Videofluoroscopic swallowing exam: Technique, imaging findings and clinical implications.

Transcription

1 Videofluoroscopic swallowing exam: Technique, imaging findings and clinical implications. Poster No.: C-2088 Congress: ECR 2015 Type: Educational Exhibit Authors: L. Anton Mendez, A. M. Ibañez Zubiarrain, J. Cardenal Urdampilleta, J. Castillo de Juan, M. Udondo Gonzalez del Tanago, R. Zabala Landa, D. Grande Icaran ; Bilbao/ES, 2 Barcelona/ES Keywords: Swallowing disorders, Motility, Diagnostic procedure, Fluoroscopy, Stomach (incl. Oesophagus), Head and neck, Gastrointestinal tract DOI: /ecr2015/C-2088 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 22

2 Learning objectives -To remember the main anatomic and physiologic aspects of the swallowing process. -An approach to the videofluoroscopic swallowing examination technique, emphasizing on the choice of different contrast viscosities according to the indication of the study. -To provide a pictorial review of both physiological and pathological videofluoroscopic findings in each of the four swallowing phases. Page 2 of 22

3 Background Swallowing is a complex process which must accomplish two main objectives: transporting the food from the oral cavity to the oesophagus, and protecting the entrance of the airway while this transport occurs. The principal anatomical structures that take part on it are shown in the Fig. 1 on page 5. The swallowing is divided into four stages (Fig. 2 on page 5): Oral preparatory phase: The bolus is located in the oral cavity, between the tongue and the palate. The glossopharyngeal junction remains sealed so it cannot go into the pharynx. Oral propulsive phase: The tongue moves in an anterosuperior direction pressing against the palate, which causes a backwards movement of the bolus toward the oropharyngeal junction. Pharyngeal phase: Hyolaryngeal complex moves in an anterosuperior direction to prevent the entrance of the airway from being into the trajectory of the bolus and, moreover, to make the cricopharyngeus muscle (upper oesophageal sphincter) open. Larynx and velopharyngeal junction also get closed. A wave of contraction with a vertical direction (from upper to lower constrictor muscles) occurs, which eases the bolus clearance towards the oesophagus. Oesophageal phase: When the bolus crosses the upper oesophageal sphincter into the cervical oesophagus, the sphincter closes and the structures of the pharynx and larynx return to their initial position. Airway opens again. We can divide the pathology of swallowing into two disease groups, depending on which of the two previously mentioned functions of the process fails: Efficacy disorders: A portion of the bolus (or the entire bolus) fails to arrive to the oesophagus. Safety disorders: Part of the bolus (or the entire bolus) enters the airway. Approaching the diagnosis: Role of videofluoroscopy Evaluation begins by asking the patient about his medical history, which usually helps to define the possible causes of his problem. Page 3 of 22

4 The following step is an accurate clinical examination. Then there can be used some instrumental techniques, where the videofluoroscopic swallowing exam (VFSE) plays an important part. It provides live imaging of the four phases of the swallowing process that allow the assessment of the width and speed of movement of the anatomical structures as well as their coordination, so we can subsequently establish the specific stage and location of the problem. Using both clinical and radiologic data, we usually are able to establish the diagnosis. Sometimes the pathology is caused by some specific food consistencies, while a more or less thick same food quantity is well tolerated. Performing a VFSE provides us with not only the anatomic structures where the problem takes place and the kind of pathology, but also the food consistency that triggers it. This, besides for diagnosis, is paramount when we need to approach the proper nutrition for the patient, because we will know which consistencies we are able to administer without any risks. In the next lines we will present the technique and the main, both physiological and pathological, findings on a VFSE. Page 4 of 22

5 Images for this section: Fig. 1: Anatomy of the main structures involved in swallowing. Wikimedia Commons. Modified "Pharynx diagram-fr.svg". You can find commons.wikimedia.org/wiki/file:pharynx_diagram-fr.svg?uselang=es Page 5 of 22

6 Fig. 2: Phases of swallowing: A. Oral preparatory phase B. Beginning of oral propulsive phase C. Oral propulsive phase-beginning of pharyngeal phase D and E. Pharyngeal phase F. Oesophageal phase Hospital Sant Joan de Deu. From the article La disfagia y el paciente neurológico by Meavilla S, Pinillos S. Page 6 of 22

