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Background: Atresia ani – the lack of an anal opening – is a rare condition in small animals. In some cases a connection forms between the blind end of the rectum and the skin (rectocutaneous fistula) that allows passage of feces. Only three cases have been found in the exotic mammal literature: two guinea pigs and one rabbit. Case presentation: A 6-month-old female guinea pig was presented for vocalization and difficulties during defecation that started 2 weeks before. During physical examination an imperforate anus and an abnormal opening located ventrally to it were detected. The guinea pig was able to pass very small feces through the abnormal opening with apparent discomfort. Once the stools were produced, the patient would go back to its normal behavior. A type 2 atresia ani combined with a rectocutaneous fistula was diagnosed. Surgical reconstruction of the anal canal preserving the fistula by means of using a pull-through technique to create a nonpainful, ectopic anus was performed. Conclusions and clinical relevance: Surgical treatment of rectocutaneous fistula was effective in the guinea pig of this case report. Future studies including a larger affected population and with long-term follow-up are needed.

Background: Constipation is a common problem after surgery for anorectal malformations (ARMs), especially in patients having preserved rectosigmoid after pull-down surgery. Here, we present our experience with patients having constipation after surgery for ARMs and briefly discuss its management. Materials and Methods: We retrospectively reviewed electronic operative and follow-up data from January 2015 to December 2019 of all patients having constipation after surgery for ARMs. Results: A total of 77 patients were included in the study. The median age was 60 months, and thirty patients were male. Primary diagnoses were rectourethral fistula (26; 33.77%), vestibular fistula (25; 32.47%), perineal fistula/ectopic anus (18; 23.38%), rectovaginal fistula (4; 5.19%) and imperforate anus without fistula (4; 5.19%). Anal stenosis was found in 20 (25.97%) patients, posterior ledge with an adequate anal opening in 5 (6.49%), displaced anus in 4 (5.19%) but no obvious problem found in 48 (62.34%) patients. Non-operative management was successful in 75.44% (43 out of 57) of patients. Surgery was performed in 32 out of 77 patients (41.56%) with no mortality. Forty-three (72.88%) patients are continent, stayed clean, but 16 (27.19%) patients still need some sort of laxative/bowel wash/enema intermittently (Grade I/II constipation). Incidence of constipation was higher in patients operated through anterior sagittal route (27.58%) than posterior sagittal route (23.94%), but it was not statistically significant (P = 0.479). Follow-up ranged from 3 months to 5 years. Conclusion: Constipation is a common problem after ARMs surgery, especially in patients having preserved rectosigmoid after pull-down surgery. It is advisable to create relatively larger neoanus after pull through with early practice of neoanus dilatation, especially in redo cases. Repeated counselling, laxatives and dietary manipulations should begin at the first sign of constipation.

Context: While most of the females with anorectal malformations (ARMs) present in either neonatal period or early infancy, a small percentage presents in their adolescence. Aim: The aim is to study the causes of delay in presentation, management, and postoperative outcome in these cases. Settings and Design: This is a retrospective observational study conducted in the Department of Paediatric Surgery, King George's Medical University, Lucknow. Subjects and Methods: Records of females with ARM managed in one unit of the department from 2010 to 2015 were scrutinized. Of these, record of females who primarily presented in adolescence was reviewed. Data regarding the demographics, clinicoradiological presentation, management, postoperative stay, and follow-up were analyzed. Causes for delay in presentation were looked for. Statistical Analysis Used: Statistical analysis used was not required. Results: Out of 627 cases of ARM managed over 5 years, ten girls (5.3%) presented between 12 and 18 years (average 14.4 years). Main reasons for the delay in presentation were misinformation, illiteracy, and poverty. These comprised of anovestibular fistula (n = 5), anterior ectopic anus (n = 3), perineal canal (n = 1), and rectovestibular fistula (n = 1). Three (30%) girls had no problem apart from an abnormal anal orifice. Five (50%) girls had constipation as a major additional symptom. Four cases had a normal to mildly enlarged rectum on contrast study, whereas the rectum was moderately to hugely dilated in the remaining six cases. Six cases were managed with posterior sagittal anorectoplasty while an anterior sagittal anorectoplasty was done in four. Minor wound dehiscence developed in two cases. There was no mortality. In a mean follow-up of 16 months (8–26), constipation and soiling were seen in 5 (50%) girls. The overall outcome in these girls was satisfactory. Conclusion: Presentation of females with ARM in adolescence is not uncommon in the third world. A primary pull through is possible in these girls with mild-to-moderate rectal dilatations. A diverting colostomy before pull through is always a safe option in cases with severely dilated rectum and also otherwise. Moreover, a greater awareness regarding these malformations in the general public is required.

