EXPERIMENTAL COMPARISON OF HIGH POWER (80 W) POTASSIUM TITANYL PHOSPHATE LASER VAPORIZATION AND TRANSURETHRAL RESECTION OF THE PROSTATE

Overview of Benchtop Models for Comparison of Surgical Treatments for Benign Prostatic Hyperplasia

PURPOSE OF REVIEW

Benign prostatic hyperplasia (BPH) is a disease of the lower urinary tract which often requires surgical treatment. Recently, there has been a deluge of new treatment options, rarely validated or compared to current treatments on a benchtop model. The purpose of this review is to examine the literature and report which benchtop models are currently being used, which therapies have been tested on them, and what outcomes are being studied on each model.

RECENT FINDINGS

There are various benchtop models to choose from, each with their unique benefits and drawbacks. Perfused porcine kidney models are used to assess bleeding on the benchtop, ex-vivo human prostate helps to see specific interactions of devices with the prostatic tissue, and all other models have evaluated tissue ablation rates and depth of coagulation. There are currently no synthetic or non-animal tissues being used for this purpose, and surgical techniques such as enucleation, water-jet ablation, prostate stents, and water vapor thermal therapy have no representation in these benchtop tests. Benchtop testing serves an important role in the evaluation and comparison of surgical treatments for BPH. This testing allows these therapies to be objectively compared to one another, helping novel medical devices in their path to market and urologists make treatment decisions. Future directions may include further validation of the animal models currently being used and development of synthetic models which mimic the prostate on the benchtop.

Temporal modulation of optical energy for enhanced photothermal hemostasis of intraoperative bleeding during laser treatment

Intraoperative bleeding during laser treatment of benign prostate hyperplasia (BPH) often impedes cystoscopic vision, necessitating the use of conventional hemostatic devices. This study proposes an optical technique to improve the efficacy of photothermal hemostasis of bleeders during laser prostatectomy by temporally modulating a 532 nm laser beam. A perfused porcine kidney model is established to quantitatively investigate various optical pulse patterns and irradiation modes. Thermal simulations demonstrate a high success rate of complete hemostasis achieved by the modulated 532 nm pulse pattern. In comparison to the irradiation modes typically employed for hemostasis, the modulated 532 nm mode exhibits a short coagulation time and minimal thermal injury. ex vivo and in vivo cystoscopic observations validate the clinical feasibility of the proposed optical energy modulation method to regulate intraoperative bleeding.

GreenLight HPS laser 120 W vs diode laser 300 W vaporization of the prostate for the treatment of benign prostatic hyperplasia in Japanese patients: A prospective, single-center, randomized clinical trial

OBJECTIVES

This study aimed to compare the safety and efficacy of laser vaporization with 532 nm GreenLight High Performance System (HPS) laser 120 W (PVP) and 980 nm diode laser 300 W (CVP) for the treatment of benign prostatic hyperplasia (BPH) in a prospective, single-center, randomized clinical trial.

METHODS

A total of 153 consecutive patients with symptomatic BPH were included; 79 patients were treated with PVP and 74 with CVP. Patients were assessed preoperatively and at 3, 6, and 12 months postoperatively using the International Prostate Symptom Score, quality of life index, peak urinary flow rate, and postvoid residual urine volume. All perioperative and postoperative complications were noted.

RESULTS

There were significant and comparable improvements in each of the outcome variables over a follow-up period of 12 months in both groups. The mean operation/vaporization duration (minutes) was comparable at 74/38 (PVP) and 76/34 (CVP), whereas the mean applied laser energy was significantly higher with CVP than with PVP at 260 vs 195 (kJ), respectively. The mean vaporization rate (mL/min) was not significantly different between the two groups (0.53 PVP vs 0.56 CVP). Immediately after surgery, the rate of recatheterization for urinary retention was significantly higher with CVP than with PVP (17.6% vs 6.8%; P < 0.05).

CONCLUSIONS

Both laser systems provided comparable improvement in the subjective and objective parameters with excellent hemostatic properties. Although our results suggest that both procedures are useful treatment choices, further follow-up is needed to draw definitive conclusions regarding the most ideal laser for treating patients with symptomatic BPH.

Dependence of laser-induced tissue ablation on optical fiber movements for laser prostatectomy

PURPOSE

The aim of the current study was to identify the efficient fiber movements for 532-nm laser prostatectomy.

MATERIALS AND METHODS

532-nm Lithium triborate (LBO) laser light was tested on 120 kidney tissues at three different translational speeds (TS 1, 2, and 4 mm/s) and four different rotational speeds (RS 0.5, 1.0, 1.6, and 2.1 rad/s). The applied power was 120 W at a 2-mm working distance and 60° sweeping angle. Ablation rate and dimensions of resulting ablation craters were measured.

RESULTS

Slower TSs and RSs created deeper and wider ablation craters with thinner coagulation, leading to more efficient ablation performance. Maximal ablation rate was achieved at a TS of 2 mm/s and RSs of 0.5 and 1.0 rad/s. An RS of 0.5 rad/s accompanied surface carbonization for all the TSs. Irrespective of TS, ablation rate became saturated at faster RSs than 1.0 rad/s. Faster TSs or RSs reduced tissue ablation, but increased thermal coagulation due to a shorter interaction time.

CONCLUSIONS

Optimal ablation efficiency occurred at a TS of 2 mm/s and a RS of 1.0 rad/s with a thin coagulation of around 1.0 mm and no or minimal carbonization. Further studies will validate the current findings with prostate tissue and high-power levels for laser prostatectomy.

Enhanced photothermal hemostasis using dual wavelengths in an in vivo leporine kidney model

The current study investigated the hemostatic effect of dual wavelengths on in vivo leporine kidney tissue using 532-nm and 980-nm laser systems. Three irradiation modes, 532 nm, 980 nm, and dual (532 and 980 nm) modes, were compared to test non-contact photothermal hemostasis on 36 bleeders in the kidney models. Each bleeder was flushed with saline during the irradiation. The dual mode achieved complete hemostasis more rapidly than the single modes (4.0 ± 1.4 s for dual vs. no hemostasis for 532 nm and 10.0 ± 1.3 s for 980 nm; p < 0.001). Application of 60 W from the dual wavelengths expanded the surface area of the thermal lesion (up to 60%). In vivo dual-wavelength irradiation achieved more rapid and complete hemostasis with ∼2 mm coagulation depth than the single-wavelength irradiation.

