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Birth injuries that result in the formation of fistulas and urinary and fecal incontinence have been found to be strongly associated with economic and cultural factors. Teenagers and women who sustain injuries that develop into ureterovaginal fistulas during childbirth suffer significant social stigma. Ureterovaginal fistulas related to prolonged, obstructed labor are rare in developed nations but are more common in countries where access to emergent obstetrical care is limited.
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.
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.
Urethral strictures after blunt trauma can generally be divided into two sub-types;
- Pelvic fracture-associated urethral disruption occurs in as many as 15% of severe pelvic fractures. These injuries are typically managed with suprapubic tube placement and delayed urethroplasty 3 months later. Early endoscopic realignment may be used in select cases instead of a suprapubic tube, but these patients should be monitored closely as vast majority of them will require urethroplasty.
- Blunt trauma to the perineum compresses the bulbar urethra against the pubic symphysis, causing a "crush" injury. These patients are typically treated with suprapubic tube and delayed urethroplasty.
Other specific causes of urethral stricture include:
- Instrumentation (e.g., after transurethral resection of prostate, transurethral resection of bladder tumor, or endoscopic kidney surgery)
- Infection (typically with Gonorrhea)
- Lichen sclerosus
- Surgery to address hypospadias can result in a delayed urethral stricture, even decades after the original surgery.
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.
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.
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 and may worsen the stricture, making future attempts to surgically repair the urethra more difficult.
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.
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.
Many women delay treatment for decades. Surgeons often will correct the fistula through major gynecological surgery. Newer treatments can include the placement of a stent and is usually successful. In 0.5-2.5% of major pelvic surgeries a ureterovaginal fistula will form, usually weeks later. If the fistula cannot be repaired, the clinician may create a permanent diversion of urine or urostomy. Risks associated with the repair of the fistula are also associated with most other surgical procedures and include the risk of adhesions, disorders of wound healing, infection, ileus, and immobilization. There is a recurrence rate of 5%–15% in the surgical operation done to correct the fistula.
The treatment for PFUDDs is scar excision and primary anastomosis, which means reconnecting the two ends of the urethra that were severed during the pelvic injury. Most patients do well with this but occasionally, stricture of the repair recurs and the patients may require redo surgery.
Surgery involves making an incision between the anus and scrotum (perineal incision) and dissecting out the bulbar urethra and locating the scar and membranoprostatic urethra. Dissecting the bulbar urethra destroys the antegrade blood flow. However, this urethra still does well since in still gets retrograde blood flow from the dorsal arteries. When patients have erectile dysfunction, the dorsal arteries do not work well and therefore the bulbar urethra does not get a good blood supply.
A pelvic fracture can cause the urethra to separate, leading to a variable length of scar that can severely hamper the ability to urinate normally. The urethra is a tubular conduit that transports urine out of the bladder. The bulbar urethra is a segment of the male urethra that is in between the penile urethra and the membrano-prostatic urethra that typically has a robust blood supply. This blood supply includes antegrade flow from the paired bulbar arteries and circumflex arteries, and retrograde flow from the paired dorsal arteries of the penis.
Bladder stones may occur whenever the kidneys, bladder, or ureters become inflamed, which may occur when the urine becomes too concentrated or when the body becomes dehydrated. Minerals such as calcium and magnesium crystallize into the stones, which then can cause such symptoms as lower back or abdominal pain or difficulty with urination. The use of urinary catheters may cause a bladder stone. Individuals who are paralyzed or are unable to adequately pass urine may require the use of small plastic tubes (catheters) placed into the bladder. The use of these tubes may lead to an infection, which irritates the bladder, resulting in stone formation. Finally, a kidney stone may travel down the ureter into the bladder and become a bladder stone. There is some evidence indicating that chronic irritation of the bladder by retained stones may increase the chance of bladder cancer. Urinary schistosomiasis, a disease caused by the digenean trematode "Schistosoma haematobium", has been implicated in the development of vesical calculi. However, evidence accumulated thus far has not supported this hypothesis.
The Gold standard for all Urinary incontinence is an urodynamic study that looks for bladder capacity, detrusor stability, contractility and voiding ability (Cystometry)
Prostatorrhea is the emission of prostatic secretions during straining associated with urination or defecation.
Lesions affecting sacral segments or peripheral autonomic fibres result in atonic bladder with loss of sphincteric coordination. This results in loss of detrusor contraction, difficulty in initiating micturition and overflow incontinence. Anticholinergic side effects of certain medications (for example, certain antipsychotics and antidepressants) may cause urinary retention which may lead to overflow incontinence. Alpha-adrenergic agonists may cause urinary retention by stimulating the contraction of the urethral sphincter. Calcium channel blockers may decrease the contractility of the smooth muscle tissue in the urinary bladder, causing urinary retention with overflow incontinence.
Epidural anesthesia and delivery also can cause the overflow incontinence.
The best way to prevent bladder stones is to drink plenty of liquids. Juices containing citrates are thought to reduce the risk of stone formation. A study published in the "Clinical Journal of the American Society of Nephrology" indicate orange juice is more effective at preventing stone formation than other citrus juices. Men who have difficulty with urination due to prostatic hypertrophy should seek treatment. In those with benign prostatic hyperplasia urinating in a sitting position appears to improve bladder emptying which might decrease bladder stones in this group.
