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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Craniofacial pattern profile analysis of individuals with frontonasal malformation

Hiester, John David, 1964- January 1994 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Frontonasal malformation, FNM, was first described by Hoppe in 1859. FNM is an anomaly that is characterized by ocular hypertelorism, broad nasal root, lack of a nasal tip, V-shaped hair, prolongation onto the forehead (widow's peak), anterior cranium bifidum occultum, median facial cleft affecting the nose, upper lip, and/or palate, and uni- or bilateral clefting of the ala nasi. The anomalies noted in FNM may be explained as a single malformation. If the nasal capsule fails to develop properly, the primitive brain vesicle fills the space normally occupied by the capsule, thus producing anterior cranium bifidum occultum, an arrest in the positioning of the eyes, and a lack of formation of the nasal tip. The condition presents clinically with variable expressions as sporadic cases and infrequently in familial cases. The present study is the first attempting to quantify and characterize FNM via anatomic radiographic measurements. The lateral (LA) and posterior-anterior (PA) cephalometric radiographs of twenty-four individuals, both sporadic and familial, with FNM were analyzed for comparison of linear and angular measurements with previously published data of a "normal," i.e. unaffected, population standard. Usual and customary cephalometric points were identified and located, then digitized into the computer. Twenty-nine measurements included the previously diagnosed anomalous features of hypertelorism, medial nasal cavity, and palatal shelves, as well as other facial features. The radiographs of individuals with FNM have anatomic features that are unusual and distinct to the specific malformation. The data from this research suggest that patients with FNM, regardless of a genetic or sporadic predisposition, have a midface deficiency in height and depth, an increased interorbital width with possible increased orbital socket width, and a longer zygomatic buttress. Also, the familial cases tend to have a flatter cranial base than the sporadic cases. Furthermore, the familial patients might be a different type of FNM since this subgroup shows narrower zygomatic widths. The patients with surgical procedures demonstrated improvement different from the growth of those patients who did not have surgery. The hypothesis that the facies of a patient with frontonasal malformation is different from the "normal" control population is supported by this research. The differences between the familial and sporadic patients tend to support the general theory that genetic predisposition is less severe than FNM that occurs randomly.
2

3D CBCT analysis of the frontal sinus and its relationship to forensic identification

Krus, Bianaca S. January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The positive identification of human remains that are decomposed, burnt, or otherwise disfigured can prove especially challenging in forensic anthropology, resulting in the need for specialized methods of analysis. Due to the unique morphological characteristics of the frontal sinus, a positive identification can be made in cases of unknown human remains, even when remains are highly cremated or decomposed. This study retrospectively reviews 3D CBCT images of a total of 43 Caucasian patients between the ages of 20-38 from the Indiana University School of Dentistry to quantify frontal sinus differences between adult males and females and investigate the usefulness of frontal sinus morphology for forensic identification. Digit codes with six sections and eleven-digit numbers were created to classify each individual sinus. It was shown that 3D CBCT images of the frontal sinus could be used to make a positive forensic identification. Metric measurements displayed a high degree of variability between sinuses and no two digit codes were identical. However, it was also shown that there were almost no quantifiable and significant sexually dimorphic differences between male and female frontal sinuses. This study confirms that sex determination should not be a primary goal of frontal sinus analysis and highlights the importance of creating a standard method of frontal sinus evaluation based on metric measurements.
3

Constraints versus adaptations as contending evolutionary explanations of morphological structure : The giraffe (Giraffa Camelopardalis) head and neck as a heuristic model

