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Femtosecond time-resolved X-ray absorption (XANES) at the Co K-edge, X-ray emission (XES) in the Co Kβ and valence-to-core regions, and broadband UV-vis transient absorption are combined to probe the femtosecond to picosecond sequential atomic and electronic dynamics following photoexcitation of two vitamin B 12 compounds, hydroxocobalamin and aquocobalamin. Polarized XANES difference spectra allow identification of sequential structural evolution involving first the equatorial and then the axial ligands, with the latter showing rapid coherent bond elongation to the outer turning point of the excited state potential followed by recoil to a relaxed excited state structure. Time-resolved XES, especially in the valence-to-core region, along with polarized optical transient absorption suggests that the recoil results in the formation of a metal-centered excited state with a lifetime of 2-5 ps. This combination of methods provides a uniquely powerful tool to probe the electronic and structural dynamics of photoactive transition-metal complexes and will be applicable to a wide variety of systems.

Biallelic mutations in PMS2, a gene usually associated in heterozygous form with hereditary nonpolyposis colorectal cancer (HNPCC), results in a recently described childhood cancer syndrome. The tumor spectrum encompasses atypical brain cancers, hematologic malignancies, and colonic polyposis and cancer. Cutaneous stigmata resembling café-au-lait macules with more diffuse margins are frequently seen. Onset is as young as 2 years. The risk of second malignancy is high. Evidence exists for surveillance for bowel cancer, but surveillance for the wider tumor spectrum is of uncertain benefit. We report a consanguineous Australian-Lebanese family with multiple affected individuals shown to be homozygous for a PMS2 exon 7 deletion. We also review published cases of biallelic mutations in HNPCC-related genes. Early recognition of this familial cancer syndrome is critical, and should prompt investigation for familial HNPCC mutations.

Four patients who had imbrication of their proximal rectum and distal sigmoid colon as part of the management of constipation following an anorectoplasty for an anorectal anomaly. Three children with an anorectal anomaly presented with constipation and marked dilation of the rectosigmoid portion of the large bowel; each had longitudinal imbrication of the dilated segment, via a left iliac fossa incision. The forth was born with a cloacal anomaly with associated colonic atresia. The small bowel was used to construct the anorectum following a redo anorectoplasty. Subsequently, the small bowel became ectatic, resulting in the patient developing persistent watery diarrhoea and severe perianal excoriation, which was managed with a 30 cm longitudinal imbrication of the distal bowel during an extensive laparotomy. All 4 have patients now have near normal bowel motions with minimal medication, after only a short hospital stay. Residual problematic dilatation of the rectosigmoid colon in patients with a high anorectal anomaly, in the presence of constipation, can be successfully managed by imbrication of the dilated segment, if carefully selected.

Objective: To report our experience with autoaugmentation gastrocystoplasty (AAGC, reported to result in an inconsistent augmentation effect in children) in a sheep model, specifically addressing issues of surgical techniques and postoperative bladder drainage that may affect the augmentation result, as many factors have been implicated in the poor outcome., Materials and Methods: Ten 6-month-old male lambs had a suprapubic catheter placed by an open laparotomy. Intraoperative urodynamics were evaluated before and after detrusorotomy for autoaugmentation and after completing AAGC. The bladder was drained with no distension for 1 week after surgery and the urodynamic evaluation repeated on control and experimental animals 6 months after surgery. The animals were then killed and the bladders evaluated for gastric flap survival and histological changes in the native bladder and augmentation segments. The results were analysed using a one-sided Student's t-test., Results: The median (range) native bladder volume at leak-point pressure was 110 (40-490) mL. Intraoperative bladder volumes after completing AAGC confirmed adequate augmentation segments in all animals. The urodynamic evaluation at 6 months after AAGC showed increases in bladder volumes in nine of 10 animals (0-1336 mL), significantly greater than the increase in volume in the control sheep (median 337.5 vs 115.3 mL; P < 0.05). The bladder compliance (volume/pressure at leak capacity) 6 months after AAGC was slightly better but not significantly higher than in controls (median 17.3 vs 10.8 mL/cmH(2)O; P > 0.05). The median (range) ratio of surviving gastric flap to native bladder circumferences was 34.5 (31-53)%. Histology showed scarring of the submucosal layer in one of 10 augmentation segments and normal urothelium in all bladders., Conclusion: AAGC produces reliable bladder augmentation and excellent bladder compliance in a sheep model of a non-neurogenic bladder. The gastric flap survived well and there was no bladder wall separation with simple postoperative catheter drainage.

