The Zenflow Spring System Safety and Performance Study (ZEST CAN)

Inclusion Criteria:

1. Patient is able and willing to comply with all the assessments of the study
2. Patient or patient's legal representative has been informed of the nature of thestudy, agrees to participate and has signed the informed consent form
3. ≥ 45 years of age
4. Baseline IPSS score > 13
5. Prostate volume 25 - 80 cc and prostatic urethral length between 2.5-4.5 cm measuredwithin the past 90 days
6. Failed, intolerant, or patient choice to not take a medication regimen for thetreatment of LUTS

Exclusion Criteria:

1. Obstructive intravesical median prostatic lobe which in the opinion of the operatorwould not benefit from treatment
2. Urethral stricture, meatal stenosis, or bladder neck obstruction - either current, orrecurrent requiring 2 or more dilations as reported in the patient's history
3. Requiring self-catheterization to void.
4. Baseline PSA > 10 ng/mL or confirmed or suspected prostate cancer
5. Any of the following, taken from a single uroflowmetry reading:
6. Post-void residual volume (PVR) > 250 ml
7. Peak urinary flow rate of > 15 ml/second
8. < 125 ml urinary volume voided at baseline (pre-bladder urinary volume of ≥150 mlrequired)
9. Other condition or disease that might cause urinary retention
10. History of other diseases causing voiding dysfunction
11. Concomitant Urinary Tract Infection (UTI) (subject can be enrolled followingsuccessful treatment of UTI and a clean urine test), or subjects who have a history ofrecurrent or chronic UTIs (defined as 2 or more UTIs in the past 12 months)
12. Concomitant bladder stones
13. Previous pelvic irradiation or radical pelvic surgery
14. Previous prostate surgery, stent implantations, laser prostatectomy, hyperthermia oranother invasive treatment to the prostate
15. Chronic prostatitis, or recurring prostatitis within the past 12 months
16. Known allergy to nickel
17. Life expectancy less than 24 months
18. Use of concomitant medications (e.g., anticholinergics, antispasmodics or tricyclicantidepressants) affecting bladder function
19. Inability to stop taking anticoagulants and/or antiplatelets for at least 3 days priorto the procedure or coumadin for at least 5 days prior to the procedure (low doseaspirin therapy not prohibited).
20. Taking 5-alpha-reductase inhibitors within 3 months of pre-treatment (baseline)evaluation
21. Taking one of the following within 2 weeks of pre-treatment (baseline) evaluation:
22. alpha-blockers,
23. imipramine,
24. anticholinergics, or
25. cholinergic medication gonadotropin releasing hormonal analogs
26. Taking androgens, unless evidence of eugonadal state for at least 6 months.
27. Taking one of the following within 24 hours of pre-treatment (baseline) evaluation:
28. phenylephrine, or
29. pseudoephedrine
30. Future fertility concerns
31. Any concurrent medical condition or illness that might prevent study completion orwould confound study results