The transition zone in Hirschsprung's bowel contains abnormal hybrid ganglia with characteristics of extrinsic nerves.

The aganglionic bowel in short-segment Hirschsprung's disease is characterized both by the absence of enteric ganglia and the presence of extrinsic thickened nerve bundles (TNBs). The relationship between the TNBs and the loss of enteric ganglia is unknown. Previous studies have described decreasing numbers of ganglia with increasing density of TNBs within the transition zone (TZ) between ganglionic and aganglionic gut, and there is some evidence of spatial contact between them in this region. To determine the cellular interactions involved, we have analysed the expression of perineurial markers of TNBs and enteric ganglionic markers for both neural cells and their ensheathing telocytes across four cranio-caudal segments consisting of most proximal ganglionic to most distal aganglionic from pull-through resected colon. We show that in the TZ, enteric ganglia are abnormal, being surrounded by perineurium cells characteristic of TNBs. Furthermore, short processes of ganglionic neurons extend caudally towards the aganglionic region, where telocytes in the TNB are located between the perineurium and nerve fibres into which they project telopodes. Thus, enteric ganglia within the TZ have abnormal structural characteristics, the cellular relationships of which are shared by the TNBs. These findings will help towards elucidation of the cellular mechanisms involved in the aetiology of Hirschsprung's disease.

Role of Routine Dilatations after Anorectal Reconstruction-Comparison of Two Tertiary Centers.

AIM: Regular anal dilatations are commonly recommended in the postoperative management following posterior sagittal anorectoplasty (PSARP) in anorectal malformations (ARM). We hypothesized that routine postoperative dilatations may not affect surgical outcomes following PSARP. We compare surgical outcomes of routine postoperative dilatations versus no routine postoperative dilatations from two United Kingdom tertiary pediatric surgical centers. MATERIALS AND METHODS: This is retrospective records review of patients undergoing definitive surgery for ARM in two tertiary surgical centers in the UK over 5 years. Center A used a protocol of routine postoperative dilatations, and center B used a protocol, which used dilatations only for clinical indications of stricture. Data collected included ARM type, operative procedures, and postoperative interventions. All post-operative interventions under general anesthesia (GA) were compared between groups. RESULTS: From 2011 to 2015, 49 procedures (46 PSARPs) were performed in center A and 54 (52 PSARPs) in center B. Median follow up period was 31 months (interquartile range [IQR] 18-48). The first postoperative anal calibration under GA was documented for 43 (86%) patients in center A and for 42 (78%) patients in center B. Following this, center A followed routine postoperative dilatation (RPD) at home, and center B reserved further dilatations for specific indications. RPD was performed for 100% of patients in center A versus 8% in center B. Further anal dilatations under GA were performed in 19 (38%) children in center A and in 17 (34%) children in center B (p = 0.68). In center A, 10 patients (22%) needed further surgery versus 14 (28%) in center B (p = 0.48). CONCLUSION: The use of routine postoperative dilatations does not significantly improve surgical outcomes following PSARP in ARM.

Total esophagogastric dissociation: single center experience.

Aim: Fundoplication fails in approximately 20% of children with severe neurodisability. We aimed to evaluate total esophagogastric dissociation (TOGD) as a primary procedure and as a 'rescue' procedure for severely neurologically impaired children with significant swallowing discoordination and gastroesophageal reflux disease. Methods: Casenotes of 40 children with severe neurodisability who underwent TOGD between 2005 and 2015 were retrospectively reviewed. Of these, 33 were primary procedures and 7 were 'rescue' procedures following failed fundoplication. Results: Median age at surgery was 3 years 7 months (range 1 month to 13 years 11 months). Preoperatively, all children had symptoms of regurgitation, retching or vomiting and 70% of children had an unsafe swallow. There were 5 early complications related to surgery in 4 children requiring surgical intervention. One child died following relaparotomy for esophagojejunal anastomotic breakdown because of multiorgan failure. Gastrostomy feeding was established by a median of 6 days (range 2 to 25 days) and median hospital stay was 10 days (range 4 to 280 days). There were 5 late complications. Median follow-up was 13 months (range 1 month to 8 years 4 months). All children have had resolution of gastroesophageal reflux. Thirteen percent of children experience bloating or pain on feeding and 26% of children experience retching unrelated to gastroesophageal reflux. There were 8 late deaths unrelated to surgery. Conclusion: TOGD should be considered as a primary and definitive procedure in selected severely neurodisabled children who are at higher risk of failure of fundoplication, recurrent aspiration and a reduced quality of life.

Oblique anastomosis in Soave endoanal pullthrough for Hirschsprung's disease--a way of reducing strictures?

The Soave endorectal pullthrough is a commonly performed procedure for the definitive management of children with Hirschsprung's disease (HD). Anastomotic stricture is a recognised complication of this procedure. There are multiple causes for these strictures, circular anastomosis being one of them. There are techniques described which alter the shape of the anastomosis of the pulled through bowel to decrease the incidence of strictures. These are oblique and heart-shaped anastomoses. We describe a new technique of oblique anastomosis where the pulled through bowel is anastomosed posteriorly 0.5 cm from the dentate line, and anteriorly 1.5 cm above this point. This oblique anastomosis is designed to lower the stricture rate. If a stricture does occur, an anastomosis near the anocutaneous junction on the posterior aspect also faciltates Y-V anoplasty. We present our experience using this technique. Seventeen consecutive children underwent the procedure at our institution between 2003 and 2006. Only one child developed an anastomotic stricture requiring anal dilatation.