Dual-wavelength-assisted thermal hemostasis for treatment of benign prostate hyperplasia

Laser treatment on a large size of prostate gland often encounters significant bleeding that can prolong the entire procedure and cause urinary complications. The current study investigates the feasibility of dual-wavelength (532 and 980 nm) application to achieve rapid hemostasis for 532-nm laser prostatectomy. Porcine kidney and bleeding phantom models were tested to quantify the degree of the irreversible tissue coagulation and to estimate the time for the complete hemostasis, respectively. The ex vivo kidney testing verifies that the dual-wavelength created up to 40% deeper and 25% wider coagulation regions than a single wavelength does. The bleeding phantom testing demonstrates that due to the enhanced thermal effects, the simultaneous irradiation yields the complete photocoagulation (~11 seconds) whereas 532 or 980 nm hardly stops bleeders. Numerical simulations validate that the combined optical-thermal characteristics of both the wavelengths account for the augmented thermal coagulation. The dual-wavelength-assisted coagulation can be a feasible treatment to entail the rapid hemostasis and to facilitate the laser prostatectomy in an effective manner.

Analysis of Thermally Denatured Depth in Laser Vaporization for Benign Prostatic Hyperplasia using a Simulation of Light Propagation and Heat Transfer (secondary publication)

Background and Aims: Laser vaporization of the prostate is expected as a less invasive treatment for benign prostatic hyperplasia (BPH), via the photothermal effect. In order to develop safer and more effective laser vaporization of the prostate, it is essential to set optimal irradiation parameters based on quantitative evaluation of temperature distribution and thermally denatured depth in prostate tissue. Method: A simulation model was therefore devised with light propagation and heat transfer calculation, and the vaporized and thermally denatured depths were estimated by the simulation model. Results: The results of the simulation were compared with those of an ex vivo experiment and clinical trial. Based on the accumulated data, the vaporized depth strongly depended on the distance between the optical fiber and the prostate tissue, and it was suggested that contact laser irradiation could vaporize the prostate tissue most effectively. Additionally, it was suggested by analyzing thermally denatured depth comprehensively that laser irradiation at the distance of 3 mm between the optical fiber and the prostate tissue was useful for hemostasis. Conclusions: This study enabled quantitative and reproducible analysis of laser vaporization for BPH and will play a role in clarification of the safety and efficacy of this treatment.

A Systematic Review and Meta-Analysis of Functional Outcomes and Complications Following the Photoselective Vaporization of the Prostate and Monopolar Transurethral Resection of the Prostate

Purpose

To perform a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing monopolar transurethral resection of the prostate (MTURP) and photoselective vaporization of the prostate (PVP) in order to provide the most up-to-date and reliable recommendations possible.

Materials and Methods

Relevant RCTs were identified from electronic databases for meta-analysis of the surgical outcomes and complications of MTURP and PVP. Meta-analytical comparisons were made using qualitative and quantitative syntheses. The outcome variables are presented as odds ratios with 95% confidence intervals (CIs).

Results

In total, 11 articles were included in this comparative analysis of PVP versus MTURP. Most of the recently published studies exhibited low risk in terms of quality assessment. MTURP was superior to PVP regarding operative time; however, with regard to catheterization and hospitalization time, the mean differences were -1.39 (95% CI=-1.83~-0.95, p<0.001) and -2.21 (95% CI=-2.73~-1.69, p<0.001), respectively, in favor of PVP. PVP was superior to MTURP with regard to transfusion rate and clot retention, but no statistically significant differences were found with regard to acute urinary retention and urinary tract infection. The long-term complications of bladder neck contracture and urethral stricture showed no statistically significant differences between PVP and MTURP. Long-term functional outcomes, including the International Prostate Symptom Score and maximum flow rate, likewise did not display statistically significant differences between PVP and MTURP.

Conclusions

Based on our findings, we believe that PVP should be considered as an alternative surgical procedure for treating male lower urinary tract symptoms secondary to benign prostatic hyperplasia.

Effect of multiple-sweeping on ablation performance during ex vivo laser nephrectomy

BACKGROUND AND OBJECTIVE

Fiber-assisted laser surgery has been employed as a minimally invasive method in various medical fields. In spite of multiple sweeping on tissue during laser treatments, the rate of tissue removal gradually decreases and eventually leads to longer irradiation times as well as deeper thermal injury. The objective of the current study was to quantitatively investigate the effect of multiple fiber sweeps on ablation performance during ex vivo 532-nm laser nephrectomy.

MATERIALS AND METHODS

Porcine kidney tissue was used to evaluate variations in tissue ablation and coagulative necrosis after pre- and multiple-sweeping with a 532 nm wavelength at various fiber speeds (2, 4, and 6 mm/second). The distance between a fiber tip and tissue surface was initially set at 1.5 mm, and no further distance change was performed. Double-integrating spheres in conjunction with an adding-doubling method were employed to measure variations in optical properties of the tested tissue. The extent of ablation and coagulation was quantified to identify the role of multiple-sweeping at various fiber conditions.

RESULTS

Optical property measurements showed a 30% decrease in light absorption but a more than threefold increase in light scattering after irreversible thermal denaturation. Pre-sweeping yielded insignificant effects on tissue coagulation due to almost consistent coagulation depths with numbers of pre-sweeps. Ablation depths increased with more numbers of fiber sweeps and slower fiber speeds whereas coagulation depths thickened primarily with the slower speeds. Multiple-sweeping induced saturation in ablation volume with the increasing numbers of multiple-sweeps irrespective of the fiber speed.

CONCLUSION

A combination of coagulation barriers, spatial distribution of power, and temporal interplay of optical energy could attribute to continuously lessen the amount of the ablated tissue with the multiple sweeps. Optical power modulation with varying fiber conditions (speed and distance) will be examined to optimize surgical parameters and to sustain the equivalent ablation performance of the first sweep with the multiple sweeping for laser nephrectomy. Lasers Surg. Med. 48:616-623, 2016. © 2016 Wiley Periodicals, Inc.

Contemporary review of the 532 nm laser for treatment of benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is a condition that occurs increasingly with age. The established gold standard treatment for BPH has been the electrocautery-based transurethral resection of the prostate (TURP). TURP, however, is associated with several complications and side effects. Therefore, there is an increasing interest in a number of emerging minimally invasive therapies as alterative treatment options. Laser therapy using the Greenlight laser is a promising alternative to the traditional TURP. Selective absorption by hemoglobin allows rapid, hemostatic vaporization of prostate tissue. Additional advantages include avoidance or minimization of complications such as intraoperative fluid absorption, and bleeding, retrograde ejaculation, impotence, and incontinence, as well as its use in treating high volume BPH. We review the use of the Greenlight laser in the treatment of BPH, when comparing complications and advantages in relation to TURP.

