Clinical Studies and Guidelines

• European Association of Urology (EAU) Guidelines 5.3.4.1 LUTS, Europe: The European Association of Urology guidelines for managing lower urinary tract symptoms (LUTS) in men caused by benign prostatic hyperplasia (BPH) state with Level 1 evidence: “Aquablation therapy may be offered to patients with moderate to severe LUTS and prostate sizes of 30–80 cc as an alternative to transurethral resection of the prostate (TURP).”

• American Urological Association (AUA) Guidelines s.39 LUTS, USA: The American Urological Association mentions in its guidelines on the surgical management of LUTS due to BPH that Robotic Waterjet Treatment (Aquablation) can be offered as an alternative therapy for patients with prostates sized 30–80 cc with Level C evidence.

• National Institute for Health and Care Excellence (NICE), UK, 2023, IPG770 (www.nice.org.uk/guidance/ipg770): Aquablation therapy has received the highest reimbursement level from NICE and is recommended for prostates of all sizes. It highlights as a key advantage the preservation of sexual function in a large percentage of men, noting the procedure does not use heat to remove hyperplastic prostate tissue, thus eliminating the risk of thermal injury complications. Experts and the committee noted significant improvement in LUTS symptoms and preservation of sexual function, including ejaculation.
• National Institute for Health and Care Excellence (NICE), UK, 2023, MIB315 (www.nice.org.uk/guidance/mib315): This guideline emphasizes Aquablation’s avoidance of heat use and applicability for prostates of any shape and size. Experts pointed out that the technology is innovative compared to conventional treatments, offering increased chances of preserving sexual function and allowing for outpatient treatment. Aquablation appears equally effective as TURP.
• Japanese Urological Association (JUA) Guidelines, Japan: The Japanese Urological Association includes Robotic Aquablation therapy as one of the surgical options for LUTS due to BPH.

Key Studies Worth Mentioning:

• Water Study (double-blind, prospective, multicenter, randomized clinical trial comparing Aquablation to TURP, NCT02505919), USA and Canada, 2023, 5-year results: Aquablation was equally effective as TURP for treating LUTS symptoms, with the added benefit of a higher rate of sexual function preservation.
• Water II Study (prospective multicenter study, NCT03123250), USA and Canada, 2023, 5-year results: Aquablation is safe and effective, providing long-term relief from LUTS symptoms with low reintervention rates, while maintaining sexual function in men with large prostates (80–150 cc).
• Water III Study (randomized clinical trial, NCT04801381): Results were first presented at the 2025 European Urology Congress in Madrid. The study included 202 men with large prostates (80–180 cc), comparing Aquablation to laser enucleation techniques (HoLEP, ThuLEP). Aquablation showed comparable functional results to laser methods, with significantly lower rates of retrograde ejaculation (14.8% vs 77.1%) and stress incontinence (0% vs 9.1%).
• Open Water Study (prospective, multicenter clinical trial, NCT02974751), 2020: The first multicenter study on Aquablation, demonstrating that the method is safe and effective for treating BPH.
• Focal Bladder Neck Cautery (FBNC) Study, 2021: This study showed that cauterization of the bladder neck significantly reduces the risk of transfusion after treatment, increasing safety.

References:

