Motor Function Of The Pharynx Esophagus And Its Sphincters

Deglutition or a swallow begins as a voluntary act in the oral cavity but proceeds autonomously in the pharynx and esophagus. Bilateral sequenced activation and inhibition of more than 25 pairs of muscles of mouth, pharynx, larynx, and esophagus is required during a swallow. A single swallow elicits peristalsis in the pharynx and esophagus along with relaxation of upper and lower esophageal sphincters. Multiple swallows, at closely spaced time intervals, demonstrate deglutitive inhibition; sphincters remain relaxed during the entire period, but only the last swallow elicits peristalsis. Laryngeal inlet closure or airway protection is very important during swallow. Upper part of the esophagus that includes upper esophageal sphincter is composed of skeletal muscles, middle esophagus is composed of a mixture of skeletal and smooth muscles, and lower esophagus, including lower esophageal sphincter, is composed of smooth muscles. Peristalsis progresses in seamless fashion, despite separate control mechanism, from the skeletal to smooth muscle esophagus. The esophagus's circular and longitudinal muscle layers contract synchronously during peristalsis. Sphincters maintain continuous tone; neuromuscular mechanisms for tonic closure in the upper and lower esophageal sphincters are different. Lower esophageal sphincter transient relaxation, belching mechanism, regurgitation, vomiting, and reflux are mediated via the brain stem. Table of Contents: Introduction / Central Program Generator and Brain Stem / Pharynx-Anatomy, Neural Innervation, and Motor Pattern / Upper Esophageal Sphincter / Neuromuscular Anatomy of Esophagus and Lower Esophageal Sphincter / Extrinsic Innervation: Parasympathetic and Sympathetic / Interstitial Cells of Cajal / Recording Techniques / Motor Patterns of the Esophagus-Aboral and Oral Transport / Deglutitive Inhibition and Muscle Refractoriness / Peristalsis in the Circular and Longitudinal Muscles of the Esophagus / Neural and Myogenic Mechanism of Peristalsis / Central Mechanism of Peristalsis-Cortical and Brain Stem Control / Peripheral Mechanisms of Peristalsis / Central Versus Peripheral Mechanism of Deglutitive Inhibition / Neural Control of Longitudinal Muscle Contraction / Modulation of Primary and Secondary Peristalsis / Neural Control of Lower Esophageal Sphincter and Crural Diaphragm / Lower Esophageal Sphincter / Swallow-Induced LES Relaxation / Crural Diaphragm Contribution to EGJ and Neural Control / Transient LES Relaxation and Pharmacological Inhibition / Compliance of the EGJ / References

THE ESOPHAGUS The Esophagus investigates the anatomy, physiology, and pathology of the esophagus. This sixth edition, revised and updated throughout, also explores the diagnosis and treatment of various esophageal conditions. It includes treatment guidelines approved by the two largest gastroenterology societies, the ACG and AGA, as befits a work co-edited by two former presidents of those organizations. Advancements in diagnostics are presented, as are developments in the surgical and drug therapies. Presented in full colour, and boasting an unrivalled team of editors and contributing authors, The Esophagus Sixth Edition will find a home wherever the anatomy, physiology, and pathology of the esophagus are studied and taught. This book is accompanied by a website containing all the figures from the book in PowerPoint format. www.wiley.com/go/richter/esophagus6e Praise for the Fifth Edition: “There is absolutely no doubt that this edition of the textbook will maintain its status as the go-to reference for esophageal conditions, and will remain a highly utilized and clinically useful resource for novice and experienced physicians and surgeons alike.” (Gastroenterology, 1 July 2013)

