O presente estudo buscou investigar o impacto da psicoterapia breve pais-bebê nas representações maternas a respeito de si mesma, sobre o bebê, sobre a relação mãe-bebê, quando o bebê apresenta uma malformação. Participou deste estudo uma família cujo bebê de 11 meses apresentava malformação cardíaca grave, compatível com a vida. Foi utilizado um delineamento de estudo de caso único, sendo que as representações maternas foram examinadas ao longo dos cinco encontros de avaliação inicial, durante as 17 sessões de psicoterapia e num encontro pós-psicoterapia. Todas as verbalizações e interações da mãe com o bebê e com os familiares foram registradas em áudio e vídeo e, posteriormente, analisadas a partir dos quatro temas da constelação da maternidade (Stern, 1997): vida e crescimento, relacionar-se primário, matriz de apoio e reorganização da identidade, que precisaram ser ampliados para atender as particularidades do contexto de malformação. Os resultados apontaram para uma evolução das representações maternas ao longo da psicoterapia, que permitiu à mãe expressar seus sentimentos frente à malformação e reviver alguns de seus conflitos mais primitivos. A visão sobre o bebê passou de mais parcial e idealizada para mais integrada, revelando um potencial de evolução e vulnerabilidade, ao mesmo tempo. A relação mãe-bebê ficou mais próxima, na medida em que a mãe pôde tolerar mais a dependência do bebê e a sua necessidade de cuidados especiais, sem se sentir tão incompetente e culpada. Houve um evidente reforço na rede de apoio da mãe, que se aproximou de sua família de origem e passou a se sentir mais apoiada e compreendida pelo marido. Por fim, a mãe pareceu se apropriar mais do papel materno, porém ainda muito ligada a uma identidade de filha. Apesar de uma redução expressiva nos escores do BDI antes e depois da psicoterapia (31 para 11 pontos), a instabilidade psíquica da mãe e sua fragilidade permaneceram muito fortes, mesmo ao final da psicoterapia, o que sugeriu um prognóstico reservado e a necessidade de indicação de um tratamento mais sistemático, especialmente tendo em vista que a malformação da criança continuava afetando profundamente a vida da família. / The present study aimed to investigate the impact of a brief parent-infant psychotherapy on the maternal representations concerning herself, about the baby, e about the mother-baby relationship, in a situation where the infant had malformation. A family whose baby was 11 months and presented serious heart malformation, compatible with life, took part in the study. A case-study design was used, and maternal representations were examined during five sessions of initial evaluation, of a total of 17 psychotherapy sessions and in a postpsychotherapy session. All the verbalizations and mother's interactions with the baby and with the relatives were registered in audio and video and were later analyzed based on the four themes of the motherhood constellation (Stern, 1997): life and growth, primary relationship, support matrix and reorganization of identity. They all needed to be adapted so as to take into account the particularities of the malformation context. he results showed an evolution of the maternal representations during the psychotherapy, which allowed the mother to express her feelings regarding malformation and to re-experience some of her more primitive conflicts. She changed from a more partial and idealized to a more integrated view of the baby, revealing potential evolution and vulnerability, at the same time. The mother-baby relationship got closer, as the mother could tolerate more the baby's dependence and his need for special care, without feeling so incompetent and guilty. The mother's social support was clearly reinforced, which led her to get closer to her family of origin and to feel more supported and understood by the husband. Finally, the mother seemed to gradually assume the maternal role, even though it was still very tied to her identity as daughter. In spite of an expressive reduction in the scores of BDI after the psychotherapy (31 to 11 points), the mother's psychic instability and her fragility remained very strong, even at the end of the psychotherapy, suggesting a reserved prognostic and the need for indication of a more systematic treatment, especially in view of the child's malformation which continued to deeply affect the family’s life.

