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Biomedical subjects

J C Langer

Publications and source records attributed to J C Langer.

At least 37 records · Page 2Linked to original sources
PubMed2000

Pediatric surgery on the Internet: is the truth out there?

BACKGROUND: The enormous amount of unmonitored medical information on the Internet prompted this investigation into the quality of pediatric surgery information on the Internet. METHODS: The Internet was searched for information on diaphragmatic hernia (CDH), abdominal wall defects (AWD), pediatric inguinal hernia (IH), and pectus excavatum (PE). Websites were characterized, classified, and evaluated for completeness, accuracy and bias toward or against the medical profession. RESULTS: A total of 141 websites were evaluated (N(CDH) = 37, N(AWD) = 49, N(IH) = 26, N(PE) = 29). A total of 59.6% targeted medical professionals, and 46.8% targeted the lay population. A total of 58.2% described symptoms and diagnosis. Etiology, pathology, surgery, postoperative course, and prognosis each were addressed by under 40%. A total of 58.2% were accountable for the information presented. A total of 93.1% were incomplete, 75.7% contained accurate information, and 97.7% were positive or neutral toward medical treatment. Among diagnoses, CDH had the highest percentage of websites owned by academic institutions. PE had the highest percentage of websites owned by lay people. PE websites also were the least accurate. CONCLUSIONS: Internet information on pediatric surgery varies significantly in quality. Lay people own most websites targeted at the lay audience, and the information may not reflect the opinions of most pediatric surgeons. Increasing use of the Internet by parents seeking medical information warrants an organized approach to ensure complete and accurate information online.

Abdominal Muscles↗
PubMed1999

Gastrocutaneous fistula in children after removal of gastrostomy tube: incidence and predictive factors.

BACKGROUND/PURPOSE: Removal of a gastrostomy tube may result in a persistent gastrocutaneous fistula. The authors reviewed their experience to determine the incidence of this event in children, and the factors that contribute to its occurrence. METHODS: Over a 3-year period, 32 children had a gastrostomy tube placed that was subsequently removed. Of these, 18 sites closed spontaneously and 14 had a persistent gastrocutaneous fistula (44%). The groups were similar with respect to age, sex, and diagnosis. Mean time from insertion to removal of the tube was 6.5+/-2 months in the group with spontaneous closure, and 29.8+/-8 months in the gastrocutaneous fistula group (P<.05). RESULTS: One of 17 (6%) children who had tubes removed within 8 months of insertion had a fistula, compared with 13 of 15 (87%) of those who had one removed after 9 or more months (P<.001). Patients with tubes inserted percutaneously (PEG) were less likely to have a fistula than those using the Stamm technique (28% v. 55%, not significant), although PEGs also tended to be in place for a shorter time before removal (12.6 v. 21.1 months). Steroids did not increase the likelihood of a fistula (50% v. 42%, not significant). CONCLUSIONS: The incidence of persistent gastrocutaneous fistula is high after gastrostomytube removal in children. The most important factor predisposing to this problem appears to be the length of time the tube is in place before its removal. Almost all tubes removed within 8 months will close spontaneously.

Child, Preschool↗
PubMed1999

Intestinal obstruction after lung transplantation in children with cystic fibrosis.

BACKGROUND/PURPOSE: Distal intestinal obstruction syndrome (DIOS) occurs in 15% of patients with cystic fibrosis (CF). The authors reviewed their experience to determine the incidence, risk factors, and natural history of adhesive intestinal obstruction and DIOS after lung transplantation. METHODS: Eighty-three bilateral transplants were performed in 70 CF patients between January 1990 and September 1998. All were on pancreatic enzymes preoperatively, and none had preoperative bowel preparation. Fifty-six patients (80%) had prior gastrostomy (n = 54) or jejunostomy (n = 2). Eighteen patients (25.7%) had a previous laparotomy for meconium ileus (n = 8), fundoplication (n = 4), liver transplant (n = 1), jejunal atresia (n = 1), Janeway gastrostomy takedown (n = 1), pyloromyotomy (n = 1), free air (n = 1), or appendectomy (n = 1). RESULTS: After lung transplantation, 7 patients (10%) required laparotomy for bowel obstruction (6 during the same hospitalization, and 1 during a subsequent hospitalization). The causes of obstruction were adhesions only (n = 1), DIOS only (n = 2), and a combination of DIOS and adhesions (n = 4). Adhesiolysis was performed in the 5 patients with adhesions, and a small bowel resection was also performed in 1 patient. DIOS was treated by milking secretions distally without an enterotomy (n = 3) with an enterotomy and primary closure (n = 1) or with an end ileostomy and mucus fistula (n = 2). Five had recurrent DIOS early postoperatively. One resolved with intestinal lavage, 2 were treated successfully with hypaque disimpaction, and 2 underwent reoperation; 1 required an ileostomy. The most important risk factor for posttransplant obstruction was a previous major abdominal operation. Obstruction occurred in 7 of 18 (39%) who had undergone a prior laparotomy versus 0 of 52 who had not (P < .001, chi2). CONCLUSIONS: (1) The incidence of intestinal obstruction is high after lung transplantation in children with CF. (2) Previous laparotomy is a significant risk factor. (3) Recurrent obstruction after surgery for this condition is common. (4) Preventive measures such as pretransplant bowel preparation and early postoperative bowel lavage may be beneficial in these patients.

