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Dive into the research topics where Lars J. Cisek is active.

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Featured researches published by Lars J. Cisek.


BJUI | 2001

A multi-institutional analysis of laparoscopic orchidopexy

Linda A. Baker; Steven G. Docimo; Ilhami Surer; Craig A. Peters; Lars J. Cisek; David A. Diamond; A. Caldamone; Martin A. Koyle; W. Strand; R. Moore; R. Mevorach; J. Brady; Gerald Jordan; M. Erhard; I. Franco

Objective To combine and analyse the results from centres with a large experience of laparoscopy for the impalpable testis with small series, to determine the expected success rate for laparoscopic orchidopexy.


The Journal of Urology | 1998

Current findings in diagnostic laparoscopic evaluation of the nonpalpable testis

Lars J. Cisek; Craig A. Peters; Anthony Atala; Stuart B. Bauer; David A. Diamond; Alan B. Retik

AbstractPurpose: We delineate the current findings and contribution of diagnostic laparoscopic evaluation in the management of nonpalpable testis.Materials and Methods: We reviewed all cases in which laparoscopy was considered the management associated with a nonpalpable testis in a 4-year period. Since our previous series, we have performed a careful examination for the testis after induction of anesthesia but before committing to laparoscopy. We recorded testis position and quality, character of the vas deferens and spermatic vessels, type of management and contribution of laparoscopy. We also reviewed contemporary published series and collated the findings of studies performed elsewhere.Results: We identified 263 nonpalpable testes in 225 patients between September 1992 and 1996. In 40 patients 46 testes (18%) were found during physical examination under anesthesia. Of the remaining cases considered appropriate for laparoscopy 215 with complete records were further analyzed. Only 12.6% could be conside...


The Journal of Urology | 1999

PEDIATRIC RETROPERITONEOSCOPIC NEPHRECTOMY USING 2 MM. INSTRUMENTATION

Joseph G. Borer; Lars J. Cisek; Anthony Atala; David A. Diamond; Alan B. Retik; Craig A. Peters

PURPOSE We describe several modifications of the retroperitoneoscopic approach to nephrectomy for benign renal disease, including the use of 2 mm. instrumentation and prone patient positioning. MATERIALS AND METHODS A total of 14 children underwent retroperitoneoscopic nephrectomy in the prone position. An inflatable dissecting device was inserted into the retroperitoneum after a small muscle splitting incision was made at the lateral border of the sacrospinalis muscle approximately 1 cm. below the costovertebral angle. After inflation the dissecting device was replaced with a 5 mm. cannula and pneumoretroperitoneum was maintained with carbon dioxide insufflation. Two 2 mm. trocars were then placed under endoscopic guidance. Dissection was performed using 2 mm. instrumentation and the specimen was retrieved through the largest port site. RESULTS Nephrectomy was performed in 9 girls and 5 boys 3 months to 9.8 years old. The preoperative diagnosis included chronic pyelonephritis with minimal renal function, reflux with a nonfunctioning kidney, multicystic dysplastic kidney, an upper pole dysplastic moiety with an associated ureterocele and a dysplastic kidney with a vaginal ectopic ureter. Mean operative time for retroperitoneoscopic nephrectomy was 142 minutes with an estimated blood loss of less than 15 ml. Contralateral ureteral reimplantation was performed after retroperitoneoscopic dissection in 5 patients. Overall average hospital stay was 2 days and there were no complications. CONCLUSIONS Several modifications of the retroperitoneal approach, including the use of prone patient positioning and 2 mm. instrumentation for visualization and dissection, may improve the safety and efficacy of this technique in children.


The Journal of Urology | 2010

Factors Associated With Delayed Treatment of Acute Testicular Torsion—Do Demographics or Interhospital Transfer Matter?

