Reflux as a cause of end stage kidney disease: report of 32 cases

Of 32 patients with end stage renal failure secondary to bilateral, primary, low pressure reflux 10 had sterile reflux and 22 had reflux associated with recurrent urinary tract infection. These cases clearly document a potential terminal phase in the natural history of reflux. In addition, the study indicates the absolute necessity of early diagnosis and surgical correction of severe reflux, regardless of whether the reflux is sterile or associated with infection, and before chemical evidence of renal functional impairment.

Colpocystourethropexy: the way we do it

In pure stress urinary incontinence the sphincteric mechanism is intact. Restoration of normal position and support to the vesicourethral segment usually re-establish normal sphincteric function. A suprapublic approach is used to gain adequate mobilization of the anteriorr vaginal wall and vesicourethral segment. Full thickness sutures applied in the anterior vaginal wall as far lateral from the urethra as possible are then tied to Cooper's ligament. Forward and upward lifting of the vesicourethral segment is achieved but the urethra is free in a wide retropubic space. Normal position with limited mobility of the sphincteric segment is attained, yet compression or obstruction of the urethra and surgical trauma to the delicate sphincteric musculature are avoided. Adsorbable sutures are used. Permanent fixation is to be achieved by the postoperative fibrosis made possible after all retropubic fat has been cleared away. This technique has been uniformly successful in virginal cases and in the great majority of the least favorable cases, after repeated failures. Adequate mobilization proper placement of sutures and prevention of compression and surgical damage are the keys to longlasting successful repair.

Urethrosphincteric reconstruction for congenitally absent urethra

Three female patients with complete urinary incontinence owing to congenital absence of the urethra associated with complex congenital anomalies involving the caudal end of the urogenital sinus are reported. A sphincteric tube constructed from a flap of the anterior bladder wall was positioned in place of the missing urethra. Abundance of circularly oriented fibers in this neourethra provided sphincteric function sufficient to maintain continence and eliminate the need for urinary diversion. Details of the congenital anomalies and reconstructive techniques are discussed.

Embryologic basis for lower ureteral anomalies: a hypothesis

A hypothesis for the embryogenesis of lower ureteral anomalies invokes variations in location and number of ureteral buds on the mesonephric duct. Such vagaries determine the length of the common nephric duct and the time of meeting of the ureteral bud (or buds) with the urogenital sinus. These factors in turn affect the density of the mesenchymal tissue and its mass in relation to the adjoining structures and, ultimately, the musculature of the trigone as well as the level of the ureteral hiatus and the musculature of the bladder base. Primary reflux, ureteral ectopy, ureteral duplication, ureterocele, functional ureteral obstruction, and congenital strictures are viewed and possibly explained in the light of the embryonal variations mentioned.

Male epispadias: surgical repairs of urethropenile deformity

A surgical technique for the repair of complete epispadias, with emphasis on correction of the urethropenile deformity and attempt to restore normal anatomic relations has been presented. The epispadiac orifice is dissected and followed proximally to beyond the bladder neck, then brought out perineally between the bifurcated crura. The penis is denuded from its skin, then embedded in the scrotum, except for the glans penis which protrudes from the midscrotum. Penile skin is folded into a tube to be used later for urethral reconstruction. Excellent cosmetic and functional results are consistently obtained by this multi-stage technique.

Voiding pressure as it relates to outlet and/or sphincteric resistance

Electrically quantitated and controlled detrusor contraction can produce either minimal or excessive rise in intravesical pressure depending upon openness or occlusion of the bladder outlet. Higher rise in intravesical pressure thus does not imply stronger detrusor contraction but should be viewed as a reflection of the outflow resistance mechanism. Possible damaging hydrodynamic effect of sudden partial or complete functional occlusion of the bladder outlet by intermittent or sustained voluntary sphincter activity is illustrated.

Urodynamic evaluation of a chronically implanted bladder pacemaker

A "chronic" study of an implantable bladder pacemaker revealed that, although the electrode array did not significantly impair vesical function during the 10 weeks of research, electric stimulation did spread to the voluntary perineal musculature. There was also a drop in bladder response to the same stimulation parameters, probably due to progressive development of fibrous reaction and encasement of electrodes.

Controlled electrical bladder evacuation via stimulation of the sacral micturition center or direct detrusor stimulation

Electrical stimulation of the spinal cord and of the detrusor was compared in 5 'acute' dogs. Strong detrusor contraction and rise in intravesical pressure were obtained either way but, with spinal cord stimulation, concomitant rise in urethral resistance prevented micturition. Stimulation with a bladder pacemaker induced detrusor contraction high enough to overcome outflow resistance, thus was more effective in initiating voiding.

Studies on vesicourethral reflexes. II. Urethral sphincteric responses to spinal cord stimulation

A bipartite bladder model was developed with and without complete muscular separation in order to isolate and analyze separately sphincteric and detrusor responses. Spinal cord stimulation of the sacral micturition center evoked responses in the detrusor compartment as well as in the urethral sphincteric compartment. The micturition center was easily definable in the spinal cord at a variable point lying in the segment L51/2 to L6 vertebral levels. It was not possible to isolate a separate detrusor center from a sphincteric center. They did overlap-with the sphincteric center extending both above and below the detrusor center. Parameters of stimulation were tested and it was noted that 1 to 3 v, frequency of 10 to 15 cps, and duration of 1 msec gave the optimal responses. Complte muscular separation did not alter sphincteric response to spinal cord stimulation. Nerve-mediated impulses resulted in rise in detrusor pressure and a simultaneous rise in urethral pressure that interfered with proper voiding and hindered bladder emptying. This problem remains to be solved before central spinal cord stimulation for the purpose of controlled bladder evacuation becomes fully effective.

