Aquablation of the Prostate for Symptomatic Benign Prostatic Hyperplasia: Early Results

A scoping review of ejaculatory dysfunction due to surgical treatments for benign prostatic hyperplasia: limitations of available tools for assessment and reporting

INTRODUCTION

Clinicians primarily focus on the presence or absence of anterograde ejaculation following surgery for benign prostatic hyperplasia (BPH). Failing to assess dysfunctional ejaculation and associated bother in a granular fashion can underestimate the prevalence and significance of ejaculatory dysfunction in this population.

OBJECTIVES

This scoping review provides critical appraisal of existing tools assessing ejaculatory function and associated bother, emphasizing the importance of adequate history-taking, preoperative counseling, and supplemental questions that should be used prior to and after treatment.

METHODS

A literature review was conducted using pertinent keywords from 1946 to June 2022. Eligibility criteria included men developing ejaculatory dysfunction following BPH surgery. Measured outcomes included the assessment of patient bother related to ejaculatory function, pre- and postoperative scores from the Male Sexual Health Questionnaire (MSHQ). and Danish Prostate Symptom sexual function domain (DAN-PSSsex).

RESULTS

Results of this study included only 10 documented patients' bother due to ejaculatory dysfunction following treatment. Pre- and postoperative MSHQ were used as the diagnostic tool in 43/49 studies, one study documented "preservation of anterograde ejaculation", and one used DAN-PSSsex. Q1-4 of the MSHQ were used in 33/43 studies, 3/43 used Q1, 3, 5-7, 1/43 used solely Q4, 1/43 used Q1-3 + Q6 and Q7, and 5/43 used the entire MSHQ. No studies used post-ejaculation urinalysis to diagnose retrograde ejaculation. Only four studies explicitly documented bother and found 25-35% of patients were bothered with a "lack of ejaculate" or "other ejaculation difficulties" during sexual activity after BPH surgery.

CONCLUSIONS

There are currently no studies stratifying patient bother by various components of ejaculation (force, volume, consistency, sensation of seminal expulsion, painful ejaculation, etc.) after BPH surgery. Opportunities for improvement exist in reporting ejaculatory dysfunction related to BPH treatment. A comprehensive sexual health history is needed. Further investigation into effects of BPH surgical treatments on specific characteristics of the patient's experience of ejaculation is required.

Initial Experience Performing "Cautery Free Waterjet Ablation of the Prostate"

Introduction Herein, we describe our initial experience performing waterjet ablation of the prostate without electrocautery. Methods A retrospective review of patients undergoing Aquablation for BPH between February and September 2019 was performed. A standardized perioperative protocol for optimizing hemostasis was implemented. The primary endpoint was to define bleeding complications perioperatively and up to 30 days postoperatively after Aquablation. Bleeding complications included hematuria requiring prolonged continuous bladder irrigation, drop in hemoglobin requiring transfusion, or take back to operating room for evacuation of bladder clots and bladder fulguration. Bivariable analysis using Fisher's exact test and unpaired t-tests were used to identify factors associated with bleeding complications. Results Thirty-two patients underwent Aquablation over the study period. Average preoperative IPSS was 20 (Range: 13 to 34) and Qmax was 7mL/s (Range: 0 to 11). Mean prostate volume was 65 mL (Range: 30 mL to 200 mL). Average perioperative change in hemoglobin was 1.3 g/dL (Range: -0.3 g/dL to 4.2 g/dL). Eight patients (25%) experienced bleeding complications. Three (9.4%) required blood transfusions. On Fisher's exact test, prostate volume (91 mL vs 55 mL; p = 0.0361) and preoperative prostate specific antigen (6.6 vs 2.9; p = 0.0218) were associated with postoperative bleeding. Conclusions Performing waterjet ablation of the prostate without the use of electrocautery after waterjet treatment to control bleeding resulted in significant bleeding complications (25% of our cohort) during our initial experience. A combination of traction and focal bladder neck electrocautery is the best strategy to minimize bleeding complications after Aquablation.

Informative value of histological assessment of tissue acquired during aquablation of the prostate

PURPOSE

To determine the histological validity of the tissue acquired during aquablation of the prostate.

