662 research outputs found

    Facial Paralysis Grading Based on Dynamic and Static Features

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    Peripheral facial nerve palsy, also known as facial paralysis (FP), is a common clinical disease, which requires subjective judgment and scoring based on the FP scale. There exists some automatic facial paralysis grading methods, but the current methods mostly only consider either static or dynamic features, resulting in a low accuracy rate of FP grading. This thesis proposes an automatic facial paralysis assessment method including both static and dynamic characteristics. The first step of the method performs preprocessing on the collected facial expression videos of the subjects, including rough video interception, video stabilization, keyframe extraction, image geometric normalization and gray-scale normalization. Next, the method selects as keyframes no facial expression state and maximum facial expression state in the image data to build the the research data set. Data preprocessing reduces errors, noise, redundancy and even errors in the original data. The basis for extracting static and dynamic features of an image is to use Ensemble of Regression Trees algorithm to determine 68 facial landmarks. Based on landmark points, image regions of image are formed. According to the Horn-Schunck optical flow method, the optical flow information of parts of the face are extracted, and the dynamic characteristics of the optical flow difference between the left and right parts are calculated. Finally, the results of dynamic and static feature classification are weighted and analyzed to obtain FP ratings of subjects. A 32-dimensional static feature is fed into the support vector machine for classification. A 60-dimensional feature vector of dynamical aspects is fed into a long and short-term memory network for classification. Videos of 30 subjects are used to extract 1419 keyframes to test the algorithm. The accuracy, precision, recall and f1 of the best classifier reach 93.33%, 94.29%, 91.33% and 91.87%, respectively.Perifeerinen kasvojen hermohalvaus, joka tunnetaan myös nimellä kasvojen halvaus (FP), on yleinen kliininen sairaus, joka vaatii subjektiivista arviointia ja FP -asteikon pisteytystä. Joitakin automaattisia kasvohalvauksen luokittelumenetelmiä on olemassa, mutta yleensä ottaen ne punnitsevat vain joko staattisia tai dynaamisia piirteitä. Tässä tutkielmassa ehdotetaan automaattista kasvojen halvaantumisen arviointimenetelmää, joka kattaa sekä staattiset että dynaamiset ominaisuudet. Menetelmän ensimmäinen vaihe suorittaa ensin esikäsittelyn kohteiden kerätyille kasvojen ilmevideoille, mukaan lukien karkea videon sieppaus, videon vakautus, avainruudun poiminta, kuvan geometrinen normalisointi ja harmaasävyjen normalisointi. Seuraavaksi menetelmä valitsee avainruuduiksi ilmeettömän tilan ja kasvojen ilmeiden maksimitilan kuvadatasta kerryttäen tutkimuksen data-aineiston. Tietojen esikäsittely vähentää virheitä, kohinaa, redundanssia ja jopa virheitä alkuperäisestä datasta. Kuvan staattisten ja dynaamisten piirteiden poimimisen perusta on käyttää Ensemble of Regression Trees -algoritmia 68 kasvojen merkkipisteiden määrittämiseen. Merkkipisteiden perusteella määritellään kuvan kiinnostavat alueet. Horn-Schunckin optisen virtausmenetelmän mukaisesti poimitaan optisen virtauksen tiedot joistakin kasvojen osista, ja dynaaminen luonnehdinta lasketaan vasempien ja oikeiden osien välille. Lopuksi dynaamisen ja staattisen piirteiden luokittelun tulokset painotetaan ja analysoidaan kattavasti koehenkilöiden FP-luokitusten saamiseksi. 32- ulotteinen staattisten piirteiden vektori syötetään tukivektorikoneeseen luokittelua varten. 60-ulotteinen dynaamisten piirteiden ominaisuusvektori syötetään pitkän ja lyhyen aikavälin muistiverkkoon luokittelua varten. Parhaan luokittelijan tarkkuus, täsmällisyys, palautustaso ja f1 saavuttavat arvot 93,33%, 94,29%, 91,33% ja 91,87%

    Severity scoring approach using modified optical flow method and lesion identification for facial nerve paralysis assessment