Adolescent↗
PubMed1999

Transanal one-stage Soave procedure for infants with Hirschsprung's disease.

PURPOSE: Many centers perform a one-stage pull-through procedure for Hirschsprung's disease (HD) diagnosed in infancy. The authors have developed a one-stage pullthrough procedure using a transanal approach that eliminates the need for intraabdominal dissection. METHODS: Nine children aged 3 weeks to 18 months with biopsy-proven HD underwent a transanal pull-through procedure over a 13-month period. A rectal mucosectomy was performed starting 0.5 cm proximal to the dentate line, and extending proximally to the level of the intraperitoneal rectum. In the first eight children, intraperitoneal position was confirmed with a laparoscope placed through a 3- to 5-mm port in the base of the umbilicus. The muscular sleeve was divided circumferentially to allow full-thickness mobilization of the rectosigmoid junction. Manual transanal traction permitted direct visualization and division of mesenteric vessels with transanal mobilization above the transition zone. Ganglion cells were confirmed by frozen section, and the bowel was transected. The rectal muscular cuff was divided longitudinally, and the anastomosis was completed. The laparoscope confirmed orientation and adequate hemostasis. In a ninth patient, the identical procedure was performed, but with the laparoscope used only for confirmation at the end of the procedure. RESULTS: Operative time, including frozen sections, averaged 194 minutes (range, 169 to 250 minutes), and the average length of bowel resected was 12 cm (range, 7.5 to 22 cm). Four of the nine patients were discharged on postoperative day (POD) 1, four on POD 2, and one patient with Down's syndrome was discharged on POD 6. Median follow-up was 6 months (range, 3 to 14 months). One death occurred 2.5 months postoperatively secondary to sudden infant death syndrome. Complications included postoperative apnea spells (n = 1), mild enterocolitis (n = 2), constipation (n = 1), anastomotic stricture(n = 1), and muscularcuff narrowing (n = 1); each responded to nonoperative management. Stool output has ranged from four to eight per day. CONCLUSION: A one-stage pull-through for HD can be performed successfully using a transanal approach without intraperitoneal dissection. This procedure is associated with excellent clinical results and permits early postoperative feeding, early hospital discharge, and no visible scars.

Anal Canal↗
PubMed1999

Repeat pull-through surgery for complicated Hirschsprung's disease: indications, techniques, and results.

BACKGROUND: Most children with Hirschsprung's disease (HD) do well after a pull-through procedure. In the occasional child in which the operation fails, a repeat procedure may be necessary. METHODS: Nine children with HD aged 20 months to 9 years underwent repeat pull-through over a 4-year period. Original pull-throughs (six Soave, two Swenson, one Duhamel) were performed elsewhere 12 to 95 months earlier (median, 36 months). Indications for revision were stricture unresponsive to dilatation (n = 3) and acquired aganglionosis (n = 6). One of the latter had associated segmental intestinal neuronal dysplasia. One child with a stricture after a Swenson procedure underwent a repeat Swenson. The other eight underwent reconstruction using a Duhamel technique. Five had a defunctioning stoma before or at the time of repeat surgery. RESULTS: Median follow-up was 15 months (range, 4 to 40 months). Complications included wound infection (n = 2), anastomotic bleeding (n = 2), stoma leak (n = 1) or stenosis (n = 1), "kinking" at the top of the Duhamel (n = 1), and persistent septum (n = 1). Three patients have had a good outcome with normal stool patterns. One has intermittent soiling, and one has what is believed to be stool-holding behavior. Four have persistent obstructive symptoms caused by sphincter hypertonicity, which are being successfully managed nonoperatively. CONCLUSIONS: Repeat pull-through surgery can be performed safely in appropriately selected patients. Duhamel reconstruction usually is preferred for technical reasons, and a stoma is not always necessary. Outcome is generally favorable, but anal sphincter hypertonicity may cause persistent symptoms in some patients.