Purpose: Endoscopic ureterocele decompression is a well established procedure in children. However, an accurate endoscopic incision may be challenging in large ectopic ureteroceles. We describe a percutaneously assisted technique to facilitate the ease of ureterocele incision and review other described methods., Materials and Methods: We reviewed the medical records of 12 children with ectopic ureteroceles subtending a double collecting system who underwent endoscopic, percutaneously assisted incision. Six ureteroceles were on the left side, 5 were on the right side and 1 child had bilateral ureteroceles. Decompression results were evaluated by ultrasound and Tc-mercaptoacetyltriglycine imaging during a mean of 2.8 years of followup., Results: There were 7 girls and 5 boys. Mean age at presentation was 11.6 months (range 1 week to 6 years). The decompression success rate was 84% (11 of 13 renal units), and improved renal function and drainage was noted in 5 of 12 patients (41.6%). Seven of 12 patients had vesicoureteral reflux, of whom 2 were asymptomatic at followup and, hence, were treated conservatively. Five children underwent surgery because of recurrent urinary tract infections., Conclusions: Although our results are similar to those of other methods, percutaneously assisted cystoscopic incision of ureterocele enables easier and more accurate decompression. However, when comparing the various techniques described, it seems that postoperative results mostly reflect the anatomical and functional characteristics of the urinary system rather than the technique used.

Purpose: We developed a new procedure for the repair of proximal hypospadias in which the distal urethra is constructed as part of the first of 2 stages, and reviewed the results of 34 cases., Materials and Methods: We performed stage 1 of the Ulaanbaatar procedure in 35 children 0.6 to 11 years old (average age 2.5), and stage 2 in 20. The meatus was at the posterior third of the shaft in 14 children, at the penoscrotal junction in 16 and in the perineum in 5. Three patients had a previous operation, and none had Byars flaps formed. Followup was less than 2(1/2) years for stage 1 and less than 1(1/2) years for stage 2. In 2 stage 2 procedures a free graft was also used to augment the proximal part of the urethroplasty., Results: Urethral fistula did not develop in any patient, a minor early stricture occurred in 2 patients and 1 urethral diverticulum occurred in 1 patient after stage 2. In all patients the glans and meatus were more normal compared to other 2-stage procedures after the first operation, and the cosmetic result was usually satisfactory., Conclusions: The Ulaanbaatar technique provides an alternative approach to the formation of the glans urethra in severe hypospadias. It does not have the risks associated with a single stage procedure but has the benefit of enabling tunneling of the urethra through the glans, thus facilitating a favorable cosmetic outcome and an easy stage 2.

Purpose: The aim of this study was to report the results of 32 cases of dilatation of urethral stricture using a guide wire and sheath dilator technique supplemented by clean intermittent catheterization if further stabilization of the urethral stricture was felt warranted., Methods: The procedure involves insertion of a straight flexi-tip lubricated guide wire through the urethral stricture under cystoscopic guidance followed by insertion of a series of sheath dilators. Dilatation was followed by insertion of a Foley catheter, which was left in situ for 1 to 3 days. Patients underwent repeat cystoscopy to evaluate the urethra for recurrent stricture and those with a recalcitrant stricture were commenced on clean intermittent catheterization (CIC) to stabilize the narrowing., Results: Thirty-two patients were included. They have been followed up for up to 2(1/2) years after their last cystoscopy (mean, 16 months). Thirteen of 32 patients had more than 4 dilatations under anesthesia. Twelve patients had undergone CIC postoperatively. Complications included a urinary tract infection in 3 boys and bladder spasms in one. No false passage or sepsis occurred with this approach., Conclusions: Guide wire-assisted urethral dilatation helps avoid risks associated with blind dilatation techniques and appears to be a safe and simple alternative for management of urethral strictures in pediatric urology.