1. Bhojani N, Bidair M, Kramolowsky E, Desai M, Doumanian L, Zorn KC, Elterman D, Kaufman RP Jr, Eure G, Badlani G, Plante M, Uchio E, Gin G, Paterson R, So A, Roehrborn C, Motola J, Kaplan S, Humphreys M. Aquablation Therapy in Large Prostates (80-150 mL) for Lower Urinary Tract Symptoms Due to Benign Prostatic Hyperplasia: Final WATER II 5-Year Clinical Trial Results. J Urol. 2023 Jul;210(1):143-153. doi: 10.1097/JU.0000000000003483. Epub 2023 Apr 28. PMID: 37115632.
2. Gilling P, Barber N, Bidair M, Anderson P, Sutton M, Aho T, Kramolowsky E, Thomas A, Cowan B, Kaufman RP Jr, Trainer A, Arther A, Badlani G, Plante M, Desai M, Doumanian L, Te AE, DeGuenther M, Roehrborn C. WATER: A Double-Blind, Randomized, Controlled Trial of Aquablation^® vs Transurethral Resection of the Prostate in Benign Prostatic Hyperplasia. J Urol. 2018 May;199(5):1252-1261. doi: 10.1016/j.juro.2017.12.065. Epub 2018 Jan 31. PMID: 29360529.
3. Oumedjbeur K, Corsi NJ, Bouhadana D, Ibrahim A, Nguyen DD, Matta I, Arezki A, Sadri I, Elsherbini T, Bhojani N, Elterman DS, Chughtai B, Helfand BT, Glaser AP, Misrai V, Kaplan S, Gilling P, Barber N, Desai M, Badlani GH, Te AE, Roehrborn CG, Zorn KC. Aquablation versus TURP: 5-year outcomes of the WATER randomized clinical trial for prostate volumes 50-80 mL. Can J Urol. 2023 Oct;30(5):11650-11658. PMID: 37838991.
4. Desai M, Bidair M, Bhojani N, Trainer A, Arther A, Kramolowsky E, Doumanian L, Elterman D, Kaufman RP Jr, Lingeman J, Krambeck A, Eure G, Badlani G, Plante M, Uchio E, Gin G, Goldenberg L, Paterson R, So A, Humphreys M, Roehrborn C, Kaplan S, Motola J, Zorn KC. WATER II (80-150 mL) procedural outcomes. BJU Int. 2019 Jan;123(1):106-112. doi: 10.1111/bju.14360. Epub 2018 Jun 10. PMID: 29694702.
5. Zorn KC, Bidair M, Trainer A, Arther A, Kramolowsky E, Desai M, Doumanian L, Elterman D, Kaufman RP Jr, Lingeman J, Krambeck A, Eure G, Badlani G, Plante M, Uchio E, Gin G, Goldenberg SL, Paterson R, So A, Humphreys M, Roehrborn C, Kaplan S, Motola J, Bhojani N. Aquablation therapy in large prostates (80-150 cc) for lower urinary tract symptoms due to benign prostatic hyperplasia: WATER II 3-year trial results. BJUI Compass. 2021 Oct 28;3(2):130-138. doi: 10.1002/bco2.121. PMID: 35474721; PMCID: PMC8988689.
6. Desai M, Bidair M, Zorn KC, Trainer A, Arther A, Kramolowsky E, Doumanian L, Elterman D, Kaufman RP Jr, Lingeman J, Krambeck A, Eure G, Badlani G, Plante M, Uchio E, Gin G, Goldenberg L, Paterson R, So A, Humphreys M, Roehrborn C, Kaplan S, Motola J, Bhojani N. Aquablation for benign prostatic hyperplasia in large prostates (80-150 mL): 6-month results from the WATER II trial. BJU Int. 2019 Aug;124(2):321-328. doi: 10.1111/bju.14703. Epub 2019 Mar 29. PMID: 30734990.
7. Assad A, Nguyen DD, Barber N, Bidair M, Gilling P, Anderson P, Badlani G, Humphreys M, Kaplan S, Kaufman R, So A, Paterson R, Desai M, Roehrborn C, Chughtai B, Zorn KC, Elterman D, Bhojani N. WATER vs WATER II 3-Year Update: Comparing Aquablation Therapy for Benign Prostatic Hyperplasia in 30-80 cc and 80-150 cc Prostates. Urology. 2022 Jul;165:268-274. doi: 10.1016/j.urology.2022.04.004. Epub 2022 Apr 22. PMID: 35469810.
