Design, implementation and evaluation of a new core learning objectives curriculum for a urology clerkship.

PURPOSE: Until recently, medical students at the University of Wisconsin School of Medicine and Public Health participated in a traditional 2-week urology clerkship. We hypothesized that a new curriculum with core learning objectives and student oriented didactic sessions would increase learning and satisfaction compared to a traditional clerkship. MATERIALS AND METHODS: Between July 2008 and June 2009, 55 medical students completed the urology clerkship following the traditional curriculum. Between July 2009 and June 2010, 51 students followed the core learning objectives curriculum. We compared the curriculum outcomes using objective and subjective measures. Overall student participation was 90%, with 95 of 106 students completing both assessment tools. RESULTS: The objective scores of the students following the core learning objectives were higher than those of the students following the traditional curriculum. The t test to evaluate the difference between the 2 curricula was statistically significant (t = 2.845, df = 93, p <0.05). Subjective scores for the core learning objectives group were lower in all but 1 category. Student perception of knowledge attainment for the core learning objectives cohort was higher than that of the traditional cohort, but none of the subjective scores was statistically significant. CONCLUSIONS: This study demonstrated that a core learning objectives curriculum was associated with higher objective test scores compared to a traditional model, suggesting that the core learning objectives curriculum increased student learning compared to the traditional curriculum. However, the core learning objectives cohort did not show greater satisfaction than students following the traditional curriculum.

Electrically stimulated detrusor myoplasty.

PURPOSE: Many children with spina bifida and other causes of neurogenic bladder rely on clean intermittent catheterization to empty the hyporeflexic or areflexic bladder. Direct bladder and sacral nerve root stimulation have been met with limited success. We studied the electrical stimulation of a rectus abdominis muscle flap wrapped around the bladder to achieve bladder contractility and emptying. MATERIALS AND METHODS: The feasibility of performing rectus detrusor myoplasty in humans was first studied in 8 cadavers. In male and female cadavers it was possible to wrap the distended bladder completely with the rectus abdominis muscle. The rectus abdominis muscle was surgically dissected with preservation of its insertion on the pubis bone and rotation of its mid section behind the bladder to effect a complete bladder wrap. The deep inferior epigastric artery and veins, and 2 most caudal intercostal nerves were preserved. This unilateral rectus abdominis muscle flap was then electrically stimulated with 2 pairs of bipolar electrodes inserted into the muscle near the nerve entrance. Stimulation frequencies of 40, 60 and 80 Hz. were used in each of the 8 dogs. The increase in intravesical pressure over baseline, compliance and post-void residual were measured. Paired Student's t tests were used for statistical comparisons. RESULTS: The increase in intravesical pressure ranged 35 +/- 5 to 45 +/- 7 cm. H2O at stimulation frequency 40 and 80 Hz., respectively. Post-void residual was 27 +/- 4%, 22 +/- 3% and 26 +/- 3% at stimulation frequencies 40, 60 and 80 Hz., respectively. Intravesical pressure was significantly increased over baseline bladder pressure (p <0.05). CONCLUSIONS: Electrically stimulated detrusor myoplasty results in uniform increases in intravesical pressure and reasonable bladder emptying in an animal model. We are currently investigating detrusor myoplasty in a chronic study to determine whether it can be used for enhanced bladder emptying in children with poor detrusor contractility.

A prospective randomized trial of dressings versus no dressings for hypospadias repair.

PURPOSE: Dressings following hypospadias repair have the benefits of gentle compression for hemostasis, immobilization of the wound and formation of a "hermetic seal." Potential disadvantages include producing ischemia, infection and pain during dressing removal. We compare the success and complications of hypospadias repair with and without dressings in a prospective randomized manner. MATERIALS AND METHODS: Children with hypospadias were randomized either to receive or not receive a transparent film dressing for 2 days. A written informed consent was obtained. Hypospadias repair was performed in 100 consecutive patients. Study exclusion criteria were known coagulopathy and oozing at the end of the case. Criteria for success were a glanular meatus, single forward directed stream, unimpeded voiding, absence of penile chordee, good cosmesis and no need for any secondary procedure. All but 1 hypospadias repair preserved the integrity of the urethral plate. Statistical significance was considered at p <0.05. RESULTS: We were able to randomize between the dressed and nondressed groups based on fresh versus redo cases, position of the urethral meatus, severity of chordee, use of epinephrine, duration of surgery, type of repair and chordee correction (p >0.05). Of 49 patients 44 (90%) had successful results in the dressed and nondressed groups. Postoperative calls were more common in the undressed group (p = 0.02) but no particular complication was more common in either group (p >0.05). Mean followup was 1 year, and there was no clinical or statistical difference between the dressed and nondressed groups with regard to success of the operation (p >0.05). CONCLUSIONS: The success rate for hypospadias surgery that preserves the urethral plate is independent of dressing usage. Dressings may not be indicated for all hypospadias repairs.

