28 research outputs found

    [What is Piezosurgery? Two-years experience in craniomaxillofacial surgery]

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    International audienceINTRODUCTION: Piezosurgery is a new surgical technique used in dentistry to section hard tissues without damaging adjacent soft tissues. We hypothesized that such a device could also be useful in craniofacial and orthognathic surgery. MATERIAL AND METHOD: An ultrasonic device (Mectron) was employed in different craniofacial surgical procedures: a) to perform 144 Le Fort I osteotomies, 140 palatal expansions after Le Fort I osteotomies, and 134 bilateral sagittal osteotomies; b) to perform a Le Fort III osteotomy for treatment of Crouzon syndrome in 2 patients; c) to perform 5 segmental osteotomies and 3 osteotomies of the inferior edge of the mandible for facial asymmetry; d) to perform 12 cases of unicortical calvarial bone grafting; e) to remove the superior orbital roof in 20 cases of craniofaciostenosis and the frontal bone in 5 cases; f) to remove the external wall of the orbit or the anterior and posterior wall of the frontal sinuses in 10 cases of orbital cavity tumors; g) to approach the skull base through the frontal sinuses in 4 cases. Integrity of soft tissues and surgical time were evaluated. RESULTS: Analysis of the results showed that Piezosurgery: a) allows very precise cutting; b) avoids bone cutting using an osteotome; c) spares soft tissue such as brain, dura-mater, palatal mucosa, and the inferior alveolar nerve; d) increases the time of bone cutting but not the overall operative time because of the absence of soft tissue protection. DISCUSSION: Piezosurgery is a new technical procedure, which can be advantageous for bone cutting in many situations, sparing adjacent soft tissues such as brain, palatal mucosa, and the inferior alveolar nerve from any damage. The device's lack of power appears to be a minor problem compared with the advantages

    Utilisation du derme dorsal autologue en reconstruction lamellaire palpébrale postérieure en blépharopoïèse

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    International audienceObjectivesBlepharopoiesis represents a double aesthetic and functional challenge. If anterior lamellar reconstruction is less discussed, the variety of posterior lamellar substitutes testifies that none is ideal. We report here our experience of the use of autologous dermal dermis as posterior lamellar substitutes in bilamellar blepharopoiesis.Patients and methodWe performed a single-center retrospective observational study of seven patients undergoing blepharopoiesis using dorsal dermal autograft as posterior lamellar substitute.ResultsBetween September 2011 and January 2017, seven patients aged of 80.9 years on average were cared for. The defect, affecting in 6 cases on 7 the lower eyelid, concerned almost three-quarter of the length of the eyelid. These defects followed the excision of basal cell carcinomas. Procedures performed under local anesthesia have simple follow-up without complications of the donor site. The superficial surface of the graft in contact with eyeball was covered in 2.4 months with a non-keratinized squamous epithelium like the conjunctiva. Two patients presented ocular functional signs during 2 months without keratitis. Two patients required a second correction procedure.ConclusionThe use of the dorsal dermis seems reliable, simple, fast, possible under local anesthesia and sedation, achievable in one operative time, outpatient, without temporary tarsorraphy. The graft is available in large quantities and its removal is not morbid. The good functional and esthetic results suggest that the autologous dermal dermis could represent the main alternative to palatal fibromucosa as a posterior lamellar substitute in old population.ObjectifsLa blépharopoïèse représente un double défi esthétique et fonctionnel. Si la reconstruction lamellaire antérieure est moins discutée, la variété des substituts lamellaires postérieurs témoigne qu’aucun n’est idéal. Nous rapportons ici notre expérience de l’utilisation du derme dorsal autologue comme substitut lamellaire postérieur en blépharopoïèse bilamellaire.Patients et méthodeNous avons réalisé une étude observationnelle rétrospective monocentrique sur sept patients opérés d’une blépharopoïèse utilisant comme substitut lamellaire postérieur une autogreffe dermique dorsale.RésultatsEntre septembre 2011 et janvier 2017, sept patients âgés de 80,9 ans en moyenne ont été pris en charge. Les pertes de substances, touchant dans 6 cas sur 7 la paupière inférieure, concernaient presque trois-quarts de la longueur palpébrale. Ces pertes de substances faisaient suite à l’exérèse de carcinomes basocellulaires. Les interventions, réalisées sous anesthésie locale ont présenté des suites simples sans complications du site donneur. La face superficielle du greffon au contact du globe était couverte en 2,4 mois d’un épithélium malpighien non kératinisé de type conjonctival. Deux patients ont présenté des signes fonctionnels oculaires durant 2 mois sans kératite. Deux patients ont nécessité une reprise à distance.ConclusionL’utilisation du derme dorsal semble fiable, simple, rapide, possible sous anesthésie locale et sédation, réalisable en un temps opératoire, en ambulatoire, sans tarsorraphie provisoire. Le greffon est disponible en grande quantité et son prélèvement est non morbide. Les bons résultats fonctionnels et esthétiques suggèrent que le derme dorsal autologue pourrait représenter l’alternative principale à la fibromuqueuse palatine comme substitut lamellaire postérieur chez les patients âgés fragiles

