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Sundén, Pikner Solweig. "Radiographic follow-up analysis of Brånemark® dental implants /." Göteborg : Department of Oral and Maxillofacial Radiology, Institute of Odontology, University of Gothenburg, Folktandvården, Postgraduate Dental Education Center, 2008. http://hdl.handle.net/2077/10124.
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Hall, Nathan E. "A Radiographic Analysis of Variance in Lower Incisor Enamel Thickness." VCU Scholars Compass, 2005. http://scholarscompass.vcu.edu/etd/887.
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The purpose of this study was to help predict the enamel thickness of mandibular incisors. At least two direct digital periapical radiographs were made for each of the 80 subjects. Radiographs were scaled to control for magnification errors using dental study models and computer software. Mesiodistal incisor width and mesial and distal enamel thicknesses were measured. Lateral incisors were determined to be wider than central incisors and distal enamel thicknesses were larger than mesial enamel thicknesses on average. The African American group demonstrated wider incisors and enamel thicknesses than the Caucasian group on average. Enamel thickness positively correlated with tooth width for all incisors. No statistically significant differences were detected between male and female groups. Some conclusions relating to enamel thickness can be made based on race, incisor position, and incisor width, but correlations were not considered strong enough to accurately determine enamel width, without the aid of radiographs.
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Mistry, Sapan. "Radiographic analysis of femoroacetabular impingement with Hip²Norm : reliable and validated /." [S.l.] : [s.n.], 2008. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000279111.
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Batra, Preeti. "Analysis of Radiographic Changes Associated with the Periradicular Diagnosis of Symptomatic Apical Periodontitis." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4141.
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Symptomatic apical periodontitis (SAP) is indicative of inflammation of the periodontal ligament. It may or may not be accompanied by radiographic changes and may occur with vital or necrotic pulpal diagnosis. Purpose of this study was to analyze clinical and radiographic presentations of SAP in a retrospective electronic dental chart and digital radiograph review utilizing the endodontic diagnostic template note of predoctoral dental school patients presenting with SAP. The aim was to determine prevalence of periapical radiolucencies (PARLs) in SAP, association of SAP to pulpal diagnosis, and define associated radiographic changes. Most prevalent pulpal diagnosis with SAP was symptomatic irreversible pulpitis (44%). A tooth presenting with SAP was more likely to have an intact lamina dura, but presented with a PARL 38% of the time. When a PARL was present the most common pulpal diagnosis was pulp necrosis however, 24.5% of teeth presented with a vital pulp diagnosis and lesions <2mm.
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Taranto, Julie. "Analysis of dynamic angle of gait and radiographic features in subjects with hallux valgus." University of Western Australia. School of Surgery and Pathology, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0049.
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[Truncated abstract] Hallux valgus (HV) is one of the most common foot deformities encountered in clinical practice. This complex deformity primarily affects the first metatarsophalangeal joint (MPJ), leading to altered foot structure and function. By virtue of the lateral displacement of the hallux on the first metatarsal, HV has the potential to influence adjacent joints of the foot. In doing so, function of the foot may be altered, and clinically this may result in abduction of the foot during the stance phase of gait. However the relationship between an abducted angle of gait (AOG) and HV has never been substantially examined. The purpose of this study is to investigate the relationship between HV and AOG, and determine if specific radiographic features are associated with the deformity or with a particular AOG. Such information would assist in understanding aetiological factors and the effects of intervention to treat the deformity ... Length and elevation of the first metatarsal were associated in subjects with HV, implying that length of the metatarsal may be related to whether or not it becomes elevated (R: 0.50, CI: 0.21, 0.71, P< 0.05). Similarly, an association was found between length of the first metatarsal and the amount of first MPJ dorsiflexion, suggesting perhaps length of the metatarsal has implications for first MPJ range of motion (R: -0.37, CI: -0.62, -0.04, P<0.05). However the amount of first MPJ dorsiflexion did not influence the AOG in HV subjects when compared to the control group. First MPJ dorsiflexion was also associated with the first intermetatarsal angle. Interestingly, the HV group alone did not show an association between the hallux abductus angle and the first intermetatarsal angle. The findings of this study are contrary to those suspected in clinical practice and alluded to in the literature. Despite the documented support for the biomechanical causes of HV, an abducted AOG was not significantly different in HV subjects when compared to controls. Possible explanations may have related to limitations of the present study including the size and gender demographics of the sample population, and greater variability in normal AOG ranges than reported in the literature. The present study indicated a possible need to gather information regarding foot dominance and leg length; factors extrinsic to the foot capable of influencing transverse plane orientation of the foot; and, the influence of symptoms and subsequent compensatory mechanisms adopted during gait.
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Proudman, Timothy William. "Crouzon syndrome : a clinical and three dimensional radiographic analysis of craniofacial morphology and surgery /." Title page, contents and summary only, 1995. http://web4.library.adelaide.edu.au/theses/09MS/09msp968.pdf.
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Abofatira, Mohamed Farag. "A radiographic analysis of the anterior palate as a donor site for bone harvesting." University of the Western Cape, 2015. http://hdl.handle.net/11394/5040.
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Magister Scientiae Dentium - MSc(Dent)<br>Autologous bone grafting in conjunction with dental implant therapy is a well-accepted procedure in oral and maxillofacial rehabilitation. A variety of intraoral donor sites, such as the mandibular symphysis, the mandibular ramus and the maxillary tuberosity have been used in oral and maxillofacial reconstruction. However these sites are associated with complications. In order to reduce these complications, the anterior palate has been proposed as a potential donor site. However, the scientific literature in this regard is sparse, and larger studies are required to investigate the clinical potential of this proposed site. Aim: To determine the volume and density of available bone in the anterior palate that may be used for bone harvesting using cone-beam computed tomography (CBCT) in a select South African population. Materials and methods: One hundred previously acquired CBCT scans taken at the Diagnostic and Radiology Department of Tygerberg Oral Health Centre were analyzed for the required data. These were all acquired from a single CBCT machine (Newtom VGI®, Verona, Italy). The study sample included 52 females and 48 males ranging from ages 20 years to 80 years. The CBCT scans were divided into 3 different age groups. The first age group was between the ages of 20 and 39 years, the second age group was from 40 to 59 years and the third age group was ≥ 60 years. The volume and density of the anterior palate of the different age groups were analyzed using specific criterion. CBCT specific software (Simplant Pro Crystal®) Dentsply implants, Mannheim, Germany was used to standardize the data collection. All data was stored in a Microsoft Excel spreadsheet (Microsoft Corporation, Washington, USA). Results: The mean volume of the anterior palate in this study was 2.11 ± 0.55 cm3, with a minimum volume of 1.04 cm3 and a maximum volume of 3.82 cm3. There was no significant difference in the volume and density of the anterior palate between different age groups and no significant difference in the volume between males and females (p value = 0.227). Conclusions: The anterior palate affords a considerable amount of bone volume which is similar or even more than other intraoral donor sites. The anterior palate is a potential donor site for bone harvesting and CBCT may be regarded as an ideal tool to analyze the amount of bone available for harvesting.
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Bowman, Scott. "Decision making and judgement in radiographic and sonographic practice : an investigation using decision analysis." Thesis, Open University, 2000. http://oro.open.ac.uk/54564/.
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This is a study into decision making and judgement in the context of radiography. The early part of the study investigated the nature and scope of decisions and judgements made in general radiography and sonography, while the later part focused on the decisions and judgements made by sonographers when breaking bad news to patients. The study is located in a broad interpretative framework, it used an adapted form of phenomenological methodology. A survey and an observational study were used to collect data. In-depth interviews were conducted which used decision analysis (a tool normally used as a decision aid) to elicit participants perceptions and experiences of decision making and judgement. Decision analysis was used in three different ways to collect data. The technique was found to be particularly useful in enabling participants to reflect on their intuitive processes and hence make them overt. The data collected during the observational phase of the study was used to formulate a classification of radiographic decision making and judgement. The study found that the predominant style of decision making and judgement in radiography is intuitive with some evidence of peer-aided decision making and judgement. There is little evidence that the participants use systems aided approaches. Participants found the process of decision analysis interesting but could not relate its use to their own professional practice other than as an educational or de-briefing tool. In sonography it was found that participants had an over-confidence in their diagnostic abilities which influenced their decision making. Sonographers were also found to produce information based on experience, when this information was absent from the decision making scenario provided. On the whole the participants in this study had given little thought to the process of decision making and judgement and the impact of factors such as base rates.
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Tehrany, Arya M. Rivera Eric M. "Outcome study of gutta-percha and Resilon filled root canals a radiographic and clinical analysis /." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2009. http://dc.lib.unc.edu/u?/etd,2837.
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Thesis (M.S.)--University of North Carolina at Chapel Hill, 2009.<br>Title from electronic title page (viewed Jun. 4, 2010). "... in partial fulfillment of the requirements for the degree of Master of Science in the Department of Endodontics, School of Dentistry." Discipline: Endodontics; Department/School: Dentistry.
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Lawrence, Herenia Procopio. "Computer-assisted radiographic analysis of caries progression in fluoridated and fluoride-deficient areas in Brazil." Thesis, Queen Mary, University of London, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341124.
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Ivanauskaitė, Deimantė. "Alveolar bone loss in radiographic modalities for diagnosis of periodontal disease." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110621_164329-13939.