Treatment of distal ureteral stones in children: similarities to the american urological association guidelines in adults.

PURPOSE: The American Urological Association (AUA) published clinical guidelines for the treatment of ureteral calculi in adults and note that up to 98% of stones less than 5 mm. in diameter will pass spontaneously. Ureteroscopy and shock wave lithotripsy were acceptable treatment choices for stones less than 10 mm. in diameter in the distal ureter. We reviewed our management of distal ureteral stones in children to see if the AUA Guidelines for adults would apply. MATERIALS AND METHODS: A total of 14 males and 19 females with a mean age of 12 years (range 0.5 to 17) required hospitalization in the last 6 years for distal ureteral obstruction due to stones. Excretory urography or computerized tomography was performed in all cases, and mean stone size was 4 mm. (range 1 to 15). When stones did not pass spontaneously most patients were treated with ureteroscopic laser lithotripsy. RESULTS: There were 12 (36%) with a mean age of 11 years and a mean stone size of 2 mm. (range 1 to 3) who passed stones spontaneously with intravenous hydration and narcotics. No child passed a stone 4 mm. or greater spontaneously in this series. Of 21 patients (64%) with a mean age of 12 years and a mean stone size of 5 mm. (range 1 to 15) 2 were treated with ureteral stents, 17 with ureteroscopic lithotripsy and 2 with shock wave lithotripsy. All patients were stone-free at the end of the procedures. The stone composition was predominantly calcium oxalate. Mean followup was 2 years. CONCLUSIONS: Similar to the AUA guidelines in adults, most stones less than 3 mm. in diameter in the distal ureter of children will pass spontaneously. Stones 4 mm or greater in the distal ureter are likely to require endosurgical treatment. Ureteroscopy and shock wave lithrotripsy have a high success rate for stones between 4 and 15 mm. in the distal ureter. Needle ureteroscope and laser lithotripsy have allowed more stones to be treated safely and effectively in smaller children.

Approach to urinary diversion in the surgical patient.

Major surgical procedures may remove part or all of the bladder and make an incontinent or continent urinary diversion appropriate. Preoperative consideration must be given to 1) the stoma and its position, 2) the catheterizable channel, 3) the urinary continence mechanism, and 4) the substitute bladder reservoir. Complete bowel preparation and broad-spectrum antibiotics are desirable. The patient's motivation for taking care of a continent urinary diversion is important, since lifelong catheterization and mucous irrigation may be necessary. The status of the native bladder outlet and urinary sphincter is important in cases in which an orthotopic continent urinary diversion is considered. Preoperative evaluation by a stoma therapist is invaluable. Adequate urinary drainage is important in the immediate postoperative period. Patients with urinary diversions must be followed lifelong to rule out asymptomatic deterioration of their upper urinary tracts and to check for potential metabolic and nutritional problems.

Laparoscopic-assisted continent urinary diversion in obese patients.

BACKGROUND AND PURPOSE: The Pfannenstiel incision provides good access to the bladder and bladder neck for major reconstructive surgery in the thin patient, whereas a midline incision is often necessary to get adequate exposure in the obese patient. We describe our experience using laparoscopic-assisted continent urinary diversion in conjunction with other bladder and bladder neck surgery in obese patients. PATIENTS AND METHODS: Three female patients (mean age 18; mean weight 175 pounds) with neurogenic bladder underwent Mitrofanoff appendicovesicostomy continent urinary diversion to the umbilicus and pubovaginal sling. An umbilical port for the telescope and two lateral ports were used. Once the appendix and right hemicolon had been completely mobilized up to the hepatic flexure, reconstruction was completed through a low Pfannenstiel incision. RESULTS: There were no laparoscopic complications. None of the laparoscopic port sites was visible postoperatively, as one was in the base of the umbilicus, and the other two had been incorporated into the Pfannenstiel incision. With a mean follow-up of 1 year, all patients were continent and catheterizing their umbilicus easily. Pfannenstiel incisions were well healed, and the patients were quite satisfied with their cosmesis. CONCLUSION: Laparoscopic-assisted Mitrofanoff appendicovesicostomy continent urinary diversion to the umbilicus can be performed in conjunction with a Pfannenstiel incision to complete major bladder and bladder neck surgery in the obese patient with good postoperative cosmesis. This procedure represents a nice compromise between a very lengthy bladder reconstructive procedure done purely laparoscopically and a midline incision with good exposure but suboptimal cosmesis.