Badlangana, Ludo Nlambiwa 01 December 2008 (has links)
The current study uses the head and neck of giraffe (Giraffa camelopardalis) as a model for tracking the course of evolutionary change. Gould (2002) has argued that there are three main avenues of evolutionary change that result in the genesis of new morphologies. These are phylogenetic constraints, structural or allometric scaling laws of form, and specific unique adaptations. It is well known that the unique characteristic of the giraffe is its extremely long neck and yet, it only has seven cervical vertebrae. To study the neck the vertebral body lengths of different aged giraffes were measured to determine the contribution of the cervical vertebrae to the total vertebral column. The vertebrae of several extant ungulates as well as those of fossil giraffids were used as a comparison with the giraffe. CT scans were used on several giraffe skulls to study the extent of the frontal sinus in the giraffe in an attempt to explain why the giraffe evolved such a large frontal sinus. The vertebral columns and skulls of several ungulates, including the okapi (Okapia johnstoni) were also used to compare with the results obtained from the giraffe. Immunohistochemistry was used to study the medulla and spinal cord sections of the giraffe to determine if the location and size of the nuclei remained unchanged to the basic ungulate or mammalian plan in spite of the unusually long neck, or if this long neck led to changes in the nuclei found in those regions. The results of these stains were all compared to the published literature available. Although more studies need to be conducted on other ungulates to conclusively determine why giraffe have evolved a long neck, overall the results showed that the anatomy giraffe head and neck remained true to the basic mammalian plan, with very little changing in terms of it morphology. The giraffe brain and spinal cord also resembled that of a typical ungulate. This leads to the conclusion that constraints and allometric scaling laws of form play a greater role than previously thought in the evolution of extreme morphologies.
4

Analysis of frontal sinus shape and volume variation between population affinity groups and biological sexes as seen on computed tomography scans

Shamlou, Austin 13 February 2022 (has links)
Frontal sinus variation has been used in forensic anthropology to aid in positive identification since the 1920s. As radiographic technology has evolved, so has the quality and quantity of data that radiologists and anthropologists can collect during an individual’s lifetime. This has led to new methodology when comparing antemortem and postmortem radiographic images. The current study aims to look at frontal sinus morphology and dimensional variations on computed tomography (CT) scans, as these are currently the most commonly collected images showing the frontal sinus in its entirety used in clinics in the United States. This study assessed 307 individuals for the morphological analysis and 325 individuals in the dimensional analysis. These individuals represented females and males from Asian, African, European, and Latin American derived groups. It is hypothesized that frontal sinus shape variations will cluster based on assigned sex and population affinities. Similarly, it is hypothesized that dimensional variation, specifically the maximum height, maximum width, and maximum depth, will show statistically significant clustering based on assigned sex and population affinities. The frontal sinus outlines from the CT images were transferred into SHAPE v1.3 in order to run an elliptical Fourier analysis. The dimensional data was measured directly from the images using a MicroDicom viewer. All of the statistical analyses, including Pearson’s Chi-squared and ANOVA tests, were run in R studio. Results indicated that morphologically there is no statistically significant clustering based on assigned sex or population affinity. However, there was statistically significant clustering dimensionally when tested against both assigned sex and population affinity using an ANOVA, indicating that the interactive effects of sexual dimorphism and population affinity influence the dimensions but not the shape of the frontal sinus. These results add to the foundational knowledge that practitioners have surrounding frontal sinus indicating that assigned sex and population affinity have impact on the approximate dimensions of this structure while these variables do not have a statistically significant effect on morphological variation. The results also speak to the idiosyncratic nature of the frontal sinus and bolster confidence using morphological variations as a mean to individuate.
5

Modern Technology Applied to Classic Technique: Virtual Surgical Planning for Design of Split-Calvarial Bone Graft for Frontal Reconstruction after Osteoma Resection in a Fifteen-Year-Old Male

Martin, Taylor, Johnson, Abbey, Condra, Alex, Horsley, Neil, Powers, Jeremy 25 April 2023 (has links)
Osteoid osteomas are common, painful, osteoblast tumors that frequently present in adolescents and young adults. Surgical management is indicated for cases with associated symptoms, such as headaches, dizziness, diplopia, proptosis, sinusitis, and facial deformity. The authors report a case of a 15-year-old male with an enlarging frontal sinus osteoma. Virtual surgical planning was utilized to design a KLS Martin Resorbable plate for the graft site, as well as a cutting guide for the graft procedure. A split-calvarial bone graft was used to reconstruct the central bony defect in the anterior table of the frontal sinus. Virtual surgical planning sessions were initiated with KLS Martin biomedical engineers to design a graft. Design cutting guides were created for frontal craniotomy, and an interlocking cutting guide was created for the split calvarial bone graft. The graft was harvested from the non-dominant right parietal hemisphere to best match the curvature of the frontal bone. Post-operatively, the patient has not had any complications to date. This procedure proves to be a valuable consideration for the surgical treatment of pediatric osteomas.
6

