Optical Internal Urethrotomy (OTU / DVIU) — Cost, Top Hospitals & Success Rates | MyMedicPlus

Optical internal urethrotomy (OTU), also termed direct vision internal urethrotomy (DVIU) or the Sachse urethrotomy after its populariser, is an endoscopic procedure for the treatment of urethral stricture disease — the pathological narrowing of the urethra resulting from spongiofibrosis (scarring within the spongy erectile tissue, the corpus spongiosum, that surrounds the urethral lumen). Stricture disease impairs urinary flow, causes obstructive lower urinary tract symptoms (LUTS), and predisposes to urinary tract infections, bladder dysfunction, and upper tract damage if longstanding.

The fundamental principle of OTU/DVIU is to incise the cicatricial scar tissue under direct endoscopic vision, thereby widening the urethral lumen and restoring adequate urinary flow. Unlike blind urethral dilation (which stretches and re-tears the stricture) or urethral bouginage (which compresses and traumatises the spongiosum further), DVIU incises the fibrotic tissue sharply under vision, theoretically allowing a clean healing plane.

The procedure was first systematically described by Sachse in 1974 using a rigid urethrotome fitted with a cold (unheated) knife blade. The surgeon introduces the instrument under direct optical vision — using the rigid urethroscope to visualise the stricture — and makes a precise incision through the narrowed segment, typically at the 12 o'clock position (superior). Multiple incisions at 12, 5, and 7 o'clock positions are used for dense or fibrous strictures. Following incision, a urethral catheter is left in situ for 24–72 hours to allow initial healing before voiding trials begin.

Modern modifications include laser energy delivery (holmium:YAG or thulium fibre laser) through a flexible or rigid urethroscope, which may offer advantages in haemostasis and precision for certain stricture types. The TURNS (Trial of Urethral Resection in Normal Strictures) and subsequent randomised evidence have clarified the substantial limitations of DVIU as a durable treatment, particularly for recurrent or longer strictures, prompting a shift in urological practice toward earlier referral for urethroplasty in appropriate patients.

Understanding stricture aetiology, anatomy, and density is essential for selecting the appropriate treatment and predicting outcomes after DVIU.

Anatomical location (determines prognosis after DVIU):

• Bulbar urethra — the most common site for idiopathic and post-inflammatory strictures. Bulbar strictures represent the most favourable location for DVIU, with the best single-procedure success rates. Short (<1.5 cm) single-site bulbar strictures in the proximal bulb are the classic ideal candidate for DVIU.
• Penile urethra — strictures here most commonly follow lichen sclerosus (BXO), instrumentation, or hypospadias repair failure. DVIU outcomes are significantly poorer in penile strictures; urethroplasty is strongly preferred as primary treatment.
• Membranous and posterior urethra — pelvic fracture urethral injury (PFUI) and post-prostatectomy anastomotic strictures. These require specialised surgical expertise; DVIU has a limited role and urethroplasty (perineal approach) is the definitive treatment for PFUI.

Stricture aetiology:

• Idiopathic / inflammatory: Most common cause overall; many are likely related to subclinical gonorrhoea or other urethritis. Typically located in the bulbar urethra, amenable to DVIU for primary short strictures.
• Iatrogenic (instrumentation-related): Urethral catheterisation, cystoscopy, TURP, brachytherapy. Location depends on the procedure; outcomes variable.
• Lichen sclerosus (BXO): Progressive inflammatory dermatosis causing pan-urethral fibrosis, typically extending from the meatus proximally. DVIU is not appropriate — the disease progresses regardless, and urethroplasty with non-genital grafting (buccal mucosa) is the standard.
• Traumatic: Straddle injuries to the perineum cause bulbar strictures; pelvic fracture causes posterior urethral distraction defects. DVIU for bulbar trauma strictures can be appropriate as a first-line approach if short; posterior injuries require urethroplasty.

Stricture characteristics affecting DVIU candidacy:

• Length: Strictures <1.5 cm (ideally <1 cm) have the best DVIU outcomes. Success rates decline sharply for strictures >2 cm.
• Density/spongiofibrosis: Superficial (partial-depth) spongiofibrosis produces soft, pliable strictures that respond better to DVIU than deep, dense spongiofibrosis.
• Number: Single strictures do better than multiple or complex strictures.
• Prior treatment: Prior DVIU significantly reduces the probability of success with repeat DVIU.

Proper patient selection is the most important determinant of DVIU success. The ideal candidate for OTU/DVIU has a specific, well-defined profile that must be carefully assessed before offering the procedure as primary treatment.

