High and intermediate imperforate anus: results after surgical correction with special respect to internal sphincter function

Relation between the internal anal sphincter and defecation disorders in patients with anorectal malformations

OBJECTIVES

To investigate associations between the rectoanal inhibitory reflex (RAIR), type of congenital anorectal malformations (ARMs), type of operation that patients with ARM had undergone, and objectively measured fecal incontinence and defecation problems.

METHODS

We retrospectively included 69 pediatric patients with ARM. All underwent anorectal function tests at the University Medical Center of Groningen during the last 10 years. We assessed anorectal physiology using the Rome IV criteria and anorectal function tests.

RESULTS

We found the reflex in 67% of patients and all types of ARMs. All patients who had not been operated on, and those who had undergone less extensive surgery possessed the reflex. In contrast, patients who underwent posterior sagittal anorectoplasty, 44% possessed it. We found no difference between mean rectal volumes in patients with and without the reflex (251  vs. 325 mL, respectively, p = 0.266). We found that over time, patients without the reflex seemed to develop significantly higher rectal volumes than patients who had it. We did not find a significant difference between the reflex and fecal incontinence; however, it seems that the absence of the reflex, resting anal sphincter pressure, and fecal incontinence are related.

CONCLUSION

The RAIR seems present in patients with ARM irrespective of their malformation type. Corrective surgery, however, may impair this reflex. Seemingly, its absence results in constipation with enlarged rectal volumes and fecal incontinence. Every effort should be made to preserve this reflex during surgery and to use extensive surgical procedures as sparingly as possible.

Post-Operative Anorectal Manometry in Children following Anorectal Malformation Repair: A Systematic Review

Despite surgical correction, children with anorectal malformations may experience long-term bowel dysfunction, including fecal incontinence and/or disorders of evacuation. Anorectal manometry is the most widely used test of anorectal function. Although considerable attention has been devoted to its application in the anorectal malformation cohort, there have been few attempts to consolidate the findings obtained. This systematic review aimed to (1) synthesize and evaluate the existing data regarding anorectal manometry results in children following anorectal malformation repair, and (2) evaluate the manometry protocols utilized, including equipment, assessment approach, and interpretation. We reviewed four databases (Embase, MEDLINE, the Cochrane Library, and PubMed) for relevant articles published between 1 January 1985 and 10 March 2022. Studies reporting post-operative anorectal manometry in children (<18 years) following anorectal malformation repair were evaluated for eligibility. Sixty-three studies were eligible for inclusion. Of the combined total cohort of 2155 patients, anorectal manometry results were reported for 1755 children following repair of anorectal malformations. Reduced resting pressure was consistently identified in children with anorectal malformations, particularly in those with more complex malformation types and/or fecal incontinence. Significant variability was identified in relation to manometry equipment, protocols, and interpretation. Few studies provided adequate cohort medical characteristics to facilitate interpretation of anorectal manometry findings within the context of the broader continence mechanism. This review highlights a widespread lack of standardization in the anorectal manometry procedure used to assess anorectal function in children following anorectal malformation repair. Consequently, interpretation and comparison of findings, both within and between institutions, is exceedingly challenging, if not impossible. Standardized manometry protocols, accompanied by a consistent approach to analysis, including definitions of normality and abnormality, are essential to enhance the comparability and clinical relevance of results.

Comparing the fecal continence scores of patients with anorectal malformation with anorectal manometric findings

BACKGROUND

Patients undergoing surgery for anorectal malformation (ARM) may have defecation-related problems throughout their lives, even if they are perfect treated surgically. Assessment methods are needed to standardize the clinical outcomes of patients with ARM. The aim of this study was to compare the scoring systems (SS) with the anorectal manometry (AM) findings.

METHODS

The data of patients operated on for ARM were examined. Holschneider's, Rintala's, Krickenbeck's and Peña's questionnaires were executed to the patients and AM was performed.

RESULTS

Our study was completed with 23 patients. There was a statistically significant relationship between the anal resting pressure and Holschneider's questionnaire (HQ). There was a statistically significant relationship between the area under the curve in the maximum voluntary squeeze pressure-time graph (AUC) and the HQ and Rintala's questionnaire (RQ). A statistically significant difference was found between HQ and RQ scores and high type and low type of ARMs.

CONCLUSION

In our study, based on AM data, it was found that the use of HQ and RQ from the four SS we compared could be more effective in patients' follow-up. It was concluded that Peña's questionnaire and Krickenbeck's questionnaire should be used to determine the bowel management program of the patients rather than patients' follow-up.

LEVELS OF EVIDENCE

Level II.

Epithelial and ganglionic distribution at the distal rectal end in anorectal malformations: could it play a role in anastomotic adaptation?

PURPOSE

In anorectal malformations (ARMs), the epithelium of the distal rectal end is not well described. We histomorphologically evaluated epithelial and ganglionic distribution in the distal rectal end of ARMs resected during anorectoplasty to assess similarities and differences with normal anal canal structure.

METHODS

In this single-center retrospective study, specimens from 60 ARM patients (27 males, 33 females) treated between 2008 and 2019 were evaluated.

