Urethra obstruction

Hoebeke PB, Van Laecke E, Raes A et al (1997) Membrano-bulbo-urethral junction stenosis. Posterior urethra obstruction due to extreme caliber disproportion in the male urethra. Eur Urol 32 480-484 Kawashima A, Sandler CM, Wasserman NF et al (2004) Imaging of urethral disease a pictorial review. Radiographics 24 [Suppl 1] S195-216... 

O The lower urinary tract symptoms and signs of benign prostatic hyperplasia are due to static, dynamic, or detrusor factors. The static factor refers to anatomic obstruction of the bladder neck caused by an enlarged prostate gland. The dynamic factor refers to excessive stimulation of a-adrenergic receptors in the smooth muscle of the prostate, urethra, and bladder neck. The detrusor factor refers to irritability of hypertrophied detrusor muscle as a result of long-standing bladder outlet obstruction. 

Lower tract infections include cystitis (bladder), urethritis (urethra), prostatitis (prostate gland), and epididymitis. Upper tract infections (such as pyelonephritis) involve the kidney and are referred to as pyelonephritis. Uncomplicated UTIs are not associated with structural or neurologic abnormalities that may interfere with the normal flow of urine or the voiding mechanism. Complicated UTIs are the result of a predisposing lesion of the urinary tract such as a congenital abnormality or distortion of the urinary tract, a stone, indwelling catheter, prostatic hypertrophy, obstruction, or neurologic deficit that interferes with the normal flow of urine and urinary tract defenses. 

Intrauterine growth retardation and anomalies of the fetal urinary tract, such as bilateral renal agenesis or obstruction of the urethra, are associated with oligohydramnios, an abnormally low amniotic fluid volume. Increased fluid volume is known as hydramnios (also termed polyhydramnios). Conditions associated with hydramnios are as diverse as maternal diabetes mellitus, severe Rli isoimmune disease, fetal esophageal atresia, multifetal pregnancy, anencephaly, and spina bifida. 

Small, single-use device that is worn in the urethra to provide mechanical obstruction to prevent urine leakage removed for voiding (e.g., FemSoft Insert, Rochester Med. Corp., Stewartville, MN)... 

The symptoms of BPH (c.g., urethral obstruction leading to weak stream, urinary frequency, and nocturia) result from mechanical pressure on the urethra (due to an increase in smooth muscle mass) and an a -mediated increase in smooth muscle tone in the prostate and neck of the bladder. 

The symptoms of BPH stem from obstruction of the urethra by an enlarged prostate and the gradual... 

The medication decreases the mechanical obstruction of the urethra by the prostate. 

Obstruction of the lower urinary apparatus can be caused by primitive lesions of the urethra or lesions secondary to compression by an enlarged prostate or perineal masses. The most frequent cause of non-prostatic obstructive dysuria is acquired stenosis, which can be divided into post-inflammatory, post-traumatic and post-surgical. 

Urethra, clitorial enlargment to penile urethra 558 Uric acid lithiasis 452, 453 Urinary tract infection 65, 303, 511, 512, 643 Urolithiasis 301, 303 Uropathy, obstructive 303, 454 Uterus, absent 562 Uvula, bifid 379... 

The same day, VCU is performed commonly after suprapubic puncture (Fig. 6.3). Aspiration of stagnant urine is performed via a vesical catheter that can be left in place thereafter. All precautions must be taken to ensure sterility given the increased risk of post-procedural infection. Infection could be life threatening for the baby and devastating for renal function. Retrograde opacification would be technically possible since valves produce only one-way obstruction. However, it can be difficult to pass through the bladder neck due to the dilated posterior urethra, which can retain the tip of the tube. 

Ectopic ureterocele develops at the lower end of the upper pole ureter of a duplicated kidney. It is a cyst-like thin-walled structure that is known to be mobile and variable in shape. During fetal life, the ureterocele can prolapse into the posterior urethra and create obstruction (Fig. 6.9). Bilateral hydronephrosis and megacystis can subsequently develop. Clinical diagnosis can be made at birth in girls with a perineal soft tissue mass, megacystis and bilateral urinary tract obstruction. Sonographic diagnosis can be difficult when the ectopic ureterocele has... 

Fig. 6.9. VCU in a female neonate with prenatal diagnosis of megacystis and hydronephrosis. Vesicoureteric reflux into the lower pole of a left duplicated kidney. Left upper pole ureter is obstructed by an ectopic ureterocele that is prolapsed in the urethra during micturition...

Epispadia is part of the heterogeneous exstrophy-epispadia complex. It may occur in males and females. Widening of the pubic symphysis is usually associated. Continence is variable in those patients, so imaging and urodynamic studies in these patients should be directed towards this handicap and the detection of associated anomalies. Duplication of the bulbous urethra is extremely rare. It may be complete or blind-ended, ventral or dorsal (Barbagli et al. 1996). Finally, megalourethra (Stephens and Fortune 1993) is an enlargement of the pendulous urethra with no evidence of distal obstruction. It... 

Cobb BG, Wolf JA, Ansell JS (1968) Congenital stricture of the proximal urethral bulb. J Urol 99 629-631 Dewan PA, Zappala SM, Ransley PG et al (1992) Endoscopic reappraisal of the morphology of congenital obstruction of the posterior urethra. Br J Urol 70 439-444 Dewan PA, Keenan RJ, Morris LL et al (1994) Congenital urethral obstruction Cobb s collar or prolapsed congenital obstructive posterior urethral membrane (COPUM). Br J Urol 73 91-95... 

The more severe cases of proximal hypospadias often show a narrowing of the urethra with signs of urinary outflow obstruction and are commonly associated with cloacal anomalies and female pseudohermaphroditism (Knight et al.l995). 

VCU is also useful because it provides a simultaneous evaluation of the bladder and urethra. The demonstration of voiding dysfunction, bladder wall thickening, or diverticula may help to characterize and understand VUR (Fotter et al. 1986 Koff 1992). Urethral obstruction, whatever its origin, may also be associated with secondary VUR (Fig. 11.7). 

As mentioned above, VUR may be associated with voiding dysfunction furthermore, VUR is frequently associated with bladder outlet obstruction whatever its origin, or with neurogenic bladder disorders (Figs. 11.16, 11.17). Therefore, a VCU is the best-adapted examination for evaluating these patients furthermore, analysis of the micturition phase and evaluation of the urethra must be part of every VCU (Van Gool 1995). 

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