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Dive into the research topics where Mark F. Bellinger is active.

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Featured researches published by Mark F. Bellinger.


The Journal of Urology | 1993

Ureterocystoplasty : a unique method for vesical augmentation in children

Mark F. Bellinger

Vesical augmentation may be accomplished by using small bowel, large bowel or stomach, and by detrusor myotomy or the autoaugmentation technique. The use of intestinal segments is associated with variable mucus production, electrolyte absorption and the risk of malignant transformation. Autoaugmentation is free of these potential risks but may be unsuccessful in creating sufficient improvement in vesical compliance and capacity. Ureterocystoplasty with a bladder based native ureteral flap has been used in neurovesical dysfunction in association with a nonfunctional refluxing kidney, in a noncompliant valve bladder associated with posterior urethral valves and a nonfunctional kidney, and in augmentation of a small bladder after closure of cloacal exstrophy. Adequate bladder capacity and compliance have been achieved without the use of extra urinary epithelium. The surgical approach is simple and uncomplicated. Ureterocystoplasty in selected cases will provide for adequate bladder capacity and compliance when augmentation cystoplasty is required.


The Journal of Urology | 1993

The Limited Role of Imaging Techniques in Managing Children with Undescended Testes

Ronald L. Hrebinko; Mark F. Bellinger

We studied the usefulness of radiography for localization of cryptorchid testes. A total of 23 radiographic studies ordered by referring physicians was done for testis localization in 18 boys. Two patients had retractile testes and were followed expectantly. Ultrasonography failed to detect palpable testes in both cases. A total of 16 boys (19 undescended testes) underwent operative exploration and the findings were compared. Ultrasonography correlated with the operative findings in 7 of 12 cryptorchid testes (58%), while computerized tomography and magnetic resonance imaging correlated in only 4 of 12 (33%) and 0 of 1 (0%), respectively. The overall accuracy of radiological testing was 44%. Physical examination was 53% accurate when performed by the referring physician and 84% accurate when done by the attending pediatric urologist. In no case did radiographic assessment influence the decision to operate, the surgical approach or the viability/salvageability of the involved testes. Preoperative radiography for undescended testes is neither necessary nor helpful.


The Journal of Urology | 1999

AGE AT UNILATERAL ORCHIOPEXY: EFFECT ON HORMONE LEVELS AND SPERM COUNT IN ADULTHOOD

Michael T. Coughlin; Mark F. Bellinger; Peter A. Lee

PURPOSE We determined whether there are differences in hormone levels, such as inhibin B, follicle-stimulating hormone (FSH), luteinizing hormone and testosterone, and sperm density in men with a history of unilateral cryptorchidism as stratified by age at orchiopexy. MATERIALS AND METHODS A total of 84 men with a history of unilateral cryptorchidism presented to our institution for serum hormone measurement and semen analysis. These parameters were compared using Pearsons correlations and analysis of variance among 4 groups stratified according to age at orchiopexy (range 1 month to 11 years). RESULTS Comparison by Pearsons correlation analysis showed that age at orchiopexy significantly correlated inversely with inhibin B (r = -0.274, p = 0.012) and positively correlated with FSH (r = 0.229, p = 0.036). Comparison of mean hormone levels and sperm density by analysis of variance for linear trend revealed a significant relationship between age at surgery with inhibin B (p = 0.032) and testosterone (p = 0.029), while sperm density, FSH and luteinizing hormone were not significantly related. Post hoc comparison of individual means at surgery and at the time of this study demonstrated a significantly higher inhibin B level in the youngest age group than in 2 of the 3 older groups. CONCLUSIONS Men who previously had unilateral cryptorchidism and who underwent orchiopexy by age 2 years have higher inhibin B and lower FSH profiles than those who underwent surgery later in life. This finding suggests an overall beneficial effect of early orchiopexy in boys born with unilateral cryptorchidism.


The Journal of Urology | 1993

The multicystic dysplastic kidney and contralateral vesicoureteral reflux: protection of the solitary kidney.

Charles E. Flack; Mark F. Bellinger

The diagnosis of multicystic renal dysplasia is confirmed by a combination of sonography and radionuclide scan. If the contralateral kidney is normal by these criteria, further radiological examination is often omitted. We prospectively studied 29 patients with a diagnosis of multicystic renal dysplasia by voiding cystourethrography to determine the condition of the solitary contralateral kidney. Eight patients (28%) were found to have contralateral vesicoureteral reflux, of whom 6 had normal ultrasound examinations and would not have undergone further radiographic study based on ultrasound criteria alone. Contralateral vesicoureteral reflux in association with multicystic renal dysplasia puts solitary kidneys at risk for pyelonephritic scarring. Therefore, voiding cystourethrography should be performed as part of the initial evaluation of all infants with multicystic renal dysplasia.