Without diagnostic evaluation, the cause of UAB is unclear, as there are multiple possible causes. UAB symptoms can accurately reflect impaired bladder emptying due either to DU or obstruction (normal or large storage volumes, elevated post-void residual volume), or can result from a sense of incomplete emptying of a hypersensitive bladder (small storage volumes, normal or elevated postvoid residual volume). UAB potentially might also result from inaccurate perceptions of bladder function, such as in neurologic or psychiatric disease. DU itself is often linked to a weak detrusor muscle (impaired contractility), however this association is weak. Both UAB and DU have been associated with diminished sensitivity to bladder volumes rather than objective detrusor weakness, suggesting both symptoms (UAB) and function (DU) have a significant component of sensory dysfunction, leading to impaired bladder sensations and control (Smith et al., 2015).
The underlying contributors to UAB include neurologic disease, metabolic disease (e.g. diabetes), chronic bladder outlet obstruction (e.g. obstructive BPH or complications of anterior vaginal surgery), cognitive decline (such as with aging), psychiatric disorders, and adverse effects of medications. Additionally, structural abnormalities expanding the urinary reservoir beyond the bladder, such as massive vesicoureteral reflux or large bladder diverticulae, can result in UAB. While aging itself is often associated with UAB (and DU), there is scant evidence to support this claim.
The female homolog to the male verumontanum from which the valves originate is the hymen.
The risk of the development of a lymphocele is positively correlated to the extent of the removal of lymphatic tissue during surgery (lymphadenectomy). Surgery destroys and disrupts the normal channels of lymph flow. If the injury is minor, collateral channels will transport lymph fluid, but with extensive damage, fluid may accumulate in an anatomic space resulting in a lymphocele. Typical operations leading to lymphocysts are renal transplantation and radical pelvic surgery with lymph node removal because of prostatic or gynecologic cancer. Other factors that may predispose of lymphocele development are preoperative radiation therapy, heparin prophylaxis (used to prevent deep vein thrombosis), and tumor characteristics. After radical surgery for cervical and ovarian cancer studies with follow-up CT found lymphoceles in 20% and 32%, respectively. Typically they develop within 4 months after surgery.
Underactive Bladder Syndrome (UAB) describes symptoms of difficulty with bladder emptying, such as hesitancy to start the stream, a poor or intermittent stream, or sensations of incomplete bladder emptying. The physical finding of detrusor pressurization of insufficient strength or duration to ensure timely and efficient bladder emptying is properly termed "detrusor underactivity" (DU) (Abrams et al., 2002). Historically, UAB and DU (as well as others such as 'bladder underactivity') have been often used interchangeably (Rigby D, 2005), leading to both terminologic and pathophysiologic confusion.
Patients with UAB have a diminished sense of bladder filling and consequently are often found to have DU as an underlying finding, however bladder outlet obstruction and less frequently volume hypersensitivity ("OAB") can be associated with UAB symptoms (Chapple et al., 2015).
Involutional stenosis is probably the most common cause of NLD obstruction in older persons. It affects women twice as frequently as men. Although the inciting event in this process is unknown, clinicopathologic study suggests that compression of the lumen of the NLD is caused by inflammatory infiltrates and edema. This may be the result of an unidentified infection or possibly an autoimmune disease.
Retrograde ejaculation occurs when semen, which would, in most cases, be ejaculated via the urethra, is redirected to the urinary bladder. Normally, the sphincter of the bladder contracts before ejaculation forcing the semen to exit via the urethra, the path of least resistance. When the bladder sphincter does not function properly, retrograde ejaculation may occur. It can also be induced deliberately by a male as a primitive form of male birth control (known as "coitus saxonicus") or as part of certain alternative medicine practices.
Studies indicate that dietary patterns may affect development of BPH, but further research is needed to clarify any important relationship. Studies from China suggest that greater protein intake may be a factor in development of BPH. Men older than 60 in rural areas had very low rates of clinical BPH, while men living in cities and consuming more animal protein had a higher incidence. On the other hand, a study in Japanese-American men in Hawaii found a strong negative association with alcohol intake, but a weak positive association with beef intake. In a large prospective cohort study in the US (the Health Professionals Follow-up Study), investigators reported modest associations between BPH (men with strong symptoms of BPH or surgically confirmed BPH) and total energy and protein, but not fat intake. There is also epidemiological evidence linking BPH with metabolic syndrome (concurrent obesity, impaired glucose metabolism and diabetes, high triglyceride levels, high levels of low-density cholesterol, and hypertension).
Certain medications can increase urination difficulties by increasing bladder outlet resistance by increasing smooth muscle tone at the prostate or bladder neck and contribute to LUTS. Alpha-adrenergic agonist medications, such as decongestants with pseudoephedrine can increase bladder outlet resistance. In contrast, calcium channel blockers and anticholinergic medications can worsen urinary retention by promoting bladder muscle relaxation. Diuretic medications such as loop diuretics (e.g., furosemide) or thiazides (e.g., chlorthalidone) can cause or worsen urinary frequency and nighttime awakenings to urinate.
Treatment of hydronephrosis focuses upon the removal of the obstruction and drainage of the urine that has accumulated behind the obstruction. Therefore, the specific treatment depends upon where the obstruction lies, and whether it is acute or chronic.
Acute obstruction of the upper urinary tract is usually treated by the insertion of a nephrostomy tube. Chronic upper urinary tract obstruction is treated by the insertion of a ureteric stent or a pyeloplasty.
Lower urinary tract obstruction (such as that caused by bladder outflow obstruction secondary to prostatic hypertrophy) is usually treated by insertion of a urinary catheter or a suprapubic catheter.Surgery is not required in all prenatally detected cases.
Sinus disease often occurs in conjunction with, and in other instances may contribute to the development of NLD obstruction. Patients should be asked about previous sinus surgery, as the NLD is sometimes damaged when the maxillary sinus ostium is being enlarged anteriorly.