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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
20 février 2003
 Revue de Laryngologie Otologie Rhinologie
G Portmann
Mai-Juin 1953
74° année; n°5-6
La trompe d'Eustache
The role of the Eustachius tube
and the tympanal muscles in yawning
A Laskiewicz
London

Chat-logomini

 
On a discuté de l'anatomie et de la physiologie de la trompe d'Eustache. Les observations salpingoscopiques ont prouvé que le tube Ostium pharyngeum s'ouvre largement à chaque bâillement; une grande quantité d'air est donc poussée dans la cavité tympanale. Ce phénomène est marqué par une dureté d'oreille considérable, des bruits graves, de l'autophonie causée par l'augmentation de la pression d'air vers la fenêtre et la membrane tympanale dont les mouvements pourraient être enregistrés à l'aide du manomètre à oreille de Politzer.
 
Le diagramme des mouvements en question est très différent quand nous bâillons par une profonde aspiration par le nez et une courte expiration par la bouche.
 
La perte de son du muscle ptérygoïde interne dans la subarthrose, dysarthrose et dans les mâchoires édentées, influence de la même façon les muscles tensor veli palatini et tensor tympani, causant une diminution de l'aération de l'oreille moyenne avec une déperdition de l'ouïe consécutive, ca.15-20db.
 
Quant à la disparition rapide de la surpression dans la cavité tympanale pendant le bâillement juste à la fin d'une expiration prolongée, la contraction du muscle tensor tympani est responsable de ce phénomène. Le relachement du dit muscle dans le bâillement comme accompagnement de la contraction et du relâchement du muscle orbicularis oculi présente une diiminution relativement lente jusqu'à ce que le muscle soit détendu complètement. L'enregistrenient du changement de tension du muscle tensor tympani pourrait être essayé en mesurant les impédances acoustiques de l'appareil de transmission après l'irritation de l'oreille donnée par des sons forts ou intermittents, comme l'ont prouvé 0. Metz, Perlmann et Casse.
Yawning is a somatical reflex serving the purpose of augmenting the tonus of the limbs and trunk muscles no less than the negative pressure in the mediastinum, which promotes the outflow of venous blood from the filled-up veins of the distant parts of the body. It also must be considered as an expression of the feeling of exhaustion and weariness. An organ taking an active part in yawning is the Ear. It is a common knowledge that as long as one yawns nothing can be heard, and when the yawning reflex is finished the hearing returns quickly. The explanation of this phenomenon must be sought in the relation between the mechanism producing opening of the Eustachius tube to the aeration of the tympanal cavity as well as the contraction of the tensor tympani and stapedius muscles in yawning. The Eustachius tube forms a funnel-like canal leading from, the naso-pharynx to the midde Ear an extent of ca. 35 mm in the adult. The diagonal course of its half inch short bony part and the angular descent of ca. 40 degrees from the horizontale i. e. the base of the skull of its 3 lines longer cartilagineous part forms some complicating topography of the tube in question.
 
The cartilagineous portion when seen in cross section looks like a sheperd's crook (Hirtenstabkrummung of the German authors). The short lateral cartilage serve as a fine of insertion for the tensor veli palitini (m. spheno-salpingostaphylinus), arising from fossa scaphoidea of the sphenoid bone. Levator veli palatini, forming the bottom of the tube starts from the inferior apical part of the pyramidbone and then is called petrosalpingo-staphylinus.
 
Urbantschitsch has compared the lumen of the tube to the flat double pens the narrowing of which (istmus) shows many variations. The collapsed soft tissue (pars membranacea) of the pharyngeal end of the Eustachius tube is believed by Armstrong to close its lumen when the mentioned muscles are in rest (flutter valve mechanism). On swallowing or yawning the tensor veli palatini opens booldike the walls of the Eustachius tube while the bulge of the levator veli palatini supports the separation of its walls. The nerves supplying tensor tympani, levator, tensor-veli palatini and pterygoideus intern. muscles derives from the anterior part of the 3d branch of trigeminus (portio minor trigemini or nervus masticatorius). Therefore the synchronisation of their innervation inspite of many differences consists in their motion. The loss of tone of the pterygoideus. int. muscle, which appear often in cases of malformation of the temporo-mandibular joint as s.c. subarthros and dysarthros in edentelous jaws, influences in the same way the tensor veli palatini and tensor tympani muscles. Thesefunctiona] changes are manifested by the diminished aeration of the middle Ear on the given side with noises, tinnitus, loss of hearing for whisper, speech and tunning forks under 4000 Hz. The acrylitic splint fort the purpose of completing the edentelous bite applied by Ronkin in these cases, had increased the tonus of pterygoideus int. muscle through the head noises and tinnitus has markedly decreased, rough which the 15 db. improvement of hearing was reached.
 
Change of tonus of levator veli palatini m. has been described by Gyergay with susbsequent wide opening of the Eustachius tube during swallowing, which causes a greater amount of air to be driven into the middle Ear than is necessary for compensation of the negative air pressure there.
 