Tratamento de fraturas de seio frontal : estudo retrospectivo /

Rodrigues, Willian Caetano. January 2019 (has links)
Orientador: Marisa Aparecida Cabrini Gabrielli / Resumo: Complicações precoces e tardias de fraturas do seio frontal não são infrequentes, independentemente da técnica utilizada para tratamento. O objetivo do presente estudo foi avaliar o resultado do tratamento de fraturas da região frontal. Ao todo, 155 pacientes foram incluídos no estudo e avaliados por meio clinicamente e por meio de imagens de tomografia computadorizada. A média de idade foi de 32,86 anos e 88,30% eram do sexo masculino. As três principais etiologias do trauma foram acidente motorciclístico (23,87%), agressão física (20%) e acidente automobilístico (18,70%). O tempo de pós-operatório avaliado variou entre 6 meses a 27 anos (média: 7 anos e meio). Foram tratados por meio de reconstrução do seio frontal, 61,29%; obliteração, 6,45%; cranialização, 21,93% e tratamento não cirúrgico, 10,32%. Vinte e quatro por cento dos pacientes desenvolveram complicações pós-operatórias, tais como sinusite frontal, infecção do tecido mole, osteomielite, dor, mucocele, pneumoencéfalo e irregularidade óssea. As complicações diretamente relacionadas ao tipo de tratamento instituído foi a seguinte: reconstrução do seio frontal 6,3%; obliteração do seio frontal, 75%; cranialização: 2,94% e o tratamento não cirúrgico: 6,25%. Por meio dessa avaliação pode-se concluir que: (1) todas as técnicas de tratamento para fratura do seio frontal desenvolveram complicações pós-operatórias; (2) a obliteração do seio frontal apresentou prevalência para o desenvolvimento de complicações, devendo ser ... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
7

Utilização de imagens tridimensionais da cavidade sinusal frontal provenientes de tomografia computadorizada de feixe cônico para a identificação forense / Usage of tridimensional cone beam computed tomography imaging of the frontal sinus for human identifications in Forensic Scienses

Duailibi Neto, Eduardo Felippe 06 July 2016 (has links)
A unicidade da cavidade sinusal frontal é um importante fator para a identidade humana. O uso de registros de imagens dessa cavidade para a identificação forense é amplamente difundido, sendo uma metodologia secundária segundo a INTERPOL. Recentes avanços nas tecnologias de imagem permitiram o registro de imagens tridimensionais dessa cavidade. Nosso objetivo foi validar a metodologia proposta por Beaini et al. (2015), padronizando critérios para a obtenção de imagens tridimensionais da cavidade sinusal frontal com tomografia computadorizada de feixe cônico e avaliando a capacidade desses dados para a identificação humana. Para tanto, utilizamos um banco de imagens tomográficas de 200 pacientes randomizados e analisados por três observadores. As imagens foram exportadas em formato DICOM e submetidas a dois processos de segmentação distintos e sobreposição tridimensional. Realizou-se a metodologia descrita para estabelecer a identificação entre pacientes randomizados. Os resultados mostraram que há uma diferença significativa entre os processos de segmentação, sendo mais indicada a técnica de segmentação manual. A metodologia proposta por Beaini et al. (2015) foi validada e um total de 166 pacientes foram identificados. O volume da cavidade sinusal possui um elevado potencial de identificação com uma probabilidade aproximada de 85% para determinar o gênero dos indivíduos. / The uniqueness of the frontal sinus cavity is an important factor for establishing human identity. The usage of imaging records of this cavity for human identity is a secondary methodology according to the INTERPOL protocols. Recent advances in imaging technologies have enabled the three-dimensional imaging records of this cavity. Our goal was to validate the methodology proposed by Beaini et al. (2015), by developing standardized criteria for the use of cone beam computed tomography three-dimensional images of the front sinus and evaluating the ability of these data for human identification. The aim of this study was to investigate a total of 200 imaging records from randomized patients that were analyzed by three observers. Images were exported in DICOM format and underwent two distinct segmentation processes and a three-dimensional overlap. The Beaini et al. (2015) technique was applied to establish identification of the randomized patients. My results showed a significant difference between both segmentation processes, with manual segmentation showing the best results. Beaini et al. (2015) technique was validated and a total of 166 patients were identified. The volume of the sinus cavity has a high identification probability with a rough probability of 85% to determine the sex of individuals.
8

Estudo da identificação humana por meio da imaginologia dos seios frontais.