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Radiographic modalities are used in addition to clinical methods to gain information about the patients. In the examination of the periodontium, which is comprised of the gingiva, alveolar bone, periodontal ligament, and cementum, the radiographic examination plays an integral role for diagnosis of periodontal disease. The diagnosis periodontitis is based on a finding of alveolar bone loss. Changes of the alveolar bone can be assessed by different radiographic modalities, such as intraoral radiography (bitewing and periapical radiography) and panoramic radiography. Analysis of alveolar bone loss (alveolar bone level, detection of vertical bone defect and furcation involvement) in radiographic modalities and a systematic review could be helpful to suggest the more applicable radiographic methods for diagnosis of periodontal disease. The purpose of the present study was to examine diagnostic properties of panoramic radiography for the assessment of alveolar bone loss for the diagnosis of periodontal diseases as compare to posterior bitewing radiography. For 96 patients panoramic and posterior bitewing radiographs were performed and results of analysis of visibility of radiographic images and assessment of alveolar bone loss were compared. Also, the systematic review on diagnostic properties of panoramic radiography in the assessment of alveolar bone loss was performed. Based on the results of this study, recommendations for clinical practice and for research were proposed.<br>Rentgeniniai tyrimo metodai taikomi, kad būtų papildyti klinikinio tyrimo duomenys. Tiriant periodontą, kurį sudaro dantenos, dantinė atauga, periodonto raiščiai ir cementas, rentgeninis tyrimas svarbus diagnozuojant periodonto ligas, nes jo metu nustatomi dantinės ataugos pokyčiai. Dantinės ataugos pokyčiams vertinti daromos rentgeno nuotraukos taikant vidinių burnos rentgeno nuotraukų darymo metodus, t. y. kandimo ar dantų šaknų rentgeno nuotraukų darymo metodus, ir išorinės burnos rentgeno nuotraukos darymo metodą, t. y. panoraminės rentgeno nuotraukos darymo metodą. Atlikus dantinės ataugos pokyčių (kaulo lygio arba rezorbcijos, kaulo defekto ir tarpšaknio kaulo pažeidimų) analizę, taikant rentgeninius metodus, ir padarius sisteminę literatūros apžvalgą, galima būtų pasiūlyti tinkamiausią rentgeno metodą periodonto ligoms diagnozuoti.
Šio darbo tikslas – ištirti ir palyginti panoraminės rentgeno nuotraukos ir kaplių bei krūminių dantų rentgeno nuotraukų darymo metodų diagnostikos ypatybes vertinant dantinės ataugos pokyčius periodonto ligoms diagnozuoti.
Kiekvienam, iš 96 pacientų įtrauktų į tyrimą, buvo padaryta panoraminė rentgeno nuotrauka ir kaplių bei krūminių dantų kandimo rentgeno nuotraukos. Atlikta dantinės ataugos rentgeno atvaizdo vizualioji kokybė analizė ir vertinimai skirtingose rentgeno nuotraukose bei palyginti rezultatai. Padaryta sisteminė literatūros apžvalga apie panoraminės rentgeno nuotraukos vertę diagnozuojant periodonto ligas.
Pagal šio tyrimo... [toliau žr. visą tekstą]
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Nilsson, Kjell G. "Kinematics and fixation of total knee arthroplasties : a clinical, radiographic, scintimetric, and roentgen stereophotogrammetric evaluation." Doctoral thesis, Umeå universitet, Ortopedi, 1992. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-100552.
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Aseptic loosening of the tibial component is an important cause of failure after total knee arthroplasty. Bone destruction often claimed to be caused by the cement makes the revision difficult. In order to treat younger patients, uncemented fixation has been introduced, but the etiology to loosening is multifactorial and only partly known. Early detection of implant migration facilitates research in this field but is difficult using conventional techniques. In this study modified versions of roentgen stereophotogrammetric analysis (RSA) were developed to obtain accurate and standardized evaluations facilitating comparison between prosthetic designs. The method was used to record the efficacy of cemented and uncemented fixation of different designs of the tibial component, to determine the accuracy of scintimetry in the detection of early aseptic loosening, and to analyse the in vivo kinematics of knee arthroplasties with different design and stability between the joint surfaces. Forty-three arthroplasties with comparatively high inherent stability of the joint surfaces were randomized to cemented or uncemented fixation of the tibial component. In all groups micromovements were rather large, but with no differences between the cemented and uncemented components. The preoperative diagnosis (arthrosis OA, n=25; rheumatoid arthritis RA, n=18) did not influence the magnitude of micromotion. 20 arthroplasties with the same design as above but equipped with an intramedullary stem, were randomized to cemented or uncemented fixation in patients with RA. Cement improved the fixation. Uncemented stemmed components displayed micromovements seemingly larger than unstemmed ones. 34 arthroplasties with an unconstrained design of the joint area and fixed to the tibia with four pegs were randomized to cemented or uncemented fixation in patients with OA. When used uncemented 4 screws were added. Compared with previously investigated designs small micromotions were recorded, and especially in the cemented cases. Uncemented components with thin polyethylene inserts displayed larger initial micromotions. The preoperative deformity influenced the direction of the micromotion. 33 knees were followed prospectively with RSA and scintimetry to evaluate any correlation between these methods. Low activity under the tibial component at 2 years implied prosthetic stability, whereas high activity indicated instability or high bone remodelling caused by the preoperative malalignment. The in vivo kinematics in three different designs of knee arthroplasties were analyzed during active flexion and extension without weight-bearing. Each type of prosthesis displayed design-specific abnormalities when compared with a normal material. Pronounced posterior tibial translations were recorded during flexion regardless whether the posterior cruciate ligament had been sacrificed or not. Data from the kinematic and the fixation studies suggest that movements restricted by the design of the joint area are transmitted to the bony interface with design-specific micromotions as the result. Analysis of knee joint kinematics during extension and weight-bearing revealed small alterations compared with non-weight-bearing. Evaluation of the three-dimensional movements in terms of helical axis rotations and translations confirmed the constrained or unconstrained in vivo behaviour of the designs under study. This analysis also facilitated the interpretation of the kinematic behaviour of the prosthetic knees and may be of value in the evaluation of new designs.<br><p>Diss. (sammanfattning) Umeå : Umeå universitet, 1992, härtill 7 uppsatser.</p><br>digitalisering@umu
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Wright, Jennifer Lynne. "The role of discourse in the constitution of radiographic knowledge : a critical realist account /." Thesis, Rhodes University, 2008. http://eprints.ru.ac.za/1532/.
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Thesis (Ph.D. (Education)) - Rhodes University, 2008.<br>Title on the programme: The role of language in the constitution of radiographic knowledge : a critical realistic account. Includes bibliographical references (leaves 271-280).
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Leyland, Kirsten. "The association between radiographic knee osteoarthritis and pain: an epidemiological analysis of a twenty-year community-based cohort." Thesis, University of Oxford, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601129.
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Background: Knee osteoarthrit is (OA) is one of the leading musculoskeletal burdens in the world, causing both structural damage and pain to the joint. Radiographs are the most common imaging method for diagnosing OA, however the relationship between radiographic changes (ROA) and symptoms is not well understood. This thesis will establish the natura l history of twenty-year ROA, compare diagnostic methods of ROA assessment, evaluate the cross-sectional relationship between ROA and pain, and will determine the long-term predictive validity of features of ROA with future knee rep lacements. Methods: Data from the Chingford women's study, a twenty-year prospective UK-based cohort was used for the analysis. Risk factors included atlas-based ROA scoring methods and quantitative joint space width, which were analysed against pain and TKR outcome measures. A novel method for assessing joint space on low-contrast x-rays was developed which had high reproducibility and validity. ii
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Al-Jandan, Badr. "The efficacy of biodegradable mesh as a fixation device for support of autogenous onlay bone grafts : a radiographic and histomorphometric analysis." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112373.
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Objective. The objective of this study is to test the efficacy of the biodegradable mesh as an alternative fixation device to the titanium mesh for support of onlay particulate, bone and cancellous, marrow (PBCM) grafts. Two parameters were evaluated: (1) Bone graft volume maintenance; and (2) Calcified tissue surface area and distribution. Methods. 12 New Zealand white rabbits were used and divided equally into two groups. In both groups, endochondral, cancellous bone graft was harvested from the anterior ilium. The bone graft was then compressed and placed as an onlay onto the lateral aspect of the mandible using two chambers for each animal. In the control group, the chambers were made of titanium, however in the test group the chambers were made of poly L-lactide, polyglycolide and trimethylene carbonate mesh (Inion GTR(TM) Finland), and thereafter the chambers were fixed to the mandible. The animals were then sacrificed after eight weeks postoperatively, and then Micro-CT imaging was performed for the entire sample in order to determine the total volume of calcified tissue present under each chamber. In addition, Histologic sections were obtained from each chamber, and thereafter stained using Toluidine blue and Von Kossa for the purpose of histomorphometric analysis in order to determine the calcified tissue surface area. Results. When comparing the data from both the titanium (Ti) and the biodegradable mesh (PLA) groups, Micro CT analysis showed no significant statistical difference (P-value = 0.546) with regard to the percentage of bone found under the chambers (Ti 15.0% and PLA 13.83%). Interestingly, neither did the histomorphometric analysis show any significant statistical deference (P-value = 0.8272) with regard to the percentage of calcified tissue surface area (Ti 16.86% and PLA 16.17%). Moreover, this calcified tissue was also found to be evenly distributed in both groups. Conclusion. Biodegradable mesh made of poly L-lactic and polyglycolic acid copolymers appears to be an appropriate alternative to the Ti mesh for support of PBCM bone grafts. However, further clinical trails should be conducted to confirm these findings.
