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Management of Low Anterior Resection Syndrome (LARS) Following Resection for Rectal Cancer. Cancers (Basel) 2023; 15:cancers15030778. [PMID: 36765736 PMCID: PMC9913853 DOI: 10.3390/cancers15030778] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/21/2023] [Accepted: 01/22/2023] [Indexed: 02/03/2023] Open
Abstract
INTRODUCTION A total of 60-80% of patients undergoing rectal resection (mostly as a treatment for rectal cancer) suffer from a variety of partly severe functional problems despite preservation of the anal sphincter. These patients are summarized under the term low anterior resection syndrome (LARS). Preoperative radiotherapy, vascular dissection and surgical excision of the low rectum and mesorectum lead, alone or all together, to a significant impairment of colonic and (neo-) rectal motility. This results in a variety of symptoms (multiple defecation episodes, recurrent episodes of urge, clustering, incontinence, etc.) which are associated with severe impairment of quality of life (QOL). METHODS This narrative review summarizes the present state of knowledge regarding the pathophysiology of LARS as well as the evidence for the available treatment options to control the symptoms resulting from this condition. RESULTS A review of the literature (Medline, Pubmed) reveals a variety of treatment options available to control symptoms of LARS. Medical therapy, with or without dietary modification, shows only a modest effect. Pelvic floor rehabilitation consisting of muscle exercise techniques as well as biofeedback training has been associated with improvement in LARS scores and incontinence, albeit with limited scientific evidence. Transanal irrigation (TAI) has gained interest as a treatment modality for patients with LARS due to an increasing number of promising data from recently published studies. Despite this promising observation, open questions about still-unclear issues of TAI remain under debate. Neuromodulation has been applied in LARS only in a few studies with small numbers of patients and partly conflicting results. CONCLUSION LARS is a frequent problem after sphincter-preserving rectal surgery and leads to a marked impairment of QOL. Due to the large number of patients suffering from this condition, mandatory identification, as well as treatment of affected patients, must be considered during surgical as well as oncological follow-up. The use of a standardized treatment algorithm will lead to sufficient control of symptoms and a high probability of a marked improvement in QOL.
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Lin AY, Varghese C, Paskaranandavadivel N, Seo S, Du P, Dinning P, Bissett IP, O'Grady G. Faecal incontinence is associated with an impaired rectosigmoid brake and improved by sacral neuromodulation. Colorectal Dis 2022; 24:1556-1566. [PMID: 35793162 PMCID: PMC10084032 DOI: 10.1111/codi.16249] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 05/04/2022] [Accepted: 05/20/2022] [Indexed: 01/07/2023]
Abstract
BACKGROUND The rectosigmoid brake, characterised by retrograde cyclic motor patterns on high-resolution colonic manometry, has been postulated as a contributor to the maintenance of bowel continence. Sacral neuromodulation (SNM) is an effective therapy for faecal incontinence, but its mechanism of action is unclear. This study aims to investigate the colonic motility patterns in the distal colon of patients with faecal incontinence, and how these are modulated by SNM. METHODS A high-resolution fibreoptic colonic manometry catheter, containing 36 sensors spaced at 1-cm intervals, was positioned in patients with faecal incontinence undergoing stage 1 SNM. One hour of pre- and post meal recordings were obtained followed by pre- and post meal recordings with suprasensory SNM. A 700-kcal meal was given. Data were analysed to identify propagating contractions. RESULTS Fifteen patients with faecal incontinence were analysed. Patients had an abnormal meal response (fewer retrograde propagating contractions compared to controls; p = 0.027) and failed to show a post meal increase in propagating contractions (mean 17 ± 6/h premeal vs. 22 ± 9/h post meal, p = 0.438). Compared to baseline, SNM significantly increased the number of retrograde propagating contractions in the distal colon (8 ± 3/h premeal vs. 14 ± 3/h premeal with SNM, p = 0.028). Consuming a meal did not further increase the number of propagating contractions beyond the baseline upregulating effect of SNM. CONCLUSION The rectosigmoid brake was suppressed in this cohort of patients with faecal incontinence. SNM may exert a therapeutic effect by modulating this rectosigmoid brake.
