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): 50.0-85.0,  Prostatic Hyperplasia, Benign Enlarged Prostate With Lower Urinary Tract Symptoms Prostate volume between 40 and 300 cm3 2. Diagnosis of BPH with moderate to severe lower urinary tract symptoms (LUTS) defined as at least one of the following a. IPSS greater than 18 b. IPSS Quality of Life (QoL) assessment greater than 3 c. Qmax less than 12 mL/sec 3. Refractory or intolerant to medical management 4. Ineligibility for or refusal of surgical management 5. One of the following a. Baseline prostate specific antigen (PSA) ≤2.5 ng/mL b. Baseline PSA >2.5 ng/mL and ≤10 ng/mL AND free PSA ≥25% of total PSA c. Baseline PSA >2.5 ng/mL and ≤10 ng/mL AND free PSA <25% of total PSA AND negative 12 core prostate biopsy in the past 12 months d. Baseline PSA >10 ng/mL AND negative 12 core biopsy within the past 12 months  History of prostate, bladder or rectal malignancy. Biopsy proven urethral cancer. 2. History of rectal disease 3. Neurogenic bladder disorder due to multiple sclerosis, Parkinson's disease, spinal cord injury, diabetes, etc., as demonstrated on urodynamic testing. 4. Detrusor muscle failure, urethral stenosis, or urinary obstruction due to causes other than BPH, as demonstrated on urodynamic testing 5. Bladder diverticula greater than 5 cm or bladder stones greater than 2 cm 6. Cystolithiasis within the past three months 7. Baseline serum creatinine greater than 1.8 8. Evidence of tortuous or atherosclerotic blood vessels 9. Presence of collateral vessel pathways potentially endangering normal territories during embolization that cannot be bypassed with the microcatheter 10. Active urinary tract infection, interstitial cystitis, or prostatitis within the last 5 years 11. Coagulation disturbances not normalized by medical treatment 12. Allergy to iodinated contrast agents not responsive to steroid premedication regimen 13. Previous radical pelvic or rectal surgery, or pelvic irradiation 14. Prior surgical prostate intervention 15. Treatment with beta-blocker, antihistamine, anticonvulsant, or antispasmodic medication within 1 week of treatment there has been a stable voiding pattern while medicated with the drug(s) for 6 months 16. Use of prostate active medications, including alpha blockers, anti-cholinergics, androgens, anti-androgens, gonadotropins-releasing hormonal analogs, PDE5-inhibitors, 5-alpha reductase inhibitors within 2 months of intervention, unless the medication is necessary to avoid symptom exacerbation and disability, in this case medication should not be initiated or dose adjusted within 1 month of study enrollment and dose should not be adjusted during the study period 17. Interest in future fertility 18. Mental condition or disorder that interferes with participants' ability to provide written informed consent 19. Current severe or uncontrolled disease (metabolic, hematologic, renal, hepatic, pulmonary, neurologic, cardiac, infectious or gastrointestinal) that in the Investigator's judgment makes the patient unsuitable for trial due to increased risk of complications 20. Known immunosuppression 21. Life expectancy less than 6 months