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Ji, Xiang. "The association of variations in hip and pelvic geometry with pregnancy-related sacroiliac joint pain based on a longitudinal analysis." Kyoto University, 2019. http://hdl.handle.net/2433/242658.
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Nabee, Mahomed Ridhwaan Goolam. "Demographic profile, clinical data and radiographic analysis of patients for third molar surgery under general anaesthesia at the Faculty of Dentistry at the University of the Western Cape." University of the Western Cape, 2018. http://hdl.handle.net/11394/6504.
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Magister Scientiae Dentium - MSc(Dent)<br>Aim
To analyze the demographic profile, clinical data and radiographs of patients who had third molar
surgery under general anaesthesia at the Faculty of Dentistry at the University of the Western
Cape over a 10 year period.
Introduction
Minor oral surgical procedures are carried out by Maxillofacial and Oral Surgeons daily. The
surgical removal of third molars is a large part of Minor Oral Surgery which is common
throughout the world. The general impression of third molar surgery performed by experienced
professionals is the ease of the operation, however no-matter how experienced one may be, a
simple procedure should never be underestimated (Carvalho and Do Egito Vasconselos, 2011).
New surgical techniques, as well as extensive training, skill and experience have led to the
evolution of oral surgery and allowed this procedure to be carried out in a less traumatic manner.
Certain factors precipitate third molar surgery to be performed in theatre as opposed to the dental
clinic setting. These factors will be discussed in this research report.
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Brown, Anna Laura. "Bismuth Nanoparticles as Medical X-ray Contrast Agents: Synthesis, Characterization and Applications." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1523.
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Bismuth based nanomaterials have recently attracted attention as heavy element X-ray contrast agents because of the high atomic number and predicted biological compatibility of bismuth. Nanoparticle X-ray contrast agents may enable a number of novel medical imaging applications, including blood pool and site-directed imaging. However these hypothetical applications are hindered by lack of suitable synthetic methods for production of imaging agents. This dissertation describes synthesis of a novel class of bismuth nanoparticles that are aqueously stabilized using poly and monosaccharides. These particles are synthesized using highly biologically compatible reagents and are oxidatively stable in water and in moderately basic buffered solutions. Bismuth nanoparticles stabilized by the polysaccharide dextran have a large hydrodynamic radius and a relatively small bismuth nanocrystal core (4% bismuth by volume.) Glucose-capped particles have a much higher ratio of bismuth by volume (>60%), and experimental CT scans of these particle solutions demonstrate higher X-ray contrast versus a current clinically used radiocontrast agent. Additional syntheses of hydrophobic organoamine-capped bismuth nanoparticles by reduction of an iodobismuth cluster, and development of other X-ray contrast materials, such as a radiopaque surgical sponge marker and ink, using bismuth micoparticles produced by a top-down ball milling method, are also described.
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Knuppel, Julie M. "Correlation of Neurologic Status As Evaluated By Neurologic Examination And Brainstem Auditory Evoked Response Test With Computed Tomographic And Radiographic Morphometric Analysis Of The Caudal Skull In Cavalier King Charles Spaniels." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243866074.
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Hayek, Jorge Elie. ""Avaliação da densidade ótica perimplantar cervical em controle longitudinal de implantes com função oclusal imediata em maxila"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/23/23139/tde-11112005-115646/.
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A proposta neste estudo foi avaliar as alterações da densidade ótica do osso alveolar perimplantar cervical em controle longitudinal, por meio de radiografias periapicais digitalizadas de dez pacientes, nos quais foram instalados seis implantes na maxila submetidos à função oclusal imediata, mediante a instalação de uma prótese fixa 24 horas após a cirurgia. Todos os pacientes foram avaliados clinicamente, com exames da análise da freqüência de ressonância, além de controle radiográfico. Foi utilizada a técnica radiográfica intrabucal do parale lismo, com cone longo, sendo que o feixe de raios X incidiu perpendicularmente ao longo eixo do implante. Os controles radiográficos foram realizados na instalação da prótese, após 6 meses e após 12 meses. As radiografias obtidas foram então capturadas por uma câmera de vídeo (preto e branco) por meio de um microscópio ótico (40 vezes de aumento). Devido à ampliação utilizada, os implantes tiveram suas imagens digitalizadas em 2 etapas (metade direita e metade esquerda), sendo consideradas como amostras independentes. Após a sobreposição de um gabarito sobre a imagem, com a finalidade padronizar as áreas a serem estudadas, foram analisadas as densidades óticas na área de interesse osso + implante e na área de controle implante (onde não é esperada alteração) por meio do software ImageLab. Para a correção de possíveis variações na densidade da radiografia e projeção geométrica oriundas da metodologia empregada, foi utilizada uma equação matemática para validar a análise dos dados obtidos. Os resultados mostraram que ocorreu variação percentual da densidade ótica na área de interesse (osso + implante) nos primeiros seis meses (T2) com diminuição de aproximadamente 5% para o lado direito e diminuição de aproximadamente 6% para o lado esquerdo em relação às radiografias iniciais (T1) e após doze meses, a diminuição da densidade ótica estabilizou-se, não sendo encontradas alterações estatisticamente significantes em relação ao período correspondente entre T2 (seis meses) e T3 (doze meses). Os resultados da análise digital das radiografias periapicais demonstraram coincidência com os resultados da análise da freqüência de ressonância e exame clínico dos implantes e demonstraram um aspecto compatível com o sucesso dos implantes osteointegrados com função imediata na maxila.<br>The aim in this study was the evaluation of the variations of the perimplantar optical bone density at the cervical region in a longitudinal control, by the use of digitized radiographs of ten patients, who received six implants installed in the maxilla and submitted to immediate occlusion function, through fixed prosthesis installed 24 hours after the surgery. All the patients were observed in clinical control, with resonance frequency analysis and also radiographic control. It was performed a intraoral radiograph using the paralleling technique, with the long cone and the beam of x-ray aimed perpendicular to the long axis of the implant. The radiographic controls were done at the time of the installation of the prosthesis, after six months and after twelve months after the first control. The obtained radiographs were captured by a black and white video camera by an optical microscope (40 times of magnification). Due to the utilized magnification, the implants have their images digitized in two steps: half right and half left, and they were considered as independent samples. After the superimposition of a standardized pattern, to help the standardization of the areas of the study, it was analyzed the optical density at the areas of interest bone + implant and at areas of control bone (where it is not hope changes) through the software ImageLab. To correct possible variations of the effect of the absence of standardization of the geometric projection and the radiographic density, it was realized a mathematic equation and it was obtained a correction factor of density in order to compensate. The results sho wed that there were percentage variation of the optical density at the area of interest (bone + implant) at six months (T2) showed a decreased of about 5% for the right side and showed a decreased of about 6% for the left side when analyzed the first control and after twelve months no significant statistical difference was observed between the T2 period (six months) and T3 period (twelve months). The results of digital analysis from the intraoral radiographs showed as the same as the results of resonance frequency analysis and the clinic examination of the implants and showed a success of implants installed in the maxilla with immediate occlusion function.
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Bittar-Cortez, Juliana Araujo. "Radiografia digital e a tecnica de subtração no monitoramento da desmineralização e remineralização do esmalte dentario." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288985.