Aaron P. Bayne; Ramiro Madden-Fuentes; Eric A. Jones; Lars J. Cisek; Edmond T. Gonzales; Kelly M. Reavis; David R. Roth; Michael H. Hsieh

PURPOSE Testicular torsion is a true urological emergency. We determined whether a delay in treatment due to hospital transfer or socioeconomic factors would impact the orchiectomy rate in children with this condition. MATERIALS AND METHODS We retrospectively evaluated the records of boys seen at a single institution emergency department who proceeded to surgery for a diagnosis of acute testicular torsion from 2003 to 2008. Charts were reviewed for transfer status, symptom duration, race, insurance presence or absence and distance from the hospital. Orchiectomy specimens were evaluated for histological confirmation of nonviability. RESULTS We reviewed 97 records. The orchiectomy rate in patients who were vs were not transferred to the emergency department was 47.8% vs 68.9%, respectively (p = 0.07). Symptom duration was greater in the orchiectomy group with a mean difference of 47.9 hours (p <0.01). The mean transfer delay was 1 hour 15 minutes longer in the orchiectomy group (p = 0.01). Boys who underwent orchiectomy were 2.2 years younger than those who avoided orchiectomy (p = 0.01). Multivariate analysis showed that symptom duration and distance from the hospital were the strongest predictors of orchiectomy. CONCLUSIONS Data suggest that torsion is a time dependent event and factors that delay time to treatment lead to poorer outcomes. These factors include distance from the hospital and the time delay associated with hospital transfer.


The Journal of Urology | 1999

Fetal partial urethral obstruction causes renal fibrosis and is associated with proteolytic imbalance.

Rita Gobet; Jeffrey Bleakley; Lars J. Cisek; Martin Kaefer; Marsha A. Moses; Cecilia A. Fernandez; Craig A. Peters

PURPOSE We determine whether fetal bladder outlet obstruction induces renal fibrosis, and is associated with an alteration in the regulation of connective tissue degradation and the presence of fibrogenic interstitial cells. MATERIALS AND METHODS Partial bladder outlet obstruction was surgically induced in 33 fetal sheep at 95 days of gestation. These animals and 24 normal age matched controls were sacrificed at 109, 116 and 135 (term) days of gestation, and the kidneys were rapidly retrieved, drained and weighed. Representative whole kidney samples were snap frozen for assessment of deoxyribonucleic acid, protein and collagen content. Morphometric analysis and alpha-smooth muscle actin immunohistochemistry were performed on histological specimens from formalin fixed kidneys. Tissue extract from fresh kidney specimens were analyzed for metalloproteinase and tissue inhibitor of metalloproteinase activity. Urine samples obtained at the time of sacrifice were analyzed for electrolyte, creatinine and N-acetyl glucosaminidase excretion. RESULTS All obstructed kidneys were hydronephrotic and larger than age matched controls. Obstructed kidneys at term showed interstitial fibrosis, as measured by increased extracellular matrix volume fraction (45% in male obstructed kidneys versus 2.5% in normal male kidneys, p = 0.0004), increased total collagen content (120 mg./kidney in male obstructed versus 20 mg. in normal male animals, p = 0.016) and collagen/deoxyribonucleic acid content per kidney (2.78 versus 0.53 mg./mg., p = 0.016). Metalloproteinase-1 activity was significantly lower in obstructed kidneys (210 versus 380 U./mg. protein in normal kidneys). Tissue inhibitor of metalloproteinase activity was undetectable in both groups. The presence of an increased population of myofibroblasts often associated with fibrotic processes was seen by alpha-smooth muscle actin staining which was localized to interstitial cells throughout the cortex in obstructed kidneys. CONCLUSIONS Fetal partial bladder outlet obstruction induces renal interstitial fibrosis as early as 2 weeks after obstruction. A possible mechanism for this process is a shift in proteolytic activity to reduce matrix degradation in obstructed kidneys. These changes might be mediated by the increased number of fibrogenic interstitial cells. The observations suggest several potential approaches to developing an understanding of congenital obstructive uropathy.