A retrospective study was performed of 250 patients with cholelithiasis treated at the Royal Children's Hospital, (RCH) Melbourne, over 25 years by open operation; 32 (12.8%) had proven choledocholithiasis on either preoperative imaging, operative cholangiography (OpCG), or postoperative investigation. A further 3 had underlying congenital biliary abnormalities and were excluded from further study. Thirty-one of the 32 were explored at open operation, 27 after OpCG and 4 on clinical grounds. One retained common-bile-duct (CBD) stone was undetected until the postoperative period (1/250, 0.25%). Seven ducts were not cleared, giving a duct exploration failure rate of 22.6% (7/31). All 8 retained CBD stones were identified in the early postoperative period and managed with a variety of techniques, including endoscopic retrograde cholangio-pancreatography (ERCP). The incidence of retained stones after open CBD exploration was high (22.6%), and can be attributed to difficulties in operative technique dealing with the smaller paediatric CBD. In addition, haemolytic disease seems to induce a propensity for choledocholithiasis. Given the small numbers presenting with cholelithiasis to RCH (10 per year), it is suggested that a selective approach to CBD exploration is appropriate in children. With the increasing use of laparoscopic cholecystectomy in children and the inherent technical difficulties of laparoscopic operative cholangiography, ERCP may offer an alternative solution in dealing with CBD stones rather than open or laparoscopic CBD exploration.

Purpose: The role of foreskin reconstruction as part of distal hypospadias repair remains uncertain. Thus, we wished to define better the indications with a view to improving the success of this cosmetic alternative. We reviewed the outcome in a group of patients who underwent foreskin reconstruction to highlight the criteria for likely success., Materials and Methods: The records of 51 boys who underwent foreskin reconstruction from 1996 to 2001 were reviewed from a total hypospadias repair group of 223. Boys who underwent foreskin reconstruction were 4 months to 9 years old (median age 9.3 months). Surgery included a meatal advancement and glanuloplasty procedure in 22 patients, Mathieu urethroplasty in 2, King-Duplay repair in 2 and a meatotomy in 1, while in 24 with a normal glans meatus foreskin plasty was the only surgery. Cases in which the foreskin was required for chordee release and those in which the gap between the ventral aspects of the foreskin was wide were excluded from foreskin reconstruction. Also, patients were selected by intraoperative assessment of the ability to approximate the foreskin in the midline at the level of the coronal groove. If this maneuver can be performed without placing the foreskin under tension, the foreskin is considered suitable for reconstruction. All patients received regional and general anesthesia plus intraoperative antibiotics. After suitable urethroplasty the technique of foreskin reconstruction was generally similar for all types of the condition., Results: The result was excellent in 36 patients (70.6%) with a normal-appearing foreskin that retracted easily. There was a good result in 8 patients (15.7%) with a satisfactory meatus at the tip of the glans and a retractable foreskin but minor foreskin deformity. Only 3 patients had a minor complication, including a fistula through the prepuce in 2 and wound infection in 1. No boy had a complication due to urethroplasty and there were no urethral fistulas., Conclusions: Our study shows that foreskin reconstruction is successful, particularly if the proximal, coronal groove portion of the prepuce can be easily approximated manually and the procedure can be combined with a range of distal repairs. We would recommend reconstruction of the prepuce if parents would prefer their son to be uncircumcised, providing that the foreskin is suitable for preservation.

Following a recent report of an ELISA test for the detection of antibodies to silicone, we attempted to use the same assay in four patients with known exposure to silicone. These patients all gave similar positive results as did a number of control sera with no known silicone exposure. We conclude that this assay does not measure serum levels of antibodies to silicone.