O presente estudo buscou investigar o impacto da psicoterapia breve pais-bebê nas representações maternas a respeito de si mesma, sobre o bebê, sobre a relação mãe-bebê, quando o bebê apresenta uma malformação. Participou deste estudo uma família cujo bebê de 11 meses apresentava malformação cardíaca grave, compatível com a vida. Foi utilizado um delineamento de estudo de caso único, sendo que as representações maternas foram examinadas ao longo dos cinco encontros de avaliação inicial, durante as 17 sessões de psicoterapia e num encontro pós-psicoterapia. Todas as verbalizações e interações da mãe com o bebê e com os familiares foram registradas em áudio e vídeo e, posteriormente, analisadas a partir dos quatro temas da constelação da maternidade (Stern, 1997): vida e crescimento, relacionar-se primário, matriz de apoio e reorganização da identidade, que precisaram ser ampliados para atender as particularidades do contexto de malformação. Os resultados apontaram para uma evolução das representações maternas ao longo da psicoterapia, que permitiu à mãe expressar seus sentimentos frente à malformação e reviver alguns de seus conflitos mais primitivos. A visão sobre o bebê passou de mais parcial e idealizada para mais integrada, revelando um potencial de evolução e vulnerabilidade, ao mesmo tempo. A relação mãe-bebê ficou mais próxima, na medida em que a mãe pôde tolerar mais a dependência do bebê e a sua necessidade de cuidados especiais, sem se sentir tão incompetente e culpada. Houve um evidente reforço na rede de apoio da mãe, que se aproximou de sua família de origem e passou a se sentir mais apoiada e compreendida pelo marido. Por fim, a mãe pareceu se apropriar mais do papel materno, porém ainda muito ligada a uma identidade de filha. Apesar de uma redução expressiva nos escores do BDI antes e depois da psicoterapia (31 para 11 pontos), a instabilidade psíquica da mãe e sua fragilidade permaneceram muito fortes, mesmo ao final da psicoterapia, o que sugeriu um prognóstico reservado e a necessidade de indicação de um tratamento mais sistemático, especialmente tendo em vista que a malformação da criança continuava afetando profundamente a vida da família. / The present study aimed to investigate the impact of a brief parent-infant psychotherapy on the maternal representations concerning herself, about the baby, e about the mother-baby relationship, in a situation where the infant had malformation. A family whose baby was 11 months and presented serious heart malformation, compatible with life, took part in the study. A case-study design was used, and maternal representations were examined during five sessions of initial evaluation, of a total of 17 psychotherapy sessions and in a postpsychotherapy session. All the verbalizations and mother's interactions with the baby and with the relatives were registered in audio and video and were later analyzed based on the four themes of the motherhood constellation (Stern, 1997): life and growth, primary relationship, support matrix and reorganization of identity. They all needed to be adapted so as to take into account the particularities of the malformation context. he results showed an evolution of the maternal representations during the psychotherapy, which allowed the mother to express her feelings regarding malformation and to re-experience some of her more primitive conflicts. She changed from a more partial and idealized to a more integrated view of the baby, revealing potential evolution and vulnerability, at the same time. The mother-baby relationship got closer, as the mother could tolerate more the baby's dependence and his need for special care, without feeling so incompetent and guilty. The mother's social support was clearly reinforced, which led her to get closer to her family of origin and to feel more supported and understood by the husband. Finally, the mother seemed to gradually assume the maternal role, even though it was still very tied to her identity as daughter. In spite of an expressive reduction in the scores of BDI after the psychotherapy (31 to 11 points), the mother's psychic instability and her fragility remained very strong, even at the end of the psychotherapy, suggesting a reserved prognostic and the need for indication of a more systematic treatment, especially in view of the child's malformation which continued to deeply affect the family’s life.