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    The facial nerve controls facial movement and expression. Hence, a patient with facial nerve paralysis will experience affected social interactions, psychological distress, and low self-esteem. Upon the first presentation, it is crucial to determine the severity level of the paralysis and take out the possibility of stroke or any other serious causes by recognising the type of lesion in preventing any mistreatment of the patient. Clinically, the facial nerve is assessed subjectively by observing voluntary facial movement and assigning a score based on the deductions made by the clinician. However, the results are not uniform among different examiners evaluating the same patients. This is extremely undesirable for both medical diagnostic and treatment considerations. Acknowledging the importance of this assessment, this research was conducted to develop a facial nerve assessment that can classify both the severity level of facial nerve function and also the types of facial lesion, Upper Motor Neuron (UMN) and Lower Motor Neuron (LMN), in facial regional assessment and lesion assessment, respectively. For regional assessment, two optical flow techniques, Kanade-Lucas-Tomasi (KLT) and Horn-Schunck (HS) were used in this study to determine the local and global motion information of facial features. Nevertheless, there is a problem with the original KLT which is the inability of the Eigen features to distinguish the normal and patient subjects. Thus, the KLT method was modified by introducing polygonal measurements and the landmarks were placed on each facial region. Similar to the HS method, the multiple frames evaluation was proposed rather than a single frame evaluation of the original HS method to avoid the differences between frames becoming too small. The features of these modified methods, Modified Local Sparse (MLS) and Modified Global Dense (MGD), were combined, namely the Combined Modified Local-Global (CMLG), to discover both local (certain region) and global (entire image) flow features. This served as the input into the k-NN classifier to assess the performance of each of them in determining the severity level of paralysis. For the lesion assessment, the Gabor filter method was used to extract the wrinkle forehead features. Thereafter, the Gabor features combined with the previous features of CMLG, by focusing only on the forehead region to evaluate both the wrinkle and motion information of the facial features. This is because, in an LMN lesion, the patient will not be able to move the forehead symmetrically during the rising eyebrows movement and unable to wrinkle the forehead due to the damaged frontalis muscle. However, the patient with a UMN lesion exhibits the same criteria as a normal subject, where the forehead is spared and can be lifted symmetrically. The CMLG technique in regional assessment showed the best performance in distinguishing between patient and normal subjects with an accuracy of 92.26% compared to that of MLS and MGD, which were 88.38% and 90.32%, respectively. From the results, some assessment tools were developed in this study namely individual score, total score and paralysis score chart which were correlated with the House-Brackmann score and validated by a medical professional with 91.30% of accuracy. In lesion assessment, the combined features of Gabor and CMLG on the forehead region depicted a greater performance in distinguishing the UMN and LMN lesion of the patient with an accuracy of 89.03% compared to Gabor alone, which was 78.07%. In conclusion, the proposed facial nerve assessment approach consisting of both regional assessment and lesion assessment is capable of determining the level of facial paralysis severity and recognising the type of facial lesion, whether it is a UMN or LMN lesion

    Brain Computer Interfaces and Emotional Involvement: Theory, Research, and Applications

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    This reprint is dedicated to the study of brain activity related to emotional and attentional involvement as measured by Brain–computer interface (BCI) systems designed for different purposes. A BCI system can translate brain signals (e.g., electric or hemodynamic brain activity indicators) into a command to execute an action in the BCI application (e.g., a wheelchair, the cursor on the screen, a spelling device or a game). These tools have the advantage of having real-time access to the ongoing brain activity of the individual, which can provide insight into the user’s emotional and attentional states by training a classification algorithm to recognize mental states. The success of BCI systems in contemporary neuroscientific research relies on the fact that they allow one to “think outside the lab”. The integration of technological solutions, artificial intelligence and cognitive science allowed and will allow researchers to envision more and more applications for the future. The clinical and everyday uses are described with the aim to invite readers to open their minds to imagine potential further developments

    Functional assessment after peripheral nerve injury : kinematic model of the hindlimb of the rat

