Anatomiste de talent, Bartolomeo Eustachi a fait progresser cette science dans la seconde moitié du XVIe siècle. Outre la fameuse trompe d'Eustache, il a révélé l'existence de la valvule qui porte son nom, des surrénales, du canal thoracique.
Le grand oeuvre de Bartolomeo Eustachi devait être un traité d'anatomie « De dissensionibus ac controvesiis anatomicis ». Il devait comporter 47 planches anatomiques, dessinées avec l'aide de Pier Matteo Pini, richement détaillées et légendées. Seulement 8 planches furent publiées de son vivant. Les 39 autres, perdues, ont été longtemps recherchées. Elles ont été retrouvées 162 ans plus tard chez un descendant de Pier Matteo Pini. Publiées en 1714 sous le titre « Tabulae anatomicae Bartolomaei Eustachi quas a tenebris tandem vindicatas » (illustrations anatomiques de Bartolomeo Eustachi sauvées de l'obscurité), elles font de leur auteur, avecVésale, l'un des pères de l'anatomie moderne.
 
 
 
 
 
 
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mise à jour du
29 septembre 2005
Acta Oto laryngologica
(Stockholm)
1953;43(2-3):267-270
Yawning with regard to the respiratory organs
and the ear
A. Laskiewicz, London

La trompe d'Eustache  

Chat-logomini

Yawning is a complex somatical reflex serving the purpose of augmenting the tonus of the limbs and trunk muscles no less than the negative pressure in mediastinum, both of which agents elicit the outflow of venous blood from the perifery to the heart. From this point of view we can easily understand the nature and purpose of the stretching movements of the limbs and the body accompanied the phenomenon in question. The forwarding factor in producing these reflexes is always weariness after hard work in connection with the decline of the general tonus and blood pressure so that even at awakening from a long rest prolonged yawning reflex dominates the clinical picture. Likewise the feeling of hunger and thirst, living in unaired rooms for a long time (oxygen deficiency) and especially acute anemic status after hemorrhages as well as resulting from the disturbances of general metabolism and blood circulation within the brain, are accompanied by yawning. In the second place yawning be considered as an expression of the feeling of exhaustion and weariness, analogous to the related automatical phenomenon of laughter expressing contentand selfreliance.
 
On the other hand we can sometimes observe yawning as a consequence of augmented nervous tonus during prolonged and anxious waiting. This also explains the fact that the eliciting factor of yawning could even be the imagination as well as the sight of a yawner. In the last case the unconscious process ocurs which is defined commonly as yawning by imitation and belongs to the mimical automatisms elicited by suggestion. The view of a yawner affects onlookers like infection just as laughing or weeping which elicit analogous psychic states in observe and particularly sensible (hysterical) persons as reflexes with sometimes a spasmatic tint (J. Schul tz, Jaspar, Hösslin)
 
The part taken in this reflex by the upper respiratory organs is very active: tonic contracture of the mimical muscles, enlarged nostrils, wide opening of the mouth, tonic contracture of the soft palate adhering strongly together with uvula to theposterior pharyngeal walI, lifting up of larynx opening and tightness of the glottis, tonic contracture of the diaphragma. The symptom, concerning the ear are as follows: Wide Opening of the Eustachius tube during forced and prolonged yawning causes a great amount of air to be driven into the middle ear which press towards the fenestra. This fact elicits changes in the periendolymph pressure marked by a considerable hardness of hearing for low and middle tones and noises. Tympanophony, in yawning is characteristic for the patulous Eustachius tube.
 
In order to prove the influence of yawning on the variations of air pressure in the tympanal cavity I have chosen 5 cases of tympanic membrane scars, being situated mainly in the posterior part of the tympanic membrane movable and not adherent to the tympanal cavity. During deep inspirium these scars are subject to floating movements. in yawning they yield inwards. The short expirium is responsible for pushing out the whole tympanal membrane, which could be easily observed by using the anastigmatic otoscope of Brünings. The said movements I have tried to register with help of one Ear manmetter resembling the one used by Politzer for the same purpose. It is a glass tube of 1 mm inner light diameter, U shaped, 15 cm long and with 5 cm between the branches. The horizontally inflected branch is connected with a small rubber tube and protected by one olive end, which could be easily introduced in the external auditory canal and tightened with a piece of wool impregnated with glicerin. Alcohol-fuchsine solution was placed in the lumen of this mannometer.
 