Salpingoscopie observations proove that the ostium pharyngeum tubae opens widely in yawning or swallowing by retraction of its anterior wall. Repeated swallowing reveals that the closed ostium does not open every time. In yawning however it opens every time to such an extent that a great amount of air is driven into the tympanal cavity. This phenomenon is marked by a considerable hardness of hearing low noises, autophony caused by increased air pressure towards the fenestra (rotundum and ovale) as a compliant part of the rigid wall of the tympanal cavity. This fact elicits changes in the peri-endolymph pressure, lasting as long as the superflous amount of air is discharged by the action of the tympanic muscles : tensor tympani, stapedius. In order to prove the influence of yawning on the variations of air pressure in the tympanal cavity as well as the action of the tympanal muscles in yawning I have tried to register the movements od the tympanal membrane with the help of an Ear manometer resembling the one used by Politzer.
 
The level of alcohol-fuschin sol. placed in the lumen of the U shaped glass tube of this manometer enabled us to read the variations of air pressure in the external auditory canal as a consequence of movements of the tympanal membrane in yawning With help of the background mililmeter scale the diagram could be established, which illustrates approximately the problem in question. When we yawn as a deep inspirium, through the nose and a short expirium by the mouth, the diagram of the tympanal membrane movements shows a lengthened contours from the upper to the lower end. It is evident that the ostium of the Eustachius tube is principally closed and the resistance of it closure could be proved by the imethod of Zöllner (overpressure in the nasopharynx and simultaneously observing the movements of the Eardrum) and the method of v. Dishoeck by using of pneumophone. The said autbor has prooved that the pressure 30-60 cm of water in Valsalva or Politzer test, is able to overcome this resistance, on the contrary the overpressure in the tympanic cavity caused by swelling or catarrhal inflammation of the tympanal mucosa pass easier through the tightness of the obstructed tube by using 12 cm of water only. The air caught in the typanum will be resorbed til itequals the pressure of the blood-gasses. Partial pressure of the capillary bloodgasses are : Oxygen.... 90 cm of water;... 800 cm w.; CO2 60 cm; total 950 cm w . Atmospheric pressure on the outside of the tympanal membrane amounts 1000 cm. of water; the differential negative pressure in the tympana cavity is approximatively 50 cm of water which could be easily proved by using of the mentioned pneumophone and the hearing disturbances establislied mainly for the frequencies under 4000 Hz. as 15-20 db. loss. The high tones are improved in negative as well as in positive pressure differences in the tympanic cavity. It is striking that the overpressure in the tympanuin in yawning in normal individuals causing a considerable hardness of hearing disappears quickly just a the end of the prolonged expirium in this phenomenon.
 
The explanation of this fact must be sought in the contraction of the tensor tynipani muscle which facilitated the expulsion of the superflous amount of air from the tympanal cavity. The start of the contraction in question is synchronous with levator and tensor veli palatini, but the relaxation of the tympanal muscle is not contemporary with the said muscles. Perlmann, Casse and Metz have proved that the relaxation of the afore mentioned muscle after irritation of the given Ear with strong or interrupted tones, lasts relatively long until this muscle unbends completely. Likewise, the spontaneous contraction of tensor tympani m. in yawning as a concomitant to that of orbicularis, oculi m. presents a much more slow decrease of the contraction curve than when it is produced acoustically. This could be tested by the registration of the change in the tension of the tympanal membrane rneasuring acoustic impedances of the transmission apparatus, which is to be compared with avariable acoustic impedance standard and the Ear of the examiner as it was described by 0.Metz ( in Acta Oto-Laryngol., Supplementum 63, and vol. XXXIX, f. 5). This apparatus consists, of a tube ends of which are adapted to the Ear of the subject and the opposite one to the examiners. The telephone-membrane placed in the mesial part of this tube sounds to either side. By means of a Y shaped glass-tube this acoustic bridge is connected with audio-oscillator, piezo-electric microphone, amplifier and the string oscillo-graph. The opposite Ear of the subject is attached to the audiometer-telephone as a source of acoustic stimulus, producing, the change in the tension of the tympanic membrane. According to Lorente de No this unilateral acoustic stimulus elicit bilateral contraction of tensor tympani m. resembling a pupillary reflex.
 
The intensity of tone from audio-oscillator at the detector (piezo-electric microphone-amplifier and oscillograph) gives approximately a notion of the change in impedance of this acoustical transmission, caused by the contraction of the tympanal mscle. In order to test changes in tension of the tympanic membrane related to the contraction of the tensor tympani muscle in yawning an audiometer telephone could be eliminated from the above described apparature used by 0. Metz and replaced by a rubber tube only, joining this Eaar with the main tube. By using such a simplified apparatus oscillogiaphic records of changes in the impedance of the tympanic membrane could be given, produced by contraction of the tensor tympani muscles in yawning. This sound curve shows a slow rising, and ceases just as slowly as the analogous one produced acoustically by 0. Metz.
 
This oscillographical record-cuve of the impedance in question confirms the supposition, that the prolonged contraction and relaxation of the tensor tympani muscle, lasting for a long time just after the ceasing of expirium phase in contributes in a great measure to the expulsion of the superflous amount of air from the tympanal cavity by which a « quick Ear » is promptly restored. This, function of the mentioned muscle meets with no obstacles in view of the fact that the pressure of 12 cm of water only is required to combat the resistence of the Eustachius tube starting from its tympanal ostium outwards. The same experiment repeated in the opposite direction requires 3-4 times greater an effort.
trompe_eustache
 
 
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.