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Orientador: Francisco Haiter Neto<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba<br>Made available in DSpace on 2018-08-10T07:50:35Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008<br>Resumo: O objetivo deste estudo in vitro foi comparar dois protocolos de remineralização em lesões de cárie no esmalte dentário, avaliados por meio de análises de cálcio (Ca) e fósforo (Pi), dureza do esmalte, microscopia de luz polarizada e subtração radiográfica digital (SRD); avaliar a viabilidade da utilização de dois diferentes sistemas de radiografias digitais, placa PSP (photostimulable storage phosphor) e sensor CMOS (complementary metal oxide semicondutor), no diagnóstico de desmineralizações, e a acurácia das radiografias digitais convencionais (RDC) e três métodos de SRD (linear, avançada e logarítmica) no diagnóstico de mudanças minerais; e comparar o ruído e reprodutibilidade das imagens de SRD lineares e logarítmicas produzidas a partir de dois sistemas de radiografias digitais. Para isso, lesões de cárie artificiais foram criadas em 100 superfícies proximais de dentes hígidos. Vinte dentes foram mantidos como controle e oitenta foram submetidos a dois diferentes protocolos de remineralização em 4 e 8 semanas, com a contínua imersão em saliva artificial e um tratamento adicional com flúor. Radiografias digitais foram realizadas antes e depois dos protocolos de remineralização. Cinco examinadores avaliaram a desmineralização e as mudanças minerais nas RDC, dispostas lado a lado, e três métodos da SRD. As análises de Ca / Pi e a colocação dos dentes na solução remineralizante foram considerados como padrão ouro. A média dos tons de cinza e o desvio padrão (DP) no histograma foram também mensurados. As concentrações de Ca e Pi na saliva artificial após os tratamentos foram significativamente menores do que a solução original (p<0,05); e por meio da SRD foi possível verificar diferenças entre as imagens. Entretanto, o teste de dureza e a microscopia de luz polarizada não detectaram nenhuma alteração. O sistema CMOS foi significativamente mais acurado do que a sistema PSP no diagnóstico da desmineralização e mudanças minerais, assim como a SRD linear no diagnóstico de mudanças minerais. Também foram estatisticamente diferentes os valores da média dos níveis de cinza e do DP entre os dois sistemas. Foi concluído que (a) o tratamento adicional de flúor promoveu valores maiores de ganho mineral; (b) a análise de Ca / Pi na saliva artificial foi o método mais sensível na avaliação de alteração mineral; (c) a imagem de SRD linear é um método válido na detecção do aumento de intensidade, como sinal de ganho mineral; e (d) as imagens de SRD utilizando as placas PSP tiveram um menor ruído do que nas imagens geradas pelo sensor CMOS<br>Abstract: The aim of this in vitro study was to compare two remineralization protocols of artificial carious lesions in enamel, evaluated by Calcium (Ca) and Phosphorus (Pi) analysis, cross-section hardness test, polarized light microscopy and digital subtraction images (DSR); to assess the feasibility of using two different systems of digital radiography, photostimulable storage phosphor (PSP) plate and complementary metal oxide semiconductor (CMOS) sensor on the demineralization diagnosis, and the accuracy of digital conventional radiographs (DCR) and three methods of DSI (linear, advanced and logarithmic) on mineral changes diagnosis; and, to compare noise and reproducibility in linear and logarithmic DSI produced from two digital radiography systems. Artificial caries-like lesions on 100 approximal surfaces of sound teeth were produced. Twenty teeth were kept as control and eighty teeth were subjected to two different remineralization protocols for 4 and 8 weeks, with continuous immersion in artificial saliva, and additional fluoride treatment. Digital radiographs were taken before and after the remineralization protocols. Five examiners assessed demineralization and mineral changes on DCR, placed side by side, and three methods of DSI. Ca / Pi analysis and the placement of the teeth on the remineralization solution was the gold standard. The mean shades of gray and the standard deviation (SD) of the histogram were also assessed. The concentrations of Ca and Pi in the artificial saliva after the treatments were significantly lower than the original solution (p<0.05); and DSR showed differences between the images. However, the Hardness test and polarized light microscopy did not detect any changes. CMOS system was significantly more accurate than PSP system on demineralization and mineral changes diagnosis, and also linear DSR on mineral changes diagnosis. It was also statistically significant different the values of mean shades of gray and SD between both systems. It was concluded that (a) the additional Fluoride treatment provided higher values of mineral gained; (b) Ca / Pi analysis in the artificial saliva were the most sensitive method of mineral change evaluation; (c) linear DSI is a valuable method to disclose an intensity increase, as a sign of mineral gained; and (d) DSR images created from PSP plates had less noise than images produced from CMOS sensor<br>Doutorado<br>Radiologia Odontologica<br>Doutor em Radiologia Odontológica
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Rabenius, Michaela. "Deep Learning-based Lung Triage for Streamlining the Workflow of Radiologists." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-160537.
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The usage of deep learning algorithms such as Convolutional Neural Networks within the field of medical imaging has grown in popularity over the past few years. In particular, these types of algorithms have been used to detect abnormalities in chest x-rays, one of the most commonly performed type of radiographic examination. To try and improve the workflow of radiologists, this thesis investigated the possibility of using convolutional neural networks to create a lung triage to sort a bulk of chest x-ray images based on a degree of disease, where sick lungs should be prioritized before healthy lungs. The results from using a binary relevance approach to train multiple classifiers for different observations commonly found in chest x-rays shows that several models fail to learn how to classify x-ray images, most likely due to insufficient and/or imbalanced data. Using a binary relevance approach to create a triage is feasible but inflexible due to having to handle multiple models simultaneously. In future work it would therefore be interesting to further investigate other approaches, such as a single binary classification model or a multi-label classification model.
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Janvier, Thomas. "Caractérisation de la gonarthrose sur radiographie X par analyse de la texture de l’os trabéculaire." Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2032/document.
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Cette thèse présente l’apport d’une analyse fractale de la texture de l’os trabéculaire sur des clichés de radiographie du genou pour la caractérisation de la gonarthrose. Dans un premier temps cette analyse de texture a été confrontée aux méthodes actuelles de suivi de la pathologie afin de valider leur intérêt dans le suivi clinique des patients. Un second temps a été consacré à la prédiction de l’initiation de la pathologie où aucun marqueur ne fait référence. L’analyse de texture a été menée en utilisant des approches fractales permettant de s’affranchir des problèmes de variation d’acquisition entre différents centres cliniques tout en comparant différentes méthodes de calcul. La texture osseuse trabéculaire a été analysée à différentes plages d’échelle afin de caractériser les mécanismes sous-jacents de modification de la microarchitecture osseuse induits par la gonarthrose. Nous avons pu mettre en évidence l’intérêt prédictif de cette analyse peu coûteuse et largement accessible dans le cadre aussi bien de l’initiation que de la progression de l’arthrose du genou<br>This thesis presents the contribution of the trabecluar bone texture fractal analysis on knee radiographs for the knee osteoarthritis characterization. Firstly, this texture analysis was confronted to the actual methods of the pathology clinical monitoring in order to validate their interest in the patients monitoring. Secondly, the prediction of the knee osteoarthritis initiation was investigated, domain in which there are still no markers defined. The texture analysis was performed using fractal approaches avoiding the problems of the variations in the acquisition among different clinical centers and comparing different computing methods. Trabecular bone texture was analyzed at different ranges of scale in order to characterize the underlying mechanisms of the microarchitecture modification induced by the knee osteoarthritis. Thus, we highligthed the predictive interest of this cheap and largely available analysis for both the initiation and the progression of the knee osteoarthritis
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Butler, Anthony Philip Howard. "Eigenimage Processing of Frontal Chest Radiographs." Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/2780.
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The goal of this research was to improve the speed and accuracy of reporting by clinical radiologists. By applying a technique known as eigenimage processing to chest radiographs, abnormal findings were enhanced and a classification scheme developed. Results confirm that the method is feasible for clinical use. Eigenimage processing is a popular face recognition routine that has only recently been applied to medical images, but it has not previously been applied to full size radiographs. Chest radiographs were chosen for this research because they are clinically important and are challenging to process due to their large data content. It is hoped that the success with these images will enable future work on other medical images such as those from CT and MRI. Eigenimage processing is based on a multivariate statistical method which identifies patterns of variance within a training set of images. Specifically it involves the application of a statistical technique called principal components analysis to a training set. For this research, the training set was a collection of 77 normal radiographs. This processing produced a set of basis images, known as eigenimages, that best describe the variance within the training set of normal images. For chest radiographs the basis images may also be referred to as 'eigenchests'. Images to be tested were described in terms of eigenimages. This identified patterns of variance likely to be normal. A new image, referred to as the remainder image, was derived by removing patterns of normal variance, thus making abnormal patterns of variance more conspicuous. The remainder image could either be presented to clinicians or used as part of a computer aided diagnosis system. For the image sets used, the discriminatory power of a classification scheme approached 90%. While the processing of the training set required significant computation time, each test image to be classified or enhanced required only a few seconds to process. Thus the system could be integrated into a clinical radiology department.
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Brooks, Kenneth W. "Automated analysis of mammography phantom images." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/17900.
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Sousa, Cláudia Maria Romano de. "\"Estudo comparativo da cefalometria do perfil tegumentar com base na análise facial de Arnett relacionada à horizontal verdadeira com a realizada a partir do plano de Frankfurt horizontal\"." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/23/23139/tde-15052007-144613/.
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Nesta pesquisa foi comparada a diferença das medidas obtidas utilizando-se a análise cefalométrica do perfil tegumentar tendo como base a análise facial de Arnett relacionada à Horizontal Verdadeira com a análise cefalométrica do perfil tegumentar feita a partir do Plano de Frankfurt. Utilizamos 140 radiografias cefalométricas requisitadas como parte de documentação ortodôntica, obtidas de pacientes com idade variando de 06 a 49 anos, sendo 64 do sexo masculino e 76 do sexo feminino, pertencentes ao arquivo do IOM - (Instituto de Odontologia Multidisciplinar) ? RJ. As radiografias cefalométricas em norma lateral foram obtidas pelo mesmo operador, obedecendo ao protocolo adotado pelo IOM. Todos os pacientes foram orientados a assumir a Posição Natural da Cabeça, tendo como referência um espelho posicionado a frente e a Linha Vertical Verdadeira foi obtida por meio da utilização de um fio metálico unido à um prumo de chumbo, posicionado próximo à margem anterior do chassi porta-filme, de forma que apareça à frente do perfil tegumentar do paciente. A partir das medidas lineares obtidas nas Análises Cefalométricas dos Tecidos Moles, foram realizadas análises estatísticas visando dois objetivos: comparar as medidas de A à I obtidas nos traçados (um utilizando como referência uma perpendicular ao Plano Horizontal de Frankfurt e o outro à Linha Vertical Verdadeira) e analisar os resultados comparativamente. Após a análise estatística (Kolmogorov-Smirnov, para distribuição normal de dados; t-Student para amostras emparelhadas e teste não paramétrico de Wilcoxon) e a interpretação dos resultados obtidos, concluímos que houve diferenças significantes entre as formas de medidas das variáveis A, B, C, D, F, G e I, pois o valor do nível descritivo (p-valor) se apresentou abaixo de 0,05. Entretanto para as medidas E e H o valor do nível descritivo (p-valor) se apresentou maior que 0,05, demonstrando não haver diferenças significantes entre as formas dessas medidas. As correlações entre as medidas apresentadas estabelecidas pela análise facial de Arnett, de acordo com este estudo, não deverão ser utilizadas em pacientes que se submeteram à radiografias cefalométricas realizadas a partir do Plano Horizontal de Frankfurt, salvo no caso da distância interlabial, representada pela medida H, que além de não apresentar diferenças significantes neste estudo, não tem, segundo a análise de Arnett, correlação com nenhuma outra medida.<br>In this research a comparison was made between the differences in measurements obtained using the soft tissue profile?s cephalometric analysis based on Arnett?s facial analysis related to the true vertical with the cephalometric analysis of soft tissue profile based on the Frankfurt Plan. A total of 140 lateral cephalometric radiographs were used as part of the orthodontic documentation, taken from patients whose ages ranged from 06 to 49 years of age, of these 64 males and 76 females, being part of the files of the IOM (Instituto de Odontologia Multidisciplinar do Rio de Janeiro). The lateral cephalometric radiographs were obtained from the same operator obeying the protocols adapted by the IOM. All patients were oriented to place themselves in the Natural Head Posture using, as a reference, a mirror in front of then and the true vertical line was obtained using a metal wire and a plumb-line, placed close to the frontal chassis of the film chamber, in such a way that it appears in front of the soft tissue profile of the patient. Parting from the lineal measurements obtained from the Cephalometric Analyses of the Soft Tissues statistical analyses were made relating to two objectives: to compare the measurements from A to I obtained from the drafts/ sketches (one using as it reference a perpendicular to the Frankfurt Horizontal Plane and the other the True Vertical Line), comparatively analyse these results. After the statistical analysis (Kolgomorov Smirnov) for a normal data distribution: t-student for matched pairs and the no-parametric Wilcanox test) and the analysis of the results obtained, it was concluded that there were significant differences between the forms of the measurements of the variables A, B, C, D, F, G and I since the descriptive value (p-value) was below 0,05. The measurements for E and H, however, being over 0,05, showing than there were no significant differences between these forms of measurement. The correlation between the demonstrated measurements established by Arnett?s facial analysis, in accordance with this study, should not be used in patients who have undergone lateral cephalometric radiograph initiated on the basis of the Frankfurt Horizontal Plane except in the case of interlabial distance represented by the measurement H, which even differences in this study, does not have, according to Arnett?s studies, correlations with any other measurements.
