Differential sphincteric studies in the diagnosis of ano-rectal disorders of childhood

Pioneering women in American pediatric surgery

Women were among the pioneers in American pediatric surgery in its early decades. Once in practice, Benjy Brooks (Houston) and Jessie Ternberg (St. Louis) became identified with the specialty in their adopted communities, and Rowena Spencer in her hometown of New Orleans. Louise Schnaufer in Philadelphia, Kathryn Anderson in Washington, D.C., and Patricia Donahoe in Boston were all prominent surgeons at leading children's specialty hospitals in the country. Schnaufer was the unsung stalwart in general and thoracic surgery at the Children's Hospital of Philadelphia. Anderson became Surgeon-in-Chief in Los Angeles, and later the first woman leader of both professional societies in pediatric surgery as well as first woman President of the American College of Surgeons. Donahoe developed a spectacular academic career and became one of the outstanding surgical scientists in the country. Each faced gender discrimination at several stages of their careers: medical school enrollments that limited spots for women; widespread bias against women training in surgery and pediatric surgery; and the absence of woman role models and mentors. It is instructive and inspiring to review their individual stories that play an important part of the history of the specialty.

Anorectal Manometry May Reduce the Number of Rectal Suction Biopsy Procedures Needed to Diagnose Hirschsprung Disease

OBJECTIVES

The aim of the study was to evaluate whether anorectal manometry (ARM), which is used to test the rectoanal inhibitory reflex (RAIR), is a safe alternative for reducing the number of invasive rectal suction biopsy (RSB) procedures needed to diagnose Hirschsprung disease (HD).

METHODS

Between 2010 and 2017, we prospectively collected the ARM results of 105 patients suspected of having HD. Following the outcome, the patients either underwent additional tests to confirm HD or they were treated conservatively. Primary ARM-based diagnoses were compared with the definitive diagnoses based on the pathology reports and/or clinical follow-ups. Additionally, we analyzed whether modifications to our ARM protocol improved diagnostic accuracy.

RESULTS

The sensitivity of ARM and RSB was comparable (97% vs 97%). The specificity of ARM, performed according to our initial protocol, was significantly lower than that of RSB. After we modified the protocol the difference between the specificity of ARM and RSB was no longer statistically significant (74% vs 84%, respectively, P = 0.260). The negative predictive value of ARM was 100%, while their positive predictive value was significantly lower than that of RSB (56% vs 97%, P < 0.001).

CONCLUSIONS

ARM is a viable screening tool for HD and, provided it is performed properly, it can be used to exclude HD with absolute certainty. By contrast, an absent rectoanal inhibitory reflex on ARM should always be followed by an RSB to confirm the diagnosis of HD. Using ARM as the diagnostic of first choice could reduce the number of invasive biopsies.

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.

Modified soave pull-through for Hirschsprung's disease: intraoperative internal sphincterotomy

BACKGROUND/PURPOSE

Anorectal achalasia (AA) may persist after pull-through (PT) for Hirschsprung's disease (HD), which may cause postoperative enterocolitis (POE) and constipation. The authors modified the Soave PT (modified Soave PT, MSPT) to eliminate AA, and present their results.

METHODS

This was a 16-year retrospective review of 43 patients with histologically proven HD of the rectosigmoid or sigmoid colon treated by MSPT. The MSPT involves excision of the posterior rectal cuff and an intraoperative internal sphincterotomy, allowing the PT colon to fit nicely.

RESULTS

Mean age at MSPT was 16.7 months (16 were < or =3 months old [37%]; 7 were neonates [16%]). Mean follow-up was 9.2 years. Six of 43 cases (14%) had preoperative enterocolitis; only 2 of 43 (5%) had single episodes of POE. At review, 37 of 43 were older than 4 years; 29 (78%) had normal bowel function (14 had experienced soiling after MSPT, which resolved after a mean of 6.4 years); and 8 (21%) had problematic bowel function: 3 had occasional soiling, 1 had soiling only before defecation, 3 (8%) had constipation requiring laxatives or enemas, and 1 had significant soiling.

CONCLUSION

MSPT is safe and may contribute to a reduction in the incidence of POE and constipation.

