Urethral stricture | |
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Other names | Urethral narrowing, urethral stricture disease |
Urethra is tube at center. | |
Specialty | Urology |
A urethral stricture is a narrowing of the urethra, the tube connected to the bladder that allows urination. The narrowing reduces the flow of urine and makes it more difficult or even painful to empty the bladder. [1]
Urethral stricture is caused by injury, instrumentation, infection, and certain non-infectious forms of urethritis. The condition is more common in men due to their longer urethra. [1]
The hallmark sign of urethral stricture is a weak urinary stream. Other symptoms include: [2]
Some people with severe urethral strictures are completely unable to urinate. This is referred to as acute urinary retention, and is a medical emergency. Hydronephrosis and kidney failure may also occur. [3] [4]
Urethral strictures most commonly result from injury, urethral instrumentation, infection, non-infectious inflammatory conditions of the urethra, and after prior hypospadias surgery. Less common causes include congenital urethral strictures and those resulting from malignancy. [2]
Urethral strictures after blunt trauma can generally be divided into two sub-types;
Other specific causes of urethral stricture include:
Among ways to diagnose this condition is:
Initial treatment usually involves urethral dilation (widening the tube) or urethrotomy, where the stricture is cut away with a cystoscope.
Urethral dilation and other endoscopic approaches such as direct vision internal urethrotomy (DVIU), laser urethrotomy, and self intermittent dilation are the most commonly used treatments for urethral stricture. However, these approaches are associated with low success rates [11] and may worsen the stricture, making future attempts to surgically repair the urethra more difficult. [12]
A Cochrane review found that performing intermittent self-dilatation may confer a reduced risk of recurrent urethral stricture after endoscopic treatment, but the evidence is weak. [13]
Urethroplasty refers to any open reconstruction of the urethra. Success rates range from 85% to 95% and depend on a variety of clinical factors, such as stricture as the cause, length, location, and caliber. [14] [15] [16] [17] Urethroplasty can be performed safely on men of all ages. [18]
In the posterior urethra, anastomotic urethroplasty (with or without preservation of bulbar arteries) is typically performed after removing scar tissue.[ citation needed ]
In the bulbar urethra, [14] [15] [16] the most common types of urethroplasty are anastomotic (with or without preservation of corpus spongiosum and bulbar arteries) and substitution with buccal mucosa graft, full-thickness skin graft, or split thickness skin graft. These are nearly always done in a single setting (or stage).[ citation needed ]
In the penile urethra, anastomotic urethroplasties are rare because they can lead to chordee (penile curvature due to a shortened urethra). Instead, most penile urethroplasties are substitution procedures utilizing buccal mucosa graft, full-thickness skin graft, or split-thickness skin graft. These can be done in one or more settings, depending on stricture location, severity, cause and patient or surgeon preference.
A permanent urethral stent [19] was approved for use in men with bulbar urethral strictures in 1996, but was recently[ when? ] removed from the market.[ citation needed ]
A temporary thermoexpandable urethral stent (Memotherm) is available in Europe but is not currently approved for use in the United States.
When in acute urinary retention, treatment of the urethral stricture or diversion is an emergency. Options include:
Following urethroplasty, patients should be monitored for a minimum of 1 year, since the vast majority of recurrences occur within 1 year.
Because of the high rate of recurrence following dilation and other endoscopic approaches, the provider must maintain a high index of suspicion for recurrence when the patient presents with obstructive voiding symptoms or urinary tract infection.
Comparing the two surgical procedures, a UK trial found that both urethrotomy and urethroplasty are effective in treating urethral narrowing in the bulbar region. At the same time the more invasive urethroplasty had longer-lasting benefit and was associated with fewer re-interventions. [20] [21] The results were integrated into the new UK guidelines on the treatment urethral narrowing by British Association of Urological Surgeons. [22]
The use of bioengineered urethral tissue is promising, but still in the early stages. The Wake Forest Institute of Regenerative Medicine has pioneered the first bioengineered human urethra and in 2006 implanted urethral tissue grown on bioabsorbable scaffolding (approximating the size and shape of the affected areas) in five young (human) males who had congenital defects, physical trauma, or an unspecified disorder necessitating urethral reconstruction. As of March 2011, all five recipients report the transplants have functioned well. [23]
Buccal mucosal tissue harvested under local anesthesia after culturing in the lab when applied through endoscopy after urethrotomy in a pilot study has yielded encouraging results. This method named as BEES-HAUS procedure needs to be validated through a larger multicentric study before becoming a routine application. [24]
The urethra is the tube that connects the urinary bladder to the urinary meatus, through which placental mammals urinate and ejaculate. In non-mammalian vertebrates, the urethra also transports semen but is separate from the urinary tract.
The prostate is an accessory gland of the male reproductive system and a muscle-driven mechanical switch between urination and ejaculation. It is found in all male mammals. It differs between species anatomically, chemically, and physiologically. Anatomically, the prostate is found below the bladder, with the urethra passing through it. It is described in gross anatomy as consisting of lobes and in microanatomy by zone. It is surrounded by an elastic, fibromuscular capsule and contains glandular tissue, as well as connective tissue.
Cystoscopy is endoscopy of the urinary bladder via the urethra. It is carried out with a cystoscope.
In urinary catheterization, a latex, polyurethane, or silicone tube known as a urinary catheter is inserted into the bladder through the urethra to allow urine to drain from the bladder for collection. It may also be used to inject liquids used for treatment or diagnosis of bladder conditions. A clinician, often a nurse, usually performs the procedure, but self-catheterization is also possible. A catheter may be in place for long periods of time or removed after each use.