PATIENTS AND METHODS

Prostatic tissue of 12 patients that consecutively underwent aquablation for benign prostatic enlargement was systematically examined. Histological examination was performed by two experienced uropathologists using a digital slide scanner and slide viewer software (Pannoramic 250 and Case Viewer 2.3, 3D Histech, Hungary). The surface areas of the assessable glands were examined and set in relation to the total surface area of the material available for histology and to the patient's total prostate volume. Examinations were performed analogously in ten consecutive patients undergoing transurethral resection of the prostate (TURP) to facilitate interpretation of the results. Data were analyzed using descriptive statistics.

RESULTS

A median of 4.06% (range 1.43-7.5%) of the preoperative total prostate volume (median 64.5 ml (range 40-80 ml)) was obtained for histological examination by aquablation. Due to severe mechanical destruction and fragmentation, only a proportion of 0.43% (0.06-1.79%) of this tissue represented histologically assessable glands. Therefore, roughly 0.017% of the total prostatic volume was available for a reliable histological examination. In comparison, 32.5% (6.67-37.5%) of the total prostate volume was removed by TURP and 22.86% (7.45-40.57%) of this tissue represented informative prostatic glands, corresponding to 7.43% of the total prostate volume.

CONCLUSION

Histological significance of the tissue obtained by aquablation of the prostate is very limited. Costs and effort of the histological examination must, therefore, be weighed critically against the limited informative value.

Efficacy and safety of aquablation of the prostate for patients with symptomatic benign prostatic enlargement: a systematic review

PURPOSE

The aim of this systematic review is to summarize the contemporary literature on aquablation and evaluate its safety and efficacy for the treatment of symptomatic BPE.

EVIDENCE ACQUISITION

A systematic search of English language literature was performed using the PubMed-MEDLINE and Web of Science libraries up to 24 July 2019 by combining PICO (patient population, intervention, comparison, and outcome) terms. We retrieved 16 studies, including 446 patients treated with aquablation eligible for data extraction and analysis. Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines were followed.

EVIDENCE SYNTHESIS

We identified a randomized controlled trial (RCT) comparing aquablation to transurethral resection of the prostate (TURP) with 6-month, 1-year, and 2-year outcomes, three single-center and single-arm studies, three multicenter and single-arm studies, and five subgroup analyses. Aquablation significantly improved International Prostate Symptom Score (IPSS), IPSS-quality of life (IPSS-QoL), maximum urinary flow rate (Q_max) and post void residual (PVR) from baseline to last follow-up in all prospective studies. At 2-year follow-up, aquablation showed non-inferior symptom relief compared to TURP, with a lower risk of anejaculation favoring aquablation and no significant differences regarding Clavien-Dindo events. Although a significant hemoglobin drop was reported in all aquablation single-arm studies and when compared to TURP, it did not translate into increased transfusion rates.

CONCLUSIONS

Data from the WATER trial demonstrates that aquablation is comparable to TURP in effectively improving symptom scores and functional parameters related to BPE and bladder outlet obstruction. The evidence provided supports the safety of aquablation assessed by procedure-related adverse events.

The Role of Aquablation for the Surgical Treatment of LUTS/BPH

PURPOSE OF REVIEW

To explore the potential applicability of a novel, heat-free, and robotically controlled ablative therapy for surgical management of benign prostatic enlargement.

RECENT FINDINGS

With the emergence of new technology to provide personalized care and overcome the complications associated with options such as TURP, holmium laser enucleation of the prostate, GreenLight laser, or simple prostatectomy, Aquablation has been studied across a variety of prostate volumes. The functional outcome of Aquablation seems to be uncompromised by prostate volume. The sexual profile seems superior to TURP and the risk of retrograde ejaculation is lower. The robotic system provides a reproducible ablation, independent of prostate volume, without requiring extensive training for performing the procedure. The mean ablation time in the prostate as large as 150 ml does not exceed 9.1 min, and the blood transfusion rates do not seem to be higher than open prostatectomy.

What robot for tomorrow and what improvement can we expect?

PURPOSE OF REVIEW

The purpose of this review is to summarize the status of robotic surgery currently, contextualizing the advances and improvements we can expect in the immediate future. Robotics continues to demonstrate increased utility and expansion in medicine, particularly surgery. When coupled with the imminent expiry of Intuitive patents in the next few years, it is timely to consider what we can expect to see from new platforms; what new features might we anticipate and what technology will be available to enhance and improve patient care.

