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D T Mininberg

Publications and source records attributed to D T Mininberg.

At least 19 recordsLinked to original sources
PubMed1997

Laparoscopic surgery in children with ventriculoperitoneal shunts: effect of pneumoperitoneum on intracranial pressure--preliminary experience.

OBJECTIVES: We monitored changes in intracranial pressure (ICP) in 2 children with myelodysplasia undergoing laparoscopic bladder autoaugmentation. Both children had ventriculoperitoneal shunts (VPS) secondary to Arnold-Chiari malformations (type II). METHODS: ICP was monitored through a 23-gauge needle placed into the shunt reservoir and connected to a pressure transducer and drainage system. Intraoperative mean arterial pressure, end-tidal CO2 (ETCO2), ICP, abdominal pressure, and cerebral perfusion pressures were all monitored. RESULTS: Both children demonstrated rapid onset and sustained increases in ICP of greater than 12 mm Hg above baseline to a maximum pressure of 25 mm Hg. The average cerebrospinal fluid removed from each patient was 30 cc, thereby lowering ICP with no adverse neurologic sequela. The pCO2 remained constant throughout the procedures, as measured by ETCO2. CONCLUSIONS: We believe that intracranial hypertension (IH) results from a "Valsalva-like" phenomenon, which causes cerebral vascular engorgement. In addition, the pneumoperitoneum may increase the resistance to outflow through the distal peritoneal catheter, causing a partial or complete shunt obstruction. Untreated IH may result in adverse neurologic sequelae from brain herniation in these children with hindbrain anomalies and potentially altered brain compliance. We believe it is prudent to perform intraoperative ICP monitoring in this subgroup of patients undergoing laparoscopic surgery and that IH should be treated by ventricular drainage.

Child↗
PubMed1996

Laparoscopic orchiopexy: clinical experience and description of technique.

PURPOSE: We reviewed the experience, early followup and technique of laparoscopic treatment of the nonpalpable undescended testis at our institution. MATERIALS AND METHODS: Charts of patients who underwent laparoscopic treatment of an intra-abdominal testis from September 1992 to October 1994 were reviewed. RESULTS: A total of 13 laparoscopic orchiopexies was performed on 11 children with nonpalpable undescended testes. In 10 cases sufficient length was gained on the spermatic vessels using laparoscopic dissection to perform tension-free orchiopexy without the need for division of the spermatic vessels. CONCLUSIONS: When localization of an intra-abdominal testis is confirmed, orchiopexy can be performed safely with minimal morbidity using a laparoscopic approach. Length of hospital stay and postoperative morbidity may be improved in comparison to traditional techniques.

Child↗
PubMed1996

Laparoscopic laser assisted auto-augmentation of the pediatric neurogenic bladder: early experience with urodynamic followup.

PURPOSE: We report our initial experience with laparoscopic laser assisted bladder auto-augmentation for treatment of the symptomatic pediatric neurogenic bladder. MATERIALS AND METHODS: Laparoscopic auto-augmentation of the bladder was performed in 2 children with myelodysplasia and high pressure neurogenic bladders unresponsive to medical management. Detrusorotomy was done using the KTP-532 laser. Laser energy was directed to the tissue to evaluate long-term effects of the procedure. RESULTS: Laparoscopic bladder auto-augmentation can be performed easily and with less morbidity compared to open auto-augmentation. Although results at 6 weeks showed improvement, enterocystoplasty was ultimately performed in both cases due to symptomatic recurrence of incontinence associated with increasing peak detrusor pressure and decreasing compliance. CONCLUSIONS: While this technique has the potential to offer minimally invasive correction in patients with low capacity, high pressure bladders, further modifications will be required to achieve long-term success.

Child↗
PubMed1995

Laparoscopic laser-assisted bladder autoaugmentation.