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Affiliation(s)
- Anthony Y Lin
- Department of Surgery, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Chris Varghese
- Department of Surgery, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | | | - Sean Seo
- Department of Surgery, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Peng Du
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Phil Dinning
- Department of Gastroenterology, Flinders Medical Centre, Bedford Park, South Australia, Australia.,Discipline of Human Physiology, Flinders University, Adelaide, South Australia, Australia
| | - Ian P Bissett
- Department of Surgery, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Greg O'Grady
- Department of Surgery, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand.,Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
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3
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Varghese C, Wells CI, Bissett IP, O'Grady G, Keane C. The role of colonic motility in low anterior resection syndrome. Front Oncol 2022; 12:975386. [PMID: 36185226 PMCID: PMC9523793 DOI: 10.3389/fonc.2022.975386] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Low anterior resection syndrome (LARS) describes the symptoms and experiences of bowel dysfunction experienced by patients after rectal cancer surgery. LARS is a complex and multifactorial syndrome exacerbated by factors such as low anastomotic height, defunctioning of the colon and neorectum, and radiotherapy. There has recently been growing awareness and understanding regarding the role of colonic motility as a contributing mechanism for LARS. It is well established that rectosigmoid motility serves an important role in coordinating rectal filling and maintaining continence. Resection of the rectosigmoid may therefore contribute to LARS through altered distal colonic and neorectal motility. This review evaluates the role of colonic motility within the broader pathophysiology of LARS and outlines future directions of research needed to enable targeted therapy for specific LARS phenotypes.
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Affiliation(s)
- Chris Varghese
- Department of Surgery, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Cameron I Wells
- Department of Surgery, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
- Department of General Surgery, Counties Manukau District Health Board, Auckland, New Zealand
| | - Ian P Bissett
- Department of Surgery, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
- Department of Surgery, Auckland City Hospital, Auckland, New Zealand
| | - Gregory O'Grady
- Department of Surgery, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Celia Keane
- Department of Surgery, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
- Department of Surgery, Whangārei Hospital, Whangarei, New Zealand
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4
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Bharucha AE, Knowles CH, Mack I, Malcolm A, Oblizajek N, Rao S, Scott SM, Shin A, Enck P. Faecal incontinence in adults. Nat Rev Dis Primers 2022; 8:53. [PMID: 35948559 DOI: 10.1038/s41572-022-00381-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/29/2022] [Indexed: 11/09/2022]
Abstract
Faecal incontinence, which is defined by the unintentional loss of solid or liquid stool, has a worldwide prevalence of ≤7% in community-dwelling adults and can markedly impair quality of life. Nonetheless, many patients might not volunteer the symptom owing to embarrassment. Bowel disturbances, particularly diarrhoea, anal sphincter trauma (obstetrical injury or previous surgery), rectal urgency and burden of chronic illness are the main risk factors for faecal incontinence; others include neurological disorders, inflammatory bowel disease and pelvic floor anatomical disturbances. Faecal incontinence is classified by its type (urge, passive or combined), aetiology (anorectal disturbance, bowel symptoms or both) and severity, which is derived from the frequency, volume, consistency and nature (urge or passive) of stool leakage. Guided by the clinical features, diagnostic tests and therapies are implemented stepwise. When simple measures (for example, bowel modifiers such as fibre supplements, laxatives and anti-diarrhoeal agents) fail, anorectal manometry and other tests (endoanal imaging, defecography, rectal compliance and sensation, and anal neurophysiological tests) are performed as necessary. Non-surgical options (diet and lifestyle modification, behavioural measures, including biofeedback therapy, pharmacotherapy for constipation or diarrhoea, and anal or vaginal barrier devices) are often effective, especially in patients with mild faecal incontinence. Thereafter, perianal bulking agents, sacral neuromodulation and other surgeries may be considered when necessary.
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Affiliation(s)
- Adil E Bharucha
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA.
| | - Charles H Knowles
- Blizard Institute, Centre for Neuroscience, Surgery & Trauma, Queen Mary University of London, London, UK
| | - Isabelle Mack
- University Hospital, Department of Psychosomatic Medicine, Tübingen, Germany
| | - Allison Malcolm
- Department of Gastroenterology, Royal North Shore Hospital and University of Sydney, Sydney, New South Wales, Australia
| | - Nicholas Oblizajek
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA
| | - Satish Rao
- Department of Gastroenterology, University of Georgia, Augusta, GA, USA
| | - S Mark Scott
- Blizard Institute, Centre for Neuroscience, Surgery & Trauma, Queen Mary University of London, London, UK
| | - Andrea Shin
- Division of Gastroenterology and Hepatology, Indiana University, Indianapolis, IN, USA
| | - Paul Enck
- University Hospital, Department of Psychosomatic Medicine, Tübingen, Germany.
