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Introduction La racine sensitive du nerf trijumeau dans le cavum trigeminal de Meckel est classiquement segmentee en deux parties : le ganglion trigeminal et le plexus triangulaire. Le plexus triangulaire a ete defini comme la portion du nerf trijumeau situee entre la partie posterieure du ganglion trigeminal et le bord superieur de l’arete petreuse. L’anatomie du plexus triangulaire est plutot relativement meconnue dans les dissections anatomiques recentes. Son anatomie morphologique et fonctionnelle a ete revue par les auteurs apres realisation d’une revue de la litterature systematique. Methodes Nous avons realise une revue systematique de l’anatomie du plexus triangulaire selon le modele PRISMA aupres de bases bibliographiques diverses : – avant 1947 : Medic@ Library (BIU Sante Paris, 2017) ; Index-Catalog of the Library of the Surgeon-General's Office (US National Library of Medicine, 2017) ; Gallica (Bibliotheque nationale francaise, 2017) ; – apres 1947 : PUBMED, PubMed Central et MEDLINE. Resultats Parmi 56 articles retenus pour une lecture complete, 23 furent inclus. Le plexus triangulaire est une entite anatomique situee dans le cavum trigeminal avec des particularites anatomiques propres : sa forme triangulaire (30,2 %), sa distribution plexuelle (97,4 %), presentant des anastomoses sensitives, motrices et sympathiques qui respectent cependant la distribution somatotopique du nerf trijumeau (93,3 %). La stimulation electrique directe du plexus triangulaire (durant les thermorhizotomies par radiofrequence) confirme cette somatotopie fonctionnelle malgre la presence d’anastomoses. Conclusion Une comprehension de l’anatomie du plexus triangulaire peut contribuer au succes de la chirurgie de la nevralgie du trijumeau et jouer un role dans la comprehension des pathologies chirurgicales en particulier tumorales du cavum trigeminal.

Introduction Le nerf trijumeau dans le cavum trigeminal est classiquement segmente en deux parties : – le ganglion trigeminal ; – le plexus triangulaire. Il comporte une racine sensitive et une racine motrice. L’anatomie du plexus triangulaire est plutot relativement meconnue dans les dissections anatomiques recentes. Cette revue de la litterature utilisant la terminologie anatomique resume les connaissances actuelles concernant ses descriptions anatomiques et explique ses implications cliniques et chirurgicales. Materiel et methodes Nous avons realise une revue systematique de l’anatomie du plexus triangulaire selon le modele PRISMA aupres de bases bibliographiques diverses. - Avant 1947 : Medic@ Library (BIU Sante Paris, 2017) ; Index-Catalog of the Library of the Surgeon-General's Office (US National Library of Medicine, 2017) ; Gallica (Bibliotheque Nationale Francaise, 2017). Apres 1947 : PUBMED, PubMed Central et MEDLINE. Resultats Le plexus triangulaire est situe dans un prolongement arachnoidien de la citerne de l’angle ponto-cerebelleux, formant la citerne trigeminale du cavum de Meckel. Le plexus triangulaire est une entite anatomique situee dans le cavum trigeminal avec des particularites anatomiques propres : sa forme triangulaire, sa distribution plexuelle siege d’une reorganisation somatotopique faisant suite au ganglion trigeminal. Conclusion Une comprehension de l’anatomie du plexus triangulaire peut contribuer au succes de la chirurgie de la nevralgie du trijumeau et jouer un role dans la comprehension des pathologies chirurgicales en particulier tumorales du cavum trigeminal (schwannome, le kyste dermoide et epidermoide, kyste arachnoidien).

Using the positions of the eyelids is an effective and contact-free way for the measurement of startle induced eye-blinks, which plays an important role in human psychophysiological research. To the best of our knowledge, no methods for an efficient detection and tracking of the exact eyelid contours in image sequences captured at high-speed exist that are conveniently usable by psychophysiological researchers. In this publication a semi-automatic model-based eyelid contour detection and tracking algorithm for the analysis of high-speed video recordings from an eye tracker is presented. As a large number of images have been acquired prior to method development it was important that our technique is able to deal with images that are recorded without any special parametrisation of the eye tracker. The method entails pupil detection, specular reflection removal and makes use of dynamic model adaption. In a proof-of-concept study we could achieve a correct detection rate of 90.6%. With this approach, we provide a feasible method to accurately assess eye-blinks from high-speed video recordings.