    Memoire d'informations latentes et systeme de traitement multiprocesseur

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    On présente un système de traitement multiprocesseur développé par le Centre d'Analyse de Systèmes (CAPCA) pour des besoins de traitement du signal en temps réel (dispositif à large bande effectuant de la veille passive). Le but visé est l'obtention d'une puissance de traitement importante et modulaire (puissance équivalente à celle obtenue par quelques dizaines de miniordinateurs) sous un encombrement réduit (3 à 4 baies). Les opérations à exécuter peuvent être répétitives ou quelconques. La structure développée est conçue pour traiter de façon efficace des données délivrées par un analyseur de spectre fonctionnant en temps réel. Elle est également bien adaptée au traitement des images. Le système est organisé autour d'une mémoire d'information latente (MIL) à adressage tridimensionnel paginé à laquelle accèdent des processeurs d'entrée et de sortie, de traitement et de maintenance. Les moyens de traitement utilisés sont : - La machine 1 de THOMSON/DRS mettant en oeuvre les composants de la série 2900, - Un processeur développé par le CAPCA mettant en oeuvre le microprocesseur MOTOROLA 68000, - Un processeur mettant en oeuvre le microprocesseur TEXAS 9900 utilisé dans la phase maquette. On décrit : - Les principes de fonctionnement, - L'organisation système, - Les éléments matériels principaux, - Les logiciels de développement et d'aide à la mise au point, - Les logiciels de test et de localisation d'avarie. On introduit des notions nouvelles et originales concernant la standardisation des bus internes aux processeurs (bus 16 bits standardisé compatible avec les microprocesseurs 16 bits monolithiques), l'architecture des mémoires d'informations latentes, l'utilisation des microprocesseurs MOTOROLA 68000 et TEXAS 9900, la standardisation fonctionnelle des cartes, etc..

    Survival and spread of Shiga toxin-producing Escherichia coli in alpine pasture grasslands

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    International audienceAims: To determine the fate of Shiga toxin-producing Escherichia coli (STEC) strains defecated onto alpine grassland soils. Methods and Results: During the summers of 2005 and 2006, the field survival of STEC was monitored in cowpats and underlying soils in four different alpine pasture units. A most probable number (MPN)-PCR stx assay was used to enumerate STEC populations. STEC levels ranged between 3Æ9 and 5Æ4 log10 CFU g)1 in fresh cowpats and slowly decreased until their complete decay (inactivation rates k < 0Æ04 day)1). PFGE typing of STEC strains isolated from faecal and soil samples assessed the persistence of various clonal types for at least 2 months in cowpats and their vertical dispersal down through the soil at a depth up to at least 20 cm. STEC cells counts in soil were always below 2 log10 CFU g)1, regardless of the pasture unit investigated. The soil became rapidly free of detectable STEC once the cowpat had decomposed. The eight STEC strains isolated during this study belonged to six distinct serotypes and tested positive for the gene(s) stx2, including the stx2g and stx2 NV206 variants. Conclusions: STEC were able to persist in cowpats and disseminate down through the soil but were unable to establish. Significance and impact of the Study: This study provides useful information concerning the ecology of STEC in alpine pasture grasslands and may have implications for land and cattle management

    Purely Endoscopic Keyhole Supraorbital Approaches for Anterior and Middle Skull Base Tumors

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    Anterior and middle skull base tumors, mainly meningiomas, are usually operated on using a sub-frontal route with a microscope. With modern radiotherapy, the goal of skull base surgery moves from a radical surgery with high rate of side effect to a functional concept that aims to remove as much as possible of the tumor without compromising the neurological status of patients. Minimally skull base surgery benefits from keyhole and endoscopy techniques. For 3 2 decades, the development of endoscopy helps to imagine innovative approaches for skull base tumors such as the endonasal route. Nonetheless, CSF leak issue and the absence of direct control of the tumor margins may limit the interest of such a route. Keyhole craniotomies have been developed with microscope but vision issue limits their use. Combining advantages of both techniques appears therefore natural and gave birth to intracranial assisted and more recently to fully endoscopic keyhole surgery. For anterior or middle skull base tumors, Keyhole supraorbital approaches can be done either by a trans-eyebrow or trans-eyelid routes. A step-by-step description of these fully endoscopic alternative routes summarizing advantages and drawbacks compared to others (traditional sub-frontal or more recent endonasal approaches) is reported in this chapter by the authors
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