Almeida, Manuella Santos Carneiro 13 March 2012 (has links)
Made available in DSpace on 2015-05-14T12:56:00Z (GMT). No. of bitstreams: 1 Arquivototal.pdf: 2176646 bytes, checksum: 1bc824e5cb69d2fcdee753f80f5eb8df (MD5) Previous issue date: 2012-03-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to verify the applicability of parameters for human identification using the frontal sinuses, used by Tatlisumak et al. (2007), using axial and coronal reconstructions of CBCT and extraoral radiographs. From 58 dry disjointed skulls existing in the Management of Legal Medicine of Paraiba (PB-GEMOL) and University Center of Joao Pessoa, UNIPÊ, 26 skulls were selected. The acquisition of anteroposterior radiographs of the skull and lateral view were obtained through X-ray machine pan Rotograph Plus ® (Dabi Atlante Ltda., Ribeirão Preto, São Paulo, Brazil) and the CT at New iCAT device Generation ® (Imaging Sciences International, Pennsylvania, USA), adopting a specific methodology in order to standardize the tests to obtain and ensure the reproducibility of the study. The images were evaluated by two examiners calibrated in darkened environment and in two different times, with a minimum interval of one week. Assessments of axial and coronal reconstructions were performed with the aid of a 23 "program and iCat Vision (Imaging Sciences International, Pennsylvania, USA). For evaluation of extraoral radiographs were traced on paper made using ultrafan of 600 lux light box with mask and measurements with the aid of a high precision digital caliper Mitutoyo series 167 (Mitutoyo, Suzano, Brazil). Categorical variables were discrete and analyzed using the kappa test and continuous variables by Correlation Coefficient of Concordance Lin. Methods of analysis by cone beam CT and radiographic were mostly consistent, with only a few variables with unsatisfactory results (capd, and dpele dpontalt). For categorical variables and discrete intra-and inter-was great-perfect for both methods, as continuous variables showed moderate to excellent results. It is concluded that: the methodology proposed in this paper, using the parameters of the job Tatlisumak et al. (2007), are applicable and reliable in extraoral radiographs (X-rays AP and lateral radiographs of the skull face) and axial and coronal reconstructions of CBCT for human identification by frontal sinus, intra-and inter the parameters used by Tatlisumak et al. (2007) with CBCT imaging modality varies from substantial to excellent, and moderate to excellent radiographic images, there is a greater power of reproducibility and accuracy of the proposed method using the axial and coronal reconstructions of CBCT taking extraoral radiographs also reliability , the least consistent variable in the analysis by the images of CBCT is a measure capd (poor agreement), while the radiographic images and are dpele dpontalt (bad matches). This result indicates that these parameters are more susceptible to errors by evaluators, since it needs to use multiple points of reference for their measurements. / O objetivo neste estudo foi verificar a aplicabilidade de parâmetros de identificação humana por meio dos seios frontais, utilizados por Tatlisumak et al. (2007), com auxílio das reconstruções axiais e coronais de tomografia computadorizada de feixe cônico (TCFC) e radiografias extrabucais. De um universo de 58 crânios secos desarticulados existentes na Gerência Executiva de Medicina e Odontologia Legal da Paraíba (GEMOL-PB) e Centro Universitário de João Pessoa, Unipê, foram selecionados 26 crânios. As aquisições das imagens radiográficas póstero-anterior de crânio e lateral de face, foram obtidas por meio do aparelho de raios X panorâmico Rotograph Plus® (Dabi Atlante Ltda., Riberão Preto, São Paulo, Brasil) e as tomográficas, pelo aparelho iCAT New Generation® (Imaging Sciences International, Pennsylvania, EUA), adotando-se uma metodologia específica como forma de padronizar a obtenção dos exames e garantir a reprodutibilidade do estudo. As imagens foram avaliadas por dois examinadores previamente calibrados, em ambiente escurecido e em dois tempos distintos, com um intervalo mínimo de uma semana. As avaliações das reconstruções axiais e coronais foram realizadas com o auxílio de um monitor de 23 e programa iCat Vision (Imaging Sciences International, Pennsylvania, EUA). Para avaliação das imagens radiográficas extrabucais, foram realizados traçados em papel ultrafan utilizando negatoscópio de 600 lux com máscara e as mensurações com auxílio de um paquímetro digital de alta precisão Mitutoyo série 167 (Mitutoyo Sul Americana, Suzano, Brasil). As variáveis categóricas e discretas foram analisadas por meio do teste kappa e as variáveis contínuas pelo Coeficiente de Correlação de Concordância de Lin. Os métodos de análise pelas tomografias de feixe cônico e radiográficas foram em sua maioria concordantes, apresentando apenas algumas variáveis com resultados insatisfatórios (capd, dpele e dpontalt). Para as variáveis categóricas e discretas houve concordância intra e interexaminadores de ótima a perfeita em ambos os métodos, já as variáveis contínuas apresentaram resultados de moderada a excelente. Conclui-se que: a metodologia proposta no presente trabalho, utilizando os parâmetros do trabalho de Tatlisumak et al. (2007), são aplicáveis e confiáveis em radiografias extrabucais (radiografias PA de crânio e radiografias laterais de face) e reconstruções axiais e coronais de TCFC para a identificação humana pelos seios frontais; a concordância intra e interexaminador nos parâmetros utilizados por Tatlisumak et al. (2007) com a modalidade de imagem TCFC varia de boa a excelente; e de moderada a excelente nas imagens radiográficas; há um maior poder de reprodutibilidade e precisão do método proposto utilizando as reconstruções axiais e coronais de TCFC, tendo as radiografias extrabucais também confiabilidade; a variável menos concordante na análise pelas imagens de TCFC é a medida capd (concordância ruim); já pelas imagens radiográficas são dpele e dpontalt (concordâncias ruins). Tal resultado indica que estes parâmetros são mais passíveis de erros por parte dos avaliadores, uma vez que deve-se utilizar vários pontos de referência para suas mensurações.
9