A retrospective evaluation of benign prostatic hyperplasia treatment by transurethral vaporization using a 1470 nm laser

OBJECTIVE

This article aims to evaluate the safety and efficacy of a new diode laser at a wavelength of 1470 nm, in the surgical treatment of benign prostatic hyperplasia (BPH).

BACKGROUND DATA

BPH is very common. Laser surgeries, such as photoselective vaporization of the prostate (PVP), have gained interest over the past decade because of their satisfying clinical results and reduced morbidity.

METHODS

A total of 24 patients who underwent transurethral vaporization of the prostate with a new diode laser prototype at a wavelength of 1470 nm were included in this retrospective study. The baseline characteristics of patients and treatment outcomes were evaluated at 4 weeks after the operation with the International Prostate Symptoms Score (IPSS), duration of catheterization, and maximum urinary flow rate (Qmax).

RESULTS

The mean age of patients was 69 ± 8.6 years. The mean time of operation and hospitalization were 97 ± 39 min and 5.3 ± 5.2 days, respectively. The mean duration of catheterization after surgery was 3.1 ± 2.7 days. No recatheterizations or secondary surgeries were required. IPSS and Qmax at 4 weeks postoperatively were significantly changed compared with the baseline (p<0.001).

CONCLUSIONS

Transurethral vaporization of the prostate using a 1470 nm laser is effective to treat benign prostatic hyperplasia.

A prospective, randomized comparative study of monopolar transurethral resection of the prostate versus photoselective vaporization of the prostate with GreenLight 120-W laser, in prostates less than 80 cc

OBJECTIVE

In this study we aimed to compare photoselective vaporization (PVP) with the GreenLight 120-W Laser and monopolar transurethral resection as surgical treatments of prostates less than 80 cc in men with obstructive benign prostatic hyperplasia.

METHODS

From February 2009 to March 2012 we allocated 101 patients with a prostate glands of less than 80 cc; patients were randomly assigned for surgical treatment with monopolar transurethral resection of the prostate (TURP) (n = 62) or PVP (n = 39). Serum prostate specific antigen (PSA), International Prostate Symptom Score (IPSS), Sexual Health Inventory for Men (SHIM), maximum flow rate (Qmax) postmicturition residual (PMR), transrectal ultrasound volumes (TRUS), postvoid urine residual (PVR), complications, re-operations and hospitalization time were collected. The patients were seen in the follow up at 6, 12 and 24 months.

RESULTS

Median age was 69 (56-87) years old in the TURP group and 67 (51-87) years old in the PVP group. Mean preoperative prostate volume was 55 cc (40-72) and 60 cc (41-75) cc in the TURP group versus the PVP group. There was no statistically difference in subjectively (IPSS, SHIM) and objectively (Qmax-PMR) parameters and postoperatively complication rates between the two groups (p > 0.05). A significant difference was observed in the PVP group with a 2 (1-4) days hospital stay compared with 5 (3-9) days for the TURP group (p  < 0.001).

CONCLUSION

Prostate PVP and TURP are effective surgical treatments for benign prostatic hyperplasia. Postoperative functional improvements were durable and equivalent in the two groups. The two techniques have a similar complication rate.

Ex vivo efficacy evaluation of laser vaporization for treatment of benign prostatic hyperplasia using a 300-W high-power laser diode with a wavelength of 980 nm

BACKGROUND AND OBJECTIVE

Laser vaporization of the prostate is considered to be a promising treatment for benign prostatic hyperplasia (BPH), and efficiency of vaporization and hemostasis are both important parameters for such treatment. In this study, we used a high-power laser diode with a wavelength of 980 nm to obtain high vaporization efficiency with good hemostasis. The objective of this study is to evaluate the efficacy of laser vaporization for treatment of BPH in ex vivo experiments using a 300-W high-power laser diode with a wavelength of 980 nm quantitatively.

MATERIALS AND METHODS

An ex vivo experimental setup simulating clinical treatment situation was constructed. Bovine prostate tissue was used as a sample. The power setting was 100, 150, 200, 250, or 300 W, and the irradiation time was 0.5, 1, or 2 s. After laser irradiation, vaporized and coagulated depths were measured.

RESULTS

The vaporized depth increased with the laser power and irradiation time, and the results confirmed that the high-power laser diode could efficiently vaporize the prostate tissue. Coagulated depth increased as the laser power became higher.

CONCLUSIONS

Laser vaporization of prostate tissue using a high-power laser diode with a wavelength of 980 nm represents a promising treatment for BPH; this method exhibits high vaporization efficiency and good hemostasis. However, operators must be aware of the risk of postoperative perforation of the prostatic capsule caused by coagulation of deep regions that cannot be visualized by endoscopic observation.

The volume of prostate can impact the male sexual function following photoselective vaporization of the prostate: results of a prospective analysis of 128 patients with 2-year follow-up

OBJECTIVE

To evaluate the impact of the male sexual function following photoselective vaporization of the prostate treatment in different volume of prostates.

METHODS

One hundred and twenty-eight consecutive patients with active sexual ability who underwent prostate vaporization with the green light laser during 2009-2011 were enrolled. We divided all patients into two groups group I (<70 ml, n = 58) and group II (≥ 70 ml, n = 70) according to the volume of prostate. Two group patients were assessed by International Index of Erectile Function (IIEF-5) preoperatively and at 1, 3, 6, 12, and 24 months. We measured the IPSS, QoL, Q max, PRV PSA at the baseline, postoperation and every visit. IIF-5 questionnaires were also collected in every visit.

RESULT

One hundred and twenty-eight patients were under successful operations. In the 1, 3, 6, 12 and 24 months, main parameters following operation such as Q max PRV IPSS and QoL scores had significant improved compared to baseline. However, the group II was better than group I in every visits. As the 6, 12 and 24 months of questionnaires, group II had less IIEF scores than group I. To evaluate the adverse sexual outcomes of IIEF-5 lists, the erectile dysfunction and overall unsatisfied scores of group II were much more than group I in 6-24-month visits.

CONCLUSION

The larger volume of prostate (≥ 70 ml) following PVP treatment has negative influence on sexual function in the long term (more than 6 months). The adverse sexual outcomes were significant increased after PVP in the prostate with more than 70-ml volume.