Peptidergic innervation of the internal anal sphincter in Hirschsprung's disease

The pathophysiology of the impaired sphincter function in Hirschsprung's disease is still unclear. The peptidergic innervation of the aganglionic large intestine is known to be disturbed. The present study analyzes the peptidergic innervation of the aganglionic internal anal sphincter (IAS) in comparison with that of the circular layer of ganglionic and aganglionic large intestine. Immunoreactivity for the following substances was analyzed: vasoactive intestinal polypeptide (VIP), substance P (SP), met-enkephalin (ENK), calcitonin gene-related peptide (CGRP), somatostatin (SOM), and neuropeptide Y (NPY). All patients were operated upon with Soave's endorectal pull-through technique and a posterior partial myectomy of the IAS. For comparison, specimens of resected IAS from adult patients operated upon for rectal cancer as well as autopsy specimens from a 2-year-old child were analyzed. Differences in the density of nerve fibers between the ganglionic and aganglionic large intestine were in accordance with previous studies. In sections of normoganglionic IAS moderately dense networks of nerve fibers immunoreactive for NPY, SOM, and VIP were observed. The occurrence of NPY and SOM was somewhat more frequent here compared to the colonic circular muscle coat, whereas the opposite was seen for VIP. In aganglionic IAS abundant nerve fibers immunoreactive for NPY, SOM, and VIP were observed. Only a few SP-, CGRP-, and ENK-immunoreactive fibers were found in normal and aganglionic IAS. It is concluded that there were moderate differences in the peptidergic innervation of the aganglionic IAS as compared to the normal ganglionic IAS and the circular muscle coat of the ganglionic and aganglionic large intestine.

Clinical and manometric postoperative evaluation of posterior sagital anorectoplasty (PSARP) in patients with upper and intermediate anorectal malformations

PSARP is currently the most widely-used surgical technique for surgical correction of high and intermediary anorectal malformations, but there is much controversy in the literature about the postoperative evaluation of these cases. We studied 27 cases of anorectal malformations operated with PSARP from clinical and manometric aspects in order to analyze: 1) fecal continence; 2) the relationship between fecal continence and the associated sacral anomalies and; 3) the relationship between the postoperative manometric evaluation and fecal continence. From the analysis of 27 cases of high and intermediary anorectal malformations, we concluded that: 1) fecal continence was achieved in 48.14 percent of the cases; partial fecal continence in 25.92 percent; and fecal incontinence in 25.92 percent of the cases; 2) the presence of fecal incontinence was directly related to the association of sacral anomalies and; 3) anorectal manometry is a useful test to evaluate the patients operated by PSARP, due to the existence of a relationship between the manometric results and the degree of fecal continence.

Anorectal function

A review in a historic perspective of the present knowledge of anorectal physiology is presented. The techniques used in the anorectal physiology laboratory are discussed. Application of new sophisticated techniques to anorectal physiology research in recent years continue to improve our knowledge of anorectal function. Anal continence and defecation depend on both the anal sphincter and the rectum. The assessment of patients with functional anorectal diseases should include a more complete physiologic evaluation of the anorectum than used previously.

Hirschsprung's disease: clinical and experimental observations

Hirschsprung's disease (HD) is a relatively common cause of intestinal obstruction in the newborn. It is characterized by an absence of ganglion cells in the distal bowel beginning at the internal sphincter and extending proximally for varying distances. The etiology of HD-associated enterocolitis remains a complex issue. This study has provided further support for a possible infectious etiology of enterocolitis complicating HD.

The internal anal sphincter: mechanisms of control and its role in maintaining anal continence

The human IAS has particular structural and functional characteristics. This smooth muscle constantly generates rhythmic electrical slow waves, but no action potentials. The slow waves are linked to calcium fluxes and both are essential for mechanical activity, i.e. the ASPW. The IAS is pharmacologically characterized by the presence of alpha excitatory and beta inhibitory adrenergic receptors. Cholinergic drugs have an indirect effect through the release of an inhibitory neurotransmitter, very probably VIP, from NANC nerves. The myogenic activity of the IAS is enhanced by its extrinsic sympathetic innervation. Thus, at rest, the IAS is in a state of partial tetanus and contributes approximately 55% of the MABP. Because the IAS ring cannot be completely closed, the anal mucosa and the haemorrhoidal plexuses fill the gap. By compressing these tissues, the IAS perfectly closes the anal canal to retain not only solids but also fluid stool and gas. Acute rectal distension and rectal activity, mainly through intramural pathways, induce reflex IAS relaxation, permitting the rectal contents to be sampled by receptors in the upper anal canal while continence is temporarily maintained by EAS activity and by expansion of the haemorrhoidal cushions. There is a correlation between the volume of rectal distension and the parameters of IAS relaxation. At maximal IAS relaxation, ASPW are absent, indicating the completeness of the inhibition. Although this RAIR is not essential for defecation, insufficient relaxation may be implicated in constipation. Hyperactivity of the IAS resulting in a high MABP and AUSPW has been considered both as a cause and as an effect in haemorrhoids and anal fissure. Continence for fluids and gas is impaired if IAS activity is decreased (i.e. a low MABP), either by direct trauma or by damage of its sympathetic innervation. Severe faecal incontinence will develop when the contractility of both the IAS and the EAS is affected.

