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181.
j. desipio f. k. friedenberg a. korimilli j. e. richter h. p. parkman & r. s. fisher 《Neurogastroenterology and motility》2007,19(3):188-195
Manometric recording from the pyloric channel is challenging and is usually performed with a sleeve device. Recently, a solid-state manometry system was developed, which incorporates 36 circumferential pressure sensors spaced at 1-cm intervals. Our aim was to use this system to determine whether it provided useful manometric measurements of the pyloric region. We recruited 10 healthy subjects (7 males:3 females). The catheter (ManoScan(360)) was introduced transnasally and, in the final position, 15-20 sensors were in the stomach and the remainder distributed across the pylorus and duodenum. Patients were recorded fasting and then given a meal and recorded postprandially. Using pressure data and isocontour plots, the pylorus was identified in all subjects. Mean pyloric width was 2.1 +/- 0.1 cm (95% CI: 1.40-2.40). Basal pyloric pressure during phase I was 9.4 +/- 1.1 mmHg, while basal antral pressure was significantly lower (P = 0.003; 95% CI: 2.4-8.4). Pyloric pressure was always elevated relative to antral pressure in phase I. For phases II and III, pyloric pressure was 7.7 +/- 2.3 mmHg and 9.4 +/- 1.1 mmHg, respectively. Pyloric pressure increased similarly after both the liquid and solid meal. In addition, isolated pressure events and waves, which involve the pylorus, were readily identified. 相似文献
182.
183.
Abstract Available evidence implicates abnormal colonic contractility in patients suffering from constipation. Traditional analysis of colonic manometry focuses on the frequency, extent and amplitude of propagating sequences (PS). We tested the hypotheses that the spatio-temporal linkage among sequential PSs exists throughout the healthy human colon and is disrupted during constipation. In eight patients with severe constipation and eight healthy volunteers, we recorded colonic pressures from 16 regions (caecum–rectum) for 24 h. Sequential PSs were regionally linked if the two PSs originated from different colonic regions but the segments of colon traversed by each PS overlapped. In order to determine whether this linkage occurred by chance, a computer program was used to randomly rearrange all PSs in time. Data were re-analysed to compare regional linkage between randomly re-ordered PSs (expected) and the natural distribution of PSs (observed). In controls the observed regional linkage (82.5 ± 9.0%) was significantly greater than the expected value (60.5 ± 4.3%; P = 0.0001). In patients the observed and expected regional linkage did not differ. The (observed − expected) delta value of regional linkage in controls was significantly greater than in patients (21.7 ± 8.5% vs −2.3 ± 7.0%; P = 0.01). Regional linkage among sequential PSs in the healthy colon appears to be a real phenomenon and this linkage is lost in patients with constipation. Regional linkage may be important for normal colonic transit and loss of linkage might have pathophysiological relevance to and provide a useful biomarker of severe constipation. 相似文献
184.
Annette Mosbæk Nordenbo M.D. 《Sexuality and disability》1996,14(1):33-39
Bowel symptoms are seen in two thirds of multiple sclerosis (MS) patients, constipation and fecal incontinence, frequently
coexisting, being the major symptoms. Since bowel symptoms are common in community, the need for precise definitions of pathology
are stressed. Pathophysiological studies of bowel function are reviewed and the following hypothesis is suggested: Constipation
is caused by a delay in colonic transit time, by a delay in the defecation reflex and by early external sphincter exitation.
Fecal urgency/incontinence may be explained by impaired rectal sensation, not warning the patient to seek the toilet in time.
Decrease in rectal compliance and in some patients abnormal rectal contractions may facilitate fecal expulsion and weak external
sphincters allow leakage. Treatment options are commented and the need for treatment studies stressed. 相似文献
185.
To examine whether or not intraluminal pressure changes at a site in the human colon reflect with fidelity the local bowel wall contractions or relaxation, endoscopic recording of the changes in colonic calibre as a parameter of the motor events with simultaneous manometry was performed at a fixed site in a prepared sigmoid colon during the interdigestive state. In four of the 12 subjects, a total of 20 phasic pressure waves with an amplitude of 13–22 mmHg and a duration of 13–18 sec were obtained in a 20 min recording session. Eighteen of the 20 phasic pressure waves (90%) were associated not with a decrease (contraction) but with an increase in the calibre (relaxation). The pressure change began 0.2–8.4 sec (mean: 4.5 sec) behind and ended ? 1.8 to 8 sec (mean: 3.5 sec) ahead of the calibre change. In the other eight subjects, no phasic pressure change was recorded in the presence of an overt calibre change. We conclude that manometric phasic pressure change recorded at a site in the empty human colon is not necessarily correlated with the localized contractile activity. Extrapolation of pressure profiles in the colon to motor events at the manometric site should be cautious. 相似文献
186.
The role of the vagus nerve in the control of the intestinal migrating motor complex (MMC) is unclear. This study aimed to evaluate the effect of physiological vagal stimulation with sham feeding on phase III of the MMC. Antroduodenal motility was recorded in six healthy volunteers. The first phase III was used as a control, and sham feeding was performed during the second phase III. The MMC was disrupted within 1.5 ± 0.4 min of sham feeding and its duration was shorter than the control phase III. Phase III propagation was inhibited in all subjects, most of them exhibiting no propagation beyond the third duodenal recording site. During sham feeding, the antrum exhibited transient phasic contractions in five out of six subjects. The duodenal motility index recorded for up to 30 min after the onset of the sham feeding was unchanged in five out of six subjects. We conclude that sham feeding consistently interrupted phase III of the duodenal MMC and induced antral contractions, but failed to provoke significant motor events in the duodenum. 相似文献
187.