Anteriorly displaced anus is an anomaly that is debated with regard to its nomenclature, diagnosis and management. To describe MRI anatomy of the anal canal in children with anteriorly displaced anus and its impact on the process of defecation. We prospectively examined ten children (7 girls, 3 boys; age range 7 months to 8 years, mean 3 years) with anteriorly displaced anus between August 2009 and April 2012. Noncontrast MRI examinations were performed on a 1.5-T magnet. T1- and T2-weighted turbo spin-echo images were acquired in axial, sagittal and coronal planes of the pelvis. The anorectal angle and the relative hiatal distance were measured in mid-sagittal images, and compared with those of a control group using the Mann–Whitney test. In children with anteriorly displaced anus, no anatomical abnormality was depicted at the level of the proximal anal canal. However, the distal anal canal was displaced anteriorly, running out its external muscle cuff, which remained un-displaced at the usual site of the anus. This changes the orientation of the central axis of the anal canal by passing across instead of along the fibers of the longitudinal muscle coat. Children with anteriorly displaced anus had a more obtuse anorectal angle (mean 112.1°), which was significantly greater than that of the control group (mean 86.2°). MRI is a valuable tool in studying the anatomy of the anal canal in children with anteriorly displaced anus. The abnormal orientation of the longitudinal muscle across the anal canal can explain the obstructed defecation in these children. Based on this study, it might be of interest to use MRI in studying equivocal cases and children with unexplained constipation.

Congenital H-type fistula is a rare congenital rectourogenital connection with an external anal opening in a normal or ectopic position. A systematic review was done to study the anatomical types of congenital H-type fistula, embryology, clinical presentation, relative gender distribution, associated anomalies, investigative modalities, and recent advances in treatment of these lesions. A PubMed search included H-type anorectal malformation; H-type anorectal malformations; H-type anorectal; and H-type congenital anorectal that gave 9;43;76;26 abstracts, respectively. Relevant studies and cited articles were studied omitting duplicate search. The reported incidence is 0.1–16 % of all anorectal malformation. The H-type anorectal malformation is 2.5–6 times more common in females and usually associated with a normal anus. In males, the anomaly is usually a variant with an ectopic anus or a perineal fistula. Anatomical types include anovestibular; rectovestibular; rectovaginal fistula in females and rectourethral (bulbar, prostatic, bladder neck) and rectovesical fistula in males. Variants identified include H-type fistula with perineal fistula, perineal groove, H-type sinus, H-type canal, and acquired H-type fistula. This review compiles the available literature over last six decades. Various surgical corrective procedures have been described. The high recurrence decreases with a learning curve and experience.

We describe a baby girl of 4,000 g and 55 cm with supernumerary, malformed, and partially duplicated lower limbs, malformed and partially duplicated pelvis, spina bifida, coccygeal dermal sinus, ectopic anus located in the right buttock, duplicated internal genitalia, rectovaginal fistula, ileal atresia, Meckel diverticulum, and various renal system anomalies. We think that this phenotype is a new case of disorganization in humans (DsH) and postulate that this condition constitutes a polytopic defect of the blastogenesis. In this case, the presence of a malformation pattern involving structures in different parts of the body and organs derived from all of the germ layers, suggests that the pathogenetic event most probably occurred during blastogenesis affecting various progenitors fields.

