Psychological evaluation of patients with severe idiopathic constipation: which instrument to use

We prospectively evaluated 38 patients with chronic severe idiopathic constipation who failed to respond to conventional therapy. Colonic transit studies, the Hopkins Symptom Checklist (SCL-90-R), and the Minnesota Multiphasic Personality Inventory (MMPI) were completed. Colonic transit studies identified 23 patients with slow transit and 15 with normal transit. Patients with normal transit constipation scored higher than those with slow transit on every scale of both the SCL-90-R and MMPI, but the SCL-90-R appeared to detect greater differences between the two groups. We conclude that the SCL-90-R is the preferred psychological instrument to evaluate patients with chronic severe constipation who fail to respond to conventional therapy. It provides information similar to the MMPI with which to measure behavioral profiles of patients in an office setting, and it can be completed and scored more rapidly.

[Hemi-arthroplasty of the hip joint: concentric or positive eccentric (self-centering) dual head prosthesis? A retrospective comparison]

In femoral neck fractures in the elderly, the least traumatic operative treatment is hemiarthroplasty. In our Trauma Unit, from August 1986 to December 1986 we implanted 22 concentric bipolar cups. During follow-up this cup proved to be associated with an unjustifiably high failure rate: system-caused interprosthetic dislocation in 4 patients (18%), and extraprosthetic dislocation in a further 3 (13%). In one of the latter, interprosthetic disconnection occurred during closed reduction. In all of these, i.e., in 31% out of the 22 patients, conversion to a total hip arthroplasty became necessary. Since March 1987 we have used a positive eccentric, self-centering bipolar head. Up to September 1990 322 such prostheses were implanted. Bearing in mind the reduced general physical condition of the patients, the complication rate is considered to be low (dislocations 3.4%, conversion to total hip arthroplasty 0.9%, deep wound infections 3.1%).

Comparative studies of esophageal function in systemic sclerosis

Three modalities for assessing esophageal dysfunction in patients with systemic sclerosis were prospectively compared. Seventeen patients underwent (a) esophageal manometry with measurement of distal esophageal peak contraction pressure amplitude, percentage of peristaltic waves, and lower esophageal sphincter pressure; (b) cine-esophagography with scoring based on residual contrast and the character of visualized waves; and (c) esophageal transit scintigraphy with quantification of residual swallowed tracer. Highly significant correlations were found between scintigraphic residual and cine-esophagography score, between scintigraphic residual and manometric amplitude, and indeed between all pairs of measured esophageal function parameters except those involving lower esophageal sphincter pressure. In addition, scintigraphy and cine-esophagography showed comparable ability to discriminate between patients with abnormal and normal esophageal motor function. Symptoms did not significantly correlate with quantitative parameters, nor did they have diagnostic discriminating ability. Induction of Raynaud's phenomenon in a subgroup of patients had no detectable effect on esophageal function. It was concluded that these three diagnostic modalities are approximately equivalent in their ability to detect esophageal dysmotility in systemic sclerosis and measure its severity.

Evacuation proctography in normal volunteers

Constipated patients evaluated by evacuation proctography may be subjected to vigorous medical therapy or surgery, even colectomy, based on radiographic findings that have been called "abnormal" in the literature. Criteria for normal defecography are not uniformly established, nor has correlation of structural or functional findings with symptoms been clearly documented. We prospectively studied 21 asymptomatic volunteers to assess the frequency of findings in a control population, and to establish a quantitative measure of normal rectal emptying. Standard defecography technique demonstrated rectocele, intussusception, pelvic descent, or puborectalis spasm in 14/21 volunteers (67%). The range of rectal emptying was 12.5% to 100%, with four subjects (19%) evacuating less than or equal to 40% of the barium paste. There was no correlation between severity of radiographic findings and degree of evacuation. Defecography results in patients being considered for symptomatic intervention should be interpreted cautiously, given the wide range of normal variation in a control population.

The effect of laboratory stressors on glycemic control and gastrointestinal transit time

This study compared effects of an active coping task (computerized stressors involving arithmetic, anagrams, and Atari games) and a passive coping task (cold pressor) on gastrointestinal transit time and glycemic response to an oral glucose load. Eleven normal weight males were studied; subjects participated in three counterbalanced sessions, each including a 45-minute baseline, 20-minute experimental period (active coping, passive coping, or nonstress control) and 2.5-hour recovery period. The stressors produced different cardiovascular and catecholamine responses; systolic and diastolic blood pressure were highest during cold pressor (p less than 0.001), heart rate was highest during computer stressor (p less than 0.001), and norepinephrine excretion was greatest during cold pressor (p less than 0.002). However, both stressors delayed gastrointestinal transit time compared with the control condition (p less than 0.009 and p less than 0.026 for cold pressor and computerized stressor, respectively) and both delayed the time of peak glucose response (p less than 0.002 and p less than 0.05, respectively). Implications of these findings for patients with diabetes and for effects of stress on eating behavior are discussed.

