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Bestimmung der radio-ulnaren Inkongruenz bei Hunden mit Ellbogengelenksdysplasie anhand von 3D-RekonstruktionenEljack, Hamdi 11 March 2015 (has links)
Einleitung
Die klinische Bedeutung einer radio-ulnaren Inkongrunz (RUI) bei Hunden mit Ellbogengelenksdysplasie, sowie die präzise Bestimmung einer geringgradigen RUI sind umstrittene Fragestellungen in der Kleintierorthopädie.
Zielstellung
(1) die 3D-Technik zur Bestimmung einer RUI in ihrer Genauigkeit zu verbessern
(2) mit Hilfe dieser verbesserten Technik, die Beziehung zwischen Ausprägung und Grad einer vorliegenden RUI und dem Ausmaß an damit verbundenen Gelenkschäden im medialen Kompartiment des Ellbogengelenkes zu untersuchen.
Material und Methoden
In einer ersten Studie wurden 63 CT-basierte 3D-Modelle der radio-ulnaren Gelenkpfanne mit bekannter RUI (-2mm, -1 mm, 0 mm, +1 mm, +2 mm), unter Verwendung einer Kugel, welche genau der Incisura trochlearis jedes individuellen Modells angepasst war, bezüglich der vorhanden RUI untersucht. Diese Messungen erfolgten geblindet in zufälliger Reihenfolge der 63 Modelle und wurden hinsichtlich Spezifität und Sensitivität ausgewertet.
In der zweiten Studie wurden 86 Ellbogengelenke klinischer Patienten retrospektiv mit der neuen 3D-Kugel-Methode bezüglich ihrer RUI vermessen. Dieser Wert wurde in Beziehung mit dem in der Arthroskopie diagnostizierten Gelenkschaden im medialen Kompartiment gesetzt (Korrelation nach Pearson und logistische Regression), wobei die Gelenke in zwei Gruppen unterteilt wurden; die mit geringen Veränderungen (FPC-Gruppe) und solche mit fortgeschrittenen Schäden (MCD-Gruppe).
Ergebnisse
Unter Verwendung der Kugel-Methode betrug die mediane Sensitivität eine RUI auf einen Millimeter genau zu bestimmen 0,94 wobei die mediane Spezifität bei 0,89 lag. Der intra-Class-Korrelationskoeffizient für die interobserver Übereinstimmung betrug 0,99. 14 % der Gelenke wiesen eine negative RUI auf, 40 % zeigten keine messbare RUI und 46 % wiesen eine positive RUI auf. Das Quotenverhältnis (odds ratio) für das Vorliegen fortgeschrittener Gelenkschäden betrug für jeden Millimeter RUI 6,4.
Schlussfolgerungen
Die Anwendung der Kugel-Methode verbessert die Diagnose der RUI deutlich. Der vermutete Zusammenhang zwischen RUI und Gelenkschäden konnte mit der klinischen Studie bestätigt werden. Allerdings ist bemerkenswert, dass 40 % der Gelenke keine RUI aufwiesen. Somit ist davon auszugehen, dass andere Faktoren neben einer RUI an der Pathogenese klinisch beobachteter Gelenkschäden beteiligt sind. Ebenso ist festzustellen, dass ca. 15 % der Gelenke eine negative RUI aufweisen. Somit scheint es nicht gerechtfertigt alle Gelenke mit einer Form der Ellbogenosteotomie zu behandeln, da eine negative bzw. positive RUI und insbesondere keine RUI unterschiedliche geometrische Korrekturen benötigen.:1 EINLEITUNG 1
2 PUBLIKATIONEN 3
2.1 Sensitivity and specificity of 3D models of the radioulnar joint cup
in combination with a sphere fitted to the ulnar trochlear notch for
estimation of radioulnar incongruence in vitro 3
2.2 Relationship between axial radio-ulnar incongruence with cartilage
damage in dogs with medial coronoid disease 16
3 DISKUSSION 32
4 ZUSAMMENFASSUNG 36
5 SUMMARY 38
6 LITERATURVERZEICHNIS 40 / Introduction
The clinical significance of RUI in dogs with elbow dysplasia and precise estimation of small degree of RUI are controversial topics in small animal orthopedics.
Objectives
(1) improve the accuracy of the 3D technique for the estimation of RUI
(2) using the improved technique to examine the relationship between the shape and degree of present RUI and the amount of related joint damage in the medial compartment of the elbow joint.