The safety and efficacy of aspirin intake in photoselective vaporization laser treatment of benign prostate hyperplasia

Endoscopic surgical treatment has become an option to treat benign prostate hyperplasia. We evaluated the safety and effectiveness of photoselective vaporization of the prostate (PVP) in patients. We evaluated preoperative and perioperative parameters, functional outcomes, and adverse events up to 12 months postoperatively of patients on oral anticoagulation therapy undergoing PVP, and compared the results with patients who did not take anticoagulation therapy. A total of 89 patients who received photoselective vaporization laser for benign prostate hyperplasia from May 2006 to February 2011 in our hospital were enrolled in our study. The patients were divided into two groups based on whether or not they were taking oral aspirin; 23 (25.8%) patients were taking aspirin derivatives (aspirin group), and 66 (74.2%) were not taking aspirin derivatives (control group). The mean prostate volume (58.8 mL vs 51 mL; P = 0.16) and mean energy consumption (235,268 J vs 289,793 J; P = 0.097) were comparable between the aspirin group and control group. The average postoperative results of hemoglobin were 13.4 mg/ dL for the aspirin group versus 13.9 mg/dL for the control group (P = 0.327). A significantly higher maximum flow rates and 80% improved post-void residual urine were noted during the followup. Postoperatively all variable showed significant improvement starting at month 1 of followup and remained improved for the 12 month followup. Postoperative complications were low and comparable between groups. PVP was characterized by excellent hemostatic properties and a very low intraoperative complication rate, even in the patients who were taking aspirin. On the basis of our perioperative results, we recommend PVP as a safe and effective procedure for patients with symptomatic benign prostate hyperplasia when taking an aspirin derivative.

Effect of an employer-sponsored health and wellness program on medical cost and utilization

The objective of this study was to examine the impact of PepsiCo's health and wellness program on medical cost and utilization. The authors analyzed health plan and program data of employees and dependents 19-64 years of age, who had 2 years of baseline data (2002 and 2003) and at least 1 year of data from the intervention period (2004 to 2007), resulting in a sample of 55,030 members. Program effects were measured using a difference-in-difference approach based on a multivariate regression model with an individual-level random effect. In its first year, the program was associated with a relative increase in per member per month (PMPM) cost ($66, P<0.01); a relative reduction in PMPM costs of $76 (P<0.01) and $61 (P<0.01) was seen in the second and third year, respectively. Over all 3 years, the program was associated with reduced PMPM costs of $38 (P<0.01), a decrease of 50 emergency room visits per 1000 member years (P<0.01), and a decrease of 16 hospital admissions per 1000 member years (P<0.01). The disease management component reduced PMPM costs by $154 (P<0.01), case management increased PMPM costs by $2795 (P<0.01), but no significant effects were observed for lifestyle management over the 3 intervention years. The implementation of a comprehensive health and wellness program was associated with a cost increase in the first year, followed by a decrease in the following years. These results highlight the importance of taking a long-term perspective when implementing such programs and evaluating their effectiveness.

[Treating cervico-urethral obstructions with laser diode: initial clinical experience]

BACKGROUND

The first laser employment for the treatment of the cervico-urethral obstructions (CUO) dates back to the early '90s. This study begins with the analysis of laser basics in Medicine and has the purpose to weigh pros and cons (and limits as well) of laser use in CUO due to Benign Prostatic Hyperplasia (BPH). That is an ageing man's typical disease and there is a huge need of minimally invasive treatments, because people affected by this kind of illness suffer very often from comorbidities, and that could make traditional surgery quite risky.

AIM OF THE STUDY

The target of this study is the in vivo experimentation of a brand new laser diode, crated to be specifically used in BPH, and to verify its efficacy and safety.

MATERIALS AND METHODS

The subject of the study is the whole laser diode supply, with its double-band laser source (980 nm + 1470 nm), which gains a 140 W-power and is equipped with Water-Free optical fibers of different kinds of tip. We have tested a conical tip fiber on a standard 24-26 F-resectoscope instead of a standard diathermic loop. The conic fiber optimizes the energy on the treated tissue. We recruited 14 patients with CUO caused by BPH, 56 to 70 years old, with a prostatic volume between 33 and 53 cc, and we treated them with laser surgery using the power of 100-110 W. We considered the operative time, the intra-surgery complications and the specific side effects such as hematuria, pain, catheter removal time and the presence or not of acute urinary retention, in order to evaluate the efficacy and safety of this new technique.

RESULTS

The possibility of using the same resectoscope as the one used in transurethral resection of prostate (TURP) made everything more comfortable and easy because of the immediate feeling with the new instrument and the actual time of Light Vaporization between 30 and 40 minutes, which is more or less the same time of a standard TURP procedure.

CONCLUSIONS

The idea of a double-band-emitting laser used with conical tip fibers appears to be a great solution in the BPH treatment: it uses the principle of low power density plasma in order to treat bigger prostatic tissue areas but never going in depth. In our clinical results, the efficacy of the double-band-emitting laser source (1470 nm + 980 nm) appears to be similar, but even potentially greater, to the actual surgical laser options (such as HoLEP with Ho:YAG laser and PVP with KTP laser), and it is also similar to traditional TURP.

Angular effect of optical fiber movement on endoscopic laser prostatectomy

BACKGROUND AND OBJECTIVE

The optimal fiber manipulation during laser prostatectomy has been highlighted as a critical element to achieve desirable clinical outcomes. However, scientific understanding of the physical interplay between fiber movement and ablative tissue response is still lacking. The objective of this study was to quantitatively investigate the effect of angular movement of an optical fiber on tissue ablation performance.

STUDY DESIGN/MATERIALS AND METHODS

Porcine kidney was employed as a tissue model in vitro. A 180 W 532 nm surgical laser with 750 µm side-firing fibers was utilized to mimic clinical laser prostatectomy. The effect of fiber manipulation parameters on the tissue such as irradiance, number of overlapping pulses (OP), and beam path length (BPL) was assessed at various fiber sweeping (rotational) angles ranging from 0° to 120°. Morphological properties of the post-irradiated tissue were also evaluated in light of ablation depth, coagulative necrosis, and volumetric ablation density (VAD).

RESULTS

As sweeping angle (SA) increased, both laser irradiance and number of OP decreased but BPL increased. Ablation depth was maximized (5.4 ± 1.0 mm) at SAs less than 30° but decreased at higher SAs. The SAs of 15° and 30° demonstrated the minimal thickness of denaturized tissue (0.74 ± 0.14 mm) and VAD (total laser energy/ablation volume (AV) ≈ 4.6 ± 0.46 J/mm(3) ). Decreasing depth and increasing tissue coagulation associated with increasing SA resulted from substantial reduction in both beam irradiance and number of OP, eventually impeding ablation process. Excessive tissue denaturation also occurred when no rotational motion was applied to the fiber possibly due to plume shielding.