Les agents d'embolisation liquides utilisés dans le traitement endovasculaire ont de nombreuses limitations. Des polymères, tels que l’Onyx et les cyanoacrylates sont disponibles. L’alcool est un agent puissant, mais non radio-opaque. Les cyanoacrylates entrainent une réaction inflammatoire significative. Leur polymérisation rapide est responsable d’un comportement mal prévisible.Il existe une possibilité de traitement incomplet.L’Onyx est efficace pour le traitement des MAV.Une pénétration plus distale est obtenue avec l’alcool, mais associée à un risque de migration systémique. Nous avons évalué les propriétés d'un nouvel agent embolique (Alconyx) composé d'un mélange d'alcool et d'Onyx. Cet agent devrait cumuler les avantages respectifs de l'alcool et de l'onyx avec une visualisation adéquate sous fluoroscopie, une meilleure pénétration distale que l'Onyx seul et moins de toxicité systémique liée à la réduction de quantité d’alcool injecté. Divers mélanges ont été testés avec différentes concentrations d'Onyx 18 et d’alcool absolu. Alconyx 25 (75% Onyx 18; 25% d'éthanol) est la formulation la plus prometteuse. Nous avons démontré sa facilité d'injection in vivo, sa nature cohésive sans fragmentation ainsi que sa bonne visualisation sous fluoroscopie. En raison de sa moindre viscosité démontrée in vitro, Alconyx a été capable de pénétrer profondément dans le lit artériel.. L'occlusion proximale par Alconyx 25 devrait permettre d'améliorer le contact entre l'éthanol et la paroi vasculaire et donc augmenter son pouvoir sclérosant et limiter son passage systémique. Les propriétés occlusives d’Alconyx 25 sont similaires à celle de l’Onyx 18 sous haute pression in vitro. / Commercially available liquid embolization agents used in endovascular treatment have many limitations. Polymeric agents as Onyx and cyanoacrylate are available. Ethanol also is a potent sclero-embolic agent. Cyanoacrylates are effective liquid embolic agents, however, their rapid polymerization makes their behaviour unpredictable with possibility of incomplete treatment. These properties render their use challenging.Onyx is easy to use. However, in very small arterial niduses, Onyx, is unable to penetrate deeply. Deep penetration is obtained with ethanol, associated with risk of systemic migration.Poor visualization of ethanol under fluoroscopy is major drawback. Mixing Onyx with ethanol had never been described in the literature till now. In this work, various mixtures have been tested with different concentrations of Onyx 18 and absolute ethanol. Alconyx 25 (75% Onyx 18; 25% ethanol) seems to be a promising product. We proved its ease of injection in vivo and in vitro, its cohesive nature showing no fragmentation or interruption of the injected column as well as its good visualization under fluoroscopy. It was able to penetrate deeply in the arterial bed. The occlusive properties of Alconyx 25 were rated as good as Onyx 18 under high pressure in vitro. Further investigation is needed to better understand the behavior of ethanol in the suspension and its effect on tissues compared to Onyx diluted simply with an equivalent amount of DMSO. Studies on other commercially available concentrations of Onyx would certainly be interesting.

Les malformations du développement cortical (MDC) résultent d’altérations au niveau de différentes étapes de la corticogénèse telles que la prolifération, la migration et la différenciation neuronale et sont généralement associées à des épilepsies pharmaco-résistantes et à des déficiences intellectuelles sévères. Les causes génétiques des MDC restent encore inconnues dans de nombreux cas, nous avons donc réalisé le séquençage de l’exome entier de nombreux patients présentant des MDC et les analyses ont permis de mettre en évidence l’implication des gènes KIF2A et NEDD4L dans les MDC. Dans le cadre de ma thèse, nous proposons de focaliser sur les conséquences cellulaires et neurodéveloppementales résultant des mutations dans les gènes KIF2A et NEDD4L retrouvées chez les patients atteints de MDC. KIF2A code pour une kinésine-13 qui a pour fonction de réguler la dynamique des microtubules (MT) via son activité MT dépolymérase ATP-dépendante aux niveaux des extrémités des MT. L’approche basée sur la technique d’électroporation in utero nous a permis de mettre en évidence le rôle crucial joué par KIF2A dans la régulation de la neurogénèse, la migration neuronale et le positionnement des neurones dans le cortex. En particulier, nos données révèlent que