Modeling the consequences of tongue surgery on tongue mobility

This paper presents the current achievements of a long term project aiming at predicting and assessing the impact of tongue and mouth floor surgery on tongue mobility. The ultimate objective of this project is the design of a software with which surgeons should be able (1) to design a 3D biomechanical model of the tongue and of the mouth floor that matches the anatomical characteristics of each patient specific oral cavity, (2) to simulate the anatomical changes induced by the surgery and the possible reconstruction, and (3) to quantitatively predict and assess the consequences of these anatomical changes on tongue mobility and speech production after surgery

Use of a biomechanical tongue model to predict the impact of tongue surgery on speech production

This paper presents predictions of the consequences of tongue surgery on speech production. For this purpose, a 3D finite element model of the tongue is used that represents this articulator as a deformable structure in which tongue muscles anatomy is realistically described. Two examples of tongue surgery, which are common in the treatment of cancers of the oral cavity, are modelled, namely a hemiglossectomy and a large resection of the mouth floor. In both cases, three kinds of possible reconstruction are simulated, assuming flaps with different stiffness. Predictions are computed for the cardinal vowels /i, a, u/ in the absence of any compensatory strategy, i.e. with the same motor commands as the one associated with the production of these vowels in non-pathological conditions. The estimated vocal tract area functions and the corresponding formants are compared to the ones obtained under normal condition

Brain activations in speech recovery process after intra-oral surgery: an fMRI study

International audienceThis study aims at describing cortical and subcortical activation patterns associated with functional recovery of speech production after reconstructive mouth surgery. Our ultimate goal is the understanding of how the brain deals with altered relationships between motor commands and auditory/orosensory feedback, and establishes new inter-articulatory coordination to preserve speech communication abilities. A longitudinal sparse-sampling fMRI study involving orofacial, vowel and syllable production tasks on 9 patients and in three different sessions (one week before, one month and three months after surgery) was conducted. Healthy subjects were recorded in parallel. Results show that for patients in the pre-surgery session, activation patterns are in good agreement with the classical speech production network. Crucially, lower activity in sensorimotor control brain areas during orofacial and speech production movements is observed for patients in all sessions. One month after surgery, the superior parietal lobule is more activated for simple vowel production suggesting a strong involvement of a multimodal integration process to compensate for loss of tongue motor control. Altogether, these results indicate both altered and adaptive sensorimotor control mechanisms in these patients. Index Terms: Neurophonetics, fMRI, speech recovery, motor control, glossectomy, whole-brain analysis, sparse-sampling

Evolution des activations cérébrales lors de la production de parole après exérèse au niveau de la cavité orale

International audienceUsing functional MRI, acoustic data and motor oral assessment, brain correlates of speech recovery after dramatic structural changes in the vocal tract have been investigated during three tasks: orofacial movements and speech production (vowels and syllables). Eleven patients were recorded during three sessions, preoperatively and postoperatively, 1 month and 3 months after surgery (for seven of them also 9 months after surgery). Eleven healthy subjects were recorded in parallel. A "whole brain" group analysis (patients/healthy subjects) reveals a specific activation pattern for patients, in particular during vowel task, which is session-dependent. Moreover, global lower brain activation compared to healthy subjects was found for all tasks in primary, secondary and integrative sensorimotor regions. Differences are interpreted in relation with the emergence of new speech motor goals and changes in the internal models.A partir de données d'IRM fonctionnelle, acoustiques et praxiques, nous avons étudié les corrélats cérébraux de l'adaptation de la parole après une modification structurelle importante du conduit vocal lors de trois tâches : mouvements oro-faciaux silencieux, voyelles et syllabes. Onze patients ont été enregistrés lors de trois sessions, pré-opératoire et post-opératoire à 1 mois et 3 mois (pour sept d'entre eux aussi à 9 mois). Onze sujets contrôles ont été enregistrés en parallèle. Une analyse de groupe (patients/contrôles) " cerveau entier " révèle des patrons d'activation spécifiques aux patients au cours des différentes sessions en particulier pour la tâche de production de voyelles. De plus, une moindre activation cérébrale par rapport aux sujets sains a été observée pour toutes les tâches dans des régions motrices, sensorielles et d'intégration sensori-motrice. Nous interprétons ces résultats en relation avec la redéfinition des buts de parole et l'adaptation de modèles internes du système moteur périphérique

La reconstruction de la cavité buccale (microchirurgie et perspectives en microdialyse)

BESANCON-BU Médecine pharmacie (250562102) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF

Hémangiopéryctome - tumeur fibreuse solitaire maxillaire : à propos d’un cas

Introduction : La tumeur fibreuse solitaire (TFS) est une tumeur rare. Elle appartient à un groupe de lésions comportant de nombreux diagnostics différentiels. Par l'étude d'un cas, les auteurs souhaitent préciser les données cliniques, paracliniques et anatomopathologiques des TFS. Observation : Nous rapportons le cas d’une patiente, suivie depuis 1982 pour un hémangiopéricytome cérébral opéré à plusieurs reprises, adressée dans le service pour exophtalmie avec perte de l’acuité visuelle. Le CT-scan du massif facial retrouvait une récidive dans le maxillaire gauche, avec un envahissement de l'orbite homolatérale. L'artériographie préopératoire permettait d’en préciser la vascularisation et d’emboliser les branches de la carotide externe, et à minima celles de l'artère ophtalmique. La patiente a bénéficié d'une exérèse tumorale avec exentération de l’œil gauche. L'examen anatomopathologique a montré un profil morphologique et immunohistochimique (CD34, bcl-2, CD99) typique d’une TFS avec des signes d’agressivité histologique. Discussion : Pour ce type de tumeur, c'est l'examen anatomopathologique et immunohistochimique qui apporte le diagnostic de certitude. Il existe des critères histologiques corrélés avec un potentiel de récidive locale. L’analyse microscopique permet de déterminer le potentiel agressif de la lésion. L'embolisation de la lésion a facilité l’intervention en diminuant le risque hémorragique. Des évolutions métastatiques sont rapportées dans la littérature. Les TFS nécessitent une exérèse complète pour diminuer le risque de récidive et nécessitent une surveillance prolongée à long terme

Nevus of Ota with palatal involvement: a case report

Nevus of Ota is a macular discoloration of the face which is most commonly found in the Japanese and females are more commonly affected than males. It is first described by Ota and Tanino in 1939, involves the skin along the distribution of first and second division of trigeminal nerve. Involvement of the palatal mucosa occurs rarely in nevus of Ota, it usually blends with the oral mucosa and is typically irregular, undefined and often present as a mottled patch. We describe here the case of nevus of Ota with palatal involvement in a 13-year-old Asiatic boy. His past medical history revealed the presence of the lesion since birth. There were no other pigmented lesion locations. The exact etiology of nevus of Ota is still unknown but they have the potential to undergo melanomatous change

Towards a three-dimensional software model of the oral cavity for tongue surgery planning

International audienceThis work introduces the contribution of a biomechanical model of the oral cavity in the planning of tongue resection surgeries. For this, we exploit a 3D biomechanical model of the tongue (finite element modelling), in which major tongue muscles, either extrinsic or extrinsic, are represented implemented. This model is inserted in the oral cavity including jaw, palate, pharyngeal walls, as well as the hyoid bone. Two common tongue excisions with reconstruction are modelled: a hemiglossectomy and an enlarged mouth floor resection. The impact of the flap mechanical properties on tongue mobility and the production of vowels \i, a, u\ are evaluated in theabsence of any compensatory strategy