Déformation de la peau d'un personnage avec prise en compte des contacts

National audienceLors de l'animation d'un maillage représentant la peau d'un personnage ou d'un animal par exemple, des techniques dites de skinning sont utilisées pour le déformer au niveau des articulations. Bien que très populaires dans l'industrie pour leur très faible coût d'évaluation, les techniques de skinning géométrique comme le LBS (Linear Blending Skinning) ou les dual quaternions, ne permettent pas d'imiter de façon crédible les déformations des membres. Pour mieux capturer le comportement de la peau, d'autres méthodes basées seulement sur le maillage, utilisent des calculs coûteux comme la détection de collisions ou la correction de volume. Toutefois ces approches restent seulement adaptées au rendu hors ligne. Nous présentons la première méthode temps réel produisant une déformation du maillage en prenant en compte le contact de la peau et, éventuellement, le gonflement des muscles. Nous proposons d'utiliser de façon conjointe le maillage et une représentation volumique. Le maillage est approximé avec une surface implicite qui nous permet de le déformer de façon plausible tout en traitant les collisions et en conservant les détails du maillage

Implicit Skinning: Real-Time Skin Deformation with Contact Modeling

SIGGRAPH 2013 Conference ProceedingsInternational audienceGeometric skinning techniques, such as smooth blending or dualquaternions, are very popular in the industry for their high performances, but fail to mimic realistic deformations. Other methods make use of physical simulation or control volume to better capture the skin behavior, yet they cannot deliver real-time feedback. In this paper, we present the first purely geometric method handling skin contact effects and muscular bulges in real-time. The insight is to exploit the advanced composition mechanism of volumetric, implicit representations for correcting the results of geometric skinning techniques. The mesh is first approximated by a set of implicit surfaces. At each animation step, these surfaces are combined in real-time and used to adjust the position of mesh vertices, starting from their smooth skinning position. This deformation step is done without any loss of detail and seamlessly handles contacts between skin parts. As it acts as a post-process, our method fits well into the standard animation pipeline. Moreover, it requires no intensive computation step such as collision detection, and therefore provides real-time performances

The ANTENATAL multicentre study to predict postnatal renal outcome in fetuses with posterior urethral valves: objectives and design

Abstract Background Posterior urethral valves (PUV) account for 17% of paediatric end-stage renal disease. A major issue in the management of PUV is prenatal prediction of postnatal renal function. Fetal ultrasound and fetal urine biochemistry are currently employed for this prediction, but clearly lack precision. We previously developed a fetal urine peptide signature that predicted in utero with high precision postnatal renal function in fetuses with PUV. We describe here the objectives and design of the prospective international multicentre ANTENATAL (multicentre validation of a fetal urine peptidome-based classifier to predict postnatal renal function in posterior urethral valves) study, set up to validate this fetal urine peptide signature. Methods Participants will be PUV pregnancies enrolled from 2017 to 2021 and followed up until 2023 in >30 European centres endorsed and supported by European reference networks for rare urological disorders (ERN eUROGEN) and rare kidney diseases (ERN ERKNet). The endpoint will be renal/patient survival at 2 years postnatally. Assuming α = 0.05, 1–β = 0.8 and a mean prevalence of severe renal outcome in PUV individuals of 0.35, 400 patients need to be enrolled to validate the previously reported sensitivity and specificity of the peptide signature. Results In this largest multicentre study of antenatally detected PUV, we anticipate bringing a novel tool to the clinic. Based on urinary peptides and potentially amended in the future with additional omics traits, this tool will be able to precisely quantify postnatal renal survival in PUV pregnancies. The main limitation of the employed approach is the need for specialized equipment. Conclusions Accurate risk assessment in the prenatal period should strongly improve the management of fetuses with PUV

Aphtes et ulcérations buccales

National audienceAphthous ulcers are painful ulcerations located on the mucous membrane, generally in the mouth, less often in the genital area. Three clinical forms of aphthous ulcers have been described: minor aphthous ulcers, herpetiform aphthous ulcers and major aphthous ulcers. Many other conditions presenting with oral bullous or vesiculous lesions orulcerations and erosions can be mistaken for aphthous ulcers. Currently, treatment of aphthous ulcers is palliative and symptomatic. Topical treatments (topical anesthetics, topical steroids and sucralfate) are the first line therapy. Recurrent aphthous stomatitis (RAS) is defined by the recurrence of oral aphthous ulcers at least 4 times per year. RAS is often idiopathic but can be associated with gastro-intestinal diseases (i.e. celiac disease, inflammatory bowel diseases), nutritional deficiencies (iron, folates…), immune disorders (HIV infection, neutropenia) and rare syndromes. Behçet's disease is a chronic, inflammatory, disease whose main clinical feature is recurrent bipolar aphthosis. Colchicine associated with topical treatments constitutes a suitable treatment of most RAS. Thalidomide is the most effective treatment of RAS but its use is limited by frequent adverse effects. Oral ulcers can be related to a wide range of conditions that constitute the differential diagnoses of aphthous ulcers. Oral ulcers are classified into three main groups: acute ulcers with abrupt onset and short duration, recurrent ulcers (mainly due to postherpetic erythema multiforme) and chronic ulcers (with slow onset and insidious progression). Acute oral ulcers are due to trauma, bacterial infections (including acute necrotizing ulcerative gingivitis), deep fungal infection, gastro-intestinal (namely inflammatory bowel disease) or systemic diseases. Chronic oral ulcers may be drug-induced, or due to benign or malignant tumors. Every oral solitary chronic ulcer should be biopsied to rule out squamous cell carcinoma. A solitary palatal ulcer can be related with necrotizing sialometaplasia