There are several totally different definitions of the so-called ectopic anus. To determine whether computerized eight-channel manometry helps to define the entity of the ectopic anus, ten patients (nine females) were operated upon for an ectopic anus by the anal transposition technique (perineal pull-through procedure). Besides the software-supported manometric data, the qualitative imaging analysis was of interest. We calculated the factor by which the pressure of the three ventrally-located segments was lower than the mean segmental pressure at this part of the anal canal. The results were compared to standard age-related values established in a former study in 100 children. Besides pre- and postoperative manometry, barium roentgenograms were obtained. The anal-canal length at rest in the ectopic anus was significantly (P < 0.0001) longer. The segmental asymmetry index in the lower anal canal (LAC) was increased, but not significantly. The pressure in the ventral segments of the LAC was significantly (P < 0.0001) decreased and was less than one-half of the mean segmental pressure in this zone. We found a significant correlation between the degree of anterior displacement and the factor by which the ventrally-located pressure values were decreased. Postoperatively, this factor increased significantly. From a functional point of view, the definition of the ectopic anus includes a deficient high-pressure zone ventrally in the LAC. The LAC seems to run out or nearly out of the ventral sphincteric issue to end ectopically on the perineal surface.

Perineal ectopic anus in female infants is not a very uncommon congenital anorectal anomaly with opening into the low vaginal or vulvar region. However, ectopic anus with barrel gun perineum is a less common variety. Patients generally present with frequent history of constipation, but may seek medical help for just aesthetic reasons. We present here one such case of an asymptomatic seven years old female with the rare form of anterior ectopic anus with barrel gun perineum without any fistulous communications with an innovative method of demonstration of the anomaly by using ultrasound gel as rectal contrast in MRI pelvis.

Ectopic anus is an atypical uncommon variant of broad spectrum of anorectal malformation. We present a case of a 22 day old neonate with anus placed within scrotum. After surgical intervention a neoanus was created within sphincter complex and good functional result was achieved. Patient had urethral injury intraoperatively which was managed by urethrostomy. Subcoronal hypospadias and urethrostomy was corrected in second setting.

Background/Purpose: Perineal ectopic anus in female infants is not a very uncommon congenital anomaly. The close proximity of the ectopic anus with the vulva and the stenosed opening seen in large majority of cases necessitate some form of surgical correction. A variety of surgical procedures like cutback, posterior anal transposition, PSARP, or ASAPR, with or without diverting colostomy have been described in the literature. However, in dealing with a case of ectopic anus, the authors thought a much simpler surgical correction would suffice giving an aesthetically and functionally acceptable perineum. This new and simple surgical procedure developed by Ashok Shah, Anal Shift is described in this report. Methods: Twelve female infants with anterior ectopic anus, between 3 and 18 months of age who had undergone surgical correction by this new method (Anal Shift) is reported. Five of these children had severe and 2 had mild anal stenosis. The new technique described in detail includes shifting and creation of a new anus in the anatomically normal site and construction of the perineal body. Colostomy was not done in any of them. Results: The cases had been followed up for 12 to 24 months. Anal function was normal with satisfactory vulvo-anal distance without any stenosis. One patient had superficial anterior wound dehiscence; she underwent reoperation with good results. Conclusions: Anal Shift is a simple surgical procedure. It does not necessitate lateral dissection, therefore, the rectal support and the neurovascular supply to the rectum remains undisturbed, eliminating any chance of retraction. The anterior half of the neoanus does not have a suture line, thereby minimizing the chances of stricture formation. Anal Shift appears to be a safe, simple and satisfactory surgical procedure to correct anterior ectopic anus in girls without a colostomy. J Pediatr Surg 38:196-198. Copyright 2003, Elsevier Science (USA). All rights reserved.

Disorders of sex differentiation (DSD) are a heterogeneous and broad spectrum group of diseases with a varied appearance. Presence of an accessory phallus with a phallic urethra in association with a normal vagina in a female is an extremely uncommon anomaly. We present a rare case of a genotypically female child with a normal urethra and vagina in association with a phallus, accessory phallic urethra, perineal lipoma and anterior ectopic anus.