Material and methods
In a first study, 63 CT-based 3D models of the radio-ulnar joint cup with known RUI (-2 mm, -1 mm, 0 mm, mm +1, +2 mm) were examined us-ing a sphere, which was exactly fitted to the trochlear ulnar notch of each individual model. The assessment of the radioulnar joint conformation was evaluated blindly in a random manner and analized in respect to sensitivity and specificity. In the second study, 86 elbow joints of clinical patients were retrospectively graded with the new 3D sphere technique with respect to their RUI. This value was correlated with the arthroscopically diagnosed joint damage in the medial compartment, where the joints were divided into two groups. Those with minor changes (g-FPC) and those with advanced damage (g-MCD).
Results
By using the sphere fitting technique, the median sensitivity of a RUI on a millimeter basis was 0.94 and the median specificity was 0.89. The intra-class correlation coefficient for interobserver agreement was 0.99. In the clinical joints 14 % had a negative RUI, 40 % showed no measurable RUI and 46% had a positive RUI. The odds ratio for the presence of advanced joint damage for every millimeter RUI was 6.4
Conclusions
The application of the sphere fitting technique significantly improves the diagnosis of the RUI. The assumed relationship between RUI and joint damage could be confirmed in the clinical study. However, it is noteworthy that 40 % of the joints showed no RUI. Thus, it can be assumed that other factors besides RUI are playing rule in the pathogenesis of clinically observed joint damages.
Also it should be noted that approximately 15 % of the joints have a negative RUI. Thus, it does not seem to be wise to treat all the joints with a type of elbow osteotomy, as a negative or positive RUI and in particular no RUI need different geometric corrections:1 EINLEITUNG 1
2 PUBLIKATIONEN 3
2.1 Sensitivity and specificity of 3D models of the radioulnar joint cup
in combination with a sphere fitted to the ulnar trochlear notch for
estimation of radioulnar incongruence in vitro 3
2.2 Relationship between axial radio-ulnar incongruence with cartilage
damage in dogs with medial coronoid disease 16
3 DISKUSSION 32
4 ZUSAMMENFASSUNG 36
5 SUMMARY 38
6 LITERATURVERZEICHNIS 40
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Comparação em meio digital entre os eixos transversais horizontais mandibulares definidos anatomicamente e por axiografia / Comparison in 3D environment between the mandibular horizontal transverse axis defined anatomically and through axiographyYanikian, Fabio 10 June 2016 (has links)
O objetivo deste estudo foi comparar o eixo de rotação verdadeiro com o anatômico em ambiente virtual 3D, e seus efeitos sobre dois pontos anatômicos mandibulares. O eixo verdadeiro foi determinado em 14 indivíduos por meio de axiografia, e transferido para o ambiente virtual por TCFC, e posteriormente determinado anatomicamente, onde foram medidas as distâncias entre ambos. Foram simuladas rotações de 2º, 5º e 8º da mandíbula nos dois eixos, tanto para abertura como fechamento, e quantificadas as diferenças nos pontos da linha média inferior (LMI) e pogônio (Pg). O teste t pareado foi utilizado para examinar as diferenças entre as médias nas posições desses pontos (p<0,05). Os eixos verdadeiros localizaram-se dentro de um raio de 5 mm do anatômico em 67,86% da amostra. A distância absoluta média entre os eixos foi de 4,79 mm, enquanto que a vetorial foi de 2,33 no plano horizontal e 3,03 mm no vertical, resultando na direção anteroinferior em 71,43% dos eixos verdadeiros. Houve diferença estatisticamente significante na posição dos pontos LMI e Pg para todas as magnitudes e direções, entre os eixos. O eixo verdadeiro está localizado na direção anteroinferior em relação ao anatômico. Os efeitos na mandíbula são significantes e diferentes em todas as amplitudes, tanto para abertura como fechamento, porém com possível pequena relevância clínica. / The aim of this study was to compare the true hinge axis to the anatomic one in a virtual 3D environment, and also their respective effects on two mandibular anatomic points. The true axis has been determined in 14 individuals by means of axiography, and later transferred to a virtual environment by CBTC, where the anatomical axis was determined, and measured the distances between them. Mandibular rotation of 2º, 5º and 8º in both axes were performed, both for opening and closing, as well as the quantification of the difference found in the points of the lower midline (LM) and pogonion (Pg). Paired t-test was used to examine differences between the average values in the position of those points (p<0,05). The true axis was located within a 5mm-radius of the anatomic axis throughout 67.86% of the sample. The average absolute distance between the axes was 4.79 mm, while the vector distance was 2.33 mm in the horizontal plane e 3.03mm in the vertical plane, amounting to an anteriorinferior direction of 71.43% of the true axis. There was significant difference in the position of points LM and Pg to all magnitudes and directions within the axes. The true hinge axis is located in the anterior-inferior direction in relation to the anatomic axis. The effects observed onto the mandible are significant and different in all amplitudes, both for opening and closing positions, however they present small clinical relevance.