Digestive System Surgical Procedures↗
PubMed1999

Experience with procedural sedation in a pediatric burn center.

BACKGROUND: Burn care requires daily debridement, dressing changes, and assessment regarding the need for skin grafting. These procedures are painful and may require an operating room environment. METHODS: The authors reviewed their experience with 912 consecutive procedural sedations (PS) in 220 pediatric burn patients over a 2-year period to identify what influence PS had on patient care. Median patient age was 32 months, and body surface area burn was 7.2%+/-6%. Pharmacological techniques included oral and intravenous medications and N2O. The authors included all sedations given in the burn treatment area and excluded all treatments given in the intensive care unit or emergency unit. RESULTS: PS allowed for early aggressive wound debridement, virtually eliminated the need for operating room debridement (used in only 22 patients), and eliminated patient discomfort and fear often associated with subsequent debridements. Burn wound-related complications occurred in 54 patients and included wound infection (n = 18), graft loss (n = 9), and pneumonia (n = 4). The incidence of PS complications was 7% with the most common problems including decreased arterial saturation (n = 41), emesis (n = 11), and agitation (n = 8). No patient required intubation or transfer to an intensive care unit bed. The average length of stay (LOS) for all patients was 8.7+/-6.2 days, and 6.2+/-3.8 days in the 200 patients not admitted to the intensive care unit. This compares favorably with the 9.5-day LOS of patients treated in 1990. CONCLUSIONS: PS in burn patients allows for early aggressive debridement, decreases the use of the operating room for debridement, and a decrease in length of stay when compared with our previous burn patients. PS has a modest risk of complications, enhances the family's cooperation and satisfaction with health care provided, and should be an integral part of burn care in children.

Adolescent↗
PubMed1999

Primary gastric plasmacytoma: a rare cause of hypertrophic gastritis in an adolescent.

BACKGROUND: This report describes a 16-year-old patient with gastric rugal hypertrophy caused by a primary gastric plasmacytoma. She had a 3-month history of nausea and burning abdominal pain. Radiographic studies showed giant rugal hypertrophy. Superficial endoscopic gastric biopsies showed mild inflammation with plasma cells of polyclonal origin in the mucosa. When symptoms persisted, she underwent laparoscopic full-thickness gastric biopsy. There was monoclonal plasma cell infiltration histologically diagnostic of plasmacytoma and inconsistent with Helicobacter pylori-associated mucosa-associated lymphoid tissue (MALT) lymphoma. There was no evidence for involvement of the bone marrow or regional lymph nodes. The tumor did not respond to radiotherapy, necessitating total gastrectomy. METHODS: Blood samples were analyzed for interleukin (IL)-6 by enzyme-linked immunosorbent assay. Gastric biopsy and gastrectomy specimens were subjected to immunophenotyping for kappa and lambda light chains, CD45, CD20, and LN1 and to polymerase chain reaction analysis for herpes virus HHV8. RESULTS: There was no elevation in circulating IL-6 levels, militating against a pathogenesis akin to that of Castleman's disease. There was no evidence for infection with the Kaposi's sarcoma-associated herpes virus HHV8, which has recently been found in patients with multiple myeloma. CONCLUSIONS: This diagnosis and the characteristics of the tumor are very unusual, if not unique, for a patient of this age. The diagnostic evaluation of this patient also demonstrates the importance of deep endoscopic or full-thickness biopsies in some children with hypertrophic gastritis.

Adolescent↗
PubMed1999

Transduction of renal cells in vitro and in vivo by adeno-associated virus gene therapy vectors.