l’expression des mutants KIF2A responsables de MDC entraîne une augmentation du nombre de cellules à l’état de progéniteurs qui est conséquente à un allongement du temps passé dans le cycle cellulaire. Nos premières données cellulaires et au cours du développement montrent que l’expression des mutants KIF2A induit des altérations dans l’intégrité du fuseau mitotique, dans la progression mitotique et également une localisation anormale de KIF2A au niveau du cil primaire. NEDD4L code pour une E3 ubiquitine ligase qui joue un rôle dans l’ubiquitination de nombreux substrats permettant la régulation de leur dégradation et de leur localisation subcellulaire. Dans un premier temps, nos données cellulaires ont montré que les mutants associées à des MDC ont une sensibilité accrue pour la dégradation par le protéasome. De plus, l’approche d’électroporation in utero a permis de montrer que l’expression des mutants NEDD4L ainsi qu’un excès de NEDD4L WT dérégulent la neurogenèse, le positionnement des neurones et le processus de translocation terminal. Des études complémentaires, incluant le traitement à la rapamycine, ont révélé qu’un excès de NEDD4L WT mène à la dérégulation des voies de signalisations mTORC1 et Dab1 tandis que l’expression des mutants est associée à une dérégulation des voies mTORC1 et Akt. L’ensemble de ces résultats renforce donc dans un premier temps l’importance des protéines liées aux MT dans le développement cortical en décrivant le rôle crucial de la kinésine KIF2A dans des mécanismes tels que la dynamique de migration neuronale et dans la régulation du cycle cellulaire des progéniteurs neuronaux. D’autre part, nous fournissons également de nouvelles données permettant de mieux comprendre le rôle critique de NEDD4L dans la régulation des voies mTOR et de leurs contributions dans le développement cortical. / Malformations of cortical development (MCD) result from alterations in different stages of corticogenesis such as proliferation, migration and neuronal differentiation, and are generally associated with drug-resistant epilepsy and severe intellectual disabilities. The genetics causes of MCD remain largely unknown, we have thus performed the whole-exome sequencing of many patients with MCD and reported the identification of multiple pathogenic missense mutations in KIF2A and NEDD4L genes. Within the frame of my thesis project, we propose to focus on the cellular and neurodevelopmental consequences resulting from KIF2A and NEDD4L mutations shown to be involved in MCD. KIF2A is a member of the kinesin-13 family, which rather than regulating cargos transport along microtubules (MT), regulates MT dynamics by depolymerizing MTs. The in utero electroporation approach allowed us to highlight the crucial role of KIF2A in the regulation neurogenesis, neuronal migration and the neuronal positioning in the cortex. Particularly, our data show that the expression of the KIF2A mutants involved in MDC lead to an increase in the number of cells in proliferative state which is a consequence of a prolonged time spent in the cell cycle. Our first cellular data and during development show that the expression of pathogenic KIF2A mutations induce alterations in the mitotic spindle integrity, in the mitotic progression and also an abnormal localization of KIF2A in the primary cilium. NEDD4L encodes a member of the NEDD4 family of HECT-type E3 ubiquitin ligases known to regulate the turnover and function of a number of proteins involved in fundamental cellular pathways and processes. Firstly, cellular and expression data showed sensitivity of MCD-associated mutants to proteasome degradation. Moreover, the in utero electroporation approach showed that PNH-related mutants and excess wild-type NEDD4L affect neurogenesis, neuronal positioning and terminal translocation. Further investigations, including rapamycin-based experiments, found differential deregulation of pathways involved. Excess wild-type NEDD4L leads to disruption of Dab1 and mTORC1 pathways, while MCD-related mutations are associated with deregulation of mTORC1 and AKT activities. Altogether, these results reinforce the importance of MT-related proteins in cortical development describing the crucial role of KIF2A kinesin in mechanisms such as neuronal migration dynamics and neuronal progenitor’s cell cycle regulation. On the other hand, we also provide new data to better understand the critical role of NEDD4L in the regulation of mTOR pathways and their contributions in cortical development.