The Journal of Urology | 1998

EXPERIMENTAL VESICOURETERAL REFLUX IN THE FETUS DEPENDS ON BLADDER FUNCTION AND CAUSES RENAL FIBROSIS

Rita Gobet; Lars J. Cisek; Pierro Zotti; Craig A. Peters

PURPOSE Prenatal diagnosis allows the early detection of vesicoureteral reflux in an increasing number of newborns, some of whom are born with impaired kidney function. This situation challenges our current understanding of the pathophysiology, natural history and, therefore, treatment of reflux. We created a fetal sheep model of vesicoureteral reflux to study the mechanisms of fetal reflux nephropathy. MATERIALS AND METHODS Vesicoureteral reflux was induced in fetal sheep at 95 days of gestation (term 140 days) by open bladder incision of the intravesical ureteral tunnel. All animals underwent urachal ligation and in female subjects mild bladder outlet obstruction was created with a gold ring. RESULTS At term reflux was detected in 18 of 28 renal units by filling cystography. Refluxing kidneys were hydronephrotic and larger than normal. At term mean kidney weight was 21.1 gm. (range 12.2 to 35.0) in male subjects with reflux compared to 8.5 gm. (range 6.5 to 11.3) in normal male subjects (p <0.001) and 11.5 gm. (range 8.5 to 15.8) in male subjects with urachal ligation only (p = 0.035). In female subjects there was no change in renal weight. Renal histology revealed a thin, structurally normal cortex with small subcortical cysts and a hypoplastic medulla with mesenchymal tissue replacing normal ducts. Total mean renal collagen content was significantly increased to 51.7 mg. (range 35 to 81) in the refluxing kidneys of male animals, while it was 23.8 mg. (range 12.1 to 38.4) in normal male animals (p = 0.03). The fractional excretion of sodium was elevated in refluxing kidneys based on sodium-to-creatinine ratios in bladder urine. CONCLUSIONS In a novel model of fetal vesicoureteral reflux we showed that prenatal reflux nephropathy is characterized by altered renal growth regulation, structural maldevelopment without overt dysplasia, excess matrix deposition and impaired excretory function.


The Journal of Urology | 1999

EXPERIMENTAL FETAL VESICOURETERAL REFLUX INDUCES RENAL TUBULAR AND GLOMERULAR DAMAGE, AND IS ASSOCIATED WITH PERSISTENT BLADDER INSTABILITY

Rita Gobet; Lars J. Cisek; Barry Chang; Carol E. Barnewolt; Alan B. Retik; Craig A. Peters

PURPOSE We assessed renal function and urodynamic status in animals with experimental congenital vesicoureteral reflux. MATERIALS AND METHODS Vesicoureteral reflux was surgically induced in male sheep fetuses at 95 days of gestation. After birth the animals were maintained on antibiotic prophylaxis. At ages 1 week and 6 months reflux was assessed by fluoroscopic voiding cystography. Cystometrography was performed with the animals awake. Serum creatinine, inulin clearance and the excretion of urinary N-acetyl-beta-D-glucosaminidase were measured at ages 1 week, 1 month and 6 months by surveillance urine cultures. Urinary concentrating capacity was assessed by desmopressin testing at ages 1 and 6 months. RESULTS Nine animals (18 renal units) were born after the induction of reflux. There was no reflux in 2 renal units, while reflux was mild in 2, moderate in 5 and severe in 9. In the 6 animals available for followup at age 6 months only severe reflux persisted. Reflux resolution was associated with normalization of bladder urodynamics. Surveillance urine cultures were negative until age 6 months, when infection developed in 3 of the 6 lambs. In all animals serum creatinine was normal during followup. Glomerular filtration rate in the lambs with reflux was no different from normal at age 1 week but it was significantly less than normal independent of infection at age 6 months (2.7 versus 3.9 ml./kg. per minute, p = 0.002). As an indicator of renal tubular injury the ratio of N-acetyl-beta-D-glucosaminidase-to-creatinine remained significantly higher in animals with reflux than in normal animals from ages 1 week to 6 months (51.0 versus 10.2 IU/mg., p = 0.03). Maximal concentrating ability after desmopressin testing was already less than normal by age 1 month with a maximal increase of 98 versus 435 mOsm./l. in lambs with reflux versus normal lambs (p <0.0001). It was further impaired by age 6 months. Urodynamic evaluation of the animals with reflux revealed decreased bladder compliance at age 1 week with normal voiding pressure. In addition, in those with reflux there was a more pronounced immature voiding pattern with multiple phasic contractions due to sphincteric activity as well as a post-void bladder contraction. CONCLUSIONS Our model of fetal vesicoureteral reflux induces alterations in renal function that are consistent with clinical observations and marked by altered tubular function but a relatively mild decrease in glomerular filtration. Bladder dynamics are altered, consistent with observations in human neonates with high grade reflux and bladder instability. Whether this represents cause or effect remains unclear. Our model permits focused study of the interaction of these factors in neonatal reflux and may allow the application of more specific therapies, particularly those directed toward mechanisms of renal and bladder dysfunction.