While reflux disease, achalasia, esophageal spasm, gastroparesis and IBS include some of the most common disorders in all disease categories, the understanding of their pathophysiology has remained elusive. The field of clinical gastrointestinal motility has for decades relied on the measurement of intestinal movements for diagnosis and management of these difficult and enigmatic disorders of gut function. Although computers have increased the speed with which we can measure the movements of the gut, the devices to measure this movement have not changed in over 20 years. In the last 2 years, a new technologic breakthrough has taken place in the measurement of intestinal movement. The technology is called high resolution manometry. Rather than the old 4 and 8 channels systems of measuring pressure, high resolution employs 36 closely spaced solid state pressure transducers. By using this technology, the resolution of gut motor activity is incredible. This allows for better ways of viewing motility using color as pressure. This technology makes for beautiful images of gut motility that we have never seen before. We have made diagnoses that would never have been appreciated with the old technology. High resolution manometry is taking over conventional manometry worldwide and represents a dramatic leap in a long time stagnant area.

Principles of Deglutition is the first in class comprehensive multidisciplinary textbook to encompass the entire field of normal and disordered deglutition. It is designed as the definitive text for all those who desire to further their knowledge of the dynamic and expanding field of deglutology. The text is created to serve as a treasured reference for clinicians, educators and trainees from such diverse backgrounds as gastroenterology, speech language pathology, otolaryngology, rehabilitation medicine, radiology and others. Principles of Deglutition brings together the state-of-knowledge from 12 disciplines involved in dysphagia through contributions of over one hundred thought leaders and master clinicians for the benefit of patients and providers alike. It concisely organizes the wealth of knowledge that exists in each of the contributing disciplines into one comprehensive information platform. Principles of Deglutition provides a one-stop destination for members of all specialties to obtain state-of-the-art and critically reviewed information regarding deglutition physiology, pathophysiology, diagnosis and management. It delivers a comprehensive and in depth review of deglutition related cerebral cortical, brainstem, peripheral nerves, and neuromuscular mechanisms, advanced diagnostic modalities and standard of care and cutting edge medical, rehabilitative and surgical treatments. It is an essential reference for all deglutologists.

This book is a clinical manual that covers the whole spectrum of swallowing and its disorders. It starts with physiology of swallowing, pathophysiology of disordered deglutition, diagnostic methods (clinical and instrumental) and ends with an in-depth’s and up-to-date presentation of current treatment options. The clinically most relevant topics of dysphagia management on the stroke unit and the intensive care unit are dealt with in separate chapters. Also the closely intertwined issue of nutritional management is specifically addressed. Most importantly, the book covers all obligatory topics of the Flexible Endoscopic Evaluation of Swallowing (FEES)-curriculum, an educational initiative that started in Germany in 2014 and is currently being extended to other European and non-European countries. The book is richly illustrated and an online video section provides a number of typical patient cases. FEES is probably the most commonly chosen method for the objective assessment of swallowing and its disorders. It is used in stroke units, intensive care facilities, geriatric wards but also in rehabilitation clinics and within dedicated outpatient services. This book on neurogenic dysphagia therefore addresses a wide range of different medical disciplines, such as neurologists, geriatricians, intensive care physicians, rehabilitation physicians, gastroenterologists, otolaryngologists, phoniatrists and also speech-language pathologists.

This book offers one of the most comprehensive reviews in the field of gastrointestinal (GI) physiology, guiding readers on a journey through the complete digestive tract, while also highlighting related organs and glandular systems. It is not solely limited to organ system physiology, and related disciplines like anatomy and histology, but also examines the molecular and cellular processes that keep the digestive system running. As such, the book provides extensive information on the molecular, cellular, tissue, organ, and system levels of functions in the GI system. Chapters on the roles of the gut as an endocrine, exocrine and neural organ, as well as its microbiome functions, broaden readers’ understanding of the multi-organ networks in the human body. To help illustrate the interconnections between the physiological concepts, principles and clinical presentations, it outlines clinical examples such as pathologies that link basic science with clinical practice in special “clinical correlates” sections. Covering both traditional and contemporary topics, it is a valuable resource for biomedical students, as well as healthcare and scientific professionals.

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