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Publications (13)42.65 Total impact

  • Article: Multi-institutional experience with PIC cystography--incidence of occult vesicoureteral reflux in children with febrile urinary tract infections.
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    ABSTRACT: It has been reported that all children with febrile urinary tract infections (FUTIs) and normal voiding cystourethrogram (VCUG) findings show occult reflux (vesicoureteral reflux [VUR]) when examined by cystography performed with positioning of the instillation of contrast at the ureteral orifice (PIC cystography). In this study, we evaluated the reproducibility of this finding using a prospective multi-institutional collaborative examination to determine whether PIC-VUR is as common in such cases as previously shown. From March 2002 to October 2003, four institutions performed PIC cystography consecutively and prospectively in pediatric cases of FUTI (greater than 101 degrees F) who had not shown VUR by conventional VCUG. We correlated the ureteral orifice (UO) configuration and position with the status of PIC-VUR. PIC cystography was performed in 39 children (31 girls and 8 boys; 75 FUTIs). We identified PIC-VUR in 32 (82%) of 39 children, involving 58 (74%) of 78 ureters. The likelihood of demonstrating PIC-VUR was increased 37-fold if the UO showed a patulous configuration and was increased 9-fold if the UO showed a lateral configuration. PIC-VUR was noted uniformly in UOs showing hydrodistension. This multi-institutional registry showed that the incidence of PIC-VUR (82%) in children with FUTI and normal standard VCUG findings is similar to that previously reported. We consider that PIC-VUR likely accounts for the FUTIs.
    Urology 04/2006; 67(3):608-11. · 2.43 Impact Factor
  • Article: Results of 265 consecutive proximal hypospadias repairs using the Thiersch-Duplay principle.
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    ABSTRACT: We review the evolution of the concept of tubularization of the urethral plate and our results in the repair of proximal hypospadias. A total of 281 children born with proximal hypospadias underwent Thiersch-Duplay urethroplasty with or without a midline incision of the urethral plate between 1989 and 1998. Followup data were available in 265 children. Excellent functional and cosmetic results were achieved in 88.7% of the patients. The use of either a dartos or tunica vaginalis flap to waterproof the urethral suture line resulted in a decrease in the fistula rate from 17% to 1.8%. The principles of Thiersch-Duplay urethroplasty represent the basic foundation for surgical techniques that use the urethral plate to construct a urethral tube. The use of this principle in the repair of proximal hypospadias compares favorably with other methods.
    The Journal of Urology 12/2004; 172(6 Pt 1):2382-3. · 3.75 Impact Factor
  • Article: Prevention of renal fibrosis by spironolactone in mice with complete unilateral ureteral obstruction.
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    ABSTRACT: Recent data suggest that aldosterone directly mediates cardiac fibrosis and hypertensive nephrosclerosis. We conducted experiments to determine whether administration of spironolactone, a mineralocorticoid receptor antagonist, reduced renal fibrosis in an experimental model of obstructive uropathy. Complete unilateral ureteral obstruction (UUO) was created surgically in 8 to 10-week-old male C57BL/6 mice by placing sutures around the right ureter. Spironolactone (50 mg/kg/daily) or 1% dimethyl sulfoxide vehicle was administered by subcutaneous injection for 1 to 2 weeks, and renal fibrosis was assessed by measuring trichrome staining and type I collagen deposition in the kidney. UUO lasting 1 week was associated with minimal parenchymal damage and spironolactone had no demonstrable effect. In contrast, administration of the mineralocorticoid antagonist (8 mice) for a 2-week period significantly reduced renal fibrosis in the obstructed kidney, compared to mice given the dimethyl sulfoxide vehicle (9). The beneficial effect of spironolactone treatment was not associated with any changes in serum potassium or aldosterone concentration, or urinary concentrations of sodium or potassium. Administration of spironolactone reduced renal fibrosis in mice with UUO. These findings suggest that clinical trials are warranted to determine the efficacy of aldosterone antagonists in conjunction with angiotensin converting enzyme inhibitors and/or angiotensin receptor blockers as renoprotective agents in patients with obstructive uropathy.
    The Journal of Urology 11/2004; 172(4 Pt 2):1590-4. · 3.75 Impact Factor
  • Article: Infectious response to E. coli: molecular and genetic pathways.