Reconhecimento semi-automático de sinus frontais para identificação humana forense baseado na transformada imagem-floresta e no contexto da forma /

Falguera, Juan Rogelio. January 2008 (has links)
Orientador: Aparecido Nilceu Marana / Banca: Adilson Gonzaga / Banca: Humberto Ferasoli Filho / Resumo: Diversos métodos biométricos baseados em características físicas do corpo humano como impressão digital, face, íris e retina têm sido propostos para identificação humana. No entanto, para a identificação post-mortem, tais características biométricas podem não estar disponíveis. Nestes casos, partes do esqueleto do corpo humano podem ser utilizadas para identificação, tais como dentes, tórax, vértebras, ombros e os sinus frontais. Investigações anteriores mostraram, por meio de técnicas manuais para extração de características, que os padrões dos sinus frontais são altamente variáveis entre indivíduos distintos e únicos para cada indivíduo. Esta dissertação de mestrado tem por objetivo propor um método computacional para o reconhecimento de sinus frontais para identificação humana post-mortem em aplicações forenses. Para tanto, foram avaliados métodos de segmentação de imagens de radiografias anteroposteriores de sinus frontais. O método baseado na Transformada Imagem-Floresta demonstrou ser eficiente para segmentação dos sinus frontais das imagens de radiografias, exigindo mínima intervenção humana. Foram também investigadas e implementadas técnicas para extração de descritores geométricos e descritores baseados nas formas dos sinus frontais. Experimentos realizados em um banco de imagens contendo 90 radiografias anteroposteriores de 29 indivíduos mostraram que a técnica de extração de características baseada nos descritores de contexto da forma foi a mais eficaz, propiciando taxas de erro igual (EER) e de recuperações corretas (CRR) de 3,73% e 95,5%, respectivamente. Os resultados obtidos nos experimentos corroboram os encontrados na literatura sobre a individualidade dos sinus frontais e sua viabilidade em termos de precisão e usabilidade para a identificação humana post-mortem. Palavras-chave: Biometria, identificação... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Several methods based on Biometrics such as fingerprint, face, iris, and retina have been proposed for person identification. However, for postmortem identification such biometric measurements may not be available. In such cases, parts of the human skeleton can be used for identification, such as teeth, thorax, vertebrae, shoulders, and frontal sinus. Previous investigations showed, by means of manual features extraction techniques, that frontal sinus patterns are highly variable for distinctive individuals and unique for each one. The objective of this master thesis is to propose a computational method for frontal sinus recognition for postmortem human identification in forensic applications. In order to achieve this, methods for frontal sinus segmentation from anteroposterior radiographs were evaluated. The method based on Image-Foresting Transform has shown itself efficient in frontal sinus segmentation from radiograph images, demanding minimal human intervention. After the segmentation, techniques for extracting frontal sinus geometrical and shape-based descriptors were investigated and implemented. Experiments over a database containing 90 anteroposterior radiograph images from 29 individuals have shown that the features extraction techniques based on shape context descriptors were the most efficient, providing equal error (EER) and correct retrievals (CRR) rates of 3.73% and 95,5%, respectively. The results obtained in our experiments confirm the outcomes described in literature about the individuality of the frontal sinus and its feasibility in terms of precision and usability for postmortem human identification. Keywords: Biometrics, forensics human... (Complete abstract click electronic access below) / Mestre
10