CONCLUSION

Inefficient tissue ablation could lead to adverse post-operative complications due to unwanted thermal injury to peripheral tissue. A SA of 30° was found to be desirable for effective tissue ablation, and further clinical investigations will validate the current findings.

Photoselective vaporization of the prostate using GreenLight 120-W lithium triborate laser to treat symptomatic benign prostatic hyperplasia: A single-centre prospective study

OBJECTIVE

We evaluated the safety and efficacy of photoselective vaporization of the prostate (PVP) using GreenLight 120-W lithium triborate (LBO) laser to treat symptomatic small-to-medium sized benign prostatic hyperplasia (BPH).

METHODS

This prospective non-controlled observational study included symptomatic BPH men ≥50 years with international prostate symptom score (IPSS) ≥14, prostate volume (PV) ≤80 cc and maximum flow rate (Q-max) ≤15 mL/s. PVP was performed using the GreenLight 120-W LBO laser machine. Patients were assessed at baseline and postoperatively at discharge, 2 weeks, and 3, 6 and 12 months. We measured changes in IPSS, PV, PSA, Q-max, post-void residual (PVR), hemoglobin (Hb), serum sodium (Na+) and reported complications. Statistical significance was p < 0.05.

RESULTS

The study included 103 men with mean age of 67 (±standard deviation)±9.7 years. Thirty patients were on indwelling urethral catheters for refractory urinary retention and 12 on ongoing anticoagulants. The mean baseline IPSS, PV, PSA, Q-max and PVR parameters significantly improved at follow-up (p < 0.001; each). Mean measurements at baseline versus at six months were: IPSS 25.6 ± 4.2 vs. 7.4±2.3; PV 44.6 ± 9.2 vs. 21.6 ± 6.3 cc (51.6% reduction); Q-max 5.8 ± 3.4 vs. 20.4 ± 4.8 mL/s; PVR 110 ± 40 vs. 35 ± 9 cc. Mean baseline Hb and serum Na+ declined non-significantly (p > 0.05) at discharge and at 2 weeks. No patient needed a blood transfusion. Secondary procedures were needed in 2 patients for urethral and bladder neck strictures. The re-treatment rate for residual adenoma was 0.97%.

CONCLUSION

PVP using the GreenLight 120-W LBO laser to treat small-to-medium sized symptomatic BPH demonstrated significant improvements in efficacy parameters and high safety profile within 12 months of follow-up. The procedure entails good hemostasis with minimal blood loss even in patients receiving ongoing anticoagulants.

Potassium-titanyl-phosphate laser photoselective vaporization for benign prostatic hyperplasia: 5-year follow-up from a district general hospital

BACKGROUND AND PURPOSE

The 80-W potassium-titanyl-phosphate (KTP) laser photoselective vaporization of the prostate (PVP) is a minimally invasive surgical option for patients with symptomatic benign prostatic hyperplasia, although evidence of long-term efficacy is limited. We present the long-term outcomes from a heterogeneous patient population.

PATIENTS AND METHODS

We prospectively collected data for all patients who underwent 80-W KTP laser PVP treatment between 2004 and 2005. Evaluation occurred pr-operatively, and then at 3, 6, 12, and 60 months postoperatively. This included International Prostate Symptom Score (IPSS), peak urinary flow rate (Qmax), postvoid residual (PVR) volume, serum prostate-specific antigen measurement, and transrectal ultrasonography-estimated prostate volume.

RESULTS

A total of 115 patients were eligible for analysis, with a mean age of 77 years and mean prostate volume of 55.8 cc. Of these, 74% were operated on for lower urinary tract symptoms, 23% for acute urinary retention, and 3% for chronic retention; 30% of patients were American Society of Anesthesiologists score ≥ 3, and 93% were treated as 23-hour stays. No patients needed blood transfusion, and there were no cases of transurethral resection syndrome. An initial trial-without catheter failed in 11 (9.6%), although 8 of these successfully voided after a further week. At 5-year follow-up, mean Qmax improved from 8.0 ± 5.0 mL to 13.9 ± 7.7 mL and mean IPSS improved from 22 ± 5 to 9 ± 7. There were no cases of urethral strictures, but there was a 3.3% rate of bladder neck stenosis and an overall re-treatment rate of 21% over 5 years.

CONCLUSION

We confirm the long-term durability of the 80-W KTP laser PVP with minimal perioperative morbidity. It is therefore a safe option for high-risk patients with medical comorbidities, although its high reoperation rate may limit its use to this specific patient population.

Potassium-titanyl-phosphate laser vaporization of the prostate: a case series of an unusual complication

Abstract Despite its increasing use in the management of symptomatic benign prostatic hyperplasia, the long-term complications after potassium-titanyl-phosphate photoselective vaporization of the prostate are poorly reported. We describe a rare complication of this technology-calculi formation in the prostatic urethra. All patients presented with visible hematuria and variable lower urinary tract symptoms up to 5 years after the original surgery. In all cases, the calculi were successfully removed endoscopically. Possible causes for this unusual complication are discussed, and the importance of warning patients about this potential long-term complication are highlighted.

New techniques for laser prostatectomy: an update

Traditionally, the gold standard for treatment of BPH has been the electrocautery-based TransUrethral Resection of the Prostate (TURP). However, the number of laser techniques being performed is rapidly increasing. Potential advantages of laser therapy over traditional TURP include decreased morbidity and shorter hospital stay. There are several techniques for laser prostatectomy that continue to evolve. The main competing techniques are currently the Holmium Laser Enucleation of the Prostate (HoLEP) and the 80W 532nm laser prostatectomy. The HoLEP, using the Holmium:YAG laser, has been shown to have clinical results similar to TURP and is suitable for patients on anticoagulation as well as those with large prostates. Disadvantages of this technique are the high learning curve and requirement of a morcellator. When used to treat BPH, studies have demonstrated that, like the HoLEP, the 80W KTP laser is safe and effective in patients with large prostates and in those taking oral anticoagulation. Several studies have compared these two techniques to TURP. Frequently reported advantages of the HoLEP over the 80W laser prostatectomy are the availability after the procedure of a pathology specimen and ability to remove a higher percentage of prostate tissue during resection. However, the transurethral laser enucleation of the prostate addresses these concerns and has shown to have durable outcomes at 2-year follow-up. Two new laser systems and techniques, the thulium laser and the 980nm laser, have emerged recently. However, clinical data from these procedures are in their infancy and large long-term studies are required.

GreenLight HPS laser 120-W versus diode laser 200-W vaporization of the prostate: comparative clinical experience

BACKGROUND AND OBJECTIVE

We present our clinical experiences of two recently introduced vaporization laser systems: the GreenLight High Performance System (HPS) laser (532 nm, 120 W) and the Diolas LFD diode laser (980 nm, 200 W).