Technical improvement for anorectal manometry in newborns

A modification of the anorectal manometric technique has been devised to improve its accuracy in 31 low-weight newborn and premature infants. The characteristics of the probes used allowed long recording sessions without any sedation of patients. The pressure records fit well the classically accepted requisites. All recordings showed spontaneous fluctuating waves and increased mean pressure in the aboral direction. The anorectal reflex was observed in all cases. Clear reflex waves were recorded in the most caudal third of the anal canal. In this zone the recording showed more distinct features with respect to fluctuation and relaxation waves than those located in more proximal parts. The validity of this technique is unquestionable from the view of the reliability of the recordings independent of the weight, gestational age, and birth age of the infants.

Physiology and pathophysiology of colonic motor activity (2)

The basic motor function of the colon is to mix and knead its contents, propel them slowly in the caudad direction, hold them in the distal colon until defecation, and provide a strong propulsive force during defecation. Infrequently, it also produces mass movements in the proximal colon. These motor functions are achieved in most species by three different types of contractions: the individual phasic contractions that include the short- and long-duration contractions, organized groups of contractions that include the migrating and nonmigrating motor complexes, and special propulsive contractions (giant migrating contractions). The spatial and temporal patterns of all of these contractions are controlled by myogenic, neural, and chemical control mechanisms. The individual phasic contractions are highly disorganized in time and space in the colon. For this reason, they are effective in mixing and kneading and slow distal propulsion. The underlying cause of the disorganization of short duration contractions is the irregularity in the frequency and waveshape of colonic electrical control activity and its phase unlocking throughout the colon. The individual contractions in many species occur in cyclic bursts called contractile states. At least in some species, these contractile states exhibit mostly caudad and sometimes orad migration. However, there are also nonmigrating or randomly migrating contractile states in the colon. These two patterns of contractile states are called colonic migrating motor complexes and colonic nonmigrating motor complexes, respectively. The giant migrating contractions provide the strong propulsive force for defecation and mass movements. The neural control of colonic contractions is organized at three levels--enteric, autonomic, and central. The enteric nervous system contains cholinergic and peptidergic neurons and plays a major role in the control of colonic contractions. The autonomic nerves, the vagi, pelvic, lumbar colonic, hypogastric, and splanchnic nerves, seem to continuously monitor the state of the colon and provide a modulatory input when necessary. These nerves play a major role in the reflexive control of colonic motor function. The voluntary input from the central nervous system coordinates the motor activity of the colon, rectum, anal canal and sphincters for orderly evacuation of feces during defecation. The role of acetylcholine, nonadrenaline, and the yet to be completely identified nonadrenergic, noncholinergic neurotransmitter, possibly VIP, in the control of contractions is fairly well established. Besides these, there are several other peptides and chemicals that are localized in the colonic wall; their physiological roles remain unknown. Colonic motor activity has been studied in several disease states. The findings have not always been consistent.(ABSTRACT TRUNCATED AT 400 WORDS)

Rectoanal reflex induced by H2O thermal stimulation

To obtain clear evidence of the rectoanal reflex, cold water was injected into the rectum. All patients with a normal reflex had a rectoanal reflex when the water was either 4 degrees C or 17 degrees C. The same reflex was seen when a balloon was used for distention. No reflex was evident when the water was 37 degrees C. At 27 degrees C or 45 degrees C, the reflex was evident occasionally. In patients with Hirschsprung's disease, the rectoanal reflex was absent with balloon distention, and when water at any temperature was injected. As cold water will induce the rectoanal reflex safely and without rectal distention, measurement of the reflex using cold water is useful when the presence or absence of the reflex is doubtful. The authors' results suggest that the receptor related to the reflex is neuronal in origin and not muscular, and that the receptor locates near the mucosa.

Distribution and localization of glial fibrillary acidic protein in colons affected by Hirschsprung's disease

The distribution and localization of glial fibrillary acidic (GFA) protein were examined by means of immunohistochemistry in normoganglionic, oligoganglionic, and aganglionic segments of colons from 25 patients with Hirschsprung's disease, including four cases of long segment aganglionosis. In normoganglionic segments, GFA protein-positive glial cells were densely distributed within the myenteric plexus, but sparse in the submucous plexus. Aganglionic segments were completely devoid of glial cells with GFA protein immunoreactivity, coinciding with the lack of enteric ganglia. Instead, GFA protein was found specifically in association with the hypertrophic nerve fasciculi and their branches, which were mainly located in the intermuscular zone and submucosal connective tissue in the distal aganglionic segment of diseased bowels. However, two types of short and long segment aganglionosis differed in the distribution pattern of GFA protein; the extrinsic nerve fasciculi in short segment disease extended toward the normoganglionic segment, but in long segment disease they did not reach this area. A moderate number of GFA protein-positive fasciculi were observed within the circular muscle layer of proximal aganglionic and oligoganglionic parts in short segment aganglionosis, while no immunoreactive fasciculi were encountered within the circular muscle layer of the corresponding parts in long segment aganglionosis. Immunohistochemistry for GFA protein can be of excellent diagnostic value for the aganglionic colon with Hirschsprung's disease, since GFA protein immunohistochemistry discloses exclusively extrinsic, hypertrophic nerve fasciculi, characteristic of the bowel in cases of Hirschsprung's disease.