A large animal model of bladder exstrophy: observations of bladder smooth muscle and collagen content.

PURPOSE: The development of adequate bladder capacity is not ensured in all patients with bladder exstrophy despite successful bladder closure and reconstruction. To determine the factors leading to the development and maturation of the exstrophic bladder we created a large animal model of exstrophy. We compared biopsies obtained from a cohort of experimentally induced exstrophic neonatal sheep bladders to those of normal control bladders and related the findings to a previously reported comparison of human neonatal normal and exstrophic bladders. MATERIALS AND METHODS: Bladder specimens of 7 newborn lambs with experimentally induced exstrophy were compared to specimens of 10 newborn control lamb bladders. All specimens were stained with Masson's trichrome as well as with specific monoclonal antibodies to types I and III collagen. Stained sections were then analyzed using a morphometric image analysis system to quantify the amounts of smooth muscle and collagen present. RESULTS: A significant increase in the ratio of collagen-to-smooth muscle was noted in exstrophic versus normal control bladders (p <0.05). This difference was similar to that in the previous study of neonatal human bladders. There was no significant difference in the ratios of types I and III collagen in the 2 groups of sheep bladders. This finding is different from that reported in the previous human studies. CONCLUSIONS: Overall changes in the ratio of smooth muscle-to-collagen in the sheep exstrophy model are similar to those in humans. However, the differences in collagen types I and III do not seem to be present.

Feasibility of total intravesical endoscopic surgery using mini-instruments in a porcine model.

BACKGROUND AND OBJECTIVES: The aim of minimally invasive approaches to vesicoureteral reflux, such as endoscopic trigonoplasty, is to lower the morbidity of open procedures without compromising the results. Initial successes have not been sustained, mainly because of trigonal splitting, which results in the ureteral orifices returning to their preoperative positions. This study was designed to address trigonal splitting by mobilizing the ureters before repositioning them and to evaluate the feasibility of accomplishing this intravesically with 2- to 3-mm endoscopic mini-instruments. METHODS: Bilateral vesicoureteral reflux was surgically created in 10 minipigs. After radiologic confirmation of success 4 weeks later, modified trigonoplasty was performed by endoscopic intravesical mobilization of both ureters and incision of the trigonal mucosa using 2-mm instruments. The ureteral orifices were then advanced toward the midline and sutured in place. The initial surgical techniques were modified to permit the entire procedure to be performed endoscopically in the last four minipigs. Cystograms and intravenous urograms were obtained 4 weeks later. RESULTS: Two minipigs died postoperatively. Six of the remaining eight had persistent reflux, including three of the four in the group treated completely by endoscopic means. None of the dissected ureters showed evidence of stricture or necrosis. CONCLUSIONS: Although the procedure was not successful in correcting reflux in this model, this study demonstrates the feasibility of endoscopic ureteral mobilization. With current instrumentation, there is no significant technical obstacle to complete intravesical endoscopic surgery, including ureteral reimplantation.

Urologic management of congenital nephrotic syndrome of the Finnish type.

A 7-month-old girl with congenital nephrotic syndrome (CNS) of the Finnish type was referred to our group for surgical evaluation and recommendation of a treatment plan. A Medline literature search was conducted using data bases from 1980 to 1996, on the topics of "congenital nephrotic syndrome" and "surgery." Although there were several articles on CNS in the nephrology and pediatric journals, we found none in the urologic literature. Although a few medical centers advocate a less invasive unilateral nephrectomy or percutaneous renal ablation, most institutions still recommend bilateral nephrectomy to manage patients with CNS in whom aggressive medical management fails. Bilateral nephrectomy followed by dialysis and transplantation should remain the standard of care in 1997 for children with severe CNS.

The evaluation and treatment of prolonged hematuria in adolescents.