Ideal DVIU candidates:

• Primary (first-time, never treated) urethral stricture
• Stricture located in the bulbar urethra
• Stricture length <1.5 cm (short segment)
• Superficial spongiofibrosis on ultrasound or MRI assessment
• Non-lichen sclerosus aetiology
• Patient who understands the high recurrence rate and is committed to follow-up and possibly clean intermittent catheterisation (CIC)

Poor DVIU candidates (urethroplasty preferred):

• Previous failed DVIU — recurrence rates after repeat DVIU fall to approximately 12% at 5 years (TURNS trial data)
• Penile urethral location
• Lichen sclerosus (BXO)-associated stricture
• Stricture length >2 cm
• Dense spongiofibrosis on imaging
• Pelvic fracture urethral injury
• Fistula or periurethral abscess associated with the stricture

Pre-operative evaluation:

• Uroflowmetry: Objective assessment of peak flow rate (Qmax). Stricture disease typically produces a plateau-shaped flow curve with Qmax <10 mL/s. Post-void residual (PVR) measurement by bladder scan quantifies bladder emptying efficiency.
• Retrograde urethrogram (RUG) and voiding cystourethrogram (VCUG): Fluoroscopic imaging defines stricture location, length, and number. The combination of RUG (filling from below) and VCUG (filling from above) maps the entire stricture length accurately.
• Urethral ultrasound: Increasingly used to assess the depth of spongiofibrosis — a key predictor of DVIU success and guide to surgical planning.
• Cystoscopy / flexible urethroscopy: Direct visualisation confirms stricture location and allows assessment of calibre, multiplicity, and mucosal appearance. Performed immediately before DVIU in the same sitting or as a diagnostic-only prior assessment.
• Urine culture: Active urinary infection must be treated before any endoscopic urethral procedure to minimise bacteraemia and sepsis risk.

OTU/DVIU is performed under cystoscopic guidance with the patient in the lithotomy position. The key technical decisions are the energy source used to incise the stricture, the approach (rigid vs semi-rigid urethrotome), and the number and location of incisions made.

Cold Knife (Sachse) Urethrotomy

The Sachse optical urethrotome is a rigid instrument housing a 0-degree or 12-degree lens alongside a retractable cold knife blade on a rail mechanism. The urethrotome is introduced transurethrally under direct vision to the point of the stricture. The blade is deployed through the scar at the 12 o'clock position under direct optical visualisation until healthy, bleeding, unscarred tissue is reached proximal to the stricture. Additional incisions at the 5 and 7 o'clock positions are made for dense or circumferential strictures. Cold knife urethrotomy is the historical and most widely practiced technique, with the largest body of long-term outcome data.

Laser Internal Urethrotomy

Laser energy has been adopted to incise urethral strictures, offering potential advantages including improved haemostasis, precise depth control, and the ability to use flexible urethroscopes in settings where rigid instrumentation is challenging.

• Holmium:YAG laser (Ho:YAG): A 365 or 550 micrometre fibre is passed through the working channel of a rigid or flexible urethroscope. The holmium laser ablates and cuts through fibrotic tissue with minimal thermal spread (approximately 0.5 mm penetration depth). Multiple comparative studies show equivalent stricture-free rates between Ho:YAG laser and cold knife DVIU, with slightly better haemostasis for laser.
• Thulium fibre laser (TFL): A newer platform operating at 1,940 nm with continuous-wave emission, offering superior cutting precision, excellent haemostasis, and compatibility with flexible urethroscopes. Emerging evidence suggests comparable or potentially superior outcomes to Ho:YAG, particularly for complex or denser strictures, though long-term comparative data are still accumulating.

Post-incision catheter management: A 16–18 Fr urethral catheter is left in situ for 24–72 hours following the incision to provide a scaffold for initial healing, achieve haemostasis, and maintain urethral patency. Longer catheterisation periods (5–7 days) have been used historically but do not appear to improve long-term outcomes in randomised comparisons. Antibiotic prophylaxis covering urinary tract pathogens (typically a fluoroquinolone or trimethoprim) is administered peri-operatively and continued while the catheter remains in place.

Clean Intermittent Catheterisation (CIC) After DVIU

A self-catheterisation regimen using a 14–16 Fr catheter is increasingly prescribed after DVIU to maintain urethral patency during healing and reduce stricture recurrence. Typical regimens reduce gradually from daily to three times weekly to once weekly over 6–12 months. While CIC has not been conclusively proven to reduce long-term recurrence rates in randomised trials, it provides reliable objective monitoring and patient empowerment, and many urologists incorporate it as standard management in high-recurrence-risk cases.

DVIU/OTU offers several genuine advantages as an initial treatment for selected urethral strictures, while clinicians and patients must maintain realistic expectations about long-term durability based on the best available evidence.