Anorectal sensory and motor function in neurogenic fecal incontinence. Comparison between multiple sclerosis and diabetes mellitus

We measured anorectal sensory and motor function in 11 patients with multiple sclerosis and fecal incontinence, 11 continent patients with multiple sclerosis, 10 diabetics with fecal incontinence, and 12 healthy control subjects. The threshold volume at which patients with multiple sclerosis and fecal incontinence experienced rectal sensation was higher than that in healthy controls (42.7 +/- 6.2 mL vs. 13.3 +/- 2.8 mL; P less than 0.01) and was similar to that in incontinent diabetics (36.5 +/- 5.7 mL). Patients with multiple sclerosis and incontinent diabetics also showed increased thresholds of phasic external sphincter contraction compared with controls (P less than 0.05). Diabetics with incontinence had reduced resting and maximal voluntary anal sphincter pressures compared with controls (P less than 0.05), whereas patients with multiple sclerosis and incontinence showed only decreased maximal voluntary anal sphincter pressures (P less than 0.01 vs. controls and diabetics). Incontinent patients with multiple sclerosis also required smaller volumes of rectal distention to inhibit internal sphincter tone compared with diabetics and controls (P less than 0.01). Decreased maximal voluntary squeeze pressures were less severe in continent patients with multiple sclerosis than in incontinent patients with multiple sclerosis. We conclude that impaired function of the external anal sphincter and decreased volumes of rectal distention to inhibit the internal anal sphincter or both may contribute to fecal incontinence in multiple sclerosis. In addition, increased thresholds of conscious rectal sensation in some incontinent patients with multiple sclerosis and diabetes mellitus may contribute to fecal incontinence by impairing the recognition of impending defecation.

Constipation and fecal incontinence in the elderly

The successful management of constipation and fecal incontinence in the elderly requires an understanding of colorectal function, careful delineation of the patient's complaint, and in selected patients, specialized studies of colonic and anorectal function. This article reviews (1) the prevalence and nature of lower bowel dysfunction in the elderly population: (2) colonic and anorectal physiologic changes that are associated with aging; (3) the causes, consequences, and approaches to the management of constipation in the elderly; and (4) the causes of fecal incontinence in this age group and the treatment available.

Prevalence of bowel dysfunction in multiple sclerosis. A population survey

An unselected outpatient population of 280 individuals with multiple sclerosis was surveyed to determine the prevalence of bowel dysfunction and to define their characteristics and their relationship to the nongastrointestinal manifestations of the disease. Constipation was present in 43%, was similar in frequency in both sexes, and was more common in patients, regardless of degree of disability, than in a control population. Frequency of constipation also correlated with duration of disease and genitourinary symptoms but did not correlate with use of any medications in mildly disabled patients. Fecal incontinence had occurred at least once in the preceding 3 mo in 51% of patients and once per week or more frequently in 25% of patients who were questioned in more detail with a follow-up questionnaire. Correlations of fecal incontinence with disability, duration of disease, and presence of genitourinary symptoms were similar to constipation. The prevalence of bowel dysfunction (constipation and/or fecal incontinence) in the multiple sclerosis population was 68%, and this manifestation was common even in mildly disabled subjects. Bowel dysfunction can be a source of considerable ongoing social disability in patients with multiple sclerosis. Further studies are needed to characterize the pathophysiology of this common disorder so that effective therapeutic strategies can be identified.