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    ABSTRACT: Urinary tract infections are most commonly caused by type 1-piliated Escherichia coli (UPEC) and result in urothelial apoptosis, local cytokine release and neutrophil infiltration. A human urothelial cell line was incubated with various E. coli isolates and was then characterized by flow cytometry. UPEC induced rapid urothelial apoptosis that was dependent upon interactions mediated by type 1 pili. Laboratory isolates expressing type 1 pili-induced approximately 50% less apoptosis. UPEC blocked activity of a NF-kappaB-dependent reporter in response to inflammatory stimuli by stabilizing IkappaBalpha and UPEC rapidly altered cellular signalling pathways. Finally, blocking NF-kappaB activity increased the level of the laboratory strain-induced apoptosis to the level of apoptosis induced by UPEC. These results suggest that UPEC blocks NF-kappaB and enhances type 1 pili-induced apoptosis as a component of the uropathogenic programme.
    International Journal of Antimicrobial Agents 10/2004; 24 Suppl 1:S57-60. · 4.13 Impact Factor
  • Article: Efficacy and safety of the Healthtronics LithoTron lithotripter.
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    ABSTRACT: To evaluate our experience with the LithoTron lithotripter (Healthtronics, Atlanta, GA), a dry portable system that utilizes a spark-gap electrode as an energy source. We prospectively evaluated the first 312 treatments performed on 199 men and 99 women with an average age of 43.5 years (range 4 months-80 years), over a 25-month period between May 1999 and June 2001. Of the 468 stones treated, 136 were located in the ureter, 52 in the renal pelvis or ureteropelvic junction, and 230 in the kidney; the sites of 50 were not specified in our database. The average stone size was 8.0 mm (range 1-40 mm). Follow-up included a plain (KUB) film, CT scan, or intravenous urogram (IVU) and was available for 256 patients. "Stone free" was defined as no fragments visible on postoperative images. The mean radiographic follow-up was 74 days (range 0-866 days). Data collection was initially done manually by data sheets, but a Web-based medical database application was developed in order to enter, store, retrieve, and analyze the data more efficiently. The average number of shocks delivered per renal unit was 2689 at 25.8 kV. Seventy-five percent of the procedures were performed with intravenous sedation. Two thirds (169/256) of the patients were rendered stone free with one treatment. According to size, 71% (209/294) of stones <1 cm, 57% (39/68) of stones between 1.0 and 1.5 cm, and 22% (8/36) of stones >1.5 cm were eliminated. There were 23 patients who required further treatment; from the available data, 18 of them are currently stone free. Perioperative complications occurred in 6 patients (2%). No patient had worsening renal function or new-onset hypertension. The effectiveness quotient was 59.3%. The LithoTron lithotripter is satisfactory for stones <1 cm.
    Journal of Endourology 02/2004; 18(1):1-5. · 1.85 Impact Factor
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    Article: Single layered small intestinal submucosa in the repair of severe chordee and complicated hypospadias.
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    ABSTRACT: Severe ventral chordee often accompanies proximal hypospadias. We describe our experience with single layered small intestinal submucosa (SIS), a commercially available, acellular, collagen based biomaterial, in the repair of severe chordee as part of a multistage approach to the repair of proximal hypospadias. Between 2001 and 2002, 9 boys with proximal hypospadias (penoscrotal to perineal) and severe ventral chordee (greater than 40 degrees) underwent SIS grafting to correct the curvature. In each case the urethral plate was transected at the point of maximal curvature, the defect in the corporal bodies was measured, and the SIS graft was cut 2 mm wider around the perimeter of the defect and sutured into place. Skin resurfacing of the ventral penis was performed in standard fashion using Byars flaps. Recurrence of chordee was assessed by an artificial penile erection test at the time of stage 2 reconstruction. Of the 9 boys 8 underwent a planned 2-stage repair with subsequent urethroplasty 6 to 12 months after the initial stage 1 chordee repair. Median age at stage 1 repair of the 8 boys was 9 months. Native meatus location was penoscrotal in 6 boys, mid scrotal in 1 and perineal in 1. A 14 month-old boy underwent 1-stage chordee correction with SIS and a transverse preputial island tube graft urethroplasty for penoscrotal hypospadias. There were no perioperative medical or surgical complications related to use of SIS for chordee repair. Median age of the 8 boys at stage 2 repair was 18 months. At stage 2 the graft site was supple and smooth without significant scarring. All chordee correction has remained durable with followup ranging from 16 to 21 months. Postoperative complications occurred in 3 cases, including meatal stenosis requiring meatoplasty, subcoronal fistula requiring repair and complete breakdown of the neourethra in the single stage repair case. Although this study includes a small population of patients and has limited followup, our favorable experience with single layer SIS suggests that it is a safe and effective, commercially available material for corporal body grafting to correct severe chordee as part of a multistage surgical approach to repair complex hypospadias. A larger series of patients with longer followup is necessary to determine if the chordee correction remains durable. Our experience is insufficient to judge its efficacy in single stage repairs.