There has been an increasing interest recently in the possibility of treating renal diseases using gene therapy. The ability to pursue gene therapy for renal diseases has been limited by the availability of an adequate system for gene delivery to the kidney. Adeno-associated virus (AAV) is a defective virus of the parvovirus family that has a number of properties attractive for renal gene delivery: recombinant AAV contains no viral genes; expression of genes delivered by these vectors does not activate cell-mediated immunity; the virus is able to transduce nondividing as well as dividing cells; and both wild-type and recombinant AAV integrate into the host chromosome resulting in long-term gene expression. Studies were performed to determine whether AAV can deliver reporter genes to kidney cells in vitro and in vivo. These studies show that AAV can deliver reporter genes with approximately equal efficiency to human mesangial, proximal tubule, thick ascending limb, collecting tubule, and renal cell carcinoma cells in primary culture. Immortalized mouse mesangial cells are transduced at a much greater efficiency. Transduction can be enhanced by pharmaceutical agents up to sevenfold in primary cells (transducing up to 20% of primary cells per well) and as much as 400-fold in immortalized mesangial cells. AAV delivered in vivo by intraparenchymal injection results in at least 3 mo of reporter gene expression in tubular epithelial, but not glomerular or vascular, cells at the injection site. These data indicate that AAV can deliver genes to renal cells both in vitro and in vivo resulting in prolonged gene expression, and thus AAV can be a useful tool for renal gene delivery.

Animals↗
PubMed1998

Constitutive expression of the cyclin-dependent kinase inhibitor p21 is transcriptionally regulated by the tumor suppressor protein p53.

The tumor suppressor protein p53 has been implicated in the response of cells to DNA damage. Studies to date have demonstrated a role for p53 in the transcriptional activation of target genes in the cellular response to DNA damage that results in either growth arrest or apoptosis. In contrast, here is demonstrated a role for p53 in regulating the basal level of expression of the cyclin-dependent kinase inhibitor p21 in the absence of treatment with DNA-damaging agents. Wild-type p53-expressing MCF10F cells had detectable levels of p21 mRNA and protein, whereas the p53-negative Saos-2 cells did not. Saos-2 cells were infected with recombinant retrovirus to establish a proliferating pool of cells with a comparable constitutive level of expression of wild-type p53 protein to that seen in untreated MCF10F cells. Restoration of wild-type but not mutant p53 expression recovered a basal level of expression of p21 in these cells. Constitutive expression of luciferase reporter constructs containing the p21 promoter was inhibited by co-transfection with the human MDM2 protein or a dominant-negative p53 protein and was dependent on the presence of p53 response elements in the reporter constructs. Furthermore, p53 in nuclear extracts of untreated cells was capable of binding to DNA in a sequence-specific manner. These results implicate a role for p53 in regulating constitutive levels of expression of p21 and demonstrate that the p53 protein is capable of sequence-specific DNA binding and transcriptional activation in untreated, proliferating cells.

Base Sequence↗
PubMed1998

Sensitivity and cost minimization analysis of radiology versus olive palpation for the diagnosis of hypertrophic pyloric stenosis.

BACKGROUND/PURPOSE: Two strategies are commonly used for the initial diagnosis of hypertrophic pyloric stenosis (HPS): (1) physical examination and (2) radiologic evaluation using upper gastrointestinal series (UGI) or sonography. The authors wished to determine the sensitivity and relative cost of each strategy. METHODS: The charts of 234 patients presenting over 3 years with a history suggestive of HPS were reviewed retrospectively. Cost, expressed as mean diagnostic charges (MDC) and mean total charges (MTC), was calculated according to two theoretical models. In model A, all patients first are examined by a surgeon. If an olive is palpable, they proceed to surgery. If not, they are sent to radiology. In model B, all patients have radiologic investigation first, and then surgical evaluation if the study result is positive. RESULTS: Of the 234 patients, 150 had HPS (64%). Olives were appreciated in 111 of these (palpation sensitivity of 74%). There was one false-positive olive (0.7%) and no false-negatives. Sonography and UGI were equally accurate (sensitivity of 100%, 0.5% false-positive). Equations were generated to estimate MDC and MTC for our patient population under each model. In model A, MDC = $507 - ($221 x palpation sensitivity) and MTC = $2,543 ($240 x palpation sensitivity). In model B, MDC = $449 and MTC = $2,454, and costs were independent of ability to feel an olive. When cost was plotted against palpation sensitivity, model A yielded a lower MDC than model B if palpation sensitivity was at least 26%, and a lower MTC if palpation sensitivity was at least 37%. Because our palpation sensitivity was 74%, approximately $100 per patient would be saved by sending all infants suspected of having HPS to a surgeon for examination as an initial step. CONCLUSIONS: Although highly sensitive, imaging is superfluous if an olive is palpable. Children suspected of having HPS should have a surgical consultation before a radiology study as long as the surgeon's palpation sensitivity for an olive is at least 37%. Improved palpation skills will result in maximum financial savings.