Contributions of evacuation proctography and anorectal manometry to evaluation of adults with constipation and defecatory difficulty

We prospectively evaluated 36 patients who complained of chronic constipation and/or defecatory difficulties to determine the role of anorectal manometry and evacuation proctography in delineating the pathogenesis of these complaints. Twenty patients with constipation also underwent a colonic transit study with radioopaque markers, which identified one group with normal transit (N = 10) and another with slow transit (N = 10). Nine of 36 patients (25%) had inappropriate puborectalis muscle contraction or exhibited weak expulsion efforts during evacuation proctography, and these correlated highly with poor rectal emptying of barium paste (20 +/- 6% vs 61 +/- 5% in patients with normal relaxation; P less than 0.01). However, poor rectal emptying did not correlate with the presence of high-grade intussusceptions, large rectoceles, anorectal angles at rest or with straining, rectal diameter, clinical features, or colonic transit. Moreover, abnormal expulsion patterns as seen with anorectal manometry correlated poorly with the presence of inappropriate puborectalis contraction and decreased rectal emptying by proctography. Although anatomic abnormalities occurred frequently in patients with constipation and/or defecatory difficulties, they were also prevalent in asymptomatic controls. In view of these findings, surgical intervention to correct anatomic abnormalities in patients with constipation and/or defecatory difficulties should be considered only with great caution.

Gastric emptying in patients with bulimia nervosa and anorexia nervosa

A dual radioisotope technique was used to measure gastric emptying of a mixed liquid and solid meal in 11 patients with bulimia nervosa, and was compared with 10 patients with anorexia nervosa and a sex-matched control population. The relationship of body weight and gastrointestinal symptoms to gastric emptying was also examined. Gastric emptying of solids in patients with bulimia nervosa was similar to that in controls (gastric T1/2 131 +/- 15 min vs 119 +/- 7 min; mean +/- SEM). In contrast, patients with anorexia nervosa had overall delayed emptying (182 +/- 31 min; p less than 0.05); six patients had normal emptying of the solid components of the meal and four had markedly delayed emptying. Gastric emptying of liquids was similar in the bulimics and controls (gastric T1/2 48 +/- 5 min and 49 +/- 4 min, respectively), whereas the anorexics tended to have prolonged gastric emptying (65 +/- 11 min, p = NS). There was no correlation between body weight, gastrointestinal symptoms, and gastric emptying in either group. These findings suggest that gastrointestinal symptoms are unreliable indicators of gastric emptying in patients with eating disorders, and that gastric emptying studies should be performed in such patients before treatment with prokinetic agents is considered.

Psychological and physiological characteristics of patients with severe idiopathic constipation

This study prospectively evaluated psychological profiles and selected parameters of colonic and anorectal sensorimotor function in 25 consecutive patients who were referred for severe idiopathic constipation. Measurement of colonic transit of radiopaque markers divided patients into those with normal transit (n = 10) and those with slow transit (n = 15). As measured by the Hopkins Symptom Checklist, patients with normal transit constipation demonstrated significantly higher scores for psychological distress in the global symptoms index and nine clinical subscales than did those with slow transit constipation and gastrointestinal control subjects (n = 25). Both groups with constipation had decreased rectal sensation compared with controls but there was no relationship to rectal compliance or threshold of internal sphincter relaxation. There was also no relation between abnormalities of anorectal parameters, including expulsion dynamics, and psychological profiles in two groups. Measurement of colonic transit and psychological profiles in patients with severe idiopathic constipation identify two groups of patients with respect to possible pathogenesis of symptoms. Accordingly, different therapeutic approaches may be required, one behaviourally and psychologically based and the other focused on the possible modification of disordered colonic transit.

Disorders of defecation and fecal continence

Although fecal incontinence and disorders of defecation are not uncommon, these disorders are poorly understood by most physicians. Successful management requires an understanding of colorectal function, delineation of the problem and potential contributing factors, careful examination of the anorectal and pelvic floor areas, and psychosocial assessment. Specialized studies to evaluate colorectal function frequently help determine patterns of abnormality and may suggest appropriate therapeutic approaches. Therapeutic options include pharmacologic, behavioral, and surgical approaches, which often ameliorate symptoms and dramatically improve quality of life.

Colonic and anorectal dysfunction associated with multiple sclerosis

Gastrointestinal symptoms are common in patients with multiple sclerosis. In a recent survey of 280 unselected patients with multiple sclerosis, 68% reported constipation and/or fecal incontinence. In contrast to bladder dysfunction which has been extensively studied, bowel dysfunction in this disease has received relatively little attention. This review outlines the clinical features and pathophysiology of constipation and fecal incontinence in multiple sclerosis and presents treatment options and suggestions for investigation of colonic and anorectal dysfunction in this population.

Fluorescent light interferes with pulse oximetry

Arterial oxygen saturation (SaO2) values displayed on the pulse oximeter dropped dramatically in 3 children undergoing neurosurgical procedures when a hand-held fluorescent light was used to observe the patients. Pulse rates were unchanged on both the electrocardiograph and pulse oximeter. Electromagnetic interference was excluded as the cause of desaturation. A great deal of energy was emitted by the hand-held light in the 660-nm region, which is one of the wavelengths used by the oximeter. False readings of pulse rate and SaO2 values caused by ambient light could be avoided if oximeter probes were manufactured of black opaque material that does not transmit light or enclosed in an opaque plastic housing.

