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Biomedical subjects

P Arhan

Publications and source records attributed to P Arhan.

At least 55 records · Page 3Linked to original sources

[Sigmoid motility stimulated by luminal distention. Changes in the motility response in constipation by the slowing down of left colonic transit].

The aim of our study was to develop a new technique of sigmoid manometry using standardized luminal distensions and to compare patterns of colonic motility following distension in normal subjects and in constipated patients. Eight subjects without colonic disturbances and 8 constipated patients with delayed transit time of the left colon as shown by radiopaque markers were investigated. Sigmoid motor activity was recorded by measuring pressure in a distending latex balloon placed at 25 cm from the anus. Inflations were maintained during 250 s and separated by 60 s recovery periods of deflation. Volumes of air (V) were increased until the patient reported abdominal pain (VMT). For each distension level, the resistance to distension of the bowel wall evaluated by the baseline adaptative pressure (P) and the contractile activity (A) quantified by planimetry of the active contractile activity (A) quantified by planimetry of the active contraction waves superimposed to P were assessed. In normal subjects, VMT was 147 +/- 9 ml. P increased linearly with V (p less than 0.03) up to 4,336 +/- 876 Pa. A increased with V until VMT/2 reached the maximum of 389 +/- 72 Pa*; for higher volumes A decreased significantly with to 166 +/- 46 Pa for VMT. Reference to controls, the constipated patients had a decreased VMT (61 +/- 4 ml). P increase at VMT (5,084 +/- 753 Pa) and A maximal value (387 +/- 176 Pa) were not different.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Megarectum.

Evaluation of the rectum by barium enema does not correlate well with rectometrographic studies and is not predictive of bowel function. The purpose of the present study was to describe clinical and functional data in patients with chronic idiopathic constipation, where a megarectum was diagnosed by a rectometrogram. Among 355 patients who underwent rectal elasticity studies, 35 were found to have a megarectum (maximum tolerable volume above 320 ml in women and 440 in men) for which no specific etiology was recognized. They, and a group of 11 healthy controls who were not sensitive to stress, underwent studies of stool frequency, colonic transit time of radiopaque markers, rectal elasticity, and anorectal pressures and reflexes. The elasticity coefficient of the rectal wall was decreased in patients as compared to controls (P less than 0.01). Seven patients had onset of symptoms at birth, with maximum tolerable volume in the rectum between 460 and 900 ml, and all were incontinent for feces. Studies of colonic transit times demonstrated normal function in the right and left colon, but there was rectosigmoid stagnation (transit time of 122 +/- 17 hr vs 8 +/- 2 in stress-free controls; X +/- SE; P less than 0.001). In the other 28 patients (late-onset megarectum), in contrast to the congenital group, there was a marked female preponderance, and their recorded stool frequency (4 +/- 0.7/week) was greater than the recalled frequency (1.4 +/- 0.2/week; P less than 0.001). Only half suffered from fecal incontinence. They did not have a greater rectal capacity when colonic transit times were prolonged (455 +/- 27 ml) than when normal (422 +/- 27). Rectal pressure was similar at the level of conscious sensation of filling, regardless of rectal capacity, suggesting a motor, rather than a sensory, abnormality. The amplitude of the rectoanal inhibitory reflex was decreased (P less than 0.001) as compared to controls, sometimes mimicking the findings of Hirschsprung's disease, but increasing rectal distension always induced a relaxation of the internal anal sphincter. The notion of a megarectum, which tolerates large amounts of fluid without sensation, lacks elasticity, and is accompanied by an abnormal rectoanal inhibitory reflex, provides an explanation for one of the mechanisms of constipation by outlet obstruction.

Adult↗

Relationship between parietal blood flow studies in the left colon and the rectum in dogs. Colonic pressure and blood flow.

An animal model was proposed to clarify the difference in occurrence of enterocolitis in congenital aganglionosis. When gaseous distention of the colon was localized to the rectosigmoid area, enterocolitis never occurred. On the contrary, when it involved the left colon, enterocolitis occurred in 13 of 15 patients. Intestinal blood flow rates were simultaneously measured in the left colon and rectum of six dogs by using labeled microspheres and expressed in function of the intraluminal pressure. Results show that for elevated values of intraluminal pressure, blood flow was significantly lower in the left colon than in the rectum. These results may explain why ischemia and necrosis occurred more frequently in the left colon than in the rectum.