RESULTS

Epithelium type and alignment sequence as well as ganglionic distribution were similar in the distal rectal end and in a normal anal canal. Stratified columnar epithelium (anal transitional zone, ATZ) was seen in 49/60 (81.7%) cases and in all ARM types, including the no-fistula type. Anal crypts were identified in the stratified columnar epithelium (ATZ) of 46/49 (93.9%) patients. Regarding distal rectal end-resecting anorectoplasty, in 90% of patients, resection was performed distal to the Herrmann line. Ganglion cell distribution was exclusively proximal to the Herrmann line.

CONCLUSION

Epithelial and ganglionic distribution was similar in the distal rectal end of ARMs and in a normal anal canal. The ATZ is the epithelial boundary between the rectum and skin in a normal anal canal. ATZ preservation could reproduce anal canal structure in ARM reconstruction.

Post-operative strictures in anorectal malformation: trends over 15 years

AIM

For decades, paediatric surgeons have employed the standard posterior sagittal anorectoplasty (PSARP) approach to deal with patients with anorectal malformations (ARM). In recent years, we noted an apparent increase in the incidence of anal stricture after surgical repair of ARM following the introduction of laparoscopic pull-through and techniques aiming to preserve the internal sphincter-the internal sphincter sparing approach (ISSA). We decided to analyse our data to find out if these new trends had added to the problem of post-operative strictures.

METHODS

All patients with ARM at our institution from January 2000 to December 2015 were identified. A retrospective case note review was carried out. Data collected included patient demographics, type of ARM, operative details, and post-operative outcomes.

RESULTS

114 patients were identified. Ten patients were excluded. Of the remaining 104 children, 48 (46%) were female. Median age was 8.3 (range 1.2-16.8) years. Types of ARM were as follows: perineal fistula (15 patients), anterior stenotic anus (12), imperforate anus without fistula (10), vestibular fistula (32), rectourethral (bulbar) fistula (11), rectourethral (prostatic) fistula (14), rectovesical fistula (7), and cloaca (3). Twenty-seven patients with a perineal fistula or anterior stenotic anus underwent perineal procedures that were variably described by the different operating surgeons. The majority (15 patients) had an anoplasty, 5 had anal transposition, 5 had limited PSARP, and 2 patients had ISSA. Two patients with a cloacal anomaly underwent open cloacal reconstruction. Of the remaining 75 patients, 45 had a PSARP approach, 6 had a laparoscopic-assisted pull-through, and 18 had ISSA. Four girls with vestibular fistula had anal transposition and two boys with imperforate anus without fistula had anoplasty. 15 (14%) children developed anal stricture. Stricture incidence differed according to operation type. PSARP was the most commonly performed procedure, with only 6% developing a stricture. In contrast, 30% of ISSA patients and 50% of children who had laparoscopic pull-through developed a stricture. Strictures also occurred in 11 and 12% of children having anal transposition and anoplasty, respectively.

CONCLUSION

The laparoscopic-assisted pull-through involves tunnelling the sphincter muscle complex. We found that often the tunnels were not wide enough, resulting in narrowing not just at the ano-cutaneous junction but also at the deeper level. 50% developed strictures. We have modified our technique by ensuring that the tunnels are generous enough to allow the rectum to be pulled through without any resistance. ISSA unfortunately resulted in 30% of our patients developing strictures. This approach, started in 2004, was, therefore, abandoned in 2013. The standard Pena's PSARP, with or without a laparotomy, has stood the test of time. Any modification of this approach must be carefully thought through and audited meticulously. Strictures can cause significant morbidity, which may need several revisions, and the resulting redo anoplasties run the risk of sphincter damage, ironically which the newer modifications of ISSA were trying to conserve.

Pelvic floor in females with anorectal malformations--findings on perineal ultrasonography and aspects of delivery mode

BACKGROUND

Advice on the mode of delivery to females born with anorectal malformation (ARM) is needed. The primary aim was to evaluate the anatomy of the pelvic floor muscles in females with ARM operated with posterior sagittal anorectal plasty (PSARP). The second aim was to correlate the extent of muscle defects to the bowel symptoms.

METHODS

This interventional study with perineal 4D/3D ultrasonography describes the smooth muscles in the intestinal wall (neo-IAS), external sphincter, levators and anal canal using a muscle score (0-6 worst). The bowel symptoms were prospectively registered with Krickenbeck criteria score (0-7 worst).

RESULTS

Forty females with different subtypes of ARM, median age 13 (4-21), were followed up regarding bowel symptoms. Seventeen were examined with ultrasonography. Bowel symptoms were similar for those examined with ultrasonography and those not, median score 5 and 3 (1-7) respectively, (p=0.223, Fisher's exact test). All the females had at least one muscular defect. There was no significant correlation between muscle defects and bowel symptoms (p=0.094, Spearman's correlation).

CONCLUSION

Females with ARM have considerable defects in the pelvic floor without any significant correlation to bowel symptoms. All women with ARM would benefit from individualized predelivery evaluations and caesarian section should be considered.

Abnormalities in "low" anorectal malformations (ARMs) and functional results resecting the distal 3 cm

PURPOSE

"Low" anorectal malformations (ARMs) are considered minor anomalies of the distal rectum and anal-canal development. Nonetheless, the prognosis of affected patients is far from excellent, as some degree of constipation is a frequent complaint in the long-term follow-up. Constipation in "low" ARM has been reported in 42%-70% of cases. Vestibular fistulas seem to have the highest rate of constipation (not less than 61.4%). The aim of this study was to evaluate all the histological wall abnormalities of ARM with recto-perineal and recto-vestibular fistulas in order to identify features that could explain the bowel dysfunctions. Moreover, the resection of distal perineal and vestibular fistulas (last 3 cm) allowed evaluating functional results in "low" ARM series with extensive fistula resection.

