374 research outputs found

    Three-dimensional superimposition for patients with facial palsy: an innovative method for assessing the success of facial reanimation procedures

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    Facial palsy is a severe condition that may be ameliorated by facial reanimation, but there is no consensus about how to judge its success. In this study we aimed to test a new method for assessing facial movements based on 3-dimensional analysis of the facial surfaces. Eleven patients aged between 42 and 77 years who had recently been affected by facial palsy (onset between 6 and 18 months) were treated by an operation based on triple innervation: the masseteric to temporofacial nerve branch, 30% of the hypoglossal fibres to the cervicofacial nerve branch, and the contralateral facial nerve through two cross-face sural nerve grafts. Each patient had five stereophotogrammetric scans: at rest, smiling on the healthy side (facial stimulus), biting (masseteric stimulus), moving the tongue (hypoglossal stimulus), and corner-of-the-mouth smile (Mona Lisa). Each scan was superimposed onto the facial model of the "rest" position, and the point-to-point root mean square (RMS) value was automatically calculated on both the paralysed and the healthy side, together with an index of asymmetry. One-way and two-way ANOVA tests, respectively, were applied to verify the significance of possible differences in the RMS and asymmetry index according to the type of stimulus (p = 0.0329) and side (p < 0.0001). RMS differed significantly according to side between the facial stimulus and the masseteric one on the paralysed side (p = 0.0316). Facial stimulus evoked the most asymmetrical movement, whereas the masseteric produced the most symmetrical expression. The method can be used for assessing facial movements after facial reanimation

    Aplastic anemia after pediatric liver transplantation

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    A aplasia de medula é uma das mais raras (<1%) e sérias complicações após o transplante hepático por insuficiência hepática aguda grave viral não A, não B e não C. Esta condição clínica, que acomete simultaneamente o tecido hepático e o hematopoético, foi descrita pela primeira vez em 1987, por Stock, e a fisiopatologia relacionada é uma condição imunomediada, provavelmente secundária à infecção viral desconhecida, e associada a grave prognóstico. A recuperação espontânea da aplasia medular adquirida habitualmente é muito rara e 50%-70% dos pacientes respondem ao tratamento imunossupressor com ciclosporina A (CsA) e glubulina antitimocítica (ATG), mesmo após o transplante hepático. Além do tratamento imunossupressor, outra opção é o transplante de medula óssea (TMO). Apresentamos o caso de uma criança com aplasia medular grave após transplante hepático, por insuficiência hepática aguda grave, que recebeu tratamento imunossupressor com CsA e ATG e evoluiu com recuperação completa das três séries do hemograma.Aplastic anemia (AA) is one of the rarest (<1%) and most serious complications of liver transplantation for fulminant non-A, non-B and non-C hepatitis. It was first described in 1987 by Stock; the mechanism involved is an immunologically mediated condition secondary to an unknown viral infection. The disease is associated with a dismal prognosis. Spontaneous recovery from acquired AA is very rare however some patients (50-70%) recover after immunosuppressive therapy, such as Cyclosporin A (CsA) and Antithymocyte globulin (ATG), even after liver transplantation. Another treatment option is bone marrow transplantation. We report on a child who developed AA following liver transplantation for fulminant viral hepatitis that was treated with intensive immunosuppression including CsA and ATG and achieved complete recovery

    Anatomical variants of sphenoid sinuses pneumatisation: a CT scan study on a Northern Italian population

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    Sphenoid bone may be affected by different variants of pneumatisation, which have a relevant importance from a clinical and surgical point of view. The description of such variants in different populations may give useful information. However, few articles describe the variability of sphenoid pneumatised structures and none of them focuses on Northern Italian population. Variants of pneumatisation of sphenoid bone were described in a sample of 300 Northern Italian patients who underwent a CT scan. More than fifty-seven percent of patients showed a form of anatomical variant: the most common form was the pneumatised pterygoid processes (39.6%), followed by dorsum sellae (32.9%) and clinoid processes (20.3%), without statistically significant differences between males and females (p\ua0>\ua00.01). In 26.3% of patients, a combined pneumatisation of these three structures was observed, being the combination pterygoid processes-dorsum sellae the most frequent (11.3%). In 9.3%, all the three sphenoid structures were affected. This article is the first description of the prevalence of different variants of pneumatisation in a Northern Italian population: the occurrence of such forms has to be acknowledged for their possible clinical and surgical consequences

    Anatomical Characteristics Of Intrapetrous Carotid Artery : A 3d Segmentation Study On Head Ct-Scan

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    The intrapetrous portion of internal carotid artery (IPCA) is one of the most unexplored anatomical regions, and its three-dimensional reconstruction in living subjects is still missing. The present study aims at describing IPCA on 3D models extracted from head CT-scans. The intrapetrous carotid artery was manually segmented on head CT-scans of 100 healthy patients free from vascular and neurological pathologies (50 males and 50 females aged between 18 and 91 years). Angles of the posterior and anterior genu, diameter and length of the horizontal portion, and volume of the entire canal were calculated through VAM\uae software. Statistically significant differences according to sex and side were assessed through two-way ANOVA test (p&lt;0.05). Correlation of each measurement with age was calculated as well. On average the angles of the posterior and anterior genu were 120.1\ub110.4\ub0 and 118.0\ub110.0\ub0 in males, 119.5\ub19.2\ub0 and 117.6\ub110.3\ub0 in females, respectively, without statistically significant differences according to sex or side (p&gt;0.05). Average length and diameter of the horizontal part were respectively 25.5\ub12.9 mm and 5.8\ub10.8 mm in males, 24.0\ub12.3 mm and 5.3\ub10.8 mm in females. The volume of IPCA was 0.941\ub10.215 cm3 in males, and 0.752\ub10.159 cm3 in females. Length and diameter of horizontal portion, and volume of IPCA showed statistically significant differences according to sex (p&lt;0.05). No correlation with age was found. This study first provided data concerning not only linear and angular measurements, but also volumes of IPCA, useful in planning surgical interventions of the cranial base