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Jennane, Rachid. "Modélisation fractale de textures : application à l'analyse de l'architecture osseuse." Orléans, 1995. http://www.theses.fr/1995ORLE2050.
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Cette these est composee de deux parties. La premiere a pour but de valider une analyse fractale orientee (afo) de la texture d'une image ; la deuxieme est une application de cette analyse a des images radiographiques d'os. L'afo d'une image consiste a estimer le parametre h du mouvement brownien fractionnaire (fbm) le long de lignes de niveaux de gris paralleles dans des directions differentes. Le but est double: chiffrer la rugosite de la texture et rendre compte de son anisotropie. Pour valider cette methode sur des images synthetiques, nous proposons tout d'abord une methode pour evaluer la qualite des techniques de synthese 1d du fbm. Puis, sur des signaux de reference, nous comparons differents estimateurs de h pour ne retenir que les meilleurs en termes de biais et de variance. Les methodes de synthese selectionnees dans le cas 1d sont ensuite etendues pour obtenir des textures isotropes et anisotropes. Ces images sont ensuite analysees par afo et les resultats sont reportes sur un diagramme polaire dont l'analyse harmonique permet de valider la methode et d'extraire des parametres caracteristiques de la texture. L'afo est ensuite utilisee pour caracteriser la texture des images osseuses et quantifier le processus de decalcification de l'os. En premier lieu, les images d'os de deux populations (temoins, osteoporotiques) sont analysees. Ensuite, des resultats issus de l'afo sont interpretes en liaison avec ceux d'une analyse histomorphometrique et ceux d'une evaluation de la resistance osseuse par des tests biomecaniques. Finalement, d'autres attributs de texture sont estimes sur nos images d'os par matrice de co-occurence et matrice de longueurs de plages. Quoique perfectible, l'outil que nous proposons semble prometteur en vue de quantifier les changements architecturaux de l'os trabeculaire lies a l'osteoporose
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Raheja, Aarti. "AUTOMATED ANALYSIS OF METACARPAL CORTICAL THICKNESS IN SERIAL HAND RADIOGRAPHS." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1229953773.
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Thomson, Jessie. "Algorithms for automatic analysis of radiographs of the knee with application in diagnosis and monitoring of osteoarthritis." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/algorithms-for-automatic-analysis-of-radiographs-of-the-knee-with-application-in-diagnosis-and-monitoring-of-osteoarthritis(22af4216-3ff4-41b5-ac44-1dd4d83a53bd).html.
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Osteoarthritis (OA) of the knee is a disease that deteriorates the bones and surrounding soft tissue of the affected joint. Categorisation of the disease into grades of severity is subject to errors of measurement and poor observer agreement. There is an urgent need for automated methods to measure radiographic features and remove, as far as possible, the element of subjectivity in assessment. This project creates a fully automated system to analyse all aspects of the knee in radiographs. The methods evaluate explicit and implicit features of: overall shape, trabecular structure, osteophytes, tibial spines and intercondylar notch, and joint space shape. The project develops the first fully automated osteophyte detection algorithms, improved trabeculae features using raw pixel intensities, and a better analysis of joint space using shape models. This project is the first to combine explicit and implicit features across the whole of the knee, and applies these features to classify radiographs using four main outcomes: current OA, current pain, later onset OA, and later onset pain. The results find a strong current OA classification rate, with an Area Under the ROC Curve (AUC) of 0.904 and weighted kappa of 0.49 (0.48-0.51). The remaining later onset and pain experiments report weaker results; these results suggest that radiographic features in Posterior-Anterior (PA) view radiographs have a weak association with clinical and later onset OA.
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Thiagarajah, Shankar. "The role of radiographic endophenotyping in signal detection in genome-wide association analyses of osteoarthritis." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/18391/.
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Introduction: Despite OA heritability estimated at 40-65%, fewer than 20 robustly-associated genetic loci explaining ~10% of heritability have been identified. Genome-wide association studies (GWAS) have been limited by modest sample sizes and the employment of simple dichotomous descriptions of joint involvement. Risk loci associated with hip shape variation, a heritable risk factor for the development of OA, is also largely unknown. Aims: We aimed to determine whether case stratification into precise phenotypic sub-categories is a critical parameter in signal detection in GWAS of hip and knee OA, and hip shape variation. This has not previously been tested systematically. Method: This thesis describes several nested studies from the arcOGEN resource. We initially describe several GWAS in 2,118 cases with radiographic hip OA, stratified by site of maximal joint space narrowing and bone remodelling response, versus 6,500 population-based controls (PBC). We also performed several GWAS’ of 2,010 cases with radiographic knee OA, stratified by dominant compartment involvement, versus 6,500 PBC. Finally, we describe several GWAS with radiographically-derived indices of acetabular and proximal femoral shape. Results: We identified suggestive evidence (p < 9.9 x 10-6) of associations at 6 and 10 variants with hip and knee OA endophenotypes respectively. All would have been missed by a broad phenotype definition approach. The signal yield was increased beyond that associated with chance. Compartmental stratification at the knee also increased the disease heritability estimate. We identified 4 loci (p < 9.9 x 10-6) associated with hip shape variation, including associations with genes regulating myogenesis and skeletal development. Conclusion: We show that increased phenotypic definition in nested case/control cohorts of OA leads to substantial increases in signal detection for susceptibility loci. We report novel associations that were entirely obscured by the heterogeneity of the disease, indicating that the use of narrower OA phenotype definitions can lead to a comprehensive account of variants affecting risk.
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Cerneaz, Nicholas J. "Model-based analysis of mammograms." Thesis, University of Oxford, 1994. http://ora.ox.ac.uk/objects/uuid:a8d91bb2-429c-4da3-9f1b-6209771c61b5.
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Metastasised breast cancer kills. There is no known cure, there are no known preventative measures, there are no drugs available with proven capacity to abate its effects. Early identification and excision of a malignancy prior to metastasis is the only method currently available for reducing the mortality due to breast disease. Automated analysis of mammograms has been proposed as a tool to aid radiologists detect breast disease earlier and with greater efficiency and success. This thesis addresses some of the major difficulties associated with the automated analysis of mammograms, in particular the difficulties caused by the high-frequency, relatively insignificant curvi-linear structures (CLS) comprising the blood vessels, milk-ducts and fibrous tissues. Previous attempts at automation have been overlooked these structures and the resultant complexity of that oversight has been handled inappropriately. We develop a model-based analysis of the CLS features, from the very anatomy of the breast, through mammography and digitisation to the image intensities. The model immediately dictates an algorithm for extracting a high-level feature description of the CLS features. This high-level feature description allows a systematic treatment of these image features prior to searching for instances of breast disease. We demonstrate a procedure for implementing such prior treatment by 'removing' the CLS features from the images. Furthermore, we develop a model of the expected appearance of mammographic densities in the CLS-removed image, which leads directly to an algorithm for their identification. Unfortunately the model also extracts many regions of the image that are not significant mammographic densities, and this therefore requires a subsequent segmentation stage. Unlike previous attempts which apply neural networks to this task, and therefore incorporate inherent insignificance as a consequence of insufficient data availability describing the significant mammographic densities, we illustrate the application of a new statistical method (novelty analysis) for achieving a statistically significant segmentation of the mammographic densities from the plethora of candidates identified at the previous stage. We demonstrate the ability of the CLS feature description to identify instances of radial-scar in mammograms, and note the suitability of the CLS and density descriptions for assessment of bilateral and temporal asymmetry. Some additional potential applications of these feature descriptions in arenas other than mammogram analysis are also noted.