METHODS

One hundred four specimens were collected from 52 patients (32 recto-perineal and 20 recto-vestibular fistulas) during the posterior sagittal anorectoplasty (PSARP). The distal 3 cm of aberrant anorectal canals (fistulas) was systematically resected and divided longitudinally. One portion was fixed for immuno-histochemical stainings (PGP 9.5, S-100, NSE), H&E, and tricromic stainings. The frozen sections of the second portion were incubated for enzyme histochemical stainings (AChE, etc.). The follow-up of 42 of 52 ARM was postoperatively evaluated at 3-8 years of age, and the assessment of the outcome after PSARP repair was in line with Krickenbeck's 2005 meeting parameters.

RESULTS

Muscle coat was abnormal in all cases (100%), showing aspect and absence of organization into the circular and longitudinal layers. The connective tissue was found to be irregular and abnormally represented in 100% of cases. Abnormal vascularization was detected in 5 cases (9.6%). All vestibular (100%) and 71.8% of perineal fistulas showed different degrees of enteric nervous system (ENS) anomalies. In the series of 42 patients followed up at least after 3 years of age, 40 cases (95.2%) showed postoperative good continence without use of laxatives (according to Krickenbeck's 2005 criteria).

CONCLUSION

Every wall component of the distal rectum can be affected by different structural abnormalities in "low" ARMs. Pediatric surgeons should take into consideration the implications of these structural abnormalities during radical treatment. The resection of a significant portion of the distal fistula seems to permit better functional results.

Pre- and postoperative rectal manometric assessment of patients with anorectal malformations: should we preserve the fistula?

BACKGROUND

Surgical correction of congenital anorectal malformations could be complicated by fecal incontinence. Some authors believe that preservation of the fistula is associated with improved outcome. Rectal manometry is a well-established method to evaluate postoperative functional outcome in these patients and can demonstrate successful transplantation of the fistula.

OBJECTIVE

Herein, we report the results of our series of patients with anorectal malformations and an externally accessible fistula, who underwent pre- and postoperative rectal manometry studies.

DESIGN

This is a prospective cohort study.

SETTINGS

This study was conducted at a tertiary neonatal and pediatric surgical center.

PATIENTS

Patients with anorectal malformations, who underwent preoperative rectal manometry of the fistula and postoperative rectal manometry of the neoanus between January 2002 and December 2011 were included.

MAIN OUTCOME MEASURES

Pre- and postoperative rectal manometry results were compared by using paired t test or contingency tables (p values <0.05).

RESULTS

Twelve female patients with rectoperineal (n = 7, 58%) or rectovestibular (n = 5, 42%) fistula were treated by anterior sagittal anorectoplasty or minimal posterior sagittal anorectoplasty. Complete transposition of the fistula was achieved in all patients. Normal presence of rectoanal inhibitory reflex was demonstrated in all pre- and postoperative rectal manometry studies. There were no differences between pre- and postoperative rectal manometry in the length of the high-pressure zone (2.3 ± 0.6 cm vs 2.5 ± 0.8 cm (p = 0.5)) and resting pressure (59.4 ± 18.2 mm Hg vs 62.1 ± 19.2 mm Hg (p = 0.62)). At a median follow-up of 665 days (range, 290-1165 days), all patients have voluntary bowel movements, with no incontinence or soiling.

LIMITATIONS

This study is limited by its small sample size and by single-institution bias.

CONCLUSION

Preoperative rectal manometry of rectoperineal or rectovestibular fistula showed the presence of functional anal structures within the fistula in all patients. We speculate that fistula-preserving surgery in patients with anorectal malformations is associated with improved bowel function outcome.

A fistula flap technique for correction of type II atresia ani and rectovaginal fistula in 6 kittens

OBJECTIVE

To report a surgical technique and long-term outcomes of type II atresia ani (AA) and rectovaginal fistula (RvF) correction, using a fistula flap technique in kittens.

STUDY DESIGN

Clinical study.

ANIMALS

Domestic shorthaired female kittens (n = 6) with type II AA-RvF.

METHODS

Diagnosis of type II AA-RvF was made by clinical examination and vaginography. The anomaly was surgically corrected by a fistula flap technique for reconstruction of the anal canal and anus, and by vaginoplasty. Kittens were monitored for short and long-term complications.

RESULTS

All 6 kittens were fecal and urinary continent in the immediate postoperative period. Postoperative complications occurred in 2 kittens: partial dehiscence between the anal and vaginal opening and a stenosis at the level of the rectal mucocutaneous anastomosis. Dehiscence healed by second intention and stenosis was treated by anoplasty. No long-term complications (median follow-up, 12 months; range, 12-17 months) were observed.

CONCLUSIONS

Reconstruction of the anal canal and anus using the fistula as a local flap in combination with a vaginoplasty can be effective to treat feline type II AA and RvFs.

Embryonic development of the internal anal sphincter in rats with anorectal malformations

BACKGROUND/PURPOSE

The embryogenesis of the internal anal sphincter (IAS) in anorectal malformations (ARMs) remains unclear. This study aimed to investigate the development of the smooth muscle in the terminus of the digestive tract in normal and abnormal rats.