    Coupling Molecular Dynamics and Direct Simulation Monte Carlo using a general and high-performance code coupling library

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    A domain-decomposed method to simultaneously couple the classical Molecular Dynamics (MD) and Direct Simulation Monte Carlo (DSMC) methods is proposed. This approach utilises the MPI-based general coupling library, the Multiscale Universal Interface. The method provides a direct coupling strategy and utilises two OpenFOAM based solvers, mdFoam+ and dsmcFoam+, enabling scenarios where both solvers assume one discrete particle is equal to one molecule or atom. The ultimate goal of this work is to enable complex multi-scale simulations involving micro, meso and macroscopic elements, as found with problems like evaporation.Results are presented to show the fundamental capabilities of the method in terms of mass and kinetic energy conservation between simulation regions handled by the different solvers. We demonstrate the capability of the method by deploying onto a large supercomputing resource, with attention paid to the scalability for a canonical NVT ensemble (a constant number of atoms N, constant volume V and constant temperature T) of Argon atoms. The results show that the method performs as expected in terms of mass conservation and the solution is also shown to scale reasonably on a supercomputing resource, within the known performance limits of the coupled codes. The wider future of this work is also considered, with focus placed on the next steps to expand the capabilities of the methodology to allow for indirect coupling (where the coarse-graining capability of the DSMC method is used), as well as how this will then fit into a larger coupled framework to allow a complete micro-meso-macro approach to be tackled

    What is life? A perspective of the mathematical kinetic theory of active particles

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    The modeling of living systems composed of many interacting entities is treated in this paper with the aim of describing their collective behaviors. The mathematical approach is developed within the general framework of the kinetic theory of active particles. The presentation is in three parts. First, we derive the mathematical tools, subsequently, we show how the method can be applied to a number of case studies related to well defined living systems, and finally, we look ahead to research perspectives

    A novel method of morphological and metrical assessment by 3D-3D superimposition for the assessment of facial mimicry: a pilot study

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    The assessment of facial mimicry has a relevant importance not only in anatomy, but also in clinics for the evaluation of facial performances in patients affected by neurological or muscular impairments, and in forensic medicine, for the standardization of individualizing markers useful for personal identification. The application of modern 3D image acquisition systems may provide reliable results, especially for what concerns the analysis of facial surfaces: however, the comparison of anatomical structures needs standardized, reproducible protocols in order to provide comparable data. This study aims at exposing a novel and promising method for comparing 3D profiles, useful for quantifying alteration of facial structures in different conditions. Ten male adults, aged between 30 and 40 years underwent to four acquisitions by stereophotogrammetry (VECTRA-3D®: Canfield Scientific, Inc., Fairfield, NJ) with different expressions (neutral, happy, sad, angry, surprised). On each 3D facial model, 9 landmarks (right and left endocanthion, exocanthion, cheilion: on the midline, selion, pronasale, subnasale) were identified using VAM® software; the acquisition of each individual performed with happy, sad, angry and surprised expression was then superimposed to the neutral one, in order to reach the best match between the corresponding landmarks. This procedure allowed the operator to obtain also a chromatic sheet of the face, where in blue are colored the growing zones and in red the zones which showed a decrease. In all the cases, the RMS value (Root Mean Square) between the two models was calculated as well. The highest difference in comparison with the neutral standard was shown by the happy expression (mean RMS 4.11 mm, SD 1.13 mm), followed by the surprised expression (mean RMS 2.74 mm, SD 1.02 mm) and the sad (mean RMS 1.3 mm, SD 0.49 mm) and angry ones (mean RMS 1.21 mm, SD 0.37 mm). The happy and surprised expressions showed a wide modification of the mouth, chin and cheek regions, whereas the sad and angry expressions were affected by slight and more variable alterations. This pilot study shows that the 3D-3D superimposition may provide reliable results concerning facial alteration due to mimicry, which may be useful for clinical purposes: further studies are needed in order to test the variability of morphological and metrical parameters according to age and sex

    A view to the future: standardizing 3D-3D superimposition for identification from next generation video surveillance systems

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    The identification of culprits from videosurveillance systems brings about relevant problems for what concerns the reliability of comparison and quantification of the degree of match between the culprit and the suspect. The actual videosurveillance give only 2D images of the culprit, which can be compared to a 3D model of the suspect’s face in 2D-3D superimposition. However, in the next future the videosurveillance systems will provide a 3D image of the filmed persons, which may allow the operator to perform 3D-3D superimposition. This study aims at exposing a pilot study based on 10 male subjects: the face from each individual underwent two acquisitions by stereophotogrammetry. On each 3D facial model, 9 landmarks (right and left: en, ex, ch: midline: se, gn, prn) were identified by VAM® software; the acquisitions of each individual were then superimposed with the models of all the other subjects in order to reduce the distance between the corresponding points. The RMS value (Root Mean Square) between the two models was then calculated. When the two superimposed models belonged to the same individual, RMS value was in mean 1.58 mm (SD: 0.61 mm), whereas when the two models were taken from different persons, the same value was 4.54 mm (SD: 2.02 mm) with a statistically significant (p&lt;0.0001). This pilot study shows that the judgment of identification based on 3D-3D superimposition may provide reliable results. The improvement specific methods of 3D-3D comparison may provide in the next future relevant advantages in this field of forensic anthropology
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