7 Findings and procedure details Positioning and acquisition The patient is placed standing, in a lateral position. Following the experience of our centre the lateral projection is enough to achieve an optimal imaging of the structures in most of cases, therefore it is the only positioning included in our routine protocol. We reserve the oblique and anteroposterior projections for specific cases, for example when any asymmetries are suspected. We use a high image acquisition rate (30 images per second). In contrast to what it may seem, it has been reported that a high rate reduces the possibilities of overlooking subtle findings, so we need fewer swallows to reach a reliable diagnosis. This shortens the length of the study, and thus reduces the overall radiation and makes the examination more comfortable for the patient (sometimes it is quite difficult to prevent the patient from losing his patience along the examination). If the clinical suspicion includes any tumoral pathologies, or the radiologic findings suggest it, it is indicated to practise an oesophagogram immediately after the swallowing exam due to the association between neck and oesophageal tumours. Procedure The protocol of our institution is based on the model described by Clavé P et al. We use three different contrast viscosities: pudding, nectar and liquid (from thicker to less thick). We add a concrete quantity of a thickening agent (Nutilis powder from Nutricia in our institution) to a low-density barium suspension. High osmolar iodine-based contrasts are not recommended in a suspicion of aspiration because of their reported risk of chemical pneumonitis. We may initially use a water-soluble contrast in patients who have undergone surgery to assess for anastomotic leaks. To obtain each viscosity, the thickener amounts that must be added are: Pudding: 8 g. Page 7 of 22

8 Nectar: 3'5 g. Liquid: 0 g (No thickener added). (Optional) Honey: 5 g. Not in our main protocol, can be used for the assessment of an intermediate thickness. A complete VFSE consists of 9 swallows. We administer increasing volumes of contrast (5, 10 and 20 ml) of each contrast viscosity, beginning with nectar. If no security disorders are noticed with the first amount (5 ml), we continue with the second (10 ml) and then with the third (20 ml). Then, after completing the study with nectar viscosity, we begin again from the first amount, now administering liquid viscosity. When the examination with liquid viscosity is finished (with no findings), we consider that there are no security disorders, so the administration of any food consistence is safe. After this, we can continue the examination with the pudding viscosity if we want to assess the efficacy of a high-density food swallowing. If a security disorder is noticed within the study, we write down the viscosity and amount which have caused it. From here, we must not administer any higher volume of the same thickness, nor any volume of a lower viscosity contrast. If we want to keep on with the examination, it must be by administering only a higher viscosity. We follow these criteria because we understand that in a patient who suffers from oropharyngeal dysphagia, the aspiration risk increases with lower food densities and higher food volumes, so we take for granted that aspiration will also occur if we decrease the density or increase the amount given. Pathological findings The following are the main swallowing disorders we can find: Efficacy disorders Oral (preparatory and propulsive) phase: Decreased labial closure: contrast falls from the mouth. Page 8 of 22

9 Swallowing apraxia: difficulty, delay or inability to start the process (often in neurologic diseases, most common after a stroke). Lingual control and propulsion disorders: the bolus is not correctly formed and there can be seen a residue in oral cavity or valleculae. Pharyngeal phase: A symmetric residue in both piriform sinuses is caused by a weak pharyngeal contraction and usually found in neurologic patients. It also predisposes to aspiration. An asymmetric residue in piriform sinuses is often consequence of an unilateral pharyngeal paralysis. Cricopharyngeal disfunction: the contrast does not penetrate the oesophagus, accumulates in hypopharinx and highly predisposes to security disorders. Security disorders Oral phase: Palatoglossal seal dysfunction: bolus falls to hypopharynx while the airway is still open, which causes a predeglutory aspiration. Pharyngeal phase: Penetration: the contrast enters the laryngeal vestibule, without overflowing the vocal chords. Aspiration: the contrast overflows the vocal chords and gets into the trachea. Lack of coordination of swallowing movements, for example the delay on the closure of laryngeal vestibule which implies a high aspiration risk. The report Although the ideal would be the presence along the examination (beside the radiologist) of a clinician specialized in oropharyngeal dysphagia, this usually isn't possible. This makes crucial the development of a good report by the radiologist so that the clinician can, after reading it, understand which is the problem and, from that point on, approach his attitude on the most accurate way. After our experience, a complete VFSE report, under our point of view, must include: Page 9 of 22