G. LUX I. VAN ELS G. S. THE T. BOZKURT K. H. ORTH D. BEHRENBECK 《Neurogastroenterology and motility》1995,7(1):20-30
Abstract The present study was performed to compare pain-related oesophageal motility, gastro-oesophageal reflux and ST-segment deviations in patients with intermittent chest pain and normal or pathological coronary angiography. Thirty patients (11 males, 19 females; mean age 54.8 years) with normal and 15 patients (12 males, 3 females; mean age 66.7 years) with pathological coronary angiography were investigated by 24-h oesophageal pressure, pH and ECG recording. Chest pain correlated with motility abnormalities or gastro-oesophageal reflux occurred in 33% (10/30) of patients with normal coronary arteries and in 26% of patients with pathological coronary angiography. Symptomatic and asymptomatic ST-segment changes were less frequently observed in patients with normal angiography (4/30) than in patients with pathological coronary angiography (7/14; P = 0.02). Oesophageal dysfunction coincided with ST-segment deviation in 6.7% (2/30) of patients with normal and 40% (6/15) of patients with pathological coronary angiography (P = 0.02). The conclusions reached were: (1) pain-correlated abnormal motility or gastro-oesophageal reflux occurred in patients with normal and pathological coronary angiography at the same frequency; (2) ambulatory motility and pH recording alone does not appear to differentiate between cardiac and non-cardiac chest pain; (3) simultaneous ECG recording reveals a significant correlation of ST-segment deviation and gastro-oesophageal reflux or abnormal motility in patients with coronary artery stenosis. 相似文献
188.
189.
s. k. ghosh p. janiak † m. fox † w. schwizer † g. s. hebbard ‡ & j. g. brasseur 《Neurogastroenterology and motility》2008,20(7):750-759
Abstract Distinct contraction waves (CWs) exist above and below the transition zone (TZ) between the striated and smooth muscle oesophagus. We hypothesize that bolus transport is impaired in patients with abnormal spatio-temporal coordination and/or contractile pressure in the TZ. Concurrent high resolution manometry and digital fluoroscopy were performed in healthy subjects and patients with reflux oesophagitis; a condition associated with ineffective oesophageal contractility and clearance. A detailed analysis of space–time variations in bolus movement, intra-bolus and intra-luminal pressure was performed on 17 normal studies and nine studies in oesophagitis patients with impaired bolus transit using an interactive computer based system. Compared with normal controls, oesophagitis patients had greater spatial separation between the upper and lower CW tails [median 5.2 cm (range 4.4–5.6) vs 3.1 cm (2.2–3.7)], the average relative pressure within the TZ region (TZ strength) was lower [30.8 mmHg (28.3–36.5) vs 45.8 mmHg (36.1–55.7), P < 0.001], and the risk of bolus retention was higher (90% vs 12%; P < 0.01). The presence of bolus retention was associated with a wider spatial separation of the upper and lower CWs (>3 cm, the upper limit of normal; P < 0.002), independent of the presence of oesophagitis. We conclude that bolus retention in the TZ is associated with excessively wide spatial separation between the upper and lower CWs and lower TZ muscle squeeze. These findings provide a physio-mechanical basis for the occurrence of bolus retention at the level of the aortic arch, and may underlie impaired clearance with reflux oesophagitis. 相似文献
190.
S. K. Ghosh J. E. Pandolfino M. A. Kwiatek P. J. Kahrilas 《Neurogastroenterology and motility》2008,20(12):1283-1290
Abstract This study analysed the association between oesophageal transition zone (TZ) defects [characterized by a delay and/or spatial gap between the terminus of the proximal oesophageal (striated muscle) contraction and the initiation of the distal oesophageal (smooth muscle) contraction] and dysphagia in a large patient cohort. Four hundred consecutive patients (178 with dysphagia) and 75 controls were studied with 36‐channel high‐resolution manometry (HRM). The resultant pressure topography plots were first analysed for impaired oesophagogastric junction (OGJ) relaxation, distal segment contractile abnormalities, and proximal contractile abnormalities using normal values from the 75 controls. If these aspects of oesophageal motility were deemed normal, the TZ was characterized by length and duration between the proximal and distal contractions using a 20 mmHg isobaric contour to establish the segment boundaries. Patients were then classified according to whether or not they exhibited TZ defects (spatial separation or delay) and the occurrence of unexplained dysphagia. Of the 400 patients, 267 were suitable for TZ analysis and of these 55 had a spatial or temporal TZ measurement exceeding the 95th percentile of the controls (2 cm, 1 s). Exactly 34.6% of the patients (n = 19) with spatial and/or temporal TZ defects had unexplained dysphagia, which was significantly more than seen with normal TZ dimensions (19.8%). Although far less common than distal peristaltic or OGJ abnormailites, TZ defects may be related to dysphagia in a minority of patients (<4% in this series) and should be considered a distinct oesophageal motility disorder. 相似文献