The causes of hematuria in children have not changed significantly during the past several decades. However, recent advances in endoscopic technology have allowed the pediatric urologist greater ability to evaluate and treat the child's source of hematuria. Close cooperation between urologist, nephrologist, and pediatrician should ensure that evaluation and management of these children is done in an efficient and definitive manner. Herein is reported the presentation and evaluation of an adolescent girl whose history is similar to other adolescents who have presented to our urologic department with a long history of painless, gross hematuria. We suggest that patients whose clinical presentation is similar to this child's be evaluated with renal and bladder ultrasound, intravenous urography, and when necessary, cystoscopy and ureteroscopy for treatment of their hematuria.

Diagnostic evaluation and management of the child with ambiguous genitalia.

When it is first noted in the newborn nursery that a child is born with ambiguous genitalia, it can be very upsetting and confusing for parents, as well as challenging for pediatricians and nursing staff. In this article, I hope to clarify the rather complex topic of ambiguous genitalia and its various causes. I will also review normal genital development, as well as the medical and surgical management of the various forms of ambiguous genitalia.

Ureteral duplication with lower pole ectopia to the vas: a case report of an exception to the Weigert-Meyer law.

We report an unusual case of ureteral duplication with lower-pole ectopia and ureterolithiasis, which violates the Weigert-Meyer law. The duplicated ureter arose from a lower-pole calyx and drained inferiorly into the ipsilateral vas. A presentation of the case is followed by a comparison to the only known similar one, reported in 1988. A possible embryologic hypothesis for this anomaly is discussed.

Creation of a model of bladder exstrophy in the fetal lamb.

PURPOSE: To our knowledge we describe the first reproducible large animal model to mimic the congenital birth defect of classic bladder exstrophy. MATERIALS AND METHODS: Eight male and 15 female fetal sheep underwent in utero surgical creation of classic bladder exstrophy. The fetus was then replaced within the amniotic sac and allowed to come to term. A sham procedure was performed on 16 male fetuses. RESULTS: After the creation of bladder exstrophy 53% of the female and 62% of the male fetuses survived to full term and through delivery. Of the male fetuses that underwent sham surgery 62% also survived through delivery. Lambs with exstrophy were born with the bladder wall in continuity with the abdominal wall and exposed to the environment. The sham operated male lambs had a well healed abdominal scar. CONCLUSIONS. To our knowledge we have devised the first reproducible large animal:model of bladder exstrophy. This model will be useful in studying bladder development and composition in the patient with exstrophy. It may also serve as a useful tool in developing innovative forms of surgical treatment for such patients.

Expression of human B cell-associated antigens on leukemias and lymphomas: a model of human B cell differentiation.

A series of monoclonal antibodies that define B cell restricted and associated antigens was utilized in an attempt to characterize tumors of B lineage and to relate these tumors to B cell differentiative stages. Antigens that were previously shown to be B cell restricted on normal B lymphocytes were similarly expressed only on B cell malignancies. In contrast, antigens that were B cell associated were also found on tumors of other lineages. Moreover, on the basis of cell surface phenotypes, tumors of B cell origin were divided into three major subgroups, which corresponded to the level of differentiation of the malignant tumor cell: pre-B cell stage (non-T acute lymphoblastic leukemia and chronic myelocytic leukemia in lymphoid blast crisis); the mid-B cell stage (chronic lymphocytic leukemia, poorly differentiated lymphomas); and secretory B cell stage (large cell lymphomas and plasma cell tumors). A hypothetical model is derived that relates the malignant B cell to its normal cellular counterpart on the basis of cell surface expression of this panel of B cell-restricted and B cell-associated antigens.

Isolation and characterization of human B lymphocyte enriched populations. I. Purification of B cells by immune rosette depletion.

In the present study we describe a technique for the preparation of a highly purified B cell population from peripheral blood mononuclear cells (PBMC) by immune rosette depletion of non-B cells utilizing monoclonal antibodies directed at T cells, monocytes and null cells. The non-rosetted population contains greater than 90% B cells after a single rosetting step. The technique is simple, rapid and reproducible and results in minimal cell loss. In contrast, the E rosette negative (E-) fraction contains approximately 20% B cells whereas the surface immunoglobulin positive (sIg+ population obtained by Sephadex-anti-F(ab')2 column chromatography is comprised of approximately 60-80% B cells.