Animals↗

[Action of trimethyl 3,3-N-hexene-5-lactam on the mechanical properties of the longitudinal fibers of the rat colon. An in vitro study].

The effects of trimethyl 3,3-N-hexene-5-lactam (T. H. L.) on the mechanical properties of longitudinal muscle strips of the distal rat colon were investigated through stretching, electrical stimulation and addition of pharmacologic agents. T. H. L. abolished the contraction induced by electrical stimulation and decreased amplitude of contractions induced by carbamoylcholine and serotonin. It further reduced the relaxation induced by adrenaline.

Animals↗

[Propagation of the gastric peristalsis in normal subjects and duodenal ulcer patients].

The velocities of gastric peristaltic waves were measured on fluorographic series made in normal subjects and patients with duodenal ulcer. After an overnight fast, the subjects drank 250 ml of barium suspension. Sequential radiograms were taken every 2 s during 30 s after two pyloric ejections. Peristaltic waves were located and their displacements measured with an Apple Graphic Tablet. Wave progression diagrams and velocity histograms were drawn for each subject. The velocities were calculated every 2 s. A "spread index" Ip was determined for each subject, characterizing the irregularity of propagation. Mean frequency and mean velocity were greater in duodenal ulcer patients (3.6 c/min; 3.7 mm/s) than in normal subjects (2.9 c/min; 2.4 mm/s; p less than 0.001). Nevertheless, no significant difference was found between proximal or midcorpus and antral velocities, in ulcer patients as well as in normal subjects, contrarily to classical data. However, the velocities were not uniform along the stomach. The contractions spread unevenly and displayed transient slopes. The irregularities of propagation were more pronounced in normal subjects, ranging from 0 to 14 mm/s with 28 p. 100 of velocities less than 1 mm/s, then in ulcer patients (0 to 13 mm/s with 12 p. 100 of low velocities). The spread index Ip was greater in normal (ranged from 0.54 to 2.62) than in ulcer patients (ranged from 0.16 to 0.48; p less than 0.001). This study showed that the propagation velocity of the peristaltic waves and its regularity were different in normal subjects and in duodenal ulcer patients.

Adult↗

Hindgut dysgenesis as a cause of constipation with delayed colonic transit.

In a patient complaining of constipation since birth, delayed transit time in the ascending colon was related to a congenital malformation of the hindgut, different from Hirschsprung's disease. This was associated with absence of the left lobe of the liver. There was no propagating electrical muscular activity in the distal bowel.

Adult↗

Measuring the anorectal angle.

Lateral radiographs of the rectum and anus were taken in 90 children with chronic idiopathic constipation. A computer program was developed to obtain an objective quantitative assessment of the anorectal angle; it averaged 120 degrees at rest, decreased during forceful anal contraction and increased during defecation. It was noted that 24% of the children, when asked to defecate, decreased their anorectal angle as normally observed during forceful anal contraction and, that 21% when asked to contract the anus, increased the angle as if they were defecating. This 'sphincteric disobedience' is probably of major clinical relevance to an understanding of the symptoms of these patients.

Adolescent↗

Comparative esophageal and anorectal motility in scleroderma.