Background The anterior clinoid process shares a close relationship with the optic canal, the internal carotid artery, the superior orbital fissure and the cavernous sinus. These structures may be involved in diseases whose surgical exposure requires prior clinoid process resection. Method Based on operative cases we describe the different steps of this surgical technique and illustrate our surgical procedure with a video. Dividing the orbito-temporal periosteal fold is a key-step in order to optimize the elevation of the periosteal dural layer at the level of the superior orbital fissure to expose the contours of the anterior clinoid process. The clinoid tip is removed after “debulking” the bony content inside the anterior clinoid process in order to leave only a thin shell of bony contour. The bony shell is then detached from the dura, twisted and pulled out. The indications and limitations of the technique are presented. Conclusion The extradural approach of the anterior clinoid process totally provides a full resection of the anterior clinoid process and safety for the paraclinoid space structures. Meticulous stepwise bony resection and optimized dura opening contribute to reduce the risk inherent to this technique.

Objective: Centrally active α-1-adrenergic-receptor antagonists such as prazosin are effective in the treatment of nightmares in patients with posttraumatic stress disorder (PTSD). A pharmacological alternative is doxazosin, which has a longer half-life and fewer side effects. However, doxazosin is currently being used without solid empirical evidence. Furthermore, no study so far has assessed the effects of α-1-antagonists on nightmares in patients with borderline personality disorder (BPD). We retrospectively assessed the effectiveness of doxazosin on nightmares in PTSD and BPD. Method: A retrospective chart review of patients treated with doxazosin for trauma-associated nightmares in our clinic was performed. As in previous prazosin studies, the B2 score of the Clinician-Administered PTSD Scale (CAPS) was used as the primary outcome measure. Furthermore, the Pittsburgh Sleep Quality Index-Addendum for PTSD (PSQI-A) and sleep logs were analyzed. Results: We identified 51 patients with PTSD and/or BPD (mean age 35.7 years, 92.3% women) who received doxazosin for nightmares. Of these, 46 patients continued doxazosin over a 4-week period and 31 patients over a 12-week period. Within the 12-week period, doxazosin treatment significantly reduced nightmares regardless of PTSD/BPD. 25 percent of patients treated for 12 weeks had full remission of nightmares. PSQI-A scores indicated that additional trauma-associated sleep symptoms improved over 12 weeks. Furthermore, recuperation of sleep improved with doxazosin within the first 4 weeks of treatment. Conclusion: Doxazosin might improve trauma associated nightmares and more general sleep parameters in patients with PTSD and BPD. Randomized controlled trials are warranted.

Statistical shape models based on point distribution models are powerful tools for image segmentation or shape analysis. The most challenging part in the generation of point distribution models is the identification of corresponding landmarks among all training shapes. Since in general the true correspondences are unknown, correspondences are frequently established under the hypothesis that correct correspondences lead to a compact model, which is mostly tackled by continuous optimisation methods. In favour of the prospect of an efficient optimisation, we present a simplified view of the correspondence problem for statistical shape models that is based on point-set registration, the linear assignment problem and mesh fairing. At first, regularised deformable point-set registration is performed and combined with solving the linear assignment problem to obtain correspondences between shapes on a global scale. With that, rough correspondences are established that may not yet be accurate on a local scale. Then, by using a mesh fairing procedure, consensus of the correspondences on a global and local scale among the entire set of shapes is achieved. We demonstrate that for the generation of statistical shape models of deep brain structures, the proposed approach is preferable over existing population-based methods both in terms of a significantly shorter runtime and in terms of an improved quality of the resulting shape model.

Introduction Le management optimal des fistules durales intracrâniennes demeure controverse. Certains auteurs preconisent un traitement endovasculaire, efficace mais pouvant etre limite par (1) un acces impossible au pied de veine, (2) une embolisation incomplete, (3) une recanalisation. Nous rapportons ici notre experience concernant le traitement microchirurgical apres echec d’embolisation, insistant sur l’importance d’un traitement precoce pour eviter une degradation clinique a long terme. Materiels et methodes Cette etude est retrospective monocentrique a propos de 6 patients ayant subi un traitement chirurgical pour une fistule durale de la base du crâne Cognard grade IV apres une ou plusieurs tentatives d’embolisation entre janvier 2006 et juillet 2016. Resultats Tous les patients ont presente un echec d’embolisation. Le score de Rankin modifie moyen du diagnostic au traitement chirurgical augmente de 1,8 a 2,7. Apres traitement chirurgical, les symptomes ont ete ameliores chez 5 patients (83,3 %), stabilises dans 1 cas. Dans tous les cas, une occlusion chirurgicale complete fut obtenue, sans hemorragie ou recurrence en 5,4 ans de suivi moyen. Conclusion L’occlusion chirurgicale des fistules durales Cognard grade IV obtient d’excellent resultat en termes d’occlusion. Cependant, une occlusion complete n’est pas necessairement synonyme d’amelioration clinique surtout en cas de delai d’occlusion important. Tant que le shunt n’est pas occlus, une risque hemorragique et fonctionnel persiste. Une tentative d’embolisation peut etre envisagee. En cas d’echec, une chirurgie precoce d’exclusion semble etre l’attitude a preconiser.

