An interventional study of High Intensity Focused Ultrasound in Bladder Outlet Obstruction and BPH, sponsored by Icahn School of Medicine at Mount Sinai. Not yet recruiting at 1 site in United States. Open to male participants aged 45 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-10-09.
Sponsored by Icahn School of Medicine at Mount Sinai · Not applicable, Interventional, and Other
Objectives: To assess the efficacy of HIFU therapy for benign prostatic tissue ablation in patients with lower urinary tract symptoms (LUTS) due to bladder outlet obstruction (BOO) that caused by Benign prostatic hyperplasia (BPH).
The primary objective of the study is to determine the efficacy of HIFU therapy by assessing the changes in IPSS score in 6-month post HIFU procedure for BPH with compared to baseline.
The secondary objectives of this study are as follow:
The hypothesis is that a HIFU ablation is a safe and effective treatment for patients with LUTS due to BOO from BPH.
46 studies on the registry are indexed under Urinary Bladder Neck Obstruction; 10 are open to participants now.
This study's planned enrollment of 17 is below the median of 88 across 30 interventional studies indexed under Urinary Bladder Neck Obstruction.
Browse Urinary Bladder Neck Obstruction studies →Icahn School of Medicine at Mount Sinai is the lead sponsor of 776 studies on the registry; 176 are open to participants now.
Of its 125 completed or terminated interventional studies of FDA-regulated products, 83 (66%) have results posted.
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Exclusion Criteria :
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Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
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Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
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Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
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Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
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Immunosuppression
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Corticosteroids (steroids)
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Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
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Clinically significant
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Investigational drug or device
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It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
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HIFU therapy for benign prostatic tissue ablation in patients with lower urinary tract symptoms (LUTS) due to bladder outlet obstruction
Device: High Intensity Focused Ultrasound
High Intensity Focused Ultrasound (HIFU) works with an image-guided transrectal probe that utilizes 3-10 MHz ultrasound waves at very high powers (200W). These waves can be very precisely directed at target tissue. Through both thermal and mechanical forces (shearing motion and mechanical energy leading to hyperthermia) the focal point core temperature can be raised significantly (\> 80°C) leading to coagulative necrosis to the target tissue while sparing surrounding tissue. The degree of tissue injury is based on the temperature and the duration of exposure, with the cooling off time allowing for the heat to dissipate to prevent the damage to surrounding tissues. The most common device involves a transrectal transducer with ultrasound guidance that can be performed under either general or spinal anesthesia. The device has been FDA approved to be used in ablation of prostatic tissue since 2018.
Also known as: HIFU
Change in The International Prostate Symptom Score (I-PSS)
The International Prostate Symptom Score (I-PSS) is designed to assess severity of symptoms in benign prostatic hypertrophy. It is based on the answers to seven questions concerning urinary symptoms and one question concerning quality of life. Each question concerning urinary symptoms allows the patient to choose one out of six answers indicating increasing severity of the particular symptom. The answers are assigned points from 0 to 5. The total score can therefore range from 0 to 35 with higher score indicating more symptomatic. It classifies patients' symptomatology as follows: Mild (symptom score ≤ 7), Moderate (score 8-19), and Severe (score 20-35).
Time frame: baseline and 6 months post-treatment
Frequency and proportions of adverse events and all cause hospitalization
Adverse events, probably, or possibly related to the device or surgical procedure, including any all-cause hospitalization within 30 days post-op. Frequencies and proportions of adverse events will be reported in patients likely and unlikely related to the device or surgical procedure.
Time frame: within the first 30 days after the HIFU intervention
Operation time
Operation time: Amount of time required from the start to the end of the HIFU procedure, the total operation time
Time frame: approximately 45-120 minutes
Ablation time
Ablation time: Amount of time required for HIFU to ablate the benign prostatic tissue. Defined as the time from the first HIFU firing until the time of the last HIFU firing.
Time frame: average 15-45 minutes
Catheterization times
Catheterization times: Number of days required for foley catheter after the procedure.
Time frame: 1 week post-procedure, or until the patient passes the trial of void
Categorical Ablation Zones (Peripheral, Transitional, or Central Prostate Zones)
Categorical ablation zones: Defined as the prostate area involved in HIFU ablation, including the peripheral, transitional, or central zone. This outcome will be recorded as a categorical variable based on the anatomical region(s) of the prostate targeted by the ablation.
Time frame: During procedure
Male-Genitourinary Pain Index (M-GUPI) pain questionnaire
Patient's post-op pain level will be assessed using the M-GUPI pain questionnaire: a pain questionnaire to assess their postoperative pain. Total score of the M-GUPI will be analyzed along with patients' use of opioid pain medication to assess patient pain levels at discharge after HIFU procedure. The M-GUPI questionnaire has 10 pain items (total pain subscale score 0-23), 2 urinary symptom items (total urinary subscale score 0-10), and 3 QOL items (total QOL subscale score 0-12). As with the NIH-CPSI, the scores from each item are summed for a total score that ranges from 0 to 45, higher scores indicate greater severity.