Reconhecimento semi-automático de sinus frontais para identificação humana forense baseado na transformada imagem-floresta e no contexto da forma

Falguera, Juan Rogelio [UNESP] 23 June 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-23Bitstream added on 2014-06-13T19:18:04Z : No. of bitstreams: 1 falguera_jr_me_sjrp.pdf: 2234581 bytes, checksum: 19293ff7ecaf5caa8cf4417a59cb11fa (MD5) / Diversos métodos biométricos baseados em características físicas do corpo humano como impressão digital, face, íris e retina têm sido propostos para identificação humana. No entanto, para a identificação post-mortem, tais características biométricas podem não estar disponíveis. Nestes casos, partes do esqueleto do corpo humano podem ser utilizadas para identificação, tais como dentes, tórax, vértebras, ombros e os sinus frontais. Investigações anteriores mostraram, por meio de técnicas manuais para extração de características, que os padrões dos sinus frontais são altamente variáveis entre indivíduos distintos e únicos para cada indivíduo. Esta dissertação de mestrado tem por objetivo propor um método computacional para o reconhecimento de sinus frontais para identificação humana post-mortem em aplicações forenses. Para tanto, foram avaliados métodos de segmentação de imagens de radiografias anteroposteriores de sinus frontais. O método baseado na Transformada Imagem-Floresta demonstrou ser eficiente para segmentação dos sinus frontais das imagens de radiografias, exigindo mínima intervenção humana. Foram também investigadas e implementadas técnicas para extração de descritores geométricos e descritores baseados nas formas dos sinus frontais. Experimentos realizados em um banco de imagens contendo 90 radiografias anteroposteriores de 29 indivíduos mostraram que a técnica de extração de características baseada nos descritores de contexto da forma foi a mais eficaz, propiciando taxas de erro igual (EER) e de recuperações corretas (CRR) de 3,73% e 95,5%, respectivamente. Os resultados obtidos nos experimentos corroboram os encontrados na literatura sobre a individualidade dos sinus frontais e sua viabilidade em termos de precisão e usabilidade para a identificação humana post-mortem. Palavras-chave: Biometria, identificação... / Several methods based on Biometrics such as fingerprint, face, iris, and retina have been proposed for person identification. However, for postmortem identification such biometric measurements may not be available. In such cases, parts of the human skeleton can be used for identification, such as teeth, thorax, vertebrae, shoulders, and frontal sinus. Previous investigations showed, by means of manual features extraction techniques, that frontal sinus patterns are highly variable for distinctive individuals and unique for each one. The objective of this master thesis is to propose a computational method for frontal sinus recognition for postmortem human identification in forensic applications. In order to achieve this, methods for frontal sinus segmentation from anteroposterior radiographs were evaluated. The method based on Image-Foresting Transform has shown itself efficient in frontal sinus segmentation from radiograph images, demanding minimal human intervention. After the segmentation, techniques for extracting frontal sinus geometrical and shape-based descriptors were investigated and implemented. Experiments over a database containing 90 anteroposterior radiograph images from 29 individuals have shown that the features extraction techniques based on shape context descriptors were the most efficient, providing equal error (EER) and correct retrievals (CRR) rates of 3.73% and 95,5%, respectively. The results obtained in our experiments confirm the outcomes described in literature about the individuality of the frontal sinus and its feasibility in terms of precision and usability for postmortem human identification. Keywords: Biometrics, forensics human... (Complete abstract click electronic access below)

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