Introdução: O 1º e 2º arcos faríngeos contribuem com o desenvolvimento craniofacial e interferências no seu desenvolvimento podem resultar em alterações de gravidade variável, envolvendo maxila, mandíbula e orelha. Das anomalias associadas à malformação de orelha externa, a hipoplasia mandibular, o dermóide epibulbar e a anomalia de coluna cervical são as mais freqüentes e, este conjunto de sinais tem sido denominado espectro oculoauriculovertebral. O EOAV é uma condição heterogênea e complexa e o espectro de anomalias inclui desde microtia isolada até outras anomalias cranianas e extracranianas. Objetivo: analisar e descrever a morfologia da mandíbula, com ênfase na articulação temporomandibular (ATM) e investigar orelha média e interna em indivíduos com anomalias de 1º e 2º arcos faríngeos cadastrados no Serviço de Genética Clinica do HRAC USP. Indivíduos estudados e métodos: avaliação genética-clínica e avaliação por imagem enfocando orelha média, interna e côndilo mandibular foram realizadas em 56 indivíduos, cadastrados no Serviço de Genética Clínica do Hospital de Reabilitação de Anomalias Craniofaciais USP. O critério mínimo utilizado foi a presença de microtia isolada ou de microssomia hemifacial com malformação auricular leve, como apêndices pré-auriculares. Resultados e conclusão: anomalias envolvendo côndilo mandibular e/ou mandíbula e anomalias de orelha média mostraram alta freqüência (87.5% e 96.1%, respectivamente) nos indivíduos da presente casuística. Relação preditiva entre a ocorrência e a gravidade das anomalias de côndilo mandibular e/ou mandíbula com o acometimento da orelha externa e, relação preditiva para a ocorrência do acometimento do côndilo mandibular com a ocorrência de anomalias estruturais de orelha média e orelha interna foram observadas. Para a avaliação da ATM, a tomografia computadorizada foi considerada o exame de eleição. A investigação das estruturas do côndilo mandibular, da orelha média e interna deve fazer parte do protocolo de avaliação dos indivíduos com anomalias de 1º e 2º arcos faríngeos. / Introduction: The first and second pharingeal arches contribute to craniofacial development and interferences in normal development of these structures can result in maxillary, mandibular, and ear abnormalities. Mandible hypoplasia, epibulbar dermoids, and spinal vertebral defects are the most frequent anomalies combined with ear anomalies and this group has been called oculoauriculovertebral spectrum. This is a heterogeneous and complex condition that includes isolated microtia until other cranial and extracranial anomalies. Purpose: To analyze and describe the morphology of the mandible, with special approach to the temporomandibular joint and to investigate the middle and inner ear in patients with first and second pharyngeal arches involvement. Methods: Clinical genetics evaluation, radiological and CT scan evaluation with main focus in middle and inner ear structures as well as in mandible. This study was performed in fifty six patients at the Hospital of the Rehabilitation of the craniofacial anomalies USP. Minimal diagnostic criteria were the presence of preauricular tags or mild external ear anomaly associated to facial asymmetry. Results and Conclusions: Condyle and/or mandible and middle ear anomalies showed high frequency (87.5% and 96.1%) for the patients of the present study. Predictive relation between the occurrence and the gravity for condyle anomalies and/or mandible with involvement of the external ear was observed. Other predictive relation was observed between the occurrence of condyle anomalies with involvement of structural anomalies of middle and inner ear. CT scan proved to be the most appropriated tool for temporomandibular joint evaluation. Evaluation of condyle structures, middle and inner ear should be included in protocols for evaluation of conditions with first and second pharingeal arches involvement.