    The Journal of Urology 11/2003; 170(4 Pt 2):1593-5; disussion 1595. · 3.75 Impact Factor
  • Article: Chylous ascites following surgical treatment for wilms tumor.
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    ABSTRACT: Postoperative chylous ascites is a rare complication of retroperitoneal surgery that has considerable morbidity. We review the pathogenesis and management of chylous ascites following surgical treatment of Wilms tumor. We identified 9 children with chylous ascites after surgical treatment of Wilms tumor. Of these cases 3 were treated at a single institution during the last 20 years and 6 were identified during retrospective chart reviews of patients enrolled in National Wilms Tumor Studies 3 and 4 to identify surgical complications. Chylous ascites presented as increased abdominal girth and poor feeding. Paracentesis or laparotomy was diagnostic. Patient age at presentation with Wilms tumor ranged from 6 to 95 months (median 15). Left nephrectomy was performed in 5 cases, right nephrectomy in 3, and left nephrectomy and partial right nephrectomy in 1 with bilateral disease. Lymphadenectomy including the hilar and periaortic lymph nodes was performed in 5 patients, 4 of whom also underwent some form of suprahilar lymph node dissection. Three patients underwent lymph node sampling of the hilar, periaortic and some suprahilar lymph nodes. All children received adjuvant chemotherapy and 4 were treated with adjuvant irradiation to the surgical bed before the diagnosis of chylous ascites. The interval between surgery and diagnosis of ascites ranged from 12 to 49 days (median 21). Of the patients 7 were successfully treated with conservative measures, total parenteral nutrition and/or a diet containing primarily medium chain triglycerides, and 2 required invasive procedures, including exploratory laparotomy and ligation of disrupted lymphatic vessels or placement of a peritoneovenous shunt. Extensive lymph node dissection, particularly above the level of the renal hilum, appears to be associated with the development of postoperative chylous ascites. The National Wilms Tumor Study guidelines do not require formal lymph node dissection for staging and only lymph node sampling is recommended. Elimination of formal lymphadenectomy along with meticulous ligation of lymphatics should decrease the incidence of this complication. Fortunately, conservative treatment with total parenteral nutrition and/or medium chain triglycerides will remedy the problem in the majority of children.
    The Journal of Urology 11/2003; 170(4 Pt 2):1667-9; discussion 1669. · 3.75 Impact Factor
  • Article: The role of gadolinium enhanced magnetic resonance imaging for children with suspected acute pyelonephritis.
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    ABSTRACT: The diagnosis of pyelonephritis is primarily clinical. However, the history and physical findings can be confusing in children, leading to adjunctive nuclear renal cortical scintigraphic studies (99mtechnetium dimercapto-succinic acid [DMSA]) to confirm the diagnosis. Nonetheless, ambiguity occurs when differentiating between acute pyelonephritis and chronic scarring. We report our initial experience with gadolinium enhanced inversion recovery magnetic resonance imaging (MRI) to diagnose acute pyelonephritis. Nine patients 7 months to 18 years old (mean age 81 months) underwent MRI to confirm radiographically a clinical suspicion of acute pyelonephritis. All patients had at least 1 prior episode of clinical pyelonephritis. Data were collected to determine whether acute pyelonephritic changes could be differentiated from chronic pyelonephritis on the basis of MRI characteristics. Of the 9 patients 4 were identified as having acute pyelonephritis on MRI (persistently high signal intensity after gadolinium), 2 demonstrated evidence of postpyelonephritic scar (parenchymal loss without change in signal intensity), 1 had evidence of acute pyelonephritis and chronic changes, and 2 had a completely normal examination (decreased signal intensity after gadolinium). At our institution the billable cost of MRI to the patient is $1,329, while the billable cost of 99mtechnetium DMSA is $1,459. All patients younger than 6 years required intravenous sedation for MRI, whereas 70% of those younger than 6 years require intravenous sedation for DMSA scanning at our institution. MRI provided greater anatomical detail regarding the renal architecture without radiation exposure, and allowed the unambiguous diagnosis of acute versus chronic pyelonephritis scar in a 1-time (versus often multipart for DMSA) imaging study. In cases where adjunctive imaging studies are useful to make a diagnosis gadolinium enhanced inversion recovery magnetic resonance imaging allows the detection of acute pyelonephritis rapidly, cost-effectively and safely in the pediatric population.