Angiosarcoma as a potential consequence of autologous lymph node transplantation for lymphoedema

International audienceWith high interest have we read the article by Vignes et al., recording complications (lymphoedema, lymphocoele, hydrocoele and donor-site pain) in patients undergoing autologous lymph node transplantation (ALNT) for limb lymphoedema.1 In addition, we recently witnessed a fatal case of angiosarcoma in a 21-year-old woman. We were amazed by the unusual presentation of this aggressive tumour in such a young otherwise healthy woman, located in the right groin exactly at the site of ALNT performed 14 and 7 years before

Automatic shape adjustment at joints for the implicit skinning

International audienceThe implicit skinning is a geometric interactive skinning method, for skeleton-based animations, enabling plausible deformations at joints while resolving skin self-collisions. Even though requiring a few user interactions to be adequately parameterized, some efforts have to be spent on the edition of the shapes at joints. In this research, we introduce a dedicated optimisation framework for automatically adjusting the shape of the surfaces generating the deformations at joints when they are rotated during an animation. This approach directly fits in the implicit skinning pipeline and it has no impact on the algorithm performance during animation. Starting from the mesh partition of the mesh representing the animated character, we propose a dedicated hole filling algorithm based on a particle system and a power crust meshing. We then introduce a procedure optimizing the shape of the filled mesh when it rotates at the joint level. This automatically generates plausible skin deformation when joints are rotated without the need of extra user editing

Efficacy of vedolizumab in granulomatous cheilitis refractory to TNFα inhibitors

International audienc

Déformation de la peau d'un personnage avec prise en compte des contacts

National audienceLors de l'animation d'un maillage représentant la peau d'un personnage ou d'un animal par exemple, des techniques dites de skinning sont utilisées pour le déformer au niveau des articulations. Bien que très populaires dans l'industrie pour leur très faible coût d'évaluation, les techniques de skinning géométrique comme le LBS (Linear Blending Skinning) ou les dual quaternions, ne permettent pas d'imiter de façon crédible les déformations des membres. Pour mieux capturer le comportement de la peau, d'autres méthodes basées seulement sur le maillage, utilisent des calculs coûteux comme la détection de collisions ou la correction de volume. Toutefois ces approches restent seulement adaptées au rendu hors ligne. Nous présentons la première méthode temps réel produisant une déformation du maillage en prenant en compte le contact de la peau et, éventuellement, le gonflement des muscles. Nous proposons d'utiliser de façon conjointe le maillage et une représentation volumique. Le maillage est approximé avec une surface implicite qui nous permet de le déformer de façon plausible tout en traitant les collisions et en conservant les détails du maillage

Contributions of spect/ct imaging to the lymphoscintigraphic investigations of the lower limb lymphedema

International audienceLymphoscintigraphy is a safe and reliable technique for investigating lymphedema. However, interpretation of delayed planar conventional imaging may be questionable due to the superimposition of soft tissues. Therefore, the aim of this retrospective study was to evaluate the contribution of single photon emission computed tomography! computed tomography (SPECT/CT) to lymphoscintigraphic investigation in a selected population with abnormal interstitial activity. Forty one patients with lower limb lymphedema either primary (n=17) or secondary (n=5), or associated with chronic venous insufficiency (n=19) underwent lymphoscintigraphy according to a standard protocol. SPECT/CT imaging that started immediately after planar imaging covered the part of the lower limbs with the most significant interstitial activity. The CT images were also analyzed separately to identify the typical honeycomb pattern of lymphedema. SPECT/CT identified additional abnormalities in vessels and soft tissues in 19 patients (46%). The additional information, primarily related to dermal collateralization of flow, dermal backflow, lymphangioma, and lymphorrhea, aided in understanding the physiopathology of edema and may have influenced management in 35 patients (85%). The honeycomb appearance of the soft tissues was noted on CT in most patients (90%). This study suggests that SPECT/CT is a promising addition to planar imaging in lymphoscintigraphic investigations of lymphedema

Generalized lymphedema associated with neurologic signs (GLANS) syndrome: A new entity?

International audienceBackground: Primary lymphedema in children, especially generalized disease with facial involvement, is rare. Objective: We sought to report 3 childhood cases of lymphedema with associated neurologic findings and to provide a pathophysiologic explanation for this association. Methods: Clinical observations, electroencephalography, and neuroimaging studies were evaluated. Microcomparative genomic hybridization was performed in 1 case. Results: The 3 children had primary lymphedema of all 4 limbs and the face. This was confirmed by lymphoscintigraphy, which showed hypoplasia of vessels and hypofixation of lymph nodes. They had nonspecific neurologic disorders and electroencephalography abnormalities, without intellectual deficit. Neuroimaging revealed normal findings. Microcomparative genomic hybridization in 1 patient revealed no cytogenetic anomaly. The outcome was fatal in 1 case with development of visceral lymphedema and coma. Limitations: Genetic studies were performed in only 1 case. Conclusion: These observations suggest that neurologic assessment and electroencephalography are indicated for patients with lymphedema of the limbs and face to identify this syndrome