La migration radiaire est un des processus clefs de la corticogenèse menant à l’établissement d’un cortex en six couches chez les mammifères. La compréhension de ce mécanisme complexe est nécessaire à une meilleure appréhension du développement cortical. Dans ce travail de thèse, j’ai étudié la migration des neurones pyramidaux du cortex sous deux angles distincts. La 1ère partie se place d’un point de vue développemental en appréciant comment le positionnement laminaire résultant d’une migration normale ou anormale affecte la maturation neuronale. La 2nde partie se concentre sur une pathologie migratoire, l’hétérotopie en bande sous-corticale, et les altérations cognitives parfois associées à cette malformation. Pour ces deux projets, la migration neuronale a été altérée chez le rat par knockdown (KD) in utero de la doublecortine (Dcx), un effecteur majeur de la migration. Les neurones positionnés anormalement présentent une orientation incorrecte, un arbre dendritique moins développé, une spinogenère réduite et une altération morpho-fonctionnelle de la synaptogenèse glutamatergique. De plus, notre étude a mis en évidence l’implication de Dcx dans la dendritogenèse et la régulation fine des synapses glutamatergiques in vivo. Enfin, nous avons utilisé les rats Dcx-KD comme modèle d’hétérotopie en bande afin d’étudier comment un déficit de migration neuronale impacte le fonctionnement du cortex. La caractérisation comportementale, réalisée à l’aide d’une large gamme de tests, n’a pas mis en évidence de déficits majeurs des capacités motrices, somatosensorielles ou cognitives chez ces animaux. / Radial migration is one of the key processes leading to the formation of a six-layered cortex in mammals. Understanding this mechanism is necessary to get a better grasp of cortical development. During my PhD, I studied neuronal migration of pyramidal neurons from two different points of views. The 1st part is related to fundamental biology and assesses how laminar misplacement resulting from migration failure influences neuronal maturation. The 2nd one focuses on pathology by investigating a migration disorder, subcortical band heterotopia, and associated cognitive deficits. For both projects, neuronal migration was impaired in rat through in utero knockdown (KD) of doublecortin (Dcx), a major effector of cortical migration. Misplaced neurons display an abnormal orientation, a simplified dendritic arbor, a decreased spinogenesis and morpho-functional alterations of glutamatergic synaptogenesis. Moreover, our study shows that Dcx plays a role in dendritogenesis, in shaping spine morphology and in fine-tuning glutamatergic synaptogenesis. Finally, we used Dcx-KD rats as an animal model of subcortical band heterotopia to assess how migration failure would impact cortical functions. The behavioral characterization carried out through a wide range of tests did not bring to light any major shortcoming regarding motor, somatosensory or cognitive abilities in these animals. Therefore, although Dcx-KD rats display a SBH and develop spontaneous seizures, it does not seem to recapitulate cognitive deficits found in patients.

Introdução: O 1º e 2º arcos faríngeos contribuem com o desenvolvimento craniofacial e interferências no seu desenvolvimento podem resultar em alterações de gravidade variável, envolvendo maxila, mandíbula e orelha. Das anomalias associadas à malformação de orelha externa, a hipoplasia mandibular, o dermóide epibulbar e a anomalia de coluna cervical são as mais freqüentes e, este conjunto de sinais tem sido denominado espectro oculoauriculovertebral. O EOAV é uma condição heterogênea e complexa e o espectro de anomalias inclui desde microtia isolada até outras anomalias cranianas e extracranianas. Objetivo: analisar e descrever a morfologia da mandíbula, com ênfase na articulação temporomandibular (ATM) e investigar orelha média e interna em indivíduos com anomalias de 1º e 2º arcos faríngeos cadastrados no Serviço de Genética Clinica do HRAC USP. Indivíduos estudados e métodos: avaliação genética-clínica e avaliação por imagem enfocando orelha média, interna e côndilo mandibular foram realizadas em 56 indivíduos, cadastrados no Serviço de Genética Clínica do Hospital de Reabilitação de Anomalias Craniofaciais USP. O critério mínimo utilizado foi a presença de microtia isolada ou de microssomia hemifacial com malformação auricular leve, como