Studies on the rectoanal reflex in children and in experimental animals: an evaluation of neuronal control of the rectoanal reflex

A single-chamber pressure probe for rectal electromanometry was developed which seems to be superior to the complicated multichamber systems not only for clinical but also for experimental purposes. Measurements of rectoanal reflex were carried out in 268 cases with abnormal bowel function, in 103 cases following operation for Hirschsprung's disease, and in 61 cases of imperforate anus to assess postoperative continence. Experimental studies were performed in 36 dogs, 27 of which were used for short-term and 9 for long-term studies. The results of clinical and experimental studies are described and discussed, with accompanying literature. From clinical and experimental studies, the neuronal pathways of the rectoanal reflex are schematized. The normal rectoanal reflex is mediated by both the sacral cord and the myenteric neurons. It is concluded that measurements of the anal resting pressure and the rectoanal reflex constitute a valuable method to distinguish between normal and pathological sacral and myenteric innervation.

Continence and reflex pressure profile after surgery to correct the imperforate anus

To clarify the cause of constipation which follows surgery for the supralevator type of disorder associated with the imperforate anus, rectal compliance, percentage maximum static anorectal pressure, and reflex profile were measured by anorectal manometry in 108 normal controls and 42 patients. Patients with constipation had a low percentage anorectal pressure (50%), high rectal compliance, associated with megarectum, and defecation of the staining type with constipation due to a reaction in anorectal motility.

Diagnosis of Hirschsprung's disease by anorectal manometry

Anorectal manometry was performed in 48 Japanese children with Hirschsprung's disease and 61 normal children. The resting pressure of the rectum and anal canal was not significantly different between these groups of subjects. The frequency of rhythmical contractions of the anal canal of patients was significantly lower than for the normal subjects, but the frequencies overlapped considerably. Therefore, the frequency is an inadequate indicator for identifying these patients. Conventional manometry elicited a distinct rectoanal relaxation reflex from 90% of the normal children, and the rate increased to 98% when indistinct reflexes were regarded as positive. Indistinct reflexes often occur in neonates, possibly because the constriction of the anal canal is weak. However, when prostaglandin F2 alpha was intravenously administered during the examination, all ambiguous reflexes became distinct. Of patients with Hirschsprung's disease, 4% had a distinct reflex and 19% an atypical one. Most of the atypical reflexes were regarded as being artifacts and were mostly attributed to distension by a balloon. In these patients, the reflex was abolished in case of examination with electric stimulation or stimulation with cold water, procedures which do not dilate the rectum. Moreover these atypical reflexes did not fit the criteria for the normal rectoanal relaxation reflex prepared by the Japan Study Group of Pediatric Intestinal Manometry. The use of electric stimulation, cold water, or intravenously administered prostaglandin F2 alpha improves reliability of the conventional anorectal manometry. A clear and accurate definition of the normal reflex should aid in excluding the atypical reflex.

Manovolumetry: a new method for investigation of anorectal function

A new technique for manovolumetric investigation of rectoanal function allowing for simultaneous recording of rectal volume, anal pressure and external sphincter EMG in response to graded rectal distension was developed. Distension pressure was generated by a water column between two reservoirs. Volume was recorded as shifts of water between the reservoirs. Anal pressure was recorded with a cylindrical balloon and electromyographic activity of the external sphincter by means of a needle electrode. It could be shown that although reduction of preset pressure was minimal, this factor had to be taken into account when rectal compliance is high. The position of the patients during the investigation has to be defined, because rectal volume changed with body position. Pull through studies of anal pressure indicated low sensitivity to displacement of the cylindrical anal probe. A pressure adaptation to the anal probe during eight minutes was noted. Representative recordings of the anorectal response to different isobaric pressures are presented. The present system offers new possibilities for investigation of rectoanal physiology in man.

Assessment of the percentages of maximum static pressure in the anal canal for postoperative continence in patients with imperforate anus

The maximum static pressure in the anal canal was measured using an open-tip manometric method with a continuous infusion system. The values obtained from 49 postoperative patients with imperforate anus were expressed as a percentage of those values obtained from 108 aged-matched controls. The value was observed to be 50 per cent or more in those patients with translevator type, showing normal defecation, 30-50 per cent in those with supralevator type, showing normal defecation or constipation, and 30 per cent or less in those with supralevator type, showing incontinence, and 30 per cent or less in those who had undergone surgery on the anal area at another hospital and required re-operation at our department, showing normal continence or incontinence.