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5
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The Sphincter of O'Beirne - Part 1: Study of 18 Normal Subjects. Dig Dis Sci 2021; 66:3516-3528. [PMID: 33462748 DOI: 10.1007/s10620-020-06657-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 10/05/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Gastroenterologists have ignored or emphasized the importance of the rectosigmoid junction in continence or constipation on and off for 200 years. Here, we revisit its significance using high-resolution colonic manometry. METHODS Manometry, using an 84-channel water-perfused catheter, was performed in 18 healthy volunteers. RESULTS The rectosigmoid junction registers as an intermittent pressure band of 26.2 ± 7.2 mmHg, or intermittent phasic transient pressure increases at a dominant frequency of 3 cpm and an amplitude of 28.6 ± 8.6 mmHg; or a combination of tone and transient pressures, at a single sensor, 10-17 cm above the anal verge. Features are its relaxation or contraction in concert with relaxation or contraction of the anal sphincters when a motor pattern such as a high-amplitude propagating pressure wave or a simultaneous pressure wave comes down, indicating that such pressure increases or decreases at the rectosigmoid junction are part of neurally driven programs. We show that the junction is a site where motor patterns end, or where they start; e.g. retrogradely propagating cyclic motor patterns emerge from the junction. CONCLUSIONS The rectosigmoid junction is a functional sphincter that should be referred to as the sphincter of O'Beirne; it is part of the "braking mechanism," contributing to continence by keeping content away from the rectum. In an accompanying case report, we show that its excessive presence in a patient with severe constipation can be a primary pathophysiology.
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6
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Chen JH, Collins SM, Milkova N, Pervez M, Nirmalathasan S, Tan W, Hanman A, Huizinga JD. The Sphincter of O'Beirne-Part 2: Report of a Case of Chronic Constipation with Autonomous Dyssynergia. Dig Dis Sci 2021; 66:3529-3541. [PMID: 33462747 DOI: 10.1007/s10620-020-06723-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 11/15/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Chronic constipation can have one or more of many etiologies, and a diagnosis based on symptoms is not sufficient as a basis for treatment, in particular surgery. AIM To investigate the cause of chronic constipation in a patient with complete absence of spontaneous bowel movements. METHODS High-resolution colonic manometry was performed to assess motor functions of the colon, rectum, the sphincter of O'Beirne and the anal sphincters. RESULTS Normal colonic motor patterns were observed, even at baseline, but a prominent high-pressure zone at the rectosigmoid junction, the sphincter of O'Beirne, was consistently present. In response to high-amplitude propagating pressure waves (HAPWs) that were not consciously perceived, the sphincter and the anal sphincters would not relax and paradoxically contract, identified as autonomous dyssynergia. Rectal bisacodyl evoked marked HAPW activity with complete relaxation of the sphincter of O'Beirne and the anal sphincters, indicating that all neural pathways to generate the coloanal reflex were intact but had low sensitivity to physiological stimuli. A retrograde propagating cyclic motor pattern initiated at the sphincter of O'Beirne, likely contributing to failure of content to move into the rectum. CONCLUSIONS Chronic constipation without the presence of spontaneous bowel movements can be associated with normal colonic motor patterns but a highly exaggerated pressure at the rectosigmoid junction: the sphincter of O'Beirne, and failure of this sphincter and the anal sphincters to relax associated with propulsive motor patterns. The sphincter of O'Beirne can be an important part of the pathophysiology of chronic constipation.