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Comparação em meio digital entre os eixos transversais horizontais mandibulares definidos anatomicamente e por axiografia / Comparison in 3D environment between the mandibular horizontal transverse axis defined anatomically and through axiographyFabio Yanikian 10 June 2016 (has links)
O objetivo deste estudo foi comparar o eixo de rotação verdadeiro com o anatômico em ambiente virtual 3D, e seus efeitos sobre dois pontos anatômicos mandibulares. O eixo verdadeiro foi determinado em 14 indivíduos por meio de axiografia, e transferido para o ambiente virtual por TCFC, e posteriormente determinado anatomicamente, onde foram medidas as distâncias entre ambos. Foram simuladas rotações de 2º, 5º e 8º da mandíbula nos dois eixos, tanto para abertura como fechamento, e quantificadas as diferenças nos pontos da linha média inferior (LMI) e pogônio (Pg). O teste t pareado foi utilizado para examinar as diferenças entre as médias nas posições desses pontos (p<0,05). Os eixos verdadeiros localizaram-se dentro de um raio de 5 mm do anatômico em 67,86% da amostra. A distância absoluta média entre os eixos foi de 4,79 mm, enquanto que a vetorial foi de 2,33 no plano horizontal e 3,03 mm no vertical, resultando na direção anteroinferior em 71,43% dos eixos verdadeiros. Houve diferença estatisticamente significante na posição dos pontos LMI e Pg para todas as magnitudes e direções, entre os eixos. O eixo verdadeiro está localizado na direção anteroinferior em relação ao anatômico. Os efeitos na mandíbula são significantes e diferentes em todas as amplitudes, tanto para abertura como fechamento, porém com possível pequena relevância clínica. / The aim of this study was to compare the true hinge axis to the anatomic one in a virtual 3D environment, and also their respective effects on two mandibular anatomic points. The true axis has been determined in 14 individuals by means of axiography, and later transferred to a virtual environment by CBTC, where the anatomical axis was determined, and measured the distances between them. Mandibular rotation of 2º, 5º and 8º in both axes were performed, both for opening and closing, as well as the quantification of the difference found in the points of the lower midline (LM) and pogonion (Pg). Paired t-test was used to examine differences between the average values in the position of those points (p<0,05). The true axis was located within a 5mm-radius of the anatomic axis throughout 67.86% of the sample. The average absolute distance between the axes was 4.79 mm, while the vector distance was 2.33 mm in the horizontal plane e 3.03mm in the vertical plane, amounting to an anteriorinferior direction of 71.43% of the true axis. There was significant difference in the position of points LM and Pg to all magnitudes and directions within the axes. The true hinge axis is located in the anterior-inferior direction in relation to the anatomic axis. The effects observed onto the mandible are significant and different in all amplitudes, both for opening and closing positions, however they present small clinical relevance.
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Volumetric HiLo microscopy employing an electrically tunable lensPhilipp, Katrin, Smolarski, André, Koukourakis, Nektarios, Fischer, Andreas, Stürmer, Moritz, Wallrabe, Ulrike, Czarske, Jürgen W. 11 October 2017 (has links) (PDF)
Electrically tunable lenses exhibit strong potential for fast motion-free axial scanning in a variety of microscopes. However, they also lead to a degradation of the achievable resolution because of aberrations and misalignment between illumination and detection optics that are induced by the scan itself. Additionally, the typically nonlinear relation between actuation voltage and axial displacement leads to over- or under-sampled frame acquisition in most microscopic techniques because of their static depth-of-field. To overcome these limitations, we present an Adaptive-Lens-High-and-Low-frequency (AL-HiLo) microscope that enables volumetric measurements employing an electrically tunable lens. By using speckle-patterned illumination, we ensure stability against aberrations of the electrically tunable lens. Its depth-of-field can be adjusted a-posteriori and hence enables to create flexible scans, which compensates for irregular axial measurement positions. The adaptive HiLo microscope provides an axial scanning range of 1 mm with an axial resolution of about 4 μm and sub-micron lateral resolution over the full scanning range. Proof of concept measurements at home-built specimens as well as zebrafish embryos with reporter gene-driven fluorescence in the thyroid gland are shown.