Does gender or the menstrual cycle affect colonic transit?

Controversy exists as to whether slowing of colonic transit occurs in the high progesterone luteal phase of the menstrual cycle. To clarify this issue, colonic transit studies using radiopaque markers were performed on 10 women in the follicular phase, 10 women in the luteal phase of the menstrual cycle, and five women on oral contraceptives, and the results were compared with transit times in 11 male controls. No significant differences in colonic transit were found between either phase of the menstrual cycle. Colonic transit in women was slower than in men, but this was not statistically significant. In the clinical setting, therefore, colonic transit studies can be performed throughout the menstrual cycle or when taking oral contraceptives. In addition, a single standard for normal values can be used for both men and women.

Influence of gender and menopause on gastric emptying and motility

The aims of this study were to determine (a) if there are differences in gastric emptying rates of a mixed liquid and solid meal between men and women, (b) if menopausal status affects gastric emptying, and (c) whether differences in solid emptying rates are associated with alterations in postprandial antral motility parameters. A dual-isotope technique was used to measure gastric emptying in 20 men, 18 premenopausal women, 14 postmenopausal women, and 8 postmenopausal women taking estrogen and progesterone hormone replacement. A multilumen perfusion catheter was used to measure antral motility in 6 men and 6 premenopausal women. Premenopausal women, postmenopausal women, and postmenopausal women taking oral estrogen and progesterone had slower gastric emptying of liquids than did men (p less than 0.025, less than 0.05, and less than 0.025, respectively). Both premenopausal women and postmenopausal women taking sex hormone replacement therapy had slower emptying of solids than did men (p less than 0.025 and less than 0.05) but, in contrast to liquids, postmenopausal women not on hormone replacement emptied solids at a rate similar to that of men. There were no differences in postprandial antral motility parameters between men and premenopausal women. These findings support the hypothesis that sex steroid hormones have variable inhibitory effects on gastric emptying of a mixed meal and this should be considered when studying gastric emptying in disorders that occur predominantly in premenopausal women.

Ethics and standards in clinical engineering

The historical background of ethical issues in health care, leading to the establishment of standards by governing authorities, is traced. The types of standards and their scopes are examined. The ways in which the clinical engineer is involved with standards are discussed.

Evaluation of biofeedback in childhood encopresis

In order to evaluate the efficacy of biofeedback for childhood encopresis, 50 children with encopresis were prospectively studied and randomized to receive biofeedback (B) or mineral oil therapy (M). Specificity of biofeedback was also evaluated by comparing outcomes of both regimens in children with normal (n = 32) and abnormal (n = 18) defecation patterns. Using a single blinded design, there were no significant differences in clinical outcomes between the 24 children receiving B and the 26 children receiving M at 3, 6, and 12 months. However, at 12 months six of nine children with abnormal defecation patterns were in remission or markedly improved after receiving B, compared to only three of nine children receiving M. In contrast, children with normal patterns appeared to respond better to M than did those receiving B (71 vs. 40% at 12 months). Biofeedback appears to warrant further evaluation in children with encopresis and abnormal defecation patterns.

Normal variation in radionuclide esophageal transit studies

We studied the esophageal transit of aqueous 99mTc-sulfur colloid in 16 normal subjects, 8 of them twice. Condensed dynamic images having a spatial and a temporal dimension fell into four patterns: (1) idealized form, (2) retrograde motion, (3) splitting of the bolus, and (4) generation of a substantial residual component. The retrograde index quantifying retrograde motion in the first swallow (RI), the rapid component mean transit time through the esophagus in the first swallow (MTT), and the residual fractions after the first, second, and fourth swallows [RF(1), RF(2), and RF(4)] were computed. The intrasubject and intersubject variation of the quantitative results suggest that normal subjects have sporadic aberrant swallows with high RI and/or RF(1). RF(2) and RF(4) showed a significant positive correlation with age.