Background: The aim of this study was to assess the clinical and radiological outcome after surgical treatment for primary -megaureter., Methods: A retrospective analysis of 16 patients who had reimplantation of 17 primary megaureters between January 1997 and April 2001 was performed. Patients who had additional urinary tract pathology were not included in this study. The intent of the study was to focus on the complex range of data points that were used to reach the decision to operate., Results: Six of eight patients with febrile urinary tract infections prior to surgery have been without infections postoperatively. One patient who presented with daytime wetting has less wetting postoperatively, and one baby who presented with failure to thrive and postfeed vomiting, is feeding well postoperatively. On ultrasound investigation, the median diameter of the megaureter prior to operation was 11 mm (range 6-24 mm). One month after the operation, dilatation of the ureter could no longer be demonstrated in 10, was reduced in six, and increased in one of 17 ureters. Three months postoperatively, hydroureter was no longer detected in 14 and was reduced in three. In comparison, the hydronephrosis 1 month postoperatively was reduced in six, unchanged in seven and worse in four out of 17 kidneys, and 3 months after the operation, hydronephrosis was reduced in 13 and was unchanged in four compared with preoperative findings. Renograms at 3 months postoperatively showed free drainage in the 11 kidneys with impaired drainage preoperatively, and drainage continued to be normal in all six kidneys with normal drainage preoperatively. Median pre-operative renographic split function was 47% (range 39-54%), and was not significantly changed 3 months after the operation., Conclusions: When the decision to surgically intervene was made on a multifactorial basis, reimplantation of a primary mega-ureter resulted in improved clinical status, reduced dilation of the ureter and renal pelvis, and free drainage of the upper urinary tract.

The contamination of intravenously administered fluid with foreign material has always been of major concern, but the in-vivo impact of silicone embolisation from administration of fluid via a peristaltic finger pump (PFP) has not previously been assessed. To determine whether silicone particles enter the lungs and to review the histological response, 10 rabbits received an IV infusion of 0.9% saline at 10 ml/kg per hour over a 72-h period, via an IVAC 591 PFP. The lungs were analysed for silicone particles with scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDXA). These results were compared with a control group of non-infused animals. Silicone particles were found in 8 of 10 animals in the experimental group and in 2 of 9 control animals, indicating that silicone particles are dislodged during pump-assisted IV infusions. The difference between the control and infused animals was statistically significant using Fisher's exact test (P = 0.023). However, silicone plastic particles in control animals suggest that there is also environmental exposure to silicone in addition to those particles that come from a therapeutic source. The additional finding of elemental silicon (which is one of the constituents of silicone plastic) in both infused and control animals in which silicone plastic was not found indicates that not all elemental silicon in animals reflects the presence of silicone plastic. The clinical significance of each of these two findings is yet to be determined.

In patients with congenital posterior urethral obstruction, transurethral fulguration (TUF) is usually the treatment of choice if the patient is in a stable condition. However, few papers have described the proportion of patients who need further fulguration. We reviewed 83 boys with a congenital obstructive posterior urethral membrane (COPUM) to assess the role of re-do fulguration, as judged by prospective video recordings. Between December 1990 and March 2000, 83 boys (aged from newborn to 15 years) underwent cystourethroscopy for investigation of a urethral anomaly and were found to have a COPUM. TUF was performed endoscopically with a hook diathermy electrode. Two to 3 months later boys who had cauterisation had a further urethroscopy and diathermy as required. Of the 83 membranous lesions in the posterior urethra, 38 were considered severe, 20 moderate, and 21 minor. Four patients had inadequate data to be properly classified. Eighteen (47.4%) of the 38 patients who had a severe obstructive membrane equired further endoscopic intervention to obliterate residual membrane elements. As over 45% of patients who had a severe obstructing membrane needed further fulguration, it is important to follow patients carefully and to repeat the cystourethroscopy.

