Canine Transurethral Laser-Induced Prostatectomy

Assimos, Dean G.; McCullough, David L.; Woodruff, Ralph D.; Harrison, Lloyd H.; Hart, Lawrence E.; Li, Weijia

doi:10.1089/end.1991.5.145

Cited by 35 publications

(13 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nevertheless, these studies have proved the feasibility of safe laser prostatectomy. A follow-up report by Assimos et al (1991) confirmed that the Tulip system caused significant tissue ablation in the canine prostate.…”

Section: Discussionmentioning

confidence: 88%

Laser Ablation of the Prostate in Patients with Benign Prostatic Hypertrophy

Costello

Bowsher

Bolton

et al. 1992

British Journal of Urology

307

107

View full text Add to dashboard Cite

Seventeen patients with bladder neck obstruction due to benign prostatic hypertrophy have been treated with the Neodymium: YAG laser. We review our experience since the first patient was treated in September 1990. Using a prototype deflecting gold alloy tip on a quartz laser fibre (Lateralase TM), we ablated obstructing prostatic adenoma and constricting bladder neck tissue. Experience with this technique has enabled a patient population to be defined in whom laser therapy for prostatic obstruction may be effective. The treatment is relatively simple, speedy and attended by virtually no blood loss. Laser ablation therapy may offer some advantages over conventional transurethral resection of the prostate (TURP) in a selected subgroup of patients. The advent of new delivery systems may make laser ablation therapy a practical alternative to TURP.

show abstract

Section: Discussionmentioning

confidence: 88%

Laser Ablation of the Prostate in Patients with Benign Prostatic Hypertrophy

Costello

Bowsher

Bolton

et al. 1992

British Journal of Urology

307

107

View full text Add to dashboard Cite

show abstract

“…In recent years, meaningful attempts have been made to develop laser technology appropriate for the performance of simple or subtotal prostatectomy in the hope that lasers will produce a much lower morbidity profile compared to standard surgical techniques. The first of these purpose-designed laser devices for prostatectomy was the TULIP (Intra-Sonix), an ultrasound-guided system using a Neodymium:YAG laser source to cause coagulation necrosis in the prostate [3,4]. Investigators have shown reasonable efficacy and minimal morbidity associated with this approach 151.…”

Section: Introductionmentioning

confidence: 99%

Dosimetry studies utilizing the urolase right-angle firing Neodymium: YAG laser fiber in the human prostate

et al. 1996

View full text Add to dashboard Cite

Background and Objective Until recently, little or no objective data have been available to support either the choice of power setting or the timing of laser applications to achieve optimal tissue ablation in the human prostate. The objective of this study was to define quantitative dosimetry curves for the Urolase right angle laser fiber in human prostates. Study Design/Materials and Methods Transurethral Neodymium: YAG laser application was performed with the Urolase right‐angle laser fiber in adult human prostates prior to planned radical surgery. Depth and volume of prostatic tissue coagulation for single, continuous laser applications were measured at variable power settings from 20 to 60 watts while holding total energy delivery constant. Then, holding the power setting constant at 40 watts, the extent of tissue coagulation was measured for variable treatment times from 60 to 120 seconds. Results Peak tissue coagulation was observed at 40 watts up to a maximum of 14 mm tissue penetration and 4.23 cc volume coagulated following a single spot laser application. The mean depth of tissue coagulation at 40 watts power setting was 13.5 mm, with a mean volume of tissue coagulation of 3.68 cc. The mean depth of tissue penetration at 40 watts was more than 25% greater than that observed at 60 watts, and the mean volume of tissue coagulation was 190% greater than that observed at 60 watts. As treatment time was increased from 60 to 90 seconds, extent of tissue coagulation increased significantly. However, beyond 90 seconds continuous laser application at 40 watts, a plateau in tissue effects was observed, with minimal increase in tissue coagulation between 90 and 120 seconds. Histologic examination of prostates removed acutely showed heat‐induced damage to both stromal and glandular epithelial elements in laser‐treated areas. At 1 year, the prostatic urethra was lined with a normal transitional epithelium, and mild periurethral fibrosis with focal squamous metaplasia was seen. Conclusion: Using the Urolase right‐angle laser fiber, this study suggests that 40 watts power setting and 90 seconds continuous application time with a Neodymium: YAG laser source represent optimal treatment parameters to maximize prostatic tissue coagulation. © 1996 Wiley‐Liss, Inc.

show abstract

“…Since, further experimental animal reports and dosimetry stud ies have subsequently been published [13,14,16,17], Up to now, the first data of clinical trials show very promising results [28][29][30][31], yet there has been too little investigating as to VLAP's impact and expansion in human prostate. We find it rather astonishing, all the more so because the laser procedure depends on numerous parameters which are not yet conclusively evident.…”

Section: Discussionmentioning

confidence: 99%

“…Johnson, Costello and Kabalin were, however, the first to form the basis for visual laser ablation. These authors, who have repeatedly published about the impact and results of this procedure performed since 1991 in a number of experiments in animals [13][14][15][16][17], delineated that a burn of 3,600 J as a total aimed at the tissue in ques tion produces the maximal necrotic zone.…”

Section: Visual Laser Ablation O F the Prostatementioning

confidence: 99%

MRI-Correlated Morphological Changes after Nd:YAG Laser Treatment of the Human Prostate with the SideFocus® Fiber

Sulser

Jochum²,

Böni³

et al. 1997

Urol Int

View full text Add to dashboard Cite

Optimal treatment parameters and appropriate methods of examination for Nd:YAG laser coagulation of the human prostate in dependence of power-setting and time using the SideFocus® side-firing delivery system have been determined. Transurethral free-beam laser coagulation was performed in 10 patients prior to planned radical prostatectomy or cystoprostatectomy. Thereof, 6 patients underwent transperitoneal laparoscopic lymphadenectomy and laser coagulation of the prostate between 4 and 9 days prior to open surgery. These same patients had undergone MRI examination with an endorectal coil during staging and prior to radical prostatectomy. Depth and volume of coagulated prostatic tissue of a 4-quadrant laser application were measured at power-settings of 40 W/90 s and 60 W/60 s. There was no difference in volume coagulation between the two treatment modalities. In contrast there was a significant difference in volume coagulation between those prostates removed at 4–9 days and those removed at 60–210 min after laser coagulation. In histological and MRI examination, however, there was a strong correlation with view to coagulation volume in histological and MRI examination. Using the SideFocus® side-firing laser fiber, both treatment modalities showed comparable volume coagulation. Laser-induced changes are conclusively discernible by 4 days, MRI examination with an endorectal coil thus being perfectly suitable for assessment.

show abstract

Canine Transurethral Laser-Induced Prostatectomy

Cited by 35 publications

References 6 publications

Laser Ablation of the Prostate in Patients with Benign Prostatic Hypertrophy

Laser Ablation of the Prostate in Patients with Benign Prostatic Hypertrophy

Dosimetry studies utilizing the urolase right-angle firing Neodymium: YAG laser fiber in the human prostate

MRI-Correlated Morphological Changes after Nd:YAG Laser Treatment of the Human Prostate with the SideFocus® Fiber

Contact Info

Product

Resources

About