The Journal of Urology | 1989

Orchiopexy: An Experimental Study of the Effect of Surgical Technique on Testicular Histology

Mark F. Bellinger; Howard Abromowitz; Stephen Brantley; Gary R. Marshall

Orchiopexy was performed in 35 mature Sprague-Dawley rats using absorbable suture, nonabsorbable suture or a classical dartos pouch technique without suture fixation. Examination of the chromic-fixed testes revealed severe acute inflammation of the suture site and most of the parenchyma in 76 per cent, with abscess formation in 65 per cent, complete absence of spermatogenesis in 82 per cent and evidence of tubular necrosis in 88 per cent. Nylon-fixed testes were adherent only at the sutures, with absent spermatogenesis in 29 per cent, moderate to severe tubular necrosis in 29 per cent and tubular atrophy in 58 per cent. Dartos-fixed testes demonstrated complete circumferential adherence, normal spermatogenesis in 94 per cent and minimal focal tubular atrophy in 23 per cent. Contralateral testes appeared normal in all animals.


Transplantation | 2003

Long-term results of pediatric renal transplantation into a dysfunctional lower urinary tract

Patrick Luke; Daniel B. Herz; Mark F. Bellinger; Pradip Chakrabarti; Carlos Vivas; Velma P. Scantlebury; Thomas R. Hakala; Anthony M. Jevnikar; Ashok Jain; Ron Shapiro; Mark L. Jordan

Background. The authors reviewed their long-term experience with pediatric renal transplantation into a dysfunctional lower urinary tract to evaluate the results of contemporary lower urinary tract evaluation and management on graft survival and function. Methods. Between 1990 and 1996, 21 renal transplants were performed in 20 children with dysfunctional lower urinary tracts and 61 transplants were performed in 61 patients with normal lower urinary tracts. The minimum follow-up was 36 months (mean, 62.0±19.6 months). The cause of lower urinary tract dysfunction included posterior urethral valves (n=13), prune belly syndrome (n=4), meningomyelocele (n=2), and urogenital sinus abnormality (n=1). Urodynamics were performed on all children with dysfunctional lower urinary tracts. Using these perioperative assessments, lower tract management strategies were devised, including timed voiding alone (n=6), clean intermittent catheterization (n=8), bladder augmentation (n=4), and supravesical urinary diversion (n=2). Results. Overall 5-year actuarial patient and graft survival rates were 100% versus 95% (P =not significant [NS]) and 83% versus 69% in the dysfunctional and normal urinary tract groups (P =NS), respectively. Mean serum creatinine levels in dysfunctional and normal urinary tract patients with functioning grafts at 3 years were 1.3±0.5 and 1.3±0.7 mg/dL, respectively (P =NS). However, 35% of patients with a dysfunctional lower urinary tract experienced urologic complications. Conclusions. Pediatric renal transplantation into a dysfunctional lower urinary tract yields outcomes comparable to transplantation into the normal lower urinary tract. Because of the high urologic complication rates, careful surveillance of lower urinary tract function by urodynamic evaluation is essential to optimize these outcomes.


The Journal of Urology | 2000

Paternity and hormone levels after unilateral cryptorchidism: association with pretreatment testicular location.

Peter A. Lee; Michael T. Coughlin; Mark F. Bellinger

PURPOSE We determined differences in paternity and levels of the hormones inhibin B, follicle- stimulating hormone, luteinizing hormone, testosterone and free testosterone based on the preoperative location of the undescended testis in men with previous unilateral cryptorchidism. MATERIALS AND METHODS Testicular location was determined by a review of the medical records and paternity or attempted paternity using a detailed questionnaire administered to 320 men with previous unilateral cryptorchidism. In 103 cases we performed semen analysis and measured the levels of the hormones inhibin B, luteinizing hormone, follicle-stimulating hormone, testosterone and free testosterone. Paternity, sperm count and hormonal parameters were compared with cryptorchid testicular location using analysis of variance and chi-square analysis. Logistic regression was done to analyze pretreatment testicular location as a risk factor for infertility. RESULTS Paternity, duration of attempted conception in men who achieved paternity, sperm count and hormone levels did not differ based on pretreatment abdominal, internal ring, inguinal canal, external ring, upper scrotum or ectopic testicular location. The overall paternity rate was 90% with the lowest rate of 83.3% in the abdominal group. More than 12 months were required to achieve conception in 28.9% of the study group overall and in 39.4% of the abdominal group. Varicocele and a partner with fertility problems were risk factors for infertility, while abdominal testicular location caused borderline significant risk. CONCLUSIONS Preoperative testicular location in men with previous unilateral cryptorchidism is not a major determinant of fertility according to paternity, sperm count or hormone levels.