Introduction La Nevralgie Vago-GlossoPharyngienne (NVGP) est une pathologie rare comparativement aux nevralgies trigeminales. Si la douleur est resistante aux traitements medicaux et qu’un conflit neurovasculaire est suspecte, une decompression microvasculaire peut etre proposee. L’arachnoide pourrait jouer un role physiopathologique parfois. Materiel et methodes Nous reportons deux cas de patients presentant une douleur electrique pharyngienne et auriculaire declenchee par la deglutition. L’IRM preoperatoire retrouve un conflit neurovasculaire dans le premier cas, un kyste arachnoidien dans le second. Une chirurgie par voie retrosigmoidienne fut realisee. Resultats Dans les deux cas, une membrane arachnoidienne engainant les radicelles du IX–X fut constatee. La liberation arachnoidienne avec decompression microvasculaire fut realisee. Les suites postoperatoires furent simples. La douleur fut abolie dans un cas, diminuee dans le second. Conclusion Dans la NVGP, l’engainement arachnoidien pourrait participer a la nevralgie, seul ou associe a un conflit neurovasculaire.

Representing 3D shape deformations by linear models in high-dimensional space has many applications in computer vision and medical imaging, such as shape-based interpolation or segmentation. Commonly, using Principal Components Analysis a low-dimensional (affine) subspace of the high-dimensional shape space is determined. However, the resulting factors (the most dominant eigenvectors of the covariance matrix) have global support, i.e. changing the coefficient of a single factor deforms the entire shape. In this paper, a method to obtain deformation factors with local support is presented. The benefits of such models include better flexibility and interpretability as well as the possibility of interactively deforming shapes locally. For that, based on a well-grounded theoretical motivation, we formulate a matrix factorisation problem employing sparsity and graph-based regularisation terms. We demonstrate that for brain shapes our method outperforms the state of the art in local support models with respect to generalisation ability and sparse shape reconstruction, whereas for human body shapes our method gives more realistic deformations., Please cite CVPR 2016 version

Transitive consistency of pairwise transformations is a desirable property of groupwise image registration procedures. The transformation synchronisation method (Bernard et al., 2015) is able to retrieve transitively consistent pairwise transformations from pairwise transformations that are initially not transitively consistent. In the present paper, we present a numerically stable implementation of the transformation synchronisation method for affine transformations, which can deal with very large translations, such as those occurring in medical images where the coordinate origins may be far away from each other. By using this method in conjunction with any pairwise (affine) image registration algorithm, a transitively consistent and unbiased groupwise image registration can be achieved. Experiments involving the average template generation from 3D brain images demonstrate that the method is more robust with respect to outliers and achieves higher registration accuracy compared to reference-based registration.

The post-operative validation of deep brain stimulation electrode displacement and deformation is an important task towards improved DBS targeting. In this paper a method is proposed to align models of deep brain stimulation electrodes that are automatically extracted from post-operative CT imaging in a common coordinate system utilizing the planning data as reference. This enables the assessment of electrode displacement and deformation over the whole length of the trajectory with respect to the pre-operative planning. Accordingly, it enables the estimation of plan deviations in the surgical process as well as cross-patient statistics on electrode deformation, e.g. the bending induced by brain-shift.

International audience; A simple second-order scheme on Cartesian grids for kinetic equations is presented, with emphasis on the accurate enforcement of wall boundary conditions on immersed bodies. This approach preserves at the discrete level the asymptotic limit towards Euler equations up to the wall, thus ensuring a smooth transition towards the hydrodynamic regime. We investigate exact, numerical and experimental test cases for the BGK model in order to assess the accuracy of the method.

