Ce travail de thèse concerne le traitement d’image fDOT (fDOT pour fluorescence diffuse optical tomography) suit vers deux axes. Le recalage d'images fDOT à l’aide de l’imagerie TEP (tomographie par émission de positons) et l’amélioration des reconstructions fDOT à l’aide de miroirs pour collecter des projections complémentaires. Il est présenté en deux parties : Dans la première partie, une méthode automatique pour recaler les images de fDOT avec les images de Tomographie par Emission de Positons (TEP) développée dans le but de corréler l’ensemble des informations issues de chaque modalité. Cette méthode de recalage est basée sur une détection automatique de marqueurs fiduciaires présents dans les deux modalités. La particularité de cette méthode est l’utilisation de l’image de surface obtenue en fDOT, qui sert à identifier la position en Z des marqueurs fiduciaires dans les images optiques. Nous avons testé cette méthode sur un modèle de souris porteuses de xénogreffes de tumeurs de cellules cancéreuses MEN2A qui imitent un carcinome thyroïdien médullaire humain, après une double injection de traceur radioactif : [18F]2-fluoro-2-Deoxy-D-glucose (FDG) pour l’imagerie TEP et un traceur optique d’infrarouge fluorescent, le Sentidye. Grâce à la précision de notre méthode, nous arrivons à démontrer que le signal Sentidye est présent à la fois dans la tumeur et les vaisseaux environnants [1]. La qualité des images fDOT est dégradée selon l’axe Z du fait d’un nombre limité de projections pour la reconstruction. Dans la deuxième partie, le travail s’est orienté vers une nouvelle méthode de reconstruction d’images fDOT à partir d’un nouveau système d’acquisition multi-angulaire avec deux miroirs placés de chaque côté de l’animal. Ce travail a été mené en collaboration avec le département CS d’University College London (UCL), partenaire du projet Européen FMT-XCT. Le logiciel TOAST développé par cette équipe a été utilisé comme source pour l’algorithme de reconstruction, et modifié pour s’adapter à notre problématique. Après plusieurs essais concernant l’ajustement des paramètres du programme, nous avons appliqué cette méthode sur un fantôme réaliste des tissus biologiques et chez la souris. Les résultats montrent une amélioration de l’image reconstruite d’un fantôme semi-cylindrique et de l’image de rein chez la souris, pour lesquelles la méthode des miroirs est supérieure à la méthode classique sans miroir. Malgré tout, nous avons observé que les résultats étaient très sensibles à certains paramètres, d’où une performance de reconstruction variable d’un cas à l’autre. Les perspectives futures concernent l’optimisation des paramètres afin de généraliser l’approche multi-angle. / This thesis concerns the image processing of fluorescence diffuse optical tomography (fDOT), following two axes: FDOT image co-registration with PET (positron emission tomography) image and improvement of fDOT image reconstructions using mirrors to collect additional projections. It is presented in two parts:In the first part, an automatic method to co-register the fDOT images with PET images has been developed to correlate all the information from each modality. This co-registration method is based on automatic detection of fiducial markers (FM) present in both modalities. The particularity of this method is the use of optical surface image obtained in fDOT imaging system, which serves to identify the Z position of FM in optical images. We tested this method on a model of mice bearing tumor xenografts of MEN2A cancer cells that mimic a human medullary thyroid carcinoma, after a double injection of radiotracer [18F] 2-fluoro-2-Deoxy-D-glucose ( FDG) for PET imaging and optical fluorescent infrared tracer Sentidye. With the accuracy of our method, we can demonstrate that the signal of Sentidye is present both in the tumor and surrounding vessels.The fDOT reconstruction image quality is degraded along the Z axis due to a limited number of projections for reconstruction. In the second part, the work is oriented towards a new method of fDOT image reconstruction with a new multi-angle data acquisition system in placing two mirrors on each side of the animal. This work was conducted in collaboration with the CS Department of University College London (UCL), a partner of the European project FMT-XCT. TOAST software developed by this team was used as source code for the reconstruction algorithm, and was modified to adapt to the concerned problem. After several tests on the adjustment of program parameters, we applied this method on a phantom that simulating the biological tissue and on mice. The results showed an improvement in the reconstructed image of a semi-cylindrical phantom and the image of mouse kidney, for which the reconstruction of the mirrors geometry is better than that of conventional geometry without mirror. Nevertheless, we observed that the results were very sensitive to certain parameters, where the performance of reconstruction varies from one case to another. Future prospectives concern the optimization of parameters in order to generalize the multi-angle approach.

This thesis deals with developing of image processing algorithm for robots controlled by informations taken from visual system. Core of the used system constitutes low-budget platform Raspberry Pi. Before the development of algorithm there is a series of test for image processing which discovers possibilities of used platform. Problem solution is divided to several parts. Limited performance frequently leads to individual problem solving. Afterall is shown sensitivity and performance analysis of developed solution.

Radiotherapy is a common and useful method for treating prostate cancer, often using gold fiducial markers in the prostate as guidance. However, when there is a high risk of lymph node involvement, the independent motion of volumes causes complications in patient positioning since there is a choice between position against the gold fiducial markers or the bone anatomy. This leads to expansion of margins for either the prostate or the pelvic lymph nodes. In this thesis two different treatment strategies were performed and compared against given treatment plans. The purpose was to evaluate the standard treatment and to be able to recommend a new clinical approach for treatment of high-risk prostate cancer. Nine high-risk prostate cancer patients with their given treatment plans were used as a baseline. The patients underwent a planning CT and five CBCTs during the treatment. Two new treatment plan setups were done, a robust treatment and a sequential treatment with three and nine different plans respectively. The baseline and the robust treatment used gold fiducial markers as reference, with a prescribed dose of 2.20 Gy over 35 fractions with a VMAT. The sequential treatment used both gold fiducial markers and bone anatomy as reference, done by 35 fractions with a prescribed dose of 0.6 Gy with a single arc and 1.6 Gy with a dual arc respectively. A total of thirteen different treatment plan setups for each patient were simulated 100 times each, resulting in 11700 simulated treatments in total. The resulting simulated treatments were evaluated by the percentage passing nine different clinical goals, as well as dose and percentage volume averages for these goals. The results from the simulated robust treatments showed a decrease in percentage passing and D98 for the prostate and an increase in percentage passing and D98 for the lymph nodes and vesicles compared to the baseline. An increase in percentage passing and D98 was seen in the sequential treatment strategy for both targets compared to the baseline. The rectum had a larger percentage passing the clinical goals and a lower V69, V74 and V59 for both the robust and sequential treatment strategies. The D2 for the external were lower in the robust treatment strategy but higher in the sequential treatment strategy, while the D2 to the femoral heads were lower for both compared to the baseline treatment strategy. In conclusion, an improved dose coverage was seen in the sequential strategy with good sparing of risk organs. The robust treatment strategy showed promising results for sparing risk organs, but with a less robust dose coverage of the prostate.