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3D scanning of transparent objects / Numérisation 3D d'objets transparentsEren, Gönen 22 October 2010 (has links)
Beaucoup de tâches pratiques dans l'industrie, tels que l'inspection automatique ou la vision robotique, nécessitent souvent de numérisation de formes en trois dimensions (3D) avec des techniques non-contact. Toutefois, les objets transparents, tels que ceux en verre, posent encore des difficultés pour les techniques classiques de numérisation. La reconstruction de la géométrie de surface pour les objets transparents est compliquée par le fait que la lumière est transmise à travers, réfracté et dans certains cas, réfléchie par la surface. Les approches actuelles ne peut traiter que les sous-classes d'objets. Les algorithmes sont encore très spécifiques et ne sont généralement pas applicables. En outre, de nombreuses techniques exigent un effort considérable d'acquisition et de calibration. Cette thèse propose une nouvelle méthode de détermination de la forme de la surface des objets transparents. La méthode est basée sur le chauffage locale de la surface et sur l'imagerie thermique. Tout d'abord, la surface de l'objet est chauffé avec une source laser. Une image thermique est acquis, et les coordonnées en pixels du point d'échauffement sont calculés. Ensuite, les coordonnées 3D de la surface sont déterminées en utilisant triangulation et l'étalonnage initial du système. Le processus est répété en déplaçant l'objet transparent pour reprendre sa forme de surface complète. Cette méthode est appelée "Scanning From Heating". Considérant le faisceau laser comme une source de chauffage point et la surface de l'objet localement plane à la zone d'impact, la méthode est utilisée pour obtenir les normales de la surface de l'objet, en plus des coordonnées 3D. Un prototype base sur cette méthode a été développé pendant la thèse. / Many practical tasks in industry, such as automatic inspection or robot vision, often require scanning of three-dimensional shapes with non-contact techniques. However, transparent objects, such as those made of glass, still pose difficulties for classical scanning techniques. The reconstruction of surface geometry for transparent objects is complicated by the fact that light is transmitted through, refracted and in some cases reflected by the surface. Current approaches can only deal relatively well with sub-classes of objects. The algorithms are still very specific and not generally applicable. Furthermore, many techniques require considerable acquisition effort and careful calibration. This thesis proposes a new method of determining the surface shape of transparent objects. The method is based on local surface heating and thermal imaging. First, the surface of the object is heated with a laser source. A thermal image is acquired, and pixel coordinates of the heated point are calculated. Then, the 3D coordinates of the surface are computed using triangulation and the initial calibration of the system. The process is repeated by moving the transparent object to recover its surface shape. This method is called Scanning From Heating. Considering the laser beam as a point heating source and the surface of the object locally flat at the impact zone, the Scanning From Heating method is extended to obtain the surface normals of the object, in addition to the 3D world coordinates. A scanner prototype based on Scanning From Heating method has been developed during the thesis.
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Ferramentas interativas de auxílio a diagnóstico por neuro-imagens 3D / Interactive tools for volumetric neuroimage based diagnosisYauri Vidalón, José Elías 22 August 2018 (has links)
Orientador: Wu Shin-Ting / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-22T07:56:06Z (GMT). No. of bitstreams: 1
YauriVidalon_JoseElias_M.pdf: 9888204 bytes, checksum: 2eb49026222826c846f3aeb94929c1c6 (MD5)
Previous issue date: 2012 / Resumo: Por apresentar alta resolução espacial e espectral, é crescente o uso de imagens de ressonância magnética tanto no estudo dos órgãos humanos como também no diagnóstico das anormalidades estruturais e funcionais e no planejamento e treinamento cirúrgico. Junto com a rápida evolução dos algoritmos de processamento de imagens médicas, surgiram na última década aplicativos de diagnósticos assistidos por computador especializados em mamografia, angiografia e imagens da região torácica. A complexidade estrutural do cérebro e as diferenças anatômicas individuais do crânio constituem, no entanto, ainda desafios ao desenvolvimento de um sistema de diagnóstico especializado em neuro-imagens. A intervenção de especialistas é muitas vezes imprescindível na identificação e na interpretação dos achados radiológicos. Nesta