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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. Urethroplasty can be performed safely on men of all ages.
In the posterior urethra, anastomotic urethroplasty (with or without preservation of bulbar arteries) is typically performed after removing scar tissue.
In the bulbar urethra, 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).
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 setting, depending on stricture location, severity, cause and patient or surgeon preference.
Urethral diverticulum is often an incidental finding. It can be diagnosed using magnetic resonance imaging and/or micturating cystourethrography. Other studies that can be used to diagnose urethral diverticulum include intravenous urography, urethroscopy, and/or ultrasound. Conditions that should be distinguished from urethral diverticulum in a differential diagnosis include overactive bladder, Gartner's duct cyst, Gartner's duct abscess, ectopic caeco-ureterocele, interstitial cystitis, pelvic inflammatory disease, endometriosis, and cancer.
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.
At the present time, there is one temporary prostatic stent that has received U.S. Food and Drug Administration (FDA) approval. The Spanner
temporary prostatic stent maintains urine flow and allows natural voluntary urination. The prostatic stent is a completely internal device and can be inserted and removed as easily as a Foley catheter. It permits normal bladder and sphincter functioning and can be worn comfortably by patients. The temporary prostatic stent is typically used to help patients maintain urine flow after procedures that cause prostatic swelling, such as brachytherapy, cryotherapy, TUMT, TURP. It has also become an effective differential diagnostic tool for identifying poor bladder function separate from prostatic obstruction.
Low-volume, runny/fluid semen (oligospermia) or no semen at all (dry ejaculation/aspermia) are a logical consequence of an obstruction downstream of the seminal vesicles which contribute most to the volume of the semen. Usually, men will be able to observe a runny/fluid, low-volume semen by themselves during masturbation. Since the seminal vesicles contain a viscous, alkaline fluid rich in fructose, a chemical analysis of the semen of affected men will result in a low concentration of fructose and a low pH. A microscopic semen analysis will reveal aspermia/azoospermia.
In contrast, if both vasa deferentia are obstructed (which may be the result of intended sterilization), a semen analysis will also reveal aspermia/azoospermia, but an almost normal volume of the semen, since the efflux of the seminal vesicles is not hindered. This is because approx. 80% of the volume of the semen is the gel-like fluid originating from the seminal vesicles whereas the fraction from the testicles / epididymis, which contains the spermatozoa accounts for only 5–10% of the volume of the semen. In addition, if an obstruction of the vasa deferentia is the cause for the azoospermia, the concentration of fructose in the semen will also be normal, since the fructose comes primarily from the fluid stored in the seminal vesicles. If the seminal-vesicles contain spermatozoa, but the semen does not, the obstruction must be downstream of the seminal vesicles and the ejaculatory ducts are very likely to be obstructed, provided that other causes for a dry ejaculation/aspermia such as an retrograde ejaculation are ruled out.
Attempts are sometimes made to diagnose an ejaculatory duct obstruction by means of medical imaging, e.g. transrectal ultrasound or MRI, or by transrectal needle-aspiration of the seminal vesicles. However transrectal ultrasound has a relatively low sensitivity of approx. 50% and thus is only a tool to rule-out cysts in the region of the orifices but is not sufficient to rule out an obstruction of the ejaculatory ducts due to other causes. In approx. 50% of cases of unexplained low-volume azoospermia MRI and TRUS do not reveal any pathological findings, because it is difficult to see alterations in a narrowed, scarred duct with these methods. Due to the blockage of ejaculatory ducts, enlarged seminal vesicles are frequently seen in patients with ejaculatory duct obstructions. However, this is again neither a proof of an obstruction nor do normal-sized seminal vesicles rule-out an obstruction of the ejaculatory ducts. Since ejaculatory duct obstruction is a relatively rare cause of infertility, this possibility may be unfamiliar to some physicians, even some urologists.
The primary treatment for urethral diverticulum is surgical. The surgery is conducted transvaginally, usually when there is no acute inflammation to better aid dissection of the delicate tissues.
There are two types of prostatic stent: temporary and permanent.