MATERIALS AND METHODS

Two laser systems were evaluated to compare their clinical results for the treatment of benign prostatic hyperplasia (BPH). Patients were treated using either the GreenLight HPS laser (n = 84) or the diode laser (n = 55) in a prospective randomized study. The data of International Prostate Symptom Score (IPSS), maximum flow rate (Q(max)), post-void residual urine (PVR), and quality of life score (Qols) were recorded at baseline, 1-, 6-, and 12-month follow-ups. The prostate volume and prostate-specific antigen (PSA) level were assessed at baseline and 6-month follow-up. All complications were also recorded.

RESULTS

There was a statistically significant difference in IPSS, Q(max), PVR, and QoLs in each laser group at the 1-, 6-, and 12-month follow-ups compared with baseline. There was no statistical significant difference in any of these parameters at any follow-up interval between each group. The diode laser demonstrates superior hemostatic properties compared with the GreenLight HPS laser. Postoperative incontinence and postoperative irritative symptoms are more pronounced (P < 0.05) after diode laser prostatectomy. Higher incidence of dysuria with sloughing tissues and epididymitis (P < 0.05) is noted after diode laser prostatectomy. Other complications were comparable for both procedures.

CONCLUSIONS

Although both lasers can improve subjective and objective parameters of BPH, both can produce undesired effects. The search for the ideal vaporization laser to treat BPH still continues.

Resuscitation of warm ischaemia predamaged porcine kidneys by fibrinolytic preflush with streptokinase: reduction of animal experiments

In order to reduce the number of animal experiments, the use of non-heart-beating donors (NHBDs) from a commercial abattoir has been proposed. Since the use of slaughterhouse organs is legally not defined as animal experiment, this would fulfil international standards as an alternative to animal experiments. The development of intravascular thrombosis after cardiac arrest negatively impacts organ preservation and thus viability during ischaemic storage and reperfusion. A fibrinolytic preflush with streptokinase might overcome these limitations. Therefore, the functional and histomorphological integrity of kidneys preserved immediately with intact circulation (control group A) and kidneys preserved after cardiac arrest with a 30 min period of warm ischaemia (WI) (group B) was compared with kidneys preflushed with 12.5 kU/L (group C) or 50 kU/L streptokinase (group D) after 30 min WI prior to preservation. We could demonstrate that kidneys preflushed with 12.5 kU/L streptokinase (group C) performed better than those without streptokinase pretreatment after WI (group B). Parameters like oxygen consumption, perfusion pressure, laboratory values, lactate dehydrogenase level and lipidperoxidation were closer to that of the control (group A) than in groups B and D. The higher streptokinase concentration of 50 kU/L (group D) resulted histologically in a more pronounced tissue damage and an attenuated renal function, indicating toxic effects. On the basis of our results we believe streptokinase preflushed slaughterhouse kidneys to be an adequate alternative to organs from laboratory animals with the potential to further reduce the number of animal experiments.

Current laser treatments for benign prostatic hyperplasia

The latest technical improvements in the surgical armamentarium are remarkable. In particular, advancements in the urologic field are so exceptional that we could observe the flare-up of robot-assisted laparoscopic radical prostatectomy for prostate cancer and laser prostatectomy for benign prostatic hyperplasia (BPH). Photoselective vaporization of the prostate (PVP) and holmium laser prostatectomy are the most generalized options for laser surgery of BPH, and both modalities have shown good postoperative results. In comparison to transurethral prostatectomy (TURP), they showed similar efficacy and a much lower complication rate in randomized prospective clinical trials. Even in cases of large prostates, laser prostatectomy showed comparable efficacy and safety profiles compared to open prostatectomy. From a technical point of view, PVP is considered to be an easier technique for the urologist to master. Furthermore, patients can be safely followed up in an outpatient clinic. Holmium laser enucleation of the prostate (HoLEP) mimics open prostatectomy because the adenomatous tissue is peeled off the surgical capsule in both procedures. Therefore, HoLEP shows notable volume reduction of the prostate similar to open prostatectomy with fewer blood transfusions, shorter hospital stay, and cost reduction regardless of prostate size. Outcomes of laser prostatectomy for BPH are encouraging but sometimes are unbalanced because safety and feasibility studies were reported mainly for PVP, whereas long-term data are mostly available for HoLEP. We need longer-term randomized clinical data to identify the reoperation rate of PVP and to determine which procedure is the ideal alternative to TURP and open prostatectomy for each patient.

Impact of prostate volume on the efficacy of high-power potassium-titanyl-phosphate photoselective vaporization of the prostate: a retrospective, short-term follow-up study on evaluating feasibility and safety

PURPOSE

We determined the impact of prostate volume on the efficacy of the high-power (80 W) potassium-titanyl-phosphate (KTP) photoselective laser vaporization of the prostate in men with lower urinary tract symptoms (LUTS).

MATERIALS AND METHODS

Patients were stratified into 3 groups according to prostate volume: '< 40 g' (n = 49) and '40-59 g' (n = 49) and '≥ 60 g' (n = 22). Median follow-up was 9 months (range 6 to 21).

RESULTS

No differences in age and follow-up duration were observed in the three groups. At baseline, no significant differences were noted in the three groups in terms of the International Prostate Symptom Score (IPSS) (21.4, 19.4 and 19.1; p = 0.412) as well as the maximum flow rate (Qmax) (10.2, 9.2, and 8.6 mL/s; p = 0.291) and post-void residual (PVR) (66.2, 80.4, and 71.5 mL; p = 0.856). The mean operative times were 30.9, 46.9, and 58.6 minutes (p< 0.001) and total median energy deliveries for each group were 62.3, 97.6, and 135.9 kJ, respectively (p< 0.001). No severe intraoperative complication was observed. At the last follow-up, these parameters improved significantly regardless of prostate volume, and the IPSS (11.1, 9.4, and 12.3; p = 0.286) as well as Qmax (15.9, 15.9, and 14.2 mL/s; p = 0.690) and PVR (33.7, 28.4, and 14.2 mL; p = 0.395) were not significantly different among the groups.

CONCLUSION

Although a larger prostate requires more time and energy delivery, photoselective laser vaporization of the prostate is safe and efficacious for patients with LUTS regardless of prostate volume.

120 W lithium triborate laser for photoselective vaporization of the prostate: comparison with 80 W potassium-titanyl-phosphate laser in an ex-vivo model

PURPOSE

To evaluate the ablative and hemostatic properties of the recently introduced 120 W lithium triborate (LBO) 532 nm laser and compare the results against the conventional 80 W potassium-titanyl-phosphate (KTP) laser.