Internal sphincter-saving in imperforate anus with or without fistula. A manometric study

Manometric assessment was performed in 54 infants with congenital ano-rectal anomalies including those with a blindly ending rectum (6 cases) or with an ectopic bowel outlet either in the perineum (25 cases), vulva (8 cases), vagina (8 cases), urethra (5 cases) or bladder (2 cases). Infants with an externally accessible orifice were investigated preoperatively whereas those with an internal orifice or no orifice could only be evaluated after surgical correction. In all operated cases presented, the ectopic rectal opening was preserved together with its surrounding smooth musculature. It was transplanted ventral to the puborectalis sling into the anal dimple if present. A normal functioning internal sphincter was observed in all infants even after transplantation. Anal resting tone was normal in all cases with mean values in the various subgroups ranging from 32 +/- 10 mmHg to 51 +/- 6 mm Hg. Frequency of anal slow pressure wave activity ranged from 11.6 +/- 1.5/min to 15.7 +/- 1.3/min. The recto-anal inhibitory reflex was present in all cases. The term fistula should be reserved for morphologically and physiologically abnormal microscopic communications. Failure to appreciate the presence of a normal internal sphincter may account for poor functional results after surgery. The results demonstrate the importance of preserving the internal sphincter in surgical correction of anorectal anomalies.

High imperforate anus--quantitative results of long-term fecal continence

In a 22-year period, 120 patients were admitted for treatment of a high imperforate anus. Sixty-one patients were available for long-term assessment following a pull-through procedure. These patients were evaluated by written questionnaire and personal interview. Both a qualitative and quantitative fecal continence score were established to provide a system for long-term follow-up that was both reproducible and easy to use. These results were grouped according to the length of time following repair and type of repair performed. Three follow-up time periods were used: 2.5 to 9 years; 10 to 16 years; and 17 to 24 years. During this study, three different procedures were used: sacroperineal (SP), sacroabdominoperineal (SAP), and abdominoperineal (AP). Grouping all three procedures together, the percentage of patients with "good" fecal continence increased in time from 33% to 58% to 64%. Patients undergoing an SP repair uniformly had good results by 10 or more years following repair. In contrast, all patients undergoing an SAP or AP repair had only fair quantitative results 10 to 16 years following repair. Females generally had much better results than males but females also tended to have a lower rectal pouch than males. A comparison of this survey with the results of Swenson, Kiesewetter, Stephens, and Rehbein supports the following conclusions: the anatomic level of rectal pouch at birth predicts fecal continence better than the sex of the patient or type of procedure used; patients in whom the full thickness, terminal rectal wall is used in performing the pull-through procedure have the best fecal continence results.(ABSTRACT TRUNCATED AT 250 WORDS)

Induction of the rectoanal reflex by electric stimulation. A diagnostic aid for Hirschsprung's disease

We induced the rectoanal reflex electrically in three groups of children, following rectal dilatation with a balloon. In normal children, and in children with constipation or ileus due to causes other than Hirschsprung's disease, the rectoanal reflex was induced by electric stimulation as well as by dilatation of the rectum with a balloon. In children with Hirschsprung's disease, however, no typical reflex was obtained by either of these stimuli. Since electric stimulation does not dilate the rectum, passive dilatation of the anus or shift of the probe along with balloon expansion does not take place, so no false-positive reflex is elicited. Electric current, moreover, is capable of providing a constant quantifiable stimulus. We have demonstrated the induction of the rectoanal reflex by electric stimulation alone; distention of the circular muscle of the rectum does not appear necessary for the induction of this reflex.

Manometric diagnosis of Hirschsprung's disease in the neonatal period

A newly designed semiconductor manometer was assembled for anorectal manometry in the neonatal period. Sixty apparently healthy neonates and 17 patients who presented gastrointestinal obstructive symptoms were examined by the eighth day of life. All 60 apparently healthy neonates showed a normal fluctuating wave and rectoanal reflex. Prematurity and postnatal age do not influence the normal rectoanal reflex. Among 17 patients, 5 were diagnosed as having Hirschsprung's disease based on absence of the reflex. There were no false negative or false positive results among these cases. It appears that anorectal manometry could be a reliable diagnostic test of Hirschsprung's disease even in the neonatal period.

An experimental study on the mechanism of rectosphincteric reflex in special reference to Hirschsprung's disease

In order to clarify the mechanism of rectosphincteric reflex (RSR), an experimental study was performed using mongrel canine models. The RSR exists in normal anesthetized mongrel dogs. It does not disappear in dogs with isolation of the rectoanal portion from the surrounding tissues. The RSR disappeared after circular transection of the rectal muscle coat at the level between the rectum and the anal canal, and also after selective destruction of the myenteric plexus of the rectum. These data suggest that the RSR is a local reflex contained within the rectoanal wall and its regulating center and neural pathway are in the myenteric plexus of the rectum.