The Journal of Urology | 1998

CORRELATIONS AMONG HORMONE LEVELS, SPERM PARAMETERS AND PATERNITY IN FORMERLY UNILATERALLY CRYPTORCHID MEN

Peter A. Lee; Mark F. Bellinger; Michael T. Coughlin

PURPOSE We compared characteristics related to fertility between formerly unilaterally cryptorchid men. MATERIALS AND METHODS We compared sperm counts and gonadotropin levels before and after gonadotropin-releasing hormone stimulation between formerly unilaterally cryptorchid men and controls who had completed a detailed questionnaire on fertility and other pertinent paternity information. These parameters were also compared between the subsets of formerly cryptorchid men who reported paternity and unsuccessful attempts at paternity. RESULTS Sperm density and total count, and basal and gonadotropin-releasing hormone stimulated follicle-stimulating hormone (FSH) levels were different in the cryptorchidism and control groups. Higher FSH levels and lower sperm counts correlated inversely in the cryptorchidism group, while luteinizing hormone, testosterone and other results of semen analysis did not differ. Furthermore, FSH levels were higher and sperm counts were lower in the subset who reported unsuccessful attempts at paternity compared with those reporting paternity. Other measured parameters did not differ between these groups. CONCLUSIONS FSH levels are significantly higher and sperm counts are significantly lower in formerly cryptorchid men than in controls. In the cryptorchidism group the same differences are found in fertile and infertile men. Thus, elevated FSH and low sperm counts may be considered risks for infertility in formerly cryptorchid men.


Journal of Pediatric Surgery | 1998

Testicular suture: A significant risk factor for intertility among formerly cryptorchid men

Michael T. Coughlin; Mark F. Bellinger; Ronald E. LaPorte; Peter A. Lee

BACKGROUND/PURPOSE Although fertility is decreased after cryptorchidism, the importance of risk factors, including parenchymal testicular suture, is unknown. The aim of this study was to examine the relationship between parenchymal testicular suture and failure to conceive a child for 1 year or longer among formerly cryptorchid men. METHODS Men who underwent orchidopexy between 1955 and 1972 at the Childrens Hospital of Pittsburgh (n = 619) were surveyed by questionnaire and their medical records reviewed. Only the men who attempted to conceive a child (n = 387) are included. RESULTS Logistic regression analysis determined significant risk factors for infertility. Testicular suture was strongly related to infertility (RR, 7.56; 95% CI, 1.66, 34.39) as were bilateral cryptorchidism (RR, 5.51; 95% CI, 1.58, 19.24), varicocele (RR, 4.72; 95% CI, 1.42, 15.75), hormone treatment before surgery (RR, 3.69; 95% CI, 1.22, 11.11), and partner conception problem (RR, 3.32; 95% CI, 1.11, 9.90). CONCLUSIONS Testicular suture was a potent independent determinant of infertility among formerly cryptorchid men who have orchidopexy. Bilateral cryptorchidism, hormone treatment, varicocele, and partner conception problems also were associated with increased infertility.


Fertility and Sterility | 1999

Absence of microdeletions in the Y chromosome in patients with a history of cryptorchidism and azoospermia or oligospermia

Julian Fagerli; Francis X. Schneck; Peter A. Lee; Mark F. Bellinger; Selma F. Witchel

OBJECTIVE To determine if cryptorchidism is associated with microdeletions of interval 6 of the Y chromosome, we evaluated this locus in men with a history of cryptorchidism with and without azoospermia or oligospermia and in a control group. DESIGN Clinical study. SETTING Academic research environment. PATIENT(S) Men in whom surgical treatment of cryptorchidism had been performed in childhood and healthy control male subjects. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Genotyping of interval 6 of the Y chromosome. RESULT(S) Analysis of semen obtained from men treated for cryptorchidism in childhood showed azoospermia or oligospermia in 14 of 38 (37%) men. No microdeletions were identified with polymerase chain reaction amplification of 17 distinct sequence tagged sites located on the long arm of the Y chromosome and the sex determining region on Y (SRY) gene. CONCLUSION(S) Microdeletions of interval 6 of the Y chromosome were not detected in either the formerly cryptorchid or in the healthy subjects. Although we cannot exclude the possibility of point mutations, we conclude that cryptorchidism or cryptorchidism associated with azoospermia or oligospermia is not due to microdeletions involving interval 6 of the Y chromosome.

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Peter A. Lee

Pennsylvania State University

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John W. Duckett

Children's Hospital of Philadelphia

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Ron Shapiro

University of Pittsburgh

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Carlos Vivas

University of Pittsburgh

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Daniel B. Herz

University of Pittsburgh

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