Time frame: at discharge after HIFU procedure (expected time: Post-op Day 1), 1-week and 1-month post-op
Changes in IPSS scores
Symptoms and urinary flow improvement are assessed through changes in IPSS scores: Difference in IPSS scores at 1 month, 3 months, and 12 months post-treatment compared to pre-op baseline. IPSS score is a standardized questionnaire for assessing urinary flow. The total score can range from 0 to 35 (asymptomatic to very symptomatic). It classifies patients' symptomatology as follows: Mild (symptom score ≤ 7), Moderate (score 8-19), and Severe (score 20-35).
Time frame: Baseline, 1-, 3-, 12- months post-treatment
Changes in maximum flow rate (Qmax)
Symptoms and urinary flow improvement are assessed through changes in Qmax . Qmax is the maximum flow rate of urine, measured in milliliters per second (ml/s). A Qmax value below 15 ml/s may suggest urinary issues
Time frame: Baseline, 1-, 3-, 6-, 12- months post-treatment
Changes in Post-Void Residual (PVR)
Symptoms and urinary flow improvement are assessed through changes in PVR. PVR is the amount of urine left in the bladder after urination.
Time frame: Baseline, 1-, 3-, 6-, 12- months post-treatment
Changes in the type of BPH medications
Effectiveness of HIFU is assessed through changes in the type of BPH medications and proportions of patients who are taking BPH medications following treatment compared to pre-op baseline BPH medications at discharge after HIFU procedure, 1 week, 1-, 3-, 6-, and 12- month post op follow up. Types of BPH medications include Flomax, Uroxatral, Cardura, Rapaflo, Hytrin, Proscar, Propecia, Avodart.
Time frame: Baseline, 1 week, 1-, 3-, 6-, and 12- month post-treatment
Change in Prostate Specific Antigen (PSA) level.
Effectiveness of HIFU is assessed through change from pre-op baseline PSA to PSA at 6-month and 12-month post op. Prostate-specific antigen (PSA) is a protein produced by prostate cells. The PSA test is done to help screen for and monitor prostate cancer in men.
Time frame: Baseline, 6-, and 12- month post-treatment
Change in Prostate measurement
Effectiveness of HIFU is assessed through change from pre-op baseline prostate measurement to 6- to 12- month post-op. Pre-op baseline measurement will be defined as within 1 year prior to the HIFU BPH procedure. This will be performed through transrectal ultrasound or MRI scan to measure the size of prostate gland and assess the calcification level of prostate. If patients have both imaging results, MRI values will be favored for more accurate assessment. Post operative imaging will be assessed in between 6 to 12 months post-op and compared with the pre-op baseline imaging result. Differences of the prostate size and calcification level between 6-12 months post-op versus pre-op baseline will be collected.
Time frame: Baseline, 6-, and 12- month post-treatment
Number of BPH procedures
Effectiveness of HIFU is assessed through re-operation rate at 12 months: number of BPH procedures that patient required after the HIFU procedure.
Time frame: 12- month post-treatment
Change in the International Index of Erectile Function (IIEF) questionnaire
Difference in erectile or ejaculation dysfunction in patients who are sexually active in baseline pre-op: Difference in IIEF score at 3-months post-op minus pre-op baseline and at 6-month post-op minus pre-op baseline. The International Index of Erectile Function is a validated questionnaire used to assess patients' erectile function and is standard of care to assess prior to and following BOO treatment to measure treatment success and complications. Erectile dysfunction severity is classified as follows based on the score: 1-10 indicates severe dysfunction; 11-16, moderate dysfunction; 17-21, mild to moderate dysfunction; 22-25, mild dysfunction; and 26-30, no dysfunction. Total score ranges from 15-75, total score indicates better health outcomes.
Time frame: Baseline, 3- and 6- months post treatment
Change in the Male Sexual Health Questionnaire- Ejaculatory Dysfunction (MSHQ-EjD)
Difference in erectile or ejaculation dysfunction in patients who are sexually active in baseline pre-op: Difference in MSHQ-EjD scores at 3-months post-op minus baseline and at 6-month post-op minus pre-op baseline. The Male Sexual Health Questionnaire- Ejaculatory Dysfunction is a validated questionnaire used to assess patients' ejaculatory function and is standard of care to assess prior to and following BOO treatment to measure treatment success and complications. Scores range from 0 to 20, higher scores indicate better health outcomes. Scores below 8 suggest potential ejaculatory dysfunction, including premature or delayed ejaculation. Scores between 9 and 12 indicate moderate concerns that may not meet clinical criteria for dysfunction. Scores above 12 generally reflect normal ejaculatory function with minimal concerns.
Time frame: Baseline, 3- and 6- months post treatment
Plan to share: Yes — Individual participant data that underlie the results reported in this article, after deidentification (text, tables, figures, and appendices).
Supporting information: Study protocol
Time frame: Immediately following publication. No end date.
Access criteria: Researchers who provide a methodologically sound proposal. For individual participant data meta-analysis. Proposals may be submitted up to 36 months following article publication. After 36 months the data will be available in our University's data warehouse but without investigator support other than deposited metadata. Information regarding submitting proposals and accessing data may be found at (Link tbd).
No publications or documents are linked to this record.
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