METHODS

Rat embryos with ARMs were generated by administration of ethylenethiourea to pregnant rats. The normal rat embryos and embryos with ARMs from E13.5 to E21 were serially sectioned in the sagittal plane and stained immunohistochemically using specific antibody to α-smooth muscle actin (SMA). Temporospatial study was carried out on circular muscle of the distal portion of the hindgut.

RESULTS

α-Smooth muscle actin immunolabeling cells could not be observed in the hindgut on E13.5, E14, and E14.5. On E15, there were α-SMA immunolabeling circular muscle cells in the hindgut; and the distal portion of the circular muscle was not thickened in the normal and ARMs rats. From E16 onward, the smooth muscle with slight dilated terminus, which was characterized by the features of IAS, could be noted in the primitive anorectum. In the normal group, the circular muscle in the distal portion of the hindgut thickened slightly and became the musculature with shutter-like bundles. In the ARMs group, the α-SMA immunolabeling myogenic precursors of the smooth muscle could be observed in the primitive anorectum as well. The musculature was similar to that in the normal group. On E15 and E16, there was no significant difference in the development of the circular muscle in the 2 groups. Moreover, the terminus of the circular muscle in the hindgut did not reach the orificium fistulae in ARMs rats. From E17 onward, in ARMs rats, the funnel-shaped distal hindgut communicated the genitourinary tract with a narrow fistula; the dilated musculature at this portion thinned gradually and formed an acute angled extremity in the ARMs group rather than formed blunt extremity in the normal group; the terminus circular muscle in the dorsal hindgut reached the orificium fistulae. During the following gestational days, the circular muscle of the hindgut in both normal and ARMs rats continued its own tendency.

CONCLUSION

The IAS primordium started to appear at the terminus of the hindgut on E15 in the 2 groups. The IAS in the ARMs group failed to develop as well as that in the normal group. The IAS dysplasia occurred in the late embryonic development (E17-E21).

Imperforate anus: long- and short-term outcome

Anorectal malformations are common anomalies observed in neonates. Survival of these babies is currently achieved in most cases and improvements in operative technique, patient care, and better follow-up have led to improved functional results. A new, simplified classification system (Krickenbeck classification) and method of functional assessment has led to an improved understanding of these anomalies and has allowed for a better comparison of outcomes. Following successful anatomical repair and appropriate programs of bowel care, socially acceptable continence can be achieved in a majority of patients, especially those with an intact sacrum.

Parental experiences: care of children with high and intermediate imperforate anus

In this study parental experiences of care of children with high and intermediate imperforate anus were evaluated. A group of 45 parents of children with high and intermediate imperforate anus and two control groups participated. Data collection with individual questionnaires concerning the child's hospital care, information to the parent and the child, and involvement in the care of the child were performed. Parents of children with imperforate anus reported being less satisfied with the care of their child, and they were less content with information about their child's treatment compared with the control groups. The parents had been extremely involved in the follow-up treatment. Constipation and fecal incontinence are common and involve suffering for the children and their parents. Parents have to be motivated and supportive and have a great deal of patience to be able to put up with caring for these children, and it seems as if health care professionals have underestimated their problems.

High and intermediate imperforate anus: psychosocial consequences among school-aged children

BACKGROUND/PURPOSE

Imperforate anus is an unusual malformation, which, even after surgical intervention, usually entails constipation and fecal incontinence. This study aimed to evaluate ongoing psychosocial effects of this birth defect in school-aged children.

METHODS

Twenty-five children born with high and intermediate imperforate anus participated in the study, along with their parents and classroom teachers. One group of healthy children and 1 group of children with juvenile chronic arthritis, along with their parents, served as controls. Children and parents individually answered a questionnaire devised for this study. Parents filled out the Child Behavior Checklist and the children's teacher filled out the Teacher's Report Form.

RESULTS

According to test results, children with imperforate anus were happy and optimistic. They liked school better and reported better relationships with schoolmates than the other children. The index group reported statistically significantly more frequent constipation. According to parental responses, the imperforate-anus children suffered from fecal incontinence and odor, as well as constipation (P < .001). Index-group parents reported on the Child Behavior Checklist that their children had more emotional and behavioral problems. On the Teacher's Report Form, teachers reported few problems for the same children.

CONCLUSIONS

Patients with imperforate anus did not experience psychosocial impairment despite significant functional problems.

Transanal endoscopic-assisted proctoplasty--a novel surgical approach for individual management of patients with imperforate anus without fistula

BACKGROUND/AIM

Imperforate anus without fistula consists of a spectrum of defects with variable distance between the rectal pouch and the perineum. We have developed a novel surgical approach for individual management of these patients based on precise knowledge of the level of the anomaly.

METHODS

All consecutive patients with imperforate anus without fistula between 2002 and 2004 had sigmoidostomy performed after having failed to pass meconium in the first 24 hours. The upper pouch was intraluminally visualized using retrograde endoscopy through the sigmoid mucous fistula. The distal termination of the rectum was clearly identified as by convergence of the anal columns. Bright translumination of the endoscope light from the rectum to the anal dimple within the external sphincter indicated a low malformation amenable to transanal proctoplasty. The rectum was incised from below under endoscopic visual control. Poor translumination indicated a higher defect, in which case, the operation was converted to standard posterior sagittal anorectoplasty.