dissertação, propomos o uso de três técnicas para auxiliar os especialistas da área médica na busca por achados radiológicos sutis de forma interativa. São apresentados dois objetos de interação, lente móvel e sonda volumétrica, que permitem atualizar continuamente os dados em foco enquanto são manipulados. Com isso, é possível investigar regiões cerebrais de interesse preservando o seu contexto. E, a fim de facilitar a percepção visual das variações funcionais ou estruturais sutis, propomos utilizar um editor de funções de transferência 1D para realçar ou aumentar o contraste entre os voxels adjacentes. As ferramentas foram avaliadas por um grupo de especialistas em neuro-imagens do Laboratório de Neuro-imagens da Faculdade de Ciências Médicas da Unicamp / Abstract: Because of its high spatial and spectral resolution, it is increasing the use of magnetic resonance images both in the study of human organs as well as in the diagnosis of structural and functional abnormalities and in the surgery planning and training. Along with the rapid evolution of medical image processing algorithms, computer-aided diagnostics systems specialized in mammography, angiography, and computed tomography and magnetic resonance of the thorax have emerged in the last decade. The structural complexity of the brain and individual anatomical shape of skulls are, however, challenges in developing a diagnostic system specializing in neuro-imaging. Expert interventions are still essential both in the identification and in the interpretation of radiological findings. In this dissertation, we propose the use of three techniques to aid the medical experts in the search of subtle findings in an interactive way. We present two widgets, movable lens and volumetric probe, that allow one to update continuously the volume data in focus while are manipulated. In this way, it is possible to investigate brain regions of interest preserving its context. And, in order to facilitate the visual perception of the subtle functional or structural changes, we propose to use an editor of 1D transfer function to enhance or to increase the contrast between adjacent voxels. The tools were assessed by the neuro-imaging experts of the Laboratory of Neuro-Images of the Faculty of Medical Sciences of Unicamp / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica
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Primena jednodimenzionalnog i volumetrijskog merenja u evaluaciji terapijskog odgovora karcinoma pluća višeslojnom kompjuterizovanom tomografijom / The unidimensional and volumetric measurement evaluation of therapy responce in lung carcinomaby multislice computed tomographyVasić Nada 21 October 2019 (has links)
<p>Karcinom pluća predstavlja vodeći uzrok smrtnosti među svim malignim obolenjima, a uprkos dostignućima u dijagnostici i terapiji u poslednjih 30 godina nije došlo do bitnog poboljšanja izuzetno niske ukupne stope petogodišnjeg preživljavanja kod ovih pacijenata. U momentu otkrivanja bolesti preko trećine svih novootkrivenih slučajeva nalazi se u IV stadijumu bolesti. Precizno i adekvatno praćenje odgovora tumora na terapijski tretman kod obolelih od karcinoma pluća u IV stadijumu kao i što ranije utvrđivanje progresije bolesti, odnosno neefikasnosti terapijskog tretmana kod ove grupe bolesnika od velikog je značaja, jer za ove pacijente hemioterapija predstavlja jedinu terapijsku opciju. Postojeće konvencionalne metode jednodimenzionalnih merenja i procena tumorskog odgovora na terapijski tretman prema RECIST kriterijumima ne koriste sve prednosti CT dijagnostike i oslanjaju se na subjektivnost manuelnih merenja. Primena naprednih radioloških tehnika, poput volumetrije, mogu doprineti razvoju imidžing praćenja terapijskog odgovora tumora kod pacijenata sa karcinomom pluća. Cilj istraživanja je evaluacija primene jednodimenzionalnog i volumetrijskog merenja u proceni terapijskog odgovora karcinoma pluća višeslojnom kompjuterizovanom tomografijom. Metodologija: Istraživanjem po tipu prospektivne studije obuhvaćeno je 100 pacijenata obolelih od karcinoma pluća u IV stadijumu bolesti u vreme otkrivanja, koji su ispitivani u periodu od 2013. do 2016. godine u Institutu za plućne bolesti Vojvodine u Sremskoj Kamenici i koji su ispunili kriterijume za ulazak u studiju. Kod svih pacijenata obuhvaćenih istraživanjem, dva radiologa nezavisno su evaluirali sve CT preglede grudnog koša, izvršili jednodimenzionalna manuelna i volumetrijska merenja odabranih target lezija što je omogućilo utvrđivanje unutarčitačke i međučitačke varijabilnosti i slaganja rezultata merenja target lezija primenom ispitivanih metoda. Na osnovu rezutata izvršenih merenja urađena je kategorizacija terapijskog odgovora tumora primenom konvencionalnih RECIST kriterijuma kao i primenom modifikovanog