Although a permanent prostatic stent is not a medical treatment, it falls under the classification of a surgical procedure. Placement of a permanent prostatic stent is carried out as an outpatient treatment under local, topical or spinal anesthesia and usually takes about 15–30 minutes.
A temporary prostatic stent can be inserted in a similar manner to a Foley catheter, requiring only topical anesthesia.
Abdominal ultrasound is of some benefit, but not diagnostic. Features that suggest posterior urethral valves are bilateral hydronephrosis, a thickened bladder wall with thickened smooth muscle trabeculations, and bladder diverticula.
Voiding cystourethrogram (VCUG) is more specific for the diagnosis. Normal "plicae circularis" are variable in appearance and often not seen on normal VCUGs. PUV on voiding cystourethrogram is characterized by an abrupt tapering of urethral caliber near the verumontanum, with the specific level depending on the developmental variant. Vesicoureteral reflux is also seen in over 50% of cases. Very often the posterior urethra maybe dilated thus making the abrupt narrowing more obvious. the bladder wall may show trabeculations or sacculations or even diverticuli.
Diagnosis can also be made by cystoscopy, where a small camera is inserted into the urethra for direct visualization of the posteriorly positioned valve. A limitation of this technique is that posterior valve tissue is translucent and can be pushed against the wall of the urethra by inflowing irrigation fluid, making it difficult to visualize. Cystoscopy may also demonstrate the bladder changes.
Centers in Europe and Japan have also had excellent results with cystosonography, although it has not been approved for use in the United States yet.
Penile color duplex doppler ultrasound can help with preoperative planning to minimize bulbar necrosis.
Pelvic floor dysfunction can be diagnosed by history and physical exam, though it is more accurately graded by imaging. Historically, fluoroscopy with defecography and cystography were used, though modern imaging allows the usage of MRI to complement and sometimes replace fluoroscopic assessment of the disorder, allowing for less radiation exposure and increased patient comfort, though an enema is required the evening before the procedure. Instead of contrast, ultrasound gel is used during the procedure with MRI. Both methods assess the pelvic floor at rest and maximum strain using coronal and sagittal views. When grading individual organ prolapse, the rectum, bladder and uterus are individually assessed, with prolapse of the rectum referred to as a rectocele, bladder prolapse through the anterior vaginal wall a cystocele, and small bowel an enterocele.
To assess the degree of dysfunction, three measurements must be taken into account. First, an anatomic landmark known as the pubococcygeal line must be determined, which is a straight line connecting the inferior margin of the pubic symphysis at the midline with the junction of the first and second coccygeal elements on a sagittal image. After this, the location of the puborectalis muscle sling is assessed, and a perpendicular line between the pubococcygeal line and muscle sling is drawn. This provides a measurement of "pelvic floor descent", with descent greater than 2 cm being considered mild, and 6 cm being considered severe. Lastly, a line from the pubic symphysis to the puborectalis muscle sling is drawn, which is a measurement of the pelvic floor hiatus. Measurements of greater than 6 cm are considered mild, and greater than 10 cm severe. The degree of organ prolapse is assessed relative to the hiatus. The grading of "organ prolapse" relative to the hiatus is more strict, with any descent being considered abnormal, and greater than 4 cm being considered severe.
Upon delivery, the exposed bladder is irrigated and a non-adherent film is placed to prevent as much contact with the external environment as possible. In the event the child was not born at a medical center with an appropriate exstrophy support team then transfer will likely follow. Upon transfer, or for those infants born at a medical center able to care for bladder exstrophy, imaging may take place in the first few hours of life prior to the child undergoing surgery.
Primary (immediate) closure is indicated only in those patients with a bladder of appropriate size, elasticity, and contractility as those patients are most likely to develop a bladder of adequate capacity after early surgical intervention.
Conditions that are absolute contraindications despite bladder adequacy include duplication of the penis or scrotum and significant bilateral hydronephrosis.
Patients with incontinence should be referred to a medical practitioner specializing in this field. Urologists specialize in the urinary tract, and some urologists further specialize in the female urinary tract. A urogynecologist is a gynecologist who has special training in urological problems in women. Family physicians and internists see patients for all kinds of complaints, and are well trained to diagnose and treat this common problem. These primary care specialists can refer patients to urology specialists if needed.