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    Doutoramento em Motricidade Humana na especialidade de FisioterapiaGait analysis is increasingly used on research methodology to assess dynamics aspects of functional recovery after peripheral nerve injury in the rat model, which ultimately is the goal of treatment and rehabilitation. In this thesis we studied nerve regeneration using techniques of molecular and cellular biology. Functional recovery was evaluated using the sciatic functional index (SFI), the static sciatic index (SSI), the extensor postural thrust (EPT), the withdrawal reflex latency (WRL) and hindlimb kinematics. Nerve fiber regeneration was assessed by quantitative stereological analysis and electron microscopy. From our results, hybrid chitosan membranes after sciatic nerve crush, either alone or enriched with N1E-115 neural cells, may represent an effective approach for the improvement of the clinical outcome in patients receiving peripheral nerve surgery. Collagen membrane, with or without neural cell enrichment, did not lead to any significant improvement in most of functional and stereological predictors of nerve regeneration that we have assessed, with the exception of EPT. Extending the kinematic analysis during walking to the hip joint improved sensitivity of this functional test. For motor rehabilitation, either active or passive exercises positively affect sciatic nerve regeneration after a crush injury, possibly mediated by a direct mechanical effect onto the regenerating nerve.FCT- Fundação para a Ciência e Tecnologi

    Susceptibility to Neurodegenerative Disorders: Insights from Paleogenomic Data

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    Ancient human genome data that has accumulated in recent years can be employed to establish the spatiotemporal trajectories of genetic variants associated with human diseases. Such knowledge might illuminate if and how past adaptations impact contemporary human health and medicine. Scarcely any studies have yet been attempted to evaluate the genetic susceptibility to neurodegenerative disorders in ancient human communities. Using publicly available ancient human genome-wide data the present study evaluates the molecular predisposition to neurodegenerative disorders in ancient human communities. To this end we screened the ancient genome-wide data for the presence of variants unequivocally associated with neurodegenerative disorders in modern populations, and their historical and geographic prevalence was assessed. These variants are two rare variants in the LRRK2 gene associated with Mendelian Parkinson\u27s disease, a pathogenic variant in the CRH gene, associated with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE), and a rare variant in the TREM2 gene, a possible risk modifier associated with Alzheimer\u27s disease. Our assessment of the historical and geographic prevalence indicates differing spatiotemporal frequency dynamics for these clinically significant variants. Neurodegenerative disorders are often with poorly understood pathogenesis that might be elucidated by studying the interaction of past genetic variability with ecological and evolutionary factors such as adverse environmental conditions, specific selective pressures, periods of population isolation and admixture processes. Data on molecular predisposition to neurodegenerative disorders in ancient genomes is instructive to modern medical diagnostic and therapeutic practices

    Deep human face analysis and modelling

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    Human face appearance and motion play a significant role in creating the complex social environments of human civilisation. Humans possess the capacity to perform facial analysis and come to conclusion such as the identity of individuals, understanding emotional state and diagnosing diseases. The capacity though is not universal for the entire population, where there are medical conditions such prosopagnosia and autism which can directly affect facial analysis capabilities of individuals, while other facial analysis tasks require specific traits and training to perform well. This has lead to the research of facial analysis systems within the computer vision and machine learning fields over the previous decades, where the aim is to automate many facial analysis tasks to a level similar or surpassing humans. While breakthroughs have been made in certain tasks with the emergence of deep learning methods in the recent years, new state-of-the-art results have been achieved in many computer vision and machine learning tasks. Within this thesis an investigation into the use of deep learning based methods for facial analysis systems takes place, following a review of the literature specific facial analysis tasks, methods and challenges are found which form the basis for the research findings presented. The research presented within this thesis focuses on the tasks of face detection and facial symmetry analysis specifically for the medical condition facial palsy. Firstly an initial approach to face detection and symmetry analysis is proposed using a unified multi-task Faster R-CNN framework, this method presents good accuracy on the test data sets for both tasks but also demonstrates limitations from which the remaining chapters take their inspiration. Next the Integrated Deep Model is proposed for the tasks of face detection and landmark localisation, with specific focus on false positive face detection reduction which is crucial for accurate facial feature extraction in the medical applications studied within this thesis. Evaluation of the method on the Face Detection Dataset and Benchmark and Annotated Faces in-the-Wild benchmark data sets shows a significant increase of over 50% in precision against other state-of-the-art face detection methods, while retaining a high level of recall. The task of facial symmetry and facial palsy grading are the focus of the finals chapters where both geometry-based symmetry features and 3D CNNs are applied. It is found through evaluation that both methods have validity in the grading of facial palsy. The 3D CNNs are the most accurate with an F1 score of 0.88. 3D CNNs are also capable of recognising mouth motion for both those with and without facial palsy with an F1 score of 0.82