sistema kategorizacije za volumetrijsku evaluaciju terapijskog odgovora sa modifikovanim optimalnim graničnim vrednostima za klasifikovanje progresije bolesti i pozitivnog odgovora na terapiju, izračunatim na osnovu ispitivanog uzorka (model 3Dindividual). Urađeno je poređenje manuelne i volumetrijske procene terapijskog odgovora primenom razičitih ispitivanih sistema klasifikacije uz utvrđivanje stepena različite klasifikacije i analizu preživljavanja pacijenata do pojave progresije bolesti. Uticaj morfoloških karakteristika “target” lezija na rezultate volumetrijskog merenja određen je analizom odstupanja izmerenog volumena tumora u odnosu na aritmetičku sredinu između grupa lezija ispitivanih morfooških karakteristika. Rezultati: Primena volumetrijskog merenja, na ispitivanom uzorku, dovodi do niže stope varijabilnosti rezultata merenja dimenzija target lezija u odnosu na konvencionalnu manuelnu metodu merenja i u slučaju međučitačke varijabilnosti (0,9% vs 6,5%) i u pogledu unutarčitačke varijabilnosti (4,9% vs 0,9%). Volumetrijskom evaluacijom terapijskog odgovora tumora uz primenu modifikovanih graničnih vrednosti kategorizacije (model 3D-individual) postiže se značajno različita klasifikacija terapijskog odgovora u odnosu na primenu konvencionalnih RECIST kriterijuma. U slučaju volumetrijske evaluacije terapijskog odgovora, klasifikovanje pacijenata primenom novog sistema kategorizacije ”3D-individual” dovodi do različite klasifikacije u 22,2 % slučajeva u poređenju sa RECIST ekvivalent kriterijumima za volumetriju, uz održavanje jednako dobre predikcije PFS ova dva sistema. Rezultati istraživanja pokazali su da izgled ivica lezija i odnos lezije prema okolnim anatomskim strukturama imaju srednji uticaj na varijabilnost rezultata volumetrijskih merenja. Zaključak: Primena volumetrijskog merenja kao novog aspekta morfološke procene odgovora karcinoma pluća na primenjenu terapiju može unaprediti donošenje terapijskih odluka kako u lečenju individualnih bolesnika tako i u vođenju kliničkih istraživanja.</p> / <p>Lung cancer is the leading cause of mortality among all malignancies, and despite advances in diagnostics and therapy over the past 30 years, there has been no significant improvement in the extremely low overall rate of a five-year survival with these patients. At the time of the diagnosis, more than a third of all newly discovered cases are at the IV stage of the disease. Precise and adequate monitoring of the response of the tumor to therapeutic treatment with lung cancer patients in IV stage, as well as the early detection of progression of the disease or inefficiency of therapy in this group of patients is of great importance as chemotherapy is the only therapeutic option for these patients. The existing conventional methods of one-dimensional measurement and assessment of tumor response to therapeutic treatment according to RECIST criteria do not use all the advantages of CT diagnostics and rely on the subjectivity of manual measurements. Advanced radiological techniques, such as volumetry, can contribute to the development of the image monitoring of the therapeutic response of tumors in patients with lung cancer. The aim of this study is to evaluate the application of one-dimensional and volumetric measurement in the assessment of the therapeutic response to lung cancer with multslice computerized tomography. Methodology: A study per type of prospective study included 100 patients with lung cancer at the IV stage of the disease at the time of detection, which were tested in the period between 2013 and 2016 at the Institute of Pulmonary Diseases of Vojvodina in Sremska Kamenica and met the criteria for entering the study. With all patients involved in the study, two radiologists independently assessed all CT chest exams, performed one-dimensional manual and volumetric measurements of selected target lesions, which enabled the determination of intraobserver and interobserver variability and the agreement of the target lesion measurement results using the test method. Based on the results of the performed measurements, the categorization of the therapeutic response of the tumor with conventional RECIST criteria, as well as the application of a modified categorization system for volumetric assessment of the therapeutic response with modified optimal limit values for classification (progression of the disease and positive response to the therapy) was performed, calculated on the basis of the tested sample. Comparison of manual and volumetric estimates of the therapeutic response was made using various classification systems with the determination of the degree of difference in classification and analysis of survival of patients until the progression of the disease. The influence of morphological characteristics