RESULTS

Seven patients (6 boys) were identified. Four patients (3 boys) completed transanal endoscopic-assisted proctoplasty. In all cases, the convergence of anal columns indicating rectal termination was right above the anal pit at the site of the maximal external sphincter squeeze. In 3 patients, the operation was converted to posterior sagittal anorectoplasty after verification of a higher anomaly by endoscopy. There were no operative complications. The median follow-up was 3 months (range, 1-26 months). All patients have an appropriate size anus and regular bowel actions.

CONCLUSIONS

Transanal endoscopic-assisted proctoplasty allows safe and anatomical reconstruction of the anorectum, as well as contemporaneous closure of the sigmoidostomy in a significant proportion of patients with imperforate anus without fistula, avoiding the potential complications associated with the open posterior sagittal approach.

Preservation of the fistula for reconstruction of the anal canal and the anus in atresia ani and rectovestibular fistula in 2 dogs

OBJECTIVE

To report a technique for correction of atresia ani and rectovestibular fistula with fistula preservation, and outcome in 2 dogs.

STUDY DESIGN

Case report.

ANIMALS

Two intact female puppies.

METHODS

The fistula was approached by episiotomy. A vertical median perineal incision was made starting dorsal to the anal region and extended to surround the fistula. The rectum and vagina were separated, and the end of the fistula was sutured to the skin.

RESULTS

Early postoperative complications included constipation, fecal incontinence, and perineal soiling, but long-term outcome was good in both dogs.

CONCLUSION

With careful dissection, the fistula and internal anal sphincter can be preserved and used in the surgical reconstruction of the anal canal and anus.

CLINICAL RELEVANCE

Preservation of the fistula may provide an internal sphincter that contributes to a better functional result during correction of atresia ani. A surgical approach that combines episiotomy and perineal incision for separation of the vagina and rectum, and preserves the fistula may decrease the risk of dehiscence.

Crucial Role of Rectoanal Inhibitory Reflex in Emptying Function After Anoplasty in Infants with Anorectal Malformations

Constipation is a common problem after reconstructive surgery for anorectal malformations. The underlying pathophysiology of the constipation in these patients is unclear. The objective of this study was to compare manometric disturbance in infants with and without post-anoplasty constipation. Anorectal manometry studies were performed within 12 months of anoplasty, as a part of the follow-up protocol, in 24 infants aged less than 3 years who had anorectal malformations. The manometric profiles studied were mean resting anal pressure (ArP), mean resting rectal pressure (RrP), mean resting rectoanal pressure gradient (RRPG), peak squeeze pressure (PSP), and the presence of the rectoanal inhibitory reflex (RAIR). Eight of 24 infants (33%) experienced constipation during the examination period. There was no difference in pressure profiles between low and non-low anomalies. In the non-constipation group, RrP was 5.1 mmHg, ArP was 21.0 mmHg, RRPG was 16.0 mmHg, and PSP was 88.4 mmHg. In the constipation group, RrP was 7.3 mmHg (p = 0.37), ArP was 37.5 mmHg (p = 0.03), RRPG was 3.05 mmHg (p = 0.05), and PSP was 81.7 mmHg (p = 0.77). RAIR was present in 93.75% of cases without constipation and 12.5% of cases with constipation (p < 0.01). One patient who had clinical conversion from constipation to a good result also showed positive conversion of the RAIR. RAIR and anal resting tone play important roles in emptying function. As far as possible, these functions should be preserved during reconstruction.

Clinical evaluation of fecal continence after posterior sagittal anorectoplasty in anorectal abnormalities

Introduction Posterior sagittal anorectoplasty (PSAKP) was introduced in 1982, by Repa and de Vries, as a new surgical procedure for patients with anorectal malformations. It was supposed to provide better chance for normal fecal continence. Meterial and methods Between 1991 and 2000, 50 patients with anorectal abnormalities underwent PSARP. In 43 patients PSARP was primary operation and in 7 it was a secondary procedure. At the time of study patients were not younger than 3, and not older than 13 years. Patients and their parents were interviewed, and fecal continence was graded as follows: voluntary bowel contractions, soiling less than once a week, soiling more than once a week, daily soiling and constipation. Results Amongst patients who underwent primary surgical correction, 74% had voluntary bowel contractions. Babies with perineal fistula, rectal atresia and stenosis presented with best results in term of voluntary bowel contractions (100%), as with vestibular fistula, ten of eleven patients. Only 18% of patients (atresia without fistula, vestibular fistula and bulbourethral fistula) had soiling. Patients with perineal fistula and rectal atresia and stenosis 40% were totally continent (voluntary bowel movements without soiling). The most frequent sequel was constipation, which appeared in 48%, without coincidence with frequency of soiling. The problem of constipation was surprisingly more frequent in patients with expected better prognosis in fecal continence. Conclusion Although PSARP offers a good esthetic result, only two third of patients have voluntary bowel movements and in about half there exists a problem with constipation, with necessary further treatment.

Earlier appearance and higher incidence of the rectoanal relaxation reflex in patients with imperforate anus repaired with laparoscopically assisted anorectoplasty

BACKGROUND

This study aimed to evaluate clinically and manometrically the anorectal function of patients with imperforate anus after repair with laparoscopically assisted anorectoplasty (LAR), as compared with the function of patients after undergoing the conventional method, posterior sagittal anorectoplasty (PSARP).