Purpose: The aim of the current study was to bring to notice the anterior displacement of the anus and to recommend the measurement of anal position index in the neonate by a modified method. Methods: Sixty newborns (34 girls and 26 boys) were taken into study, and the anal position index (API), which is the ratio of anus-fourchette (scrotum) distance to coccyx fourchette (scrotum) distance, was measured. To obtain the measurement, a transparent adhesive tape was placed along the midline on the long axis, covering the anus. The upper and lower tips and the center of the anal circle was marked and measured using a caliber. Results: API was found as 0.46 (SD ± 0.08) and 0.53 (SD ± 0.05) in female and male neonates, respectively. Because an index of 0.34 in girls and 0.46 in boys are considered abnormal, the 3 female babies in the study group with API indices of 0.18, 0.28, and 0.33 were subjected to further examination. The abnormality was seen not to be rare in the Aegean region. Conclusions: An abnormal index alone cannot be the sole cause of constipation mentioned in the literature and therefore not an indication for operation. Anal position index in the neonates could be measured more accurately by the current modified method. If an anterior location of the anus is found early in infancy the baby should undergo follow-up accordingly. J Pediatr Surg 37:80-82. Copyright © 2002 by W.B. Saunders Company.

We report 5 newborns with a contracted lesser pelvis, imperforate anus (severely stenotic and ectopic anus in 1 case), absent or rudimentary urinary tract, and defective or absent external genitalia, vagina, and uterus but normal gonads. The first 2 patients had small pelvic outlet syndrome (SPOS). The findings in the third patient, a possible transition to sirenomelia, were more severe and included malposition of the penis to the posterior sacral area. The fourth and fifth patients had sirenomelia. The remarkable similarity of many abnormalities observed in these cases and related material in the literature suggests that SPOS and sirenomelia may be part of the same malformation complex (SPOS/sirenomelia complex).

Different criteria have been used in literature to describe the anterior ectopic anus (AEA) anomaly, resulting in uncertainty over its prevalence, association with constipation and definition of the indications for surgery. It has been recently proposed that the term AEA should be restricted to anomalies in which a normal appearing anal orifice is located in the perineum in a more anterior location than normal, with an anal canal of normal calibre that is shown by electrical stimulation to be surrounded by the voluntary external anal sphincter (EAS). We report about four infants, three females and one male, who presented with constipation and had an anteriorly located anal orifice of normal calibre. The anal position index measured clinically was less than 0.34 in all the female patients and 0.44 in the male patient. In preoperative magnetic resonance imaging (MRI), the EAS was distributed all around the circumference of the anal canal, including the ventral aspect of the anal canal, in all the patients. Preoperative MRI documentation of sphincter distribution is recommended for the diagnosis of AEA, as it would help in better definition of its association with constipation and the results of surgical management.

Background: The purpose of this study was to determine the normal position of anus using anal position index (API) and the modified measurement method and also to emphasize the importance of ectopic anus. Methods: This cross-sectional study was performed on 400 neonates, equally boys and girls, who were all full term and delivered without any malformations. Anal position index, which is the ratio of anus-fourschette distance in girls and anus-scrotum distance in boys to the distance between coccyx and fourschette/scrotum, was calculated in all cases. To make correct measurements, transparent adhesive tape was used longitudinally on midperinum in a way that it covered the anus. Then fourschette/scrotum, anus center, and the lower margin of coccyx were marked on it. Distances marked on each tape were then measured with the standard ruler. Results: Mean±SD of API in girls was 0.45±0.005 (95%CI: 0.44-0.46) and in boys was 0.54±0.005 (95% CI: 0. 53-0.55). Mean±2SD was considered as the normal range for an anus position. Six female and five male neonates who had abnormal APIs were put through more investigations. Conclusion: Our findings suggest a simple method for determination of normal position of anus in children; especially those who referred for chronic constipation. API can never be considered as the sole indication for the surgical intervention.