of target lesions on the results of volumetric measurement was determined by the analysis of the deviation of the measured tumor volume relative to the arithmetic mean between the groups of lesions of the examined morphological characteristics. Results: The application of volumetric measurements on the test sample leads to a lower rate of variability in the results of measuring the dimensions of the target lesions compared to the conventional manual measurement method, and in the case of interobserver variability (0.9% versus 6.5%) and in terms of intraobserver variability (4.9% to 0.9%). The volumetric assessment of the therapeutic response of the tumor using modified boundary categorization values (3Dindividual model) results in a significantly different classification of the therapeutic response in relation to the use of conventional RECIST criteria. In the case of volumetric assessment of the therapeutic response, the classification of patients using the new “3D-individual” categorization system leads to a misclassification in 22.2% of cases compared to RECIST equivalent to volumetric criteria, reflecting the equally good predictability of PFS in these two systems. The results of the study showed that the appearance of the lesion margins and relation to the surrounding anatomical structures influenced the variability of the results of volumetric measurements. Conclusion: The application of volumetric measurements as a new aspect of the morphological evaluation of lung cancer response to applied therapies can help in making therapeutic decisions both in the treatment of individual patients and in the conduct of clinical trials.</p>
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Volumetric HiLo microscopy employing an electrically tunable lensPhilipp, Katrin, Smolarski, André, Koukourakis, Nektarios, Fischer, Andreas, Stürmer, Moritz, Wallrabe, Ulrike, Czarske, Jürgen W. 11 October 2017 (has links)
Electrically tunable lenses exhibit strong potential for fast motion-free axial scanning in a variety of microscopes. However, they also lead to a degradation of the achievable resolution because of aberrations and misalignment between illumination and detection optics that are induced by the scan itself. Additionally, the typically nonlinear relation between actuation voltage and axial displacement leads to over- or under-sampled frame acquisition in most microscopic techniques because of their static depth-of-field. To overcome these limitations, we present an Adaptive-Lens-High-and-Low-frequency (AL-HiLo) microscope that enables volumetric measurements employing an electrically tunable lens. By using speckle-patterned illumination, we ensure stability against aberrations of the electrically tunable lens. Its depth-of-field can be adjusted a-posteriori and hence enables to create flexible scans, which compensates for irregular axial measurement positions. The adaptive HiLo microscope provides an axial scanning range of 1 mm with an axial resolution of about 4 μm and sub-micron lateral resolution over the full scanning range. Proof of concept measurements at home-built specimens as well as zebrafish embryos with reporter gene-driven fluorescence in the thyroid gland are shown.
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Sensitivität und Spezifität von Arthroskopie und dreidimensional rekonstruierten CT-Modellen zur Bestimmung der radioulnaren Inkongruenz am kaninen Ellbogengelenk: eine In-vitro-StudieWerner, Hinnerk 07 June 2011 (has links)
Zielstellung: Bei der Frage, ob die Durchführung von Korrekturosteotomien zur Ent-lastung betroffener Areale bei Hunden mit ED sinnvoll ist, erscheint es uns von
zentraler Bedeutung, auch eine geringgradig ausgeprägte RUI präzise zu bestim-men. In der vorliegenden Arbeit wurden deshalb folgende Ziele verfolgt: (1) Evaluie-rung der Sensitivität und Spezifität der Bestimmung von radioulnaren Gelenks-formationen anhand von dreidimensionalen CT-Modellen und der Arthroskopie. (2) Erweiterung des Untersuchungsgutes, da im Gegensatz zu vorangegangenen Stu-dien sowohl Inkongruenzen mit verkürztem Radius (positive RUI) als auch mit ver-kürzter Ulna (negative RUI) einbezogen wurden.
Material und Methode: In das Untersuchungsgut gingen Vordergliedmaßen gesun-der Hunde mittelgroßer und großer Rassen ein. Mit Hilfe eines etablierten Modells wurde experimentell der Radius stufenweise um 1 und 2 mm verkürzt, bzw. verlän-gert. In der ersten Studie wurden 64 radioulnare Gelenksformationen anhand von dreidimensional rekonstruierter CT-Modelle untersucht. In der zweiten Studie wurden 72 radioulnare Gelenksformationen arthroskopisch beurteilt. Die Art der Stufe und ih-re Reihenfolge waren jeweils randomisiert und geblindet. Die Gelenksformationen wurden als -2, -1, 0, 1 und 2 mm Stufe klassifiziert.