Objective: To review the profile and outcome of patients in whom it was elected not to insert a bladder catheter as part of the management of Cohen transtrigonal ureteric reimplantation surgery., Patients and Methods: Between April 2000 and April 2001, 37 patients underwent ureteric reimplantation by the senior author, using the Cohen transtrigonal technique. The use of the catheter-less protocol began after the blockage of a suprapubic catheter soon after surgery; the catheter was removed with no adverse event. Subsequently, 27 of those undergoing ureteric reimplantation were selected not to have a bladder catheter. Later in the study a greater proportion of patients had no catheter inserted, as confidence with the catheter-less technique increased. Caudal anaesthetic, oral analgesia and a single dose of intravesical bupivacaine were used for pain relief. The children were monitored closely after surgery and a urethral catheter inserted in the one patient who had not voided after 6 h., Results: The patients generally tolerated the lack of a bladder catheter well. Of the 27 patients who did not have a catheter inserted at surgery, one required catheterization (a girl with bilateral duplex systems and large ureteroceles). Two children stayed in hospital for 2 days after surgery, one was discharged on the day of surgery, and the remainder went home on oral analgesia on the first day after surgery. Since starting the catheter-less approach, 10 patients have had a suprapubic catheter because they had more complex surgery, were older or because the approach had not developed sufficiently at the time of surgery., Conclusions: Intravesical ureteric reimplantation is not only safe when omitting a bladder catheter but, if used selectively, there appears to be a significant decrease in the hospital stay and discomfort after surgery.

Twelve patients who had a revision posterior sagittal anorectoplasty (PSARP) were evaluated by questionnaire. They were 11 months to 15 years old (median 5 years) at the time of revision surgery. All were born with an intermediate to high anorectal anomaly (ARM) and had ongoing problems of rectal prolapse (3), stenosis (1), faecal incontinence (9), or severe constipation (4). All but 1 had a huge megarectum with a poor anorectal angle and stool impaction, causing overflow incontinence. After revision surgery, marked improvement occurred in 7 and at least some improvement was achieved in the remaining 5. Previous severe constipation resolved in 2 and improved in another 2 children. The number of soiling episodes significantly decreased in 8 patients: while before surgery 8 had been wearing nappies all the time, only 2 use them postoperatively. The anorectal prolapse has resolved in 3 and sensation improved in 5, and as a group, there has been a reduced need for laxatives and rectal washouts. The favourable outcome of our patients confirms that PSARP is an excellent technique for revision surgery, and tapering of a secondary megarectum plus the formation of an anorectal angle can produce clinical improvement, even in more severe forms of ARM.

Objectives: To analyze the relationship between hydronephrosis due to urinary tract obstruction and the presence of the sonographic eggshell sign, which is a recently described crescent of increased echogenicity at the caliceal/parenchymal interface and possibly an indicator of raised intrarenal pressure., Methods: All patients presenting between 1996 and 1999 for surgical management of pelviureteral junction obstruction or congenital posterior urethral obstruction had films reviewed for the presence of the eggshell sign., Results: Of 94 patients, 40 presented postnatally and 54 had hydronephrosis detected on the antenatal ultrasound scan. Of the postnatal group, 16 (40%) had urethral obstruction, of whom 4 (25%) displayed the eggshell sign; in the 24 with pelviureteral junction obstruction, the echogenic pericaliceal crescent was seen in 5 (20.8%). Of the 54 in the prenatal group, 8 (15.4%) were found to have urethral obstruction, 5 (62.5%) of whom demonstrated the eggshell sign. Of the 46 prenatally diagnosed patients with pelviureteral junction obstruction, 31 (70.5%) displayed the eggshell sign before birth; we were unable to satisfactorily review 2 patients' ultrasound scans., Conclusions: Antenatally diagnosed hydronephrosis due to significant urinary tract obstruction seems to be related to the appearance of the eggshell sign on ultrasonography, particularly in those patients with pelviureteral junction obstruction. Those patients without significant caliceal distension and those with renal dysplasia or severe hydronephrosis with low-pressure kidneys were less likely to display the eggshell sign. Although the association with other causes of hydronephrosis is unknown, we believe these figures support the need for further investigation of the eggshell sign as a marker of raised intrarenal pressure to possibly provide another data point in the sonographic evaluation of congenital hydronephrosis.