Costs and Cost Analysis↗
PubMed1998

Circumcision and pediatric disorders of the penis.

Circumcision is a commonly performed procedure, but medical indications remain controversial. Most disorders of the penis in childhood can be diagnosed and managed by the primary care pediatrician. However, some require early recognition and surgical intervention, and prompt referral to a pediatric surgeon or urologist will optimize outcome. This article discusses the recognition and initial management of these problems, particularly those most commonly seen or followed in the outpatient setting. In addition, the authors review the issues of circumcision.

Balanitis↗
PubMed1998

Timing of video-assisted thoracoscopic debridement for pediatric empyema.

BACKGROUND: Video-assisted thoracoscopic debridement (VATD) is a new method of managing pediatric empyema. The purpose of this retrospective study was to determine the relation between the timing of VATD and its success in avoiding the need for open decortication. STUDY DESIGN: Twenty-one children aged 3 to 16 years (mean, 8 years) with symptomatic, loculated, parapneumonic empyema were treated with VATD at two tertiary pediatric centers between 1994 and 1997. The preoperative duration of symptoms, hospitalization, and previous need for thoracostomy drainage were compared between patients having VATD only and those who subsequently required a thoracotomy and decortication. Statistical analysis used the Wald chi-square test or Fisher's exact test with p < 0.05 considered significant. RESULTS: Video-assisted thoracoscopic debridement was successful in 15 patients (group 1) and unsuccessful in six patients (group 2), who required a thoracotomy and decortication. Group 1 had a shorter mean duration of preoperative symptoms (13 versus 27 days; p=0.03), a shorter median duration of preoperative hospitalization (6 versus 18 days; p=0.04), and a lower incidence of previous thoracostomy drainage (4/15 versus 5/6; p=0.05). CONCLUSIONS: The technique of VATD is most likely to be successful when used within one week of diagnosis of a loculated parapneumonic empyema. A prospective trial comparing VATD with intrapleural fibrinolytic agents for the initial treatment of pediatric empyema is needed.

Adolescent↗
PubMed1998

Long-term outcome after neonatal meconium obstruction.

OBJECTIVE: It is unclear whether children with cystic fibrosis (CF) who present with neonatal meconium ileus have a different long-term outcome from those presenting later in childhood with pulmonary complications or failure to thrive. We examined a cohort of patients with meconium ileus, and compared their long-term outcome with children who had CF without meconium ileus and neonates who had meconium obstruction without CF (meconium plug syndrome). STUDY DESIGN: Comparative study using retrospective and follow-up interview data. PATIENTS: Group 1 consisted of 35 surviving CF patients who presented with meconium ileus between 1966 and 1992. Two control groups were also studied: 35 age- and sex-matched CF patients without meconium ileus (group 2), and 12 infants presenting with meconium plug syndrome during the same time period (group 3). OUTCOME MEASURES: Pulmonary, gastrointestinal, nutritional, and functional status were reviewed, and surgical complications were recorded. RESULTS: Mean follow-up was 12.6 +/- 6, 12.6 +/- 6, and 9. 3 +/- 4 years in groups 1, 2, and 3, respectively. Patients without CF (group 3) demonstrated better growth and functional status, and had a lower incidence of pulmonary and gastrointestinal problems. Although the presence of meconium ileus among CF patients was associated with an earlier diagnosis, there were no significant differences between groups 1 and 2 with respect to hepatobiliary, nutritional, functional, or respiratory status. Meconium ileus was associated with a higher risk of meconium ileus equivalent (20% vs 6%), although this difference was not statistically significant. Long-term surgical complications (adhesive small bowel obstruction and blind loop syndrome) were seen in 27% of children with meconium ileus; there were no long-term surgical complications in groups 2 or 3, because these infants did not have any neonatal surgical procedures. Children presenting with complicated meconium ileus had a higher rate of long-term surgical complications than those with uncomplicated meconium ileus (36% vs 17%), and those managed with resection or enterostomy had more complications than those treated by enterotomy and lavage (33% vs 0%). CONCLUSIONS: Long-term outcome is similar in CF patients who present with meconium ileus and those who do not, except for a slightly higher incidence of meconium ileus equivalent, and a significantly higher rate of surgical complications. The risk of surgical complications is highest in those presenting with complicated meconium ileus and those undergoing resection or enterostomy. Patients with meconium obstruction who do not have CF have an excellent long-term prognosis. This information will be useful in counseling the families of infants presenting with neonatal meconium obstruction.