Prevalence of behavior problems and mental health utilization among encopretic children: implications for behavioral pediatrics

The psychiatric literature traditionally has viewed encopretic children as having severe and characteristic behavior problems. Current psychiatric views as expressed in the Diagnostic and Statistical Manual of Mental Disorders, 3rd Edition (DSM-III), and in the pediatric literature, however, tend to regard the behavior problems of encopretic children as being rather mild or secondary to the consequences of the encopresis itself. Using a behavioral checklist with empirically derived factors (the Child Behavior Checklist), 55 children presenting for medical treatment of their encopresis have been assessed. Numerous behavior problems are reported on parental ratings, but the overall severity of behavior problems in this group of children falls below that found in children with behavior problems who are referred for mental health services. Most children presenting for medical management of encopresis have not been seen or evaluated by mental health services. Encopresis is a disorder in which psychological evaluation and intervention by the pediatrician may be advisable.

Utility of fecal fat concentrations as screening test in pancreatic insufficiency

We explored the utility of fecal fat concentration (gram fecal fat per 100 gram wet stool weight) as a screening test for pancreatic steatorrhea. Data were analyzed on 24 patients with pancreatic insufficiency and steatorrhea, six groups of patients (N = 70) with nonpancreatic causes of steatorrhea, and 31 controls without steatorrhea. Patients with pancreatic steatorrhea had significantly (P less than 0.05) higher mean fecal fat concentrations than all groups except for patients with hepatobiliary disease. Using a fecal fat concentration of greater than 9.5% as a cutoff point in all patients with steatorrhea, the test was 41.7% sensitive and 92.0% specific for the diagnosis of pancreatic insufficiency. For patients with fecal fat excretion greater than 20 g/day, the test increased in sensitivity to 61.5% but specificity dropped to 85.3%. Measurements of fecal fat concentrations are therefore only moderately helpful, and further evidence is required to secure a diagnosis of pancreatic steatorrhea.

Colonic transit and anorectal manometry in chronic idiopathic constipation

Twenty-one patients with refractory idiopathic constipation underwent studies of segmental colonic transit of radiopaque markers and anorectal manometry to determine the utility of these tests in planning therapy and in predicting subsequent clinical outcome. Colonic transit studies defined three groups: normal transit (n = 6), colonic inertia (n = 8), and distal slowing (n = 7). Normal transit was universally associated with evidence of psychosocial disturbances. During follow-ups ranging from 23.2 to 26.7 months, six of eight patients with colonic inertia failed to improve compared with only one of seven with distal slowing. Anorectal manometry was useful in excluding abnormalities of anorectal function. Segmental colonic transit of radiopaque markers is a simple and useful test in the evaluation of refractory idiopathic constipation and appears to have both prognostic and therapeutic utility in selected cases.

Fecal incontinence. Effective nonsurgical treatments

Management of the patient with fecal soiling begins with a careful evaluation of possible contributing factors, followed by anorectal examination, neurologic and psychosocial testing, and workup for chronic diarrhea, if present. In many patients, these procedures should be supplemented by radiologic and manometric studies to determine if structural or functional anorectal abnormalities are present. Therapeutic approaches include behavioral, pharmacologic, and surgical methods, which should be carefully considered in relation to the underlying cause of incontinence. For the experienced physician, therapy can be gratifyingly effective in many patients with fecal soiling and can dramatically improve their quality of life.

Celiac sprue complicated by lymphoma presenting with multiple gastric ulcers

A 40-yr-old woman with celiac sprue, which had responded clinically and histologically to gluten elimination, subsequently developed gastrointestinal lymphoma. Although this has been described in the small intestine of patients with celiac sprue, the unique feature in this patient was her initial presentation with multiple gastric ulcers refractory to conventional medical therapy. This case demonstrates that lymphoma complicating celiac sprue may present with multiple refractory gastric ulcers in addition to those occurring in the small intestine.

Anorectal function and continence mechanisms in childhood encopresis

We compared anorectal sensory and motor functions, expulsion dynamics, and continence mechanisms in 50 children with encopresis and 21 healthy control children. When expulsion dynamics were studied, 43% of boys with encopresis inappropriately contracted the muscles near the anal canal compared with 10% of girls with encopresis (p greater than 0.05) and 10% of control children of both sexes (p less than 0.05). In contrast to previous studies we demonstrated no abnormalities of thresholds of conscious rectal sensation or internal anal sphincter relaxation. In addition, children with encopresis had no demonstrable abnormalities of rectosphincteric continence mechanisms or strength of external anal sphincter contraction. We conclude that a significant number of boys with encopresis have abnormal anorectal expulsion dynamics, which may contribute to chronic fecal retention and incontinence. Abnormalities of anorectal sensory and motor function and of rectosphincteric continence mechanisms do not seem to be important in the pathogenesis of childhood encopresis.