MATERIALS AND METHODS

The ex-vivo model of the isolated blood-perfused porcine kidney was used to determine the ablation capacity, hemostatic properties, and coagulation depth of the GreenLight HPS laser system (American Medical System, Minnetonka, MN) that used an output power of 120 W. The results were compared with the KTP laser that used output power levels of 30 W, 50 W, and 80 W. Unperfused kidneys were weighed before and after 10 minutes of laser ablation in an area of 3 x 3 cm; the weight difference marked the amount of removed tissue. Bleeding was determined by the weight difference of a swab before and after it was placed on the bleeding surface for 60 seconds after ablating a surface area of 9 cm(2) on blood-perfused kidneys.

RESULTS

With a tissue removal of 7.01 +/- 1.83 g after 10 minutes of laser ablation at 120 W, the LBO laser offered a significantly higher ablation capacity compared with 3.99 +/- 0.48 g reached with the conventional KTP laser at 80 W in the same time interval (P < 0.05). The bleeding rate was also significantly increased using the LBO at 120 W compared with the conventional device at 80 W (0.65 +/- 0.26 g/min vs 0.21 +/- 0.07 g/min; P < 0.05). The corresponding depths of the coagulation zones were 835 +/- 73 microm and 667 +/- 64 microm (P < 0.05), respectively.

CONCLUSION

The 120 W LBO laser offers a significantly higher tissue ablation capacity compared with the conventional 80 W KTP laser. Because the increased efficacy of the device is accompanied by a higher bleeding rate and a slightly deeper coagulation zone, the user has to select the appropriate output power levels carefully for a safe and efficient treatment. Nevertheless, the bleeding rate compared with previous studies of transurethral resection of the prostate is significantly reduced.

Preliminary results of prostate vaporization in the treatment of benign prostatic hyperplasia by using a 200-W high-intensity diode laser

OBJECTIVES

To evaluate the efficacy and safety of a 200-W high-intensity diode laser in the treatment of benign prostatic hyperplasia.

METHODS

The prostate was vaporized by using a side-firing laser fiber (diode laser: power, 150-200 W; wavelength, 980 nm; Limmer, Germany). The following parameters were assessed at baseline, and after a follow-up period of 1- and 6 months: International Prostate Symptom Score, maximum uroflow rate, postvoid residual urine volume, and quality of life score. Prostate volume and prostate-specific antigen levels were assessed at baseline and 6 months postoperatively.

RESULTS

This study included 55 patients diagnosed with lower urinary tract symptoms secondary to BPH, who were treated between December 2007 and July 2008. The recatheterization rate was 10.9%. None of these patients required a blood transfusion or had transurethral resection syndrome. Statistically significant improvements (P < .001) were observed in the values of International Prostate Symptom Score, Q(max), postvoid residual urine volume, and quality of life score at 1- and 6 months of follow-up as compared with the respective baseline values. Transient urge incontinence was noted in 8 patients (8/55, 14.5%).Sloughing of necrotic tissues was observed on cystoscopy in 8 patients within several weeks or months after the operation. The retreatment rate (secondary transurethral resection of the prostate) was 7.3%.

CONCLUSIONS

From our preliminary data, it was evident that diode laser prostatectomy can achieve excellent hemostasis, and provide immediate relief from obstructive voiding symptoms. However, the postoperative irritative symptoms and sloughing of necrotic tissues remained to be an important issue that needed to be resolved.

The one year outcome after KTP laser vaporization of the prostate according to the calculated vaporized volume

The aim of this study was to develop a new simple method for measuring the vaporized volume and to evaluate the outcome of high-power potassium-titanyl-phosphate (KTP) photoselective laser vaporization. A total of 65 patients, with a mean age of 67.7 yr (range 53 to 85), were included in the primary analysis. The vaporized volume was calculated as the pre-operative volume minus the immediate post-operative volume plus the volume of the defect. For all patients, the subjective and objective parameters improved significantly after surgery. Six and 12 months after surgery, the group with a smaller vaporized volume (<15 g) had a lower reduction of the mean International Prostate Symptom Score (P=0.006 and P=0.004) and quality of life index (P=0.006 and P=0.004) when compared to the group with a greater vaporized volume (>or=15 g). There were no differences in the change of the maximum flow rate and post-void residual based on the vaporized volume. Our findings suggest that the subjective improvement, after a high-power KTP laser vaporization, may be dependent on the vaporized volume obtained after the procedure.

Dystrophic calcification and stone formation on the entire bladder neck after potassium-titanyl phosphate laser vaporization for the prostate: a case report

Dystrophic calcification can be defined as a calcification that occurs in degenerated or necrotic tissue. It is associated with multiple clinical conditions, such as collagen vascular diseases. It involves the deposition of calcium in soft tissues despite no generalized disturbance in the calcium or phosphorus metabolism, and this is often seen at sites of previous inflammation or damage. Potassium-titanyl phosphate (KTP) laser vaporization of the prostate is safe and relatively bloodless procedure that results in a shorter catheterization, immediate symptomatic improvement, and less severe postoperative irritative symptoms. However, longer follow-up studies or reports about complications are lacking. Here in we report a case of dystrophic calcification and stone formation on the entire bladder neck after performing KTP laser vaporization of benign prostate hyperplasia. That was treated by lithotripsy and transurethral resection.

The KTP‐(greenlight‐) laser – principles and experiences

The most recent advance in laser technology for transurethral prostatectomy is represented by the KTP laser. A potassium-titanyl-phosphate-(KTP-) crystal doubles the frequency of pulsed Neodymium: Yttrium-Aluminum-Garnet (Nd:YAG) laser energy to a 532 nm wavelength, which is in the green electromagnetic spectrum (Greenlight-laser) and is selectively absorbed by hemoglobin and not at all by water. Reducing the wavelength leads to a completely different interaction between laser beam and prostatic tissue. In contrast to the early clinical experiences with the Nd:YAG lasers in which vaporization was observed as a side-effect during the procedure, the new KTP laser offers an immediate and efficient vaporization, leading to real tissue ablation. Because of the instant and nearly complete absorption in blood, the depth in vascularized tissue such as prostate is only 0.8 mm. The superficial coagulation prevents the large tissue necrosis that is seen with the Nd:YAG laser, leading to long lasting irritative symptoms due to sloughing of necrotic tissue. Initial experiences, made with a 60W KTP system, demonstrated that the procedure was as effective as conventional transurethral resection of the prostate (TURP) with a lower intraoperative complication rate. In order to speed up vaporization of the prostate laser power has been increased to 80W. The 80W KTP laser combines the tissue debulking properties of TURP and the favourable safety profile of laser surgery. With the new 120W High Performance System, introduced in 2006, vaporization will become more powerful and faster. Initial reports are awaited.