A careful history taking is essential especially in the pattern of voiding and urine leakage as it suggests the type of incontinence faced. Other important points include straining and discomfort, use of drugs, recent surgery, and illness.
The physical examination will focus on looking for signs of medical conditions causing incontinence, such as tumors that block the urinary tract, stool impaction, and poor reflexes or sensations, which may be evidence of a nerve-related cause.
A test often performed is the measurement of bladder capacity and residual urine for evidence of poorly functioning bladder muscles.
Other tests include:
- Stress test – the patient relaxes, then coughs vigorously as the doctor watches for loss of urine.
- Urinalysis – urine is tested for evidence of infection, urinary stones, or other contributing causes.
- Blood tests – blood is taken, sent to a laboratory, and examined for substances related to causes of incontinence.
- Ultrasound – sound waves are used to visualize the kidneys, ureters, bladder, and urethra.
- Cystoscopy – a thin tube with a tiny camera is inserted in the urethra and used to see the inside of the urethra and bladder.
- Urodynamics – various techniques measure pressure in the bladder and the flow of urine.
Patients are often asked to keep a diary for a day or more, up to a week, to record the pattern of voiding, noting times and the amounts of urine produced.
Research projects that assess the efficacy of anti-incontinence therapies often quantify the extent of urinary incontinence. The methods include the 1-h pad test, measuring leakage volume; using a voiding diary, counting the number of incontinence episodes (leakage episodes) per day; and assessing of the strength of pelvic floor muscles, measuring the maximum vaginal squeeze pressure.
Cystoceles are treated with a surgical procedure known as a Burch colposuspension, with the goal of suspending the prolapsed urethra so that the urethrovesical junction and proximal urethra are replaced in the pelvic cavity. Uteroceles are treated with hysterectomy and uterosacral suspension. With enteroceles, the prolapsed small bowel is elevated into the pelvis cavity and the rectovaginal fascia is reapproximated. Rectoceles, in which the anterior wall of the rectum protrudes into the posterior wall of the vagina, require posterior colporrhaphy.
If suspected antenatally, a consultation with a paediatric surgeon/ paediatric urologist maybe indicated to evaluate the risk and consider treatment options.
Treatment is by endoscopic valve ablation. Fetal surgery is a high risk procedure reserved for cases with severe oligohydramnios, to try to limit the associated lung underdevelopment, or pulmonary hypoplasia, that is seen at birth in these patients. The risks of fetal surgery are significant and include limb entrapment, abdominal injury, and fetal or maternal death. Specific procedures for "in utero" intervention include infusions of amniotic fluid, serial bladder aspiration, and creating a connection between the amniotic sac and the fetal bladder, or vesicoamniotic shunt.
There are three specific endoscopic treatments of posterior urethral valves:
- Vesicostomy followed by valve ablation - a stoma, or hole, is made in the urinary bladder, also known as "low diversion", after which the valve is ablated and the stoma is closed.
- Pyelostomy followed by valve ablation - stoma is made in the pelvis of the kidney as a slightly "high diversion", after which the valve is ablated and the stoma is closed
- Primary (transurethral) valve ablation - the valve is removed through the urethra without creation of a stoma
The standard treatment is primary (transurethral) ablation of the valves. Urinary diversion is used in selected cases, and its benefit is disputed.
Following surgery, the follow-up in patients with posterior urethral valve syndrome is long term, and often requires a multidisciplinary effort between paediatric surgeons/ paediatric urologists, pulmonologists, neonatologists, radiologists and the family of the patient. Care must be taken to promote proper bladder compliance and renal function, as well as to monitor and treat the significant lung underdevelopment that can accompany the disorder. Definitive treatment may also be indicated for the vesico-ureteral reflux.
No useful studies have been done to determine whether acupuncture can help people with stress urinary incontinence.