apêndices pré-auriculares. Resultados e conclusão: anomalias envolvendo côndilo mandibular e/ou mandíbula e anomalias de orelha média mostraram alta freqüência (87.5% e 96.1%, respectivamente) nos indivíduos da presente casuística. Relação preditiva entre a ocorrência e a gravidade das anomalias de côndilo mandibular e/ou mandíbula com o acometimento da orelha externa e, relação preditiva para a ocorrência do acometimento do côndilo mandibular com a ocorrência de anomalias estruturais de orelha média e orelha interna foram observadas. Para a avaliação da ATM, a tomografia computadorizada foi considerada o exame de eleição. A investigação das estruturas do côndilo mandibular, da orelha média e interna deve fazer parte do protocolo de avaliação dos indivíduos com anomalias de 1º e 2º arcos faríngeos. / Introduction: The first and second pharingeal arches contribute to craniofacial development and interferences in normal development of these structures can result in maxillary, mandibular, and ear abnormalities. Mandible hypoplasia, epibulbar dermoids, and spinal vertebral defects are the most frequent anomalies combined with ear anomalies and this group has been called oculoauriculovertebral spectrum. This is a heterogeneous and complex condition that includes isolated microtia until other cranial and extracranial anomalies. Purpose: To analyze and describe the morphology of the mandible, with special approach to the temporomandibular joint and to investigate the middle and inner ear in patients with first and second pharyngeal arches involvement. Methods: Clinical genetics evaluation, radiological and CT scan evaluation with main focus in middle and inner ear structures as well as in mandible. This study was performed in fifty six patients at the Hospital of the Rehabilitation of the craniofacial anomalies USP. Minimal diagnostic criteria were the presence of preauricular tags or mild external ear anomaly associated to facial asymmetry. Results and Conclusions: Condyle and/or mandible and middle ear anomalies showed high frequency (87.5% and 96.1%) for the patients of the present study. Predictive relation between the occurrence and the gravity for condyle anomalies and/or mandible with involvement of the external ear was observed. Other predictive relation was observed between the occurrence of condyle anomalies with involvement of structural anomalies of middle and inner ear. CT scan proved to be the most appropriated tool for temporomandibular joint evaluation. Evaluation of condyle structures, middle and inner ear should be included in protocols for evaluation of conditions with first and second pharingeal arches involvement.

Les malformations artérioveineuses (MAV) cérébrales sont une pathologie rare et hétérogène dont l’imagerie est complexe du fait de leur caractère dynamique et la prise en charge controversée notamment du fait des risques liés aux traitements proposés.La première partie de cette thèse porte sur l’imagerie des MAVs, axée sur une nouvelle technique, l’angiographie en 4 dimensions. Initialement, nous avons étudié sa faisabilité et validé cette technique en la comparant à l’angiographie cérébrale conventionnelle. Puis nous l’avons comparé à une autre modalité dynamique, l’angiographie par résonance magnétique en 4 dimensions, dans l’analyse des caractéristiques angio-architecturales des MAVs. Enfin, nous avons utilisé cette technique comme aide au planning pré et peropératoire dans la chirurgie des micro-MAVs.La seconde partie de cette thèse porte sur la prise en charge des patients porteurs d’une MAV dans le cadre d’études cliniques. Face à l’absence de consensus et aux hétérogénéités des pratiques sur la prise en charge de cette pathologie, la réflexion de ce travail a été conduite en plusieurs temps : un état des lieux basé sur une revue systématique des critiques faites à un essai randomisé sur les MAVs non rompues ; puis la conception d’une nouvelle étude pragmatique en soins courant, randomisée et intégrant le jugement clinique du praticien et de l’équipe multidisciplinaire ; l’évaluation de l’applicabilité de cette conception aux différentes pratiques via l’interrogation des praticiens par questionnaires ; la mise en place de cette étude multicentrique internationale TOBAS (Treatment of Brain Arteriovenous Malformation) ; et enfin, l’analyse des résultats de la phase pilote montrant la faisabilité de l’étude. / Brain