86. Urethral Stricture Disease скачать в хорошем качестве

86. Urethral Stricture Disease

86. Urethral Stricture Disease Q. 1. What is urethral stricture disease, and how is it defined? Ans. Urethral stricture disease refers to a fixed anatomical narrowing of the urethra caused by scarring, which prevents instruments from passing without damaging the urethral mucosal lining. This scarring process often involves the underlying spongy erectile tissue of the corpus spongiosum (spongiofibrosis), which, through contraction, reduces the urethral lumen. The term "stricture" is specifically limited to conditions affecting the anterior urethra. Narrowings in the posterior urethra, such as those resulting from trauma or radical prostatectomy, are more accurately termed posterior urethral injury (PUI), posterior urethral stenosis, or urethral contractures/stenosis, distinguishing them from the anterior urethral strictures. Q. 2. What are the non-surgical treatment options for urethral strictures? Ans: Non-surgical treatments primarily aim to widen the urethral lumen, but their long-term success rates are generally lower than open reconstruction. 1. Dilation: The oldest and simplest treatment, involving stretching the scar without tearing it. It may be curative for epithelial strictures without spongiofibrosis. Soft techniques over multiple sessions are favored, with urethral balloon-dilating catheters being the safest method. 2. Internal Urethrotomy: Involves incising the stricture transurethrally to allow the lumen to enlarge. Success depends on proper wound healing (epithelialization vs. scar contraction). It is most effective for short (less than 1.5 cm) bulbar urethral strictures not associated with dense spongiofibrosis. Multiple incisions or deep cuts can carry risks such as erectile dysfunction. Its curative success rate is low (20-35%), and repeated attempts are generally not more successful and may diminish the success of subsequent open reconstruction. 3. Drug-coated Balloons (e.g., Optilume): A newer technology, approved in 2023, that eludes paclitaxel to inhibit fibroblast growth and scar formation, aiming to reduce stricture recurrence. Initial studies show promising results, but its role as an initial vs. salvage treatment and its cost-effectiveness are still being evaluated. 4. Self-catheterization: Used after internal urethrotomy to maintain lumen patency. While anecdotally reported to improve cure rates, strictures often recur once self-obturation stops. 5. Pharmacological Agents: Colchicine and Mitomycin C have been explored to inhibit wound contraction and fibrosis, potentially improving urethrotomy results. 6. Lasers: Laser urethrotomy results are mixed and have not demonstrated superiority over cold-knife urethrotomy. 7. Urethral Stents: Removable or permanently implantable stents are designed to oppose wound contraction. However, long-term effectiveness is debated, and some permanent stents, like the UroLume, are no longer on the market. Q.3. What are posterior urethral injuries (PUIs) and how do they differ from anterior urethral strictures? Ans: Posterior urethral injuries (PUIs) are severe disruptions of the membranous urethra, typically resulting from blunt pelvic trauma, such as pelvic fractures. They are distinct from anterior urethral strictures in several key ways: 1. Location: PUIs involve the posterior urethra, specifically the membranous urethra, which is surrounded by the pelvic floor musculature. Anterior strictures involve the penile or bulbous urethra, surrounded by the corpus spongiosum. 2.Cause: PUIs are primarily traumatic distraction defects, often caused by the shearing force of a pelvic fracture pulling the prostate (like an "apple") off the membranous urethra (the "stem"). Other posterior urethral narrowings, like those after radical prostatectomy, are termed contractures or stenoses, not strictures, according to international consensus. 3.Nature of Injury: PUIs are often obliterative or near-obliterative defects with extensive fibrosis between the distracted urethral ends. While anterior strictures involve a scarring process that narrows the lumen, PUIs involve a complete or near-complete discontinuity of the urethra.