Assessment of bowel control with anorectal manometry after surgery for anorectal malformation

Bowel function after surgery for anorectal malformation was assessed by Kelly's score in 101 children over 3 years of age. Seventy-two were examined using anorectal manometry. In the "good" group, resting pressure of the anal canal was as high as in the normal children, and the frequency of contraction waves in the anal canal was the same as in the normal children. Recto-anal reflex was recognized in about three fourths of the "good" group. On the other hand, in the "poor" group resting pressure was low, in only one were contraction waves evident and in none was there a recto-anal reflex. The findings of the anorectal manometry placed the "fair" group between the "good" and the "poor" groups. The clear contraction waves of the anal canal or the clear recto-anal reflex related to a resting pressure in the anal canal of over 20 cmH2O. This high pressure in the anal canal is important for good and continence, and depends on a precise pull-through of the rectum into the puborectalis muscle.

Radiologic diagnosis of Hirschsprung's disease utilizing rectosphincteric reflex

Artificial balloon distension of the rectum caused a reflex opening of the anal canal as seen during barium enema in 10 out of 10 normal children and in 7 of 7 children with idiopathic constipation. Reflex opening of the anal canal was not observed in any of 15 children with proven Hirschsprung's disease. This lack of response was independent of the length of aganglionosis or previous diverting colostomy and corresponded to the fact that on manometric study the intraluminal pressure of the anal canal fell in normal children but not in the children with Hirschsprung's disease. This finding greatly improves the reliability of barium enema in the diagnosis of Hirschsprung's disease.

Anorectal manometry results in defecation disorders

Anorectal manometry and suction biopsy were carried out on 47 children with constipation or soiling, or both. Patients were divided into two groups. Group 1 (37 patients): functional faecal retention, group 2 (10 patients): functional faecal soiling without retention. Ganglion cells or normal acetylcholinesterase staining, or both, was demonstrated in all cases. Normal inhibition of internal sphincter could be achieved by rectal distension in all except 2 children with severe constipation. Resting sphincteric pressures, pressure responses, and conscious rectal sensitivity thresholds were similar in groups 1 and 2, but were increased compared with controls. In group 1 alone, the critical volume increased parallel with conscious rectal sensitivity threshold. Since the complete relaxation of internal sphincter occurs before conscious rectal sensation arises in children with soiling without retention, this may be an important factor, at least in some of the soilers.

The manometric evaluation of the rectosphincteric reflex in total colonic aganglionosis

The manometric assessment of rectosphincteric function in 33 patients with histologically proven aganglionosis is reviewed. The age of the patient at first assessment and the presence of total colonic aganglionosis influenced the results obtained. Overall, a 67% accuracy rate was achieved at first assessment. This rate fell to 43% when the test was carried out during the first 7 days of life. Six cases had total colonic aganglionosis. In only a single patient of this group was the first test result positive for aganglionosis. Attention is drawn to this finding.

Quantitative analysis of anorectal pressures in Hirschsprung's disease

Anorectal motility was investigated in 146 children with Hirschsprung's disease and 89 normal control subjects. Pressures were recorded in the rectum and anal canal at rest and during rectal distention. The rectoanal inhibitory reflex was absent in all but four patients. Intraluminal rectal pressure was higher than normal (16.5 vs. 14.6 cm H2O, P less than 0.03), with more frequent (41 per cent vs. 18 per cent, P less than 0.01) pressure waves. In the upper anal canal, there were more frequent (62 per cent vs. 18 per cent, P less than 0.001) spontaneous variations of pressure of lower frequency (9.5 vs. 12.8 cycles/min P less than 0.001) and greater amplitude (5.2 vs. 3.6 cm H2O, P less than 0.001) than normal. The rectoanal contractile reflex occurred in 47 per cent of the patients but in only 21 per cent of the control subjects (P less than 0.001). Aganglionosis was associated with the presence of a rectoanal inhibitory reflex in three patients. This study confirms the value of anorectal manometry in diagnosing Hirschsprung's disease in a large group of patients, and demonstrates other abnormalities that may be useful in cases in which histologic and manometric data are in conflict.

Simple modification of Duhamel's operation for the treatment of Hirschsprung's disease. 11 year results

Surgery was performed in 45 patients with Hirschsprung's disease utilizing our modified Duhamel's procedure. A specifically designed crushing clamp was used to eliminate the development of a blind rectal pouch and the suture line of the retained rectal end. Postoperative complications were relatively rare. Manometric study indicated that most postoperative patients had anorectal function as satisfactory as that of normal control subjects. These results suggest that our modified procedure has great advantages in terms of safety and satisfactory defecatory function for the treatment of Hirschsprung's disease.