8. Nguyen DD, Barber N, Bidair M, Gilling P, Anderson P, Zorn KC, Badlani G, Humphreys M, Kaplan S, Kaufman R, So A, Paterson R, Goldenberg L, Elterman D, Desai M, Lingeman J, Roehrborn C, Bhojani N. WATER versus WATER II 2-Year Update: Comparing Aquablation Therapy for Benign Prostatic Hyperplasia in 30-80-cm³ and 80-150-cm³ Prostates. Eur Urol Open Sci. 2021 Jan 31;25:21-28. doi: 10.1016/j.euros.2021.01.004. PMID: 34337500; PMCID: PMC8317818.
9. Nguyen DD, Barber N, Bidair M, Gilling P, Anderson P, Zorn KC, Badlani G, Humphreys M, Kaplan S, Kaufman R, So A, Paterson R, Goldenberg L, Elterman D, Desai M, Lingeman J, Roehrborn C, Bhojani N. Waterjet Ablation Therapy for Endoscopic Resection of prostate tissue trial (WATER) vs WATER II: comparing Aquablation therapy for benign prostatic hyperplasia in 30-80 and 80-150 mL prostates. BJU Int. 2020 Jan;125(1):112-122. doi: 10.1111/bju.14917. Epub 2019 Nov 8. PMID: 31599044; PMCID: PMC6972548.
10. Berjaoui MB, Nguyen DD, Almousa S, Daher K, Barber N, Bidair M, Gilling P, Anderson P, Zorn KC, Badlani G, Humphreys M, Kaplan S, Kaufman RP Jr, Elterman D, Desai M, Roehrborn C, Bhojani N. WATER versus WATER II 5-year update: Comparing Aquablation therapy for benign prostatic hyperplasia in 30-80-cm³ and 80-150-cm³ prostates. BJUI Compass. 2024 Sep 9;5(11):1023-1033. doi: 10.1002/bco2.430. Erratum in: BJUI Compass. 2024 Dec 30;5(12):1324-1329. doi: 10.1002/bco2.482. PMID: 39539565; PMCID: PMC11557270.
11. Bach T, Gilling P, El Hajj A, Anderson P, Barber N. First Multi-Center All-Comers Study for the Aquablation Procedure. J Clin Med. 2020 Feb 24;9(2):603. doi: 10.3390/jcm9020603. PMID: 32102329; PMCID: PMC7073705.
12. Elterman DS, Foller S, Ubrig B, Kugler A, Misrai V, Porreca A, Abt D, Zorn KC, Bhojani N, Kriteman L, Mehan R, McDonald M, Kaplan SA. Focal bladder neck cautery associated with low rate of post-Aquablation bleeding. Can J Urol. 2021 Apr;28(2):10610-10613. PMID: 33872559.
13. Raster G, Helfand BT. Aquablation Safety and Outcomes Among Men With Prostate Cancer. Urology. 2025 Jan 30:S0090-4295(25)00107-4. doi: 10.1016/j.urology.2025.01.058. Epub ahead of print. PMID: 39892568.
14. Teoh JYC, Yuen SKK, Lau BSY, Lai FPT, Lee KL, Chiu PKF, Yee CH, Ng CF. Robotic Waterjet Resection for Men With Prostate Cancer Suffering From Lower Urinary Tract Symptoms. Urology. 2025 Jan 14:S0090-4295(25)00034-2. doi: 10.1016/j.urology.2025.01.020. Epub ahead of print. PMID: 39818305.
15. Elterman D, Gilling P, Roehrborn C, Barber N, Misrai V, Zorn KC, Bhojani N, Te A, Humphreys M, Kaplan S, Desai M, Bach T. Meta-analysis with individual data of functional outcomes following Aquablation for lower urinary tract symptoms due to BPH in various prostate anatomies. BMJ Surg Interv Health Technol. 2021 Jun 23;3(1):e000090. doi: 10.1136/bmjsit-2021-000090. PMID: 35047807; PMCID: PMC8749268.
16. Omidele OO, Siegal AS, Roshandel R, Te AE, Kaplan SA. Aquablation at 4-years: Real World Data From the Largest Single-center Study With Associated Outcomes Follow-up. Urology. 2024 Dec;194:216-220. doi: 10.1016/j.urology.2024.07.047. Epub 2024 Jul 30. PMID: 39084348.
17. Ritter M, Stein J, Barber N, et al. WATER III: Aquablation vs. Transurethral laser enucleation of large prostates (80-180ml) in benign prostatic hyperplasia. Presented at 40^th Annual European Association of Urology Congress. Madrid, Spain. March 21-24, 2025. Abstract GC4.