Functional morphology of phonation evaluated by dynamic MRI

The complex anatomy of the larynx is a consequence of its various airway functions. The aim of the present study was to evaluate which anatomical structures of the larynx soft tissues could be defined using MRI, and to investigate the feasibility of using this technique to assess the dynamic functions of the larynx. MRI images of the larynx of six healthy volunteers during speech production were obtained in vivo. The volunteers were asked to breathe out long and deep in order to prolong in a normal voice the emission of the vowels [i] (as in key) and [a] (as in car) and the consonant [ch] (as in ship). We demonstrated the modification of the larynx position, which is high for [i] and low for [a], and the modification of the vocal folds which is adducted and abducted in [i] and kept abducted in [ch]. Dynamic MRI allows the possibility of multiplanar high-resolution imaging. It can provide information about the anatomy of the larynx and, it also has the ability to image moving laryngeal structures and to analyze vocal fold vibrations during phonation.

[The temporo-mandibular articulation]

The standing posture of humans has created both morphological and functional adaptations in the temporo-mandibular joint and the masticatory function. This biped state is the one of the most important characteristic of human evolution. It is furthermore the agent determining most of the functional changes in the whole body. This survey will be carried out in several levels including, a descriptive anatomy, biomechanics, radiological imaging, functioning in the articulation of TMJ. The descriptive anatomic picture will be obtained by the traditional dissection techniques. 20 TMJ joints are dissected from 10 cadavers: 7 cadavers, 65-75 year old, 3 cadavers, 60-65 year old. The x-rays are lateral view and the subjects of the radiological imaging are young's, adults and olds: 1, 3 y-old Male; 1, 7 y-old Female; 1, 14 y-old Female; 10, 19-23 y-old Male; 1, 26 y-old Female; 1, 34 y-old Male; 1, 75 y-old Female. The anatomic elements in the TMJ well resembled the ones described in the literature of the capsule, the ligament, the masticator muscles (masseter, temporal, medial and lateral pterygoids). The temporo-mandibular ligament proved to be difficult to separate from the capsule in some of the specimens. Sometimes it was not always found after a dissection.

[Application of a new vascular injection technique in the study of the infratemporal region]

The infra-temporal region (ITR) is an anatomically rich region thanks to its arterial and venous divisions and large nerve crossroads. It is also, as described by Robert et al". in a publication about the ITR, (22) "the hidden face of the manductory apparatus. The ITR is therefore a passageway for a large number of anatomical elements and its complexity makes it a particularly delicate region for daily surgical practice. For these many reasons the anatomical study of the ITR, which has already been the origin of a number of works, seemed interesting to us, and more particularly combined with the use of an original injection material, Odongel. The injection of this material, in the arterial as well as the venous system, enabled us to improve our dissections thanks to its flexibility, elasticity, its case-of-use and its speed of preparation. The complexity and richness of the region meant that in order to study it anatomically we had to focus on a specific anatomical element for each dissection session, especially at the beginning. After having used traditional products such as resins (methyl methacrylate), latex and even the too rigid silicon elastomers, Odongel seemed interesting to us because it is very easier to use it. The purpose of this study was to prove that Odongel is an efficient material, working equally well for both the arterial and venous systems irrespective of the diameter of the vessels concerned. It can become an alternative to the other injection products in some situations. Finally, in the case of the ITR, an extension of the existing techniques used in anatomical studies coupled with an increase in anatomical precision could improve our knowledge of this zone and eventually facilitate certain surgical interventions.

[The maxillary sinus: evolution and function in aging]

The maxillary sinus, or Highmore's antrum, is located in the maxillary bone. The maxillary, above the buccal cavity, below the orbital cavity and outside the nasal fossa, is going to take a part in the formation of the three cavities which surround it. Although voluminous, it is consists of a light bone. This distinctive feature is essentially due to the fact that the maxillary has a cavity. The maxillary sinus occupies the upper 2/3s of this maxillary bone. It is the largest of the facial structure's cavities. Its volume is very variable, depending on the individual, the condition of their edentulousness and their age. We find small, average or large sinuses. This sinus communicates with the corresponding nasal fossa by a canal. It opens at the level of the nasofrontalis duct by a meatic ostium, an ostium located at the top of the meatus nasi medius, i.e. under the floor of the sinus. This highly positioned drainage location easily explains the problems that sinus pathologies can come up against. The sinus is lined with a mucous membrane and we can point out that in the normal condition this mucous membrane adheres weakly to the bone. It is more or less thick as a function of the pathologies to which the sinus has been subjected, or even as a function of the geographical location where the individual lives. The imaging of this sinus as a function of age is not obvious due to the fact that it is invisible throughout embryonic and foetal development, and that it only becomes visible to X-rays relatively late, at about 6 years old. Its role is important at the level of the growth of the facial structure because it is always easier to have growth around cavities. It also has a mechanical role concerning the transmission of shockwaves during traumas. In old individuals, due to the condition of the edentulousness, the volume of the sinus is larger; in fact one can note the resorption of the alveolar bone. The maxillary sinus is a cavity which plays a very important role throughout an individual's existence because of the previously mentioned reasons, and which could be used during surgical reconstructions, by the partial filling of this space, to increase the quantity of usable bone (grafts...).

Study of the relationship between the suprascapular artery and the brachial plexus

The literature concerning the relationship of the suprascapular artery with the brachial plexus is quite limited. The aims of this study were to investigate the different types of relationships between the suprascapular artery and the brachial plexus trunks and to try to clarify their prevalence in the European population. Our study involved the dissection of 100 upper extremities from adults, all of European origin (55 women, 45 men). In the classic description, the suprascapular artery passes in front of the brachial plexus (group A) in the majority of cases, then behind the omohyoid before reaching the superior border of the scapula. There are two other types of relationship with the brachial plexus: the suprascapular artery can pass between the trunks of the brachial plexus (group B) or the artery can pass behind the brachial plexus (group C). To our knowledge there has been only one study on the subject, carried out by Kosugi et al. Our results show a not inconsiderable number of variations in the relationships between the suprascapular artery and the brachial plexus (29%). Although no differences were noted between the sexes, a significant number of individual variations were revealed by the comparative study of dissections performed on both upper extremities of the same individual. Our results suggest that new studies are required to complete these initial anatomical results observed on a small sample of subjects of European origin. The French version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00276-002-0026-5.

[Venous drainage and innervation of the maxillary sinus]

The maxillary sinus, or "Highmore's antrum", is a cavity of the facial structure buried in the body of the maxillary body joined to the nasal fossae with which it communicates via the maxillary ostium. The dissection of 25 maxillary sinuses has enabled us to study its venous drainage and innervation. The venous system is collected either by a single trunk, which is a continuation of the spheno-palatine vein, or by three venous plexus: the anterior and posterior pterygoid plexus, and the alveolar plexus. The anterior and posterior pterygoid plexus converge through the lateral pterygoid muscle and connects with the alveolar plexus which drains partly into the maxillary vein and partly into the facial vein. The innervation of the maxillary sinus is ensured by the maxillary nerve (V2): the second branch of the trigeminal nerve and its collateral branches. During the course of its track the maxillary nerve becomes successively the spheno-palatine nerve and the anterior orbital nerve, and gives rise to some collateral branches: the posterior and superior alveolar ramus, the medium and superior alveolar nexus and the anterior and superior alveolar ramus.