Currarino triad is a rare hereditary disease. The complete form is characterized by the presence of an anorectal malformation, usually anorectal stenosis, a presacral mass and sacral bony defect. The main symptom is the presence of constipation since early life. In over 80 % of cases, the syndrome is diagnosed during the first decade of life. We report on three patients, members of the same family, with the complete form of the syndrome. The main symptom in our patients was intense constipation and the common clinical finding was an ectopic and stenotic anus. In two of them, father and son, the presacral masses were not diagnosed at the time of previous unsuccessful operations in another hospital for correction of the ectopic anus. In the third patient, Currarino syndrome was associated with Hirschsprung's disease. This has not been described previously. Two of the three patients who were admitted in our institution for simultaneous excision of the presacral mass and correction of the anorectal malformation through a posterior midsagittal coccygo-perineal approach, are free of symptoms. To the authors' knowledge, this is the second report of complete Currarino triad in all affected members of the same family.

Anterior displacement of the anus (ADA), otherwise known as "anterior ectopic anus," is considered to be a common congenital abnormality of anorectal region. However, the true incidence of this condition is not well known. We evaluated the incidence of ADA and its relationship to constipation in 357 children (191 boys and 166 girls) who were admitted to our hospital with unrelated disorders. For this purpose, the anal index was defined as the ratio of the scroto-anal distance to the scroto-coccygeal distance in boys, and as the ratio of the fourchette-anal distance to the fourchette-coccygeal distance in girls. An anal index of less than 0.34 in girls and less than 0.46 in boys was determined to be an ADA. The incidence of ADA was 43.4% in girls and 24.6% in boys (P < 0.01). However, the incidence of constipation in children with a normal anal index and those with a low anal index indicative of an ADA was not significantly different. These findings suggest that ADA is a common variant of the normal anatomical location of the anus, especially in girls.

A female patient of 26 years of age with faecal incontinence is presented. The anal opening was anteriorly located just posterior to the vagina. This had resulted in overflow faecal incontinence due to severe chronic constipation. NMR showed a normal musculature of the pelvic floor and sphincter. Since the patient did not agree to surgery, laparoscopic cecostomy was performed for the first time for antegrade rinsing.

A 25-year-old nulliparous woman with adult onset constipation and slight anterior displacement of the anus underwent pelvic magnetic resonance imaging and was diagnosed with congenital hemiabsence of the levator ani sling. Impaired defecation was confirmed by anorectal function studies and defecography demonstrated an anterior rectocele, perineal descent at the upper limit of normal, and partial obstruction of defecation, which appeared related to the levator sling abnormality. To our knowledge, this combination of findings has not been previously described as a cause of adult onset constipation.

WOS: A1996VM28500033 PubMed: 8906688 A case of a gluteus-localized ectopic anus on the right side is described. A P-month-old boy had a severe sacral anomaly with atrophy of the right lower extremity and a pes equinus deformity. Transcutaneous muscle stimulation showed a well-developed muscle complex, and parasagittal muscle fibers have been localized obliquely. Although he has severe sacral anomalies, the posterior sagittal anorectoplasty procedure could be performed. This unique case provides a good demonstration of not only the ectopically localized anus but also the ectopically localized muscle complex. Copyright (C) 1996 by W.B. Saunders Company

Anorectal Malformation (ARM) and Hirschsprung’s Disease (HD) are common causes of congenital intestinal obstruction in children. Simultaneous occurrence of both conditions is rare. Few have been reported in Europe and Asia, but we have no knowledge so far of such report from Nigeria. We present two patients managed in our centre to highlight the challenges of management of this uncommon coexistence. The first patient was a 5-year-old girl who was referred to us with intestinal obstructive symptoms despite an apparently adequate sized ectopic anus. She had colostomy and rectal biopsy, which confirmed HD. She had corrective surgery performed through a posterior sagittal approach. She did well post operatively. The second patient was a 3-year-old girl who presented with features of intestinal obstruction, had laparatomy and was also referred to us. It was observed in the referral hospital during laparatomy, to have features of HD and rectal atresia intraoperatively. She had colostomy done and rectal biopsy performed at the same time, which confirmed the diagnosis of HD. She had simultaneous correction of both conditions through a posterior sagittal approach. She was in good condition at follow up. It was therefore recommended that a high index of suspicion of HD, should be entertained while managing patients with anorectal malformation.Key words: Anorectal malformation, Hirschsprung’s disease, posterior sagittal approach

