transurethral resection of the prostate forthe treatment of symptomatic benign prostatic hyperplasia.J Urol, 159: 1588, 1998
9. Francisca, E. A. E., d’Ancona, F. C. H., Meuleman, E. J. H. et al:Sexual function following high energy microwave thermother-apy: results of a randomized controlled study comparing trans-urethral microwave thermotherapy to transurethral prostaticresection. J Urol, 161: 486, 1999
10. Gilling, P. J., Mackey, M., Cresswell, M. et al: Holmium laserversus transurethral resection of the prostate: a randomizedprospective trial with 1-year followup. J Urol, 162: 1640, 1999
EDITORIAL COMMENTS
Laser prostatectomies of all types have been advanced as an al-ternative to standard transurethral resection of the prostate forreasons of economy, efficacy and supposedly decreased sexual dys-function. In reality, long-term results have been less than over-whelming. In the KTP laser prostatectomy series originally reporteda laser calibrated to 38 W. was used but in reality rarely delivered
more than 20 W. of power. The procedure of vaporization waslengthy, tedious and often erratically performed.
The authors detail a major breakthrough with a KTP laser thatdelivers 60 W. to a side firing fiber. Depth of penetration is improvedproducing a decreased operative lasering time. The obliteration ofadenoma was possible to the limits of the prostatic capsule. Cathetertime and postoperative symptoms scores compared favorably to re-cent transurethral resection series. These results can be duplicatedby other investigators. The KTP 60 W. laser prostatectomy may behonestly compared favorably to transurethral resection of the pros-tate in all respects.
Terrence R. MalloyMalloy-Carpiniello AssociatesPhiladelphia, Pennsylvania
The results of laser prostatectomy are directly dependent on anumber of factors, including wavelength, power, duration and tech-nique. Some of the tissue characteristics that have made prostatec-tomy with a neodymium:YAG laser appealing, that is the excellentcoagulation and hemostasis, also limit the cutting effect and abilityto achieve immediate tissue removal. The holmium:YAG wavelengthis absorbed more strongly by water and incises tissue better but isless hemostatic. The more tissue vaporization and cutting effect areachieved, the less tissue coagulation and hemostasis occur.
The KTP laser used by the authors has characteristics of tissueabsorption somewhat intermediate between a neodymium:YAG andholmium:YAG laser. The 532 nm. wavelength is strongly absorbedby hemoglobin but less so by water. The characteristics are some-what similar to an argon laser. The high power prototype KTP laserthey used was able to achieve tissue vaporization which providedgood immediate voiding outcomes.
If the goal of prostatectomy is to remove or eradicate obstructivetissue, multiple laser wavelength and techniques can accomplishthis goal. Virtually all have been reported as “patient and user-friendly.” It becomes difficult to make direct comparisons based uponsmall phase II studies. However, techniques that provide immediatetissue vaporization, such as the one described by the authors, appearto result in better outcomes than those that rely on tissue resorptionand sloughing.
Joseph A. Smith, Jr.Department of Urologic SurgeryVanderbilt University Medical CenterNashville, Tennessee
POTASSIUM-TITANYL-PHOSPHATE LASER PROSTATECTOMY 1733