The Journal of Urology | 2000

Characterization of ureteral dysfunction in an experimental model of congenital bladder outlet obstruction

William F. Santis; Maryrose P. Sullivan; Rita Gobet; Lars J. Cisek; Raymond J. McGOLDRICK; Subbarao V. Yalla; Craig A. Peters

PURPOSE Ureteral dysfunction is a significant sequela of congenital bladder outlet obstruction. However, the structural and functional alterations associated with ureteral dysfunction are not well defined. A model of fetal bladder obstruction in sheep was used to characterize the changes in ureteral smooth muscle, extracellular matrix (ECM) and functional properties in response to bladder outlet obstruction. MATERIALS AND METHODS Partial bladder outlet obstruction was created in fetal sheep at gestational age 95 days via placement of a metal ring around the proximal urethra as well as ligation of the urachus. Ureters were harvested at 109 and 135 days (full term = 140 days) to determine the relative composition of smooth muscle, ECM and urothelium by morphometric analysis and to measure DNA and protein concentrations. Ureteral tissue from 135 day gestation obstructed and control sheep was harvested and immediately placed in Krebs solution. Smooth muscle strips (2-3 mm. x 7-8 mm.) were suspended in organ baths. The frequency and amplitude of spontaneous ureteral contractions was as well as the response to electric field stimulation (EFS) were determined. RESULTS Bladder outlet obstruction caused a significant increase in ureteral weight, smooth muscle mass and total ECM at both 109 and 135 days gestation. Total ureteral DNA was greater in obstructed compared with sham ureters at 135 days gestation. Obstructed ureters demonstrated greater amplitude and frequency of spontaneous contractions as well as more pronounced response to EFS when compared to sham ureters. CONCLUSIONS The fetal ureter responds to bladder obstruction with smooth muscle hyperplasia and hypertrophy which is associated with increased spontaneous activity and augmented response to EFS. ECM content is markedly increased indicating a shift in the balance of connective tissue synthesis and degradation. Congenital post-obstructive ureteral dysfunction therefore appears to be the result of dysregulated smooth muscle cell growth and altered ECM homeostasis producing abnormal ureteral contractility.