The Gold standard for all Urinary incontinence is an urodynamic study that looks for bladder capacity, detrusor stability, contractility and voiding ability (Cystometry)
A method to treat ejaculatory duct obstruction is transurethral resection of the ejaculatory ducts (TURED). This operative procedure is relatively invasive, has some severe complications, and has led to natural pregnancies of their partners in approximately 20% of affected men. A disadvantage is the destruction of the valves at the openings of the ejaculatory ducts into the urethra such that urine may flow backwards into the seminal vesicles. Another, experimental approach is the recanalization of the ejaculatory ducts by transrectal or transurethral inserted balloon catheter. Though much less invasive and preserving the anatomy of the ejaculatory ducts, this procedure is probably not completely free of complications either and success rates are unknown. There is a clinical study currently ongoing to examine the success rate of recanalization of the ejaculatory ducts by means of balloon dilation.
Usually, affected men have a normal production of spermatozoa in their testicles, so that after spermatozoa were harvested directly from the testes e.g. by TESE, or the seminal vesicles (by needle aspiration) they and their partners are potentially candidates for some treatment options of assisted reproduction e.g. in-vitro fertilisation. Note that in this case, most of the treatment (e.g. ovarian stimulation and transvaginal oocyte retrieval) is transferred to the female partner.
A meta-analysis on the influence of voiding position on urodynamics in healthy males and males with LUTS showed that in the sitting position, the residual urine in the bladder was significantly reduced. The other parameters, namely the maximum urinary flow and the voiding time were increased and decreased respectively. For healthy males, no influence was found on these parameters, meaning that they can urinate in either position.
Imaging studies, such as an intravenous urogram (IVU), renal ultrasonography, CT or MRI, are also important investigations in determining the presence and/ or cause of hydronephrosis. Whilst ultrasound allows for visualisation of the ureters and kidneys (and determine the presence of hydronephrosis and / or hydroureter), an IVU is useful for assessing the anatomical location of the obstruction. Antegrade or retrograde pyelography will show similar findings to an IVU but offer a therapeutic option as well. Real-time ultrasounds and Doppler ultrasound tests in association with vascular resistance testing helps determine how a given obstruction is effecting urinary functionality in hydronephrotic patients.
In determining the cause of hydronephrosis, it is important to rule out urinary obstruction. One way to do this is to test the kidney function. This can be done by, for instance, a diuretic intravenous pyelogram, in which the urinary system is observed radiographically after administration of a diuretic, such as 5% mannitol, and an intravenous iodine contrast. The location of obstruction can be determined with a Whittaker (or pressure perfusion) test, wherein the collecting system of the kidney is accessed percutaneously, and the liquid is introduced at high pressure and constant rate of 10ml/min while measuring the pressure within the renal pelvis. A rise in pressure above 22 cm HO suggests that the urinary collection system is obstructed. When arriving at this pressure measurement, bladder pressure is subtracted from the initial reading of internal pressure. (The test was first described by Whittaker in 1973 to test the hypothesis that patients' whose hydronephrosis persists after the posterior urethral valves have been ablated usually have ureters that are not obstructed, even though they may be dilated.)
Kay recommends that a neonate born with untreated in utero hydronephrosis receive a renal ultrasound within two days of birth. A renal pelvis greater than 12mm in a neonate is considered abnormal and suggests significant dilation and possible abnormalities such as obstruction or morphological abnormalities in the urinary tract.
The choice of imaging depends on the clinical presentation (history, symptoms and examination findings). In the case of renal colic (one sided loin pain usually accompanied by a trace of blood in the urine) the initial investigation is usually a spiral or helical CT scan. This has the advantage of showing whether there is any obstruction of flow of urine causing hydronephrosis as well as demonstrating the function of the other kidney. Many stones are not visible on plain X-ray or IVU but 99% of stones are visible on CT and therefore CT is becoming a common choice of initial investigation. CT is not used however, when there is a reason to avoid radiation exposure, e.g. in pregnancy.