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Affiliation(s)
- Ji-Hong Chen
- Department of Medicine-Gastroenterology, Farncombe Family Digestive Health Research Institute, McMaster University, HSC-3H1F, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada.
| | - Stephen M Collins
- Department of Medicine-Gastroenterology, Farncombe Family Digestive Health Research Institute, McMaster University, HSC-3H1F, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Natalija Milkova
- Department of Medicine-Gastroenterology, Farncombe Family Digestive Health Research Institute, McMaster University, HSC-3H1F, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Maham Pervez
- Department of Medicine-Gastroenterology, Farncombe Family Digestive Health Research Institute, McMaster University, HSC-3H1F, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Sharjana Nirmalathasan
- Department of Medicine-Gastroenterology, Farncombe Family Digestive Health Research Institute, McMaster University, HSC-3H1F, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Wei Tan
- Department of Medicine-Gastroenterology, Farncombe Family Digestive Health Research Institute, McMaster University, HSC-3H1F, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Alicia Hanman
- Department of Medicine-Gastroenterology, Farncombe Family Digestive Health Research Institute, McMaster University, HSC-3H1F, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Jan D Huizinga
- Department of Medicine-Gastroenterology, Farncombe Family Digestive Health Research Institute, McMaster University, HSC-3H1F, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
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7
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Lin AY, Dinning PG, Milne T, Bissett IP, O'Grady G. The "rectosigmoid brake": Review of an emerging neuromodulation target for colorectal functional disorders. Clin Exp Pharmacol Physiol 2018; 44:719-728. [PMID: 28419527 DOI: 10.1111/1440-1681.12760] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 03/09/2017] [Accepted: 03/27/2017] [Indexed: 12/11/2022]
Abstract
The regulation of gastrointestinal motility encompasses several overlapping mechanisms including highly regulated and coordinated neurohormonal circuits. Various feedback mechanisms or "brakes" have been proposed. While duodenal, jejunal, and ileal brakes are well described, a putative distal colonic brake is less well defined. Despite the high prevalence of colonic motility disorders, there is little knowledge of colonic motility owing to difficulties with organ access and technical difficulties in recording detailed motor patterns along its entire length. The motility of the colon is not under voluntary control. A wide range of motor patterns is seen, with long intervals of intestinal quiescence between them. In addition, the use of traditional manometric catheters to record contractile activity of the colon has been limited by the low number of widely spaced sensors, which has resulted in the misinterpretation of colonic motor patterns. The recent advent of high-resolution (HR) manometry is revolutionising the understanding of gastrointestinal motor patterns. It has now been observed that the most common motor patterns in the colon are repetitive two to six cycles per minute (cpm) propagating events in the distal colon. These motor patterns are prominent soon after a meal, originate most frequently in the rectosigmoid region, and travel in the retrograde direction. The distal prominence and the origin of these motor patterns raise the possibility of them serving as a braking mechanism, or the "rectosigmoid brake," to limit rectal filling. This review aims to describe what is known about the "rectosigmoid brake," including its physiological and clinical significance and potential therapeutic applications.
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Affiliation(s)
- Anthony Y Lin
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Phil G Dinning
- Department of Gastroenterology and Surgery, Flinders Medical Centre, and the Discipline of Human Physiology, Flinders University, Bedford Park, South Australia, Australia
| | - Tony Milne
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Ian P Bissett
- Department of Surgery, University of Auckland, Auckland, New Zealand.,Department of Surgery, Auckland City Hospital, Auckland, New Zealand
| | - Gregory O'Grady
- Department of Surgery, University of Auckland, Auckland, New Zealand.,Department of Surgery, Auckland City Hospital, Auckland, New Zealand
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8
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Is it possible to give a single definition of the rectosigmoid junction? Surg Radiol Anat 2017; 40:431-438. [DOI: 10.1007/s00276-017-1954-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 12/04/2017] [Indexed: 01/16/2023]
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9
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Ikard RW. Spiral rectal valves: Anatomy, eponyms, and clinical significance. Clin Anat 2014; 28:436-41. [PMID: 25220837 DOI: 10.1002/ca.22462] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 08/20/2014] [Indexed: 11/07/2022]
Abstract
Rectal wall valves are obscure anatomic parts that rarely are considered in current medical practice. Yet from the seminal analysis of them in the early nineteenth century by the Irish anatomist and surgeon, John Houston, their structure, purpose, and clinical significance were topics of surprising disagreement. Were they true structures? What function might they have? Did disease originate in rectal valves? Were special operations required for any such diseases? Because Houston's anatomic analyses of rectal valves were substantiated, they came to be known in the English literature as the Spiral Rectal Valves of Houston. In the mid-nineteenth century, a single mid-rectal valve was described by the Hanoverian, Otto Kohlrausch., creating confusion with the established eponym "Houston's Valves." Many hypotheses about rectal valves have been discredited; and their physiologic functions are still unknown.
