[Applications of robotic surgery in pediatric urology. Description of the technical principles]. / Aplicaciones de la cirugía robótica en urología pediátrica. Descripción de los principios técnicos.

The incorporation of the robotic surgery to the pediatric urology permits less invasive and more precise therapeutic alternatives for the patient. It corrects some limitations of laparoscopic surgery, with its 3 dimensional vision, accurate movements without tremor, and more degrees of freedom, allows an ergonomic position to the surgeon and has a shorter learning curve. Different procedures were performed with da Vinci surgical system, in a secure and effective way, as pyeloplasty, total or partial nephrectomy, orchidopexy, intra or extravesical ureteral reimplant, enterocystoplasty, Mitrofanoff and others. These techniques and their outcomes will be reviewed, as well as some of the challenges still posed by this methodology.

Clean, intermittent catheterization of infants with neurogenic bladder.

Clean, intermittent catheterization was instituted in 38 babies with myelodysplasia who were thought to be at risk for upper urinary tract deterioration because of neurogenic bladder dysfunction. There were 19 patients 2 weeks to 12 months of age, 11 were 1 to 2 years of age, and 8 were older than 2 years. Effectiveness of clean, intermittent catheterization was determined by maintenance of upper urinary tract stability. Upper urinary tracts improved or remained stable in 13 of 16 infants (81%) with reflux and 16 of 18 infants (89%) with detrusor-sphincter dyssynergia. Bacteriuria was present in 16 (42%), with only 2 infants (5%) having a febrile episode; no infant required hospitalization because of urinary tract infections. No further complications were identified in infants who were cleanly and intermittently catheterized. Most families found clean, intermittent catheterization of their infants easy to master and not stressful, and their children adjusted to it at an early age.

Paraurethral cysts in female neonate.

Paraurethral cysts in the female neonate are uncommon lesions. All reported cases have either ruptured spontaneously or responded to simple marsupialization. However, complete urologic evaluation is mandatory because they simulate ectopic ureteroceles in appearance. Herein is reported our experience with 5 patients. The etiology, embryogenesis, natural history, differential diagnosis, and treatment are discussed.

Megaureters in children.

The results of surgery for megaureter are reviewed in 40 children. Special attention is focused on the etiologic causes of these dilated ureters in relation to the surgical results. Thirty of 31 children with obstructive or refluxing megaureters and normal bladders had satisfactory results. Less satisfactory results occurred in children with abnormal bladder dynamics. No child in this series required upper ureteral tapering. A discussion of the causes and further management of the surgical failures is presented.

Use of a catheter limiter during intermittent catheterization.

We report on the use of a new device, the catheter limiter, to facilitate clean intermittent catheterization. The device limits the length of catheter entering the urethra. This provides a means to reduce the risk of mechanical injury and perforation, minimizes incomplete emptying, and improves safety and patient acceptance of intermittent catheterization.

Balloon-wire retrieval of a migrated urethral stent in the early postoperative period.

We report on a new endoscopic approach to the removal of a migrated urethral stent following hypospadias repair. A flexible balloon-tipped guide wire allows the effective cystoscopic retrieval of a urethral stent, suggesting potential applications to the removal of other foreign bodies in the urinary tract.

Urachal anomalies: defining the best diagnostic modality.