The purpose of this study was to determine by MR imaging the prevalence and types of dysraphic abnormalities of the spinal cord (i.e., myelodysplasias) associated with urogenital and anorectal malformations of childhood.Since 1987, 92 patients with imperforate anus complex, cloacal malformation, and cloacal exstrophy have had MR imaging as a screening examination for occult dysraphic myelodysplasia. The prevalence and types of myelodysplasia were determined for each group.The prevalence of dysraphic myelodysplasia in each group of children was 17% (1/6) for low imperforate anus (ectopic anus), 34% (11/32) for high imperforate anus (with fistulization), 46% (19/41) for cloacal malformation, and 100% (13/13) for cloacal exstrophy. The most common abnormalities in each group were tethered cord with intradural or filar lipoma in imperforate anus; low-placed or dysplastic conus medullaris and tethered cord with lipoma or myelolipoma in cloacal malformation; and lipomyelocele, lipomyelomeningocele, or lipomyelocystocele in cloacal exstrophy.Our results show that the prevalence of myelodysplasia as seen on MR imaging is high in patients with urogenital and anorectal anomalies.

For the past several years an increasing number of children with either isolated or multiple congenital anomalies have been admitted at the Intensive Care Unit of the University Children's Hospital in Skopje. This kind of patients always poses a challenge to our team regarding the maintainingof stable vital functions, aswell as the genetic diagnosis and counseling in order to predict subsequent healthy descendant in such families. The on-time recognition, diagnosis and early proper treatment directly affects the survival rate in this group of vulnerable newborns and extends their possibilities of better quality of life as well. We are reporting a case of uncommonly seen association of esophageal atresia with tracheoesophageal fistula along with urogenital sinus, anal atresia and ectopic anus that drains into the sinus (cloaca).

Embryologically a fistula in an anorectal malformation can be regarded as an ectopic anus. Since 1984 the so-called fistula has been saved and used as the new anal canal in the surgical reconstruction of 48 patients with high or intermediate imperforate anus. A positive rectoanal inhibitory reflex indicating internal sphincter function was recorded in 32 of 43 patients investigated with anorectal manometry. These patients showed significantly better anal continence. It is concluded that there is an internal sphincter "anlage" in the fistulous connection from the bowel to the urogenital tract. Internal sphincter function can be obtained in the majority of the patients, which seems advantageous for their anal function.

A method of posterior transposition of anterior ectopic anus is described in which the ectopic anus is incorporated in one flap of a Z-plasty. When the flaps are transposed the anus is brought into its normal anatomical position with the added advantages that the mucocutaneous junction and part of the innervation and the blood supply are preserved. The results of 24 girls treated with this technique are presented. In spite of a high incidence of sepsis resulting from less than ideal operative conditions, the repair remained intact.

Anterior displacement of a normal anus is recognized as a cause of severe constipation in some children. We have reviewed our experience with 13 children treated for this disorder over the past 8 years at the University of Virginia Health Sciences Center. Twelve of the patients were female and the age at the time of operation ranged between 12 months and 9 years. In all patients constipation began in the first 3 to 6 months of life. Symptoms were characterized by marked straining upon passage of stool, often accompanied by perineal pain. All patients had been unsuccessfully treated with agressive use of stool softeners and cathartics. The anus had a normal appearance, although it was located anterior to its normal position in every case. There was no evidence of anal stenosis on digital examination; in each case a large posterior rectal cul-de-sac could be palpated. A barium enema examination disclosed a prominent posterior shelf of the rectum, often with enormous dilation of the colon posteriorly. All patients underwent surgical treatment using a posterior anoplasty with advancement of the posterior rectal wall. In 10 patients a posterior rectal myomectomy was added to the procedure. Pathologic evaluation of the rectal muscle was normal in each instance. Complete relief of constipation was achieved in all patients, with follow-up extending for as long as 6 years. One patient continues to require occasional use of stool softeners. Anterior displacement of the anus is a frequently overlooked, although easily corrected, cause of severe constipation in childhood.