OBJECTIVES: The purpose of this study is to examine the feasibility of performing a laparoscopic bladder autoaugmentation and to assess the urodynamic characteristics of an autoaugmented bladder. METHODS: Laparoscopic bladder autoaugmentation was performed in 9 female canines (20 to 30 kg). Following laparoscopic access to the peritoneal cavity, a midline bladder seromyotomy was performed using the potassium titanyl phosphate 532 nm laser. This produced a large bladder diverticulum. Changes in bladder volume and compliance were quantified over a 3-month period of follow-up. RESULTS: Urodynamic evaluation demonstrated an increase in bladder capacity 6 weeks postoperatively in 8 of 9 dogs, with an average volume increase of 45%. Bladder compliance improved in 7 of 9 dogs with an average increase in compliance of 67%. Three months postoperatively, bladder capacity remained increased in 5 of 9 dogs, with an average increase in volume of only 5.3%. An improvement in compliance was sustained in 5 of 9 animals with an average increase of 13.9%. Laparoscopic exploration revealed grossly normal bladders with adhesions of omentum to the seromyotomy site in all canines and the anterior abdominal wall in 2 of 9 canines. Histologically, the seromyotomy site was devoid of muscle with an intact urothelium and a proliferation of loose connective tissue. CONCLUSIONS: The technique of laparoscopic bladder autoaugmentation can be performed easily in the canine model. Although results at 6 weeks show significant improvement, the longer term, 3-month results were not statistically significant. This technique has the potential to offer a minimally invasive correction for patients with low-capacity, high-pressure bladders that have failed pharmacologic treatment.

Abdominal Muscles↗
PubMed1994

Cryptorchidism.

Explore the source record for details and available documents.

Adult↗
PubMed1993

Antisperm antibodies in cryptorchid boys.

To explore whether the development of antisperm antibodies might play a role in inhibiting the future fertility of cryptorchid boys, 32 boys who underwent orchiopexy and 21 boys who underwent other inguinal surgeries were examined for the presence of antibodies to donor sperm. This group was compared to 23 boys who underwent noninguinal surgery or who had unrelated medical conditions. Using the indirect immunobead assay, 28% of the boys in the study group were found to have antisperm antibodies. These were predominantly of the IgG isotype. In the comparison group, only 1 boy (4%) had antisperm antibodies (P < 0.05).

Adolescent↗
PubMed1993

Patch graft urethroplasty using dye enhanced laser tissue welding with a human protein solder: a preclinical canine model.

We investigated the use of the KTP-532 laser to perform a patch graft urethroplasty in 24 adult male dogs using the inner preputial skin as the donor site. In group 1 (12 dogs) repairs were completed with conventional microsuturing techniques, while in group 2 (12 dogs) they were completed using the KTP-532 laser. In the laser welding group the addition of a protein solder (40% human albumin) doped with fluorescein was used. Assessment parameters included a preoperative and postoperative retrograde urethrogram, measurement of intraluminal bursting pressure in the first 6 animals in each group, operative time and histology. Operative time was 42% faster and acute intraluminal bursting pressures were significantly higher in the laser-solder group. No fistulas occurred in the laser-solder group compared to a 50% fistula rate in the suture group. Significant radiographic abnormalities were seen in the urethras of the suture repair group.

Albumins↗
PubMed1991

Anti-Müllerian hormone in three intersex conditions.

Anti-Müllerian hormone (AMH), secreted by embryonic testicular Sertoli cells, inhibits the development of Müllerian ducts in the male. An enzyme-linked immunoassay (ELISA) for AMH was used to investigate three intersex infants. The AMH level was correlated with each patient's degree of Müllerian duct development. Complete inhibition of Müllerian structures correlated with the normal levels of AMH in the infant with testicular feminization. Detectable levels of AMH were found in the hermaphroditic infant; however, these low levels reflected Sertoli cell inadequacy of the ovotestis, which was documented by a right rudimentary Fallopian tube and a normal uterus. In the infant with persistent Müllerian duct syndrome, (PMDS), the normal Müllerian derivatives are compatible with 1) an AMH receptor defect; 2) a biologically and immunologically abnormal AMH molecule, or 3) a functional AMH deletion. The lack of detectable AMH in this infant excluded the AMH receptor abnormality and thus directed authors' search for the specific defect to the AMH gene. Thus, this ELISA for AMH is as valuable a tool to the molecular biologist studying a precise genetic error as it is to the physician making a precise clinical diagnosis.

Anti-Mullerian Hormone↗
PubMed1989

Posterior urethral valves. Role of temporary and permanent urinary diversion.

Between 1960 and 1983, 67 boys were treated for posterior urethral valves. Despite adequate valve ablation, azotemia eventually developed in 19, and they underwent permanent urinary diversion. Normal renal function was not achieved in any of these children. Diversion does not appear to have changed the natural course of their renal insufficiency, which is most likely secondary to damage incurred prior to their initial presentation. Prognostic factors useful to identify this select population are examined.

