An interventional study of Conventional dual-wavelength diode laser vaporization of the prostate and Ejaculation-preserving dual wavelength diode laser vaporization of the prostate in Benign Prostatic Hyperplasia, Lower Urinary Track Symptoms and Bladder Outlet Obstruction, sponsored by ALI KAMAL M. SAMI. Completed at 1 site in Iraq. Open to male participants aged 50 Years and older. Per ClinicalTrials.gov, last updated 2026-08-20.
Sponsored by ALI KAMAL M. SAMI · Not applicable, Interventional, and Treatment
Surgery to relieve urinary blockage caused by an enlarged prostate works well, but most men lose antegrade ejaculation afterwards, because semen passes backwards into the bladder instead of forwards. For sexually active men this is an important concern and a common reason for delaying or refusing surgery.
This study compared two ways of performing the same operation, laser vaporization of the prostate using a dual-wavelength diode laser. In the conventional technique, prostate tissue is removed from the bladder neck all the way to the verumontanum. In the ejaculation-preserving technique, the surgeon deliberately leaves a 10 mm rim of tissue at the bladder neck untouched, and another 10 mm of tissue just before the verumontanum untouched, while removing the blocking tissue in between. Everything else about the operation, including the laser settings, was the same.
Men were assigned to one of the two techniques by a computer-generated random sequence. They were assessed before surgery and again at 7 to 14 days, 1 month, 3 months, 6 months and 12 months after surgery.
The main question was how many men still had antegrade ejaculation 3 months after surgery. The study also compared urinary symptoms, urine flow rate, residual urine volume, prostate size, erectile function, complications and patient satisfaction, to find out whether preserving ejaculation costs anything in terms of relieving the urinary blockage.
BACKGROUND
Loss of antegrade ejaculation follows conventional transurethral resection or vaporization of the prostate in the majority of men. Two anatomical regions are considered central to this: the internal urethral sphincter at the bladder neck, which prevents retrograde passage of semen, and the paracollicular and supracollicular tissue around the verumontanum, which contributes to the emission phase. Techniques preserving one or both regions have been described across several endoscopic platforms, but evidence specific to the dual-wavelength diode laser is limited and follow-up in previous work has been short.
OBJECTIVE
To determine whether an ejaculation-preserving technique of dual-wavelength diode laser vaporization of the prostate preserves antegrade ejaculation without compromising relief of bladder outlet obstruction, and whether any benefit is durable to 12 months.
DESIGN
Prospective, randomized, single-centre comparative study conducted at the Department of Urology, Royal Hospital, Sulaymaniyah, Kurdistan Region, Iraq. Allocation followed a computer-generated random sequence, with assignments concealed in sequentially numbered opaque sealed envelopes opened after consent. Participants were not informed of their allocation. The operating surgeon was necessarily aware of allocation.
INTERVENTION
All procedures were performed by a single surgeon under spinal or general anaesthesia, using a 22 Fr continuous-flow laser cystoscope sheath with normal saline irrigation. Energy was delivered by a Ceralas dual-wavelength diode laser system (biolitec biomedical technology GmbH, Jena, Germany) emitting simultaneously at 980 nm and 1470 nm, through a bare-tip fibre in continuous-wave mode at a total power of 140 W. Laser wavelength, fibre type, emission mode and power setting were identical in both arms.
Conventional arm: vaporization proceeded from the bladder neck to the verumontanum in the standard fashion, including tissue at the bladder neck and immediately proximal to the verumontanum, until a wide channel was created.
Ejaculation-preserving arm: no vaporization was performed within 10 mm distal to the bladder neck, and no vaporization was performed within 10 mm proximal to the verumontanum. Between these two margins, the lateral lobes, median lobe and anterior tissue were vaporized to the same endpoint as in the conventional arm. Adherence to both margins was recorded prospectively in every case.
ASSESSMENTS
Participants were assessed at baseline and at day 7 to 14, 1 month, 3 months, 6 months and 12 months. Symptoms were quantified with the International Prostate Symptom Score and its quality-of-life item, and erectile function with the five-item International Index of Erectile Function. Uroflowmetry was accepted only with a voided volume of at least 150 mL. Post-void residual volume and prostate volume were measured by transabdominal ultrasound. Ejaculatory status was recorded as a binary patient-reported outcome: presence or absence of any antegrade ejaculate during sexual activity since the preceding visit. Complications were graded using the Clavien-Dindo classification.
ANALYSIS
Continuous variables were compared between arms with the Mann-Whitney U test and within arms against baseline with the Wilcoxon signed-rank test. Proportions were compared with the two-sided Fisher exact test, with risk differences reported using Newcombe hybrid-score 95 percent confidence intervals. No imputation was performed. Analysis was restricted to participants with complete records at every scheduled visit.
NOTE ON REGISTRATION
This trial was registered retrospectively. The protocol, including the primary endpoint, the secondary endpoints and the two 10 mm technical margins, was submitted to and registered by the Scientific Committee of the Department of Clinical Sciences, College of Medicine, University of Sulaimani (number 28, 25 February 2025) and approved by the Ethics Committee of the same institution (number 62, 2 March 2025). Public registry registration was not undertaken before enrolment because the requirement was not appreciated at the time. No outcome measures, eligibility criteria or analysis definitions were altered after the study began.
827 studies on the registry are indexed under Prostatic Hyperplasia; 179 are open to participants now.
This study's enrollment of 119 is above the median of 92 across 626 interventional studies indexed under Prostatic Hyperplasia.