    Arch Pediatr Adolesc Med

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    ObjectiveTo develop a novel diagnostic algorithm for Lyme disease among children with facial palsy by integrating public health surveillance data with traditional clinical predictors.DesignRetrospective cohort study.SettingChildren\ue2\u20ac\u2122s Hospital Boston emergency department,1995\ue2\u20ac\u201c2007Patients264 children under age 20 years presenting with peripheral facial palsy who were evaluated for Lyme diseaseMain outcome measuresMultivariate regression was used to identify independent clinical and epidemiologic predictors of Lyme facial palsy.Results65% of children from high-risk counties during Lyme season tested positive, compared to 5% of children without geographic or seasonal risk factors present. Among patients with both seasonal and geographic risk factors, 80% with one clinical risk factor (fever or headache) and 100% with two clinical factors had Lyme. Factors independently associated with Lyme facial palsy were presentation from June-November (odds ratio 25, 95% CI 8.3\ue2\u20ac\u201c113), residence in a county where the most recent three year average Lyme incidence exceeded 4 cases/100,000 (18, 6.5\ue2\u20ac\u201c69), fever (3.9, 1.5\ue2\u20ac\u201c11), and headache (2.7, 1.3\ue2\u20ac\u201c5.8). Clinical experts correctly treated 68/94 (72%) patients with Lyme facial palsy, but a tool incorporating geographical and seasonal risk identified all 94 cases.ConclusionsMost clinicians intuitively integrate geographic information into Lyme disease management, but we demonstrate quantitatively how formal use of geographically-based incidence in a clinical algorithm improves diagnostic accuracy. These findings demonstrate potential for improved outcomes from investments in health information technology that foster bidirectional communication between public health and clinical settings.G08 LM009778/LM/NLM NIH HHS/United StatesG08LM009778/LM/NLM NIH HHS/United StatesK01HK000055/HK/PHITPO CDC HHS/United StatesP01HK000016/HK/PHITPO CDC HHS/United StatesP01HK000088-01/HK/PHITPO CDC HHS/United StatesR01 LM007677/LM/NLM NIH HHS/United StatesR01 LM007677/LM/NLM NIH HHS/United States2013-05-03T00:00:00Z21199982PMC364402

    Effectiveness of intensive physiotherapy for gait improvement in stroke: systematic review

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    Introduction: Stroke is one of the leading causes of functional disability worldwide. Approximately 80% of post-stroke subjects have motor changes. Improvement of gait pattern is one of the main objectives of physiotherapists intervention in these cases. The real challenge in the recovery of gait after stroke is to understand how the remaining neural networks can be modified, to be able to provide response strategies that compensate for the function of the affected structures. There is evidence that intensive training, including physiotherapy, positively influences neuroplasticity, improving mobility, pattern and gait velocity in post-stroke recovery. Objectives: Review and analyze in a systematic way the experimental studies (RCT) that evaluate the effects of Intensive Physiotherapy on gait improvement in poststroke subjects. Methodology: Were only included all RCT performed in humans, without any specific age, that had a clinical diagnosis of stroke at any stage of evolution, with sensorimotor deficits and functional gait changes. The databases used were: Pubmed, PEDro (Physiotherapy Evidence Database) and CENTRAL (Cochrane Center Register of Controlled Trials). Results: After the application of the criteria, there were 4 final studies that were included in the systematic review. 3 of the studies obtained a score of 8 on the PEDro scale and 1 obtained a score of 4. The fact that there is clinical and methodological heterogeneity in the studies evaluated, supports the realization of the current systematic narrative review, without meta-analysis. Discussion: Although the results obtained in the 4 studies are promising, it is important to note that the significant improvements that have been found, should be carefully considered since pilot studies with small samples, such as these, are not designed to test differences between groups, in terms of the effectiveness of the intervention applied. Conclusion: Intensive Physiotherapy seems to be safe and applicable in post-stroke subjects and there are indications that it is effective in improving gait, namely speed, travelled distance and spatiotemporal parameters. However, there is a need to develop more RCTs with larger samples and that evaluate the longterm resultsN/
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