Cystic Fibrosis↗
PubMed1998

Congenital diaphragmatic hernia.

CDH is a developmental abnormality resulting in a diaphragmatic defect which permits abdominal viscera to enter the chest. Most cases occur through the posterolateral foramen of Bochdalek. The mortality rate associated with CDH remains high due to the presence of associated anomalies, pulmonary hypoplasia, and pulmonary hypertension in those with adequate lung parenchyma to initially support life. A large number of approaches have been used to manage these infants, including delayed surgical repair, pharmacologic treatment of pulmonary hypertension, high frequency oscillation, ECMO, and surfactant therapy. New, and as yet unproven, innovations such as permissive hypercapnea, fetal surgery, and liquid ventilation may provide greater hope in the future for severely affected infants. Although most surviving children with CDH do well, a significant incidence of gastrointestinal and neurologic morbidity still exists.

Extracorporeal Membrane Oxygenation↗
PubMed1997

Enterocytic gene expression is altered in experimental gastroschisis.

Gastroschisis is a congenital anomaly in which exposure of the intestines to amniotic fluid throughout fetal life results in nutrient malabsorption. To begin to understand the molecular basis underlying epithelial changes in this condition, we investigated enterocytic gene expression during fetal development. Gastroschisis was surgically created at 24 days gestation (term = 31 days) in fetal rabbits; sham-operated and unoperated fetuses served as controls. Bowel was harvested at 28 and 31 days gestation. Cellular lactase expression was detected using immunohistochemistry, and apolipoprotein A-I and cellular retinol binding protein II (CRBPII) mRNA levels were quantitated using Northern blot analysis. Despite absence of gross histological changes in the mucosa, lactase protein expression and apolipoprotein A-I and CRBPII mRNA expression were decreased in intestine from gastroschisis compared to sham-operated animals. Expression of GAPDH (a housekeeping gene) increased over the same period, suggesting that the changes in enterocytic absorptive gene expression associated with gastroschisis were relatively specific. In conclusion, a decrease in expression of a variety of genes involved in nutrient absorption and trafficking within the enterocyte may contribute to the absorptive defects seen in this gastroschisis.

Abdominal Muscles↗
PubMed1997

Histology and function of the internal anal sphincter after injection of botulinum toxin.

BACKGROUND: Children with Hirschsprung's disease may have persistent obstructive symptoms due to internal anal sphincter hypertonicity, even after definitive surgery. Anal myectomy is not universally effective and may result in permanent sphincter injury. Botulinum toxin injection has been used to selectively weaken a variety of muscles and could theoretically represent a less invasive option for children with this difficult problem. We evaluated the efficacy and safety of botulinum toxin in an immature porcine model. MATERIALS AND METHODS: Six-week-old piglets underwent four-quadrant intrasphincteric injection of botulinum toxin or saline. Under ketamine sedation, internal sphincter resting pressure was measured using a water-perfused system before injection and 4 weeks later. Animals were sacrificed 4 weeks after injection. Histological evidence of neuromuscular changes or inflammation in the internal sphincter was documented. All analysis was done blindly. RESULTS: Internal anal sphincter pressure increased in control animals, likely due to growth over the 4-week period. Conversely, botulinum toxin injection was associated with a significant decrease in internal sphincter pressure. There were no significant differences between the botulinum toxin and control groups with respect to histologic evaluation of neuronal size and number, nerve bundle size and number, inflammation, or muscle atrophy. CONCLUSIONS: These data suggest that botulinum toxin is effective in decreasing internal anal sphincter pressure without histologically evident adverse effects. A clinical trial using botulinum toxin for persistent obstructive symptoms following surgery for Hirschsprung's disease is therefore justified.

Anal Canal↗