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Affiliation(s)
- Robert W Ikard
- Department of Surgery Vanderbilt University School of Medicine and Department of Surgical Services, VA Tennessee Valley Healthcare, 308 Sunnyside Drive, Nashville, Tennessee
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10
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Abstract
Human defecation involves integrated and coordinated sensorimotor functions, orchestrated by central, spinal, peripheral (somatic and visceral), and enteric neural activities, acting on a morphologically intact gastrointestinal tract (including the final common path, the pelvic floor, and anal sphincters). The multiple factors that ultimately result in defecation are best appreciated by describing four temporally and physiologically fairly distinct phases. This article details our current understanding of normal defecation, including recent advances, but importantly identifies those areas where knowledge or consensus is still lacking. Appreciation of normal physiology is central to directed treatment of constipation and also of fecal incontinence, which are prevalent in the general population and cause significant morbidity.
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Affiliation(s)
- Somnath Palit
- Academic Surgical Unit (GI Physiology Unit), Barts and the London School of Medicine and Dentistry, Blizard Institute, Queen Mary University, London, UK.
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11
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Scott SM, Picon L, Knowles CH, Fourquet F, Yazaki E, Williams NS, Lunniss PJ, Wingate DL. Automated quantitative analysis of nocturnal jejunal motor activity identifies abnormalities in individuals and subgroups of patients with slow transit constipation. Am J Gastroenterol 2003; 98:1123-34. [PMID: 12809838 DOI: 10.1111/j.1572-0241.2003.07419.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Small bowel dysmotility has previously been demonstrated in some patients with slow transit constipation (STC), suggesting a generalized intestinal disorder. However, no study has addressed whether the incidence of small intestinal dysfunction differs between subgroups of patients in this heterogeneous population. Using appropriate methodology, we aimed to determine prospectively the proportion of individuals with abnormal small bowel motility, and to assess whether heterogeneity in terms of pattern of colonic transit delay (based on (111)In diethylene-triamine-pentaacetic acid (DTPA) isotope scintigraphy), or mode of onset (based on clinical history) is of importance. METHODS Thirty-seven patients with STC underwent 24-h ambulatory jejunal manometry; data were compared with those obtained in 38 healthy controls. Automated quantitative analysis of seven variables of the nocturnal migrating motor complex was performed, to assess whether differences existed between groups, and whether individual patients had evidence of small intestinal dysmotility, defined as two or more measures of migrating motor complex variables outside the normal range. Four variables differed significantly between STC patients and controls: in phase III, propagation was slower, duration was longer, and contraction amplitude was higher; in phase II, contraction frequency was increased. Seven of 24 patients with a generalized pattern of colonic transit delay had abnormal small bowel motility compared with none of 13 with a left-sided delay (p < 0.04). These included four patients with chronic idiopathic symptoms and three with acquired symptoms. Approximately one third of patients with a generalized delay in colonic transit had evidence of jejunal enteric neuromuscular dysfunction. Individual patients with a left-sided colonic delay did not satisfy the criteria for nocturnal small bowel dysmotility, but as a group, some differences were noted from controls. In contrast to previous reports, evidence of generalized enteric dysmotility may be present irrespective of the mode of onset.
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Affiliation(s)
- S M Scott
- Gastrointestinal Physiology Unit, Academic Department of Surgery, Queen Mary's School of Medicine and Dentistry, London, United Kingdom
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12
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Shafik A, Mostafa RM, Shafik AA. Electrophysiological study of the rectosigmoid canal: evidence of a rectosigmoid sphincter. J Anat 2002; 200:517-21. [PMID: 12090397 PMCID: PMC1570712 DOI: 10.1046/j.1469-7580.2002.00049.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2002] [Indexed: 11/20/2022] Open
Abstract
Previous studies strongly suggest the presence of a sphincter at the rectosigmoid junction, an area with a mean length of 2.8 cm in adults, called the rectosigmoid canal (RSC). To find supporting evidence of a sphincteric function for the RSC, two recording electrodes were applied to each of the sigmoid colon (SC), RSC and rectum (R) in 11 subjects during operative repair of huge incisional hernias. The RSC, SC and R were individually stimulated by a further electrode and their pressures monitored by a three-channel microtip catheter. The variables of the slow waves or pacesetter potentials, recorded at rest from the RSC and R, were significantly higher than those of the SC. While the frequency and conduction velocity of pacesetter potentials of the RSC and R were similar, the potential pacesetter amplitude of the RSC was significantly higher. The increase of the electrical activity and pressure upon electrostimulation was significantly greater in the RSC than that of the SC or R. Electrostimulation led to an increase in pressure of all three areas, the RSC increase being significantly the greatest. The greater increase of the electrical activity and pressure of the rectosigmoid canal upon electrostimulation, compared to that of the SC or R, strongly supports the presence of a rectosigmoid sphincter.