Immediate and short-term benefits:

• Rapid improvement in urinary flow: peak flow rate (Qmax) typically increases from a pre-treatment average of 7–9 mL/s to 15–20 mL/s immediately post-procedure. A target Qmax above 15 mL/s with a normal-shaped uroflow curve indicates successful urethral widening.
• Rapid symptomatic relief: voiding difficulty, urinary straining, poor stream, sensation of incomplete bladder emptying, and post-void dribbling resolve promptly in the majority of patients after successful DVIU.
• Minimally invasive: performed endoscopically without skin incisions, typically as a day case under general, spinal, or even local anaesthesia with sedation. Hospital stay is usually 0–1 nights.
• No compromise of future urethroplasty: an appropriately performed DVIU does not impair the success of subsequent definitive urethroplasty, allowing a staged approach where DVIU buys time in patients not yet fit for open surgery.

Long-term success rates — TURNS trial and contemporary evidence:

The TURNS (Trauma and Urologic Reconstructive Network of Surgeons) multicentre trial, the most robust prospective evidence base for DVIU outcomes, demonstrated:

• Primary (first-time) DVIU for bulbar stricture: approximately 54–58% stricture-free at 2 years, declining to approximately 50% at 5 years for short strictures (<2 cm) in ideal candidates.
• Repeated DVIU after one prior failure: approximately 25–35% stricture-free at 2 years, declining to approximately 12% at 5 years — highlighting the dramatic reduction in durability with repeated endoscopic procedures.
• Optimal DVIU candidates (short, single bulbar stricture, primary): up to 60% long-term success.
• Poor DVIU candidates (penile, long, recurrent, dense): success rates below 20% at 5 years.

These data inform current EAU and AUA guideline recommendations that urethroplasty is the preferred definitive treatment for recurrent, long, or penile strictures, and that DVIU should primarily be offered as a first-line approach for primary short bulbar strictures in appropriate surgical candidates.

OTU/DVIU is generally well tolerated with a low rate of serious complications. Understanding the risk profile allows informed patient decision-making and appropriate post-procedure monitoring.

Peri-operative complications:

• Haemorrhage: Minor bleeding from the incision is common and self-limiting. Significant haemorrhage requiring transfusion or endoscopic haemostasis is rare (<1%). Laser techniques, particularly TFL, tend to produce less bleeding than cold knife.
• Urinary tract infection and urosepsis: UTI occurs in 5–15% of patients post-DVIU, particularly in those with pre-existing bacteriuria that was not adequately treated pre-operatively. Urosepsis is rare but potentially life-threatening; prophylactic antibiotics and pre-operative urine sterilisation are essential.
• Urethral perforation / false passage: Inadvertent perforation into periurethral tissues during incision can occur, particularly with dense fibrous strictures where the lumen is difficult to identify. Usually managed conservatively with catheterisation.
• Extravasation: Irrigation fluid extravasation into periurethral tissues during the procedure is usually minor and self-limiting but rarely causes significant periurethral haematoma.

Long-term complications:

• Stricture recurrence: The most important adverse outcome. Recurrence rates are high — approximately 40–50% within 2 years for primary DVIU, rising to over 80–85% at 5 years after repeated DVIU. Recurrence requires either repeat DVIU (with further reduced success) or escalation to urethroplasty.
• Erectile dysfunction: A genuine concern often cited by patients, though well-conducted studies suggest DVIU itself carries a low risk of de novo erectile dysfunction. Retrograde ejaculation can occur transiently. Conversely, untreated obstructive stricture disease itself impairs sexual function over time.
• Urinary incontinence: Stress incontinence is rare after bulbar DVIU; risk is higher for membranous urethral procedures where the external sphincter may be inadvertently damaged.
• Worsening spongiofibrosis: Repeated endoscopic incision and catheterisation cycles can worsen the underlying spongiofibrosis, potentially making subsequent urethroplasty more complex. This is a key argument for offering urethroplasty earlier rather than performing repeated DVIU procedures.

Contraindications to DVIU include active untreated urinary infection, inability to pass the urethrotome to the stricture (very tight or complex stricture), and penile or complex pan-urethral stricture disease where urethroplasty is clearly superior.

Post-DVIU follow-up is essential for early detection of stricture recurrence, which remains the primary limitation of the procedure. A structured surveillance protocol is the standard of care.

Immediate post-operative period:

• The urethral catheter (16–18 Fr) is removed at 24–72 hours post-procedure, or at 5–7 days if the stricture was particularly dense or a larger incision was required. Voiding trial at catheter removal confirms adequate flow.
• Antibiotic cover is maintained while the catheter is in situ (typically trimethoprim 200 mg once daily or a fluoroquinolone).
• Mild urethral burning and haematuria on voiding are expected for 5–10 days following catheter removal. Patients should be advised to maintain adequate oral hydration.
• Strenuous physical activity and sexual intercourse should be avoided for 2–4 weeks following the procedure.

