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Visar resultat 1 - 5 av 10 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Spectral Computed Tomography with a Photon-Counting Silicon-Strip Detector

   Författare :Mats Persson; Mats Danielsson; Hans Bornefalk; Jiang Hsieh; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Photon-counting; silicon-strip detector; spectral computed tomography; ring artifacts; fluence rate; basis material decomposition; sub-pixel information; Fysik; Physics;

   Sammanfattning : Computed tomography (CT) is a widely used medical imaging modality. By rotating an x-ray tube and an x-ray detector around the patient, a CT scanner is able to measure the x-ray transmission from all directions and form an image of the patient’s interior. LÄS MER

3. 2. A Segmented Silicon Strip Detector for Photon-Counting Spectral Computed Tomography

   Författare :Cheng Xu; Hans Bornefalk; Mats Danielsson; Ami Altman; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; photon counting; spectral computed tomography; silicon strip detector; ASIC; energy resolution; cadmium telluride; charge sharing; Monte Carlo simulation; synchrotron;

   Sammanfattning : Spectral computed tomography with energy-resolving detectors has a potential to improve the detectability of images and correspondingly reduce the radiation dose to patients by extracting and properly using the energy information in the broad x-ray spectrum. A silicon photon-counting detector has been developed for spectral CT and it has successfully solved the problem of high photon flux in clinical CT applications by adopting the segmented detector structure and operating the detector in edge-on geometry. LÄS MER

4. 3. Quantification and Maximization of Performance Measures for Photon Counting Spectral Computed Tomography

   Författare :Moa Yveborg; Hans Bornefalk; Franz Pfeiffer; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spectral computed tomography; silicon detector; detectability index; photon counting; Hotelling SDNR; material basis decomposition;

   Sammanfattning : During my time as a PhD student at the Physics of Medical Imaging group at KTH, I have taken part in the work of developing a photon counting spectrally resolved silicon detector for clinical computed tomography. This work has largely motivated the direction of my research, and is the main reason for my focus on certain issues. LÄS MER

5. 4. Spectral Photon-Counting Computed Tomography with Silicon Detectors: New Models and Applications

   Författare :Fredrik Grönberg; Mats Danielsson; Mats Persson; Amir Pourmorteza; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; photon-counting; spectral computed tomography; material decomposition; pulse pileup; Compton scatter; image formation; fotonräknande; spektral datortomografi; materialbasupdelning; pulsöverlagring; Comptonspridning; bildbildning; Physics; Fysik;

   Sammanfattning : X-ray computed tomography (CT) is a widely used imaging modality that enables visualization of nearly every part of the human body. It is used for diagnosis of disease and injury as well as medical treatment planning. LÄS MER

7. 5. An Event-Reconstructing Silicon Detector for 1 µm Resolution Spectral Computed Tomography

   Författare :Christel Sundberg; Mats Danielsson; Julia Herzen; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; photon-counting; silicon detector; spectral computed tomography; subpixel resolution; dose efficiency; coincidence tracking; event reconstruction; fotonräknande; kiseldetektor; spektral datortomografi; subpixelupplösning; doseffektivitet; koincidensspårning; händelserekonstruktion; Fysik; Physics;

   Sammanfattning : Computed tomography (CT) is a medical imaging modality in which cross-sectional images of the human body are created using x-rays. Commercial CT scanners utilize energy-integrating detectors to measure the x-ray attenuation. However, photon-counting detectors with energy-discriminating abilities have started to emerge. LÄS MER