Computer analysis of radionuclide esophageal transit studies

For detailed examination of the esophageal transit of a swallowed radioactive liquid bolus, three computer-based techniques have been developed: (a) analysis of time-activity curves with decomposition into rapid and residual components, yielding the mean transit time for the former and the residual fraction for the latter; (b) reduction of dynamic image sequences to single condensed images, facilitating subjective assessment; and (c) tracking of the centroid of radioactivity, permitting quantification of retrograde motion. Studies were performed on 12 normal subjects and on six patients with motility disorders. Elevated residual fractions were observed in all the patients, and an abnormal degree of retrograde motion in two. Two normal and two abnormal studies exemplify the variety of patterns observed in condensed images.

A neonatal insert adaptor for a capnometer breathe-through cell

This paper describes a neonatal insert for use with the Hewlett-Packard Model 47210A capnometer airway adaptor. Dead space using this adaptor is 4.2 ml, which compares to 28.4 ml with the standard adaptor system and 4.0 ml with the pediatric Y-piece and endotracheal tube alone. Resistance was evaluated by plotting pressure drop-flow relationships. For oxygen flow rates used of up to seven L/min, the neonatal insert reduced the pressure drop as compared to both the standard adaptor and the pediatric Y-piece and endotracheal tube alone. Pressure drops were not very much larger than calculated theoretical values.

Anorectal sensorimotor dysfunction in fecal incontinence and diabetes mellitus. Modification with biofeedback therapy

We studied anorectal sensory and motor function in 14 diabetics with fecal incontinence and compared the results with those in 13 continent diabetics, 31 nondiabetics with fecal incontinence, and 11 continent nondiabetics. The threshold volume at which diabetic patients with fecal incontinence experienced rectal sensation was higher (25.0 +/- 3.4 ml [mean +/- S.E.M.]) than that in continent diabetics (13.0 +/- 2.4 ml) or nondiabetics with or without incontinence (14.5 +/- 1.5 and 12.5 +/- 1.8 ml, respectively; P less than 0.02). Biofeedback conditioning in 11 incontinent diabetics led to normal sensory thresholds in six of seven patients with pretreatment thresholds above 20 ml; five of these six became continent. Biofeedback also improved external-sphincter function in nine diabetics, eight of whom became continent. Overall, 8 of 11 diabetics had a reduction in fecal soiling after biofeedback therapy. We conclude that fecal incontinence in diabetics may be caused by decreased rectal sensation or impaired function of the external sphincter or both, and that these abnormalities can often be improved by biofeedback therapy with resultant reestablishment of bowel control.

Inappropriate use of cimetidine in hospitalized patients

We reviewed the records of 100 medical and surgical patients who received cimetidine while hospitalized. Cimetidine use was categorized by FDA criteria as justified (23%), acceptable (40%), or unjustified (37%); prescribing patterns were similar in medical and surgical patients. Furthermore, intravenous cimetidine was often given when patients were receiving oral feedings, which resulted in unnecessary increases in hospital costs.

Biofeedback for neurogenic fecal incontinence: rectal sensation is a determinant of outcome

Fifteen subjects (ages 5-33 years) with meningomyelocele and fecal incontinence underwent anorectal manometry followed by biofeedback conditioning of the external anal sphincter or nearby gluteal muscles. Seven of the 15 subjects undergoing biofeedback had improvement, defined as a 75% or greater decrease in the frequency of soiling, with a mean follow-up period of 23.1 months (range, 8-30 months). The seven subjects who improved with biofeedback had significantly lower thresholds of rectal sensation (smallest volume of distension perceived) than did the eight nonresponders; all responders had a sensory threshold less than or equal to 20 ml, whereas five of eight nonresponders had thresholds exceeding this level. Twenty-one children (ages 4-17 years) also underwent anorectal manometry, but not biofeedback conditioning, in order to evaluate the relationship of rectal sensation and peripheral neurological deficits. Fifteen of the 36 subjects with meningomyelocele had absent rectal sensation or thresholds exceeding 20 ml; there was no correlation of anorectal manometric parameters and peripheral sensorimotor levels. Response to biofeedback by children with meningomyelocele strongly correlates with rectal sensory thresholds which do not correlate with peripheral sensorimotor levels. If children with meningomyelocele and fecal incontinence are motivated and have adequate strength and coordination of the muscles of the lower extremities, anorectal manometry is the most accurate test to identify those who may benefit from biofeedback conditioning.