In our experience, anterior ectopic anus (AEA) is a common cause of constipation in children. We have performed 54 anoplasties for AEA in the past 8 years. Seventy-eight percent of the patients were girls. The average age at surgery was 23.8 months and the average stool frequency prior to surgery was once every 3.2 days. Eighty percent of the children had undergone attempts at medical therapy. We compared the functional results of anoplasty in children by age. The children who had surgery prior to the age of 6 months had a significantly better outcome than did older children. These data suggest that patients with AEA have a better response to operative therapy when anoplasty is performed prior to 6 months of age. Early recognition, referral, and surgery is appropriate therapy in this patient group.

We report two cases of sequestration of a segment of intestinal mucosa in the perineal area. In one patient this was associated with a mildly ectopic anus. No abnormalities were identified in the bladder, urethra, vagina, or rectum. The lesions were treated by excision following complete anatomical mapping.

Slight anterior displacement of the anus is a common developmental abnormality that represents the mild end of the imperforate anus spectrum. This malformation is a common cause of constipation. This type of constipation can be cured by posterior anoplasty. An experience is described in 134 cases who were operated upon from 1960 through 1977.

The knowledge of sphincter anatomy in anorectal malformations is still inadequate and contradictory. There-fore, morphologic investigations were carried out in 33 neonatal piglets with congenital anal atresias. Of the 24 male animals 12 had high anomalies with a rectourethral fistula. The remaining 12 piglets had low anomalies; in nine cases we were able to demonstrate an anocutaneous fistula. Of the nine female animals, six had high anomalies with a rectovaginal fistula. The three female piglets with low anomalies had an anovestibular or an anocutaneous fistula. In all animals we could demonstrate a normal internal sphincter, which surrounded the proximal part of the fistulae. The position of the internal sphincter there-fore depended on the localization of the fistula orifice into the rectal pouch. This differed greatly. The form of the internal sphincter also differed greatly. Sometimes the muscle had the form of a tube or an acute-angled funnel as in healthy piglets. However, mostly the internal sphincter was spread out wide and had the form of a disc or a flat dish. The proximal region of the fistulae in anal atresias has most features of a normal anal opening: (1) it is surrounded by an internal sphincter, (2) the rectal pouch in the region of the internal sphincter as well as the fistulae are hypoganlionotic, (3) the proximal fistula region is lined by transitional epithelium, and (4) it contains anal glands. We, therefore, consider that the fistula should be designated as an ectopic anal canal. The most important result was the demonstration of a normal internal sphincter even in high and intermediate anomalies of anal atresias. Better postoperative results with regard to continence in high and intermediate anomalies can be attained if this most important sphincter muscle, which is ignored in anal atresias, is integrated in a surgical concept.

Four cases of adult ectopic anus are described. All patients presented with incontinence; in two there was a history of constipation. Electromyography correctly identified the site of the anal sphincters pre-operatively. The anorectum was mobilized and re-routed through the sphincter ring with repair of the perineal body. There was improvement in anal canal pressures on voluntary contraction after operation in all three cases studied. Continence was restored in three patients but results were poor in one patient because of persistent constipation. Severe constipation may be a contra-indication to this procedure.

Anteriorly Placed Rectal Opening in the Perineum “Ectopic Anus” Alexander Bill;R. Johnson;Ralph Foster; Annals of Surgery

Imperforate anusis a broad term applied to various obstructive malformations of the terminal bowel. Most lesions to which it is applied, however, are obviously not imperforate. An increased proportion of cases of “imperforate anus” are being described as having a “fistula,” as more comprehensive studies of the roentgen and surgical pathology are published. Numerous authors (3–5, 10, 14) who have reported large series of imperforate anus in infants all emphasize the fact that one must be prepared to find a “fistula.” Bill (1) found such a “fistula” in 64 of 68 infants with imperforate anus. He believes it should appropriately be called an “ectopic anus.” Gans and Friedman (7) made histopathological sections of these “fistulous tracts,” finding them to be lined in part by transitional epithelium identical to that of the normal anorectal canal, supporting Bill's concept of an ectopic anus. The site of an ectopic anus is the most important aspect to investigate as it usually determines the surgical procedure ...