RECENT FINDINGS

There really are no limits with the anticipated developments in the field of medical robotics. Multiple large companies and academic institutions continue to invest in design and production with the release of a number of platforms already having occurred, whereas others are to come in the near future. The main anticipated advances will be haptic feedback, decreased cost, improved theatre assimilation with open consoles permitting free communication and lower theatre footprint. The robot patient interface is to be enhanced with single port platforms in production with a better interface including haptic feedback. The addition of NOTES and smarter flexible robotics is the next key area of interest, whereas the introduction of technology with image guidance and networking where large data sets or connectivity permit increased clinical acumen to enhance decision making.

SUMMARY

We are at the cusp of a tipping point as the intellectual property for the first major robotic system in surgery comes to an end. It is likely to be a period of great opportunity with enhanced surgery and patient outcomes through significant innovation, multiple platforms nearing dissemination, with various technological advances. We anticipate this will yield a great period of innovation and diversity. Will we see a truly automated robot soon; the Smart Tissue Autonomous Robots are the limit.

Comparison of < 100 cc prostates and > 100 cc prostates undergoing aquablation for benign prostatic hyperplasia

INTRODUCTION

Surgical options for benign prostatic hyperplasia (BPH) become limited when treating large prostates due to steep learning curves and less effective treatment. Aquablation (AquaBeam System, PROCEPT BioRobotics, Inc., USA) could remedy this. We compare the effectiveness of Aquablation in large prostates between 80 cc and 100 cc and very large prostates > 100 cc.

METHODS

WATER II (NCT03123250) is a prospective, multicenter, international clinical trial of Aquablation for the surgical treatment of LUTS/BPH in men of age 45-80 years with prostates between 80 cc and 150 cc. Aquablation was performed using the AquaBeam System. The reported analysis compares the subgroup of patients with a baseline prostate size of < 100 cc versus those with a prostate size of > 100 cc. Students' t test was used for continuous variables and Fisher's test for ordinal/binary variables.

RESULTS

Of 114 screened patients, 101 meeting eligibility criteria were enrolled at 13 US and 3 Canadian sites between September and December 2017. Mean operative time was 31.2 ± 8 min in the < 100 cc subgroup and 41.7 ± 14.9 min in the > 100 cc subgroup. The average length of stay following the procedure for the < 100 cc subgroup was 1.5 ± 0.7 days versus 1.7 ± 1.1 days for the > 100 cc subgroup. Mean changes in International Prostate Symptom Score (IPSS), IPSS quality of life, and IPSS voiding and storage subscores were substantial, occurring soon after treatment and averaging (at 3 months) 16.5, 2.8, 10.6, and 5.8 points, respectively (all p < 0.0001).

CONCLUSION

Aquablation clinically normalizes outcomes between patients of the < 100 cc and > 100 cc prostate cohorts. It is safe and effective in patients with large prostate glands (> 100 cc) with a smoother learning curve.

Investigational procedures in benign prostatic hypertrophy

PURPOSE OF REVIEW

As benign prostatic hypertrophy (BPH) becomes a more common disease, there has been a dramatic rise in the number of investigational procedures being developed to manage it. We seek to present an overview of the most recently developed treatments and present clinical data related to application wherever available.

RECENT FINDINGS

As a greater number of treatments become available for BPH, improved diagnostic testing could prove beneficial in helping guide patient selection. Efforts are underway to identify serum biomarkers associated with BPH as well as new classifications strategies, specifically with MRI, to determine both the anatomy of BPH as well as its histologic distribution. Outpatient-based procedures for BPH currently being developed include the temporary implantable nitinol device as well as intraprostatic injections such as Botox and PRX302. Aquablation is a novel technique that uses robotically guided high-pressured saline to ablate prostate tissue. Early data suggests noninferiority compared with TURP. Finally, efforts are underway to apply robotics to BPH with the advent of a robotic transurethral platform being designed for prostate enucleation.

SUMMARY

Many new techniques are poised to be introduced to the BPH market over the coming years. The unique risk/benefit profiles as well as associated clinical outcomes of each will need to be studied in detail in order to help identify proper roles in the management of patients with symptomatic disease.

Aquablation: a novel and minimally invasive surgery for benign prostate enlargement

Aquablation is a minimally invasive surgical technology for benign prostate enlargement, which uses high-pressure saline to remove parenchymal tissue through a heat-free mechanism of hydrodissection. Early results show this to be a promising surgical strategy with a strong morbidity profile and reduced resection time. This review serves to provide an overview of the technique and evaluate its safety and efficacy.