The level of this fluid enabled us to read the variations of airpressure, in the external auditory canal as a consequence of movements of the tympanic. membrane and so with help of the background milimeter scale the diagram could be established, which illustrate approximatively the problem in question. The said variations depend mainly on the changes of airpressue in the nasopharynx during deep inspirium and swallowing (v. Dieshoecker Hammerschlag had asserted that the state of the vessels of the tympanal mucoso exercise a certain influence on the said airpressure. When the yawn as deep inspirium through the nose and a short expirium by the mouth the diagram of the airpressure shows lengthened contours from the upper to the lower end. The amount of air passing into the tympanal cavity is nearly the same as during swallowing. In rest the Eustachius tube is closed. The tightness of its lumen is not absolute while a pressure of 30-60 cm of water is able to penetrate this closure resistance when performing the tests of Politzer or Valsalva. The reverse direction in cases of an overpressure in the tympanum is much easier to penetrate j. e. with a pressure of + 12 cm only. This attribute is to be called the "valve mechanisme" of the Eustachius tube, which explains many disturbances of the ear during flying and their prevention by yawning or swallowing.
 
Rising to the altitude of 300-400 m as well as quick descent from it to scalevel produce protracted and repeated yawning as a defense reflex from the ear. Catarrhal inflammations of the throat and the nasopharyngeal cavity especially: pharyngitis chronica granulosa diffusa et retroarcualis could be the starting point of the yawning reflex with strong contractions of the palatal and throat muscles a phenomenon which might be appreciated by the Ear as a prolongated inspirium. Moreover I could state in these cases the phenomenon of aeophagia on the end of the inspiratory phase as it was confirmed by the X ray graphy.
 
From the intracranial complications often occurring with yawning reflex should be mentioned: inflammatory processes and neoplasms in the posterior cranial fossa, especially cerebellar abscesses and abscessus of the internal auditory meatus with circumscribed inflammatory processes of the meninges in the immediate vicinity of porus ac. mt.
 
Description of two cases of cerebellar abscesses in the course of acute supurative middle Ear inflammation and one case of abscess of the internal auditary meatus as a consequence of the purulent labyrinthitis healed by labyrinthectomy m. Neumann II with chiseling of the posterior margin of this auditory meatus, in which repeated and protracted yawning was one of the important neurological symptoms during the period of these abscesses in question.
 
The inflammatory processes in the region of mesencephalon are seldom joined with yawning, contrary to the posterior cranial fossa. Markl and Jedlieka have described a case of infiltration of the right thalamus of syphilitic origin spreading the capsula int. as a great rarity in literature. Clinical examination has stated a complete paresis of the left half of the body with involvement of the III rd, VI th, VII th and XII th nerves. During protracted and repeated yawning a synergy could be stated in the form of contraction in the elbow of the paretic extremity, attesting the influence of the motoric centres of the opposite hemisphere (left) stimulated by failing restraining action of the pyramidal fibres. A case described by O. Fischer deserves attention relating to the changes in the basal ganglia thalamus and corpus striatum on the underlying encephalithic process in which the yawning reflex did not appear at all, and also the related automatical movements of mastication, laughing and swallowing were absent. This fact has given a fundamental base to Bertolotti and Vogt who suppose that yawning as a mimical automatism has its own centre in the basal ganglions especially in the region of corpus striatum i. e. the nucleus caudatus and putamen. H Levy shares this opinion observing analogous subsisting of automatical movements in the course of paralysis agitans and stressing that the overpart of the brain cortex is not necessary for the purpose of eliciting these reflexes.
 
Radiopaque contrast dye in nasopharynx reaches the middle ear during swallowing and/or yawning
Winther B et al
Acta Oto-Laryngologica
2005; 125: 625-628 
 
The role of the Eusatchius tube and the tympanal muscles in yawning
Laskiewicz A
Revue de Laryngologie Otologie Rhinologie
Mai-Juin 1953 74° année; n°5-6
 
Yawning with regard to the respiratory organs and the ear
Laskiewicz A
Acta Oto laryngologica (Stockholm)
1953; 43; 2-3; 267-270
 
Remarques sur la signification physiologique du bâillement
Lepp FH
Bull Group Int Rech Sci
Stomtol Odontol
1982; 25; 251-290
 
Evaluation of Eustachian tube function by sonotubometry: results and reliability of 8 kHz signals in normal subjects
Di Martino EF, Thaden R, Antweiler C,et al.
Eur Arch Otorhinolaryngol. 2006
 
Joseph Toynbee (1815-1866) of England wanted to do more work with otology. He dissected more than 2000 temporal bones and formed the collection which became known as the Toynbee Collection in the Museum of the Royal College of Surgeons. In 1860, his work "Disease of the Ear" was published. It contained information on the dissection of diseased ears. Toynbee showed that stricture of the Eustachian tube was not a common affliction since he had only one out of his 1523 dissections. He noted that the Eustachian tube was not permanently open, but lightly closed, and that it became opened only during such movements as swallowing or yawning. In one of his dissections, Toynbee recognized a fistula of the external semicircular canal and he pointed out that infection could extend to the brain by way of the labyrinth. Tonybee was one of the first to describe otosclerosis (a condition characterized by chronic progressive deafness) and he recognized it in 160 cases.