Introduction La division du foramen jugulaire en compartiments est sujet a controverse. Le but de ce travail etait d’analyser la compartimentation du foramen jugulaire a la lumiere du concept d’espace interperiosteodural. L’organisation durale du foramen jugulaire laisse apparaitre pour certains, deux compartiments separes par un tissu fibreux ou fibro-osseux : l’un antero-medial ou pars nervosa, contenant le nerf glossopharyngien (IX) et le sinus petreux inferieur ; l’autre postero-lateral ou pars vascularis, plus large, contenant le bulbe superieur de la veine jugulaire interne, les nerfs vague (X) et accessoire (XI) et l’artere meningee posterieure. D’autres, comme Ayeni, nient la notion de compartiments au niveau du foramen jugulaire. Pour certains enfin, il existe trois compartiments separes par de la dure-mere : un compartiment antero-medial ou petreux contenant le sinus petreux inferieur, un compartiment dorsolateral ou sigmoidien contenant le bulbe superieur de la veine jugulaire interne et un compartiment central ou intrajugulaire ou neural, traverse par les IX, X et XI, les foramen de ces nerfs etant separes par un septum dural. Materiels et methodes Douze tetes de cadavres ont ete fixees au formol (10 %) dont 8 injectees au latex-neoprene (PERCAN 671A) et 2 a la gelatine colores a l’encre de chine (systeme arteriel rouge, systeme veineux bleu). Trois sujets ont ete traites pendant 3 mois a l’eau oxygenee, permettant la realisation de coupes coronales et axiales. Les macrophotographies ont ete realisees au boitier 6X6 Hasselblad 500 avec dos numerique et/ou dos argentique (film Fuji Velvia 120, 50ASA, secondairement numerise). Resultats Le sinus sigmoide etait situe dans un espace interperiosteodural jusqu’a sa terminaison situee en arriere et au-dessous des X et XI. Le sinus petreux inferieur – lui-meme situe dans un espace identique – se terminait en avant et au-dessous du IX. L’orifice de penetration durale du X etait d’aspect cribriforme, contrairement a celui du XI, unique. Ces deux nerfs etaient cintres, en haut, par un ligament arciforme de dure-mere encephalique similaire au ligament falciforme du nerf optique. Au-dela de ces orifices, les X et XI n’etaient plus gaines de dure-mere encephalique et devenaient verticaux, dans une gaine durale unique. La gaine durale encephalique du IX se poursuivait, elle, sur 3 mm environ, au-dessus de la jonction sinus petreux inferieur-sinus sigmoide. Au-dela, seule une gaine periostee l’accompagnait dans son segment vertical. Cette gaine periostee emettait un ligament dural horizontal surplombant les X et XI. Conclusion Tel que nous l’avons observe, sur son versant endocrânien, et a la lumiere du concept interperiosteodural, le foramen jugulaire paraissait divise en quatre compartiments.

The alignment of a set of objects by means of transformations plays an important role in computer vision. Whilst the case for only two objects can be solved globally, when multiple objects are considered usually iterative methods are used. In practice the iterative methods perform well if the relative transformations between any pair of objects are free of noise. However, if only noisy relative transformations are available (e.g. due to missing data or wrong correspondences) the iterative methods may fail. Based on the observation that the underlying noise-free transformations can be retrieved from the null space of a matrix that can directly be obtained from pairwise alignments, this paper presents a novel method for the synchronisation of pairwise transformations such that they are transitively consistent. Simulations demonstrate that for noisy transformations, a large proportion of missing data and even for wrong correspondence assignments the method delivers encouraging results., Accepted for CVPR 2015 (please cite CVPR version)

The solution of complex rarefied flows with the BGK equation and the Discrete Velocity Method (DVM) requires a large number of velocity grid points leading to significant computational costs. We propose an adaptive velocity grid approach exploiting the fact that locally in space, the distribution function is supported only by a sub-set of the global velocity grid. The velocity grid is adapted thanks to criteria based on local temperature, velocity and on the enforcement of mass conservation. Simulations in 1D and 2D are presented for different Knudsen numbers and compared to a global velocity grid BGK solution, showing the computational gain of the proposed approach.

The main feature of diluted flows is the presence of both continuum and kinetic regimes in the same field. The ES-BGK model is a kinetic model that preserves the asymptotic properties towards compressible Euler equations in the hydrodynamic regime, yet modeling momentum and kinetic energy diffusion for low Knudsen numbers. Here, this model is discretized by a finite-volume scheme on Cartesian meshes. The scheme is second order up to the possibly moving boundaries. To ensure a smooth transition between the hydrodynamic and the kinetic regime up to the walls, appropriate boundary conditions are devised. As an application, we present the simulation of an unsteady nozzle plume in a very low pressure environment.

In this paper, we provide a detailed survey of 3D Morphable Face Models over the 20 years since they were first proposed. The challenges in building and applying these models, namely capture, modeling, image formation, and image analysis, are still active research topics, and we review the state-of-the-art in each of these areas. We also look ahead, identifying unsolved challenges, proposing directions for future research and highlighting the broad range of current and future applications., ACM Transactions on Graphics (TOG)

KOPPA (Kinetic Octree Parallel PolyAtomic) is a parallel numerical code for the simulation of rarefied gas dynamics. It is based on a library named PABLO (PArallel Balanced Linear Octree) used to manage octree grids in parallel. The main issue with such numerical codes is the very high execution time which can become prohibitive for some industrial applications. Thanks to the SHAPE project, important improvements have been achieved with respect to execution time and scalability. In particular, some parts of the code have been reimplemented to suit better a MIC (Multi Integrated Cores) architecture. So far, the computational time requirements have been decreased by a factor of almost 8 and a good scalability has been obtained up to 64 processors against 16 initially.