Clean intermittent catheterisation (CIC) protocol: In centres adopting CIC post-DVIU, the patient is taught self-catheterisation with a 14–16 Fr catheter before discharge. A reducing frequency regimen is commonly used: daily for the first month, every other day for month 2, three times weekly for months 3–4, twice weekly for months 5–6, and weekly for months 6–12. Uroflowmetry is checked if flow deteriorates during the CIC programme.

Surveillance uroflowmetry schedule: Objective uroflowmetry at 3, 6, and 12 months after DVIU, then annually for at least 5 years, is the minimum recommended follow-up. Any decline in Qmax below 12–15 mL/s or re-emergence of obstructive LUTS should prompt cystoscopy or urethrogram to confirm recurrence.

Criteria for definitive urethroplasty referral: Recurrence after a single DVIU (particularly within 12 months), any recurrence after a second DVIU, penile stricture, stricture length progression, or identification of lichen sclerosus on urethroscopic biopsy should prompt timely referral to a urethral reconstruction specialist for urethroplasty planning.

OTU/DVIU is substantially less expensive than urethroplasty (open urethral reconstruction) for the initial procedure, which partly explains its continued widespread use despite lower long-term success rates. However, the high recurrence rate and need for repeated procedures means the cumulative long-term cost of repeated DVIU may approach or exceed the one-time cost of definitive urethroplasty.

Key cost-influencing factors:

• Anaesthetic approach: General or spinal anaesthesia adds anaesthetic team fees; local anaesthesia with sedation (in office urethrotomy settings) reduces costs significantly.
• Energy source: Laser systems (holmium or thulium) carry higher capital equipment costs than cold knife instruments; this is reflected in facility fees at laser-equipped centres.
• Inpatient versus day surgery: Most uncomplicated DVIU procedures are performed as day cases. Overnight admission adds facility and nursing costs.
• CIC consumables: If a CIC programme is adopted post-procedure, the ongoing catheter and lubricant supply costs should be factored into total management costs over 6–12 months.
• Follow-up surveillance: Uroflowmetry visits, urethrogram imaging, and repeat cystoscopy for recurrence assessment contribute to long-term management costs.
• Cumulative cost of recurrence: Each recurrence requiring repeat DVIU adds procedure costs. After two failed DVIU attempts, the cumulative endoscopic cost often exceeds the one-time cost of urethroplasty, favouring the definitive reconstructive option on both clinical and economic grounds.

International cost comparisons: DVIU costs in the USA range from USD 3,000–8,000 depending on facility and anaesthesia. In India, Thailand, or Turkey at JCI-accredited centres, equivalent procedures can be performed for 30–60% less with equivalent technical standards. Urethroplasty abroad at experienced urethral reconstruction centres is also available at significant savings compared to UK and USA prices.

Several alternative treatments exist for urethral stricture disease across the spectrum of severity and complexity. DVIU occupies a specific niche — primarily short, primary, bulbar strictures — and other approaches are preferred or superior for most other presentations.

Urethral dilation: Sequential passage of dilating bougies or balloon catheters to stretch the stricture. Historically the first-line treatment, dilation is now recognised as inferior to DVIU in terms of durability and tissue handling. It is largely reserved for patients who are not candidates for surgery or who manage their own dilation programme at home. Repeated dilation worsens spongiofibrosis and complicates future reconstruction.

Clean intermittent catheterisation (CIC) alone: For patients who are medically unfit for any surgical intervention, self-catheterisation at regular intervals maintains urethral patency and prevents acute urinary retention without directly treating the underlying fibrosis. CIC is a management strategy, not a cure.

Urethroplasty (open urethral reconstruction) — the gold standard for most strictures: Urethroplasty achieves 5-year stricture-free rates of 80–95% depending on stricture location, length, and technique used — dramatically superior to DVIU for recurrent, long, or penile strictures. Techniques include:

• Excision and primary anastomosis (EPA): For short bulbar strictures (<2 cm), the scarred segment is excised and healthy urethral ends are sutured together. 5-year success rates of 90–95%.
• Buccal mucosal graft urethroplasty (BMG): For longer bulbar or penile strictures, a graft of mucosa harvested from the inner cheek is inlaid (dorsal, ventral, or lateral) or tubed to reconstruct the urethral lumen. 5-year success rates of 80–90%.
• Staged urethroplasty: For complex pan-urethral, hypospadias-related, or radiation-damaged strictures.

Permanent urethral stents: Urolume endoprosthesis and similar permanent stents have been largely abandoned due to poor long-term outcomes (epithelial ingrowth, difficult removal) and are no longer recommended for routine stricture management.

Suprapubic catheterisation: Emergency decompression for acute retention in patients not immediately suitable for definitive repair. Permits elective planning of the definitive procedure without the pressure of acute retention.