Reduced OR, laser time observed with newer PVP system

Milan, Italy-The new-generation GreenLight XPS-180W laser system (American Medical Systems, Minnetonka, MN) achieved an improved rate of tissue vaporization and overall efficacy in patients with BPH compared to an earlier generation laser, according to results of a recent multicenter study.

The GreenLight XPS-180W uses an increased power setting and a new, larger-diameter MoXy fiber delivery system.

“Using the new GreenLight XPS-180W laser system, we experienced a 30% reduction in laser time and a 50% reduction in operative time, regardless of prostate size,” said first author Pierre-Alain Hueber, MD, PhD, urology resident at the University of Montreal Hospital Center, Montreal, who worked on the study with Kevin C. Zorn, MD, and colleagues.

“Not surprisingly, however, the energy usage increased according to prostate size. For prostates smaller than 80 cc, the energy expenditure was roughly 200 kJ, and around 400 kJ for prostates with volumes exceeding 80 cc. There was no significant difference between the two systems, however, in terms of energy usage.”

The study, which was presented at the European Association of Urology annual congress in Milan, Italy and at the AUA annual meeting in San Diego, included 1,809 patients who underwent GreenLight laser photoselective vaporization of the prostate (PVP) for the treatment of BPH from July 2007 to March 2012 at seven international centers. Of these, 1,187 cases (mean age, 71.54 years; mean prostate volume, 76.66 cc) were performed using the former generation HPS-120W laser system and 622 cases (average age, 68.93 years; mean prostate volume, 70.1 cc) using the new XPS-180W system.

Operative parameters such as total operating room time, laser time, total energy usage, and fiber number were collected prospectively.

Significantly increased efficacy

The investigation revealed that the XPS-180W system significantly reduced both the operative and laser times, with similar total energy delivery per given prostate volume, suggesting a significantly increased efficacy compared to the HPS-120W system, according to Dr. Hueber. Mean lasing times were 29.6 versus 65.8 minutes, respectively, and total operative times were 53 versus 80 minutes, respectively (p<.01 for both). No differences in perioperative complications between the two systems were observed.

The HPS-120W system revealed linearly increasing mean operative time, mean laser time, and energy usage with increasing prostate sizes, underlining the relevance of evaluating prostate volume with transrectal ultrasound (TRUS sizing).

“TRUS sizing is an important part of the preoperative evaluation of GreenLight PVP, as it has direct implications for the operating parameters. We recommend its use for all laser surgeons to plan operative time and select patients appropriately,” Dr. Hueber said.

He also noted that while the number of fibers used with the older HPS laser system increased dramatically in larger prostates that required longer operative times, the MoXy fibers used in the new XPS system demonstrated greater durability, averaging one fiber per case usage, even in larger prostates. This cost-effective advantage was a further improvement over the HPS-120W laser system.

“The XPS 180W is more efficient than the HPS with regards to laser and total operative time,” Dr. Hueber said. “The XPS MoXy fiber durability allows one-fiber-per-case usage regardless of prostate size, further adding a cost-effective advantage to the XPS system. Since the prostate volume strongly influences all of the operative parameters, we strongly advise pre-operative TRUS prostate volume measurement, as it is an important predictive factor.”

Complete results of the study will soon be published in Urology, Dr. Zorn said.

Dr. Zorn and several of his co-authors are consultants/advisers for American Medical Systems, and two of his co-authors are investigators and/or meeting participants/lecturers for American Medical Systems.UT