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Chehade, Mellick Joseph. "Bone resonance analysis, histomorphometry and the mechanics of fracture healing." Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phc515.pdf.
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Lemineur, Gérald. "Contributions à l'analyse fractale de radiographies osseuses pour le diagnostic de l'ostéoporose." Orléans, 2003. http://www.theses.fr/2003ORLE2065.
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Le diagnostic précoce de l'ostéoporose nécessite, en plus de la mesure de la densité osseuse actuellement réalisée en routine clinique, un examen permettant de caractériser la microarchitecture 3D. Une technique basée sur l'analyse fractale orientée d'une radiographie 2D a été mise au point à Orléans. Le but de ce travail est d'apporter des améliorations, aussi bien fondamentales que technologiques, à la technique. Trois parties composent cette thèse. Dans la première partie, nous présentons une étude des relations entre les volumes osseux et leur projection 2D. Tout d'abord, les corrélations existant entre les propriétés microarchitecturales 3D de l'os et la dimension fractale de sa projection ont été analysées. On observe que le paramètre fractal reflète l'évolution de la plus part des paramètres microarchitecturaux 3D. L'étape suivante consiste à tester sur nos données un théorème qui relie l'autosimilarité 3D d'un volume avec l'autosimilarité 2D de sa projection. Il s'avère que la relation est vérifiée pour des volumes osseux. Le paramètre fractal ne permet pas de quantifier l'anisotropie qui joue un rôle important dans la résistance mécanique de l'os. Ainsi, dans une seconde partie, différentes techniques d'estimation de l'anisotropie ont été présentées puis testées sur des images radiographiques. Deux méthodes, l'une basée sur une analyse fractale et l'autre sur l'exploitation du spectre de Fourier, ont permis d'obtenir de bons résultats. Dans la dernière partie, nous présentons le prototype d'un appareil de radiographie numérique haute résolution. Nous montrons l'apport du numérique en terme de résolution par rapport aux clichés. Enfin, nous présentons les premiers résultats de reproductibilité obtenus avec ce prototype numérique.
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Elouafkaoui, Paula. "Variation in treatment : an analysis of dental radiographs using matched patient provider data." Thesis, University of Dundee, 2011. https://discovery.dundee.ac.uk/en/studentTheses/4349965c-22fe-46d1-ac9e-e6345a535781.
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Variation in health care, whether it be in terms of the utilisation of resources, observed health outcomes, costs, quality or access to health care is a well recognised and ever present feature of the modern day health care system. Health care variations challenge basic assumptions about the nature of the health care economy and raise questions about efficiency, equity and where best to direct policy instruments in health care markets. Despite the vast literature documenting variation, and the many discussions around ways to reduce variations in health care markets, the field of dental care has received little interest, in comparison to that of general medical care. This thesis will address this gap and will analyse the variation observed in a specific dental care treatment (dental radiographs) within NHS Scotland, with particular emphasis on the contribution of both dentist and patient unobserved heterogeneity. The thesis takes its focus from two strands of the literature; the underlying theoretical aspect draws on the literature concerning the theory of incentives and physician agency, whilst the empirical component makes use of recent advances in micro-econometric methods, documented in the labour economics literature. Although the thesis is predominantly an empirical analysis, the estimation strategy combines ideas from both the theoretical and empirical literature. A matched patient provider dataset from NHS Scotland is used to conduct an analysis of the variation in dental radiographs, in the presence of, and controlling for unobserved dentist and patient heterogeneity. The results indicate that the remuneration structure alone has little or no impact on the treatment decision to provide a radiograph. When a dentist changes from being on a fixed salary contract to being paid on a fee-for-service basis, they are in fact less likely to provide a radiograph. This result changes in the presence of insurance (identified as being when patients are exempt from the patient charge) and indicates that when the self employed dentist can identify the patient as being exempt, they are more likely to provide a radiograph. This result provides some support for the theory that in the presence of insurance, financial incentives do influence the treatment decision. A final result of the study highlights the importance of accounting for unobserved patient and provider heterogeneity, a factor that has had little attention in the healthcare literature. The results suggest that patient variation, as opposed to the variation across dentists, is much more important in explaining total variation. This is a similar result to that found in both the labour and education literatures.
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Kwok, Sze Man Simon. "Attribute-driven segmentation and analysis of mammograms." University of Western Australia. Centre for Intelligent Information Processing Systems, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0010.
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[Truncated abstract] In this thesis, we introduce a mammogram analysis system developed for the automatic segmentation and analysis of mammograms. This original system has been designed to aid radiologists to detect breast cancer on mammograms. The system embodies attribute-driven segmentation in which the attributes of an image are extracted progressively in a step-by-step, hierarchical fashion. Global, low-level attributes obtained in the early stages are used to derive local, high-level attributes in later stages, leading to increasing refinement and accuracy in image segmentation and analysis. The proposed system can be characterized as: • a bootstrap engine driven by the attributes of the images; • a solid framework supporting the process of hierarchical segmentation; • a universal platform for the development and integration of segmentation and analysis techniques; and • an extensible database in which knowledge about the image is accumulated. Central to this system are three major components: 1. a series of applications for attribute acquisition; 2. a standard format for attribute normalization; and 3. a database for attribute storage and data exchange between applications. The first step of the automatic process is to segment the mammogram hierarchically into several distinctive regions that represent the anatomy of the breast. The adequacy and quality of the mammogram are then assessed using the anatomical features obtained from segmentation. Further image analysis, such as breast density classification and lesion detection, may then be carried out inside the breast region. Several domain-specific algorithms have therefore been developed for the attribute acquisition component in the system. These include: 1. automatic pectoral muscle segmentation; 2. adequacy assessment of positioning and exposure; and 3. contrast enhancement of mass lesions. An adaptive algorithm is described for automatic segmentation of the pectoral muscle on mammograms of mediolateral oblique (MLO) views
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Bacchuwar, Ketan. "Image processing for semantic analysis of the coronary interventions in cardiology." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1074/document.
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L'intervention coronarienne percutanée (ICP) est réalisée en utilisant l'imagerie radiographique en temps réel dans une suite interventionnelle. La modélisation de ces procédures ICP pour aider le praticien implique la compréhension des différentes phases de la procédure ICP, par la machine d’intervention, qui peut être utilisées pour optimiser la dose de rayons X et l'agent de contraste. Pour atteindre cet objectif, l’une des tâches importantes consiste à segmenter différents outils d’intervention dans les flux d’images fluoroscopiques et à en déduire des informations sémantiques. L’arbre des composants, un puissant outil morphologique mathématique, constitue la base des méthodes de segmentation proposées. Nous présentons ce travail en deux parties: 1) la segmentation du cathéter vide à faible contraste, et 2) la segmentation de la pointe du guide et le suivi de la détection du vaisseau d’intervention. Nous présentons une nouvelle méthode de segmentation basée sur l’espace à plusieurs échelles pour détecter des objets faiblement contrastés comme un cathéter vide. Pour la dernière partie, nous présentons la segmentation de la pointe du guide avec le filtrage basé sur l’arbre de composants et proposons un algorithme pour suivre sémantiquement la pointe segmentée pour déterminer le vaisseau d’intervention<br>Percutaneous coronary intervention (PCI) is performed using real-time radiographic imaging in an interventional suite. Modeling these ICP procedures to help the practitioner involves understanding the different phases of the ICP procedure, by the interventional machine, which can be used to optimize the X-ray dose and the contrast agent. One of the important tasks in achieving this goal is to segment different interventional tools into the flow of fluoroscopic images and to derive semantic information from them. The component tree, a powerful mathematical morphological tool, forms the basis of the proposed segmentation methods. We present this work in two parts: 1) the segmentation of the low-contrast empty catheter, and 2) the segmentation of the tip of the guide and the monitoring of the detection of the intervention vessel. We present a new multi-scale space-based segmentation method for detecting low-contrast objects such as an empty catheter. For the last part, we present the segmentation of the tip of the guide with filtering based on the component tree and propose an algorithm to semantically follow the segmented tip to determine the intervention vessel
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Girard, Stéphane. "Construction et apprentissage statistique de modèles auto-associatifs non-linéaires : application à l'identification d'objets déformables en radiographie." Paris, CNAM, 1996. http://biblioweb.u-cergy.fr/theses/96CERG0015.pdf.
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En radiographie numérique la comparaison de l'image d'une pièce à un ensemble d'images de références est une technique permettant de pallier le problème de superposition ou de détecter des défauts de fabrication. Lorsque l'objet observé n'est pas de géométrie fixe, la comparaison demande de construire un modèle capable de représenter l'objet et ses éventuelles déformations. Nous présentons dans cette thèse une méthode originale pour construire un modèle à partir d'un jeu d'exemples. Le problème est considéré du point de vue de l'analyse des données multidimensionnelles, ce qui assure un apprentissage des déformations applicable à une grande classe de problèmes. Dans une première partie, nous traitons un exemple de contrôle par radiographie de soudures de circuits imprimés. Nous montrons comment un modèle linéaire des déformations d'une patte de circuit imprimé permet de construire une image caractéristique des soudures. Dans une seconde partie, nous montrons les limites du modèle linéaire sur des simulations de déformation de courbes, et nous proposons une méthode innovante de construction de modèles non-linéaires. Ces modèles, que nous appelons modèles composés, se placent dans le cadre des méthodes Auto-Associatives et s'appuient sur les techniques de Poursuite de Projection en Régression. En effet, nous prouvons d'une part que les modèles composés étendent les propriétés d'approximation des méthodes Auto-Associatives classiques et, d'autre part, nous adoptons une mise en œuvre par un algorithme itératif inspiré de la Poursuite de Projection. La convergence de cet algorithme vers la solution exacte en un temps fini est démontrée
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Batuka, Nabawesi Jennifer. "Pre and post computerized radiography film reject analysis in a private hospital in Kenya." Thesis, Nelson Mandela Metropolitan University, 2011. http://hdl.handle.net/10948/1574.