10 Pre-test clinical suspicion, based on the previously made clinical examination and medical history. Kinds of contrast viscosities and amounts given. Found security or efficacy disorders, being important to specify which kind and amount of contrast we have administered for each disorder to occur. If a security disorder (mainly aspiration) happens, we should strive to note if it occurs before, during or after the swallowing. Stage where the disorder occurs, if possible. We must indicate if the patient showed any clinical sign or symptom during the examination (for example, cough), specially if a security disorder was present. Page 10 of 22

11 Images for this section: Fig. 3: Videofluoroscopy of a normal swallowing, where the four phases can be differentiated. Osakidetza, H. U. Basurto - Bilbao/ES Page 11 of 22

12 Fig. 4: Security disorder: penetration. We increased the amount of contrast (from 5 to 10 ml of liquid density) in the patient of the Fig 3, and this is what it happened. Osakidetza, H. U. Basurto - Bilbao/ES Page 12 of 22

13 Fig. 5: Security disorder: nasopharyngeal reflux of the bolus due to an insufficient closure of velopalatine junction. Penetration and pharyngeal residue also can be noted. Osakidetza, H. U. Basurto - Bilbao/ES Page 13 of 22

14 Fig. 6: Efficacy disorder: apraxia and fractioned swallowing in a neurologic patient. Osakidetza, H. U. Basurto - Bilbao/ES Page 14 of 22

15 Fig. 7: Anteroposterior projection in the same patient as in Fig 6 reveals a symmetric residue into piriform sinuses. When swallowing begins, a left pharyngeal diverticulum can be seen. Both are efficacy disorders. Osakidetza, H. U. Basurto - Bilbao/ES Page 15 of 22

16 Fig. 8: Efficacy disorder: capture from a videofluoroscopic examination in anteroposterior projection where a symmetric residue in valleculae can be noted. Osakidetza, H. U. Basurto - Bilbao/ES Page 16 of 22

17 Fig. 9: Security disorder: aspiration. A failure in the pharyngeal clearance causes a pharyngeal residue that first enters the laryngeal vestibule (penetration) and then, during the next swallow, makes an aspiration. Osakidetza, H. U. Basurto - Bilbao/ES Page 17 of 22

18 Fig. 10: Conventional radiography of the Fig 9 patient, where the presence of contrast in the trachea and main bronchi is clearly seen. Osakidetza, H. U. Basurto - Bilbao/ES Page 18 of 22

19 Fig. 11: Security disorder: aspiration. Although the name is the same, the mechanism is completely different from the one in Fig 9. In the actual image, aspiration happens immediately in the pharyngeal phase, because of a delay in the laryngeal closure movements that causes the direct entrance of contrast into the airway. No pharyngeal residue is present. Osakidetza, H. U. Basurto - Bilbao/ES Page 19 of 22

20 Fig. 12: Clinical sign: cough. During the examination the patient suffers from a cough attack. Note that it happens immediately after a mild penetration. Osakidetza, H. U. Basurto - Bilbao/ES Page 20 of 22

21 Conclusion -Swallowing is a four-phase divided process where a number of coordinated anatomical structures take part. -Videofluoroscopy is one of the basic pillars for the diagnosis of swallowing disorders, along with the clinical examination. -It gives us the chance to specify, besides many other important aspects, the concrete food viscosity that causes the swallowing disease. -It is essential to develop a complete report so that it can guide the clinical attitude. Page 21 of 22

22 References Diagnóstico y tratamiento de la disfagia orofaríngea funcional. Aspectos de interés para el cirujano digestivo. Clavé P, Arreola V, Velasco M, Quer M, Castellví JM, Almirall J et al. Cir Esp 2007;82(2):62-76 Abordaje clínico de la disfagia orofaríngea: diagnóstico y tratamiento. Velasco MM, Arreola V, Clavé P, Puiggrós C Nutr Clín Med 2007;1(3): Oropharyngeal dysphagia: patophysiology and diagnosis for the anniversary issue of Diseases of the Esophagus. Logemann JA, Larsen K. Dis Esophagus 2012 May;25(4): Evaluation and treatment of swallowing disorders. Logemann JA. 2nd ed. Austin, TX: Pro-Ed, The effect of bolus viscosity on swallowing function in neurogenic dysphagia. Clavé P, De Kraa M, Arreola V, Girvent M, Farré R, Palomera E, Serra-Prat M. Aliment Pharmacol Ther 2006; 24(9); Page 22 of 22