Ectopic anus in eight patients was assessed functionally by means of electromanometric and electromyographic techniques. These methods safely and adequately distinguish a functional ectopic anus from a fistula. In all cases presented, the internal anal sphincter was found to surround the ectopic anal canal. The normal connections between the rectum and internal sphincter and the rectum and external sphincter were conserved after anal transplantation in two patients. The path of the rectoanal reflex seems to be localized in the anorectal wall.

This is a very rare malformation, in which the vaginal or urogenital sinus opening is placed posteriorly, close to the anus. One might say that it is the anatomic counterpart to the anteriorly placed anus, though it has a different embryology. To date we have seen only three instances of this malformation. Corrective surgery may be undertaken immediately after the neonatal period in children who have done well for 3–4 weeks, i.e., around the 6th–8th week of life. The surgical technique is similar to that for correcting the ectopic anus, but “reversed” (Fig. 23).

The "cutback" procedure has been widely utilized over the past 25 years for correction of mild forms of ectopic anus encountered in newborn females. As these children have become adolescents, some are troubled by the cosmetic appearance created by this procedure, recurrent urinary tract infections, and persistent vaginitis from continued fecal soiling. The rectovaginal separation procedure described (1) separates the rectum from the vagina by interposing adjacent tissues, (2) elongates the rectal canal, and (3) utilizes flaps of perineal skin to gain a normal degree of separation of the anus from the vagina. Five girls, ages 6 to 15 years, have undergone this procedure with a temporary loop colostomy to protect the perineum during healing. The long-term functional and cosmetic results three to seven years later have been excellent in four patients. The fifth girl has been observed only five months, but seems to have an excellent cosmetic result.

In high, combined vaginorectal malformations involving rectal atresia with a vaginal fistula, direct surgery of the vagina is not necessary and the fistula is simply underrun and tied as part of a sacral-perineal-abdominal submucosal rectal pullthrough. With a low rectovaginal malformation, on the other hand, direct vaginal surgery is performed according to the technique described below.

The current classification of congenital anorectal anomalies was established by Partridge and Gough, 1 who divided them into two principal groups: low abnormalities, in which the termination of the bowel is below the pelvic floor (covered anus, ectopic anus, stenosed anus, anal membrane); and high abnormalities, in which the termination of the bowel is above the pelvic floor (anorectal agenesis, with or without fistula, rectal atresia, cloaca, multiple abnormalities). In their discussion of the development of this region, they said of Wood-Jones's theory (q.v. infra), It might be reasonable to suggest that if (it) were true, one might occasionally find a rectourethral or rectovesical fistula without anorectal agenesis. This is not recorded. The case described in this paper is the equivalent of such an anomaly in a female. Sitkovskii 2 reports six similar cases seen in 17 years at the Moscow Central Pediatric Clinic. He describes one case in which

Five male infants are described with imperforate anus with external signs of a low lesion but with subsequent evidence of a higher lesion with demonstration of a fistula into the anterior urethra either at surgery or by radiographic studies. The cases should be considered an intermediate form of imperforate anus with external signs of a low lesion but with fistula characteristically to the membranous or bulbous urethra. These infants should be treated surgically as high lesions with initial diverting colostomies.

The incidence and significance of associated genitourinary abnormalities was reviewed in a series of 484 infants with imperforate anus encountered over a 17-year period. Fourteen percent of the entire series had significant bilateral upper tract urinary abnormalities (either asymmetric or symmetric). Of 67 such patients only 14 had combinations of renal agenesis and hypoplasia-dysplasia representing uncorrectable renal pathology. A high incidence of vesicoureteral reflex and neurovesical dysfunction represent additional important sources of preventable renal deterioration.