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The production of good quality radiographs is a complex process, given the high level of image quality required (Sniureviciute & Adliene, 2005: 260). Exposure of patients to x-rays, a factor in the production of quality radiographs also entails a risk of radiation injury. In 2006, computerized radiography (CR) was introduced at The Nairobi Hospital to try and reduce the film reject rate, decrease repeats, reduce financial costs of consumables like x-ray films and processing chemicals. However, to date, no formal film reject analysis has been conducted at The Nairobi Hospital. Four years after the incorporation of CR, there is apparently, still a significant number of film rejects, implying operational costs may still be high. The cause of film rejects and overall reject cost is not known. This has led to the research question: “Has the film reject rate in the A & E x-ray unit at The Nairobi Hospital reduced following incorporation of CR?” A quantitative, retrospective, descriptive study involving a reject film analysis of rejected radiographs in the Accident and Emergency (A&E) x-ray unit in the Nairobi Hospital, Kenya was conducted. The researcher collected data for a period of 6 months between 2/12/07 and 28/05/08 using a purpose-designed data collection form. All rejected x-ray films during the study period were included. Capture and analysis of the collected data was completed by the researcher using SPSS 10 and EPINFO computer packages. Permission to conduct the study was obtained from The Nairobi Hospital Education Committee and due consideration to patient and radiographer confidentiality was maintained throughout the study. A total of 851(2.5 percent) x-ray films were collected during the study period. Four hundred and fourteen (2.6 percent) radiographs and 437 (2.5 percent) radiographs were rejected prior to and after the incorporation of CR respectively. Chest radiographs were the most frequently rejected accounting for 277(66.9 percent) and 123 (28.1 percent) prior to and after the incorporation of CR respectively. The most frequently rejected film size was 35x35cm prior to the incorporation of CR (61.6 percent) and 26x35cm film size after the incorporation of CR (91.3 percent). The most frequent cause of film rejects was radiographer causes both prior to and after the incorporation of CR accounting for 496 (58.3 percent). The film reject rate did not significantly reduce after the incorporation of CR, suggesting that there are other factors which contribute to reject rate, other than CR. The study also shows that higher film consumption does not necessarily lead to high reject rates. The percentage value on annual rejects did not change after the incorporation of CR and a demonstrated increase in the annual cost of purchasing x-ray films was attributed to an increase in annual consumption after the incorporation of CR, and also to the higher cost of digital x-ray films. Despite some identified limitations to this study, some recommendations, which included conduction of regular reject analyses and regular continuing professional development with respect to radiographic technique amongst others, were suggested.
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Watts, Michael Robert. "The analysis of diffraction measurements of internal strains in metal matrix composites." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313918.
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Razafindralambo, Nathalie. "Limite de détection de la spectrométrie X pour l'anthroporadiamétrie pulmonaire du plutonium : analyse et perspectives de développement." Toulouse 3, 1995. http://www.theses.fr/1995TOU30186.
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Masek, Martin. "Hierarchical segmentation of mammograms based on pixel intensity." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2004. http://theses.library.uwa.edu.au/adt-WU2003.0033.
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Mammography is currently used to screen women in targeted risk classes for breast cancer. Computer assisted diagnosis of mammograms attempts to lower the workload on radiologists by either automating some of their tasks or acting as a second reader. The task of mammogram segmentation based on pixel intensity is addressed in this thesis. The mammographic process leads to images where intensity in the image is related to the composition of tissue in the breast; it is therefore possible to segment a mammogram into several regions using a combination of global thresholds, local thresholds and higher-level information based on the intensity histogram. A hierarchical view is taken of the segmentation process, with a series of steps that feed into each other. Methods are presented for segmentation of: 1. image background regions; 2. skin-air interface; 3. pectoral muscle; and 4. segmentation of the database by classification of mammograms into tissue types and determining a similarity measure between mammograms. All methods are automatic. After a detailed analysis of minimum cross-entropy thresholding, multi-level thresholding is used to segment the main breast tissue from the background. Scanning artefacts and high intensity noise are separated from the breast tissue using binary image operations, rectangular labels are identified from the binary image by their shape, the Radon transform is used to locate the edges of tape artefacts, and a filter is used to locate vertical running roller scratching. Orientation of the image is determined using the shape of the breast and properties of the breast tissue near the breast edge. Unlike most existing orientation algorithms, which only distinguish between left facing or right facing breasts, the algorithm developed determines orientation for images flipped upside down or rotated onto their side and works successfully on all images of the testing database. Orientation is an integral part of the segmentation process, as skin-air interface and pectoral muscle extraction rely on it. A novel way to view the skin-line on the mammogram is as two sets of functions, one set with the x-axis along the rows, and the other with the x-axis along the columns. Using this view, a local thresholding algorithm, and a more sophisticated optimisation based algorithm are presented. Using fitted polynomials along the skin-air interface, the error between polynomial and breast boundary extracted by a threshold is minimised by optimising the threshold and the degree of the polynomial. The final fitted line exhibits the inherent smoothness of the polynomial and provides a more accurate estimate of the skin-line when compared to another established technique. The edge of the pectoral muscle is a boundary between two relatively homogenous regions. A new algorithm is developed to obtain a threshold to separate adjacent regions distinguishable by intensity. Taking several local windows containing different proportions of the two regions, the threshold is found by examining the behaviour of either the median intensity or a modified cross-entropy intensity as the proportion changes. Image orientation is used to anchor the window corner in the pectoral muscle corner of the image and straight-line fitting is used to generate a more accurate result from the final threshold. An algorithm is also presented to evaluate the accuracy of different pectoral edge estimates. Identification of the image background and the pectoral muscle allows the breast tissue to be isolated in the mammogram. The density and pattern of the breast tissue is correlated with 1. Breast cancer risk, and 2. Difficulty of reading for the radiologist. Computerised density assessment methods have in the past been feature-based, a number of features extracted from the tissue or its histogram and used as input into a classifier. Here, histogram distance measures have been used to classify mammograms into density types, and ii also to order the image database according to image similarity. The advantage of histogram distance measures is that they are less reliant on the accuracy of segmentation and the quality of extracted features, as the whole histogram is used to determine distance, rather than quantifying it into a set of features. Existing histogram distance measures have been applied, and a new histogram distance presented, showing higher accuracy than other such measures, and also better performance than an established feature-based technique.
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Dubory, Arnaud. "Interface os-implant titane et ingénierie tissulaire A cadaveric validation of a method based on impact analysis to monitor the femoral stem insertion Bone marrow mesenchymal stem cells predict radiographic osseointegration of cementeless titanium hip cups Survival, adhesion, and expression of osteoblastic genes of human derived-bone marrow mesenchymal stromal cells on PEEK and titanium-coated PEEK lumbar interbody cages." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC0067.
