Patient description: The patient is a 63-year-old man presenting to the Emergency Department with a history of acute urinary retention in the past 2 days. Abdominopelvic CT scan revealed a large prostate and a bladder filled with urine. He is a candidate for urethral catheterization and TURP. Further evaluation revealed: Post-void residual: 71 mL Prostate volume (TRUS): 63 mL Prostate-specific antigen (PSA) level: 3.5 ng/mL His recent blood chemistry (3 days ago) was normal: Hgb: 13.6 g/dl WBC: 133000 /mm3 Plt: 370000 /ml PT: 12 second PTT: 34 second INR: 0.9 Creatinine: 0.5 mg/dl BUN: 10 mg/dl U/A: Color: yellow Appearance: cloudy PH: 5.3 Specific gravity: 1.010 Glc: 100 Nitrite: negative Ketone: none Leukocyte esterase: negative RBC: negative WBC: 2 WBCs/hpf U/C: negative

Clinical trial eligibility criteria: eligible ages (years): 50.0-80.0,  Benign Prostatic Hyperplasia 50 to 80 years of age 2. Baseline IPSS score > 13, and a baseline Quality of Life (Qol) question score > 3 3. Prostate volume 25 cc by Trans Rectal Ultrasound (TRUS), measured within past 90 days 4. Anterior prostatic urethral length 2.5 0 cm by cystoscopy, as measured from bladder neck to verumontanum. TRUS will be accepted as a primary screening measure. 5. Failed or intolerant to medication regimen for the treatment of LUTS  New Zealand only: A maximum of 5 participants in acute or chronic urinary retention may be included in the study provided they meet other entry criteria. exemptions for these patients are described in 4a, 5a and they are exempt from #6. Participants will be excluded from participating in this trial if they meet any of the following 1. Obstructive median prostatic lobe or high bladder neck 2. Urethral stricture, meatal stenosis, or bladder neck obstruction either current, or recurrent requiring 2 or more dilatations 3. Elevated Prostate Specific Antigen (PSA) (age 50-70 PSA ≥4; age 70+ PSA ≥6.5) unless negative biopsy within last 3 months, or a positive biopsy 4. Post-void residual volume (PVR) > 250 ml, if not in acute retention 4a. No maximum post void residual volume required if patient in acute or chronic urinary retention. (New Zealand Only, up to 5 patients) 5. Peak urinary flow rate > 12 ml/second, with ≥ 125 ml voided volume at baseline. 5a. No maximum urinary flow or minimum voided volume required if participant in acute or chronic urinary retention. (New Zealand Only, up to 5 patients) 6. History of chronic urinary retention. (New Zealand Only, up to 5 patients) 7. History of neurogenic bladder 8. Compromised renal function (e.g., serum creatinine > 1.8 mg/dl) 9. Concomitant Urinary Tract Infection (UTI) 10. Concomitant bladder stones 11. Confirmed or suspected prostate/bladder cancer 12. Previous pelvic irradiation or radical pelvic surgery 13. Previous prostate surgery, stent implantations, laser prostatectomy, hyperthermia or another invasive treatment to the prostate 14. Chronic prostatitis, or recurring prostatitis within the past 12 months 15. Serious concurrent medical conditions such as uncontrolled diabetes 16. Known allergy to nickel 17. Life expectancy less than 12 months 18. Use of concomitant medications (e.g., anticholinergics, antispasmodics or antidepressants) affecting bladder function 19. Anti-coagulant, anti-platelet, or thrombolytic medication other than Acetylsalicylic Acid (ASA) or Clopidogrel. ASA and Clopidogrel must be ceased 7 days prior to the procedure. 20. 5--reductase inhibitors within 6 months of pre-treatment evaluation unless evidence of same drug dose for at least 6 months with a stable voiding pattern (the drug dose should not be altered or discontinued for entrance into or throughout the study). 21. -blockers within 2 weeks of pre-treatment evaluation unless evidence of same drug dose for at least 6 months with a stable voiding pattern (the drug dose should not be altered or discontinued for entrance into or throughout the study). 22. Future fertility concerns 23. Any severe illness that might prevent study completion or would confound study results