Spinal cord stimulation versus detrusor stimulation. A comparative study in six "acute" dogs

Spinal cord stimulation and direct bladder stimulation were evaluated in an "acute" comparative study of six dogs. Both means were effective in inducing strong detrusor contraction and rise in intravesical pressure. Spinal cord stimulation, however, induced greater rise in outflow resistance than did direct bladder stimulation. Effective net intravesical pressure was higher with direct stimulation and thus more successful in achieving bladder emptying.

Studies on the feasibility of urinary bladder evacuation by direct spinal cord stimulation. I. Parameters of most effective stimulation

In 30 female dogs, spinal cord stimulation was tested to find the optimal parameters producing good voiding and, hopefully, total bladder emptying. Twelve different electrodes or application modifications were examined. Variable frequencies, stimulus duration, and voltages were applied. Search of the site of highest detrusor response (micturition center) was easily identifiable. It became obvious that electrode design was not of critical importance: the responses were basically the same whether we used the wrap-around electrode, which stimulates an entire level, or the coaxial electrode which theoretically limits the current spread around its minute exposed tip. The stimulation parameters that gave the best results were: 2 to 5 volts; frequency: 10 to 15 cps; duration 1 msec. The site of highest detrusor response was round vertebral level L5 1/2, corresponding to cord level S2-4. Generally, no voiding was obtained because of too high sphincteric contraction during stimulation; it appeared that a sphincteric center overlaps the micturition center in either direction. To achieve successful voiding during stimulation, a separation of these two centers with selective stimulation of the detrusor center is necessary, eleiminating sphincteric contraction.

Urethral responses to autonomic nerve stimulation

Urethral contraction in response to cholinergic stimulation has been repeatedly proved and is a universally accepted fact. The adrenergic response is still disputed: (1) Is it a contraction or a relaxation, or a combination of both? (2) Where are the adrenergic receptors? Are they on the intrinsic urethral smooth muscles (with a biphasic response); in two different structures of the same organ (urethral and vascular smooth muscles); or on two anatomically different urethral smooth muscular units? Sympathomimetic and hypogastric nerve stimulation alone, as well as with pharmacologic blockade, showed that the contraction response to adrenergics is independent of the pelvic nerve and does persist even after urethral smooth muscle blockade by atropine, but is abolished after alpha blockade by phentolamine. The same contraction response, manifested in rise in intraurethral pressure, can be induced by pure vasoconstrictors. The relaxation response is reduced by beta blockade. Whether it is the direct response of a specific urethral group of musculature to sympathetic stimulation or an indirect urethral response to trigonal activity in answer to the same stimulus is discussed.

A case against incorporation of bowel segments into the closed urinary system

Five patients in whom isolated ileal or ileocecal segments had been incorporated into the urinary tract suffered complications that ended in excision of the bowel segment. A bowel segment functions if it does not meet resistance or increased intraluminal pressures. In a closed system these 2 evils are working constantly against the loop of bowel, subjecting it to growing distension, dilatation and redundancy and, inevitably, residual urine, urinary tract infection, stone formation, electrolyte imbalance and progressive deterioration of the upper urinary tract ensue. What was initially meant to save kidney function causes instead renal damage and eventually total loss of function.

Recovery of bladder function after spinal cord transection

All dogs having undergone spinal cord transection in our study exhibited a postoperative phase of spinal shock, with complete urinary retention and areflexic detrusor. This shock phase lasted between 2 and 6 weeks. Sequential pressure studies of paraplegic dogs substantiated the clinical supposition that urinary retention during spinal shock phase is caused by an unresponsive detrusor. The sphincteric mechanism could be the implicated as an etiologic agent. Return of detrusor reflex activity was observed in all animals.

Studies on vesicourethral reflexes. I. Urethral sphincteric responses to detrusor stretch

For the purpose of studies on vesicourethral reflexes, a model was established wherein the vesicosphincteric unit is divided into two separate compartments. In one group, the compartments were formed by single mucosal separation but muscular continuity was maintained. In the other, complete interruption of muscular continuity was performed by full bladder wall thickness separation. To maintain the proper nerve and blood supply to the upper compartment, the separation was made below the ureteral orifices and urinary diversion was accomplished through ureterosigmoidostomy. Postoperative cystographic studies demonstrated the complete separation. Detailed pre- and postoperative physiologic studies were done. Spontaneous contraction of the upper compartment excited contraction of the detrusor component of the lower compartment where muscular continuity was maintained. Contraction of the upper compartment induced reflex relaxation of the sphincteric element, regardless of whether the muscular continuity was maintained or interrupted. Flaxedil and Regitine both led to a drop in resting urethral pressure and abolished the drop in urethral pressure in response to contraction of the upper detrusor compartment. Although muscular contraction might be a contributory factor, it is clear that a nerve-mediated spinal reflex exists that induces drop in urethral resistance in response to detrusor contraction.

Complete external sphincterotomy: correlation between endoscopic observation and the anatomic sphincter

Longitudinal cuts of various lengths and depths were made in the area of the external urethral sphincter in 18 male cadavers. The Iglesias resectoscope and the Collings knife electrode were used. Histologic sections of the prostate and of the membranous and bulbous urethra demonstrated that a cut of 2 cm. in length beginning from the verumontanum and 6 mm. in depth was necessary to completely incise the external urethral fibers. This procedure, when performed according to these criteria, effectively decreases urethral resistance, permits adequate bladder emptying and probably eliminates the need for a catheter.

Myelomeningocele. Part III. Urologic considerations

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