Plasma vaporisation of the prostate: initial clinical results

BACKGROUND

Laser vaporisation of the prostate has had a considerable impact in recent years. In an attempt to achieve tissue vaporisation with bipolar high-frequency generators, plasma vaporisation was recently introduced.

OBJECTIVE

To provide the first clinical information on bipolar plasma vaporisation of the prostate for patients with lower urinary tract symptoms (LUTS) due to bladder outlet obstruction (BOO).

DESIGN, SETTING, AND PARTICIPANTS

Thirty patients were included in this prospective bicentre study.

INTERVENTION

All patients underwent bipolar plasma vaporisation with a novel electrode (Olympus Winter & Ibe GmbH, Hamburg, Germany).

MEASUREMENTS

International Prostate Symptom Score (IPSS), bother score, maximum flow rate (Q(max)), and postvoid residual were evaluated at baseline and at the time of discharge as well as at 1, 3, and 6 mo after the intervention.

RESULTS AND LIMITATIONS

Mean preoperative prostate volume was 59±32 ml (range: 30-170), and mean operating time was 61±26 min (range: 20-140). Besides one reoperation (conventional transurethral prostatectomy) due to persistent obstruction, no major complication occurred intra- or postoperatively and no blood transfusion was required. Catheterisation time averaged 41±35 h (range: 18-192). Transient mild to moderate dysuria was noted in four patients (13%). At 1, 3, and 6 mo, Q(max) increased from 6.6±2.7 ml/s preoperative to 17.3±4.7 ml/s (p<0.01), 18.5±4.6 ml/s (p<0.01), and 18.1±5.0 ml/s (p<0.01), respectively. The IPSS decreased from 20.8±3.6 to 10.4±3.5 (p<0.01), 8.2±2.9 (p<0.01), and 8.1±3.1 (p<0.01), respectively. These data represent a small nonrandomised study cohort with limited follow-up.

CONCLUSIONS

Our initial experience indicates that bipolar plasma vaporisation might be a safe and effective treatment option for patients with LUTS due to BOO. To define the potential role of this novel technique, randomised trials with longer follow-up are mandatory.

Prospective single-centre comparison of 120-W diode-pumped solid-state high-intensity system laser vaporization of the prostate and 200-W high-intensive diode-laser ablation of the prostate for treating benign prostatic hyperplasia

OBJECTIVE

To evaluate the safety, efficacy and short-term outcome of a new 980 nm high-intensity diode (HiDi) laser (Limmer Laser, Berlin, Germany) system in comparison to the diode-pumped solid-state laser high-performance system (HPS; GreenLight(TM), AMS, Minnetonka, MI, USA) for treating benign prostatic hyperplasia (BPH) in a prospective non-randomized single-centre study.

PATIENTS AND METHODS

From February to September 2007, 117 consecutive patients with lower urinary tract symptoms secondary to BPH were included; 62 patients were treated with 120-W HPS laser vaporization and 55 with 980-nm HiDi laser ablation of the prostate. We evaluated perioperative variables, and complications during and after surgery. Patients presenting for follow-up completed the International Prostate Symptom Score, and had their maximum urinary flow rate and postvoid residual urine volume measured.

RESULTS

The mean (sd) age of the patients was 72.3 (8.8) years (HiDi) and 73.1 (10.8) years (HPS), with a mean preoperative prostate volume of 64.7 (29.7) and 67.4 (46.9) mL, respectively. The mean operative duration was comparable, at 56.4 (20.2) and 62.7 (36.3) min, respectively, whereas the mean energy delivery was significantly higher with the diode laser, at 313 (132) vs 187 (129) kJ (P < 0.001). For patients treated with the HPS the rate of visual impairment from bleeding was higher (0% vs 12.9%, P < 0.01), as was prostate capsule perforation (0% vs 4.8%, P > 0.05). Soon after surgery the rate of dysuria (23.6% vs 17.7%, P > 0.05) and transient urge incontinence (7.3% vs 0%; P < 0.05) was higher for the HiDi laser. During the follow-up there were higher rates of bladder neck stricture (14.5% vs 1.6%, P < 0.01), re-treatment (18.2% vs 1.6%, P < 0.01) and stress urinary incontinence (9.1% vs 0%; P < 0.05) for the HiDi laser group.

CONCLUSION

Both systems investigated provide good tissue ablative properties. The HiDi laser at 980 nm is more favourable in terms of haemostasis. The penetration depths, resulting in coagulation necrosis and leading to increased re-treatment, bladder neck stricture and incontinence rates, were higher with the HiDi laser.

Photoselective laser vaporization prostatectomy for acute urinary retention in China

PURPOSE

To assess the clinical efficacy and safety of photoselective laser vaporization of the prostate (PVP) in the treatment of patients with acute urinary retention (AUR) secondary to benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

Forty-two patients (mean age 72 +/- 5 years, range 65-89) with AUR because of BPH were treated with a prospective trial of PVP with the potassium-titanyl-phosphate (KTP) laser. The treatment outcome was evaluated with subjective and objective tests at 1, 3, 6, and 12 months after PVP using the International Prostate Symptom Score (IPSS), disease-specific quality of life (QoL) score, postvoid residual (PVR) urine volume, and maximum urinary flow rate (Qmax). The International Index of Erectile Function questionnaire and a self-designed ejaculatory questionnaire were completed at different follow-up times to determine patient satisfaction and changes in sexual function.

RESULTS

After preliminary urine drainage and adequate preoperative preparation, PVP was performed and bladder outlet obstruction was effectively relieved. The mean prostate volume was 62.5 +/- 11.7 cc, and the mean residual volume with retention was 650 mL (range 240-1200 mL). Mean operative time was 28.6 +/- 5.7 minutes. Mean catheterization duration was 5.6 days (range 3-14 d). There was significant subjective improvement of symptoms and objective improvement in urinary flow rates at 12 months. The mean IPSS and QoL score decreased significantly (P < 0.05). Mean PVR volume also decreased. The mean Qmax was 16.2 +/- 4.6 mL/sec after treatment. Only two patients had recurrent urinary retention during follow-up. There were no intraoperative or postoperative adverse events.

CONCLUSIONS

The early clinical results suggest that the PVP is a promising safe, effective, and less-invasive treatment with minimal morbidity for patients with urine retention secondary to BPH.