METHODS

The defecation status and anorectal manometry of patients with high or intermediate type imperforate anus repaired with LAR ( n = 9) and age-matched patients repaired with PSARP ( n = 13) were assessed and compared during the first year of postoperative follow-up evaluation. The defecation status was classified by the frequency of bowel openings (<1, 1-4, and >5 times per day). Manometric assessment was performed by an open-tip hydraulic capillary infusion system. The presence of the rectoanal relaxation reflex was determined, and the resting sphincteric pressure and resting rectal pressure were measured.

RESULTS

Seven of nine LAR patients had an "acceptable" frequency of one to four bowel openings per day, in contrast to 7 of 13 PSARP patients. The difference in the presentation of daily stooling is not significant ( p > 0.05). A positive RAR was detected in 88.9% (8/9) of the LAR patients, and in only 30.8% (4/13) of the PSARP patients ( p < 0.01). The presence of a rectoanal relaxation reflex also significantly correlated with an acceptable frequency of bowel opening (1-4 times per day) in both LAR and PSARP patients ( p < 0.05). Moreover, a rectoanal relaxation reflex was detected significantly earlier in LAR than in PSARP patients (4.9 +/- 1.2 vs 10.1 +/- 2.5 months; postoperatively p < 0.0001). Both the LAR and PSARP patients had a similar resting sphincteric pressure (21.5 +/- 4.7 vs 25.4 +/- 6.2 cm H2O; p > 0.05). By contrast, the resting rectal pressure was significantly lower in LAR than in PSARP patients (7.7 +/- 1.5 vs 11.5 +/- 1.3 cmH(2)O; p < 0.05).

CONCLUSIONS

In the early postoperative stage, patients repaired with LAR had more favorable findings in anorectal manometry than patients repaired with PSARP. Long-term follow-up studies to confirm a superior defecation continence achieved with LAR are warranted.

Laparoscopic repair of high imperforate anus

Numerous laparoscopic operations have replaced the traditional open procedure in both adults and children. These new procedures have allowed access to body cavities without significantly traumatizing intervening tissue. The laparoscopically assisted anorectal pull-through (LAARP) for high anorectal malformations (ARM) uses fundamental concepts learned from decades of high ARM repair and incorporates modern technologic advancements in surgical instrumentation and techniques. This laparoscopic approach offers good visualization of an infant's deep pelvis with a reconstruction technique that minimizes trauma to important surrounding structures. The laparoscopic repair can be completed in one stage, 2 stages, or 3 stages. Currently, either the 2-stage or 3-stage operation is recommended. With the 3-stage approach, a temporary colostomy is created initially followed by LAARP in several weeks to months. The colostomy then is closed several months later.

Treatment of anorectal anomalies by anterior perineal anorectoplasty

PURPOSE

The aim of this study was as an introduction of a technical modification to the anterior perineal approach for the treatment of anorectal anomalies (AA) and analysis of its long-term results.

METHODS

Forty-three children with AA underwent a modified anterior perineal anorectoplasty (APA), which involved the following technical guidelines: construction of a rectoanal muscular conduit through the levator ani muscle and the external anal sphincter, which were sutured to each other; preservation of the rectal end of the fistula; and invagination of the perineal skin through the neoanus. Fecal continence was assessed on average 7 years postreconstruction by Kelly's score.

RESULTS

Of the 20 patients (19 boys) with high AA, results were good, fair and poor in, respectively, 50%, 30%, and 20% of them. Results were good and fair in, respectively, 79% and 21% of the 14 patients (all girls) with intermediate AA. All 9 patients (7 boys) with low AA had good results. The differences among groups were statistically significant (P = .016).

CONCLUSIONS

This modified APA allows for the surgeon to securely identify, preserve, and reconstruct all anatomic structures that are relevant for fecal continence. The long-term results of this initial series suggest that this modified APA is a valuable alternative for the treatment of AA.

The failed anoplasty: successful outcome after reoperative anoplasty and sigmoid resection

BACKGROUND/PURPOSE

Children with anorectal malformations often have less than optimal results after repair. The authors report on five patients (ages 3 to 17 years) born with imperforate anus and treated with anoplasty as a newborn. At presentation, all patients were completely incontinent of stool. None had ever experienced voluntary bowel movements, and all wore diapers continuously.

METHODS

Perineal examination with the nerve stimulator showed the muscle complex was largely intact with good contraction, but the neoanus was outside of the muscle complex. Contrast enema showed massive dilation of the rectosigmoid colon and fecal impaction. A tethered spinal cord was excluded by magnetic resonance imaging (MRI). We treated these patients with a combined reoperative anoplasty via the posterior sagittal approach and sigmoid resection.

RESULTS

Within 6 months after the procedure, all patients had achieved complete continence. They had from one to three voluntary bowel movements per day without soiling.

CONCLUSIONS

Children with severe constipation and fecal incontinence after anoplasty should undergo evaluation by a surgeon. If examination shows a reasonably intact muscle complex and correctable anatomic defects, an excellent result can be achieved with appropriate reoperation.