Esophageal and anorectal pressures were recorded in 26 patients (4 men and 22 women) with scleroderma. Eleven patients suffered from a localized form of the disease and 15 from progressive systemic sclerosis. The latter only had marked functional abnormalities in esophageal and anorectal motility. Mean resting pressure at the lower esophageal sphincter of patients with progressive system sclerosis and controls was, respectively, 6 +/- 2 and 25 +/- 1 mmHg (p less than 0.001); mean closing pressure was 5 +/- 5 and 48 +/- 3 mmHg (p less than 0.001); coordination of opening the lower esophageal sphincter with the oncoming contraction in the distal esophagus was 0% and 68% +/- 5% (p less than 0.001); and relaxation (fall of the lower esophageal sphincter pressure to resting levels in the stomach) was 18% +/- 12% and 98% +/- 1% (p less than 0.001). The rectoanal inhibitory reflex was of lesser amplitude than normal in 74% of patients with progressive system sclerosis and was absent in 13%. Quantitative analysis demonstrated a significant reduction in response to rectal distention with 20 or more ml of air (p less than 0.001). There was a correlation between the amplitude of the lower esophageal sphincter relaxation and the amplitude of the rectoanal inhibitory reflex in response to rectal distention with 30-50 ml of air (p less than 0.05 to p less than 0.025). Our data show that in systemic sclerosis, anorectal motility is as frequently abnormal as esophageal motility.

Adult↗

[Idiopathic myositis of the small intestine. An unusual cause of chronic intestinal pseudo-obstruction in children].

The case reported concerns a child with chronic intestinal pseudo-obstruction (CIPO) whose digestive manifestations (intestinal adynamia and distension) were present from the age of 6 months and lasted, despite medical and surgical treatments until 4 years of age, when death occurred. The multiple samplings showed important inflammatory reactions centred on the muscular layers of the small intestine, together with degenerative lesions of the muscular fibres, progressively leading to fibrosis and atrophy of the intestinal wall with secondary and final impairment of the myenteric plexuses. The diagnosis of myositis of the small intestine is extremely rare. It is not part of the usual causes of intestinal adynamia and CIPO, which were reviewed. Hollow visceral myopathy and systemic sclerosis of the GI tract were more especially discussed. For lack of etiopathogenic convincing data and of similar observation in the literature, this case may be temporarily considered as an idiopathic myositis of the small intestine, a potentially new cause of CIPO.

Appendix↗

Anorectal motility after surgery for spina bifida.

Anorectal motility was studied in 93 children (aged 15 days to 16 1/2 years) who had undergone surgery for myelocele or meningomyelocele, and 80 controls, matched for age and sex. Mean resting pressure in the anal canal of patients was markedly decreased, particularly in the presence of incontinence, and unstable. The recording of a rectoanal inhibitory reflex both in the upper anal canal and at the anal margin was associated with the presence of fecal incontinence and motor disorders of the lower extremities. Patients could be divided into four groups according to manometric pattern: 1) those with normal recordings (incontinence in 63 per cent), 2) those with spontaneous intermittent relaxations of the upper anal canal and simultaneous rectal contractions (incontinence in 91 per cent), 3) those with normal manometry except for unstable upper anal canal pressure (incontinence in 92 per cent), and 4) those with absence of the rectoanal inhibitory reflex and hypotonic anal canal (patients too young to appraise continence, all under 2 years).

Anal Canal↗

Functional abnormalities of the anal sphincters in patients with myotonic dystrophy.

Motility of the anorectal area was studied in 19 patients with myotonic dystrophy and in 20 control subjects, before and after pudendal block. In patients with myotonic dystrophy, before anesthesia, resting pressure in the upper anal canal ( p less than 0.001) and duration and amplitude of relaxation of the rectoanal inhibitory reflex (p less than 0.01) were decreased. A myotonic contraction of high amplitude followed relaxation in all patients, but in control subjects this was not the case. In the lower anal canal, the duration of the rectoanal contractile reflex was prolonged as compared with control subjects (p less than 0.001). The pudendal block had no effect in the upper anal canal either on resting pressure or on amplitude and duration of the rectoanal inhibitory reflex, neither in patients nor in controls. After blockade, however, the myotonic contraction subsequent to the reflex in patients was significantly reduced in amplitude (p less than 0.01). In lower anal canal, the resting pressure was reduced to similar levels, both in patients and in control subjects, after pudendal block (p less than 0.01), and the rectoanal contractile reflex was abolished in both groups. This study demonstrates a number of functional abnormalities in the anorectal structures of patients with myotonic dystrophy. These abnormalities produce a decrease in resting pressure in the anal canal, and a reflex myotonic contraction subsequent to rectal distention due to both external and internal sphincter dysfunction.