OBJECTIVES: Urachal abnormalities are uncommon and the literature is primarily comprised of case reports. Conclusions regarding the presentation and diagnosis of these abnormalities may be elucidated by reviewing a large experience. METHODS: The records of 45 patients with urachal abnormalities in the pediatric age group were reviewed from 1970 to 1997. This included 24 boys and 21 girls with an age range from 1 day to 20 years (average 4.0 years). The presenting complaint was periumbilical discharge in 19 patients (42%), umbilical cyst or mass in 15 (33%), abdominal or periumbilical pain in 10 (22%), and dysuria in 1 (2%). The diagnosis consisted of a urachal sinus in 22 children (49%), a urachal cyst in 16 (36%), and a patent urachus in 7 (15%). Various radiographic studies were used to establish the diagnosis. RESULTS: Patients with a urachal sinus had 16 voiding cystourethrograms performed (only 1 diagnostic), 9 sinograms (all diagnostic), 8 ultrasounds (4 diagnostic), and 1 excretory urogram (normal). Those with a urachal cyst had 8 voiding cystourethrograms (1 diagnostic), 5 excretory urograms (all normal), 4 ultrasounds (all diagnostic), and 1 computed tomography scan (diagnostic). Children with a patent urachus had 2 excretory urograms (both diagnostic), 1 voiding cystourethrogram (diagnostic), and 2 ultrasounds (normal). One baby with a patent urachus was diagnosed prenatally during ultrasound screening. The diagnosis was made by history and physical examination alone in 5 children and at the time of surgery in 1. Treatment consisted of surgical excision of the urachal abnormality with a cuff of bladder in 22 children, surgical excision without a bladder cuff in 22, incision and drainage of a urachal cyst (1%), and laparoscopic excision of a patent urachus with a bladder cuff in another (1%). There were three wound infections postoperatively. None developed any long-term sequelae. CONCLUSIONS: The diagnosis of urachal abnormalities can be made with certainty if a good physical examination and the appropriate radiographic test are performed. A patient who presents with periumbilical drainage should have a sinogram performed, which should be diagnostic for both a urachal sinus and a patent urachus. Any child who presents with a periumbilical mass should have an ultrasound performed, which should be diagnostic for a urachal cyst.

Urodynamic evaluation of boy with myelodysplasia and incontinence.

Twenty-two boys with myelodysplasia and incontinence were evaluated urodynamically. Three types of bladder function were noted, but each could not be correlated with any particular neuroligic level. The integrity of the external sphincter innervation was determined by electomyographic monitoring of periurethral striated muscle. Bladder sphincter dyssynergia was found in one of the boys with voluntary control, five with involuntary bladder contractions, and five with adynamic bladders who voided by Credé's method. A radiologically narrow external sphincter on voiding cystography could only be correlated with the bioelectric activity in children with dyssynergia. A narrow sphincter was also noted in three children with synergy and four with complete lower motor neuron lesions. Marked fibrosis was found to be the cause of narrowing of external sphincter area in these boys. Thus, urodynamic evaluation helped define the etiology of outlet obstruction when it was present in the boy with myelodysplasia. A classification of bladder sphincter function is proposed.

Dilemma of small pyelonephritic kidney associated with vesicoureteral reflux.

Nineteen children with severe unilateral pyelonephritic scarring secondary to reflux and infection were followed up for at least five years after ureteral reimplantation. The small kidneys in these children grew at a rate which paralleled expected normal, and this growth was independent of the degree of hypertrophy in the contralateral kidney or the size difference between each pair of renal units. The authors differentiate between obligate and compensatory renal growth and conclude that children with a small pyelonephritic kidney should undergo reimplantation rather than nephrectomy because of the recuperative powers of the growing kidney and its ability to become a potentially life-sustaining organ in the future.

Evaluation and management of children with sacral agenesis.

Sacral agenesis is a rare congenital anomaly of the lower vertebral column which usually produces lower urinary tract dysfunction. Sixteen children with varying degrees of sacral agenesis and urinary symptoms were extensively evaluated. The neurologic lesion varied from no denervation to a complete loss of sacral motor and sensory function. The treatment instituted was individualized and based on specific urodynamic and radiologic findings. Overall, 12 of the 16 children (75%) achieved continence. Clues to the diagnosis including symptoms, physical findings, and the relationship to maternal diabetes are discussed.

Congenital posterior urethral perineal fistulae: a unique form of urethral duplication.

Three unique cases of urethral duplication, often referred to as congenital posterior urethral perineal fistulae, are presented. Presenting signs and symptoms, evaluation, and treatment are discussed, and the literature is reviewed. Although labeled as a fistula in the literature, this entity most likely represents a distinct type of urethral duplication. A functional dorsal urethra separates it from the other forms of urethral duplication.

The Mitrofanoff principle in continent urinary reconstruction.

Continent urinary diversion has increasingly become important for treating children and adults with urinary tract pathology that cannot be managed by direct reconstructive techniques. The Mitrofanoff principle, a term that has become synonymous with the flap valve mechanism for promoting the unidirectorial flow of a fluid medium, is a recapitulation of nature's design for the competent ureterovesical junction. Construction of a catheterizable channel using this principle can be performed with a variety of tissues and serves well as a continence mechanism for either the native bladder or intestinal reservoirs. In addition to its utility in managing urinary incontinence, implantation of a catheterizable channel into the cecum can be used to manage fecal incontinence in patients with neurogenic bowel dysfunction.