Browse Prostatic Hyperplasia studies →ALI KAMAL M. SAMI is the lead sponsor of 5 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Conventional dual-wavelength diode laser vaporization of the prostate. Vaporization proceeded from the bladder neck to the verumontanum in the standard fashion, with removal of obstructing adenoma including the tissue at the bladder neck and immediately proximal to the verumontanum, until a wide channel was created
Procedure: Conventional dual-wavelength diode laser vaporization of the prostate
Ejaculation-preserving dual-wavelength diode laser vaporization of the prostate. No vaporization was performed within 10 mm distal to the bladder neck, preserving the circular muscle fibres of the internal sphincter, and no vaporization was performed within 10 mm proximal to the verumontanum, preserving the paracollicular and supracollicular tissue. Between these two margins, the lateral lobes, median lobe and anterior tissue were vaporized to the same endpoint as in the conventional arm. Laser settings were identical to the comparator arm.
Procedure: Ejaculation-preserving dual wavelength diode laser vaporization of the prostate
Transurethral vaporization of the prostate using a Ceralas dual-wavelength diode laser (biolitec biomedical technology GmbH, Jena, Germany) emitting simultaneously at 980 nm and 1470 nm, bare-tip fibre, continuous wave, total power 140 W, delivered through a 22 Fr continuous-flow laser cystoscope sheath with normal saline irrigation, under spinal or general anaesthesia. Adenoma was vaporized from the bladder neck to the verumontanum without preservation margins.
Identical equipment, laser settings and anaesthesia to the comparator intervention, with two preservation margins: no vaporization within 10 mm distal to the bladder neck and none within 10 mm proximal to the verumontanum. Adequacy of the mid-prostatic channel was confirmed endoscopically at the end of the procedure. Adherence to both margins was recorded prospectively for every case.
Preservation of antegrade ejaculation
Proportion of participants reporting the presence of any antegrade ejaculate during sexual activity since the preceding visit. Recorded as a binary patient-reported outcome (present or absent). All participants had antegrade ejaculation at baseline as an eligibility requirement.
Time frame: 3 months after surgery
Durability of integrate ejaculation preservation
Proportion of participants reporting presence of any antegrade ejaculate, assessed as for the primary outcome, to test whether any benefit is sustained over time.
Time frame: 6 and 12 months after surgery
Change in international prostate symptom score IPSS
IPSS total score, range 0 to 35, where higher scores indicate more severe lower urinary tract symptoms. Change from baseline is reported.
Time frame: Baseline, 3, 6, and 12 months after surgery
Change in IPSS quality of life score
Single-item IPSS quality-of-life question, range 0 to 6, where higher scores indicate worse bother from urinary symptoms.
Time frame: Baseline, 3, 6, and 12 months after surgery
Change in maximum urinary flow rate (Qmax)
Maximum flow rate in mL/s measured by uroflowmetry, accepted only when voided volume was at least 150 mL. Higher values indicate better flow.
Time frame: Baseline, 3, 6, and 12 months after surgery
Change in post-void residual urine volume
Post-void residual volume in mL measured by transabdominal ultrasound. Lower values indicate more complete bladder emptying.
Time frame: Baseline, 3, 6, and 12 months after surgery
Change in prostate volume
prostate volume in cc measured by transabdominal ultrasound, using the prolate, elipsoid formula with percentage reduction from baseline calculated
Time frame: Baseline, 3, 6, and 12 months after surgery
Change in erectile function (IIEF-5)
Five-item International Index of Erectile Function, range 5 to 25, where higher scores indicate better erectile function. Assessed as a control variable to distinguish ejaculatory from erectile outcomes. Face like, three, six, and 12 months after
Time frame: Baseline, 3, 6, and 12 months after surgery
Complications graded by Clavien-Dindo classification
Clavien-Dindo grade recorded per participant, from grade I (any deviation from normal course) to grade V (death), including in-hospital and all follow-up intervals.
Time frame: From surgery to 12 months after surgery
Patient global satisfaction
Patient-reported global satisfaction with the outcome of surgery on a 5-point scale, where 1 indicates very dissatisfied and 5 indicates very satisfied.
Time frame: 3, 6, and 12 months after surgery
Trifecta outcome
Composite endpoint requiring all three of: IPSS below 8, complete pad independence, and preserved antegrade ejaculation.
Time frame: 12 months after surgery
Operative time, catheterization time and hospital stay
Operative time in minutes measured from insertion to withdrawal of the cystoscope, duration of postoperative catheterisation in hours, and length of hospital stay in hours.
Time frame: Day of surgery to hospital discharge, up to seven days
Early post operative dysuria
Dysuria severity on a visual analogue scale from 0 to 10, where higher scores indicate more severe dysuria, together with the duration of dysuria in days.
Time frame: Day 7 to 14 and 1month after surgery
Re-treatment for benign prostatic obstruction
Proportion of participants requiring any further surgical intervention for benign prostatic obstruction.
Time frame: Up to 12 months after surgery
Plan to share: Yes — De-identified individual participant data underlying the published results, including baseline characteristics, operative details, and all follow-up outcome measurements, will be made available to qualified investigators.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form
Time frame: Beginning 6 months after publication of the primary results and ending 5 years thereafter.
Access criteria: Requests should be directed to the principal investigator and must include a methodologically sound proposal and a stated analysis objective. Data will be released after review of the proposal and completion of a data access agreement.
Ran from Oct 2024 to primary completion in Oct 2025, 12 months.
Of 152 non-industry interventional studies with no phase under Prostatic Hyperplasia, half reached primary completion within 25 months of starting (the median), counting those still running; a quarter within 14 and three quarters within 48. This study's 12 months is below that.
Counting every sponsor, half of 203 studies reached it within 26 months; a quarter within 14 and three quarters within 48.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
ALI KAMAL M. SAMI