Hypospadias is a common malformation in fetal development of the penis in which the urethra does not open from its usual location on the head of the penis. It is the second-most common birth defect of the male reproductive system, affecting about one of every 250 males at birth, although when including milder cases, is found in up to 4% of newborn males. Roughly 90% of cases are the less serious distal hypospadias, in which the urethral opening is on or near the head of the penis (glans). The remainder have proximal hypospadias, in which the meatus is all the way back on the shaft of the penis, near or within the scrotum. Shiny tissue or anything that typically forms the urethra instead extends from the meatus to the tip of the glans; this tissue is called the urethral plate.
Urethral sounding is the practice of inserting objects into the urethra for sexual gratification. Urethral dilatation is a urological procedure that uses probes called sounds to enlarge the inside diameter of the urethra and locate obstructions in the urethra, or as a treatment for urethral strictures.
Urinary retention is an inability to completely empty the bladder. Onset can be sudden or gradual. When of sudden onset, symptoms include an inability to urinate and lower abdominal pain. When of gradual onset, symptoms may include loss of bladder control, mild lower abdominal pain, and a weak urine stream. Those with long-term problems are at risk of urinary tract infections.
Urethral meatal stenosis is a narrowing (stenosis) of the opening of the urethra at the external meatus, thus constricting the opening through which urine leaves the body from the urinary bladder.
Hydronephrosis describes hydrostatic dilation of the renal pelvis and calyces as a result of obstruction to urine flow downstream. Alternatively, hydroureter describes the dilation of the ureter, and hydronephroureter describes the dilation of the entire upper urinary tract.
A urethrotomy is an operation which involves incision of the urethra, especially for relief of a stricture. It is most often performed in the outpatient setting, with the patient (usually) being discharged from the hospital or surgery center within six hours from the procedure's inception.
Posterior urethral valve (PUV) disorder is an obstructive developmental anomaly in the urethra and genitourinary system of male newborns. A posterior urethral valve is an obstructing membrane in the posterior male urethra as a result of abnormal in utero development. It is the most common cause of bladder outlet obstruction in male newborns. The disorder varies in degree, with mild cases presenting late due to milder symptoms. More severe cases can have renal and respiratory failure from lung underdevelopment as result of low amniotic fluid volumes, requiring intensive care and close monitoring. It occurs in about one in 8,000 babies.
Neurogenic bladder dysfunction, often called by the shortened term neurogenic bladder, refers to urinary bladder problems due to disease or injury of the central nervous system or peripheral nerves involved in the control of urination. There are multiple types of neurogenic bladder depending on the underlying cause and the symptoms. Symptoms include overactive bladder, urinary urgency, frequency, incontinence or difficulty passing urine. A range of diseases or conditions can cause neurogenic bladder including spinal cord injury, multiple sclerosis, stroke, brain injury, spina bifida, peripheral nerve damage, Parkinson's disease, multiple system atrophy or other neurodegenerative diseases. Neurogenic bladder can be diagnosed through a history and physical as well as imaging and more specialized testing. In addition to symptomatic treatment, treatment depends on the nature of the underlying disease and can be managed with behavioral changes, medications, surgeries, or other procedures. The symptoms of neurogenic bladder, especially incontinence, can severely degrade a person's quality of life.
Urethral cancer is a rare cancer originating from the urethra. The disease has been classified by the TNM staging system and the World Health Organization.
Urethroplasty is the surgical repair of an injury or defect within the walls of the urethra. Trauma, iatrogenic injury and infections are the most common causes of urethral injury/defect requiring repair. Urethroplasty is regarded as the gold standard treatment for urethral strictures and offers better outcomes in terms of recurrence rates than dilatations and urethrotomies. It is probably the only useful modality of treatment for long and complex strictures though recurrence rates are higher for this difficult treatment group.
A retrograde urethrography is a routine radiologic procedure used to image the integrity of the urethra. Hence a retrograde urethrogram is essential for diagnosis of urethral injury, or urethral stricture.
A prostatic stent is a stent used to keep open the male urethra and allow the passing of urine in cases of prostatic obstruction and lower urinary tract symptoms (LUTS). Prostatic obstruction is a common condition with a variety of causes. Benign prostatic hyperplasia (BPH) is the most common cause, but obstruction may also occur acutely after treatment for BPH such as transurethral needle ablation of the prostate (TUNA), transurethral resection of the prostate (TURP), transurethral microwave thermotherapy (TUMT), prostate cancer or after radiation therapy.
Lower urinary tract symptoms (LUTS) refer to a group of clinical symptoms involving the bladder, urinary sphincter, urethra and, in men, the prostate. The term is more commonly applied to men – over 40% of older men are affected – but lower urinary tract symptoms also affect women. The condition is also termed prostatism in men, but LUTS is preferred.
Urodynamic testing or urodynamics is a study that assesses how the bladder and urethra are performing their job of storing and releasing urine. Urodynamic tests can help explain symptoms such as:
Suprapubic aspiration is a procedure to take a urine sample. It involves putting a needle through the skin just above the pubic bone into the bladder. It is typically used as a method to collect urine in child less than 2 years of age who is not yet toilet trained in an effort to diagnose a urinary tract infection.
Bulbar urethral necrosis is a problem that can occur after a pelvic fracture associated urethral distraction defect (PFUDD).