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Affiliation(s)
- Ahmed Shafik
- Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt.
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13
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Wadhwa RP, Mistry FP, Bhatia SJ, Abraham P. Existence of a high pressure zone at the rectosigmoid junction in normal Indian men. Dis Colon Rectum 1996; 39:1122-5. [PMID: 8831527 DOI: 10.1007/bf02081412] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
PURPOSE A hypertonic, electrically hyperactive segment has been described in the rectosigmoid region mainly in constipated persons. Anatomic or manometric evidence to satisfy the criteria for a sphincter here is, however, inconclusive. We evaluated the pressure profile of the rectosigmoid region in normal Indian men. METHODS Fifteen male volunteers with regular bowel habits were studied. Rectosigmoid manometry (1 cm station pull-through) was done in the fasting state using a water-perfused system and three-lumen catheter with radially oriented recording ports 5 cm apart. RESULTS Eight volunteers had a zone of high pressure. Proximal extent of this zone was identified as the station with a rise in basal pressure of at least 10 mmHg over the previous station. A further rise of at least 10 mmHg in subsequent distal stations was considered essential for defining the existence of the zone. This zone had a median length of 3 cm, with midpoint at median 18 cm from the anal verge and median highest pressure of 36 mmHg. There was no antegrade pressure gradient across the zone; rectal pressures were higher than those in the sigmoid in 12 of 15 volunteers. CONCLUSIONS Approximately one-half of normal Indian men with regular bowel habits have a high pressure zone in the rectosigmoid region. The role of diet or defecation posture in its etiology and its effect on bowel habit need to be studied.
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Affiliation(s)
- R P Wadhwa
- Department of Gastroenterology, King Edward Memorial Hospital, Bombay, India
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14
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Longo WE, Ballantyne GH, Modlin IM. The colon, anorectum, and spinal cord patient. A review of the functional alterations of the denervated hindgut. Dis Colon Rectum 1989; 32:261-7. [PMID: 2646085 DOI: 10.1007/bf02554543] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
As humans have become more mechanized, the number of persons sustaining spinal cord injuries resulting in quadriplegia or paraplegia has increased. Because colorectal function is modulated by a combination of neural, hormonal, and luminal influences, many of the normal regulatory mechanisms remain intact in patients with spinal cord injuries. Management of these patients, however, requires an understanding of altered function in the denervated hindgut. The foregut and midgut are innervated by parasympathetic fibers in the vagus and sympathetic fibers from the lower six thoracic vertebra. In contrast, the hindgut is innervated by parasympathetic fibers arising from the sacral plexus and sympathetic fibers from the lumbar spinal column. Consequently, in most spinal cord injuries, the foregut and midgut remain normally innervated whereas the hindgut looses input from cerebral and spinal cord sources. In high cord lesions this results in decreased colonic motility. In low cord injuries there is loss of inhibitory influences that normally down-regulate left colonic and rectosigmoid sphincter activity. This increased motility causes a loss of left colonic compliance and increases left colonic transit, thus leading to chronic constipation. At the same time in both high and low cord injuries, reflex activity of the anorectum is left unregulated by cerebral input. Once stimulated by distention, the rectum spontaneously evacuates its contents. Thus, fecal impaction and incontinence in these patients principally results from loss of inhibitory influences on rectosigmoid sphincter activity and on rectal reflex activity.
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Affiliation(s)
- W E Longo
- Gastrointestinal Surgery Research Unit, Yale University School of Medicine, West Haven, Connecticut
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