Reappraisal of endorectal pull-through procedure. I. Anorectal malformations

Postoperative continence in anorectalmalformations was assessed by clinical score, rectoanal manometry, and electromyography. The results in low deformities operated by perineal rectoplasty showed "good" clinical scores, good preservation of the rectoanal reflex, and good electrical activity of the external sphincter. High deformities, on the other hand, showed low clinical scores, poor recordings of the rectoanal reflex, and diminished electrical activity around the anus. Analysis of high deformities treated by operative procedures, however, indicated better clinical scores and better preservation of rectoanal reflex in those who had undergone the endorectal pull-through procedure (Rehbein) than those who had had an abdominoperineal pull-through procedure. Furthermore, dissections of newborns with a rectourethral fistula revealed the presence of the puborectalis sling around the terminal rectum and fistula in a hammock fashion. This finding supports our suggestion that the colon can be safely pulled-through within the sling by the original Rehbein procedure without sacral dissection.

Postoperative sequential anorectal manometric study of children with Hirschsprung's disease

When the rectum was distended artificially by a balloon, intraluminal pressure in the anal canal dropped in 30 normal children, but rose in 22 children with Hirschsprung's disease. This was independent of the length of aganglionosis. The average resting pressure in the anorectum in Hirschsprung's disease was higher than that of normal children. In patients who underwent coloproctectomy and Z-shaped anastomosis for Hirschsprung's disease, the rectosphincteric reflex was absent 1 mo after operation. Two months after surgery, however, the rectosphincteric reflex appeared in 77% of the patients. The patients who developed a rectosphincteric reflex had excellent continence, while some of those who did not show the reflex had incomplete continence or mild constipation.

Activity of the internal anal sphincter during the first days of life

Manometric recordings of the internal anal sphincter activity are frequently used in the diagnosis of Hirschprung's disease. Normally, there is a relaxation of the internal sphincter in response to a rectal distension, but this is absent in Hirschprung's disease. In order to study the normal physiology during the first days of life, 17 healthy full-term infants were examined daily with ano-rectal manometry during the first four days of life. Resting anal pressure was lower than in older children. Internal sphincter relaxation was recorded in all infants but one on the first day, in all on the second and finally in all but one on the third and fourth days. The results indicate that anorectal manometry may be used in the diagnosis of Hirschprung's disease also in the newborn period. However, repeated examinations may be necessary and the diagnostic reliability may be somewhat lower than in older children.

Diagnosis of Hirschsprung's disease

A prospective study of the accuracy of various diagnostic methods used in the detection of Hirschsprung's disease (syn. congenital intestinal aganglionosis, CIA) in 60 consecutive infants and children was done during the period 1972--76. Every patient underwent a barium enema, a rectal mucosal biopsy, which was prepared for both the demonstration of ganglia and for the assessment of acetylcholinesterase activity (ACE), and anal manometry was performed. In evaluating the clinical history, special emphasis was placed on signs of neonatal ileus. In the group of 10 patients with a definite diagnosis of CIA the results were almost uniform. In the 'non-CIA' group the search for ganglia in biopsy material proved non-confirmatory in nearly half of the cases studied due to the fact that specimens were taken too superficially. The findings pertaining to ACE, barium enema and the results of manometry were at variance or inconclusive of a final diagnosis in 10, 16 and 22% of the performed studies, respectively. The value given to neonatal history proved to be of the same order, i.e., 20% proved to be falsely positive.

Anorectal manometry in premature infants

Twenty-eight unselected premature infants were subjected to anorectal pressure studies, using an infusion manometric technique, with a view to establishing normal parameters in this age group. Satisfactory rectal and sphincter pressure readings were obtained in all but one case. In all of these there was a normal anorectal reflex. Low birth weight and prematurity do no preclude a normal anorectal reflex as measured by this technique.

A manometric assessment of anorectal pressures and its significance in the diagnosis of Hirschsprung's disease and idiopathic megacolon

Anorectal manometric studies were performed on nine patients with Hirschsprung's disease and ten patients with idiopathic megacolon for the purpose of differentiation, comparing with those of the normal subjects. The anorectal reflex was absent in all nine of the patients with Hirschsprung's disease while in all of ten patients with idiopathic megacolon rectal distension produced a relaxation in the anal canal like that of the normal subjects. Manometric studies proved to be a reliable and non-invasive technique for the diagnosis of Hirschsprung's disease and were of particular value as simple screening tests in patients with a clinical suggestion of this disease. The manometric studies of the patients with Hirschsprung's disease or idiopathic megacolon in the present series also demonstrated that the pronounced internal sphincter contraction combined with a total absence of reflex relaxation or an inadequate response of the sphincter to rectal distension might be responsible for the obstructive symptoms in these diseases.