Objective: To review the ultrasonography of patients who had undergone pyeloplasty for pelvi-ureteric junction (PUJ) obstruction, and document the changes in calyceal distension and parenchymal thickness after pyeloplasty, to attempt to establish an additional prognostic indicator., Patients and Methods: Fifty-eight patients who underwent pyeloplasty for PUJ obstruction were assessed retrospectively. Pre- and postoperative ultrasonograms were analysed for both pyelocaliectasis, graded according to the Society for Fetal Urology criteria, and the ratio of the depth of calyces to the thickness of the parenchyma (C/P ratio). Patients underwent nuclear medicine renography before and 3 months after pyeloplasty. The results were analysed using the paired t-test, Kruskal-Wallis test, Spearman's correlation coefficient by rank test and the Mann-Whitney U-test., Results: There was no significant difference in hydronephrosis grade before and after surgery (P < 0.05) but there was a significant difference in the C/P ratios (P < 0.01). There was no correlation between C/P ratios and the results of diuresis renography., Conclusion: Hydronephrosis as measured by an estimate of pelvic volume is an insensitive marker of improvement after pyeloplasty. Reduced calyceal distension correlates well with other favourable prognostic indicators. Therefore, the C/P ratio may be an additional indicator of the appropriateness of surgical intervention, and should be the subject of further study.

Objective: To report our experience with autoaugmentation peritoneocystoplasty (AAPC) in a sheep model, and to compare the results with autoaugmentation gastrocystoplasty (AAGC) in a sheep model and in paediatric patients., Materials and Methods: Ten 6-month-old male lambs underwent bladder augmentation by detrusorotomy. A flap of parietal peritoneum, dissected from the anterior abdominal wall, was used to cover the bladder mucosa. The sheep were evaluated by urodynamics 6 months after surgery. Bladder compliance (bladder volume/intravesical pressure) was calculated for the bladder capacity at leakage. The urodynamic results were compared with age-matched control sheep and with 12 sheep that had undergone AAGC; the results were assessed using the Mann-Whitney U-test., Results: In two of the 10 sheep, bladder volumes after AAPC increased by > 100%, although for the group, the mean (range) bladder volume after augmentation, at 159 (42-261) mL, was not significantly different from that before surgery (mean 143 mL). Bladder volumes after AAPC were not significantly different from those in the control sheep (mean 205 mL) but were significantly less than in the AAGC group (mean 317 mL; P < 0.05). Bladder compliance at leak capacity in the AAPC group (mean 5.4 mL/cmH2O) was also not significantly different from the controls (mean 9.1 mL/cmH2O), but was lower than the in the AAGC animals (median 14.6 mL/cmH2O; P < 0.05)., Conclusions: AAPC in a sheep model does not result in a reliable increase in bladder volume or compliance. The volume and compliance are inferior to those found in bladders augmented by AAGC.

Objective: To assess the clinical and radiological spectrum in boys with endoscopically severe posterior urethral obstruction, as there is a broad clinical spectrum which does not always correlate with the cystoscopic findings., Patients and Methods: Between December 1990 and July 2000, 39 boys (newborn to 12 years old) underwent cystoscopy to investigate a urethral anomaly and were found to have a severe obstructing posterior urethral membrane. Their voiding cystograms, video-recorded cystoscopy and presenting signs were reviewed., Results: Of the 39 boys assessed, a voiding cystogram and presenting signs were available in 36. Of these 36 boys, three cystograms were initially reported as normal, eight showed posterior urethral dilatation as the only feature, and the remainder had more severe bladder and upper tract changes. Fourteen were diagnosed after identifying antenatal hydronephrosis, four presented with voiding dysfunction, one with haematuria and 17 were found after investigation of a urinary tract infection., Conclusions: This study shows that a congenital posterior urethral membrane that has only a small posterior defect endoscopically can have a wide clinical and radiological spectrum. The difference in outcome may be caused by variations in the response of the bladder to the obstruction, resulting in a different effect on the upper tracts.

