Sökning: "Medical Radiation Physics"

Visar resultat 1 - 5 av 116 avhandlingar innehållade orden Medical Radiation Physics.

  1. 1. Resource efficient automatic segmentation of medical images

    Författare :Minh Hoang Vu; Tommy Löfstedt; Tufve Nyholm; Anders Garpebring; Joakim Jonsson; Örjan Smedby; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; MEDICIN OCH HÄLSOVETENSKAP; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; MEDICAL AND HEALTH SCIENCES; radiotherapy; medical imaging; deep learning; convolutional neural network; generative adversarial network; data augmentation; semantic segmentation; classification; activation map compression; radiofysik; radiation physics;

    Sammanfattning : Cancer is one of the leading causes of death worldwide. In 2020, there were around 10 million cancer deaths and nearly 20 million new cancer cases in the world. Radiation therapy is essential in cancer treatments because half of the cancer patients receive radiation therapy at some point. LÄS MER

  3. 2. Quality assurance for magnetic resonance imaging (MRI) in radiotherapy

    Författare :Mary Adjeiwaah; Tufve Nyholm; Rob HN Tijssen; Umeå universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; MEDICIN OCH HÄLSOVETENSKAP; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; MEDICAL AND HEALTH SCIENCES; Magnetic resonance imaging; Radiotherapy; geometric distortions; patient-induced susceptibilities MR-only; radiofysik; radiation physics;

    Sammanfattning : Magnetic resonance imaging (MRI) utilizes the magnetic properties of tissues to generate image-forming signals. MRI has exquisite soft-tissue contrast and since tumors are mainly soft-tissues, it offers improved delineation of the target volume and nearby organs at risk. LÄS MER

  4. 3. Spectral Mammography with X-Ray Optics and a Photon-Counting Detector

    Författare :Erik Fredenberg; Mats Danielsson; Björn Cederström; Jeffrey H. Siewerdsen; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURVETENSKAP; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; MEDICIN OCH HÄLSOVETENSKAP; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; MEDICAL AND HEALTH SCIENCES; mammography; x-ray optics; photon counting; spectral shaping; spectral imaging; collimation; radiation dose; signal-to-noise ratio; quantum noise; anatomical noise; spatial resolution; x-ray flux; ; TECHNOLOGY; TEKNIKVETENSKAP; Engineering physics; Teknisk fysik; Optical physics; Optisk fysik; Other engineering physics; Övrig teknisk fysik; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik; Medical engineering; Medicinsk teknik; Radiological research; Radiologisk forskning;

    Sammanfattning : Early detection is vital to successfully treating breast cancer, and mammography screening is the most efficient and wide-spread method to reach this goal. Imaging low-contrast targets, while minimizing the radiation exposure to a large population is, however, a major challenge. LÄS MER

  5. 4. The microdosimetric variance-covariance method used for beam quality characterization in radiation protection and radiation therapy

    Författare :Jan Erik Lillhök; Lennart Lindborg; Bernd Grosswendt; Stockholms universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; ionizing radiation; radiation quality; radiation protection; radiation therapy; microdosimetry; nanodosimetry; variance-covariance method; Radiological physics; Radiofysik; medicinsk strålningsfysik; Medical Radiation Physics;

    Sammanfattning : Radiation quality is described by the RBE (relative biological effectiveness) that varies with the ionizing ability of the radiation. Microdosimetric quantities describe distributions of energy imparted to small volumes and can be related to RBE. LÄS MER

  7. 5. Quantitative methods for tumor imaging with dynamic PET

    Författare :Ida Häggström; Anne Larsson; Mikael Karlsson; Lennart Johansson; Jens Sörensen; Magnus Dahlbom; Umeå universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; Dynamic positron emission tomography; PET; tumor imaging; compartment modeling; Monte Carlo; radiofysik; radiation physics;

    Sammanfattning : There is always a need and drive to improve modern cancer care. Dynamic positron emission tomography (PET) offers the advantage of in vivo functional imaging, combined with the ability to follow the physiological processes over time. LÄS MER