Ergebnisse: Für die Bestimmung der radioulnaren Gelenksformation anhand von dreidimensional rekonstruierter CT-Modelle konnte ein Interklassen-Korrelations-koeffizient von 0,87 und ein Intraklassen-Korrelationskoeffizient von 0,96 ermittelt werden. Die mediane Sensitivität im Hinblick auf das Erkennen eines inkongruenten Gelenkes lag bei 0,86 (0,82 - 0,98). Die mediane Spezifität bei 0,77 (0,62 - 0,92). Bei der Arthroskopie konnte ein kongruentes Gelenk mit einer Sensitivität von 0,98 (95% KI: 0,90 - 0,99) bestimmt werden. Die Spezifität ein kongruentes Gelenke richtig zu diagnostizieren, lag bei 0,89 (95% KI: 0,65 – 0,98).
Schlussfolgerungen: Die Abweichungen zwischen den drei Untersuchern in der ersten Studie legen nahe, dass die Genauigkeit der Bestimmung von radioulnaren Inkongruenzen durch entsprechendes Training deutlich verbessert werden können. Die besten Ergebnisse konnte der Untersucher erzielen, der sich am längsten mit der beschriebenen Technik befasst hatte. Wir postulieren daher, dass die Genauigkeit der semiquantitativen Beurteilung der RUI anhand dreidimensional rekonstruierter CT-Modelle bei regelmäßiger Schulung zunimmt. Dieses Diagnostikum ist in-vitro präzise, wiederholbar und ermöglicht eine nicht invasive Beurteilung der subchondra-len Gelenkflächen.
Die Arthroskopie erlaubt eine direkte Visualisierung und Palpation der intraartiku-lären Strukturen und eine präzise Bestimmung sowohl einer positiven als auch
negativen RUI. Festzuhalten bleibt, dass es eine minimal invasive Technik ist und sich somit als Standard- beziehungsweise Vorsorgeuntersuchung zur Diagnostik der ED beim Hund kaum eignet. Im Vergleich zu Röntgen- und CT-Untersuchungen kön-nen mittels Arthroskopie jedoch die besten Ergebnisse zur Bestimmung der radio-ulnaren Gelenksformation in-vitro erzielt werden.
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Análises morfológica e dinâmica da coronária baseadas no processamento tridimensional de exames de ultrassonografia intravascular / Morphological and dynamic analysis of the coronary based on tridimensional image processing of intravascular ultrasound examinationMatsumoto, Monica Mitiko Soares 05 November 2010 (has links)
Na prática intervencionista, a ultrassonografia intravascular (USIV) é usada para se obter informações quantitativas e qualitativas do acometimento aterosclerótico, de forma complementar à angiografia. Esta tese teve como objetivos explorar a característica tomográfica do exame de USIV, bem como sua dinâmica dentro do ciclo cardíaco. Para isso, desenvolvemos técnicas de processamento de imagens médicas. Primeiramente, investigamos a reconstrução tridimensional da coronária baseando-nos apenas nas imagens de USIV, ou seja, sem a angiografia, como é feita a reconstrução atualmente. Na análise da dinâmica, fizemos um estudo para dispor volumes da coronária em diferentes fases do ciclo cardíaco de forma que estivessem alinhados espacialmente. Como consequência dos tratamentos propostos anteriormente, realizamos estudos sobre a quantificação de propriedades mecânicas dentro das condições oferecidas no intervalo de um ciclo cardíaco. As metodologias propostas foram aplicadas em simulações numéricas desenvolvidas neste trabalho e em exames reais. Obtivemos resultados compatíveis com os objetivos iniciais para reconstrução tridimensional da USIV em simulações numéricas. Na análise da dinâmica, a reconstrução de volumes em diferentes fases do ciclo e o alinhamento espacial possibilitaram a quantificação da variação setorial de volume da luz do vaso durante o ciclo cardíaco / In percutaneous coronary interventions, intravascular ultrasound (IVUS) examination is used to retrieve quantitative and qualitative information about the atherosclerotic plaque progression, complementary to angiography examination. This thesis has as objectives to explore the tomographic characteristic of the IVUS examination, as well as its dynamics within a cardiac cycle. For that purpose, medical image processing techniques were developed. Firstly, we have investigated how to reconstruct the tridimensional coronary based only on IVUS images, that is, without angiography, as it is done nowadays. Regarding dynamic analysis, we have studied models to build volumes of the coronary in distinct phases of the cardiac cycle in a spatial aligned way. Conversantly, as a consequence of the previous image processing methods, we have studied the quantification of mechanical properties of the vessel wall within a cardiac cycle. The methodologies proposed were applied in numeric phantoms developed in this work and also in real IVUS examinations. As result, tridimensional reconstruction was successful in the numeric phantom approach. In dynamics analysis, the reconstruction in distinct cardiac phases and volumes spatial alignment enabled the quantification of lumen volume variation during the cardiac cycle
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