Five infants with giant omphalocele had persistent collapse of the left lung and required prolonged respiratory support. Narrowing of the left main bronchus, reversible with positive end-expiratory pressure, was identified radiographically in 3 infants, and we postulate that this relates to distortion of the bronchus within the constraints of the elongated, narrow thoracic cavity characteristic of these patients. The lung collapse may be precipitated by manipulation (reduction or attempted reduction) of the omphalocele. J Pediatr Surg 36:846-850., (Copyright 2001 by W.B. Saunders Company.)

Background: The application of pyeloureteric anastomoses in the management of pelviureteric junction obstruction is described., Methods: Two patients, one requiring a ureterocystoplasty for bladder augmentation but with a coexistent contralateral pelviureteric junction (PUJ) obstruction and the other with gross hydronephrosis but an atretic ipsilateral ureter, underwent trans-pyeloureteric anastomosis to relieve the obstruction., Results: Both patients demonstrated satisfactory drainage of the upper tracts on postoperative imaging., Conclusions: Transureteropyeloplasty represents a novel and valid technique of urinary tract reconstruction in complex cases of PUJ obstruction.

Purpose: We assessed the variable morphological expression of posterior urethral membrane by reviewing video recorded cystoscopy., Materials and Methods: Between December 1990 and July 2000, 86 males newborn to 15 years old undergoing cystoscopy for urethral anomalies were identified with a posterior urethral membrane. Recorded cystoscopy was reviewed and membrane degree was graded as minimal, moderate or severe., Results: Of the 86 boys with a membranous lesion in the posterior urethra the condition was considered severe in 40, moderate in 21 and minimal in 21. Four patients on whom data were too inadequately recorded to be properly classified were excluded from study., Conclusions: This study demonstrates that congenital posterior urethral membrane represents a spectrum of lesions and may vary in the degree of obstruction.

Objective: To develop a surgical protocol to induce vesico-ureteric reflux (VUR) in utero by ablating the ureteric tunnel in a fetal pig model., Materials and Methods: Fetal surgery was conducted on nine sows, which were divided into three groups according to changes in the surgical protocol. Sows in groups 2 and 3 received different anaesthetics and antibiotics, and the operating theatre temperature was increased. In all cases, the intramural part of the ureter was unroofed in the fetuses, which were then returned to the uterus. Upon delivery, cystograms were taken in the male piglets, and the urinary tracts removed for anatomical and histological examination., Results: All three sows in group 1 delivered healthy piglets, but the fetuses that had undergone surgery were mummified. In group 2 the animals survived the fetal intervention, as shown by ultrasonography after surgery, but the four sows aborted spontaneously within a week. In group 3, both sows delivered normally developed piglets, three of which had undergone ablation of the ureteric tunnel. VUR was present only in those renal units in which the ureteric tunnel was ablated, and this was associated with hydronephrosis, dilatation of the ureters and thinning of the renal parenchyma on gross pathological examination., Conclusions: The fetal pig model of VUR not only appears to be feasible, but with similarities in renal anatomy and physiology also seems to be ideal for investigating fetal VUR.

An abdominal mass in the first year after birth most commonly originates from the kidney. Renal masses in this age group are often cystic and may be associated with other abnormalities. We describe an unusual benign unilateral cystic lesion and coexisting pelviureteral junction obstruction in a newborn male with an otherwise morphologically and functionally normal urinary tract. A near normal kidney resulted from subsequent resection of the cyst wall combined with pyeloplasty.

