Anatomy, physiology and pathophysiology of dysphagia.
ABSTRACT This is a review paper examining the pathogenesis of oropharyngeal dysphagia. Pharyngeal anatomy and physiology are discussed along with a detailed description of the neuronal architecture and function of the medullary swallowing center. The oropharyngeal swallow is then examined in biomechanical terms emphasizing that the swallow is comprised of several elements (velopharyngeal closure, upper esophageal sphincter opening, closure of the laryngeal vestibule, tongue loading, tongue pulsion and pharyngeal clearance) each of which can be compromised, causing dysphagia. The key modality for evaluating patients with oropharyngeal dysphagia is the videofluoroscopic swallowing study which is analyzed according to the efficacy with which these functional elements of the swallow are accomplished. Specific therapy can then be addressed toward correcting dysfunctional elements.
- SourceAvailable from: Roberto Grassi[show abstract] [hide abstract]
ABSTRACT: Dysphagia is a symptom of different pathological conditions characterised by alteration of the swallowing mechanism, which may manifest at different levels. We report our experience in the evaluation of the swallowing mechanism with combined videofluoroscopy and manometric recordings. For the combined study, we used a Dyno Compact computerised system (Menfis Biomedical s.r.l., Bologna, Italy) equipped with: (1) graphics card for the management of ultrasonographic or radiological images; (2) A.VI.U.S. dedicated software package, which enables digital-quality recording (PAL/NTSC, composite video or S-Video) of the videofluoroscopy study in AVI format with 320 x 240 resolution and 25 Hz acquisition frequency. The delay introduced by the process of image digitalisation is in the order of 200 ms, so for analysis purposes, the images can be considered synchronised with the manometric recordings. The videomanometry study was performed with the administration of contrast material either in bolus form or diluted. Data were collected on a specifically designed grid for the evaluation of 46 videofluoroscopic items, of which 34 are derived from the laterolateral view (seven in the oral preparatory phase, 15 in the oral transport phase and 12 in the pharyngeal phase) and 12 in the anteroposterior view (six in the oral preparatory phase and six in the oropharyngeal phase). A positive finding for the individual parameters is expressed in a binary fashion. Manometric evaluation was based on 11 items divided into four major and seven minor criteria. Dynamic videofluoroscopy swallow study combined with concurrent manometry enabled the simultaneous recording of anatomical alterations and the functional data of oropharyngeal pressure, thus providing a picture of the anatomical, biomechanical and physiological conditions of swallowing and the manner of bolus propulsion and transit. An early and effective diagnosis of oropharyngeal dysphagia means being able to effectively implement appropriate rehabilitation techniques, improve the patient's quality of life, and minimise the complications associated with swallowing disorders (choking, aspiration pneumonia, malnourishment). Distinction of the anatomical level of dysphagia is not a matter of simple classification; rather, it is essential in that different clinical presentations require different diagnostic strategies, and a precise definition of the anatomical-functional substrate is required to implement the correct therapeutic approach. This study presents the authors' experience with the use of combined videofluoroscopy and manometry with particular emphasis on the examination technique.La radiologia medica 07/2008; 113(6):923-40. · 1.46 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: To date, the details of human sensory innervation to the pharynx and upper airway have not been demonstrated. In this study, a single human oro- and laryngopharynx obtained from autopsy was processed with a whole-mount nerve staining technique, Sihler's stain, to determine its entire sensory nerve supply. The Sihler's stain rendered all mucosa and soft tissue translucent while counterstaining nerves. The stained specimen was then dissected and the nerves were traced from their origins to the terminal branches. It was found that the sensory innervation of the human pharynx is organized into discrete primary branches that innervate specific areas, although these areas are often connected by small neural anastomoses. The density of innervation varied, with some areas receiving almost no identifiable nerve supply (e.g., posterior wall of the hypopharynx) and certain areas contained much higher density of sensory nerves: the posterior tonsillar pillars; the laryngeal surface of the epiglottis; and the postcricoid and arytenoid regions. The posterior tonsillar pillar was innervated by a dense plexus formed by the pharyngeal branches of the IX and X nerves. The epiglottis was densely innervated by the internal superior laryngeal nerve (ISLN) and IX nerve. Finally, the arytenoid and postcricoid regions were innervated by the ISLN. The postcricoid region had higher density of innervation than the arytenoid area. The use of the Sihler's stain allowed the entire sensory nerve supply of the pharyngeal areas in a human to be demonstrated for the first time. The areas of dense sensory innervation are the same areas that are known to be the most sensitive for triggering reflex swallowing or glottic protection. The data would be useful for further understanding swallowing reflex and guiding sensory reinnervation of the pharynx to treat neurogenic dysphagia and aspiration disorders.The Anatomical Record 05/2000; 258(4):406-20.
- [show abstract] [hide abstract]
ABSTRACT: Orally disintegrating tablets (ODTs), also known as fast melts, quick melts, fast disintegrating and orodispersible systems, have the unique property of disintegrating in the mouth in seconds without chewing and the need of water and are thus assumed to improve patient compliance. Conventional methods like direct compression, wet granulation, moulding, spray-drying, freeze-drying and sublimation were used to prepare ODTs. New advanced technologies like Orasolv®, Durasolv®, Wowtab®, Flashtab®, Zydis®, Flashdose®, Oraquick®, Lyoc®, Advatab®, Frosta®, Quick-Disc® and Nanomelt® have been introduced by some pharmaceutical companies for the production of ODTs. The main objective of this review is to give a comprehensive insight into conventional and recent technologies used for the preparation of ODTs.Acta Pharmaceutica 06/2011; 61(2):117-39. · 1.16 Impact Factor