The Journal of Urology | 2011

The Impact of Surgical Approach and Urinary Diversion on Patient Outcomes in Pediatric Pyeloplasty

Aaron P. Bayne; Katie A. Lee; Eric D. Nelson; Lars J. Cisek; Edmond T. Gonzales; David R. Roth

PURPOSE Recent comparisons of the impact of the surgical approach on pediatric pyeloplasty outcomes have generally incorporated a form of internal ureteral drainage. We hypothesized that the surgical approach does not affect outcomes in children who undergo unstented pyeloplasty and stenting offers no long-term benefit in those with pediatric pyeloplasty. MATERIALS AND METHODS After receiving institutional review board approval we examined the records of all children who underwent initial pyeloplasty from December 2001 to December 2009. We compared unstented and stented pyeloplasties, and each surgical approach in the unstented group. RESULTS During the study period 367 pyeloplasties were performed, including 231 unstented and 136 stented procedures. When comparing unstented to stented pyeloplasties, there was no difference in the complication or failure rate. Of unstented pyeloplasties 71, 67 and 93 were done using a transperitoneal laparoscopic approach, a flank approach and dorsal lumbotomy, respectively. There were 5 failures, of which 2 were laparoscopic, 2 used a flank approach and 1 used dorsal lumbotomy (p = 0.51). A total of 31 patients, including 10 treated with a laparoscopic approach, 3 with a flank approach and 18 with dorsal lumbotomy (p = 0.02), required second procedures, of which 24 were temporary drainage for a urine leak. Univariate analysis of factors associated with secondary procedures in the unstented pyeloplasty group showed that only surgical approach was significant (p = 0.05). CONCLUSIONS In pediatric pyeloplasty there is no significant difference in outcome between stented and unstented repairs. In unstented repairs complications may vary by surgical approach. Regardless of the approach unstented pyeloplasty is safe and effective in the pediatric population.


The Journal of Urology | 2010

Cross-Sectional Evaluation of Parental Decision Making Factors for Vesicoureteral Reflux Management in Children

Michael H. Hsieh; Ramiro Madden-Fuentes; Aaron P. Bayne; Erika Munch; Sandra J. Alexander; Edmond T. Gonzales; Lars J. Cisek; Eric A. Jones; David R. Roth

PURPOSE Parental decision making in children with vesicoureteral reflux has potentially become more complex with the evolution of ethnic diversity in the United States, the Internet, the publication of contradictory clinical data and the emergence of minimally invasive surgery. We performed a cross-sectional study of parental management for pediatric vesicoureteral reflux. MATERIALS AND METHODS We administered a 26-item questionnaire to parents of children with vesicoureteral reflux seen at Texas Childrens Hospital urology offices or undergoing antireflux surgery at that institution. Univariate and multivariate analysis was done on patient disease characteristics, demographics, predicted reflux duration, surgery success rate, antibiotic cessation, complication risk, financial considerations, urologist recommendations, Internet information, friend recommendations, and postoperative voiding cystourethrography, renal ultrasound and recovery. RESULTS Enrolled in the study were 15 boys and 49 girls with a mean age of 3.5 years and a mean reflux grade of 2.8. Of the cases 37 were bilateral. Parents chose endoscopic treatment in 38 children, open ureteroneocystostomy in 9, antibiotic prophylaxis in 14 and observation without antibiotics in 3. Univariate analysis suggested that Hispanic parents rated ultrasound and financial considerations as more important than white parents (p <0.05). Multivariate analysis revealed that differences seen on univariate analysis may have been due to an association between race and income. Finally, 93.6% of parents rated urologist opinion as very or extremely important. CONCLUSIONS Data indicate that the parents of our patients highly value the opinion of the pediatric urologist when choosing treatment for their children with vesicoureteral reflux. Despite social changes the physician-parental relationship remains critical. Differences in parental decision making may be linked to associations between race and income.

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Craig A. Peters

University of Texas Southwestern Medical Center

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David R. Roth

Baylor College of Medicine

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Rita Gobet

Boston Children's Hospital

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Eric A. Jones

Baylor College of Medicine

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Aaron P. Bayne

Baylor College of Medicine

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Alan B. Retik

Boston Children's Hospital

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David A. Diamond

Boston Children's Hospital

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Michael H. Hsieh

George Washington University

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Anthony Atala

Wake Forest Institute for Regenerative Medicine

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