For incidentally detected prenatal hydronephrosis, the first study to obtain is a postnatal renal ultrasound, since as noted, many cases of prenatal hydronephrosis resolve spontaneously. This is generally done within the first few days after birth, although there is some risk that obtaining an imaging study this early may miss some cases of mild hydronephrosis due to the relative oliguria of a newborn. Thus, some experts recommend obtaining a follow up ultrasound at 4–6 weeks to reduce the false-negative rate of the initial ultrasound. A voiding cystourethrogram (VCUG) is also typically obtained to exclude the possibility of vesicoureteral reflux or anatomical abnormalities such as posterior urethral valves. Finally, if hydronephrosis is significant and obstruction is suspected, such as a ureteropelvic junction (UPJ) or ureterovesical junction (UVJ) obstruction, a nuclear imaging study such as a MAG-3 scan is warranted.
In a small retrospective study of 25 pregnancies five factors were found to be strongly associated with a prenatal diagnosis of bladder exstrophy:
- Inability to visualize the bladder on ultrasound
- A lower abdominal bulge
- A small penis with anteriorly displaced scrotum
- A low set umbilical insertion
- Abnormal widening of the iliac crests
While a diagnosis of bladder exstrophy was made retrospectively in a majority of pregnancies, in only three cases was a prenatal diagnosis made.
The diagnosis of bladder stone includes urinalysis, ultrasonography, x rays or cystoscopy (inserting a small thin camera into the urethra and viewing the bladder). The intravenous pyelogram can also be used to assess the presence of kidney stones. This test involves injecting a radiocontrast agent which is passed into the urinary system. X-ray images are then obtained every few minutes to determine if there is any obstruction to the contrast as it is excreted into the bladder. Today, intravenous pyelogram has been replaced at many health centers by CT scans. CT scans are more sensitive and can identify very small stones not seen by other tests.
In rare cases, a surgeon implants an artificial urinary sphincter, a doughnut-shaped sac that circles the urethra. A fluid fills and expands the sac, which squeezes the urethra closed. By pressing a valve implanted under the skin, the artificial sphincter can be deflated. This removes pressure from the urethra, allowing urine from the bladder to pass.
Diagnosis is typically based on symptoms. Conditions that may result in similar symptoms include testicular torsion, inguinal hernia, and testicular cancer. Ultrasound can be useful if the diagnosis is unclear.
Epididymitis usually has a gradual onset. Typical findings are redness, warmth and swelling of the scrotum, with tenderness behind the testicle, away from the middle (this is the normal position of the epididymis relative to the testicle). The cremasteric reflex (elevation of the testicle in response to stroking the upper inner thigh) remains normal. This is a useful sign to distinguish it from testicular torsion. If there is pain relieved by elevation of the testicle, this is called Prehn's sign, which is, however, non-specific and is not useful for diagnosis.
Before the advent of sophisticated medical imaging techniques, surgical exploration was the standard of care. Today, Doppler ultrasound is a common test: it can demonstrate areas of blood flow and can distinguish clearly between epididymitis and torsion. However, inasmuch as torsion and other sources of testicular pain can consistently be determined by palpation alone, some studies have suggested that the only real benefit of an ultrasound, which is a fairly expensive procedure (~US$300 to US$800 in 2013), is to assure the patient that he does not have testicular cancer. Nuclear testicular blood flow testing is rarely used.
Additional tests may be necessary to identify underlying causes. In younger children, a urinary tract anomaly is frequently found. In sexually active men, tests for sexually transmitted diseases may be done. These may include microscopy and culture of a first void urine sample, Gram stain and culture of fluid or a swab from the urethra, nucleic acid amplification tests (to amplify and detect microbial DNA or other nucleic acids) or tests for syphilis and HIV.
Urinary tract obstruction as a congenital disorder results in oligohydramnios which in turn can lead to the Potter sequence of atypical physical appearance. Pulmonary hypoplasia is by far the main cause of death in the early neonatal period for children with congenital lower urinary tract obstruction.
Fetal surgery of congenital lower urinary tract obstruction seems to improve survival, according to a randomized yet small study.
Jackstone calculi are rare bladder stones that have an appearance resembling toy jacks. They are almost always composed of calcium oxalate dihydrate and consist of a dense central core and radiating . They are typically light brown with dark patches and are usually formed in the urinary bladder and rarely in the upper urinary tract. Their appearance on plain radiographs and computed tomography in human patients is usually easily recognizable. Jackstones often must be removed via cystolithotomy.