The role of radiology in children with anorectal anomalies; with particular emphasis on MRI

Anorectal anomalies have a reported incidence of between 1 per 1000 and 1 per 9630 live births. The international classification subdivides anorectal malformations into high, intermediate, low and miscellaneous deformities with emphasis on the sex of the child. The classification is based on where the rectum terminates in relation to the levator ani muscles above the levator is termed a high (supralevator) lesion, at the level of the levator intermediate, and below is a low or translevator anomaly. A modified classification has recently been proposed by Pena based on his anatomic observations during posterior sagittal anorectoplasty-the terms high, intermediate and low lesions continue to be used but with slightly different connotations. Approximately 50% of all patients with anorectal anomalies have associated other congenital lesions. These lesions necessitate a variety of radiological investigations which will be outlined briefly. The pertinent muscular anatomy of the pelvic floor and recent advances in surgical techniques will be discussed. The particular role of MRI in the evaluation of the pre-operative newborn or infant prior to definitive pull-through repair surgery and the post-operative, older, paediatric patient with continuing problems will be reviewed. Reference to the other radiological options, and their usefulness, in the evaluation of anorectal malformations will be made throughout the text.

Magnetic resonance imaging of anal sphincters after reconstruction of high or intermediate anorectal anomalies with posterior sagittal anorectoplasty and fistula-preserving technique

BACKGROUND/PURPOSE

Internal anal sphincter (IAS) function can be expected in approximately 75% of cases of high or intermediate anorectal anomaly reconstruction if the fistula region is preserved and transposed to become the new anal canal.

METHODS

To investigate the morphology of the IAS structure, magnetic resonance (MR) imaging was performed postoperatively in 14 patients operated on with posterior sagittal anorectoplasty (PSARP) and fistula-preserving technique. The results were compared with the appearance of the anal canal in seven normal children. In addition, comparison was made with the images of five patients operated on with earlier pull-through techniques, in which the fistula region was resected.

RESULTS

In all patients operated on with PSARP and fistula-preserving technique, the MRI displayed an IAS-like smooth muscle structure encircling a closed anal canal. In comparison with normal controls, the image of this IAS was more irregular and had greater variations in thickness in different directions. Moreover, the area of the IAS structure was larger in comparison with the controls. Eleven of the 14 patients showed a positive rectoanal inhibition reflex in rectoanal manometry. However, the MR findings of the three cases lacking the reflex were not different compared with the rest of the group. The five patients operated on with earlier techniques demonstrated an open anal canal without a measurable IAS smooth muscle component.

CONCLUSIONS

An IAS smooth muscle structure was seen by MRI in all patients operated on with PSARP and fistula-preserving technique independently of the severity of the malformation and the postoperative physiological IAS function. However, this structure was in most cases more voluminous and irregular compared with normal controls.

Anorectal anomalies: anorectal manometric function and anal endosonography in relation to functional outcome

To assess the relation between continence and the manometric and endosonographic state of the anorectal segment after surgery for anorectal anomalies (ARA), 33 adolescents operated upon for ARA and 14 controls were examined. Seventeen patients had low and 16 intermediate or high ARA. Fecal continence was recorded, and anal canal manometry was performed by microtransducer. The sphincter muscle complex and its relation to the anal opening was visualized by anal endosonography (ES). Ten patients had perfect continence, 10 had staining, and 13 had soiling. The anal canal resting and squeeze pressures were significantly different in all three groups, and continence function was significantly correlated to anal canal pressures. By anal ES, the internal (IAS) and the external anal sphincters (EAS) were identified with various amounts of scar tissue in all patients. In patients with high or intermediate anomalies the IAS was missing in the lower part of the anal canal, and abundant scar tissue was identified in the EAS in all patients. In patients with good continence function, the EAS was better preserved than in patients with major incontinence. The position of the anus in the EAS muscle complex was assessed, and varying degrees of eccentrically placed anal canals were identified. Continence function after surgery for ARA is thus correlated to anal canal pressures and ES images. ES, which is painless and suitable for use in children, is a valuable tool for assessing perianal structures, and the findings may serve as a helpful guide for corrective surgery.

The anterior sagittal approach for high imperforate anus: a simplification of the Mollard approach

High imperforate anus is a complex anomaly that requires a combination of careful preservation of native structures and precise anatomic reconstruction for optimal results. Previously the authors used an anterior perineal approach derived from the technique described by Mollard, with generally satisfactory results. The present report describes the authors' refinement of the technique to avoid skin perineal approach, via an anterior sagittal incision, usually is combined with a transverse suprapubic laparotomy. The technique includes division of the external sphincter and longitudinal muscle fibers anteriority, simple dilatation of the puborectalis, and division of the fistula close to the urethra, with preservation of the internal sphincter. The rectal pouch is brought down to the level of the puborectalis, without tapering, and the anoderm is brought up to the level of the rectal pouch to construct a shorter anal canal with a normal anorectal angle. This technique maximally preserves internal sphincter function, preserves specialized anoderm for the anal canal, and avoids extensive pelvic dissection and division of the levator sling. It also facilitates repair in the neonatal period, which may be optimal for long-term continence. The authors have used this technique in five patients, with good anatomic and short-term functional results. The authors believe that the technique provides optimal preservation of native tissues; only minimal destruction and dissection are required for reconstruction.