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Introduction : Le titane, à la fois utilisé comme moyen de fixation d’un implant devant ses propriétés biomécaniques proches de l’os et comme moyen d’ostéointégration a pris une place prépondérante en orthopédie. L’ostéointégration d’un implant titane (IT) essentielle pour la pérennité de ce dernier, dépend de 2 phases : une phase primaire MECANIQUE correspondant à l’impaction ou tenue primaire de l’IT et une phase secondaire BIOLOGIQUE correspondant à la colonisation de l’IT par le tissu osseux.L’objectif de ce travail fut d’évaluer et d’améliorer lors de ces deux phases la stabilité et l’ostéointégration de l’implant titane :(1) Évaluer la tenue primaire des tiges fémorales en titane non cimentées par l’analyse de l’impact correspondant à la mesure de l’impact au cours du temps.(2) Évaluer si la quantité de CSM contenues dans l’aile iliaque est corrélée à la survie sans reprise de des implants acétabulaires impactés dans le cadre de l’ostéonécrose aseptique de la tête fémorale.(3) Améliorer l’ostéointégration des IT par les méthodes de thérapie cellulaire en étudiant in vitro la survie et la division des cellules stromales mésenchymateuses humaines (CSM) osseuses au contact de cages lombaires inter-somatiques recouvertes d’alliage titane rugueux.Matériels et Méthodes: L’évaluation de la tenue primaire des tiges fémorales en titane sans ciment selon l’analyse de l’impact a été réalisée à l’aide d’un marteau muni d’un capteur de force piézo-électrique sur 20 sujets anatomiques soit 40 hanches. On a comparé le nombre de coups de marteau pour obtenir l’impaction idéale de la prothèse selon 3 méthodes d’évaluation différentes : le nombre de coups nécessaires pour le chirurgien (Nchir), le nombre de coups nécessaires par l’analyse vidéo de l’enfoncement de la tige dans le fémur (Nvid) et le nombre de coups nécessaires par l’analyse de l’impact (NI).Pour savoir si la quantité de CSMs dans la crête iliaque pouvait refléter l’ostéointégration des implants acétabulaires impactées et le risque de reprise chirurgicale, on a comparé le taux de CSMs mesuré lors de la réalisation d’une ponction concentration et réinjection dans la zone d’ostéonécrose et l’évolution clinico-radiographique des implants acétabulaires mis en place par la suite pour ces même patients (n=90) qui ont eu une arthroplastie totale de hanche in fine. Le recul moyen était de 15 ans.La survie cellulaire des CSM osseuses humaines a été évaluée sur des cages intersomatiques lombaires recouvertes de titane. Trois groupes (n=5) furent constitués : un groupe contrôle, un groupe cages avec surface titane, un groupe cage sans titane. Sur chaque implant, 1 microlitre contenant 106 CSM osseuses humaines a été mis en culture. L’analyse de la survie cellulaire, de la prolifération cellulaire et de l’expression de gènes de différenciation ostéoblastique ont été réalisés et comparés.Résultats : Concernant la première étude sur l’intérêt de l’analyse de l’impact pour la tenue de la tige fémorale, la différence entre NI, Nchir et Nvid était inférieure ou égale à 3 pour plus de 85% des configurations réalisées. Concernant la deuxième étude, il a été mis en évidence qu’un faible nombre de CSM dans la crête iliaque était un facteur de risque de révision chirurgicale chez les patients traités par un implant acétabulaire sans ciment. La troisième étude a montré que les CSMs pouvaient survivre, se développer pendant 96 heures et exprimer des gènes de différenciation ostéoblastique de manière identique sur les cages avec ou sans titane.Conclusion : L’analyse de l’impact permet de donner une information objective sur la tenue primaire de la tige fémorale en titane et impactée. Le titane est aussi un milieu favorisé de survie et de prolifération des CSM osseuses prédestinées à devenir des cellules ostéoformatrices surtout qu’un faible nombre de CSM semble être un risque d’échec d’ostéointégration des implants acétabulaires sans ciment<br>Introduction: Titanium, both used as a mean of fixing an implant to its biomechanical properties close to the bone and as a mean of osseointegration has taken a prominent place. The implant stability is essential for the durability of a titanium implant (TI); it depends on 2 phases: a primary phase, MECHANICAL, corresponding to the impaction or primary holding of the TI and a secondary phase, BIOLOGICAL, corresponding to the colonization of TI by bone tissue.The objective of this work was to evaluate and improve during these two phases the osseointegration of the titanium implant:(1) To evaluate the primary stability of uncemented titanium femoral stems by impact analysis corresponding to the measurement of impact over time.(2) To evaluate whether the amount of mesenchymal stromal cells (MSCs) contained in the iliac crest is correlated with the non-recovery survival of acetabular implants impacted in a context of aseptic osteonecrosis of the femoral head.(3) To improve the osseointegration of TI by cell therapy methods in vitro by studying the survival and division of human MSCs in contact with interbody lumbar cages coated with rough titanium alloy.Methods: The evaluation of the primary stability of cementless titanium femoral stems according to the impact analysis was carried out using a hammer equipped with a piezoelectric force sensor on 20 anatomical subjects, i.e. 40 hips. The number of hammer strokes was compared to obtain the ideal impaction of the prosthesis according to 3 different evaluation methods: number of impacts required by the surgeon (Nsurg), number of impacts required by the video analysis of the depression of the stem in the femur (Nvid), numbers of impacts needed by the impact analysis (Ni).To determine whether the amount of MSCs in the iliac crest could reflect the osseointegration of impacted acetabular implants and the risk of surgical revision. The rate of MSCs measured when performing a surgical cell therapy for aseptic osteonecrosis of the femoral head and the clinical and radiographic outcome of acetabular implants subsequently established for these same patients (n = 90), who had total hip arthroplasty in fine were compared. The mean follow-up was 15 years.The cell survival of bone marrow-derived MSCs was evaluated on lumbar interbody cages coated with titanium. Three groups (n = 5) were formed: a control group, a cage group with titanium surface, a cage group without titanium. On each implant, 1 microliter containing 106 human bone MSCs was cultured. The analysis of cell survival, cell proliferation and expression of osteoblastic genes were performed and compared.Results: Regarding the impact analysis of the cementless femoral stem impaction, the difference between NI, Nchir and Nvid was lower than 3 for more than 85% of the configurations performed.For the second study, a small number of MSCs in the iliac crest was a risk factor for surgical revision in patients treated with a cementless acetabular implant.The third study showed that MSCs could grow until 96 hours and could express osteoblastics genes 21 days after cell seed. No difference between PEEK cage and Titanium-coated PEEK has been found.Conclusion: The impact analysis provides objective data on the primary holding of the titanium impacted femoral stem. Titanium is also a favored biomaterial for the survival and proliferation of bone marrow-derived MSC predestined to become osteforming cells, especially since a small number of MSCs seems to be a risk of failure of osseointegration of cementless acetabular implants
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Butt, Ali. "Dynamic calibration and analysis of crack tip propagation in energetic materials using real-time radiography." Thesis, The University of Alabama in Huntsville, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1603134.
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<p> Crack propagation in a solid rocket motor environment is difficult to measure directly. This experimental and analytical study evaluated the viability of real-time radiography for detecting bore regression and propellant crack propagation speed. The scope included the quantitative interpretation of crack tip velocity from simulated radiographic images of a burning, center-perforated grain and actual real-time radiographs taken on a rapid-prototyped model that dynamically produced the surface movements modeled in the simulation. The simplified motor simulation portrayed a bore crack that propagated radially at a speed that was 10 times the burning rate of the bore. Comparing the experimental image interpretation with the calibrated surface inputs, measurement accuracies were quantified. The average measurements of the bore radius were within 3% of the calibrated values with a maximum error of 7%. The crack tip speed could be characterized with image processing algorithms, but not with the dynamic calibration data. The laboratory data revealed that noise in the transmitted X-Ray intensity makes sensing the crack tip propagation using changes in the centerline transmitted intensity level impractical using the algorithms employed.</p>
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Becconsall, Karyn, and n/a. "Analysis of radiolucent jaw lesions in a New Zealand population over a twenty-year period." University of Otago. School of Dentistry, 2008. http://adt.otago.ac.nz./public/adt-NZDU20081202.144835.
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The maxilla and mandible may be affected by a wide variety of lesions of developmental, neoplastic or inflammatory origin. These lesions have a vast array of clinical and radiographic presentations from which a dentist forms a clinical provisional diagnosis and treats the lesions accordingly. The aim of this study was to determine the range, demographic and clinical features of all histologically diagnosed radiolucent jaw lesions in a New Zealand population over a twenty-year period. Additionally, the provisional diagnosis was compared to the histopathological diagnosis in an effort to gain an insight into the difficulties practitioners face in clinically diagnosing radiolucent jaw lesions.
Material and Methods: From the histopathology diagnostic service at the University of Otago School of Dentistry all specimens with a diagnosis of a radiolucent jaw lesion between 1986 and 2006 were retrieved and classified into six diagnostic categories. For each lesion the age, gender, site, clinical presentation, clinicians provisional diagnosis and the final histological diagnosis was gathered and analysed.
Results: During the study period 4983 specimens were identified as radiolucent jaw lesions. The diagnostic category with the largest number of specimens was inflammatory lesions (72.8%), followed by developmental odontogenic cysts (21.8%). Malignant tumours accounted for less than 1% of all specimens. Concordance of provisional and histopathological diagnoses ranged from 81.0% for nasopalatine duct cyst to 0% for the majority of intra-osseous malignant tumours.
Conclusions: The range and demographic features of radiolucent jaw lesions in this study are comparable to that of other populations with a European majority. No radiolucent jaw lesion can be reliably accurately diagnosed from clinical presentation and radiographic appearance alone.
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Cantlay, Nicholas. "Sonographers' experiences of breaking bad news in prenatal ultrasound : a phenomenological analysis." Thesis, Lancaster University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.654968.
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Brummer, Marijn E. "Volumetric analysis of three-dimensional tomographic magnetic resonance brain images." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/14883.
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Berthonnaud, Éric. "Les mesures sur radiographies planes et tridimensionnelles en orthopédie : applications cliniques." Lyon 1, 2000. http://www.theses.fr/2000LYO1T005.
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ISHIGAKI, TAKEO, SADAYUKI SAKUMA, and MICHIKO SAKAI. "Osseous Lesions of the Hand and Foot in Diabetes Mellitus: Correlation between Magnification Roentgenographic Findings and Clinical Findings." Nagoya University School of Medicine, 1986. http://hdl.handle.net/2237/17492.
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Syrowatka, Ania. "Understanding the Role of the Ottawa Ankle Rules in Physicians' Radiography Decisions: A Social Judgment Analysis Approach." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/22854.
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Clinical decision rules improve health care fidelity, benefit patients, physicians and healthcare systems, without reducing patient safety or satisfaction, while promoting cost-effective practice standards. It is critical to appropriately and consistently apply clinical decision rules to realize these benefits. The objective of this thesis was to understand how physicians use the Ottawa Ankle Rules to guide radiography decision-making. The study employed a clinical judgment survey targeting members of the Canadian Association of Emergency Physicians. Statistical analyses were informed by the Brunswik Lens Model and Social Judgment Analysis. Physicians’ overall agreement with the ankle rule was high, but can be improved. Physicians placed greatest value on rule-based cues, while considering non-rule-based cues as moderately important. There is room to improve physician agreement with the ankle rule and use of rule-based cues through knowledge translation interventions. Further development of this Lens Modeling technique could lend itself to a valuable cognitive behavioral intervention.
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Erskine, Richard B. "A method of three-dimensional analysis of skull radiographs using paired views with selected rotation between exposure." Thesis, University of Dundee, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261784.
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