Adolescent↗

Constipation with colonic inertia. A manifestation of systemic disease?

Transit of radiopaque markers was delayed in the ascending colon of 51 females and 3 males treated for severe idiopathic constipation. Onset of symptoms was between age 10 and 20 in more than half of the patients. Eighteen percent had previously undergone unnecessary laparotomy for large bowel pseudoobstruction. Stool frequency ranged from 1 stool every three days to 1 every 2 months. Twenty-six percent suffered from fecal incontinence. In addition, 30% had orthostatic hypotension and 15% galactorrhea of idiopathic origin. Patients had a higher than normal anal pressure (P less than 0.001). They all had a rectoanal inhibitory reflex, but it was abnormal in 76%. In the upper esophageal sphincter, resting pressure was higher (P less than 0.02), and coordination poorer (P less than 0.05) than in normal control subjects. Incidence of spontaneous tertiary contractions in the body of the esophagus was greater than normal (P less than 0.03). In the lower esophageal sphincter, resting pressure was lower (P = 0.001) and gastroesophageal gradient weaker (P = 0.05). Closing pressure of the sphincter was lower (P less than 0.001) and coordination less adequate (P less than 0.02). After subcutaneous injection of 0.035 mg/kg bethanechol, urinary bladder intraluminal pressure increased by over 15 cm H2O in 31% of patients but never did in controls, and average maximal pressure was greater (P less than 0.025). Time taken to reach peak pressure was shorter (P less than 0.01). This study provides evidence that patients who suffer from constipation with colonic inertia also have abnormal function in other hollow viscera.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Idiopathic disorders of fecal continence in children.

A group of 176 patients aged 2 to 15 years was investigated for idiopathic disorders of bowel function other than Hirschsprung's disease. Anorectal motility, as well as colorectal transit of radiopaque markers, were investigated. Before the end of the first month of life, 70 of the patients were constipated. Resting pressure was more unstable (P less than 0.001) and higher than normal in the rectal ampulla and upper anal canal (P less than 0.01). Retardation of markers occurred in the proximal and/or distal large bowel of 61% of the patients. The existence of functional abnormalities was demonstrated in the majority of children with idiopathic disorders of fecal continence.

Adolescent↗

Ischemic fecal incontinence and rectal angina.

In 36 patients who consulted for fecal incontinence or rectal pain, or both, there was grossly visible scarring of the rectum and biopsy revealed mucosal atrophy and fibrosis. A steal from the hemorrhoidal arteries to the iliac vessels was demonstrated in 3 subjects. Maximum tolerable volumes within a rectal balloon were smaller than in control subjects, both in men (192 vs. 273 ml) and in women (142 vs. 217 ml) (p less than 0.01). The rectoanal inhibitory reflex was abnormal in all but 1 patient. Specific abnormalities were a decreased amplitude or a prolonged duration of the reflex. It was totally absent in 2 patients. This study is compatible with the hypothesis that chronic ischemia of the rectum may cause fecal incontinence or rectal pain.

Adult↗

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.

Adolescent↗

Urorectodynamics in patients with colonic inertia.

Sixteen female patients with colonic inertia and 12 control women underwent manometric evaluation of their bladder and rectal cavities. After subcutaneous injection of 0.035 mg./Kg. bethanechol, bladder intraluminal pressure increased by over 15 cm. water in 5 patients (31 per cent) and in none of the control group; maximal pressure after injection was 11.5 +/- 1.6 cm. H2O (mean +/- SE) in patients and 8.5 +/- 1 in controls (p less than 0.025). The intraluminal rectal pressure reached 23 +/- 4 cm. H2O in patients and only 11.9 +/- 1.4 in controls (p less than 0.0025). Time taken to reach a peak pressure was faster in patients both in bladder (17.4 +/- 0.7 vs. 19.8 +/- 1.2 minutes; p less than 0.01) and in the rectum 914.6 +/- 0.8 vs. 16.3 +/- 1.2; p less than 0.025). These findings and the clinical presentation suggest an autonomic neuropathic lesion in this group of patients.

Adult↗