Blood Urea Nitrogen↗
PubMed1989

Laser welding of pedicled flap skin tubes.

The efficacy of the carbon dioxide laser used at high power levels for tissue destruction is well established. This laser at lower power levels has been used to incise and anastomose blood vessels, tendons, nerves, dura, bowel, fallopian tube, vasa deferentia, ureters and skin. Laser welding is faster, reduces surgical manipulation and introduces less foreign material into the wound than conventional suturing techniques. We tested the feasibility of laser welding of pedicled flap skin tubes to determine if there is a potential application in reconstruction, particularly for hypospadias repair.

Animals↗
PubMed1988

Extracorporeal shock-wave lithotripsy for children.

We report the cases of 17 children between the ages of 3 and 17 years who underwent 19 treatments using extracorporeal shock-wave lithotripsy. Stone size averaged 14.9 mm, with a range of 3 to 25 mm. The number of shock waves delivered averaged 1720, with a range of 600 to 2000. Treatment time averaged 36 minutes, with a range of 15 to 55 minutes. The average length of hospital stay was 2.2 days. In nine of the 19 treatments the kidneys were rendered free of stones. There were no complications.

Adolescent↗
PubMed1987

The epididymis and testicular descent.

The surgical findings in 197 consecutive cases of cryptorchidism demonstrate a 63% incidence of unfurled epididymides. This anomaly was more prevalent with bilateral cryptorchidism. The associated hernias, testicular and epididymal appendages were also more common in the unfurled epididymides cases, particularly in those that were bilateral.

Child↗
PubMed1985

Epispadias: contending with continence.

Forty-seven patients with epispadias not associated with bladder exstrophy were treated at our institution over the last half decade. There were 8 female and 39 male patients, 37 of whom had retrosymphyseal epispadias. Of the 20 male patients with subsymphyseal epispadias and incontinence 13 had a fair to excellent result. Of the 7 females with retrosymphyseal epispadias and incontinence, all but 1 came to urinary diversion. An analysis of our data suggests that premature operative intervention precludes obtaining maximal functional and cosmetic results. In addition, the discrepancy in our overall success rate utilizing a one-stage technique versus a staged procedure favored by others may support the latter.

Adolescent↗
PubMed1985

Exstrophy of bladder: evolution of management.

Eighty-nine patients with bladder exstrophy were seen at our institution over the last fifty years. There were 63 males and 26 females. Cloacal exstrophy constituted 9 per cent of our experience. Twenty-seven patients underwent primary urinary diversion with subsequent genital reconstruction early on in our series. Of the 57 children operated on since 1951, 50 were judged eligible for and underwent a planned multistaged reconstruction. We realized a 50 per cent success rate. The majority of failures were diverted into an ileal conduit for persistent incontinence.

Asia↗
PubMed1985

The development of a male pseudohermaphroditic rat using an inhibitor of the enzyme 5 alpha-reductase.

Incomplete masculinization of the external genitalia occurred in male Sprague-Dawley rats treated with a potent inhibitor of enzyme 5 alpha-reductase at the critical period of sexual differentiation in utero. The studies were performed using the 5 alpha-reductase inhibitor, 4-methyl-4-aza-5-pregnan-3-one-20[s] carboxylate, one of a series of aza steroids known to competitively inhibit the enzyme 5 alpha-reductase. The degree of inhibition of male external genital development was dependent upon the dose of the inhibitor, and at a dose of 36 mg/kg X day, there was complete feminization of the external genitalia of the male animal with a urogenital sinus and a pseudovagina. These studies provide conclusive evidence for the hypothesis that 5 alpha-reductase activity and dihydrotestosterone (17 beta-hydroxy-5 alpha-androstan-3-one) formation are essential for normal differentiation of male external genitalia. Epididymidis, vasa deferentia, and seminal vesicles were present at all doses of the inhibitor, suggesting testosterone dependency. However, confirmation of the testosterone dependency of Wolffian ductal differentiation awaits further studies, particularly comparison studies with the rabbit and dog, since Wolffian ductal differentiation in the rat, unlike the rabbit and dog, is not abolished with the antiandrogen, cyproterone acetate. The presence of prostatic buds, despite complete external genital feminization, was unexpected and suggests that these structures may have different thresholds of response for dihydrotestosterone. Prostatic differentiation may have a much lower threshold, requiring less dihydrotestosterone for differentiation.

5-alpha Reductase Inhibitors↗