Management of the dilated obstructed ureter.

Megaureters have been classified as refluxing, obstructed, nonrefluxing-nonobstructed, and refluxing-obstructed. The recommendations for the management of each type are fairly well agreed on. Where controversy has arisen is in the differentiation of the types, especially the primary obstructed from the nonrefluxing-nonobstructed. Distinguishing dilatations that represent significant obstruction from those that apparently are anatomic variants having no detrimental implications for renal function is no simple task, especially in the neonatal infant.

Current trends in hypospadias repair.

There is no single, universally applicable technique for hypospadias repair. Command of a technically straightforward repair with few complications and proven success and versatility in a reasonable range of hypospadias defects are desired goals. Several well-established techniques exist for the repair of all hypospadias defects. The Snodgrass tubularized incised plate urethroplasty, a recent contribution with exemplary early results, has become a popular technique for primary and preoperative repair of middle and anterior hypospadias. Other innovative modifications, and technical advances, such as the use of laser and tissue solder, continue to emerge. With time, these may herald improvements to even the most basic of sound principles involved in all hypospadias repair.

Complications of hypospadias repair.

Hypospadias is one of the more common and one of the most challenging problems in urologic surgery. The past two decades have ushered in an era of new operations and variations of older ones, which, when coupled with technical advancements and improvements in management, have redefined the aims of the surgeon, who now strives to create a "normal" penis with a minimum of complications. Minimization of complications is contingent on selection of an operation properly tailored to the individual's anatomy. To this end, the surgeon's armamentarium must include a variety of repairs and familiarity with the limitations and potential complications inherent in each. After describing the principles of surgical selection, technique, and postoperative management used in our institution, this article deals primarily with the avoidance and management of the immediate and long-term complications of hypospadias surgery.

Current concepts in the perinatal diagnosis and management of hydronephrosis.

Perinatal urology has become a significant facet of pediatric urologic practice. This article reviews the approaches to the diagnosis of prenatal hydronephrosis and its typical sonographic appearances in relation to the underlying pathology. A review of the outcomes of prenatal uropathology serves as a basis on which to interpret reports of prenatal intervention for hydronephrosis. A critical review of the experience of prenatal intervention is conditionally supportive of its benefits, but this view must be tempered by a recognition of the inherent risk to the mother and fetus. Included within this view is a recognition that not all hydronephrosis is caused by obstruction. More specific prognostic indicators of renal and pulmonary functional reserve are critically needed to permit appropriate patient selection. This must be coupled with more rigorous assessment of outcomes and complete reporting of the results. Continued basic and clinical research is important in developing these data. A management strategy for hydronephrosis in the prenatal and postnatal periods is presented, based on the goal of permitting maximal renal as well as pulmonary development in utero and in the newborn period.

Complications of urinary tract undiversion.

The complications of urinary tract undiversion can be divided into those associated with patient selection, choice of techniques, and early and late surgical difficulties. Patient selection must take into account the original reason for diversion (incontinence, hydronephrosis, reflux, or renal functional impairment), current renal function and bladder dynamics, upper urinary tract anatomy, and psychosocial considerations. Technical considerations require versatility and ingenuity on the part of the surgeon. Although direct uroepithelium-to-uroepithelium continuity is ideal, this often cannot be accomplished. A variety of techniques including transureteroureterostomy, psoas hitch of the bladder, bladder augmentation, ileocecal and colon interposition, and autotransplantation can be used to facilitate the refunctionalization of the urinary tract. One must monitor the patient postoperatively for potential early and late complications. Meticulous attention to surgical details will help minimize these. The ultimate goal is to achieve stable renal function and urinary continence.

Ureteropelvic junction obstruction in children.

The spectrum of problems inherent in the diagnosis and treatment of ureteropelvic junction obstruction is outlined on the basis of the review of a series of 195 children.

Pathophysiology and recoverability of function and structure in obstructed kidneys.

This article focuses on the effect of obstruction on renal structure and function and the assessment of the degree of recovery following relief of the obstruction.

The unstable bladder in childhood.

A comprehensive study of children with voiding dysfunction, which included careful documentation of voiding habits, thorough radiologic investigation, and urodynamic evaluation was undertaken. Proposed etiologic factors, indications for therapy, and results of treatment are discussed.