arteriovenous malformations (AVMs) are a rare and heterogeneous pathology. Imaging anAVM is complex because of their temporal dynamic feature. The management is controversial in particular due to the risks associated with the proposed treatments.The first part of this work is about imaging AVMs. We focused on a new technique, 4-Dimensional digital substraction angiography (4D DSA). Initially, we studied its feasibility and validated this technique in comparison with conventional cerebral angiography. Then we compared 4D DSA with another dynamic modality, 4-dimensional magnetic resonance angiography (4D MRA), in the analysis of angio-architectural characteristics of AVMs. Finally, we used this technique as a supplementary tool in the pre- and intraoperative planning of micro-AVM surgery.The second part deals with the management of AVMs patients in clinical studies. Given the lack of consensus, and the heterogeneity of practices in the management of this pathology, the conduct of this work was done in several stages: a systematic review and a critical analysis of a randomized trial recently published on unruptured brain AVMs; the design of a new pragmatic randomized trial incorporating the clinical judgment of the multidisciplinary team, the evaluation of the applicability of this design to the different practices using questionnaires; the implementation of this international multi-center study called TOBAS (Treatment of Brain Arteriovenous Malformation); and finally, the analysis of the pilot phase of the study.

La malformation anévrysmale de la veine de Galien (MAVG) est une malformation vasculaire cérébrale congénitale qui représente près d’un tiers des anomalies vasculaires pédiatriques. Au sein d’une cohorte de 51 patients atteints d’une MAVG, nous avons identifié 5 individus porteurs de mutations hétérozygotes pathogéniques d’EPHB4. Ces mutations incluent une mutation tronquante survenue de novo ainsi que des mutations d’épissage et faux-sens hétérozygotes délétères héritées d’un parent. L’invalidation d’EPHB4 chez les embryons de Danio rerio est à l’origine d’anomalies vasculaires cérébrales spécifiques impliquant la veine dorsale longitudinale, la veine orthologue médiane du prosencéphale (précurseur embryonnaire de la veine de Galien). La co-injection de l’ARNm tronqué a permis la restauration d’un phénotype sauvage démontrant que le phénotype vasculaire observé est la conséquence d’une perte de fonction d’EPHB4. L’ensemble de ces données indique qu’EPHB4 est un gène déterminant chez un sous-groupe de patients atteints d’une MAVG, comme chez Danio rerio. Les mutations perte de fonction d’EPHB4 sont à l’origine d’anomalies spécifiques du développement vasculaire cérébral. L’identification de mutations pathogéniques d’EPHB4 chez des patients présentant des malformations capillaires implique une surveillance attentive de la grossesse. Cette surveillance échographique renforcée pourrait permettre la détection précoce d’une MAVG et une prise en charge anténatale et néonatale optimale. / Vein of Galen aneurysmal malformation (VGAM) is one of the most common fetal brain vascular malformations. We conducted whole exome sequencing in 19 unrelated VGAM patients and subsequently screened candidate gene in a cohort of 32 additional patients. We found 5 affected individuals with heterozygous mutations in EPHB4 including de novo frameshift or inherited deleterious splice or missense mutations predicted to be pathogenic by in silico tools. Knockdown of EPHB4 in zebrafish embryos leads to specific anomalies of dorsal cranial vessels including dorsal longitudinal vein, the ortholog of the median prosencephalic vein, the embryonic precursor of the vein of Galen. This model allowed todemonstrate EPHB4 loss of function mutations in VGAM by the ability to rescue the brain vascular defect in knockdown zebrafish co-injected with wild type but not truncated EPHB4 mimicking the frameshift mutation. Our data showed that in both species, loss of function mutations of EPHB4 result in specific and similar brain vascular development anomaliesThe identification of EPHB4 pathogenic mutation in patients presenting capillary malformation or VGAM should lead to careful follow up of pregnancy of carriers for early detection of VGAM in order to propose optimal neonatal care. Endovascular embolization indeed greatly improved the prognosis of VGAM patients.

No description available.