The rectoanal relaxation reflex and continence in repaired anorectal malformations with and without an internal sphincter-saving procedure

From 1985 to 1994, 27 patients with high- or intermediate type imperforate anus who underwent anorectoplasty were studied for postoperative function, particularly with respect to the rectoanal relaxation reflex and continence. Fourteen of the patients had a rectourogenital fistula and were treated with posterior sagittal anorectoplasty using the fistular end as the neoanus (internal sphincter-saving). Nine patients had a blind rectal pouch and received posterior sagittal anorectoplasty using the trimmed bowel end for reconstruction of the neoanus (incomplete internal sphincter-saving). The other four had Rehbein's mucosa-stripping endorectal pull-through combined with anterior sagittal anorectoplasty (none internal sphincter-saving). A positive rectoanal relaxation reflex was found in 8 of 14 (57.1%), 7 of 9 (77.8%), and 3 of 4 (75%), respectively. It appears that the internal sphincter-saving procedure is not essential for the development of the rectoanal relaxation reflex. Compensation or adaptation most likely contributes to the presence of the rectoanal relaxation reflex, and perhaps to postoperative continence.

Innervation patterns of the rectal pouch and fistula in anorectal malformations: a preliminary report

The innervation patterns of the rectal pouch and fistula of 52 children with anorectal malformations were investigated. Posterior sagittal anorectoplasty was used for intermediate and high anomalies; for the latter it was combined with an abdominal approach. Perineoproctoplasty was performed for low anomalies. The specimens were investigated by acetylcholinesterase staining, lactate dehydrogenase, and succinyldehydrogenase reaction. They consisted of fistula material only in 23 patients and of parts of the rectal pouch in 29. Fourty-four patients (84.6%) had follow-up, and information of bowel movements and continence was obtained after a mean of 3.3 years. Abnormal innervation patterns were found in 96% of the specimens. All fistulas were found to be aganglionic, including the adjacent part of the rectum involving the internal sphincter equivalent. Classical aganglionosis was found in 31% of the rectal pouch specimens, hypoganglionosis in 38%, neuronal intestinal dysplasia (NID) type B in 14%, and dysganglionosis in 10%. All patients with severe constipation or soiling at the time of follow-up had some histopathological correlation. Of the 25 patients for whom the specimens had consisted of rectal pouch material, nine (31%) had severe constipation. All four patients with a low-type malformation who had follow-up and pathological innervation patterns in the rectal pouch suffered from severe constipation; this was true of only five of the 19 children with intermediate or high malformations (P < .05). However, numerous pathological innervation patterns had been identified in patients who had normal bowel function at the time of follow-up. It is concluded that partial denervation of the rectum may not be the only cause in the pathogenesis of constipation after posterior sagittal anorectoplasty and perineoproctoplasty. The high frequency of neuronal intestinal malformations in the rectal pouch may be related to the higher frequency of bowel disturbances in patients with low malformations, in whom the resection was less radical. However, the clinical course is not necessarily related to specific histopathological findings. In the authors' opinion, the recommendation to use the distal rectal pouch and parts of the fistula in the reconstruction of anorectal malformations should be reconsidered.

How important is the role of the internal anal sphincter in fecal continence? An experimental study in dogs

It is a generalized concept that the internal anal sphincter (IAS) plays a significant role in fecal continence by generating high pressure in the anal canal at rest and relaxation during rectal distention. Agreement also exists on the importance of internal sphincter-saving anoplasty on anorectal malformations in establishing anal continence. Twelve dogs were divided into four groups. Group 1, a control group, was subjected to a perirectal dissection only. Group 2 underwent the same perirectal dissection plus a 2-cm resection of the anal canal. Group 3 underwent the perirectal dissection plus a 4-cm resection of the anal canal, and group 4 underwent perirectal dissection and transposition of the anus to the posterolateral portion of the voluntary muscle mass. Clinical continence was evaluated, and manometric results were compared with preoperative measurements. All dogs in groups 1, 2, and 3 were clinically continent without soiling except one in group 3, and also manometric results showed minimal change between preoperative and postoperative anal pressure profiles. The transposed anus of group 4 showed continuous fecal soiling. The anal resting pressure (ARP) was also decreased but still existed in this group. This experimental study showed that the IAS contributes to the anal resting tone. However, resection of the IAS did not completely interfere with fecal continence. The smooth muscle of pulled-through rectum seemed to partly take over the function of the IAS.

Constipation is a major functional complication after internal sphincter-saving posterior sagittal anorectoplasty for high and intermediate anorectal malformations

Anorectal function was clinically, manometrically, and radiologically followed-up in 40 patients who underwent an internal sphincter-saving posterior sagittal anorectoplasty in 1984 to 1989. The functioning internal sphincter was manometrically verified in 83% (33/40) of the patients. Soiling related to sphincter insufficiency was found in only 4 of the 33 patients with a functioning internal sphincter; 5 of the 7 patients without an internal sphincter had soiling. Symptomatic constipation was found in 73% (24/33) of the patients with a functioning internal sphincter, but in only 28% (2/7) of the patients without this structure. Constipation was not associated with a stenotic anal outlet in any patient. On anorectal manometry, there was no statistical difference in basal and pressures and internal sphincter reflex threshold values between constipated and nonconstipated patients. Histologically, ganglion cells were found in the proximal anal canal in all cases. The radiological size of the rectal pouch before closure of the protecting colostomy had a positive correlation with the severity of constipation. Medical treatment with diet and bulk-laxatives (13 patients) or with stimulant laxatives and occasional enemas (11 patients) successfully relieved constipation in 24 patients. In 2 patients, the symptoms were refractory to medical treatment and a resection of the megarectum was required. In conclusion, the preservation of the internal sphincter in patients with high or intermediate anorectal anomalies gives a good fecal continence outcome, but is associated with a high incidence of symptomatic constipation.