    The Journal of Urology 07/2003; 169(6):2308-11. · 3.75 Impact Factor
  • Article: Modified cecal flap neoappendix for the Malone antegrade continence enema procedure: a novel technique.
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    ABSTRACT: We report our experience with the creation of a tubularized cecal flap to construct a neoappendix. This flap effectively serves as an alternative means of creating a conduit for antegrade continence enemas in patients who have either an absent or an unusable appendix. We reviewed our results from our initial 4 patients in whom we used this technique. A neoappendix is created from a medially based flap of distal cecum that is tubularized over a catheter and then buried in a seromuscular tunnel to create an antireflux mechanism. A skin stoma is then created. All stomas are continent, functional and without any evidence of stenosis or necrosis of the cecal flap with followup ranging from 3 months to 8 years. A medially based cecal flap neoappendix is an easily created and reliable conduit for antegrade enemas. This procedure should be considered within the surgical armamentarium of urologists and pediatric surgeons when the appendix is absent, atretic or fibrotic.
    The Journal of Urology 07/2003; 169(6):2321-4. · 3.75 Impact Factor
  • Article: Foley catheter removal techniques.
    Adam C Weiser, Richard I Silver
    Urology 02/2003; 61(1):257; author reply 257. · 2.43 Impact Factor
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    Article: Metachronous presentation of ureterovesical junction obstruction contralateral to a multicystic dysplastic kidney.
    The Journal of Urology 07/2002; 167(6):2538-9. · 3.75 Impact Factor
  • Article: Percutaneous hepatolithotomy: the Northwestern University experience.
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    ABSTRACT: Obstruction of intrahepatic ducts by calculi can lead to abdominal pain, cholestasis, abscesses, and cholangitis. Patients with stones recalcitrant to extraction using endoscopic retrograde cholangiopancreatography (ERCP) have traditionally been referred to a general surgeon for open stone extraction or hepatic lobectomy despite its great potential morbidity. Borrowing techniques, instrumentation, and experience in performing percutaneous nephrolithotomy, we describe our experience with percutaneous hepatolithotomy (PHL), a minimally invasive, safe, and effective alternative to open surgery for recalcitrant biliary stones.
    Journal of Endourology 07/2002; 16(5):293-7. · 1.85 Impact Factor
  • Article: Extracorporeal shock wave lithotripsy of pancreatic duct stones using the Healthtronics LithoTron lithotriptor and the Dornier HM3 lithotripsy machine.
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    ABSTRACT: Pancreatic duct stones, which are most often a result of alcohol induced chronic pancreatitis, can lead to chronic abdominal pain, pseudocysts, and exocrine and endocrine failure of the pancreas. Others have reported success using extracorporeal shock wave lithotripsy (ESWL) (Dornier Medical Systems, Inc., Marietta, Georgia) for pancreatic stones. We report our experience with pancreatic ESWL using the LithoTron (Healthtronics, Marietta, Georgia) and HM3 (Dornier) lithotripsy machines. We performed pancreatic ESWL in 23 patients in 4 years, including in 12 with the LithoTron and in 11 with the HM3. After ESWL endoscopic retrograde cholangio-pancreatography (ERCP) was performed in all cases. Stone-free status was defined as no stone fragments visualized or the elimination of all post-ESWL stones by ERCP. Stone-free status was documented in 83% and 82% of patients treated with the LithoTron and HM3, respectively, and 2 per group later required open surgical intervention. There were no changes in pancreatic enzymes and no cases of sepsis or fever after ERCP. In association with post-procedure ERCP pancreatic ESWL is an effective and safe procedure that enables patients with obstructing pancreatic duct stones recalcitrant to primary endoscopic extraction to avoid a potentially morbid open procedure. The HM3 and LithoTron have comparable efficacy and safety. This modality is particularly effective for a stone aggregate of less than 20 mm., while a larger stone burden of greater than 20 mm. in aggregate and multiple stones are clear risk factors for treatment failure.
    The Journal of Urology 03/2002; 167(2 Pt 1):485-7. · 3.75 Impact Factor