Influence of general anaesthesia on ano-rectal manometry in healthy children

According to several investigations ano-rectal manometry is a valuable diagnostic test of Hirschsprung's disease. In order to yield accurate results it requires a quiet, calm child who cooperates. In the few instances when this is not possible, general anaesthesia may be desirable. Manometric recordings of the internal and sphincter activity were therefore performed in 15 healthy children when awake and during general anaesthesia. The tonic activity at rest was significantly reduced during anaesthesia. Relaxations of the internal sphincter in response to rectal distension were recorded in all children both when awake and during anaesthesia. They were, however, significantly less pronounced during anaesthesia. These findings strongly suggest that ano-rectal manometry in the diagnosis of Hirschsprung's disease may be performed with advantage during general anaesthesia if the child does not cooperate when awake.

Accuracy of the manometric diagnosis of Hirschsprung's disease

In a 3-yr period, 229 examinations were carried out in infants and children. These were sub-divided into five groups according to age. There were 10 false positive and 8 false negative results, an overall not unreasonable record of 7.8% errors. However, in the neonatal group, there were as many as 26% errors and thus the test in this group was considered to be highly inaccurate. The older the infant or child, the less errors in diagnosis occurred. Possible reasons for errors are pointed out and comparisons are made with other series.

Ano-rectal manometry in the diagnosis of Hirschsprung's disease in infants

Manometric recordings of internal sphincter activity were performed during distension of the rectum in 10 healthy control infants and in 9 infants with clinical signs of Hirschsprung's disease. In 8 of the healthy infants relaxations of the internal sphincter were obtained, which were maximal 4 to 7 secs after rectal distension. This was also the case in 5 of the patients who were later proven not to have Hirschsprung's disease. In 3 patients no relaxations of the internal sphincter could be recorded. Subsequent rectal biopsy revealed absence of ganglion cells, confirming the diagnosis Hirschsprung's disease. The remaining 3 infants (2 controls and 1 patient) could not be calmed during the examination and the results were inconclusive. It is concluded that ano-rectal manometry is a valuable method of examination in the diagnosis of Hirschsprung's disease in infants. No false results were obtained in this study. Furthermore, it is an easy procedure without risk or discomfort for the patient.

Control of the internal anal sphincter (manometric study with human subjects)

Manometric studies of the functions of the internal anal sphincter were performed in 73 children. Twenty-one out of these patients were normal subjects, the others had neurological lesions either central (sacral meningocele, dorsal cord transections) or peripheral (Hirschsprung's disease). It was found that the functions of the internal sphincter do not depend upon mechanical factors and are subject to nervous control. The pathways for control of the basal sphincteric tone are discussed. It is likely that this tone depends not only of the sympathetic pathways, but also of fibers of the sacral outflow. It is shown that the recto-anal inhibitory reflex is specific and independent of peristalsis. Arguments are given to prove that this reflex is an activity proper to the intra-mural plexus which is, however, subject to and regulated by the sacral cord.

Anorectal myectomy in treatment of ultrashort segment Hirschsprung's disease. Report of 26 cases

A diagnosis of Hirschsprung's disease should be considered in children with constipation. An accurate neonatal history of bowel function and testing of anorectal pressure responses will aid the diagnosis. In the period 1971-75 inclusive, 140 children, aged 6 months to 14 years, were investigated by anorectal manometry. 26 showed a failed inhibition response to rectal dilatation, suggesting Hirschsprung's disease and were treated by anorectal myectomy. In 24 the disease was confirmed histologically. Two specimens were diagnostically unsuitable. 4 required repeat myectomies, and 3 anterior resection. At follow-up all had normal bowel movements without soiling.

Investigation and management of long-standing chronic constipation in childhood

The anorectal physiology of 106 children with long-standing chronic constipation, who had failed to response to a trial of medical treatment, was assessed. 10 (9%) were shown to have ultrashort-segment Hischsprung's disease, later confirmed on histology, The remainder showed evidence of hypertrophy of the internal sphicter on anorectal manometry and had a vigorous anal dilatation (to accept 4 fingers) under general anesthesia. After this, 38% were able to be weaned off all medication and most of the remainder improved. Further anal dilatation and internal sphincterotomy allowed a further 10 children to stop laxative, bringing the total to 48%.

Manometric studies of anorectal disorders in infancy and childhood: an investigation of the physiopathology of continence and defaecation

Anorectal manometry was performed on 126 infants and children with anorectal dosorders. In addition, 14 normal children were studied. Pressure measurements were taken with two perfused open-tip catheters. The activity of the external and internal balloon was used to distend the rectal ampulla with air.