The posterior sagittal anorectoplasty (PSARP) procedure for the definitive repair of children with imperforate anus was described in 1982. Unfortunately, surgeons in Papua New Guinea (PNG) have until recently not had the opportunity of being trained in the technique. Through the Medical Officer, Nursing and Allied Health Sciences Training Project (MONAHP) and Pacific Islands Project (PIP) of the Royal Australasian College of Surgeons, 65 Papua New Guinean children with an anorectal anomaly have undergone a repair, in conjunction with training of the surgical staff and medical students. A new technique for the management of a prolapsed colostomy has been developed and a protocol for management of PSARP patients postoperatively has been formulated. Patients referred to the paediatric surgical visiting teams were diagnosed and treated according to the stage their management had reached. Patients with a low anomaly were treated by a cutback procedure, those with a colostomy and a high lesion were managed by a PSARP and those with failed previous surgery were managed with a redo anorectoplasty, often without a covering colostomy. Data were collected on the patients treated and, where possible, the patients were followed during subsequent visits. 65 patients with an anorectal anomaly were treated, of whom 6 were treated with a cutback and 43 had a primary repair of a major anomaly. 5 of these 43 involved an abdominoperineal procedure. 19 children had redo surgery, 3 of whom had a second operation by the senior author, due to failure of initial postoperative management; 1 of these was for a failure to carry out the postoperative dilatations and 2 were due to poorly controlled constipation in the early postoperative period. A protocol for the postoperative dilatations was developed using shaped candles. Major complications were uncommon, in particular infections were rare despite the relative lack of facilities. However, difficulties with outpatient follow-up resulted in problems that could have been avoided. A large number of anorectal anomalies have been successfully treated as part of the MONAHP and PIP projects with local surgeons learning the technique. A protocol for follow-up and a technique for the management of colostomy prolapse have been developed.

Until 1993 complex surgery for children in Papua New Guinea (PNG) was usually conducted by general surgeons, or by overseas paediatric surgeons during ad hoc visits. There had been little coordination of these occasional international visits and no involvement in the surgical teaching program in the University Department of Surgery. Over eight years from July 1993 to July 2000, three Australian surgeons spent 33 weeks teaching paediatric surgery and paediatric urology, using lectures, tutorials and operative demonstration sessions. This paper is a report of the teaching and service provided by one surgeon (PAD) over 27 weeks in PNG and describes the development and training of the surgeon who will be the country's first qualified paediatric surgeon (MM). Other support given has been assistance with the publication of scientific papers, reviews of Masters' theses, the development of a proposal for investigation of the prevalence of renal tract anomalies and the development of protocols for the surgical management of anorectal anomalies and Hirschsprung's disease. In addition to this teaching, 311 children have had surgery during the 11 visits that form the basis of this report. The visits have been supported and funded by AusAID and the Royal Australasian College of Surgeons through the Medical Officer, Nursing and Allied Health Professional (MONAHP) and Pacific Islands Project (PIP) programs. An indication of the impact on the care of children with surgical diseases is evident from the improved skills and the changed referral patterns over the eight years.

Prenatal diagnosis of pelvicalyceal dilatation has produced clinical material that we are continually reinterpreting with the help of improving ultrasound equipment. However, the ability to predict the outcome for any one patient with marked dilatation remains poor. We describe a new sign that may help identify those fetuses who have high intrarenal pressure and therefore justify more aggressive management, while obviating the need for intervention for those in whom it is not present. The egg-shell sign consists of a thin crescent of increased echogenicity over a distended calyx and, in this case, was documented to be associated with other features of raised intrarenal pressure.

Vesicoureteric reflux is now recognized to be a disease which is different in boys and girls and known to be associated with renal parenchymal abnormalities in the fetus. Understanding the anatomy and reviewing the development of the radiologic investigation of vesicoureteric reflux helps put in context conclusions reached from recent clinical and laboratory studies, on which new insights into vesicoureteric reflux have been based., (Copyright 1999 S. Karger AG, Basel.)

Background: This is the first reported study of histologically confirmed migration from intravenous access devices in children., Methods: The capsules from around intravenous access devices were examined by light microscopy to determine the extent of the foreign body response; energy dispersive x ray analysis was performed to document the elemental content of the foreign material., Results: A fibroconnective tissue capsule was found around all the samples. Elemental silicon was found in six of 13 tissue samples, and a foreign body giant cell reaction was seen in three of these., Conclusions: The pseudocapsule that surrounds an implanted vascular access device often has residual foreign material, including silicone.